Assessing Effectiveness Of Sloping Land Conversion Program

Effectiveness is an important criterion for improving the feasibility and sustainability of payment for ecosystem services(PES)program,including environment-effectiveness and cost-effectiveness.However,as the largest PES program in China,the effectiveness of the Sloping land conversion program(SLCP)is difficult to be reflected using the investigation of farmer levels due to the small and scattered cultivated land.The detection of Land use/Land cover change(LUCC)is the research core of global change and sustainable development accompanied with the GIS and remote sensing technology.It can evaluate the improvement of ecological or environmental quality by measuring the LUCC ecosystem services and vegetation changes in a specific period at the landscape level.Many used the comparative analysis method to describe the spatiotemporal differences or changes of ecological or environmental quality after the SLCP`s implementation in the natural disciplines.However,there is a lack of systematic and quantitative study on the SLCP`s effectiveness,especially the cost-effectiveness.In addition,we can also improve in the impact scopes of SLCP,forest and grassland spatial allocation,regional investment selection,forest investment structure and trading mode.We assessed the effectiveness of SLCP in Shaanxi province,China,including the environment-effectiveness and cost-effectiveness using the advantages of economics,ecology,geography and other interdisciplinary.For the environment-effectiveness,firstly,we used the GIS and remote sensing technology to detect the LUCC and ecosystem service value after the SLCP`s implementation.And then,we summarized the general law and motivation of land use transition were,and designed the identification model of ecological sensitivity factor to investigate the sensitivity of the SLCP to the changes of ecological or environmental quality.Furthermore,marginal contribution of the SLCP to vegetation was estimated by applying the treatment effect model(TEM),and then we constructed the comparative advantage index to assess the effectiveness of forest and grassland spatial allocation.For cost-effectiveness,first,the panel fixed effect model with dummy variables was used to estimate the financial investment efficiency of Shaanxi Province at different spatial scales(the river basin,natural geography zone and county level)for identifying the priority investment zones with high return rate.Second,we also calculated the marginal contribution and spatial heterogeneity of ecological and economic forests investments to vegetation restoration,respectively and detected their substitution effect.Finally,our study analyzed the advantages and feasibility of cross-regional horizontal trading mode of ecological conversion,and constructed the pricing theoretical model of ecological conversion under the goal of sustainability of cultivated land for promoting SLCP`s effectiveness.The main conclusions are as follows.Land use transition showed rational motivation and followed the general economic law in Shaanxi province.When suffering economic stimulation,cultivated land would be transferred to urban and rural construction land characterized by higher economic value.While promoting the SLCP,cultivated land would be transferred to ecological land such as forest or grassland characterized by low conversion cost.The process of land use transition indicated the economic flow of "unused land ? grassland ? cultivated land ? urban and rural construction land" in Shaanxi Province from 1990～2000.However,it showed the ecological flow of "cultivated land ? forest or grassland" and "cultivated land ? urban and rural construction land" from 2000～2015.It generated expensive opportunity cost of transferring urban and rural construction out due to its higher economic value than the income of urban and rural construction land.Whether there were external economic opportunities or the intervention of ecological environment policy,it was difficult for urban and rural construction land to transfer to other land types.The SLCP in Shaanxi Province showed environment-effectiveness,but it played a major role in the Northern Shaanxi plateau,and there is a serious spatial mismatch of forest and grassland.The ecosystem service value from 2000～2015 increased by CNY 2.7096 billion,and it was 3.5 times of that from 1990 to 2000 in Shaanxi province,but the rate of "capital value-ecosystem services value" was only about 10.28%.Moreover,the average NDVI was0.831 in Shaanxi province in 2015,an increase of 15.097% compared with that in 2000.The average increasing rate of NDVI in the Yellow River Basin was about 3.042 times that in the Yangtze River Basin,and the gravity center of NDVI moved to the northeast as a whole which indicated the SLCP`s effect in the North was better than that in the South.Nevertheless,vegetation began to degenerate in the later stage of the project due to the reduction of afforestation scale and reclamation and other reasons.We could use the ecological sensitivity factor identification model to detect the more effective zones of SLCP.From 1990～2000,Shaanxi Province was dominated by destructive factors,while it was dominated by ecological protection factors from 2000～2015.In particular,the most sensitive factors in Northern Shaanxi plateau were “cultivated land ? forest land” and “cultivated land ? grassland” and it indicated that the SLCP had played a role in ecological protection in Northern Shaanxi Plateau since 2000.Under the counterfactual framework,the average NDVI of the SLCP areas was 0.0426 higher than that of the non-SLCP areas,and the marginal contribution of planting forests was 1.8717 times of that of seeding grass.The relative advantage index could allocate the forest and grassland in different spaces effectively.The areas being suitable for planting forests were mainly distributed in the south of Northern Shaanxi plateau,especially in Huanglong county,Huangling county,Fu county and Yichuan county,while other areas were suitable for seeding grass.It was worth noting that there was a serious spatial mismatch between forest and grassland in Wuqi county,Ansai county,Zhidan county,Zichang county and other key project areas.These areas should choose to seeding grass instead of planting forests.The cost-effectiveness of SLCP could be improved.As for regional investment selection,the project of returning farmland to forest in Shaanxi Province is more cost-effective in the North(Yellow River Basin,Northern Shaanxi plateau and Guanzhong plain)compared with the South(Southern Shaanxi mountainous),however,the financial investment efficiency was worse in Wuqi county,Ansai county and Zhidan county in the North.As for the forest investment selection,ecological forest investments were more cost-effective than economic forest investments for promoting vegetation restoration.In addition,ecological forest investments in the North(Yellow River basin or Northern Shaanxi plateau,Guanzhong Plain)were more cost-effective than in the North(Yangtze River basin or Southern Shaanxi mountainous).Furthermore,there was obvious substitution effect in the two kinds of tree investments,and it was no doubt that it would aggravate the low efficiency of the financial investments of SLCP.And when we only invested in ecological forests,the costeffectiveness of the SLCP would peak.As for transaction mode,it was superior and feasible to change the from vertical transaction mode to cross-regional horizontal transaction mode of ecological conversion in Shaanxi province.Additionally,the ecological payment areas of Shaanxi Province were mainly distributed in Guanzhong plain,Hanzhong basins and Ankang basins,which were similar to the distribution pattern of cultivated land,and consistent with the distribution pattern of a higher opportunity cost areas of sloping land conversion.And ecological acceptance areas of cultivated land were basically consistent with the distribution pattern of plateaus,mountains and hills,and generally located in the region with a lower opportunity cost of sloping land conversion.In the new round of the project,the government should improve the incentive scheme of SLCP,enhance the regional targeting of the SLCP and guide participants to choose the appropriate vegetation types based on their effectiveness.Moreover,Shaanxi province should invest in the North(Northern Shaanxi plateau or the Yellow River basin)if using the current payment system,while the South(Southern Shaanxi mountainous)should adhere to the ecological restoration strategy of “natural restoration as the main and artificial restoration as the auxiliary”.Or we should use the "performance payment method" and reduce the payment price or investment scales.And it should be strengthened to assess and supervise the financial performances of SLCP in some key SLCP areas.The government should be cautious about the policy changes of the new round of SLCP to prevent the possibility of ecological deterioration.It was critical to increase the ecological forest subsidies instead of economic one for encouraging more farmers to plant ecological forests.Finally,the government should gradually change the incentive system of the SLCP,explore and establish cross-regional horizontal trading mode of SLCP.And it would realize regional environment self-government based on improving the cost effectiveness of the SLCP.