Study On Quantitative Ecology Of Corn-growing Regions In Shanxi

Corn, having strong adaptability and wide planting range around the world, is one of the important agricultural and economical crops. With the quick development of the economy and population explosion, the use of corn in industry and agriculture become more and wider, the study on how to increase the corn yield and quality has very important significance.Based on the corn yield of Shanxi, the distribution characteristics of ecoclimate factors and corn yield in Shanxi were studied by PCA and DCA. The regionalization of corn-growing region was studied by GIS. Moreover, the relationship between corn yield and ecoclimate factors during corn growth periods was studied by using integral regression analysis. The aim of this paper was at making good use of the ecoclimate resource and providing the basis for the high yield and quality of corn.Combine the statistics and formula model, the corn yield dynamics and distribution were analyzed. The real corn yield was divided into 2 parts: tendency yield and climatic yield. The tendency yield calculated by straight line moving average method, but the climatic yield fluctuation was bigger.The ecoclimate factors in the corn-growing regions were analyzed by PCA, and PCA comprehensive evaluation model was got. The ordination results were that first axis expressed the variation of sunshine and temperature factors, the second axis expressed the variation of water-condition factors, which was accordant with the actually condition. The corn climatic yield was analyzed by DCA, the results showed that the distribution of corn yield was strongly accordant with the distribution of ecoclimate, the ordination could reflect the relationship between corn yield and ecoclimate preferably.Based on the ordinate score from PCA, the corn-growing regions were divided into five ecoclimate areas, which were (l)corn-growing region of northwestern Shanxi, (2)corn-growing region of Datong basin and north Luliang Mountains, (3)corn-growing region of Taihang Mountains and Xinzhou basin, (4)corn-growing region of Taiyue Mountain, Taiyuan and Shangdang basins, (5)corn-growing region of Zhongtiao Mountains, Linfen and Yuncheng basins.By the integral regression analysis, the relationship between the ecoclimate factors and the corn yield of the 18 counties or cities was analyzed with a unit for 10 days. The result showed that: Relative to the corn requirement, the air temperature and rainfall was on the low side on the seeding stage in northern Shanxi; the air temperature and rainfall was on the low side from jointing stage to tasseling stage; the rainfall and sunshine were on the low side on filling stage; but the total sunshine hours were relatively abundance in the whole life of the spring corn. In southern Shanxi, the total sunshine hours were also abundance for the summer corn. For the summer corn in Linfen Basin, the rainfall was proper but the sunshine was not enough, in Yuncheng Basin on the middle and the later of the life the rainfall was too much and the sunshine was not enough too.