Previous studies show that most parts of China have registered an increased heat resource against the background of global warming, which extends crops' growing season and allows thermophilic crops to move further north, changing the pattern of cropping systems. During the period of 1961-2009, the southern rice growing areas witnessed a noticeably increased active accumulated temperature (≥ 10 °C), with an averaged active accumulated temperature at 5712.8 °C in the 60's, and 5686.3 °C and 5677.0 °C in the 70's and 80's, respectively. The same indicator rose to 5809.8 °C in the 1990's, or 97.0 °C up compared with the 60's. During the period of 2001-2009, the averaged active accumulated temperature hit 5980.8°C, or 268.0 °C higher compared with the 60's, or 303.8 °C up against the 80's. During

114 the Economy, Human Health, and on Urban and Natural Environments

80 90 100 110 120 130

**3.2. Climate change impact on the northward shift of double rice cropping in South**

**3.2.1 Active accumulated temperature variation across the southern rice growing**

Paddy rice is a short-day plant which needs the warm and wet environment. Rice growing activities have to be defined in line with a range of ecological and environmental elements, including heat, growing season, water, sunshine, elevation, soil, production condition, and cropping system (Cheng, 2007). Heat resource makes a pivotal element in defining the distribution of rice growing areas. Theoretically, the heat resource defined for paddy rice is technically expressed in an active accumulated temperature≥10°C. Active accumulated temperature is the sum total of the temperatures that are above the lowest biological temperature a plant has had during the entire growth season in a year, or the sum total of the averaged daily temperatures that are above a given threshold value. In southern China, triple cropping rice can be planted when the active accumulated temperature was more than 7000°C, and double cropping rice can grow when the active accumulated temperature was

Previous studies show that most parts of China have registered an increased heat resource against the background of global warming, which extends crops' growing season and allows thermophilic crops to move further north, changing the pattern of cropping systems. During the period of 1961-2009, the southern rice growing areas witnessed a noticeably increased active accumulated temperature (≥ 10 °C), with an averaged active accumulated temperature at 5712.8 °C in the 60's, and 5686.3 °C and 5677.0 °C in the 70's and 80's, respectively. The same indicator rose to 5809.8 °C in the 1990's, or 97.0 °C up compared with the 60's. During the period of 2001-2009, the averaged active accumulated temperature hit 5980.8°C, or 268.0 °C higher compared with the 60's, or 303.8 °C up against the 80's. During

Fig. 4. Spatial distribution of precipitation variation, 1961-2009 (mm/10a).

20

more than 5300°C (Cheng, 2007).

**China**

**areas**

30

40

50

the 19 years running from 1991 to 2009, 16 years reported an active accumulated temperature that was higher than it from 1971 to2000, with 1998 being the warmest at 6144.9 °C, or 420.6 °C higher than what would have been in a normal year. The same indicator appeared at 6011.1 °C in 2009, or 286.8 °C higher compared with a normal year (Fig. 5).

Fig. 5. Active accumulated temperature variation in the southern rice growing areas, 1961- 2009 (°C).

Rice is a staple food crop in China. In 2000, the rice sown area reached 29.962 million hectares, accounting for 27.6% of the grain sown area in the country, with a yield of 187.91 million tons, or 40.7% of the total food crop yield in the country (CSY, 2001). Heat resource defines the distribution and cropping of rice growing. For example, an area having an accumulated temperature at 2000-5300°C (≥ 10 °C) is desirable for the one-cropping system, while the one at 5300-7000°C may enjoy a double cropping practice. An area with an accumulated temperature at 7000°C or above is allowed to grow three cropping.

During the period of the 1960's-1980's, China saw limited variations in heat distribution. The areas having an annual active accumulated temperature (≥ 10 °C) at 7000°C or above sat mostly in the central and southern part of South China, practicing a three cropping system. The areas with an annual active accumulated temperature (≥ 10 °C) between 5300°C and 7000°C have included most parts of Hunan, Jiangxi, the central and southern part of Zhejiang, most parts of Fujian, the southeast part of Hubei, some parts of Sichuan and Chongqing, and the southern part of Yunnan (Figs. 6).

During the period from the 1990s to 2009, the safe threshold for double cropping (5300°C) and triple cropping (7000°C) moved further north. For example, the northern boundary of double cropping moved up for more than 2 degrees, or some 300 km (Figs. 6). As a result, a range of areas, including the east part of Sichuan, most parts of Chongqing, the east part of Guizhou, most parts of Hubei, most parts of Anhui, and the southern part of Jiangsu, became desirable for double cropping.

China National Climate Center predicts that China will see a further warming climate during the period of 2011-2020 (Ding et al., 2007). Most parts of the country will have a sustained rise of active accumulated temperature. The trend may further increase the heat resource for the newly added double cropping areas. As a result, the northern boundary of

The Influence of Climate Change on Rice in China from 1961 to 2009 117

The growing season duration is also an element that defines the distribution of rice growing areas. For example, early rice is sown in the late February in the southern part of China, with late rice being harvested in the early November. The sowing could be later, starting from the mid-March in the south of the Yangtze River, with late rice becoming ripened in the mid-October. In southern China, triple cropping rice can be planted when the growing season length was longer than 270 days, and double cropping rice can grow when the

During the period of 1961-2009, the duration of rice growing season (the days with an averaged temperature passing the threshold of ≥ 10 °C in the beginning of the growing season and ≥ 20 °C at the end of it) in the southern part of the country was noticeably prolonged (Fig. 7). For example, the duration of rice growing season lasted for 214.9 days in the 60's, with 221.9 days and 211.7 days in the 1970's and 1980's, respectively. In the 90's, an averaged rice growing season would last for 220.3 days, a bit longer compared with the 60's and 80's, though slightly shorter against the 70's. During the period of 2000-2009, the rice growing season rose to 231.4 days in the southern rice growing areas, or 16.5 days longer compared with the 60's, or 19.7 days longer against the 80's. Apparently, the duration of rice growing season has become

Year

In China, the safe rice growing season would last for some 270 days under a triple cropping system, or some 200 days for a double cropping system. In other words, the 270-day growing season is desirable for triple cropping, and the 200-day for double cropping. Figs. 8 show that as far as the safe rice growing season is concerned, climate warming has imposed no significant impacts on the scope of the areas desirable for triple cropping. However, climate warming have noticeably pushed the northern boundary of double cropping further north. Such northward shift has become increasingly noticeable since the 21st century. In the period from the 60s to the 90s, the double cropping system was mainly practiced in the south of the Yangtze River Valley. However, the northern boundary of double cropping has gone further to the north of the Yangtze River since the 21st century, including the northeast part of Sichuan, the east part of Guizhou, Chongqing, most parts of Hubei, the central and southern part of Anhui, and the southern part of Jiangsu. Apparently, the northern boundary of double cropping has gone further north, compared with the 90's.

Fig. 7. Changed duration of rice growing season in the southern rice growing areas, 1961-

**3.2.2 Changed duration of the growing season**

growing season length was longer than 200 days (Cheng, 2007).

noticeably longer in the southern part of China since the 21st century.

Growing season (day)

2009 (day).

double cropping may move further north (Fig.6). These areas apparently need to readjust the cropping system in a scientific manner, in line with the local conditions, adapting to the changed climate resource and environment, and enhancing the utilization of climate resources.

(the data during 1961-2009 from observed meteorological stations, and the data during 2011-2020 projected by RegCM3)

Fig. 6. Distribution of active accumulated temperature (≥ 10 °C) in the southern rice growing areas. Note: the red color represents the areas desirable for triple cropping, and the yellow one for double cropping.

#### **3.2.2 Changed duration of the growing season**

Global Warming Impacts – Case Studies on

116 the Economy, Human Health, and on Urban and Natural Environments

double cropping may move further north (Fig.6). These areas apparently need to readjust the cropping system in a scientific manner, in line with the local conditions, adapting to the changed climate resource and environment, and enhancing the utilization of climate

1961-1970 1971-1980

1981-1990 1991-2000

2001-2009 2011-2020

Fig. 6. Distribution of active accumulated temperature (≥ 10 °C) in the southern rice growing areas. Note: the red color represents the areas desirable for triple cropping, and the yellow

(the data during 1961-2009 from observed meteorological stations, and the data during 2011-2020

resources.

projected by RegCM3)

one for double cropping.

The growing season duration is also an element that defines the distribution of rice growing areas. For example, early rice is sown in the late February in the southern part of China, with late rice being harvested in the early November. The sowing could be later, starting from the mid-March in the south of the Yangtze River, with late rice becoming ripened in the mid-October. In southern China, triple cropping rice can be planted when the growing season length was longer than 270 days, and double cropping rice can grow when the growing season length was longer than 200 days (Cheng, 2007).

During the period of 1961-2009, the duration of rice growing season (the days with an averaged temperature passing the threshold of ≥ 10 °C in the beginning of the growing season and ≥ 20 °C at the end of it) in the southern part of the country was noticeably prolonged (Fig. 7). For example, the duration of rice growing season lasted for 214.9 days in the 60's, with 221.9 days and 211.7 days in the 1970's and 1980's, respectively. In the 90's, an averaged rice growing season would last for 220.3 days, a bit longer compared with the 60's and 80's, though slightly shorter against the 70's. During the period of 2000-2009, the rice growing season rose to 231.4 days in the southern rice growing areas, or 16.5 days longer compared with the 60's, or 19.7 days longer against the 80's. Apparently, the duration of rice growing season has become noticeably longer in the southern part of China since the 21st century.

Fig. 7. Changed duration of rice growing season in the southern rice growing areas, 1961- 2009 (day).

In China, the safe rice growing season would last for some 270 days under a triple cropping system, or some 200 days for a double cropping system. In other words, the 270-day growing season is desirable for triple cropping, and the 200-day for double cropping.

Figs. 8 show that as far as the safe rice growing season is concerned, climate warming has imposed no significant impacts on the scope of the areas desirable for triple cropping. However, climate warming have noticeably pushed the northern boundary of double cropping further north. Such northward shift has become increasingly noticeable since the 21st century. In the period from the 60s to the 90s, the double cropping system was mainly practiced in the south of the Yangtze River Valley. However, the northern boundary of double cropping has gone further to the north of the Yangtze River since the 21st century, including the northeast part of Sichuan, the east part of Guizhou, Chongqing, most parts of Hubei, the central and southern part of Anhui, and the southern part of Jiangsu. Apparently, the northern boundary of double cropping has gone further north, compared with the 90's.

The Influence of Climate Change on Rice in China from 1961 to 2009 119

Precipitation is also in a position to affect the distribution of rice growing areas. In China, both double and triple cropping need an annual rainfall no less than 1,000 mm. Fig. 19 shows that climate warming has produced limited impacts on the rainfall in the southern part of China. In the 60's, the southern part of the country where paddy rice was grown registered an averaged annual precipitation of 1379mm. The 1970's, 1980's, and 1990's recorded a sustained increase of precipitation at 1412 mm, 1435mm, and 1491 mm respectively (Fig. 9) . China, however, has seen a slightly decreased precipitation to 1431

Year

Fig. 9. Annual precipitation variation in the southern rice growing areas, 1961-2009 (mm). In addition, most parts of Hainan Province, the east part of Guangxi, Guangdong, Fujian, and Jiangxi reported an annual precipitation of 1,500 mm or above in the 60's, with the rest of rice growing areas in the south sitting between 1,000mm and 1,500 mm (Fig. 10). In the 70's, the areas enjoying an annual precipitation of 1,500 mm or above did not see much change in number, though the areas sitting between 1,000mm and 1,500 mm in both Sichuan and Jiangsu reported a slight drop in number. In the 80's, the areas having an annual precipitation of 1,500 mm or above in Guangxi saw a slight drop in number, with little change of the areas sitting between ,1000mm and 1,500 mm. In the 90's, the areas having an annual precipitation of 1,500 mm or above in Guangxi reported some increase in number, though the areas sitting between 1,000mm and 1,500 mm in Sichuan suffered a noticeable drop in number. Zhejiang, Anhui, and Jiangxi have reported a noticeably declined number of the areas having an annual precipitation of 1,500 mm or above since the 21st century, with a slight drop of the areas sitting between 1,000mm and 1,500 mm in both Sichuan and

Overall speaking, the southern paddy rice growing areas in China didn't see much change in precipitation during the period of 1961-2009, though a number of provinces, including Jiangsu, Hubei, and Sichuan, had reported a declined number of the areas sitting between

1,000mm and 1,500 mm since the 21st century, which deserves further attention.

**3.2.3 Annual precipitation variation**

mm starting from the 21st century.

Precipitation (mm)

Yunnan.

According to the analysis and prediction made by China National Climate Center, the period of 2011-2020 will see a further intensified climate warming trend in China, with a prolonged rice growing season in the southern part of the country, and a further northward shift of the double cropping boundary. The conclusion agrees with the northward shift of the double cropping boundary depicted by the results of active accumulated temperature calculation.

(the data during 1961-2009 from observed meteorological stations, and the data during 2011-2020 projected by RegCM3)

Fig. 8. Changed duration of rice growing season in the southern rice growing areas (day). Note: the red color represents the areas desirable for triple cropping, and the yellow one for double cropping.

#### **3.2.3 Annual precipitation variation**

Global Warming Impacts – Case Studies on

118 the Economy, Human Health, and on Urban and Natural Environments

According to the analysis and prediction made by China National Climate Center, the period of 2011-2020 will see a further intensified climate warming trend in China, with a prolonged rice growing season in the southern part of the country, and a further northward shift of the double cropping boundary. The conclusion agrees with the northward shift of the double cropping boundary depicted by the results of active accumulated temperature

1961-1970 1971-1980

1981-1990 1991-2000

2001-2009 2011-2020

(the data during 1961-2009 from observed meteorological stations, and the data during 2011-2020

Fig. 8. Changed duration of rice growing season in the southern rice growing areas (day). Note: the red color represents the areas desirable for triple cropping, and the yellow one for

calculation.

projected by RegCM3)

double cropping.

Precipitation is also in a position to affect the distribution of rice growing areas. In China, both double and triple cropping need an annual rainfall no less than 1,000 mm. Fig. 19 shows that climate warming has produced limited impacts on the rainfall in the southern part of China. In the 60's, the southern part of the country where paddy rice was grown registered an averaged annual precipitation of 1379mm. The 1970's, 1980's, and 1990's recorded a sustained increase of precipitation at 1412 mm, 1435mm, and 1491 mm respectively (Fig. 9) . China, however, has seen a slightly decreased precipitation to 1431 mm starting from the 21st century.

Fig. 9. Annual precipitation variation in the southern rice growing areas, 1961-2009 (mm).

In addition, most parts of Hainan Province, the east part of Guangxi, Guangdong, Fujian, and Jiangxi reported an annual precipitation of 1,500 mm or above in the 60's, with the rest of rice growing areas in the south sitting between 1,000mm and 1,500 mm (Fig. 10). In the 70's, the areas enjoying an annual precipitation of 1,500 mm or above did not see much change in number, though the areas sitting between 1,000mm and 1,500 mm in both Sichuan and Jiangsu reported a slight drop in number. In the 80's, the areas having an annual precipitation of 1,500 mm or above in Guangxi saw a slight drop in number, with little change of the areas sitting between ,1000mm and 1,500 mm. In the 90's, the areas having an annual precipitation of 1,500 mm or above in Guangxi reported some increase in number, though the areas sitting between 1,000mm and 1,500 mm in Sichuan suffered a noticeable drop in number. Zhejiang, Anhui, and Jiangxi have reported a noticeably declined number of the areas having an annual precipitation of 1,500 mm or above since the 21st century, with a slight drop of the areas sitting between 1,000mm and 1,500 mm in both Sichuan and Yunnan.

Overall speaking, the southern paddy rice growing areas in China didn't see much change in precipitation during the period of 1961-2009, though a number of provinces, including Jiangsu, Hubei, and Sichuan, had reported a declined number of the areas sitting between 1,000mm and 1,500 mm since the 21st century, which deserves further attention.

The Influence of Climate Change on Rice in China from 1961 to 2009 121

In the most part of the Jiangnan of China, rice would enter the heading, flowering, and filling stages in June and July. In the Jiangnan, the first cropping rice enters the heading and flowering stage in August. This period of time is featured with the positive dominance of subtropical highs, claiming more high temperature days. The abnormal frequency of hot days would result in a shortened period for heading, flowering, and filling, reducing the leaf assimilation on the one hand, and causing the surge of blighted rice and a reduced yield and

In June, hot weather (≥ 35 °C) starts to affect the lower and middle reaches of the Yangtze River. In the early June, this part of the Jiangnan would have 0.3 hot days in a normal year, with 0.5 hot days for the period of 2001-2009. In the mid-June, 0.4 hot days would appear in a normal year, with 0.8 days in the period of 2001-2009. In the late June, 0.6 hot days is a common place, with 1.7 days for the period of 2001-2009. It is noteworthy that the lower and middle reaches of the Jiangnan has witnessed a noticeably raised number of hot days at 2.1

July is a month featured with a noticeably raised number of hot days in the lower and middle reaches of the Yangtze River. In the early July, hot days would reach 1.9 in number in a normal year, with 2.6 days for the years since 2000. The mid-July would produce 2.7 hot days, though 3.5 days since 2000. In the late July, high temperature days would go up to 3.2 days on an average, with 4.5 days for the period of 2000-2009. Technically, the late July claims the most hot days in the lower and middle reaches of the Jiangnan with a noticeably

August starts to see a declined number of hot days in the Jiangnan. In the early August, high temperature days reach 2.9 on an average, though with a slightly descending trend in the past 10 or 20 years. The mid-August would have 1.5 hot days, expecting no ascending trend. In the late August, high temperature days are averaged at 1.2 days. Technically, the early August would have a slightly increased number of high temperature days, and the mid-

Overall, the Jiangnan would have 14.7 hot days for the summer (June-August). The number of high temperature days has witnessed a noticeable rise, especially in the late June and late

The South China starts to have hot days (≥ 35 °C) in June. In the early June, this part of the country would have 0.5 hot days on an average (Table 1), with 0.6 days for the mid-June, and 0.8 days for the late part of the month. This part of the country has registered a

July is featured with a noticeably raised number of hot days, with 1.5 hot days for the early July (Table 1). The mid-July would have 1.9 hot days on an average, though 2-5 days for the years since 2000. The late July has registered a pattern similar to the mid-July, with 2.2 hot days on an average, and a noticeably increased number of hot days to 2-5 days since 2000. In August, the lower and middle reaches of the Yangtze River start to see fewer hot days. The early August is averaged with 1.7 hot days, witnessed a noticeably increased number of hot days in a 10-year period. The mid-August would have 1.4 hot days, and the late August 1.2 hot days. Overall speaking, the early August has slightly more high temperature days,

**3.2.4 High temperature day trends in the southern rice growing areas**

**The Jiangnan region**

July, since 2000. **South China**

quality on the other (Zhang and Wang, 1998).

days during the period of 2005-2009 since 2005 (Table 1).

raised number of hot days in the past 20 years (Table 1).

August a steadily decreased number of hot days since that time on.

noticeably increased number of hot days in the late June since 2000.

China National Climate Center predicts that the southern part of China will not see a large variation in precipitation during the period of 2011-2020 (Ding et al., 2007). As a result, precipitation will produce no significant impacts on the southern rice growing areas in the coming decade if the precipitation change slightly.

(the data during 1961-2009 from observed meteorological stations, and the data during 2011-2020 projected by RegCM3)

Fig. 10. Distribution of annual precipitation in the southern rice growing areas (mm).

#### **3.2.4 High temperature day trends in the southern rice growing areas**

#### **The Jiangnan region**

Global Warming Impacts – Case Studies on

120 the Economy, Human Health, and on Urban and Natural Environments

China National Climate Center predicts that the southern part of China will not see a large variation in precipitation during the period of 2011-2020 (Ding et al., 2007). As a result, precipitation will produce no significant impacts on the southern rice growing areas in the

1961-1970 1971-1980

1981-1990 1991-2000

2001-2009 2011-2020

(the data during 1961-2009 from observed meteorological stations, and the data during 2011-2020

Fig. 10. Distribution of annual precipitation in the southern rice growing areas (mm).

projected by RegCM3)

coming decade if the precipitation change slightly.

In the most part of the Jiangnan of China, rice would enter the heading, flowering, and filling stages in June and July. In the Jiangnan, the first cropping rice enters the heading and flowering stage in August. This period of time is featured with the positive dominance of subtropical highs, claiming more high temperature days. The abnormal frequency of hot days would result in a shortened period for heading, flowering, and filling, reducing the leaf assimilation on the one hand, and causing the surge of blighted rice and a reduced yield and quality on the other (Zhang and Wang, 1998).

In June, hot weather (≥ 35 °C) starts to affect the lower and middle reaches of the Yangtze River. In the early June, this part of the Jiangnan would have 0.3 hot days in a normal year, with 0.5 hot days for the period of 2001-2009. In the mid-June, 0.4 hot days would appear in a normal year, with 0.8 days in the period of 2001-2009. In the late June, 0.6 hot days is a common place, with 1.7 days for the period of 2001-2009. It is noteworthy that the lower and middle reaches of the Jiangnan has witnessed a noticeably raised number of hot days at 2.1 days during the period of 2005-2009 since 2005 (Table 1).

July is a month featured with a noticeably raised number of hot days in the lower and middle reaches of the Yangtze River. In the early July, hot days would reach 1.9 in number in a normal year, with 2.6 days for the years since 2000. The mid-July would produce 2.7 hot days, though 3.5 days since 2000. In the late July, high temperature days would go up to 3.2 days on an average, with 4.5 days for the period of 2000-2009. Technically, the late July claims the most hot days in the lower and middle reaches of the Jiangnan with a noticeably raised number of hot days in the past 20 years (Table 1).

August starts to see a declined number of hot days in the Jiangnan. In the early August, high temperature days reach 2.9 on an average, though with a slightly descending trend in the past 10 or 20 years. The mid-August would have 1.5 hot days, expecting no ascending trend. In the late August, high temperature days are averaged at 1.2 days. Technically, the early August would have a slightly increased number of high temperature days, and the mid-August a steadily decreased number of hot days since that time on.

Overall, the Jiangnan would have 14.7 hot days for the summer (June-August). The number of high temperature days has witnessed a noticeable rise, especially in the late June and late July, since 2000.

#### **South China**

The South China starts to have hot days (≥ 35 °C) in June. In the early June, this part of the country would have 0.5 hot days on an average (Table 1), with 0.6 days for the mid-June, and 0.8 days for the late part of the month. This part of the country has registered a noticeably increased number of hot days in the late June since 2000.

July is featured with a noticeably raised number of hot days, with 1.5 hot days for the early July (Table 1). The mid-July would have 1.9 hot days on an average, though 2-5 days for the years since 2000. The late July has registered a pattern similar to the mid-July, with 2.2 hot days on an average, and a noticeably increased number of hot days to 2-5 days since 2000.

In August, the lower and middle reaches of the Yangtze River start to see fewer hot days. The early August is averaged with 1.7 hot days, witnessed a noticeably increased number of hot days in a 10-year period. The mid-August would have 1.4 hot days, and the late August 1.2 hot days. Overall speaking, the early August has slightly more high temperature days,

The Influence of Climate Change on Rice in China from 1961 to 2009 123

increasing the multi-cropping index, farmers may face challenges as how to better address the issues related to availability of additional farming machinery required for the enlarged double-cropping rice production. On the other side, as climate will continue to warm, the early rice may be negtively affected by high temperature (≥35 ºC) on filling stage of rice, and therefore it is imperative to develop and use heat-resistant rice varieties to mitigate the high

Fig. 11. The influence of climate change on growing northern boundaries of double-

Cheng S.H., Jian Li, 2007: Rice in China. Jindun Publishing, 90-93

CAY, China Agriculture Yearbook, 2007: China Agriculture Publishing House, 140. (In

CSY. China Statistical Yearbook. 2001: National Bureau of Statistics of China. China Statistics

CSY. China Statistical Yearbook. 2003: National Bureau of Statistics of China. China Statistics

Ding Y., Ren, G., Shi, G., Gong, P., Zheng, D., Zai, P., Zhang, D., Zhao, C., Wang, S., Wang,

H., Luo, Y., Chen, D., Gao, X., Dai, X., 2007. China's National Assessment Report on Climate Change ( I ): Climate change in China and the future trend. Advances in

temperature-induced crop damages.

cropping rice in China from 1961 to 2009.

**5. References**

Chinese)

Press (In Chinese)

Press (In Chinese)

Climate Change Research 3, 1-5.

with an ascending trend in the past decade. The number of hot days steadily declines starting from the mid-August (Table 1).

Table 1. The high temperature days(≥35 °C)for every 10days over Jiangnan and South China regions during 1961-2009.

In summary, the South China has, on an average, 11.8 hot days in the summer, though with a noticeably raised number of hot days since 2000, especially from the late June to the early August. In the past decade, the southern rice growing areas have witnessed a noticeably increased number of hot days in the summer, which may cause heat injury to the rice plants in their filling stage, compromising both the yield and quality of rice. In this context, one has to breed heat resistant rice varieties and develop technical measures to ease the damages caused by high temperature.

#### **4. Conclusion**

Rice is one of China's most important staple food crops, and the climate change have already influenced the growth of rice in China. All the above studies showed that the climate change were influenced the rice planting in southern China. For recent two decades, as the active accumulated temperature increases in the southern China, the rice growth period extended, with the double-cropping rice growing boundaries being apparently pushed northward, even showing a slight northward shit of triple-cropping rice boundaries. From 1960s to 1980s, the double-cropping rice only grew in the areas to the south of the Yangtze River. However, for the recent 10 years, its growth areas had shifted to those to the north of the Yangtze, with their northern boundaries having been pushed approximately 300 km to the north, extending to northeastern part of the Sichuan, eastern Guizhou, Chongqing, most Hubei, central and southern Anhui, as well as southern Jiangsu (Fig.11). Although climate warming increased the thermal resources for rice growth areas over the region, creating favorable conditions for making use the thermal resources, and for increasing the multi-cropping index, farmers may face challenges as how to better address the issues related to availability of additional farming machinery required for the enlarged double-cropping rice production. On the other side, as climate will continue to warm, the early rice may be negtively affected by high temperature (≥35 ºC) on filling stage of rice, and therefore it is imperative to develop and use heat-resistant rice varieties to mitigate the high temperature-induced crop damages.

Fig. 11. The influence of climate change on growing northern boundaries of doublecropping rice in China from 1961 to 2009.

#### **5. References**

Global Warming Impacts – Case Studies on

122 the Economy, Human Health, and on Urban and Natural Environments

with an ascending trend in the past decade. The number of hot days steadily declines

 1961-1970 1971-1980 1981-1990 1991-2000 2001-2009 Jiangnan Jun 1-10 0.3 0.2 0.4 0.3 0.3

> Jun 11-20 0.5 0.6 0.4 0.3 0.8 Jun 21-30 0.8 0.7 0.6 0.7 1.7 July 1-10 1.4 2.5 1.8 1.4 2.8 July 11-20 3.6 2.1 3.3 2.8 3.4 July 21-31 4.3 3.1 2.5 3.8 4.5 Aug 1-10 3.1 3.3 2.6 2.8 2.9 Aug 11-20 2.6 1.4 1.8 1.4 1.8 Aug 21-31 2.7 1.4 1.0 1.1 2.1

> Jun 1-10 0.3 0.2 0.3 0.9 0.4 Jun 11-20 0.4 0.7 0.6 0.5 0.5 Jun 21-30 0.8 0.7 1.0 0.7 1.5 July 1-10 1.1 1.7 1.5 1.2 2.1 July 11-20 1.8 1.9 2.2 1.6 3.0 July 21-31 2.5 1.9 2.1 2.4 3.1 Aug 1-10 1.4 1.2 2.1 1.9 2.7 Aug 11-20 1.4 0.9 1.9 1.4 1.8 Aug 21-31 1.7 0.8 1.2 1.5 1.8

Table 1. The high temperature days(≥35 °C)for every 10days over Jiangnan and South China

In summary, the South China has, on an average, 11.8 hot days in the summer, though with a noticeably raised number of hot days since 2000, especially from the late June to the early August. In the past decade, the southern rice growing areas have witnessed a noticeably increased number of hot days in the summer, which may cause heat injury to the rice plants in their filling stage, compromising both the yield and quality of rice. In this context, one has to breed heat resistant rice varieties and develop technical measures to ease the damages

Rice is one of China's most important staple food crops, and the climate change have already influenced the growth of rice in China. All the above studies showed that the climate change were influenced the rice planting in southern China. For recent two decades, as the active accumulated temperature increases in the southern China, the rice growth period extended, with the double-cropping rice growing boundaries being apparently pushed northward, even showing a slight northward shit of triple-cropping rice boundaries. From 1960s to 1980s, the double-cropping rice only grew in the areas to the south of the Yangtze River. However, for the recent 10 years, its growth areas had shifted to those to the north of the Yangtze, with their northern boundaries having been pushed approximately 300 km to the north, extending to northeastern part of the Sichuan, eastern Guizhou, Chongqing, most Hubei, central and southern Anhui, as well as southern Jiangsu (Fig.11). Although climate warming increased the thermal resources for rice growth areas over the region, creating favorable conditions for making use the thermal resources, and for

starting from the mid-August (Table 1).

South China

regions during 1961-2009.

caused by high temperature.

**4. Conclusion**

**8**

**Climate Change Adaptation using Agroforestry**

Conventional agricultural practices in tropical latitudes, using modern plant breeding techniques, fertilizers, and irrigation, have resulted in an increased grain yield (Huxley, 1999). However, these agricultural practices have also played a major role in increasing the global total area of marginal land that is now substandard for the long-term production of food and livestock (FAO, 1990), and has contributed significantly to the accumulation of greenhouse gases in the atmosphere (IPCC, 2007). Such activities are most notable in developing countries which are strongly affected by climate change due to their lower capacity to adapt compared to developed nations (IPPC, 2007). Comparatively, developed nations have the infrastructure and financial capabilities to cope more effectively to a

As a result of the inherent environmental degradation and poverty associated with deforestation and conventional agriculture, there is a resurgence in the implementation of sustainable land-use practices including agroforestry (Kandji et al., 2006). In this paper agroforestry is defined as the deliberate integration of woody species with agricultural crops and/or pastures on the same land-unit resulting in the integration of economical and ecological interactions between components (Young, 2002). The cultivation of trees in combination with agricultural crops was a common practice dating back to the beginning of plant and animal domestication. Since then, several models of various agroforesry practices, from Asia, Africa and Europe to North and South America, have been developed (King, 1987). In tropical latitudes, farmers imitated vertical forest structure and diversity by planting a variety of crops with different growth habits. It was not unusual to plant up to 24 species on a plot one-tenth of a hectare with each layer corresponding to the natural stratification of a tropical forest (King, 1987). Until the 1860s, the focus of agroforestry practices was on tree production. It was not until 1975, when the International Development Research Centre (IDRC) in Canada concluded that priority in research should be given to combined agroforestry production systems in tropical regions in order to optimize land-use, establish food security, and address the increasing problem of environmental degradation (King, 1987). Since then, agroforestry practices were promoted as a sustainable land-use management system in developed and developing countries. For example, agroforestry practices range from low-input systems such as alley cropping and short-term improved fallow with leguminous shrubs to shade-grown coffee (*Coffea arabica* L.) in tropical regions and high-input cereal-legume systems and riparian plantings in temperate biomes (Nair,

**1. Introduction**

changing climate.

1993; Gordon & Newman, 1997).

**Practices: A Case Study from Costa Rica**

Maren Oelbermann and Carolyn E. Smith

*University of Waterloo*

*Canada*

### **Climate Change Adaptation using Agroforestry Practices: A Case Study from Costa Rica**

Maren Oelbermann and Carolyn E. Smith *University of Waterloo Canada*

#### **1. Introduction**

Global Warming Impacts – Case Studies on

124 the Economy, Human Health, and on Urban and Natural Environments

Foley, J.A., R. DeFries, G.P. Asner, C. Barford, G. Bonan, S.R. Carpenter, F.S. Chapin, M.T. Coe and Co-author, 2005: Global consequences of land use. Science, 309,570-574 Olesen, J.E., M. Bindi.Consequences of climate change for European agriculture

Zhang Y., F T Wang, 1998: On the possible impacts of climate warming on rice production in

productivity, land use and policy. Eur.J.Agron,2002,16: 239-262

China. Acta Meteorologica Sinica, 56(3), 369-376

Conventional agricultural practices in tropical latitudes, using modern plant breeding techniques, fertilizers, and irrigation, have resulted in an increased grain yield (Huxley, 1999). However, these agricultural practices have also played a major role in increasing the global total area of marginal land that is now substandard for the long-term production of food and livestock (FAO, 1990), and has contributed significantly to the accumulation of greenhouse gases in the atmosphere (IPCC, 2007). Such activities are most notable in developing countries which are strongly affected by climate change due to their lower capacity to adapt compared to developed nations (IPPC, 2007). Comparatively, developed nations have the infrastructure and financial capabilities to cope more effectively to a changing climate.

As a result of the inherent environmental degradation and poverty associated with deforestation and conventional agriculture, there is a resurgence in the implementation of sustainable land-use practices including agroforestry (Kandji et al., 2006). In this paper agroforestry is defined as the deliberate integration of woody species with agricultural crops and/or pastures on the same land-unit resulting in the integration of economical and ecological interactions between components (Young, 2002). The cultivation of trees in combination with agricultural crops was a common practice dating back to the beginning of plant and animal domestication. Since then, several models of various agroforesry practices, from Asia, Africa and Europe to North and South America, have been developed (King, 1987). In tropical latitudes, farmers imitated vertical forest structure and diversity by planting a variety of crops with different growth habits. It was not unusual to plant up to 24 species on a plot one-tenth of a hectare with each layer corresponding to the natural stratification of a tropical forest (King, 1987). Until the 1860s, the focus of agroforestry practices was on tree production. It was not until 1975, when the International Development Research Centre (IDRC) in Canada concluded that priority in research should be given to combined agroforestry production systems in tropical regions in order to optimize land-use, establish food security, and address the increasing problem of environmental degradation (King, 1987). Since then, agroforestry practices were promoted as a sustainable land-use management system in developed and developing countries. For example, agroforestry practices range from low-input systems such as alley cropping and short-term improved fallow with leguminous shrubs to shade-grown coffee (*Coffea arabica* L.) in tropical regions and high-input cereal-legume systems and riparian plantings in temperate biomes (Nair, 1993; Gordon & Newman, 1997).

Climate Change Adaptation using Agroforestry Practices: A Case Study from Costa Rica 127

Verchot et al. (2007) suggested that agroforestry practices, apart from providing ecosystem services, are a means of diversifying agricultural production and increase food security for smallholder agricultural producers, especially under current climate change scenarios. For example, recent observations on inter-annual changes in temperature and precipitation along Costa Rica's Pacific coast have shown more intense and longer dry seasons, coinciding with changes predicted by the IPCC in this region (IPCC, 2007). Although maintaining agricultural productivity under changing climatic conditions will be challenging (Watson et al., 2000), Sanchez (2000) suggested that structurally and functionally complex agroecosystem management systems, including agroforestry practices, may show a greater resilience to changing environmental conditions. Although several studies have been published on the adoption of agroforestry practices (Pattanayak et al., 2003; Mercer, 2004), few studies have investigated the efficacy of agroforestry as an agroecosystem management practice with greater resilience to climate change compared to less diversified (conventional) agroecosystems. Verchot et al. (2007) noted that the contribution of agroforestry practices to buffer against climate shifts is currently not well understood. Such knowledge is of great importance because agroforestry is also considered as a key player in achieving the Millennium Development Goals as described in the United Nations annual report (Verchot et al., 2007). The goal of this research was to present a case study from Costa Rica that evaluated the knowledge and perception of agricultural producers on climate change. This study also evaluated the implementation of agroforestry practices as a strategy to climate

The research area and agricultural producers described in this paper corresponded to those currently under evaluation by the GEF-Silvopastoral Study (Pagiola et al., 2007; Yamamoto et al., 2007; Pagiola et al., 2008; Hänsela et al., 2009). The Silvopastoral Approaches for Ecosystem Management, or Global Environment Facility-Silvopastoral Study (GEF-Silvopastoral Study), is a pilot project that was initiated in 2002 in rural Nicaragua, Costa Rica and Colombia where degraded pastures were prevalent. Land owners participating in the project received payment for the ecological services they generated including the integration of trees on their land, improvement of pasture management, maintaining habitat for biodiversity conservation, enhancing soil and water conservation, and increasing carbon sequestration. In association with the Global Environment Facility, the World Bank, the Regional Integrated Silvopastoral Management Project (RISEMAP) and researchers from the Tropical Agricultural Research and Higher Education Center (CATIE) in Costa Rica, each participating agricultural producer was surveyed to determine baseline data and the type of already existing or new agroforestry practices, that ultimately provided ecological services, they were interested in implementing. Financial incentives were received over a four-year period, and were based on the type and increment of ecological services they implemented

The GEF Silvopastoral study and our study was conducted surrounding the area of Esparza (09°59'N, 84°38'W), located in the Central Pacific Coastal region of Costa Rica. The study area surrounding Esparza encompassed 432 km2, with land-use consisting predominantly of mixed-agricultural production under conventional practices with beef, dairy, rice, sugarcane, and fruit. The majority of agricultural producers in this area have a beef-dairy production (62%), followed by beef (20%), mixed crop-livestock (14%), and beef/dairy

relative to the previously collected baseline data (Pagiola et al., 2008).

change adaptation.

breeding stock production (8%).

**2. Study site**

In Central America, agroforestry practices were also diverse and commonly included a combination of trees with food crops, trees with livestock (pasture for fodder) or all elements combined (Budowski, 1987). In this region, pre-Columbian people mixed trees with food crops in a system similar to shifting cultivation. Other land-use techniques included home gardens and the integration of trees and crops along banks. Agroforestry practices in Central America were first described by O.F. Cook in a 1901 report to the U.S. Department of Agriculture, noting that coffee plants were growing under shade trees. Cook also noted the beneficial effects of leguminous shade trees on soil fertility. Since then there has been a plethora of information published on Central American, particularly Costa Rican agroforestry practices. For example, Holdridge reported on the practice of planting *Alnus acuminate* Kunth. in pastures in the Costa Rican highlands (Holdridge, et al. 1977). Budowski (1987) noted the use of *Cupressus lusitanica* L. windbreaks in the highlands and the use of *Cordial alliodora* L. in lowland pastures in Costa Rica. Other research from Costa Rica reported secondary forest management on abandoned coffee plantations (Budowski, 1987), and use of life-fences and increased biodiversity (Harvey et al., 2005). Alley cropping was established in Costa Rica as a new agroforestry practice in the early 1980s, where crops were grown between rows of trees (Kass et al. 1995). The aim of this modern agroforestry practice was to minimize the need for external nutrient inputs from fertilizers or manure, which are difficult or not economically feasible for small producers. Instead this agroforestry practice relied on the biannual input of organic material derived from leguminous plants, high in nutrient content, of completely shoot pruned of trees. The application of the organic material to the soil as mulch was synchronized with the seeding of crops, resulting in the maximum release of nutrients from the decomposing organic material to the growing crops. Over the past decade the potential of agroforestry systems to sequester carbon (Oelbermann et al., 2004; Oelbermann & Voroney, 2011), and their role in providing ecosystem services (Pagiola et al., 2008) has become the forefront of research as a result of global climate change.

Agroforestry systems are unique because they are a land management practice that simultaneously addresses biophysical, economical, and socio-ecological components. Such diversity and interactions leads to a greater functional and structural complexity compared to conventional agroeosystems (Nair, 1993). Leaky & Simmons (1996) suggested that over the long-term agroforestry systems become successively similar to natural systems, where biodiversity increases with each stage in the development of this succession. Such functional and structural complexity has led to the great diversity currently observed in modern agroforestry practices.

However, the adoption of agroforestry practices is based on socio-cultural and sociecological considerations including land tenure and land rights, in addition to providing enhanced biodiversity and ecological services (McGinty et al. 2008; Sood & Mitchell 2009). Currently, agroforestry practices are increasingly adopted due to their potential of providing ecosystem services. Ecosystem services not only provide an economic incentive but are also of value to society by maintaining environmental sustainability (FAO, 2007). The benefits derived from agroforestry practices occur over a range of spatial and temporal scales (Jose, 2009). For example, when comparing the large-scale removal of trees due to deforestation and its resultant high levels of erosion, agroforestry systems provide ecological services by decreasing soil erosion and preventing the sedimentation of waterways; ultimately protecting downstream fisheries (Pearce & Mourato 2004). Thus, ecological services provided by agroforestry systems are derived at the farm- and / or landscape-scale but are enjoyed by society at regional- and / or global-scales (Jose, 2009).

Verchot et al. (2007) suggested that agroforestry practices, apart from providing ecosystem services, are a means of diversifying agricultural production and increase food security for smallholder agricultural producers, especially under current climate change scenarios. For example, recent observations on inter-annual changes in temperature and precipitation along Costa Rica's Pacific coast have shown more intense and longer dry seasons, coinciding with changes predicted by the IPCC in this region (IPCC, 2007). Although maintaining agricultural productivity under changing climatic conditions will be challenging (Watson et al., 2000), Sanchez (2000) suggested that structurally and functionally complex agroecosystem management systems, including agroforestry practices, may show a greater resilience to changing environmental conditions. Although several studies have been published on the adoption of agroforestry practices (Pattanayak et al., 2003; Mercer, 2004), few studies have investigated the efficacy of agroforestry as an agroecosystem management practice with greater resilience to climate change compared to less diversified (conventional) agroecosystems. Verchot et al. (2007) noted that the contribution of agroforestry practices to buffer against climate shifts is currently not well understood. Such knowledge is of great importance because agroforestry is also considered as a key player in achieving the Millennium Development Goals as described in the United Nations annual report (Verchot et al., 2007). The goal of this research was to present a case study from Costa Rica that evaluated the knowledge and perception of agricultural producers on climate change. This study also evaluated the implementation of agroforestry practices as a strategy to climate change adaptation.

#### **2. Study site**

Global Warming Impacts – Case Studies on

126 the Economy, Human Health, and on Urban and Natural Environments

In Central America, agroforestry practices were also diverse and commonly included a combination of trees with food crops, trees with livestock (pasture for fodder) or all elements combined (Budowski, 1987). In this region, pre-Columbian people mixed trees with food crops in a system similar to shifting cultivation. Other land-use techniques included home gardens and the integration of trees and crops along banks. Agroforestry practices in Central America were first described by O.F. Cook in a 1901 report to the U.S. Department of Agriculture, noting that coffee plants were growing under shade trees. Cook also noted the beneficial effects of leguminous shade trees on soil fertility. Since then there has been a plethora of information published on Central American, particularly Costa Rican agroforestry practices. For example, Holdridge reported on the practice of planting *Alnus acuminate* Kunth. in pastures in the Costa Rican highlands (Holdridge, et al. 1977). Budowski (1987) noted the use of *Cupressus lusitanica* L. windbreaks in the highlands and the use of *Cordial alliodora* L. in lowland pastures in Costa Rica. Other research from Costa Rica reported secondary forest management on abandoned coffee plantations (Budowski, 1987), and use of life-fences and increased biodiversity (Harvey et al., 2005). Alley cropping was established in Costa Rica as a new agroforestry practice in the early 1980s, where crops were grown between rows of trees (Kass et al. 1995). The aim of this modern agroforestry practice was to minimize the need for external nutrient inputs from fertilizers or manure, which are difficult or not economically feasible for small producers. Instead this agroforestry practice relied on the biannual input of organic material derived from leguminous plants, high in nutrient content, of completely shoot pruned of trees. The application of the organic material to the soil as mulch was synchronized with the seeding of crops, resulting in the maximum release of nutrients from the decomposing organic material to the growing crops. Over the past decade the potential of agroforestry systems to sequester carbon (Oelbermann et al., 2004; Oelbermann & Voroney, 2011), and their role in providing ecosystem services (Pagiola et al., 2008) has become the forefront of research as a result of global climate

Agroforestry systems are unique because they are a land management practice that simultaneously addresses biophysical, economical, and socio-ecological components. Such diversity and interactions leads to a greater functional and structural complexity compared to conventional agroeosystems (Nair, 1993). Leaky & Simmons (1996) suggested that over the long-term agroforestry systems become successively similar to natural systems, where biodiversity increases with each stage in the development of this succession. Such functional and structural complexity has led to the great diversity currently observed in modern

However, the adoption of agroforestry practices is based on socio-cultural and sociecological considerations including land tenure and land rights, in addition to providing enhanced biodiversity and ecological services (McGinty et al. 2008; Sood & Mitchell 2009). Currently, agroforestry practices are increasingly adopted due to their potential of providing ecosystem services. Ecosystem services not only provide an economic incentive but are also of value to society by maintaining environmental sustainability (FAO, 2007). The benefits derived from agroforestry practices occur over a range of spatial and temporal scales (Jose, 2009). For example, when comparing the large-scale removal of trees due to deforestation and its resultant high levels of erosion, agroforestry systems provide ecological services by decreasing soil erosion and preventing the sedimentation of waterways; ultimately protecting downstream fisheries (Pearce & Mourato 2004). Thus, ecological services provided by agroforestry systems are derived at the farm- and / or landscape-scale but are enjoyed by society at regional- and / or global-scales (Jose, 2009).

change.

agroforestry practices.

The research area and agricultural producers described in this paper corresponded to those currently under evaluation by the GEF-Silvopastoral Study (Pagiola et al., 2007; Yamamoto et al., 2007; Pagiola et al., 2008; Hänsela et al., 2009). The Silvopastoral Approaches for Ecosystem Management, or Global Environment Facility-Silvopastoral Study (GEF-Silvopastoral Study), is a pilot project that was initiated in 2002 in rural Nicaragua, Costa Rica and Colombia where degraded pastures were prevalent. Land owners participating in the project received payment for the ecological services they generated including the integration of trees on their land, improvement of pasture management, maintaining habitat for biodiversity conservation, enhancing soil and water conservation, and increasing carbon sequestration. In association with the Global Environment Facility, the World Bank, the Regional Integrated Silvopastoral Management Project (RISEMAP) and researchers from the Tropical Agricultural Research and Higher Education Center (CATIE) in Costa Rica, each participating agricultural producer was surveyed to determine baseline data and the type of already existing or new agroforestry practices, that ultimately provided ecological services, they were interested in implementing. Financial incentives were received over a four-year period, and were based on the type and increment of ecological services they implemented relative to the previously collected baseline data (Pagiola et al., 2008).

The GEF Silvopastoral study and our study was conducted surrounding the area of Esparza (09°59'N, 84°38'W), located in the Central Pacific Coastal region of Costa Rica. The study area surrounding Esparza encompassed 432 km2, with land-use consisting predominantly of mixed-agricultural production under conventional practices with beef, dairy, rice, sugarcane, and fruit. The majority of agricultural producers in this area have a beef-dairy production (62%), followed by beef (20%), mixed crop-livestock (14%), and beef/dairy breeding stock production (8%).

Climate Change Adaptation using Agroforestry Practices: A Case Study from Costa Rica 129

change on current agricultural production; 4) the type of agroforestry practice implemented and its outcome; and 5) why agroforestry practices were adopted. In order to evaluate the adaptive capacity of agricultural producers to climate change, and to contextualize how landowners perceived climate change, the survey included questions on changes in crop and livestock productivity, diseases and pests; changes in the amount and intensity of ambient rainfall and temperature, onset of rainy and dry seasons, frequency of droughts and how agroforestry practices helped to manage droughts. Additionally, landowners were also asked what strategies they were currently using to adapt to climate change and what their incentives (e.g. environmental, financial, extension support) were for implementing agroforestry practices. The semi-structured interviews lasted between 1-3 hours and each

The surveys were developed and conducted in association with a representative from the Costa Rican Ministry of Agriculture as well as rural extension officers and researchers from CATIE. Details of the survey questions are presented in Smith (2008). Textual data included information provided by agricultural producers that elaborated on the questions of the survey. Recorded interview data was fully transcribed and organized manually into the different themes. In order to understand how the different themes are interconnected, each individual theme was analyzed using QSR NVivo® software (QSR International, Melbourne, Australia). This was done by counting who said what within each theme. Nodes and memos were created using NVIVO to mark relevant concepts, topics and themes. The model explorer tool in NVIVO was used to diagrammatically map out how the themes

Results from this study only incorporated agricultural producers with the greatest experience (more than 30 years) in farming because these participants were more likely to notice changes in climate. The majority of these producers (90%) understood the concept of climate change and its cause. Approximately 80% of those surveyed understood that climate change is currently impacting and will impact their land, their family and livelihoods in the future. Similar results were reported by Maddison (2007) who surveyed agricultural producers from 11 different African countries. He found that agriculturalists with the greatest amount of farming experience reported changes in climate. Our results found that many agricultural producers within the study region had knowledge on climate change likely as a consequence of their involvement with the GEF-Silvopastoral Study, and the social networks they established with other agricultural producers, the Costa Rican Ministry of Agriculture, and with researchers and extension personnel from CATIE. Agricultural producers in our survey noted that their primary source of information on climate change was derived from CATIE (56%) and from the Costa Rican Ministry of Agriculture (34%). Information from CATIE and the Costa Rican Ministry of Agriculture was gained through the participation of agricultural producers in organized workshops, seminars and / or on-

Agricultural producers interviewed in this study observed several changes in climate, particularly relating to increased ambient temperatures and a prolonged dry season, in the Esparza region over the past 30 years and how this may potentially have affected agricultural productivity (Table 1). Approximately 90% of the agricultural producers noticed

interview was recorded.

related to each other.

farm visits.

**4. Results and discussion**

**4.1 Producer perception and understanding of climate change**

The area surrounding Esparza was characterized as a sub-humid tropical forest zone. The average annual temperature was 27.9°C and the mean annual daytime temperature was 32°C and the mean annual nighttime temperature was 22°C (Figure 1). The average annual precipitation of this region was ~1599 mm, with a distinct dry season from December to April and a distinct wet season from May to November. The mean number of sunshine hours in this region was 10 h/day from November to April, and 6 h/day from May to October. This area had a relative humidity ranging from 65% during the dry season and 80% in the wet season. This region is also influenced by large-scale inter-annual fluctuations such as the El Niño or La Niña. The elevation above sea level ranges from 50 m near the Pacific coast to 1000 m in inland areas. The geology of this region was based upon volcanic origin and alluvial sedimentation. This led to the development of Nitisols, with a predominantly loamy texture. The soils of the region were dark red, brown or yellow in color with the presence of an agrillic B horizon, but lack ferric and vertic properties.

Fig. 1. Mean monthly maximum and minimum temperature (line graph) over 41 years and mean monthly precipitation (bar graph) over 64 years for Esparza, Costa Rica.

#### **3. Sampling methods and statistical analysis**

Agricultural producers that participated in this study were chosen because of their existing participation in the GEF-Silvopastoral Study. As such, the participating agricultural producers were already informed about climate change, ecological services, and payment for such services through interaction with CATIE researchers and extension personnel. In addition to conducting interviews with agricultural producers in association with CATIE rural extension officers and the Costa Rican Ministry of Agriculture, further information for this study was obtained from an existing database collected by the GEF-Silvopastoral Study. Information from this database, such as land biophysical characteristics and the type of agroforestry practices implemented provided more depth to the interviews conducted in our study.

In 2007, a total of 50 out of 105 agricultural producers were randomly chosen for our study; and were asked questions based on the following themes: 1) background and farming experience based on information not already collected by the GEF-Silvopastoral Study; 2) knowledge and perceptions about climate change; 3) knowledge on the effects of climate change on current agricultural production; 4) the type of agroforestry practice implemented and its outcome; and 5) why agroforestry practices were adopted. In order to evaluate the adaptive capacity of agricultural producers to climate change, and to contextualize how landowners perceived climate change, the survey included questions on changes in crop and livestock productivity, diseases and pests; changes in the amount and intensity of ambient rainfall and temperature, onset of rainy and dry seasons, frequency of droughts and how agroforestry practices helped to manage droughts. Additionally, landowners were also asked what strategies they were currently using to adapt to climate change and what their incentives (e.g. environmental, financial, extension support) were for implementing agroforestry practices. The semi-structured interviews lasted between 1-3 hours and each interview was recorded.

The surveys were developed and conducted in association with a representative from the Costa Rican Ministry of Agriculture as well as rural extension officers and researchers from CATIE. Details of the survey questions are presented in Smith (2008). Textual data included information provided by agricultural producers that elaborated on the questions of the survey. Recorded interview data was fully transcribed and organized manually into the different themes. In order to understand how the different themes are interconnected, each individual theme was analyzed using QSR NVivo® software (QSR International, Melbourne, Australia). This was done by counting who said what within each theme. Nodes and memos were created using NVIVO to mark relevant concepts, topics and themes. The model explorer tool in NVIVO was used to diagrammatically map out how the themes related to each other.

#### **4. Results and discussion**

Global Warming Impacts – Case Studies on

128 the Economy, Human Health, and on Urban and Natural Environments

The area surrounding Esparza was characterized as a sub-humid tropical forest zone. The average annual temperature was 27.9°C and the mean annual daytime temperature was 32°C and the mean annual nighttime temperature was 22°C (Figure 1). The average annual precipitation of this region was ~1599 mm, with a distinct dry season from December to April and a distinct wet season from May to November. The mean number of sunshine hours in this region was 10 h/day from November to April, and 6 h/day from May to October. This area had a relative humidity ranging from 65% during the dry season and 80% in the wet season. This region is also influenced by large-scale inter-annual fluctuations such as the El Niño or La Niña. The elevation above sea level ranges from 50 m near the Pacific coast to 1000 m in inland areas. The geology of this region was based upon volcanic origin and alluvial sedimentation. This led to the development of Nitisols, with a predominantly loamy texture. The soils of the region were dark red, brown or yellow in color with the

Fig. 1. Mean monthly maximum and minimum temperature (line graph) over 41 years and

Agricultural producers that participated in this study were chosen because of their existing participation in the GEF-Silvopastoral Study. As such, the participating agricultural producers were already informed about climate change, ecological services, and payment for such services through interaction with CATIE researchers and extension personnel. In addition to conducting interviews with agricultural producers in association with CATIE rural extension officers and the Costa Rican Ministry of Agriculture, further information for this study was obtained from an existing database collected by the GEF-Silvopastoral Study. Information from this database, such as land biophysical characteristics and the type of agroforestry practices implemented provided more depth to the interviews conducted in

In 2007, a total of 50 out of 105 agricultural producers were randomly chosen for our study; and were asked questions based on the following themes: 1) background and farming experience based on information not already collected by the GEF-Silvopastoral Study; 2) knowledge and perceptions about climate change; 3) knowledge on the effects of climate

mean monthly precipitation (bar graph) over 64 years for Esparza, Costa Rica.

**3. Sampling methods and statistical analysis**

our study.

presence of an agrillic B horizon, but lack ferric and vertic properties.

#### **4.1 Producer perception and understanding of climate change**

Results from this study only incorporated agricultural producers with the greatest experience (more than 30 years) in farming because these participants were more likely to notice changes in climate. The majority of these producers (90%) understood the concept of climate change and its cause. Approximately 80% of those surveyed understood that climate change is currently impacting and will impact their land, their family and livelihoods in the future. Similar results were reported by Maddison (2007) who surveyed agricultural producers from 11 different African countries. He found that agriculturalists with the greatest amount of farming experience reported changes in climate. Our results found that many agricultural producers within the study region had knowledge on climate change likely as a consequence of their involvement with the GEF-Silvopastoral Study, and the social networks they established with other agricultural producers, the Costa Rican Ministry of Agriculture, and with researchers and extension personnel from CATIE. Agricultural producers in our survey noted that their primary source of information on climate change was derived from CATIE (56%) and from the Costa Rican Ministry of Agriculture (34%). Information from CATIE and the Costa Rican Ministry of Agriculture was gained through the participation of agricultural producers in organized workshops, seminars and / or onfarm visits.

Agricultural producers interviewed in this study observed several changes in climate, particularly relating to increased ambient temperatures and a prolonged dry season, in the Esparza region over the past 30 years and how this may potentially have affected agricultural productivity (Table 1). Approximately 90% of the agricultural producers noticed

Climate Change Adaptation using Agroforestry Practices: A Case Study from Costa Rica 131

As a result of the payment for ecological services (PES) program through the GEF-Silvopastoral Study, agricultural producers participating in our study had implemented a variety of agroforestry practices, including silvopasture with *Brachiaria brizantha* (Hochst. Ex A. Rich) Stapf. grass, fodderbanks, integration of trees on farmland or farmyards, and the establishment of live fences, that aided their adaptation to climate change. They were also aware that such activities helped in mitigating methane emissions from cattle and significantly increased the amount of carbon captured and stored for the long-term in trees and in soil. A total of 96% of the agricultural producers surveyed integrated trees on their land (Table 2). Specifically, agricultural producers adopted different strategies in order to

> **Implementation by Landowners (%)**

**4.2 Adaptation and implementation of agroforestry systems**

cope with a longer and more intense dry season.

Maintenance/implementation of trees on

**Change Adaptation Strategy**

Costa Rica (n=50).

their land (Table 3).

**Agroforestry Land management Practice as a Climate**

Silvipasture with *Brachiaria brizantha* 100

farmland/farmyard <sup>96</sup> Fodder banks 56 Live fences 80 Shade for pasture grass and livestock 98 Enhanced nutrient cycling 98 Soil and water conservation 96 Fuelwood 100 Fruit production 69

Table 2. Percentage of agricultural producers implementing agroforestry land management practices as an adaptation strategy to a more intense dry season, and indicated other benefits (ecological services) as a result of implementing trees on their land in Esparza,

For example, 100% of the agricultural producers in our study adapted *B. brizantha* as an improved pasture grass species when they initiated agroforestry silvopastural practices. *Brachiaria brizantha* is native to the African continent but it has been integrated in other tropical areas outside of its native range for use in permanent pasture, cutting for fresh feed, and as a ground cover for erosion control (Barnes et al. 2007). This grass species grows on a wide variety of soil types ranging from light to heavy soil textures and can tolerate a wide range in soil pH (4 to 8). *Brachiaria brizantha* is well adapted to a dry season ranging from 3 to 6 months in length during which time its leaves remain green while native species become dry, brown and unproductive. Additionally, *B. brizantha* can also endure wet soils and grows at an altitude up to 2000 m and thus can tolerate light frost (Barnes et al., 2007). Agricultural producers in our study found many advantages from growing *B. brizantha* on

Producers in our study observed an increase in milk production during the dry season by up to 70% as a result of establishing pastures with *B. brizantha*. Similar results were reported by Holmann et al. (2004) who found that the overall production of milk in Costa Rica increased by 55.5% as a result of establishing pastures or fodder banks with *B. brizantha*. This increase is likely due to the higher protein content in *B. brizantha* compared to other grass species traditionally used in Costa Rica (Cook et al., 2005). Results from our study

increased temperatures while 70% observed a more intense rainy season, but the overall amount of rainfall was lower. An additional 78% of the agricultural producers observed negative impacts on their land, crops, and livestock as a result of a prolonged and more intense dry season including a decrease in crop yield and water availability to livestock and their family. These observations coincided with those predicted by the IPCC (2007), who suggested that the Pacific region of Costa Rica is expected to be drier and hotter. A temperature increase of 0.1°C per decade was reported between the years 1901 and 2005 (IPPC, 2007). According to the IPPC, carbon dioxide (CO2) started to have an effect on Costa Rica's temperature in the 1970s (IPCC, 2007). Walther et al. (2002) noted that Central America is one of the global regions where climate change impacts on the environment will be pronounced and the loss of species with climate change has already been identified. In the future, IPPC Climate models predict a minimum increase in temperature of 1.5°C and a maximum increase of 5.6°C, from current conditions for this region of Central America (IPCC, 2007). Predictions by the IPCC for changes in precipitation range from a decrease by 11 to 38% during the dry season and an increase of 7 to 21% during the wet season from current conditions. Agricultural producers in our study observed that changes in climate may have potentially led to a decrease in livestock weight, lower milk production, and a decrease in yield of their harvestable crops and pasture grasses. They also noted that the overall decrease in farm productivity affected food availability for their families and livestock. A prolonged dry season resulted in drought leading to a reduction of the farm's carrying capacity, thereby affecting the number of animals, harvestable crops, and the quantity and quality of milk produced. A mixed response, approximately 38% of the agricultural producers, also related climate change to increased pest outbreaks such as locusts (*Schistocera* spp.), ultimately affecting their crop productivity. Others, especially those at the higher elevations, noted an increase in snakes that are commonly found in lowland areas of the Pacific coast. These observations were similar to those reported by Raxworthy et al. (2008) who found that amphibians were moving upslope as a result of a warmer and drier climate at lower elevations.

Table 1. Agricultural producers observation of changes in quantity and / or quality of available food, feed and water potentially linked to the increase of temperatures and prolonged drought over the past 30 years in Esparza, Costa Rica (n=50).

#### **4.2 Adaptation and implementation of agroforestry systems**

Global Warming Impacts – Case Studies on

**Landowner Observation (%)**

130 the Economy, Human Health, and on Urban and Natural Environments

increased temperatures while 70% observed a more intense rainy season, but the overall amount of rainfall was lower. An additional 78% of the agricultural producers observed negative impacts on their land, crops, and livestock as a result of a prolonged and more intense dry season including a decrease in crop yield and water availability to livestock and their family. These observations coincided with those predicted by the IPCC (2007), who suggested that the Pacific region of Costa Rica is expected to be drier and hotter. A temperature increase of 0.1°C per decade was reported between the years 1901 and 2005 (IPPC, 2007). According to the IPPC, carbon dioxide (CO2) started to have an effect on Costa Rica's temperature in the 1970s (IPCC, 2007). Walther et al. (2002) noted that Central America is one of the global regions where climate change impacts on the environment will be pronounced and the loss of species with climate change has already been identified. In the future, IPPC Climate models predict a minimum increase in temperature of 1.5°C and a maximum increase of 5.6°C, from current conditions for this region of Central America (IPCC, 2007). Predictions by the IPCC for changes in precipitation range from a decrease by 11 to 38% during the dry season and an increase of 7 to 21% during the wet season from current conditions. Agricultural producers in our study observed that changes in climate may have potentially led to a decrease in livestock weight, lower milk production, and a decrease in yield of their harvestable crops and pasture grasses. They also noted that the overall decrease in farm productivity affected food availability for their families and livestock. A prolonged dry season resulted in drought leading to a reduction of the farm's carrying capacity, thereby affecting the number of animals, harvestable crops, and the quantity and quality of milk produced. A mixed response, approximately 38% of the agricultural producers, also related climate change to increased pest outbreaks such as locusts (*Schistocera* spp.), ultimately affecting their crop productivity. Others, especially those at the higher elevations, noted an increase in snakes that are commonly found in lowland areas of the Pacific coast. These observations were similar to those reported by Raxworthy et al. (2008) who found that amphibians were moving upslope as a result of a

> **Potential Changes in Farm Production Quantity and / or Quality**

Overall decrease in water availability for

Table 1. Agricultural producers observation of changes in quantity and / or quality of available food, feed and water potentially linked to the increase of temperatures and

prolonged drought over the past 30 years in Esparza, Costa Rica (n=50).

Overall decrease in farm productivity 72 Decrease in food production 76 Livestock weight loss 80 Decreased milk production 72 Loss of harvestable products 38

Decreased forage production 72 Loss of livestock 76 Loss of harvestable products 46 Decreased milk production 74 Decrease in water levels 64

livestock, crops, and people <sup>54</sup>

warmer and drier climate at lower elevations.

**Climate Characteristics**

**Increased Ambient Temperatures (IPCC, 2007)**

**Prolonged Dry Season (IPCC, 2007)** As a result of the payment for ecological services (PES) program through the GEF-Silvopastoral Study, agricultural producers participating in our study had implemented a variety of agroforestry practices, including silvopasture with *Brachiaria brizantha* (Hochst. Ex A. Rich) Stapf. grass, fodderbanks, integration of trees on farmland or farmyards, and the establishment of live fences, that aided their adaptation to climate change. They were also aware that such activities helped in mitigating methane emissions from cattle and significantly increased the amount of carbon captured and stored for the long-term in trees and in soil. A total of 96% of the agricultural producers surveyed integrated trees on their land (Table 2). Specifically, agricultural producers adopted different strategies in order to cope with a longer and more intense dry season.

Table 2. Percentage of agricultural producers implementing agroforestry land management practices as an adaptation strategy to a more intense dry season, and indicated other benefits (ecological services) as a result of implementing trees on their land in Esparza, Costa Rica (n=50).

For example, 100% of the agricultural producers in our study adapted *B. brizantha* as an improved pasture grass species when they initiated agroforestry silvopastural practices. *Brachiaria brizantha* is native to the African continent but it has been integrated in other tropical areas outside of its native range for use in permanent pasture, cutting for fresh feed, and as a ground cover for erosion control (Barnes et al. 2007). This grass species grows on a wide variety of soil types ranging from light to heavy soil textures and can tolerate a wide range in soil pH (4 to 8). *Brachiaria brizantha* is well adapted to a dry season ranging from 3 to 6 months in length during which time its leaves remain green while native species become dry, brown and unproductive. Additionally, *B. brizantha* can also endure wet soils and grows at an altitude up to 2000 m and thus can tolerate light frost (Barnes et al., 2007). Agricultural producers in our study found many advantages from growing *B. brizantha* on their land (Table 3).

Producers in our study observed an increase in milk production during the dry season by up to 70% as a result of establishing pastures with *B. brizantha*. Similar results were reported by Holmann et al. (2004) who found that the overall production of milk in Costa Rica increased by 55.5% as a result of establishing pastures or fodder banks with *B. brizantha*. This increase is likely due to the higher protein content in *B. brizantha* compared to other grass species traditionally used in Costa Rica (Cook et al., 2005). Results from our study

Climate Change Adaptation using Agroforestry Practices: A Case Study from Costa Rica 133

(96%) of agricultural producers surveyed in our study implemented and maintained trees on their farmland or in the farmyard. Tree species most commonly established on farmland or in farm yards in our study included *Ficus hartwegii* (Miq.) Miq., *Guazuma ulmifolia* Lam., *Dipteryx panamensis* (Pittier) Rec. & Mell, *Enterolobium cyclocarpum* Jacq. Griseb., *Mangifera indica* L., *Byrsonima crassifolia* (L.) Kunth, *Psidium friedrichsthalianum* (O. Berg) Nied., *Gliricidia sepium* (Jacq.) Walp., and *Acrocomia aculeate* (Jacq.) Lodd. Ex Mart. Agricultural producers found that these trees served multiple functions such as the production of fruit for livestock and human consumption (69%), and the production of leaves for livestock fodder. They also expressed the hardiness of these trees during the dry season and as such did not shed their leaves. Other valuable services these trees provided included fuel wood (100%), shade for pasture grass and livestock, and enhanced nutrient cycling (98%), and soil

Another agroforestry practice commonly implemented by participants in the GEF-Silvopastoral Study and widely used in Costa Rica included the use of live fences. In our study, all (100%) farmers surveyed implemented live fences and in a previous study by Harvey et al. (2005) over 80% of the agricultural producers surveyed in Costa Rica implemented live fences. In our study, the most common use of live fences was to provide an economical enclosure for livestock, and separating pastures from roads, forested areas, and waterways. Our study participants also observed that live fences provided shade for livestock and pasture grasses. In addition, many of the agricultural producers interviewed believed that live fences provided an ecological service by conserving biodiversity in addition to preventing soil erosion and protecting streams when they are used to separate pastureland from waterways. Live fences also provided foliage for cattle fodder. However, in our study, none of the agricultural producers surveyed discussed the use of live fences for this purpose. Similarly, Harvey et al. (2005) noted in their study that only 10% of Costa Rican agricultural producers used live fences for the production of fodder in addition to their use as an enclosure for pasture lands. This suggested that agricultural producers in Costa Rica were not aware of all possible benefits of live fences, but those that participated in the GEF-Silvopastoral Study had a greater knowledge on the diverse utility of live fences. Other studies also revealed that the conversion of farmland previously containing few or no trees into areas dominated by agroforestry decreased the amount of degraded land by 15% over a 3-year period (Zamora-Lopez, 2006). Zamora-Lopez (2006) also found that the poorest agricultural producers were able to reduce pastureland degradation by introducing improved pasture with trees, by adopting fodder banks, and live fences. As such, a diversification in agricultural production systems included the implementation of a significant tree component that may buffer against income risks associated with current and future shifts in climate (Verchot et al., 2007). Kandji et al. (2006) also pointed out that agroforestry systems have the ability to improve the microclimate which in turn improves the adaptive capacity of land owners to climate change. Additionally, Kandji et al. (2006) suggested that the presence of trees in agricultural croplands can provide agricultural producers with an additional source of income that helps to strengthen their socioeconomic resilience. For example, tree products including fodder, resins, timber, and fruits provide a

higher source of income than corps, and can also buffer against crop failure.

According to the IPCC (2007) introducing a contingency plan to cope with unexpected changes in climate will increase food security and reduce financial losses. Our study showed that 28% of the agricultural producers researched the issue of climate change in detail and

**4.3 Producer contingency plans and adaptive capacity**

and water conservation (96%).

showed that replacing conventional pasture grass with *B. brizantha* resulted in an improved management practice of grasslands, and also lowered grazing pressure and increased livestock carrying capacity, while at the same time provided a strategy to adapt to a changing climate. For example, Cameron (2002) observed that the implementation of *B. brizantha* grass into pastures resulted in soil and water conservation through a decrease in soil compaction and a reduction in external nutrient inputs.

Table 3. Benefits observed by agricultural producers by integrating silvopasture with *B. brizantha* grass in Esparza, Costa Rica (n=50).

Fig. 2. Fodderbank with *Gliricidia sepium* (Jacq.) Walp. The trees in the foreground show they were recently completely shoot pruned as fodder for livestock, and are already re-sprouting. Photo used with permission from M. Oelbermann.

Fodderbanks were another adaptive measure to climate change implemented by agricultural producers in our study (Figure 2). For example, a total of 56% of the agricultural producers surveyed used fodderbanks with commonly used tree species such as *Gliricidia sepium* (Jacq.) Walp. Pagiola et al. (2008) observed that adaptation of fodderbanks surrounding Esparza was much larger than that compared to other areas of Costa Rica, where they were virtually non-existent. This suggested that the integration of fodderbanks as an additional management practice was due to the close interaction between the agricultural producers, the Costa Rican Ministry of Agriculture, and CATIE researchers and extension officers taking part in the GEF-Silvopastoral Study. Agricultural producers found that *B. brizantha* fodderbanks helped to maintain livestock productivity during years with lower forage biomass and during drought or extended dry periods. A large proportion

**(%)**

132 the Economy, Human Health, and on Urban and Natural Environments

showed that replacing conventional pasture grass with *B. brizantha* resulted in an improved management practice of grasslands, and also lowered grazing pressure and increased livestock carrying capacity, while at the same time provided a strategy to adapt to a changing climate. For example, Cameron (2002) observed that the implementation of *B. brizantha* grass into pastures resulted in soil and water conservation through a decrease in

Reduced erosion 96 Greater drought resistance 100 Increased forage production during dry season 98 Increased number of livestock per unit area 100 Livestock weight maintenance 92 Increased livestock meat and / or milk production 92 Improved calf health 96

Table 3. Benefits observed by agricultural producers by integrating silvopasture with *B.*

Fig. 2. Fodderbank with *Gliricidia sepium* (Jacq.) Walp. The trees in the foreground show they were recently completely shoot pruned as fodder for livestock, and are already re-sprouting.

Fodderbanks were another adaptive measure to climate change implemented by agricultural producers in our study (Figure 2). For example, a total of 56% of the agricultural producers surveyed used fodderbanks with commonly used tree species such as *Gliricidia sepium* (Jacq.) Walp. Pagiola et al. (2008) observed that adaptation of fodderbanks surrounding Esparza was much larger than that compared to other areas of Costa Rica, where they were virtually non-existent. This suggested that the integration of fodderbanks as an additional management practice was due to the close interaction between the agricultural producers, the Costa Rican Ministry of Agriculture, and CATIE researchers and extension officers taking part in the GEF-Silvopastoral Study. Agricultural producers found that *B. brizantha* fodderbanks helped to maintain livestock productivity during years with lower forage biomass and during drought or extended dry periods. A large proportion

**Benefits Observed from** *B. brizantha* **Landowner Observation**

soil compaction and a reduction in external nutrient inputs.

*brizantha* grass in Esparza, Costa Rica (n=50).

Photo used with permission from M. Oelbermann.

(96%) of agricultural producers surveyed in our study implemented and maintained trees on their farmland or in the farmyard. Tree species most commonly established on farmland or in farm yards in our study included *Ficus hartwegii* (Miq.) Miq., *Guazuma ulmifolia* Lam., *Dipteryx panamensis* (Pittier) Rec. & Mell, *Enterolobium cyclocarpum* Jacq. Griseb., *Mangifera indica* L., *Byrsonima crassifolia* (L.) Kunth, *Psidium friedrichsthalianum* (O. Berg) Nied., *Gliricidia sepium* (Jacq.) Walp., and *Acrocomia aculeate* (Jacq.) Lodd. Ex Mart. Agricultural producers found that these trees served multiple functions such as the production of fruit for livestock and human consumption (69%), and the production of leaves for livestock fodder. They also expressed the hardiness of these trees during the dry season and as such did not shed their leaves. Other valuable services these trees provided included fuel wood (100%), shade for pasture grass and livestock, and enhanced nutrient cycling (98%), and soil and water conservation (96%).

Another agroforestry practice commonly implemented by participants in the GEF-Silvopastoral Study and widely used in Costa Rica included the use of live fences. In our study, all (100%) farmers surveyed implemented live fences and in a previous study by Harvey et al. (2005) over 80% of the agricultural producers surveyed in Costa Rica implemented live fences. In our study, the most common use of live fences was to provide an economical enclosure for livestock, and separating pastures from roads, forested areas, and waterways. Our study participants also observed that live fences provided shade for livestock and pasture grasses. In addition, many of the agricultural producers interviewed believed that live fences provided an ecological service by conserving biodiversity in addition to preventing soil erosion and protecting streams when they are used to separate pastureland from waterways. Live fences also provided foliage for cattle fodder. However, in our study, none of the agricultural producers surveyed discussed the use of live fences for this purpose. Similarly, Harvey et al. (2005) noted in their study that only 10% of Costa Rican agricultural producers used live fences for the production of fodder in addition to their use as an enclosure for pasture lands. This suggested that agricultural producers in Costa Rica were not aware of all possible benefits of live fences, but those that participated in the GEF-Silvopastoral Study had a greater knowledge on the diverse utility of live fences. Other studies also revealed that the conversion of farmland previously containing few or no trees into areas dominated by agroforestry decreased the amount of degraded land by 15% over a 3-year period (Zamora-Lopez, 2006). Zamora-Lopez (2006) also found that the poorest agricultural producers were able to reduce pastureland degradation by introducing improved pasture with trees, by adopting fodder banks, and live fences. As such, a diversification in agricultural production systems included the implementation of a significant tree component that may buffer against income risks associated with current and future shifts in climate (Verchot et al., 2007). Kandji et al. (2006) also pointed out that agroforestry systems have the ability to improve the microclimate which in turn improves the adaptive capacity of land owners to climate change. Additionally, Kandji et al. (2006) suggested that the presence of trees in agricultural croplands can provide agricultural

producers with an additional source of income that helps to strengthen their socioeconomic resilience. For example, tree products including fodder, resins, timber, and fruits provide a higher source of income than corps, and can also buffer against crop failure.

#### **4.3 Producer contingency plans and adaptive capacity**

According to the IPCC (2007) introducing a contingency plan to cope with unexpected changes in climate will increase food security and reduce financial losses. Our study showed that 28% of the agricultural producers researched the issue of climate change in detail and

Climate Change Adaptation using Agroforestry Practices: A Case Study from Costa Rica 135

to adapt to climate change may be due to the underlying differences in the perception of climate change. Some of the producers in his study expressed a lack of knowledge about adaptation strategies, rationing of key resources such as water, lack of appropriate seed, lack of market access and insecure property rights. Pagiola et al. (2008) also noted that the initial costs of implementing fodderbanks using *Brachiaria* grass species and the time lag before receiving any benefit from such activity in Costa Rica was a primary determinant of this management practice. Agricultural producers in our study, who thought climate change is not an environmental issue, were encouraged to implement environmental services for financial gain. The incentives offered by the GEF-Silvopastoral Study through a PES system and their increasing knowledge on the value of environmental services allowed them to

Fig. 3. Factors influencing the ability and motivation of agricultural producers to implement agroforestry systems as a climate change adaptation strategy, Esparza, Costa Rica (n=50).

Results from our study showed that the majority of agricultural producers had already implemented specific management practices to help cope with climate change. Our results also suggested that producers implemented specific agroforestry practices under the direction and guidance of CATIE extension personnel, researchers and the Costa Rican Ministry of Agriculture as part of the GEF-Silvopastoral Study. Through this interaction, agricultural producers became aware that the adoption of agroforestry practices also provided an ecological service, and therefore helped them to adapt to current and future climate change, for which they received a financial incentive. Only a small number of agricultural producers had a contingency plan in place which would help them cope with imminent climate change and reduce financial losses while maintaining food security and livelihoods for their families. However, a large proportion of agricultural producers were seeking further information on climate change contingency plans and relied on social networks built through their interaction with the GEF-Silvopastoral Study. A large number of agricultural producers in our study would readily adopt agroforestry practices as part of an incentive program including a PES system and market incentives, and receive further

**5. Conclusions**

understand and benefit financially through implementing these services.

were able to explain what climate change is and how it will affect food security, their livelihood and families. These agricultural producers were able to link changes caused in the Earth's atmosphere to deforestation and industrial processes, and therefore had implemented a climate change contingency plan. These agricultural producers suggested, and were aware of, that those without a climate change contingency plan may face many additional challenges compared to those with a plan. An additional 50% of the agricultural producers in our study were seeking information about climate change contingency plans. This was because of their interaction with the GEF-Silvopastoral Study and the knowledge gained through this interaction. These agricultural producers expected that climate change will force them to make major adjustments to their land management practices in order to ensure food security and livelihoods for their family in the future. Approximately 56% of these agricultural producers relied on CATIE and 34% on the Costa Rican Ministry of Agriculture to obtain information on climate change and strategies for adaptation. The remaining agricultural producers from our study expressed that the different adaptation strategies they had already implemented as a result of their association with the GEF-Silvopastoral Study provided sufficient protection from negative impacts of climate change on their land.

Adger (2001) suggested that the capacity to adapt to climate change may be enhanced through the improvement of social networks that provide information about climate change. Such social networks, comprised of institutions and organizations fluent in issues surrounding climate change, should work in close association with agricultural producers to assist them in developing strategies to enhance their capacity to adapt to climate change (Gallopin, 2006). Our results showed that 84% of the agricultural producers sought assistance from CATIE and the Ministry of Agriculture to increase their capacity to adapt to climate change. Through the GEF-Silvopastoral Study, CATIE has played a key role in enhancing social networks in Esparza by connecting agricultural producers with the Costa Rican Ministry of Agriculture. A network specifically established for the agricultural producers in this region provided opportunities to connect with each other to learn about new climate change adaptation strategies through the implementation of agroforestry practices.

Nhemachena & Hassan (2007) observed that widespread information on climate change to agricultural producers enhanced their capacity to adapt to climate change, and led to the development and implementation of long-term contingency plans. Füssel (2007) also found that if agricultural producers understood the inherent changes expected as a result of climate change, then they improved their ability to adapt and decreased their overall cost of adaptation. Agricultural producers decided which land management practices to implement based on profit, grain yield and/or livestock productivity (Adger, 2001). Approximately 70% of agricultural producers in our study stated that market incentives either through credits or PES will increase their capacity to adapt to climate change. Based on the qualitative discussions with agricultural producers and the quantitative data collected in the surveys, several factors influenced their capacity and motivation to implement adaptation strategies (Figure 3). Our results showed that the producer's ability and motivation to implement climate change adaptation strategies was strongly influenced by financial incentives through a PES system which would also cover costs of tree planting and other expenses related to the adoption of agroforestry practices. Increased market incentives (e.g. eco-labelling) or other incentives to increase the marketability of their products, and nonfinancial assistance to help increase their capacity to adapt to climate change were requested by those surveyed in our study. Maddison (2007) pointed out that differences in the capacity to adapt to climate change may be due to the underlying differences in the perception of climate change. Some of the producers in his study expressed a lack of knowledge about adaptation strategies, rationing of key resources such as water, lack of appropriate seed, lack of market access and insecure property rights. Pagiola et al. (2008) also noted that the initial costs of implementing fodderbanks using *Brachiaria* grass species and the time lag before receiving any benefit from such activity in Costa Rica was a primary determinant of this management practice. Agricultural producers in our study, who thought climate change is not an environmental issue, were encouraged to implement environmental services for financial gain. The incentives offered by the GEF-Silvopastoral Study through a PES system and their increasing knowledge on the value of environmental services allowed them to understand and benefit financially through implementing these services.

Fig. 3. Factors influencing the ability and motivation of agricultural producers to implement agroforestry systems as a climate change adaptation strategy, Esparza, Costa Rica (n=50).

#### **5. Conclusions**

Global Warming Impacts – Case Studies on

134 the Economy, Human Health, and on Urban and Natural Environments

were able to explain what climate change is and how it will affect food security, their livelihood and families. These agricultural producers were able to link changes caused in the Earth's atmosphere to deforestation and industrial processes, and therefore had implemented a climate change contingency plan. These agricultural producers suggested, and were aware of, that those without a climate change contingency plan may face many additional challenges compared to those with a plan. An additional 50% of the agricultural producers in our study were seeking information about climate change contingency plans. This was because of their interaction with the GEF-Silvopastoral Study and the knowledge gained through this interaction. These agricultural producers expected that climate change will force them to make major adjustments to their land management practices in order to ensure food security and livelihoods for their family in the future. Approximately 56% of these agricultural producers relied on CATIE and 34% on the Costa Rican Ministry of Agriculture to obtain information on climate change and strategies for adaptation. The remaining agricultural producers from our study expressed that the different adaptation strategies they had already implemented as a result of their association with the GEF-Silvopastoral Study provided sufficient protection from negative impacts of climate change

Adger (2001) suggested that the capacity to adapt to climate change may be enhanced through the improvement of social networks that provide information about climate change. Such social networks, comprised of institutions and organizations fluent in issues surrounding climate change, should work in close association with agricultural producers to assist them in developing strategies to enhance their capacity to adapt to climate change (Gallopin, 2006). Our results showed that 84% of the agricultural producers sought assistance from CATIE and the Ministry of Agriculture to increase their capacity to adapt to climate change. Through the GEF-Silvopastoral Study, CATIE has played a key role in enhancing social networks in Esparza by connecting agricultural producers with the Costa Rican Ministry of Agriculture. A network specifically established for the agricultural producers in this region provided opportunities to connect with each other to learn about new climate change adaptation strategies through the implementation of agroforestry

Nhemachena & Hassan (2007) observed that widespread information on climate change to agricultural producers enhanced their capacity to adapt to climate change, and led to the development and implementation of long-term contingency plans. Füssel (2007) also found that if agricultural producers understood the inherent changes expected as a result of climate change, then they improved their ability to adapt and decreased their overall cost of adaptation. Agricultural producers decided which land management practices to implement based on profit, grain yield and/or livestock productivity (Adger, 2001). Approximately 70% of agricultural producers in our study stated that market incentives either through credits or PES will increase their capacity to adapt to climate change. Based on the qualitative discussions with agricultural producers and the quantitative data collected in the surveys, several factors influenced their capacity and motivation to implement adaptation strategies (Figure 3). Our results showed that the producer's ability and motivation to implement climate change adaptation strategies was strongly influenced by financial incentives through a PES system which would also cover costs of tree planting and other expenses related to the adoption of agroforestry practices. Increased market incentives (e.g. eco-labelling) or other incentives to increase the marketability of their products, and nonfinancial assistance to help increase their capacity to adapt to climate change were requested by those surveyed in our study. Maddison (2007) pointed out that differences in the capacity

on their land.

practices.

Results from our study showed that the majority of agricultural producers had already implemented specific management practices to help cope with climate change. Our results also suggested that producers implemented specific agroforestry practices under the direction and guidance of CATIE extension personnel, researchers and the Costa Rican Ministry of Agriculture as part of the GEF-Silvopastoral Study. Through this interaction, agricultural producers became aware that the adoption of agroforestry practices also provided an ecological service, and therefore helped them to adapt to current and future climate change, for which they received a financial incentive. Only a small number of agricultural producers had a contingency plan in place which would help them cope with imminent climate change and reduce financial losses while maintaining food security and livelihoods for their families. However, a large proportion of agricultural producers were seeking further information on climate change contingency plans and relied on social networks built through their interaction with the GEF-Silvopastoral Study. A large number of agricultural producers in our study would readily adopt agroforestry practices as part of an incentive program including a PES system and market incentives, and receive further

Climate Change Adaptation using Agroforestry Practices: A Case Study from Costa Rica 137

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#### **6. Acknowledgements**

Financial support was provided by Inter-American Institute for Co-operation in Agriculture, Canada, the Global Environment Facility Silvopastoral Study, and the University of Waterloo. We also thank Dr. M.A. Ibrahim and C. Cepulveda for assistance with research logistics and access to the GEF-Silvopastoral Study data base. We thank Francisco Casasola, and the Costa Rican Ministry of Agriculture for assistance in the field.

#### **7. References**

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**6. Acknowledgements**

1099-1328.

**7. References**

**9**

*Japan*

**Crop Production and Global Warming**

*1Graduate school of Horticulture, Chiba University*

Masahumi Johkan1, Masayuki Oda2, Toru Maruo1 and Yutaka Shinohara1

Crop production will be affected by global warming, resulting in world-wide food shortages and starvation. Increased concentrations of carbon dioxide (CO2), one of the main substances responsible for global warming, will promote plant growth through intensified photosynthesis. Some reports indicate that a rise in the levels of CO2 would actually benefit plants, rather than harm them. The growth rates of C3 plants increase in response to elevated concentrations of carbon dioxide. Thus, global warming might increase plant

High atmospheric temperatures caused by elevated concentrations of CO2 will induce heat injury and physiological disorders in some crops, which will decrease the incomes of farmers and agricultural countries. Photosynthesis is one of the most sensitive physiological processes to high temperature stress. Reproductive development is more sensitive than vegetative development to high temperatures, and heat-sensitivity differs among crops. In tomato, the optimal temperature for fruit set was reported as 21–24°C (Geisenberg and Stewart, 1986) or 22–25°C (Peet and Bartholomew, 1996), while pollen viability and release are adversely affected by high temperatures, and become major limiting factors for fruit set. Thus, global warming can have opposite effects on plant growth. From a long-term viewpoint, however, high atmospheric temperatures will drive the main sites of crop

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Global warming is thought to be related to strong hurricanes, cyclones, and typhoons. These extreme weather events can seriously damage crop production, and destabilize farm management and the lives of consumers. However, these agricultural problems are most

In this chapter, we summarize some of the agricultural problems and crop damage that result from global warming, and present some technical countermeasures (not political and administrative countermeasures) that could be used to ameliorate the effects of global

**1. Introduction**

over irrigation water and food.

likely to occur in the medium and long-term future.

*2Graduate school of Life Science and Environment, Osaka Prefecture University*

### **Crop Production and Global Warming**

Masahumi Johkan1, Masayuki Oda2, Toru Maruo1 and Yutaka Shinohara1 *1Graduate school of Horticulture, Chiba University 2Graduate school of Life Science and Environment, Osaka Prefecture University Japan*

#### **1. Introduction**

Global Warming Impacts – Case Studies on

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production at dual-purpose cattle farms at the semi-humid old agricultural frontier

composición, conectividad y el stock de carbono presente en el paisaje ganadero de Esparza, Costa Rica. M.Sc. Thesis Centro Agronómico Tropical de Investicación y Crop production will be affected by global warming, resulting in world-wide food shortages and starvation. Increased concentrations of carbon dioxide (CO2), one of the main substances responsible for global warming, will promote plant growth through intensified photosynthesis. Some reports indicate that a rise in the levels of CO2 would actually benefit plants, rather than harm them. The growth rates of C3 plants increase in response to elevated concentrations of carbon dioxide. Thus, global warming might increase plant growth, because of higher temperatures and higher levels of atmospheric CO2.

High atmospheric temperatures caused by elevated concentrations of CO2 will induce heat injury and physiological disorders in some crops, which will decrease the incomes of farmers and agricultural countries. Photosynthesis is one of the most sensitive physiological processes to high temperature stress. Reproductive development is more sensitive than vegetative development to high temperatures, and heat-sensitivity differs among crops. In tomato, the optimal temperature for fruit set was reported as 21–24°C (Geisenberg and Stewart, 1986) or 22–25°C (Peet and Bartholomew, 1996), while pollen viability and release are adversely affected by high temperatures, and become major limiting factors for fruit set. Thus, global warming can have opposite effects on plant growth. From a long-term viewpoint, however, high atmospheric temperatures will drive the main sites of crop production further north, establishing new rules for the 'right crop for right land'.

Water shortages caused by global warming will be the greatest problem for crop production. Plants fundamentally rely on adequate fresh water, and agricultural water accounts for 70% of water use world-wide. As higher temperatures increase evaporation from water sources and decrease precipitation, arid regions will become further desertified. Particularly in semiarid regions, the cultivatable area will decrease because of drought, and this could result in famines and mass migration. As well, it is likely that there will be human conflicts over irrigation water and food.

Global warming is thought to be related to strong hurricanes, cyclones, and typhoons. These extreme weather events can seriously damage crop production, and destabilize farm management and the lives of consumers. However, these agricultural problems are most likely to occur in the medium and long-term future.

In this chapter, we summarize some of the agricultural problems and crop damage that result from global warming, and present some technical countermeasures (not political and administrative countermeasures) that could be used to ameliorate the effects of global

Crop Production and Global Warming 141

In plants, the promotion of photosynthesis under high CO2 concentrations results in increased dry matter production. This is known as the "CO2 fertilizer effect", and it is used to promote crop growth in greenhouses and plant factories. This effect is more pronounced in C3 crops, such as wheat, soybean, and rice, but less so in C4 crops, such as maize, millet, and sugarcane. This is because the current atmospheric CO2 concentration limits photosynthesis in C3 plants, but not in C4 plants because of their ability to concentrate CO2 in the cells (Fig. 2). If the concentration of CO2 is doubled, the photosynthetic rate of many C3 plants increases by 30–60%, but in most C3 plants these promoted rates are temporary, and there are no promotion effects in the long term. Thus, it is thought that the changes in the photosynthetic apparatus or other photosynthetic factors that occur during short-term responses to increased CO2 differ from those during long-term exposure to increased CO2. This phenomenon often occurs when photosynthetic production exceeds plant growth

C4 plants

0 200 400<PHONE_NUMBER>

C3 plants

CO2 (ppm)

The effects of CO2 concentration on crop yield will become greater as the atmospheric CO2 concentration increases. For many crops, the predicted yield increase in response to a 700 ppm CO2 concentration is approximately 30%; specifically, a yield increase of 31% in wheat (Amthor, 2001), 29–35% in rice (Cock and Yoshida, 1973; Imai et al., 1985) 55% in soybean (Rogers et al., 1983), and 50% in maize (Rogers et al., 1983). However, the promoting effects will vary according to the specific nature of the plant and its sinks, e.g., seeds or bulbs. Even though photosynthesis in C3-type crops is generally inhibited by long-term exposure to high CO2 concentrations, those that have separate organs to accumulate photosynthetic products appear to be unaffected. For example, inhibition of photosynthesis in crops such as radish and potatoes has not been observed (Sage et al., 1989; Usuda and Simogawara, 1998). Also, if water and mineral nutrients become limiting factors, the promoting effects of increased CO2

Fig. 2. Photosynthetic curves for C3 and C4 plants (Rogers &Runion, 1994).

(Nakano et al., 1997; Makino, 1994).

0

20

Photosynthesis (

μmol m-2 s-1)

40

60

warming on crop production. We also discuss parthenocarpy and grafting as potential countermeasures.

#### **2. Effects of global warming on plant growth**

#### **2.1 Carbon dioxide**