Spatial-temporal Variation Of Terrace Soil Nutrients In The Three Gorges Reservoir Area

This research take Wushan county of Chongqing city as an example, studied the spatial-temporal variation of soil nutrients in the tree Gorges reservoir area. Under the guidance of soil nutrients theory, Through field survey sampling and laboratory chemical analysis method combined, measured Terrace soil nutrients in different land use patterns,different slope and different Terrace age of Wushan County of Chongqing City, The results are as follows:(1) a comprehensive analysis of Terracing soil nutrients of Wushan County shows: the content of soil organic matter in the lack of state, Soil total nitrogen and rapidly-available potassium content in mid-level, soil total phosphorus in between lack of and very lack, Total K content higher,in the rich state and the available phosphorus is in the lack state. The variation of nitrate content had the largest coefficient, as186.43%, Belong to strong variability. Other spatial variability of nutrient content were moderate intensity variation,Coefficient of variation were available phosphorus85.70%, potassium 36.99%, ammonium N35.65%, total P29.24%, organic matter 25.75%, total nitrogen 20.91%. The smallest variability is the total K, only 20.09%.(2) According to correlation analysis results, the correlation coefficient of soil organic matter content and total nitrogen, available phosphorus, potassium and phosphorus highly significant levels, relationship with the total potassium were significant negative correlation level. That soil organic matter and total nitrogen, phosphorus, potassium and total phosphorus content was positively correlated, that is, high organic matter content, soil total nitrogen, available phosphorus, potassium and total phosphorus also followed increased.(3) There are quite obvious for the soil nutrient content in different land use patterns. The specific performance as follows, the diversification of organic matter and total nitrogen is : Forest and grassland>vegetable field>cornfield>orchard; The diversification of nitrate is: forest and grassland>cornfield>vegetable field>orchard; Ammonium N vegetable field>forest and grassland>cornfield>orchard; Total P cornfield>vegetable field>orchard>forest and grassland; Available phosphorus grassland>cornfield>vegetable field>orchard; Total K cornfield>orchard>vegetable field>grassland; Potassium forest and grassland>cornfield>vegetable field>orchard.(4) The analysis for the soil nutrient content in different landscape position, found that, the diversification of soil organic matter, total nitrogen, nitrate nitrogen, ammonium nitrogen, total phosphorus, available phosphorus, available potassium is: hilltop