| The method of the artificial slope flow area was employed in the thesis for studying on erosion for different land use categories in the Foulin forest farm,located in the south- Chaohu lake,flow areas were set up in masopine plantation, broad-leaved forest,masobamboo forest and new planted land and farmland as control, all data was collected in the period of 2000～2006,and erosion situations for different forest lands and farm land were analyzed with,then mathematical models for the relationships between land use categories and erosion were built up as well.The modern technique of "3S" was used to determine the landscape pattern of study area for different periods of 1995 and 1997 respectively,and the results was checked using GPS in field to meet the demand of distinguishing precision.Some landscape index,such as patch shape index,for similar to circle,patch fractal dimension,landscape diversity H and evenness index E were computed.Based on the data of rainfall collected in the field and the mathematical models above described,the total soil erosion amount for different landscape elements and different investigation periods was computed.Then the influences on erosion for different landscape patterns were analyzed to explain the relations between different land use categories and soil erosion.Which will provide the theories and practice basis for controlling of Chaohu non-point pollution and management or planning of forest landscape pattern in the area.The results showed as the following:1,The differences for soil erosion are significance in different forest types,Based on soil erosion amount,Macobamboo forest is the lowestm,then Broad leaved forest, Massopine plantation,New planted land in order.And the new-planted land had serious erosion problem,so should make some control methods.2,The soil erosion models for different landscape use categories are:Farmland:Y=0.0003461*I3.1863,R=0.8301;New planted land:Y=0.001761*I2.5836,R=0.8592;Masso pine plantation:Y=0.005208*I2.0869,R=0.8571;Broad leaved forest:Y=6.44*10-9*I4.9715,R=0.9549;Masso bamboo forest land:Y=0.000197*I2.4731,R=0.8716。3,Only these forests which reach to certain age and certain coverage with ground litter and developed root system have good function on erosion control,the broad leaved forest and masobamboo forest have higher erosion control effects compared to others.4,Conifer forest as the background and matrix in the hill area of south-Chaohu, and new planted land is the important element,but the area for both of broadleaved forest and bamboo forest are small and they distribute fragmentally in the study area. So the former two land use categories become the major factors of erosion,their erosion modulus reach to 32.1 t.km-25,If through logistical planning for the current forest landscape,and let broadleaved forest and bamboo forest become the major element in the future,then the hill area in the south Chouhu lake will reduced soil erosion as many as 6610tBase on the present forest landscape pattern,the author make the following suggestions on non-point pollution control and forest management.1,Transformed some farmlands located at hill slope with more erosion problem to be forest land,thus to reduce sediment to Chaohu lake2,Planning more ecological forest and closing forest land in the area to enhance erosion control effects.3,Restoring forest vegetation in the wild hill lands,for that some native tree species or bamboo species with high erosion control function should be selected for reforesting;and suitable silvicultural methods should be employed to make new planted lands to close canopy in a relative short period4,Adding broadleaved trees into conifer forest to transform conifer forest to be mixed forest,then changing the present landscape which conifer forest as the background to be that with mixed forest as the background.5,The system of GIS should be built up to make a logistical management and monitor for the dynamic of soil erosion in the area.
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