Title: Sustainable Traditional Agriculture in the Tai Lake Region of China
Abstract: Traditional agriculture in China's Tai Lake Region sustained high productivity for more than nine centuries. This article examines the ecological basis for this high long-term productivity in a historical context, with a focus on the role of nutrient limitation. From 1000 AD to the 1950s, agricultural technology remained basically unchanged, as did the yields of rice, wheat and other crops. Still, total grain production and net farm income increased over time, as a result of increased multiple cropping, expanded mulberry/silk production, and the intensified use of organic fertilizers. Without degrading soil resources, continuous intensive farm management supported the nutritional and other needs of the rural population, which grew to nearly ten people per hectare of cultivated land by the 1930s. Ecological limitations to human carrying capacity that seem apparent in the mid 1800s appear to have been overcome since the 1960s by chemical nitrogen subsidy of agroecosystems. Human populations are now nearly twice their traditional maximum, and the region remains one of the world's most productive agricultural regions thanks in part to heavy fertilizer applications that have changed nitrogen from a limiting nutrient to a potential source of pollution. Whether these high inputs and/or other agricultural technologies will continue to sustain food self-sufficiency for the region's farmers remains to be seen. The high long-term productivity of Tai Lake Region agroecosystems make them ideal for study of the ecological basis for sustainable agriculture.