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The rapid development of China's economy and urbanization has given rise to noticeable environmental problems, among which the change of air quality has received extensive attention. The panel data of PM2.5 (particles with an aerodynamic diameter of 2.5 μm or less) in 343 prefecture-level cities in China from 1998 to 2016 were statistically analyzed to reveal the characteristics of the temporal evolution and spatial variation of China's air quality in the past two decades. The results show that: 1) the overall deterioration trend of air quality is obvious throughout the country. The variation trend of PM2.5 was divided into three phases: rapid-growth phase (1998–2007), lag phase (2006–2011) and mildly-incremental phase (2012–2016), with their average growth rates of 7.19%, −3.59% and 0.52%, respectively. 2) The spatial difference of PM2.5 values in China increased significantly with time. Since 2003, the high-value area in the east has expanded rapidly, and polarization became much more pronounced. The change rate of PM2.5 is high in the east and west and low in the middle. The change rates of most areas in the west exceed more than 80%, and in the east lie somewhere between 40% and 60%. In the midlands, the change rate is not large and some regions even show a negative growth. 3) The change rate of PM2.5 is also high in areas with higher values. However, in regions where the change rate of PM2.5 is high, the value of PM2.5 is not always high. The high change rate is mainly attributable to the low base value of PM2.5 and the cities concerned belong to sensitive areas. 4) According to the PM2.5 warning index, the number of strong, medium, weak and non-warning areas in China is 45, 85, 159 and 54, respectively.

analysis on water quality and phytoplankton community structure was carried out throughout the year of 2015. Nutritional status of Fuxian Lake was evaluated by means of biological evaluation method and TSIM. Results show that, there are totally 8 phylum 66 categories and 101 species of phytoplankton, green alga, diatom, and blue-green algae as major dominant species. With this year, seasonal changes happened in phytoplankton community, green alga and diatom as principals in spring, green alga and blue-green algae as principals in summer, green alga, diatom and blue-green algae as principals in autumn, green alga and blue-green alga as principals in winter. Results of redundancy analysis show that, the greatest influence water quality factor of phytoplankton community structure in Fuxian Lake is SRP concentration. Water quality factors in spring include DO and SRP concentration, TN and SRP concentration in summer, SRP concentration and pH in autumn and winter. Results of eutrophication evaluation show that, evaluation results of biological evaluation method and TSIM are basically the same but there still exist differences. It can be seen by combining with two methods that Fuxian Lake now is still in oligotrophic stage but it has characteristics of poor medium nutritional type in transition stage.

A research stream known as prospect theory describes how decision biases lead to results that differ from those predicted by classical utility theory (Kahneman and Tversky, 1979). Prospect theory hypothesizes that individuals will experience potential losses more intensely than potential gains, and will be more risk‐seeking in loss situations, while more risk‐avoiding in gain situations. This study includes 948 participants from the PRC and 318 students from the USA. All of our attempts to replicate these findings in the Peoples’ Republic of China have revealed a different pattern. Chinese subjects consistently demonstrated risk‐seeking preferences, both in gain and loss situations.

The 1hm2 integrated constructed wetland was built on the northern bank of Lake Fuxian, Yunnan Province, for reducing and controlling the development of its eutrophic state. Efficiencies of nitrogen removal of the wastewater from the Yaonigou river were investigated by using the integrated constructed wetland including the function parts of precipitation pond, oxidation ponds, constructed wetlands subsurface flow and surface flow. The results demonstrate that there was a very high capacity of nitrogen removal in the wetland. The average hydrologic budget was 437 mm/d. The average nitrogen loading was 3. 315 g/(m2 · d) . The nitrogen retention was 1. 91 g/(m2 · d) . Nitrogen retention through plant uptake was 142 mg/(m2 · d). It was about 7. 5% of total retention. The average removal rates of the constructed wetland for different species of nitrogen were 62. 7% (NOx-), 53. 8% (NH4+ ), 62. 4% (TON) and 57. 5% (TN), respectively. The average removal rates of nitrogen were 39. 4%, 18. 5% , 10. 6% and 3. 6% in the surface flow constructed wetland, the oxidation ponds, the subsurface flow constructed wetland and the precipitation pond, respectively.