紫花含笑适宜生境的保护空缺与人类干扰分析

以紫花含笑地理分布点数据为基础，结合地形和气候数据，使用最大熵（MaxEnt）模型，对紫花含笑的生境适宜度进行了评估，并基于阈值法，将紫花含笑生境分为适宜区和最适宜区，分析了紫花含笑生境适宜区和最适宜区在我国的地理分布、保护现状以及人类干扰状况，结果表明：年均降雨量对紫花含笑的分布影响最为重要，地形因子和温度因子对紫花含笑的分布影响相对较小；紫花含笑的生境最适宜区面积为13.7万km²，适宜区为27.0万km²，分布在22°~30°N，107°~120°E之间.广东、福建、广西、江西和湖南等5个省是紫花含笑生境最适宜分布区面积最广的地区；位于国家级自然保护区内的生境最适宜区和适宜区面积约占总面积的1.9%，大部分适宜生境未得到有效保护；紫花含笑生境适宜区和最适宜区内，林地是最大的土地利用类型，但是各项人类活动也占有相当大的比例.

Conservation status and human disturbance of the habitats of Michelia crassipes Law in China

This research aims to assess the habitat suitability of Michelia crassipes Law based on the species distribution data derived from specimen records and environmental variables through the approach of MaxEnt. The predicted habitat suitability was divided into suitable area and most suitable area according to the selected threshold. National reserve and land use data were used to conduct the analysis of conservation status and human disturbance of suitable habitat. The results show:Compared with topography variables and temperature variables, annual precipitation was the most important variables which influences the habitat suitability. The suitable habitat for Michelia crassipes Law was mainly located in the east area of middle subtropics, between 22 and 30degrees north latitude and between 107 and 120 degrees east longitude. The area of most suitable habitat and suitable habitat were 137000km² and 270000km². Guangdong, Guangxi, Hunan, Jiangxi and Fujian share the largest area of suitable habitat. Only 1.9% of the suitable habitats were under the protection of national reserves. Large areas of the suitable and most suitable habitats were left in a state without any protection. Woodland occupy the largest area of the suitable and most suitable habitat. However, human disturbance also occupy big area of suitable and most suitable habitat.