Longjing tea from bluish to deep green after steeping. Before infusion, higher quality Longjing teas have a very tight, flat shape and light green color. A study by Wang and Ruan (2009) found that one aspect of the perceived low quality of Longjing teas was a higher concentration of chlorophyll, producing a darker green color. The study revealed that free amino acids and theanine concentrations contribute positively to what is perceived as a good taste. Longjing tea was granted the status of Gong Cha, or imperial tea, in the Qing dynasty by the Kangxi Emperor. According to the legend, The Kangxi Emperor's
Tianchi basin passes. The rain gauges were conical or barrel-shaped with one being installed at each provincial and district capital in China. In the treatise, Qin Jiushao also discusses how point measurements were converted to real averages. These averages were important as they postulated indicators of natural disasters such as flooding, since river flooding has always been a problem in China. Tianchi basin As precipitation was for important agriculture and food production, the Song Chinese mathematician and inventor Qin Jiushao developed a precipitation gauge that was widely used in 1247 during the Southern Song dynasty to gather meteorological data. Qin Jiushao later