关键词: 三江源, 农牧民响应, 政府主导, 山江湖, 外部不经济性, 生态建设工程

Abstract: This paper selected two typical ecological construction projects as the object, i.e., Mountain-River-Lake of Jiangxi and Three-River Headwaters of Qinghai, to identify the negative external effect induced possibly by farmers and herdsmen' participation under the different ecological construction periods, using participatory rural appraisal method from farmers and herdsmen cognitive perspective. These results showed: 1) The direct negative externality resulted from farmers' behavior was easily adjusted in Mountain-River-Lake area, while that induced by herdsmen' participation was difficult to control and regulate in Three-River Headwaters area. 2) The potential negative externality of farmers' behavior was mainly driven by exogenous variable in Mountain-River-Lake area, e.g., migrant workers resulted in the increase of wild boar and forest fire, and the mountain trees suffered massive damage due to an increase of rats induced by snake hunting. Although herd structure and adult female ratio were also affected by grassland degradation in Three-River Headwaters area, the relationship between them and grassland degradation presented stronger endogenous. 3) Farmers could understand more clearly strong probability negative externality resulted from farmers' management behavior intervention, and evaluate it scientifically and qualitatively in Mountain-River-Lake area. Strong probability negative externality caused by herdsmen' engagement in secondary and tertiary industries could become income gap in Three-River Headwaters area, via to the differences of herdsmen' culture, ability, customs, and so on. Under such environment, it was easy to return herd for herdsmen. 4) Small probability negative externality induced by farmers' behavior adjustment in Mountain-River-Lake area was determined by forest which was a disadvantaged industry. Namely, it was driven by climate change, and possessed irresistible features. But, to some extent, the disaster losses caused by it could be relatively reduced, if appropriate management behavior was applied in the early stage. In Three-River Headwaters area, it was brought by herdsmen' behavior adjustment and was affected by the external economic environment or introduced industrial status. And, to a certain degree, it could be regulated. The policy implication of this paper aimed at identifying the references of farmers and herdsmen' adaptability behavior adjustment, in order to reduce or mitigate negative external effect, in the process of two major ecological construction projects.

Key words: negative external effect, government leading, farmers and herdsmen’response, ecological construction projects, Mountain-River-Lake , Three-River Headwaters