亚洲象生境长时序变化及其对人象冲突的影响——基于融合MaxEnt与HSI模型的生境适宜性评价方法

生境变化直接关系到物种种群维持与人类安全，揭示其长期变化规律及其对人类的影响，可为物种保护与生境恢复提供科学支撑。但因受物种活动点数据获取与位置精度的局限，鲜见濒危、危险物种的长时序生境变化研究。以人象冲突频发的西双版纳勐海—普洱澜沧地区亚洲象种群(勐海—澜沧象群)活动区为例，提出融合MaxEnt与HSI模型的亚洲象长时序生境适宜性评价方法，即基于荟萃分析筛选出的15个亚洲象生境评价因子，结合近期有限的物种活动点监测数据，利用MaxEnt得到生境评价因子的贡献率，再运用HSI模型计算生境适宜性指数；利用该方法制作出研究区1988—2020年逐年时序的亚洲象生境适宜性图，以分析亚洲象生境的时空变化，将其与亚洲象肇事数据结合，进而分析人象冲突与生境变化的关联。结果表明：(1)基于物种生境偏好不变的前提，融合MaxEnt模型与HSI模型的生境适宜性评价方法可应用于物种的长时序生境评价，且基于亚洲象活动点数据从动物对生境利用的生态学视角定量获取亚洲象对各生境评价因子的偏好程度，使生境评价结果具有良好的生态可解释性；(2)目前亚洲象适宜生境面积占研究区面积三分之一(4039.76 km^...

Long time series changes of Asian elephant habitat and impacts on human-elephant conflict: based on habitat suitability evaluation method by combining MaxEnt and HSI models

Habitat change features prominently in maintenance of species population and human security. Understanding the roles of historical habitat change in species protection are crucial for habitat management or restoration and evaluating effectiveness of species conservation. However, due to lack of spatially unbiased species occurrence data, mapping long-term changes of the endangered species'' habitats remains unsolved. In this study, taking the range of Menghai-Lancang Asian elephant herd with frequent human-elephant conflicts as an example, a new habitat suitability evaluation method for mapping long-term changes of habitat was proposed. A total of 15 habitat evaluation factors were selected by meta-analysis. Based on the contribution rate of each evaluation factor to habitat quality derived from the MaxEnt model driven by Asian elephant occurrence point, we combined a habitat suitability index (HSI) model and the MaxEnt-derived contribution rates of habitat evaluation factors to evaluate the Asian elephant habitat suitability from 1988 to 2020. Based on the resultant long time-series habitat suitability of Asian elephants, we analyzed spatio-temporal dynamics of Asian elephant habitat and the relations between human-elephant conflicts and habitat landscape changes. Results show that: (1) under the premise of unchanged habitat preferences of species in the study period, the MaxEnt model and the HSI model could be integrated for the long-term habitat evaluation with the inherent relations between the habitat use of species and the environmental factors; (2) The area of existing suitable habitat accounted for one third of the study area (4039.76 km²), which were mainly distributed along the main streams of rivers (such as the Lancang River, Nanlang River and Nanlan River), and the habitat suitability decreased with the distance apart from the river; (3) The highly suitable habitat for Asian elephants decreased by 4.7% (568.48 km²) from 1988 to 2020, in which about 3% (362.89 km²) were lost from 2000 to 2013; the connectivity of habitat patches decreased significantly, especially for the optimum habitat patches; conversely, the number of habitat patches increased by 10.8%, indicating that habitat landscape fragmentation worsened; (4) The area of the degraded habitat accounted for 9.11% (1094.21 km²) in the study area from 1988 to 2020, and human elephant conflicts mainly occurred in the habitat degraded areas; moreover, habitat degradation and habitat fragmentation caused by human activities and modifications of natural environment were the main factors for the occurrences of human-elephant conflict accidents. Therefore, rehabilitating the connectivity of suitable habitat patches are urgently needed for thriving the Asian elephant population, mitigating human-elephant conflicts and boosting ecological civilization construction.