**2.1. Experience of landscape with ecology**

for adjacent upland development, and provide multiple services such as protection of water quality, and flood and erosion control. Furthermore, coastal wetlands provide visual diversity and unique visual character, which significantly influences the well-being of people and their emotional attachment to the environment. For various reasons, half of the world's wetlands have disappeared since 1990, and therefore, wetlands have become the most threatened landscape type. Anthropogenic activities can impact the coastal wetland environment in different ways. Furthermore, coastal marshes and swamps are vulnerable to climate change and sea

Land use, economic development demands, reclamation of land from the sea, and natural oceanographic processes can alter the coastal wetland environment. To manage these anthropogenic and natural factors, man-made structures have been applied to protect and maintain the intertidal zone. Man-made structures can affect the coastal wetland ecology by reducing coastal area, disrupting natural water flow, and threatening species survival. Furthermore, such structures hinder people close to water, change the visual perception of the landscape, decrease the esthetic value, and weaken the environmental attachment for local people.

Although support for wetland conservation is strong, wetlands are disappearing. Urban sprawl and increase in population density are primarily attributable for wetland loss. Environmental education, besides policies and legislations, is a commonly adopted strategy to encourage public participation in wetland protection activities. Widespread wetland degradation and loss may imply a generational knowledge gap about environmental issues.

Due to land development activities, man-made structures are playing an increasingly dominant role in shaping the coastal wetland environment [1]. People were surrounded by the scenery in their daily life. Both older and younger generations are affected by modified coastal wetlands environments frequently. An understanding of the healthy ecological conditions in the past is lacking, and therefore, environmental norms continue to change. Loss of an ecological baseline will bring about still unknown challenges for coastal wetland

It was widely hypothesized that landscape esthetic is a stimulus–response relationship based on the interaction between humans and the environment. The human perception of the environment is immediate and is accompanied by short-term emotional pleasure, while ecological esthetic is a knowledge-based cognitive experience where long-lasting pleasure is obtained through understanding. It is debated whether people can directly sense ecological quality; however, based on evolutionary and cultural theory, good landscape esthetics is associated with high ecological quality. For survival, people choose suitable habitats and alter them to suit their needs, while there is a sense of enjoyment and desire to live among scenery perceived as beautiful. There are common physical environmental elements, which affect landscape, ecological function, and the composition of visual image, individually. For example, ecological functions affect the appearance of a landscape and people appreciate the appearance; therefore, good ecological health would be inherently included in the landscape

Ecologists have worked toward improving the public's environmental protection awareness through environmental education. The willingness to protect a habitat will triple if the

level rise.

134 Wetlands Management - Assessing Risk and Sustainable Solutions

conservation [2, 3].

esthetic.

Landscape esthetic is based on the idea that human preference for a particular physical landscape is rooted in biological or evolutionary adaption [7–9]. The habitat theory and the information-processing theory provide insight into why people may prefer certain landscape characteristics. These theories suggest that human interactions with the environment are related to various survival behaviors. An environment benefited to people that provided those with the capacity to observe without being seen meant both prospect- and refugedominant landscape settings were more preferred.

Humans require environmental information to understand their surroundings. According to the information processing theory [9, 10], human perception is oriented to understand and react to the environment. High coherence setting means that the setting is orderly, and legibility can be more preferred. An environmental setting with high species richness and diversity indicates complexity. The human environmental perception of this situation could be mysteriousness in which humans react by exploring their surroundings and discover valuable resources. Conversely, highly homogenous or too heterogeneous environmental setting could induce an uninterested or fearful environmental perception, provoking a reaction to escape. The human perception of environmental settings and information provides critical guidance for determining which habitats are suitable.

When people interact with environment, they have an esthetic experience and emotional response. Together, these reactions influence the choice of the landscape. Spatial and temporal changes of landscape can result from ecological functions. These landscape changes, stemming from various ecological functions, will influence the esthetic perception of a landscape through time.

Positive responses to characteristics of a setting generally increase chances of survival or wellbeing. On the other hand, esthetic is also shaped by cultural expectations [11–13] and contemporary environmental behaviors [13]. Esthetic experiences drive landscape change in the context of habitat, leisure, recreation activities, and daily life. For example, in an esthetically pleasing environment, people are more prone to enjoy, have a connection with, and protect it. In an esthetically unpleasing, ugly, or unsafe environment, people would avoid it or seek to improve it (**Figure 1**). Environment in which improvements are usually made tends to be those which people enjoy or are preferable for land use. The resulting changes may or may not benefit landscape esthetic and ecology. The esthetic experience provides a good linkage between the human benefits of landscapes and healthy ecological functions, which is based on the evolutionary theory that a healthy ecological setting is associated with landscape characteristics that are esthetically preferable.

The perceptual cues stemming from the interaction between humans and environment can be used to assess which settings evoke particular reactions (**Figure 2**). Both evolutionary and cultural drivers suggest that ecological health is associated with a pleasing esthetic landscape.

> In this way, humans can sense environmental information, landscape esthetic, and ecological health. The arrangement of the physical characteristics of landscape significantly affects the perception of the landscape esthetic and thus ecological function. Environmental information culminates in four attributes to derive landscape preference. A coherent and orderly setting is easy to understand and as such enables people to feel legibility and secure; conversely, a complex setting made people fell mystery would encourage curiosity and stimulate exploration. A more detailed description of preferable landscape characteristics is shown in Kaplans' environmental preference matrix [9, 10, 14]. Ecologically, these characteristics correspond to species diversity, richness, evenness, and abundance, which taken together, constitute landscape ecology. Further aspects of landscape ecology include patch heterogeneity, disturbance, size, and edge structure and habitat naturalness and continuity [10]. Humans ascertain environmental information from the diversity and evenness of a patch, this setting is favorable as it is representative coherence and legibility and thus security. Natural landscapes are favored by human; the continuity of patches implies that plenty of environmental information is avail-

> **Figure 2.** Landscape versus ecological experience. Landscape and ecology have common physical environmental elements, which include scenery and structure of landscape ecology. Four cognitive attributes of environmental information influence people's landscape esthetic preference. There are four ecological indicators of ecological health.

Combining the Aesthetic and Ecological Aspects of Man-Made Structures on Coastal Wetlands

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137

able in the middle to background, which could induce curiosity and exploration [15].

ficial wetlands, divided into the four quadrants in **Figure 3**.

Humans are closely linked to the wetland environment and as such, human activity has altered the wetland landscape and ecological function. A wetland model of landscape esthetics versus ecological processes was created (**Figure 3**). At the opposite ends of the ecological processes, axes are ecological services and human activities, while on the landscape esthetics, axes are natural beauty and formal beauty. There were four principal types of wetlands included: (1) natural wetlands, (2) modified wetlands, (3) recreational wetlands, and (4) arti-

**Figure 1.** The process of landscape experience and resulting landscape change. The esthetic component was affected by the interaction between human and landscape. Therefore, landscape change may benefit both landscape and ecology (ecological esthetics). Otherwise, the existing situation will lead to generational knowledge gaps and shift the baselines of landscape and ecology. Therefore, integrating esthetic and ecological design approaches to improve unfriendly landscape and ecology coastal wetland is important.

Combining the Aesthetic and Ecological Aspects of Man-Made Structures on Coastal Wetlands http://dx.doi.org/10.5772/intechopen.79572 137

When people interact with environment, they have an esthetic experience and emotional response. Together, these reactions influence the choice of the landscape. Spatial and temporal changes of landscape can result from ecological functions. These landscape changes, stemming from various ecological functions, will influence the esthetic perception of a landscape

Positive responses to characteristics of a setting generally increase chances of survival or wellbeing. On the other hand, esthetic is also shaped by cultural expectations [11–13] and contemporary environmental behaviors [13]. Esthetic experiences drive landscape change in the context of habitat, leisure, recreation activities, and daily life. For example, in an esthetically pleasing environment, people are more prone to enjoy, have a connection with, and protect it. In an esthetically unpleasing, ugly, or unsafe environment, people would avoid it or seek to improve it (**Figure 1**). Environment in which improvements are usually made tends to be those which people enjoy or are preferable for land use. The resulting changes may or may not benefit landscape esthetic and ecology. The esthetic experience provides a good linkage between the human benefits of landscapes and healthy ecological functions, which is based on the evolutionary theory that a healthy ecological setting is associated with landscape char-

The perceptual cues stemming from the interaction between humans and environment can be used to assess which settings evoke particular reactions (**Figure 2**). Both evolutionary and cultural drivers suggest that ecological health is associated with a pleasing esthetic landscape.

**Figure 1.** The process of landscape experience and resulting landscape change. The esthetic component was affected by the interaction between human and landscape. Therefore, landscape change may benefit both landscape and ecology (ecological esthetics). Otherwise, the existing situation will lead to generational knowledge gaps and shift the baselines of landscape and ecology. Therefore, integrating esthetic and ecological design approaches to improve unfriendly

through time.

acteristics that are esthetically preferable.

136 Wetlands Management - Assessing Risk and Sustainable Solutions

landscape and ecology coastal wetland is important.

**Figure 2.** Landscape versus ecological experience. Landscape and ecology have common physical environmental elements, which include scenery and structure of landscape ecology. Four cognitive attributes of environmental information influence people's landscape esthetic preference. There are four ecological indicators of ecological health.

In this way, humans can sense environmental information, landscape esthetic, and ecological health. The arrangement of the physical characteristics of landscape significantly affects the perception of the landscape esthetic and thus ecological function. Environmental information culminates in four attributes to derive landscape preference. A coherent and orderly setting is easy to understand and as such enables people to feel legibility and secure; conversely, a complex setting made people fell mystery would encourage curiosity and stimulate exploration. A more detailed description of preferable landscape characteristics is shown in Kaplans' environmental preference matrix [9, 10, 14]. Ecologically, these characteristics correspond to species diversity, richness, evenness, and abundance, which taken together, constitute landscape ecology. Further aspects of landscape ecology include patch heterogeneity, disturbance, size, and edge structure and habitat naturalness and continuity [10]. Humans ascertain environmental information from the diversity and evenness of a patch, this setting is favorable as it is representative coherence and legibility and thus security. Natural landscapes are favored by human; the continuity of patches implies that plenty of environmental information is available in the middle to background, which could induce curiosity and exploration [15].

Humans are closely linked to the wetland environment and as such, human activity has altered the wetland landscape and ecological function. A wetland model of landscape esthetics versus ecological processes was created (**Figure 3**). At the opposite ends of the ecological processes, axes are ecological services and human activities, while on the landscape esthetics, axes are natural beauty and formal beauty. There were four principal types of wetlands included: (1) natural wetlands, (2) modified wetlands, (3) recreational wetlands, and (4) artificial wetlands, divided into the four quadrants in **Figure 3**.

**Figure 3.** A matrix of the four types of wetlands in terms of landscape esthetics and ecological processes.

The natural wetland quadrant is united by ecological services and natural beauty. This indicates that natural interference of ecological process affected the ecological health of the wetland, and the natural process is the dominant pattern. Here, is more stability with fewer disturbances, and to affect ecosystem health coupled with landscape naturalness to deliver a high esthetic value.

this scenario, ecological health and landscape esthetic are mutually reinforcing each other. Designs can be introduced to achieve a particular ecological esthetic preference. The impacts of human activities will be minimized by eco-oriented approaches, as these approaches can regenerate damaged wetlands and particularly aim to improve the ecological functioning and

**Figure 4.** The three-dimensional model consisted of ecological processes, landscape esthetics and design approaches.

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Design orientation can lead to sustainable or unsustainable wetland development.

 The engineering-oriented design puts human activity at the forefront within these settings. Deterioration of ecological services and functions are foreseeable. The characters of engineering-oriented approaches are degenerated that may show the tendency of unsustainable

Increasing population and urban sprawl led to reclamation of natural wetlands, habitat loss, and shifting of wetland types in the affected areas. Thus, the ecological baseline has shifted, increasing the difficulty of wetland conservation. Throughout the history of land protection, esthetic factors are given great importance [16]. That means human esthetic preference and ecological goals are aligned. Therefore, improved esthetics is a key component for ecological restoration of

Coastal wetlands are areas where different habitat overlap, such as sea and land, river and estuary, and brackish water and freshwater. Vegetation and animals from both adjoining

maximize the naturalness of beauty.

**2.2. Impact of man-made structures on coastal wetland**

wetland development.

threatened wetlands.

 Artificial wetlands are related to in varying degrees of anthropogenic utilization, distributed from the center city to urban the fringe. Contrary to natural wetlands, human interventions, such as design-orientation, engineering, and maintained works, are practiced in here. Human activities highly limited ecological processes and functions but increase formal beauty.

Ecological services form modified wetlands, which are esthetically pleasing. These wetlands were modified to protect coastal from erosion or to meet land use demands. Ecological services decline as the number of man-made structures increases. Finally, recreational wetlands facilitate human activities and natural beauty. In recreational wetlands, recreational intensity directly disturbed to ecological quality, together with the naturalness of beauty.

In addition to the described two-dimensional framework, a Z-axis depicting design approaches is overlaid to form a three-dimensional model. The two ends of design approach are eco-oriented and engineering-oriented and would promote either natural beauty or formal beauty. This will impact the landscape esthetics, which, as previously described, influences ecological processes (**Figure 4**).

Natural beauty corresponds to an ecologically esthetic landscape, where the appearance of ecological function is visible, emphasizing the visual enjoyment of natural scenery. In Combining the Aesthetic and Ecological Aspects of Man-Made Structures on Coastal Wetlands http://dx.doi.org/10.5772/intechopen.79572 139

**Figure 4.** The three-dimensional model consisted of ecological processes, landscape esthetics and design approaches. Design orientation can lead to sustainable or unsustainable wetland development.

this scenario, ecological health and landscape esthetic are mutually reinforcing each other. Designs can be introduced to achieve a particular ecological esthetic preference. The impacts of human activities will be minimized by eco-oriented approaches, as these approaches can regenerate damaged wetlands and particularly aim to improve the ecological functioning and maximize the naturalness of beauty.

 The engineering-oriented design puts human activity at the forefront within these settings. Deterioration of ecological services and functions are foreseeable. The characters of engineering-oriented approaches are degenerated that may show the tendency of unsustainable wetland development.

Increasing population and urban sprawl led to reclamation of natural wetlands, habitat loss, and shifting of wetland types in the affected areas. Thus, the ecological baseline has shifted, increasing the difficulty of wetland conservation. Throughout the history of land protection, esthetic factors are given great importance [16]. That means human esthetic preference and ecological goals are aligned. Therefore, improved esthetics is a key component for ecological restoration of threatened wetlands.

### **2.2. Impact of man-made structures on coastal wetland**

The natural wetland quadrant is united by ecological services and natural beauty. This indicates that natural interference of ecological process affected the ecological health of the wetland, and the natural process is the dominant pattern. Here, is more stability with fewer disturbances, and to affect ecosystem health coupled with landscape naturalness to deliver a high esthetic value.  Artificial wetlands are related to in varying degrees of anthropogenic utilization, distributed from the center city to urban the fringe. Contrary to natural wetlands, human interventions, such as design-orientation, engineering, and maintained works, are practiced in here. Human activi-

Ecological services form modified wetlands, which are esthetically pleasing. These wetlands were modified to protect coastal from erosion or to meet land use demands. Ecological services decline as the number of man-made structures increases. Finally, recreational wetlands facilitate human activities and natural beauty. In recreational wetlands, recreational intensity

In addition to the described two-dimensional framework, a Z-axis depicting design approaches is overlaid to form a three-dimensional model. The two ends of design approach are eco-oriented and engineering-oriented and would promote either natural beauty or formal beauty. This will impact the landscape esthetics, which, as previously described, influences ecological processes

Natural beauty corresponds to an ecologically esthetic landscape, where the appearance of ecological function is visible, emphasizing the visual enjoyment of natural scenery. In

ties highly limited ecological processes and functions but increase formal beauty.

**Figure 3.** A matrix of the four types of wetlands in terms of landscape esthetics and ecological processes.

138 Wetlands Management - Assessing Risk and Sustainable Solutions

directly disturbed to ecological quality, together with the naturalness of beauty.

(**Figure 4**).

Coastal wetlands are areas where different habitat overlap, such as sea and land, river and estuary, and brackish water and freshwater. Vegetation and animals from both adjoining ecosystems overlap here, resulting in ecotones which are species rich and diverse. Increasing modification of coastal wetlands is a symptom of increasing urbanization and contemporary behaviors.

The coast offers an open ecological environment, rich in scenic beauty that provides enjoyment and contributes to the well-being of people who experience it. Populations in coastal areas are increasing, and the resulting urbanization intensifies the conflict between anthropogenic activities and the coastline. Man-made structures (e.g., seawalls and breakwaters) protect the coastal environment from the impacts of waves, tides, and storms. These structures affect the natural ecosystem and ecotones [1], undermine the coastal scenic value, and obstruct the human access to coastline.

Certain physical attributes of coastal wetlands have influenced on both the landscape esthetic and ecological health including the water body, water shore, and terrestrial vegetation. Each of these attributes constitute to the overall coastal wetland landscape. Environmental perception is derived from the environment, which physically surrounds people [17–19]. Therefore, if manmade structures were constructed, the shoreline is altered and access to the physical environment could be prohibited; this is the primary issue of man-made structures in coastal wetlands.

Characteristics of man-made structures, such as length, shape, height, slope, material, type, and location, influence the perception of the coastal wetland. The length of structures would reduce the attractiveness of the coastal landscape [20] and also decrease landscape room. Landscape room is a perceptual unit related to a visual scale. It takes into consideration the ecological patch size. The view and size of landscape room determines the degree of openness, which affects visual pleasure. Man-made structures fragment coastal wetlands and can limit the exchange of seawater with freshwater, resulting in ecotone loss.

Man-made structures can increase edge abruptness and inflict straight boundaries, both edge effects tend to decrease species movement across an edge. These structures are generally straight, hard edged, and simple and have produced monotonous and visually uninteresting coastal wetlands. The less variety of landscape elements produces a setting that fails to induce curiosity, indicated are unlikely to explore for more environmental information. Furthermore, a completely blocked view or landscaping barrier fails to go deeper to get more environmental information and thus is not favorable landscape. The height of typical man-made structures obstructs visual penetration and esthetic value [21] and reduces species movement, eco-hydrological function, and energy flows [1, 22].

Finally, the material in which man-made structures are made from is associated with a lower probability of species colonization. The shape and material of the structure are two key factors that will influence their performance as ecosystem services providers [23]. **Table 1** details the

Many approaches have been applied to mitigate the ecological impacts of man-made structures on coastal wetlands as reported by Wiecek [24]. These mitigation efforts also need to incorporate a landscape approach to improve esthetic value [25]. Landscape esthetic preference stems from the evolutionary survival experience. In this way, landscape esthetic is aligned with

impacts of man-made structures on the landscape and ecology of coastal wetlands.

**Table 1.** The impacts of man-made structures on landscape esthetics and the ecology of coastal wetlands.

**3. Esthetic and ecology aspects of man-made structures**

**Landscape esthetic impacts Characteristics of**

Diminished scale of the landscape room and reduced environmental information. Altered skyline to monotonous spatial

Visual landscape diversity weakened, decreased availability of environmental

Obstruction of visual penetration. Reduction in the openness of the spatial landscape. The closed setting reduces available environmental information.

with increasing slope.

and visual variety.

the setting.

landscape room.

Water and coastline accessibility decreases

Structures type can influence accessibility

Improper structure location will affect the holistic coastal wetland, thus the size of

For example, structures upon which vegetation can grow increases the amenity of

Unvaried surfaces make the spatial landscape is too tidy, uninteresting and unliving, reduction in the amount of environmental information available.

landscape.

information.

**man-made structures**

**Ecological function impacts**

increased probability of species loss.

Habitat fragmentation could reduce population size, habitat diversity, and species diversity.

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141

boundaries straight, hard, and homogeneous. The edge effect influenced the flow of nutrients, water, energy, and species

structures serve as barriers that divide sea and land, and restrict species movement and

the available inter-tidal habitat on seawalls, which could reduce species richness and

natural ecotone and does not support species

daily or less frequent tidal inundation which could affect vegetation and decrease or

redistribution. The sea and land both could be

damaged from segmented habitats.

Length Reduced area and quality of coastal wetland,

Shape Man-made structures made the patch

Combining the Aesthetic and Ecological Aspects of Man-Made Structures on Coastal Wetlands

movement.

abundance.

Height Ecotones vanished because man-made

energy and water flows.

Slope The near-vertical slope of structures reduces

Material The substrate is different between levee and

Type Different types of levee may receive either

Location The location of a structure affects habitats

endemic to coastal wetlands.

fragment coastal wetlands.

The different types of man-made structures are discrepancy in location, width, height, and slope, etc. Coastal ecotones have vanished due to the wide, tall, and steep design of manmade structures [23], which limited "accessibility." Limited accessibility has several implications which can affect perception and include the distance a person can stand from seawater, decreased visual penetration, and a decrease in obtainable environmental information. More important, species movements of both adjacent land and sea were interrupted. Each of these implications could reduce the likelihood of individuals to connect with and pursue conservation action of the coastal wetland environment. Environmental information is not readily available in the current setting; water and land are separated and the coastal wetland has lost its landscape ecology characters.

ecosystems overlap here, resulting in ecotones which are species rich and diverse. Increasing modification of coastal wetlands is a symptom of increasing urbanization and contemporary

The coast offers an open ecological environment, rich in scenic beauty that provides enjoyment and contributes to the well-being of people who experience it. Populations in coastal areas are increasing, and the resulting urbanization intensifies the conflict between anthropogenic activities and the coastline. Man-made structures (e.g., seawalls and breakwaters) protect the coastal environment from the impacts of waves, tides, and storms. These structures affect the natural ecosystem and ecotones [1], undermine the coastal scenic value, and

Certain physical attributes of coastal wetlands have influenced on both the landscape esthetic and ecological health including the water body, water shore, and terrestrial vegetation. Each of these attributes constitute to the overall coastal wetland landscape. Environmental perception is derived from the environment, which physically surrounds people [17–19]. Therefore, if manmade structures were constructed, the shoreline is altered and access to the physical environment could be prohibited; this is the primary issue of man-made structures in coastal wetlands. Characteristics of man-made structures, such as length, shape, height, slope, material, type, and location, influence the perception of the coastal wetland. The length of structures would reduce the attractiveness of the coastal landscape [20] and also decrease landscape room. Landscape room is a perceptual unit related to a visual scale. It takes into consideration the ecological patch size. The view and size of landscape room determines the degree of openness, which affects visual pleasure. Man-made structures fragment coastal wetlands and can

Man-made structures can increase edge abruptness and inflict straight boundaries, both edge effects tend to decrease species movement across an edge. These structures are generally straight, hard edged, and simple and have produced monotonous and visually uninteresting coastal wetlands. The less variety of landscape elements produces a setting that fails to induce curiosity, indicated are unlikely to explore for more environmental information. Furthermore, a completely blocked view or landscaping barrier fails to go deeper to get more environmental information and thus is not favorable landscape. The height of typical man-made structures obstructs visual penetration and esthetic value [21] and reduces species

The different types of man-made structures are discrepancy in location, width, height, and slope, etc. Coastal ecotones have vanished due to the wide, tall, and steep design of manmade structures [23], which limited "accessibility." Limited accessibility has several implications which can affect perception and include the distance a person can stand from seawater, decreased visual penetration, and a decrease in obtainable environmental information. More important, species movements of both adjacent land and sea were interrupted. Each of these implications could reduce the likelihood of individuals to connect with and pursue conservation action of the coastal wetland environment. Environmental information is not readily available in the current setting; water and land are separated and the coastal wetland has lost

limit the exchange of seawater with freshwater, resulting in ecotone loss.

movement, eco-hydrological function, and energy flows [1, 22].

its landscape ecology characters.

behaviors.

obstruct the human access to coastline.

140 Wetlands Management - Assessing Risk and Sustainable Solutions

**Table 1.** The impacts of man-made structures on landscape esthetics and the ecology of coastal wetlands.

Finally, the material in which man-made structures are made from is associated with a lower probability of species colonization. The shape and material of the structure are two key factors that will influence their performance as ecosystem services providers [23]. **Table 1** details the impacts of man-made structures on the landscape and ecology of coastal wetlands.


**8. Prevention and future considerations**

After analyzing the literature of IE in different regions of the world, we found different pathogens depending on the endemic regions for some pathologies, for example, RHD, usage of antibiotic treatment before having a diagnosis, endemic zones for rare pathogens such as *Brucella* spp. in Turkey or even zoonosis reported by Watt et al. [7, 16, 20].

One of the recommendations for developing countries must be an adequate treatment and follow-up for group A beta-hemolytic streptococcus to prevent rheumatic fever and its cardiac complications, which is one of the most common causes of IE in general population and in HD 19 patients in developing countries [16].

There are many different scenarios between developed and developing countries, but we think that the security measures for prevention of bacteremia in HD can be achieved in any health care unit using HD program regardless of the place. Reducing bacteremia in HD patients will reduce their incidence of IE [16].

Pronovost et al. in their study made in 103 UCIs in Michigan used basic changes in their practice of catheter implantation and management. An evidence-based intervention resulted in a large and sustained reduction (up to 66%) in rates of catheter-related bloodstream infection that was maintained throughout the 18-month study period [29].


**4. Conclusion**

The effect of crude oil on the mechanical properties of sand and its concrete were reviewed to evaluate their suitability for engineering applications and the following conclusions can be drawn:

and concrete using fine sand contaminated with higher crude oil contamination (15 and 20%) can be used for low load bearing engineering application such as landfill layering and production of bricks.