基于倾向得分匹配方法的中国自然保护区缓解人类活动压力评估

An assessment of the effectiveness of China’s nature reserves for mitigating anthropogenic pressures based on propensity score matching

科学地评估自然保护区缓解人类活动压力的效果,对于有效的自然保护至关重要。目前中国国家尺度下的这方面研究,仅将保护区内、外的人类活动压力进行对比,其缺陷是样本选择性偏差会导致评估结果的不合理。本文选择了倾向得分匹配(Propensity Score Matching)方法来克服保护区评价中的样本选择性偏差问题。首先耦合多源数据构建了2013年、2015年、2017年的人类活动压力指数,然后采用倾向得分匹配方法对自然保护区内、外的随机点进行匹配,使两个对比组的观测变量尽可能相似。最后通过相对有效性指标和面板模型从不同层面评估了中国680个自然保护区在2013—2017年间缓解人类活动压力的效果。研究结果表明:(1) 2013—2017年,全国86.72%的自然保护区内人类活动压力指数呈现上升趋势,其面积占保护区总面积的43.80%。(2) 69.85%的自然保护区在缓解人类活动压力方面的效果较好。其中,除了海洋海岸、野生植物、野生动物类的保护区以外,其余保护区类型都表现出较好的缓解人类活动压力的效果,且保护区级别越高,保护效果越好。(3)中国自然保护区建设在2013—2017年间能缓解22.90%的人类活动压力,且保护区缓解人类活动压力的能力存在区域性差别。本文研究结果可为中国自然保护区监测、评估和管理提供更科学的参考依据。

Assessing the effectiveness of nature reserves for mitigating anthropogenic pressures is essential for effective nature protection. The current research at national scale in China only compares anthropogenic pressures inside nature reserves to that outside, but fails to solve the problem of sample selection deviation, which will lead to bias in assessment results. In order to solve this problem, we adopted propensity score matching method to improve the accuracy of the results in the evaluation of nature reserves. The multi-source data were firstly integrated to build Anthropogenic Pressure Index in 2013, 2015, and 2017, then the propensity score matching method was applied to match the random points inside and outside the nature reserves, to make sure that the observed variables of the two comparison groups were as similar as possible. Finally, we used relative effectiveness indicator and panel model to assess the effectiveness of 680 nature reserves in China for mitigating anthropogenic pressures from 2013 to 2017 at different levels. The results show that:(1) From 2013 to 2017, 86.72% of China’s nature reserves experienced a positive trend of anthropogenic pressures, which accounted for43.80% of the total area.(2) Some 69.85% of nature reserves performed well in mitigating anthropogenic pressures. Except for marine coasts, wild plants, and wild animals, the types of nature reserves were under sound protection, and the higher the level of nature reserves, the better the protection effectiveness.(3) From 2013 to 2017, anthropogenic pressures were mitigated by 22.90% by the construction of China’s nature reserves, and there were regional differences regarding the degree of mitigation. The results can provide a more scientific reference for future monitoring, assessment and management of nature reserves in China.