Research On Establishing Benefit Evaluation Index System Of Massive Sloping Land Conversion Program In China

Massive sloping land conversion(MSLC) program in China is one of the important governmental actions in improving eco-environment.A lot of money,manpower and material resources have been sponsored by national government and local government at several levels.Nowadays,the urgent problem needed to be researched and solved in benefit evaluation of MSLC is how to evaluate the benefit of MSLC scientifically and reasonably,which is the universal problem focused by the governments and society.Target at MSLC program in Zhongyang county,Shanxi province,the thesis analyzed effect of MSLC on soil quality and benefit on intercepting rainfall.The results showed that the biggest interception was significant in canopy of Caragana and Robinia pseudoacacia L.forests.The interception in litter was significant in Amorpha fruticosa L.and Robinia pseudoacacia L.forests,which indicated the strong water holding capability under the forests.While the interception in undergrowth herbage was significant in Platycladus orientalis L.and Pinus tabulaeformis Carr.forests,which indicated the distinct dissipation of rainfall energy in the forests.The difference of permeability was in various land conversion soil.Except for Caragana,Amorpha fruticosa L,Pinus tabulaeformis Carr.and Juglans regia,the permeability in forests was close to or excess of the level of natural meadow.The permeability under parts of tree species far exceeded the average level.The type of land conversion in Zhongyang county got significant effect in improving soil quality or hydrological characteristics.Different tree species were well targeted,so the whole effect of the MSLC program was distinct in Zhongyang county.Based on the basic database of remote sensing image recognizing and interpreting in Zhongyang county,the land utilization/land cover dynamic in this county was analyzed and assessed for six years from 1999 to 2005.The results showed that the cultivated land was decreasing year by year from 18.9% of total county area in 1999 to 12.3%of total county area in 2005.Forest land increased 3577.3 hm~2 from 24.4%in 1999 to 26.9%in 2005.The variety trend of meadow was converse with that of farmland. It increased from 1999.The meadow evolved from low cover to medium cover,from medium to high. However,parts of high cover meadow degraded to low cover meadow.It indicated a portion of meadow was ruined with development of urbanization,and land for construction was increasing year by year.In the six years of MSLC program,bare land decreased about 1000 hm~2 in the county. According to background property,main problem and local social economy condition of MSLC program in our country,index system for benefit evaluation of MSLC program was established.Benefit evaluation and value accounting was carried out by the system.Using opportunity cost approach,recovery expense approach,shadow project approach and so on,total eco-value after land amendment of MSLC was calculated in Zhongyang county,which was 615 million yuan over the last 9 years by 2008.In the total eco-value,the biggest value was 26.9%of manufacturing oxygen and fixing carbolic of forest,the second value was 26.6%of soil conservation,the smallest was 0.3%of cleaning of the environment.