退耕还林可持续性研究 英文标题:Research on the Viability of the Grain for Green Project

退耕还林(草)工程是中国政府对1997年黄河流域的严重干旱、1998年长江流域的毁灭性洪灾等一系列环境灾难和环境退化的深刻反思后的积极响应。国家以财政补贴的方式，激励农民停止耕种那些水土流失严重，沙化、盐碱化、石漠化严重和生态地位重要、粮食产量低而不稳定的耕地，并有计划、有步骤地还林还草，恢复植被。从1999年工程试点以来，退耕还林的可持续性一直是国内外学者关注的焦点。虽然现有文献对工程执行问题、生态影响及效果、社会经济影响、生态补偿问题、后续产业发展问题等方面进行了广泛研究并取得大量成果，但有关工程的长期可持续性并未达成一致的结论。纵观已有研究成果，至少以下几个关键问题并未引起足够关注：退耕还林的环境价值(包括其非使用价值)及其收益-成本效率有多大?作为农户收益改善的构成部分，退耕还林对土地生产力的提高效果有多大?退耕还林对农民的非农就业时间配置是否有显著影响?现有的补贴标准是否合理、合理的生态补偿标准是多少?本研究基于重庆万州区的实地微观调研数据，从定量评价政策本身的可持续性和政策实施的可持续性两个层面就这些问题进行了深入探讨。主要研究内容及结论如下：关于退耕还林政策本身的可持续性，本研究主要利用样本区的农户和城市家庭的选择实验调查数据，从环境受益者的支付意愿(WTP)角度定量评估了退耕还林的环境价值及政策的收益-成本效率。研究发现，98.04%的农户和80%的城市家庭愿意以“环保捐赠”的方式维护退耕还林的生态环境改善功能；基于受益者WTP评价的环境总价值高达327048137.61元／年；按照工程第一轮和第二轮补贴标准、并结合工程实施成本计算，样本区退耕还林的收益-成本比分别为2.72：1和4.96：1。由于工程显著地改善了生态环境并取得较好的生态绩效，继续保持退耕还林是未来可取的政策选择。政策本身是可持续的。关于退耕还林政策实施的可持续性，本研究利用样本农户的调查数据，主要从农户收益改善角度对以下三个方面做出定量分析和评价：第一，退耕还林生态功能对土地生产力的改善效果。研究发现，在没有重大农业技术进步和除退耕还林政策以外的制度创新这一特定的样本背景下，保持其他因素不变，退耕还林(通过其生态改善功能)使玉米和小麦的地块单产分别提高了12.7%和20.9%。研究还发现，样本区的土地生产力还显著地受到地块大小(即面积)、资本投入、土地质量、农户决策者的年龄、农技培训等因素影响。第二，退耕还林的非农就业调整效果。研究发现，工程参与和参与强度虽然对农民的非农就业时间配置具有积极作用，但总体效果不显著；农民非农就业时间的普遍增加只是一种时间趋势，并非退耕还林政策的作用。尽管如此，退耕还林还是显著地促进了家里有老人、劳动力在4人以上和人均耕地面积低于1亩的农民的非农就业时间的增加，也显著地增加了女性农民、具有干部和党员身份的农民的非农就业时间。研究还发现，显著地影响农民的非农就业时间配置的因素是其家庭特征和个人特征，其中，家庭特征包括老人数和劳动力数，个人特征包括性别、年龄、教育程度、健康状况和退耕前非农就业与否。第三，退耕还林生态补偿标准测算及现有补贴水平的合理性。成本流的分析发现，农户退耕还林的机会成本为7760.35元/hm2·年，全部成本(包括机会成本和环境服务提供成本)为8985.25元/hm2·年；保护拍卖的实验模拟显示，确保参与农户不复耕(当前参与率不变)的农户接受意愿(WTA)为4500元/hm2·年，保持现有退耕面积不变的农户WTA在3450-4500元/hm2·年之间；选择实验的测算结果表明，退耕地的生态价值贡献为10639.77元/hm2·年。基于退耕还林成本、农户WTA和退耕还林生态价值贡献的不同补偿标准测算结果，退耕还林的现有补贴标准(1875元/hm2.年)对农户补偿不足。根据以上三个方面的研究结论可以判断，虽然土地生产力的提高显著地得益于退耕还林的生态改善，但其效果并不足以弥补退耕农户的收益损失；退耕还林也并不具有普遍的非农就业调整效果；在工程只有较低的经济绩效和原来补偿水平(3450元/hm2·年)不足的情况下，2007年补贴水平的下降(降低为1875元/hm2·年)，导致了退耕农户成为退耕还林中的净损失主体。因此，退耕还林政策实施的可持续性堪忧。从工程设计来看，农户持续参与是退耕还林政策长期可持续的前提，其关键又在于参与农户的收益改善。结合上述研究发现，本文最后从进一步提高未退耕地的生产力、促进农民非农就业和实施公平、合理的生态补偿等途径提出了一些具体的配套措施和政策建议。

The Grain for Green Project (GGP) is a proactive response by the Chinese government following profound reflections on a series of environmental disasters and degradation, such as the severe drought in the Yellow River basin in 1997 and the catastrophic floods in the Yangtze River basin in 1998. The state uses financial subsidies to incentivize farmers to cease cultivating farmland that suffers from severe soil erosion, desertification, salinization, and rocky desertification, as well as farmland with important ecological status but low and unstable grain yields, and to restore vegetation through planned and phased afforestation and grassland restoration.
Since the project’s pilot launch in 1999, the sustainability of the Grain for Green Project has been a focal concern for scholars both domestically and internationally. While existing literature has conducted extensive research and yielded abundant findings on issues such as project implementation, ecological impacts and effects, socio-economic impacts, ecological compensation, and subsequent industrial development, no consensus has been reached on the long-term sustainability of the project.
Reviewing existing research outcomes, at least the following key issues have not received sufficient attention: What is the environmental value (including its non-use value) and benefit-cost efficiency of the Grain for Green Project? As a component of farmers’ income improvement, to what extent does the GGP enhance land productivity? Does the GGP have a significant impact on farmers’ off-farm employment time allocation? Are the current subsidy standards reasonable, and what is a reasonable ecological compensation standard?
Based on field micro-survey data from Wanzhou District, Chongqing, this study conducts an in-depth exploration of these issues from two dimensions: quantitatively evaluating the sustainability of the policy itself and the sustainability of policy implementation.
Regarding the sustainability of the GGP policy itself, this study mainly uses choice experiment survey data from rural households and urban households in the sample area to quantitatively assess the environmental value of the GGP and the benefit-cost efficiency of the policy from the perspective of the willingness to pay (WTP) of environmental beneficiaries. The study finds that 98.04% of rural households and 80% of urban households are willing to maintain the ecological improvement functions of the GGP through "environmental protection donations"; the total environmental value evaluated based on beneficiaries’ WTP reaches as high as 327,048,137.61 yuan per year; calculated according to the first and second round subsidy standards of the project and combined with project implementation costs, the benefit-cost ratios of the GGP in the sample area are 2.72:1 and 4.96:1, respectively. Since the project has significantly improved the ecological environment and achieved good ecological performance, continuing the GGP is a desirable policy option for the future. The policy itself is sustainable.
Regarding the sustainability of GGP policy implementation, this study uses survey data from sample rural households to conduct quantitative analysis and evaluation on the following three aspects mainly from the perspective of farmers’ income improvement:
First, the improvement effect of the GGP’s ecological functions on land productivity. The study finds that under the specific sample context without major agricultural technological progress and institutional innovations other than the GGP policy, keeping other factors unchanged, the GGP (through its ecological improvement functions) increases the plot yields of corn and wheat by 12.7% and 20.9%, respectively. The study also finds that land productivity in the sample area is also significantly affected by factors such as plot size, capital investment, land quality, age of the household decision-maker, and agricultural technology training.
Second, the off-farm employment adjustment effect of the GGP. The study finds that although project participation and participation intensity have a positive effect on farmers’ off-farm employment time allocation, the overall effect is not significant; the general increase in farmers’ off-farm employment time is merely a temporal trend, not the effect of the GGP policy. Nevertheless, the GGP significantly promotes an increase in off-farm employment time for farmers who have elderly family members, have more than 4 laborers, and have a per capita arable land area of less than 1 mu, and also significantly increases the off-farm employment time of female farmers and farmers with cadre or Party member identities. The study also finds that the factors that significantly affect farmers’ off-farm employment time allocation are their household characteristics and personal characteristics, where household characteristics include the number of elderly people and the number of laborers, and personal characteristics include gender, age, education level, health status, and whether they had off-farm employment before the GGP.
Third, the calculation of ecological compensation standards for the GGP and the rationality of existing subsidy levels. Cost flow analysis finds that the opportunity cost of farmers participating in the GGP is 7760.35 yuan/hm²·year, and the total cost (including opportunity cost and environmental service provision cost) is 8985.25 yuan/hm²·year; experimental simulation of protected auctions shows that the willingness to accept (WTA) of participating farmers to ensure no re-cultivation (with the current participation rate unchanged) is 4500 yuan/hm²·year, and the WTA of farmers maintaining the existing afforested area is between 3450 and 4500 yuan/hm²·year; the calculation results from choice experiments show that the ecological value contribution of retired farmland is 10639.77 yuan/hm²·year. Based on different compensation standard calculation results from GGP costs, farmers’ WTA, and the ecological value contribution of the GGP, the current subsidy standard of the GGP (1875 yuan/hm²·year) provides insufficient compensation to farmers.
Judging from the research conclusions of the above three aspects, although the improvement of land productivity significantly benefits from the ecological improvement of the GGP, its effect is not sufficient to make up for the income loss of farmers participating in the GGP; the GGP also does not have a universal off-farm employment adjustment effect; under the circumstances that the project has only low economic performance and the original compensation level (3450 yuan/hm²·year) was insufficient, the reduction of the subsidy level in 2007 (to 1875 yuan/hm²·year) caused participating farmers to become net losers in the GGP. Therefore, the sustainability of GGP policy implementation is a cause for concern.
From the perspective of project design, the continuous participation of farmers is the prerequisite for the long-term sustainability of the GGP policy, and the key lies in improving the income of participating farmers. Combining the above research findings, this paper finally puts forward some specific supporting measures and policy recommendations from the aspects of further improving the productivity of non-retired farmland, promoting farmers’ off-farm employment, and implementing fair and reasonable ecological compensation.

搜集汇总

背景与挑战

背景概述

该数据集聚焦于中国退耕还林工程的可持续性研究，基于重庆万州区的实地微观调研数据，定量评估了政策的环境价值、收益-成本效率、土地生产力改善效果、非农就业影响及生态补偿标准。研究发现政策本身具有可持续性（收益-成本比达2.72:1至4.96:1），但实施可持续性堪忧，因补贴标准不足导致农户收益损失。数据集适用于植物学、环境政策和社会经济影响分析领域。