森林转型的微观机制——以重庆市山区为例

20世纪80年代以来,我国进入森林转型阶段。系统认识森林转型的微观机制,有利于提出针对性的促进森林面积增长的措施,而已有研究未做深入分析。利用重庆市“两翼”地区的1 015份农户调查数据,论文从农户尺度分析了森林转型的微观机制及其主要影响因素。结果显示：在农户尺度上,森林转型的微观机制有薪柴替代、耕地撂荒、牲畜养殖数量减少及林果种植。农业劳动力向非农就业转移能够加快薪柴替代、林果业发展,同时也能造成耕地撂荒、牲畜养殖数量减少。此外,提高煤炭等替代能源的可获得性及加快政府沼气政策的实施和普及能加快薪柴替代;耕作半径、劣质地及野猪破坏会造成耕地撂荒,而地质灾害隐患和缺少灌溉及其他农户耕地撂荒行为等也对耕地撂荒具有一定影响;地方鼓励政策会加快林果业发展。最后,提出了加快森林植被恢复的建议。

The Micro-mechanism of Forest Transition:A Case Study in the Mountainous Areas of Chongqing

Since the 1980s, China has entered a forest transition phase, which has brought us more ecological environment services. However, it still lacks a systematic understanding of the micro-mechanisms of the forest transition on household scale, which has restricted making targeted measures for restoration of forest vegetation. Based on a field survey of 1 015 households in the “two wings” region of Chongqing Municipality, using tools of participatory rural appraisal (PRA), this paper systematically analyzes the micro-mechanisms of forest transition and their influencing factors. The results show that: 1) The micro-mechanisms of forest transition include firewood substitution, cultivated land abandonment, decrease in numbers of livestock breeding and fruit planting. In terms of firewood substitution, firewood consumption per capita and the proportion of firewood consumption decreased by 354.31 kgce and 3.46% from 2003 to 2011, respectively. For cultivated land abandonment, the area of cultivated land abandonment tended to increase since the 1980s and reached the peak between 2008 and 2011. For livestock breeding, nearly 80% of investigated rural households reduced the number of livestock by 2011. As to fruit planting, although it was ever an important factor of forest transition in other regions of the world, the total area of fruit planted by the investigated households is only 9.85 hm². 2) As the underlying cause, off-farm employment is not only in favor of firewood substitution and fruit planting, but also the reason of cultivated land abandonment and decrease in numbers of livestock breeding. In addition, the four micro-mechanisms of forest transition are also affected by other factors. For firewood, improving the availability of alternative energy (e.g. coal, liquefied gas), and speeding up the implementation of biogas policy can speed up firewood substitution. For abandonment, property of cultivated land (e.g. radius of farming, land quality), and invasion of wild boar can result in cultivated land abandonment. Meanwhile, disaster risk, lack of irrigation, and abandonment behavior of other farmers also have a litter impact on cultivated land abandonment. For fruit industry, the government encouraging policies can accelerate the development of fruit industry. The results perfectly reveal the development of four micro-mechanisms of forest transition in mountainous areas of Chongqing city and their influencing factors, which provides a scientific basis for policy-making to coordinate the contradiction between forest restoration and food safety.