Study On The Soil Fertility Spatial Variation After Land Consolidation In JinChengShi Of Shao Yang County

Land consolidation obviously damaged cultivated land, especially cultivated horizon, which resulted innutrient deficiency and fertility quality in cultivated land. This paper takes land consolidation area in Shaoyang Jinchen town as the research object, the nutrient features was analyzed and soil fertility quality was evaluated by principal component analysis, and the spatial variation characteristics of soil nutrient and fertility was conducted using GIS technology and geostatistics method, furthmore, selected the undigested and digested land by the chronosequence approach, studied the effect of land consolidation on spatial variation of soil nutrient and fertility, the main results are as follows:(1) Soil nutrients have moderate variability on land consolidation area. Geostatistical analysis results show that the nine soil nutrient indexes’coefficient of nugget range of 50.1% to 99.8%, with moderate spatial autocorrelation, and spatial variability is caused by both structural factors and random factors. According to soil nutrient Kriging spatial interpolation, the spatial distribution of soil properties and nutrient content act as follows:the distribution of TNV AN is more dispersed, other indexes presents strip and continuous distribution. The fragmentation of soil nutrients index range from 0.36 to 0.77, where total potassium is highest for 0.77, organic matter is lowest for 0.36. This result is in accord with spatial distribution of soil nutrient index.(2) Soil integrated fertility index ranged from 0.076 to 0.697.The soil integrated fertility is intermediate variability, and nugget effect reaches 41.55%.The spatial of soil integrated fertility appears in block patterns. The eastern of soil integrated fertility with high content and the western with low content. Soil fertility degree of fragmentation is 0.333, 0.23～0.33 with large equivalent area, the range of 0.07～0.17 and 0.47～0.70 is no distribution. It shows that land consolidation area is at low level of soil fertility quality.(3)Land consolidation in soil pH, organic matter and other nutrient index change is obvious. Undigested land of soil of pH, organic matter, total nitrogen and other nine indicators were higher than digested land, which undigested land of the soil pH, total nitrogen, slowly available potassium significantly (p< 0.05) higher than digested land. The geostatistics results show that the coefficient of nugget of undigested land changes in the range of 0.688 to 0.999, while digested land range of 0.808 to 0.999, the variability is relatively constant, and the spatial correlation is poorly dependent. Land consolidation lead to the reduction of variability of pH, organic matter, total nitrogen, total potassium and alkali-hydrolysable nitrogen, while the increasing of others. The spatial distribution of undigested and digested land is roughly the same. The soil nutrient of digested land with low contents and much extreme value, the spatial pattern has taken great changes. A large range of undigested land fragmentation is large and digested lands’range small, mainly related to spatial distribution pattern.(4) digested land of soil integrated fertility index averages of 0.36, the standard deviation is 0.14, undigested land of soil is 0.54, the standard deviation is 0.21. Undigested land of soil integrated fertility index than digested land significantly (p< 0.05) was 50.00% higher. That land consolidation resulted in the decrease of soil integrated fertility index and soil fertility decline in the quality. Relative to undigested land, the and digested land of soil integrated fertility index standard deviation is relatively smaller, shows that digested land of soil integrated fertility index change smaller. Undigested/digested land of soil integrated fertility index both has intermediate variability. The coefficient of variation of digested land is 0.27%, higher than undigested. It shows that land digested causes coefficient of variation of soil fertility index increased. The coefficient of nugget of digested land is 0.032, higher than undigested. After land digested the spatial correlation is getting weaker. Part of spatial distribution pattern, undigested land with high content has many contour map spots, digested land has mass extremum. The main reason is that land digested peeled the surface of soil, during the filling process, it changes soil fertility quality. It shows that land digested decreases soil integrated fertility index and soil fertility quality.