Paddy Soils Cropping Systems Spatial Distribution Optimizing In County In Hilly Region Of Red Soil--A Case Of Fengxin County In Jiangxi

Cropping systems reform and development in hilly region of red soil is a hot discussion among experts both home and abroad for a long time. The study in cropping systems spatial distribution optimizing is few, and combing quantization model, economy theory and modern information technology is few too. The research result in the case of Fengxin County in Jiangxi Province can provide cropping systems reform and spatial distribution optimizing decision-making not only for Fengxin County, but also for other counties in hilly region of red soil. This paper has both academic and practical significance.For such reasons, the author investigated comprehensively on cropping systems and agriculture development in Fenxin County from 2002 to 2004, using mathematics model and GIS, discussed the cropping systems characteristic and development orientation and optimized the cropping systems spatial distribution. The data were collected from literature, questionnaires to experts and farm households, on-site investigation and field experiments. The main results are as follows:1,Because of inconsequent exploitation and management of the resources, rapid increasing population in hilly region of red soil, the stress on soil, deterioration of farmland ecological environment and soil gleization become more and more serious. Natural features , water and thermal resources and species are abundance. The territorial advantage of this region is a favorable condition for the cropping systems adjustment.2 , Through one season rice multiple cropping system research in Fengxin County in Jiangxi province, seven oil sunflower varieties, two forage rice varieties, two succulent varieties , four forage grasses varieties and two vegetable varieties had to a certainty expending value. Through paddy soils new cropping systems field experiments, forage grasses-late rice, oil sunflower-late rice and etc cropping systems had to a certainty expending value.3 ,The new cropping systems were multi-objectively evaluated through gray relationanalysis. The analysis results were consistent to the practice and the visual evaluation of peasants. The analysis results through gray relation can provide decision-making for extending the new cropping systems.4, Hilly region of red soil cost comparative advantage index and yield per hectare comparative advantage index in Fengxin County were measured. Strong comparative advantage crops late rice and cotton should be enlarged. Infirmness comparative advantage crops early rice, medium rice and rapeseed should be maintained. Strong comparative disadvantage crops soybean and peanut should be reduced.5 , Cropping systems were optimized by linear programming model. Decision variables were cropping systems. Comparative advantages of the main crops were added to the constrain condition. Objective function was making the income maximum. The total income was 269.17 million yuan comparison to 235.91 million yuan before the adjustment, increased 14.1%.6, Using the model of material source, the cropping systems adaptability to village planting units in Fengxin county were evaluated, village planting units digitizing and attribute database were constructed based on the spatial analyzing capacity of GIS. Then the village cropping systems spatial distribution project was elicited, as well as the function of the cropping system spatial distribution optimization.