生态系统服务约束关系界定及影响机制分析

以长江经济带为研究对象，选择InVEST模型对长江经济带代表性的5种生态系统服务进行评估，根据两两配对关系原理进行约束线提取，并构建生态系统服务约束关系与影响因素相互作用模型，对其作用机制进行探究.结果表明，2000~2015年长江经济带5种生态系统服务两两间共表现出矩形型，对数型，抛物线型和驼峰型4种约束类型；7种影响因素与配对的10对约束关系间均呈弱相关性；影响因子与约束关系作用关系曲线的空间变化呈现较大差异，总体为上下波动的趋势；影响因子对约束关系的贡献程度情况各异.辐射对约束关系的平均贡献率最高，达21.43%，其中对粮食供给-生境质量的贡献率最高，为33.10%；NDVI的平均贡献率最低，为7.55%，其中对粮食供给-生境质量的贡献率最低，为5.70%；各因素间相互作用、彼此制约的关系是生态系统服务约束关系变化的内在机制.

The definition of ecosystem service constraint relations and analysis of influence mechanism

With the Yangtze River Economic Belt (YREB) as the research object, the InVEST model was selected to evaluate five important ecosystem services of YREB. The constraint lines were first extracted based on the principle of pairing relationships, and then the model for interaction between ecosystem service constraint and influencing factor was established to explore the interaction mechanism. The results demonstrated that, from 2000 to 2015, the mutual two among five ecosystem services in the YREB were constrained as four types: rectangular, logarithmic, parabolic and hump, There exhibited weak correlation between the 7 influencing factors and the matched 10 pairs of restraint relationships. The relationship curves between the influence factors and the constraint relationships had significant difference in the spatial variations but generally showing a trend of upward and downward fluctuations; the contribution degree of influence factors to the constraint relationship differs case by case. Among them, the average contribution rate of radiation to the constraint relationship was the highest, reaching 21.43%, and the contribution rate to food supply-habitat quality was the highest, 33.10%; the average contribution rate of NDVI was the lowest 7.55%, and the contribution rate to food supply-habitat quality was the lowest 5.70%; the interaction and constraint relationship between various factors turned out to be the internal mechanism assigning to the change of ecosystem service constraints.