Changes Of Landscape Pattern And Soil Organic Carbon Stock In The Upper Reaches Of The Liusha River

Using GIS,the indexeses of diversity,evenness,fragment,abruption and fractal dimension,have been chosen to analyze the landscape pattern changes and its influencing factors in the upper reaches of the Liusha River with reference to the land using map in 1982 and 1994 and the remote sensing images in 2007.And by applying landscape Ecotope system,within a dedicate scale,this thesis studies the relationship between the changes of SCOP and landscape patterns of the upper reaches of Liusha River from 1982 to 2007.The results of the study are as follows.In the researched area in the year of 1982,the amount of SOCD is between 3.07-16.35 kg/m~2,with the average of 7.35 kg/m2.It reaches its highest amount in the topography of slope,and the largest SCOP is found in the paddy fields and the dry land among all the different land use.The amount of SOCP is between 0.40-451.78×10~5kg,with the total weigh of 2.91×l0~8kg.A comparatively large SCOP is found in topographies including gradient,easy gradient and flat,and SCOP of dry land under differentland use is far more larger than that of others.In the researched area in the year of 2007,the amount of SOCD is between 0.63-18.13 kg/m~2,with the average of 6.29kg/m~2.Likewise,its highest amount is also found in the topography of slope,and the largest SCOP is found in the paddy fields among all the different land use.The amount of SOCP is between 4.69-570.01×10~5kg,with the total weigh of 3.15×10~8kg.The largest SCOP is found in the topography of gradient,and SCOP of dry land under different land use is also far more larger than that of others.In the 25 years from 1982 to 2007,the changing tendency of SOCP in the topsoil and the deep soil is the same.SOCP within 0-30cm increases from 1.43×10~8kg to 1.82×10~8kg, and it rises from 2.91×10~8kg to 3.15×10~8kg in the deep soil.During 1982 to 2007,the landscape area that contains woodland,bushes and paddy fields increases,while the landscape area of grassland and dry land decreases.The changing ranges of the changing tendency of SOCP within every landscape types are quite close,while the change of average of SOCD and the change of its area are the opposite.It is obvious that area of dry land and paddy fields,and its average SOCD and SOCP are both higher than that found in other patterns.As the decreasing of the indexeses of diversity,evenness,a reducing has been found in the indexeses of fragment,and the SOCP rises in the upper reaches of Liusha River.The dry land and paddy fields both share the patterns that the most numbers of small blocks and the lagest area of big blocks.Among each pattem,the abruption of small blocks and the fractal dimension of big blocks are both the largest,what's more,the total amount of average SOCD of big blocks is comparatively larger.Comparing the two indexes,the relevance between abruption and SOCD is lower while there is a closer connection between Fractal Dimension and SOCD.When the Fractal Dimension shows a significant change,its SOCD changes correspondingly and a negative correlation in general is presented.