The Bad Earth? China's Soils and Agricultural Development since the 1930s

Abstract

New soil data show mixed and sometimes unexpected trends in China’s tilled soils since the 1930s. Organic matter and nitrogen have declined, although more so in the populous east than in the famous erosion-prone areas. Other soil nutrients and pH have improved. The economic consequences of these changes are weighed using simultaneous-equation estimates on 1980s data. China’s average quality of agricultural topsoil has probably not declined since the 1930s. In most regions the expansion of China’s agriculture is soil-conserving. Rising incomes and industrialization may improve the soil endowment by causing shifts to soil-preserving products and practices. I. Concern about Soil Trends Conventional GDP measures misrepresent human progress by failing to value the depletion or accumulation of natural resources. There is a growing global awareness that any net resource depletion needs to be correctly measured, priced, and kept to a rate consistent with sustainable growth. Fears that economic growth cannot be sustained focus on the soil, as well as on biodiversity and on our atmospheric, forest, and mineral resources. As long as the world’s farmers keep ‘‘losing ground’’ to soil degradation and to urban-industrial use, food supplies may be threatened. The Rio Summit’s ‘‘Agenda 21’’ platform in 1992 warned that massive erosion is causing rapid loss in the fertile soil of our planet. Global maps now chart the severity of human degradation of the soil and measures of annual rates of soil loss. Official global measures of the economic value of these losses are forthcoming. 1 China stands in the spotlight of global soil-trend concerns. It has always been threatened with severe wind and water erosion, especially in the arid north and the mountain areas. China’s heroic conservation efforts, such as the Great Green Wall on the loess plateau of Shaanxi Prov