This paper applies von Thunen's land-use theory with approach to labor location to examine spatial patterns of conservation and land quality. It is based on long-term fieldwork in West Jilin, China, an area that suffers severe land degradation. Statistical data were collected in a four-year project from 1993 to 1997, involving 1,801 fields fanned by 307 families from twenty villages, and analyzed using correlation, regression, and analysis of variance. The distance of labor from agricultural fields is found to be the main contributor to the prediction of conservation and land quality, while effects of market distance are also significant to three of the eleven variables. Nearby fields have more organic inputs, better tree coverage, and better water supply. They are also less affected by soil-exhausting crops and tend to be farmed with traditional environment-friendly techniques. Distant fields are disadvantaged in all these aspects, though they benefit more from crop rotation. As a result, land quality-as measured by depth of soil humus, net income, and farmers' evaluations of land-quality changes-decreases with distance from labor location. Four types of land quality zones were found around labor centers: enhancing, conserving, degrading, and exhausting. The findings imply that agricultural intensification is associated with land improvement in near fields, while it causes land degradation in remote fields. The research calls for further applications of the von Thunen theory and the labor-location approach to environmental problems. It suggests that policymakers need to look at environmental degradation from spatial perspectives, specifically by allowing farmers to live closer to their fields in order to increase conservation and curtail land degradation.
