[Objective] This paper aims to empirically analyze the situation of fertilizer overuse in China, considering that fertilizer, important for China＇s crop production, has brought serious environmental pollution to Chin...[Objective] This paper aims to empirically analyze the situation of fertilizer overuse in China, considering that fertilizer, important for China＇s crop production, has brought serious environmental pollution to China due to over application. [Method] Based on field survey data in four provinces of China, the magnitude of fertilizer overuse at farm level was empirically analyzed with Cobb-Douglas Produc- tion Function Method and profit optimization theory in the research. [Result] The resuits show that by average, 110.5 kg of chemical fertilizer were applied per mu of land, and 46.9 kg fertilizer was overused, occupying 42.5%. [Conclusion] There is large potential to reduce the overused amount and it is of great importance to re- duce fertilizer overuse effectively, which needs further intensive study.展开更多
Greater Zab is the largest tributary of the Tigris River in lraq where the catchment area is currently being plagued by water scarcity and pollution problems. Contemporary studies have revealed that blue and green wat...Greater Zab is the largest tributary of the Tigris River in lraq where the catchment area is currently being plagued by water scarcity and pollution problems. Contemporary studies have revealed that blue and green waters of the basin have been manifesting increasing variability contributing to more severe droughts and floods apparently due to climate change. In order to gain greater appreciation of the impacts of climate change on water resources in the study area in near and distant future, SWAT （Soil and Water Assessment Tool） has been used. The model is first tested for its suitability in capturing the basin characteristics, and then, forecasts from six GCMs （general circulation models） with about half-a-century lead time to 2046-2064 and one-century lead time to 2080-2100 are incorporated to evaluate the impacts of climate change on water resources under three emission scenarios： A 1 B, A2 and BI. The results showed worsening water resources regime into the future.展开更多
文摘[Objective] This paper aims to empirically analyze the situation of fertilizer overuse in China, considering that fertilizer, important for China＇s crop production, has brought serious environmental pollution to China due to over application. [Method] Based on field survey data in four provinces of China, the magnitude of fertilizer overuse at farm level was empirically analyzed with Cobb-Douglas Produc- tion Function Method and profit optimization theory in the research. [Result] The resuits show that by average, 110.5 kg of chemical fertilizer were applied per mu of land, and 46.9 kg fertilizer was overused, occupying 42.5%. [Conclusion] There is large potential to reduce the overused amount and it is of great importance to re- duce fertilizer overuse effectively, which needs further intensive study.
文摘Greater Zab is the largest tributary of the Tigris River in lraq where the catchment area is currently being plagued by water scarcity and pollution problems. Contemporary studies have revealed that blue and green waters of the basin have been manifesting increasing variability contributing to more severe droughts and floods apparently due to climate change. In order to gain greater appreciation of the impacts of climate change on water resources in the study area in near and distant future, SWAT （Soil and Water Assessment Tool） has been used. The model is first tested for its suitability in capturing the basin characteristics, and then, forecasts from six GCMs （general circulation models） with about half-a-century lead time to 2046-2064 and one-century lead time to 2080-2100 are incorporated to evaluate the impacts of climate change on water resources under three emission scenarios： A 1 B, A2 and BI. The results showed worsening water resources regime into the future.
