中国の「退耕還林」政策が農家経済へ及ぼす影響

陜西省・内モンゴル自治区の事例

抄録

This study explores impacts of the conservation set-aside program in China known as "Grain for Green" on the structure of agricultural production and the productivity of individual farms. Although this program is one of the largest soil conservation programs related to agriculture in developing countries, so far few studies have tried to make an economic evaluation of the impacts of the program, especially an econometric analysis.
Surveys for 332 households were conducted in the southern part, the central part and the northern part on the Loess Plateau in Shanxi Province, and the southern part of the Mongolian Plateau in Inner Mongolia Autonomous Region. Soil degradation is severe in these regions, especially in the central region of Shanxi.
Estimation of changes in farm incomes after the program shows that many farm households have stabilized their incomes by shifting from grain production to livestock production and by shifting their surplus labor to off-farm employment. While grain production has decreased rapidly since the program implementation, the number of small animals and amount of feed production have increased.
Changes in the technical efficiencies of individual farms are estimated by stochastic frontier production function models. The efficiencies are likely to decline especially in unfavorable areas in terms of natural conditions. The efficiencies tend to decline more for farms with a greater proportion of farmland reserve. Thus, the government should implement supplementary programs to encourage smooth transition after the program and maintain their productivity. This study confirms the importance of off-farm employment; however, the employment opportunity in urban areas is insecure. Public support to maintain the farm incomes is necessary especially for elderly households with little employment opportunity.