The Research Of The Topsoil Physical And Chemical Properties Of Cotton Lands In Weigan And Kuqa Oasis

In this paper, to explore the topsoil of cotton land’s physical and chemical properties change driving mechanism, the cotton land’s topsoil in Weigan and Kuqa Oasis as a object of study, it has important significance for rational utilization and agriculture sustainable development of soil resources in the research region and arid area of Northwest China in our country. In order to better compare the cotton land topsoil particle size characteristics and changes of organic matter, total nitrogen, total phosphorus and total potassium content, using the relevant Soil geography-based theoretical knowledge and research methods, cotton land topsoils and other land pattern topsoils samples were collected in the study area, and by the systematically testing the indexes of soil physical and chemical properties, including soil particle size, soil salinity and soil nutrient ions (organic matter, total nitrogen, total phosphorus, total potassium) of experimentally determined, and through using the data processing analyze of space heterogeneity, correlation, summarized the following characteristics of cotton land topsoil grain size, salt ions and nutrient in the study area, such as:(1) Cotton land topsoils in the study area is mostly pink sand, sandy loam, spatial heterogeneity was shown in the short term the impact of human activities on soil particle size is limited, and natural conditions such as soil parent material, terrain effects on soil texture, such as very large. With the increase of land utilization periods, the granularity of the topsoil of cotton planting in the study area showed gradually coarsening trend.(2) Research district planting cotton land topsoil salt ions content is high and accumulation is strong, soil salinization phenomenon is more serious, for the more, heavy salinization and light salinization soil relatively less, soil for sulfate type saline soil, this phenomenon not only have closer relationship with natural conditions but also have very close relationships with people’s cultivation way, the average content of salt ions in cotton topsoil is higher than other utilization land topsoils. With the increased of the land utilization periods there was a good correlation with Ca2+in cotton land topsoil salt ions, and the correlation with K+,Na+is after ca2+(3) In this study area nutrient content of topsoil is relatively low, affects of artificial cultivation, land use patterns and land use periods also reduce the nutrient content, let the soil has characteristics of sierozem. And the coefficient of variation and nutrient content of cotton land topsoil are higher than the other cultivated land; 15years of continuous cotton cropping land topsoil’s organic matter and total nitrogen, total phosphorus, total potassium correlation tends to be good, the correlation is reduced by more than15years later.(4) Although the soil organic matter and soil particle size did not reach the significant correlation, but the soil organic matter have a well correlation with silt and sand of the cotton land topsoils.(5) Soil organic matter has reached significant level with K+, Na+in the bilateral inspection0.01in topsoils, has reached a significant level with Cl-in the bilateral inspection0.05in the cotton land topsoils; p and K has reached significant level in the bilateral inspection of0.01in other cultivated land and10years of continuous cotton cropping land topsoils, and the salt ion of each period of cotton land topsoil did not reach significant level.