Study The Spatial Of Soil Properties In Different Level Stream Of Three Gorges Reservoir Typical Basin

The Three Gorges Project affects centralizely in the middle of the Three Gorges Reservoir where human activity is intensive, and massive lang has been farmed in the steep slope, account for 34% in slope land,lead to serious soil erosion. Watershed is the typical Geographic Pattern in the middle of the Three Gorges Reservoir,that Industrial Distribution and Resource Utilization is weak,and Agricultural Production lack of long-term plan.We will analysis the spatial distributing of soil nutrition and the influencing factors by the measure of soil nutrition content of Wu-qiao- watershed in different level stream including organic matter, nitrogen, phosphorus, potassium. The detailed targets in this study were:1) The spatial distributing of soil properties in different level stream of watershed;2) The relations of soil properties in different level stream of watershed; 3) combined with the spatial distributing of soil properties in watershed and landscape ecology to provide reasonable planning.The main research results were listed as follows:I. The soil nutrient overall condition in study areaThe soil organic matter content is 6360-37910mg/kg in different level stream, soil organic matter content in 1th level stream,the average is 16982.5 mg/kg that is lower than 2th and 3th level stream.Soil total nitrogen content is between475 mg/kg to1427mg/kg in the Watershed,and the 3th level stream is the highest one, the organic matter tendency is obvious.Soil total potassium congtent is between 9290 mg/kg to 18470mg/kg,and its distribution is not obvious. The total phosphorus content is low, between251 mg/kg to1029mg/kg,the available phosphorus tendency is obvious.II. The spatial distributing of soil texture in different level StreamThe content of sand is high between 30% to 69%. The content of sand in different level stream,lth level stream>3th level stream>2th level stream. Sand content in lth level stream which average is 48.15% higher than other one, sand content of the sandy soil is 50%.The congtent of soil nutrient is low,and will loss easily.we should to strengthen the Soil and Water Conservation,and to increase the use of organic fertilizer.The content of silt is between 29%to 65% in different level Stream,3th level stream>2th level stream>lth level stream,its tendency is obvious. The content of clay is beween 2%to10%,2th level stream >1th level stream>3th level stream.3th level stream is the lowest.we should to fertilize reasonable. The content of physical clay tendency is obvious,3th level stream>2th level stream>lth level stream.III. The spatial distributing of soil nutrient in different level streamThe content of soil total nitrogen, fast-acting phosphorus and organic matter tendency is obvious in different level Stream,3th level stream>2th level stream>lth level stream. The soil nutrient in 3th level stream is best one,show that the eara of 3th level stream is important in the Watershed. The congtent soil total potassium,2th level stream>3th level stream>lth level stream. The soil potassium distribution is uneven, which has been effected by Soil Parent Material. The spatial distributing of soil nutrient in different level Stream is important,it is key link to partition ecological system function and to distribute soil and water resources reasonably.IV. The relations of soil properties in different level StreamThe soil organic matter has related with fast-acting nitrogen,total nitrogen,fast-acting phosphorus,the correlation coefficient is 0.693,0.747,0.373.And soil total nitrogen has related with fast-acting nitrogen and fast-acting phosphorus.We should pay attention to the function and influence of soil potassium. The soil organic matter related with soil total nitrogen and ast-acting nitrogen in different level stream.The correlation is obvious in lth level stream.Maybe other level stream has been effacted strongly,so that the spatial distributing of soil nutrient is unbalance. And we will know the reason of the difference between soil fast-acting nitrogen to organic matter tendency.We should to know the relations of soil properties and to plan ecological agriculture in the watershed.V. Functional area of an agricultural in the watershedUse of landscape ecology theory and methods,combined with the basin characteristics of the vertical distribution of natural resources, while emphasizing the importance of river in the basin, to analysis the spatial distribution of soil properties in different level stream. Wu-qiao-he watershed,is divided into 3 different regions that is agricultural landscape functional area, coordination of ecological restoration area and ecological control area. Binding the natural environment within the agricultural distribution, at the micro level, to layout agricultural landscape.