Study On The Variability Of Soil Organic Matter And Entire Nutrient

Faced with the deteriorating ecological environment, desertification has become the threat of global ecological security, the need to solve environmental problems. Soil nutrients and vegetation cover, land degradation mutual coupling, the study of soil nutrients and soil desertification process of a dynamic relationship between changes in soil structure, prevent soil erosion, desertification and stable oasis ecological environment is of great significance, especially for the fragile ecology of the oasis zone -- Transitional zone of soil organic matter, nutrients of the entire space-time changes in the law and causes of the research is of great significance.In this paper, Xinjiang's Hotan region Wada, Moyu, Luopu three counties (and the Hemoluo) edge of the oasis and the transitional zone of soil samples for the study, Collecting a total of 250 soil samples, of which section 13 (7 Oasis Group, the transitional zone 6). Over the 1980s, Hotan region soil based on census data, Use of statistical software for the study area under different degradation gradient (restoration project) of soil organic matter, nutrient content of the whole of comparative analysis, the following major conclusions:(1) of soil organic matter content of the study area in 18.14g·kg-1-1.76 g·kg-1 between the average value of 9.95g·kg-1, at a very low level. Compared with the 1984 average increase of 1.92 g·kg-1; soil nitrogen content between 0.909%-0.007%, average0.272%, at the very low level. Total phosphorus content in 4.579-1.093 g·kg-1, and mean to 2.336 g·kg-1, in the middle class. Overall potassium content than other nutrients significantly high. Coefficient of variation of soil nutrients in 89.3%-3.61%, total nitrogen and total salt belong to the strength of variation, potassium, total phosphorus belong to the weak intensity variation. Total phosphorus, potassium and organic matter for the variation in the weak, the coefficient of variation are 33.31%, 29.48%, 38.29%,pH coefficient of variation was 3.61 percent, a weak variation. All of soil organic matter and nutrients are subject to normal distribution. Hotan region due to soil texture light of the heavy sand, clay small, water-poor soil fertility, soil salinization of serious, local nutrients inherent "lack of organic matter, less nitrogen " features have not been changed , and potassium in the soil also greatly reduce the degree of.(2) of soil nutrients complement each phase of suppression, has a very good relationship. One of soil organic matter and total phosphorus was a significant positive correlation with the total nitrogen was significant positive correlation, and the overall trend line. pH value and total phosphorus was related to relations with the organic matter content was negatively correlated. Potassium and phosphorus, showed significant positive correlation.(3) in the gradient level, the degree of aging oasis soil and soil fertility level of villages to cities and towns as the center of a concentric circle. Oasis - a transition zone of soil fertility decline distribution ladder. In the vertical gradient, the oasis of soil organic matter content of trends similar to "S"-type distribution, total phosphorus-such as changes in trends "W"; vertical changes in the nutrient content of nutrients for the topsoil is greater than the bottom; oasis within the nutrient content of more than Transitional zone. Leaching of nutrients weaker, with two landscape (Oasis, the transitional zone) variation of soil nutrients mainly in the larger impact of human activities, 0-40 cm.