| According to clustering way made by Erie C. Ellis,we make reseau subarea to picture of secondary planet by 500x500 m, twelve cells were selected from an IKONOS high resolution image of Jintang county and Jianyang City, Sichuan province, as samples representative to study change of element flux on village landscape ecosystem between 1945 and 2002 and the soil phosphorus spatial simulate analyse and relativity analyse The results are obtained as following:1, With the increasing of population and scale extends of breed,the gross of C, N, P descended from 147.03kg·a-1 28.6kg·a-1 3.84kg·a-1 in 1945 to 83.69kg·a-1, 16.28kg·a-1, 2.18kg·a-1.But in integer sight ,the gross of C, N, P is increased three time.2, There are evident differences in industrialization former and later in the hilly area of the middle Sichuan basin. In industrialization former, channel mud and manure played important role in fertilizer of farmland, content of nutrient is very low.Now fertilizer and manure played important role in farmland.But because fertilizer was applied too much in industrialization former, content of the C is twice of now. The N is twice of industrialization former because fertilizer was applied. There is no different in two period of the P,but in gross ,the content of nutrient of now is far higher than in 1945.In two period ,the more reclaim straw ,the less returning the farmland.3, There is no different in fuel and energy sources using in gross in industrialization former and later,the crop straw and fossil energy sources is main in kinds of fuel andenergy sources in now .but in industrialization former ,the crop straw is main.the content of N is 67.89Kg·HH-1·a-1 in industrialization former,but it is 39.87Kg·HH-1·a-1 now,but the content of C and N is the same in two period .because the increase of population ,so the gross of C and N is higher than industrialization former.4, The vary is very largly of the flux of C, N, P from-66.09kg·HH-1·a-1, -3.55kg·HH-1·a-1, 0.05kgHH-1·a-1 to 2.08kg·HH-1·a-1, 94.65kg·HH-1·a-1, 47.35kg·HH-1·a-1, the flux of three elementis increased very much and N of increased is most.N of put into is 315kg/ha,it is higher 220kg/ha than international, standard warn line,Result in the pollution of the agricultural surface source.5, It is obtained from the modeling analysis of phosphorus spatial distribution that the spatial variations of phosphorus are fairly fitted with Spherical, Gaussian , Exponential and cavity four model, and their spatial autocorrelation degrees are different. Total phosphorus mainly accord with Exponential and Spherical model, R08_C06, R08_C15,R13_C14 have intensified spatial autocorrelation, the degree of spatial autocorrelation of the others are weak, available phosphorus accord with the four model, besides R13_C14 have intensified spatial autocorrelation, the degree of spatial autocorrelation of the others are weak.Some values and modeling parameters of soil phosphorus have strong correlations with village landscape structure, which are followings:1) The way of different land use and structure index has significant effects on soil phosphorus. There are significant or highly significant positive correlation between fragment index of land use and soil phosphorus range and nugget.Fragment index of land use in four model landscape index have highly significant positive correlation with average value of total phosphorus , have highly significant positive correlation and biggish positive correclation,and highly significant positive correlation existed with nugget of total phosphorus.2) The all different landscape structures of landform have effect on spatial distribution of soil phosphorus to a degree, the diversity index of terrain and variance index of total phosphorus has highly negative correlation; the diversity index and fragment index has significant correlation with range of phosphorus.3 ) There is highly significant positive correlation between fragment index of soil paddy and nugget ratio of total phosphorus . the others landscape structure index and spatialdistribution modeling parameters of soil phosphorus has unsignificant or highly significant correlation.
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