Issues on Environmental Changes and Sustainable Development in a Tropical Agricultural Watershed

Abstract

Investigation results of four issues on environmental changes in Cidanau watershed, which have been originally found through our cooperative research, are introduced and discussed: (1) water level and environmental changes in Rawa Danau, (2) variable acreage of cultivated paddy fields depending on preceding precipitation, (3) does paddy field increase or decrease water resource?, and (4) changes in nitrogen cycle due to prevalence of chemical fertilizer. Whereas former two are special issues important in Cidanau watershed, the results of latter two issues must be general and commonly important among tropical agricultural watershed where paddy field spread. Necessary measure for sustainable development on each issue is also discussed.