On the Health Diagnosis of the Land Use System Based onProjection Pursuit Model in Chengdu

11 counties in the first and second layers of Chengdu were selected as our empirical research subjects. By the introduction of projection pursuit model, and with the help of genetic algorithm, a probe was made of the land use system for its health conditions, and thus to find out about its characteristics in spatial distribution as well. The results showed that:(1)the projection pursuit evaluation model, optimized through the use of the genetic algorithm, was found to have a rather strong adaptability in the evaluation of land use system, and results thus obtained were quite objective and reasonable;(2)in 2011, the overall health level of the land use system in the first and second layers of Chengdu is satisfactory, regions with a projection characteristic value within the range of 0.9145～2.1301 and the relatively healthier regions are largely found in the inner circle of the city, and regions with a poor health condition in land use are mainly found in the south and north of the areas under study. The findings show that to improve the health of the land use system, priority should be given to the following aspects: the strict implementation of the policies concerning the protection of arable farmland; the improving of the Land reclamation rate; the proper use of the allocated construction land; the establishment of a market-based land resources use system; adequate emphasis placed on the job of environmental protection and the enhancement of pollution prevention.