基于地理探测器的四川省大熊猫国家公园生态环境时空变化及其归因分析

Spatiotemporal variation and driving forces of ecological environment of Giant Panda National Park in Sichuan Province based on geographical detector

大熊猫(Ailuropoda melanoleuca)栖息地的生态环境状况直接决定了大熊猫种群繁衍和延续,定量评估其生态环境状况及其影响因素对国家大熊猫公园的规划和管理具有重要的科学意义和实践参考价值。本文以四川省邛崃山-大相岭片区大熊猫国家公园为研究对象,基于遥感生态指数(remote sensing ecological index,RSEI),分析了公园建立前(2015年)后(2021年)生态环境状况的时空变化,并利用地理探测器定量分析了自然及社会驱动因子对公园生态环境状况的贡献。结果发现:(1)公园生态环境状况为“优”和“良”的等级比例较高(~70%),且多分布于核心保护区,表明区域生态环境状况整体较好。(2)与2015年相比,2021年“优”、“差”等级的RSEI比例均有所降低,主要转移为“良”、“中”等级。区域生态状况整体变化不大,但存在较明显的空间差异性。其中,海拔较高的西北区域及人类干扰较多的一般控制区的生态环境状况波动较大。(3)自然因素是导致本区域生态环境状况变化的主要驱动因素,其次为人为因素。各自然因子的贡献大小排序为:归一化植被指数(NDVI,0.87)>干度指数(0.58)>湿度因子(0.54)>海拔(0.38)>土地利用覆被类型(0.37)>年均温(0.36),其中NDVI与其他因子存在较强的交互作用。生态环境最适宜的区域应当给予重点关注,如NDVI值在0.875~1、海拔1720~2150 m、年均温14.1~16.3℃的区域,以及针叶林覆盖的区域。本研究结果将为我国大熊猫生境质量的评价和保护提供重要的参考依据。

The ecological environment of giant panda(Ailuropoda melanoleuca)habitat directly determines the reproduction and continuation of giant panda population.The quantitative evaluation of giant panda ecological environment and its influencing factors is of great scientific and application significance for the planning and management of Giant Panda National Park(GPNP)in the Qionglai-Daxiangling Mountain region of Sichuan Province.Based on the remote sensing ecological index(RSEI),we analyzed ecological environment status and its spatiotemporal variation of the study area before(2015)and after(2021)establishment of GPNP.The contribution of natural and social driving factors to the ecological environment status of the park was quantitatively analyzed by using the geographical detector.The results showed that:(1)The proportion of“excellent”and“good”grades of ecological environment status in the park was high(~70%in total),and most of them were distributed in the core zone of the GPNP.The overall ecological environment status of the region was good.(2)Compared with 2015,the RSEI levels of“excellent”and“poor”in 2021 were reduced and transferred to the other levels.The ecological quality of the region changed slightly as a whole,with obvious regional differences.The ecological environment status fluctuated greatly in the northwest region with higher elevation and the general control zone with more human activities in the southwest of the study area.(3)Natural factors were the main driving forces leading to the change of ecological environment status,followed by human factors.The order of contribution of the top six factors was:the normalized vegetation index(NDVI,0.87)>dryness index(0.58)>wetness(0.54)>altitude(0.38)>land-cover type(0.37)>annual average temperature(0.36),with strong interactions between NDVI and the other factors.More attention should be paid to the most suitable areas,such as those of NDVI value of 0.875-1,altitude of 1720-2150 m,annual average temperature of 14.1-16.3℃,and those covered by coniferous forests.This study can provide an important reference for the evaluation and protection of giant panda habitat quality in the GPNP.