我国国家级自然保护区主要外来入侵植物分布格局及成因

自然保护区在生物多样性保护中起着关键作用，然而也面临外来物种入侵等诸多压力。基于72个已调查国家级自然保护区外来入侵植物数据，重点分析生态环境部发布的四批外来入侵物种名单中已有分布的35种外来入侵植物分布格局及其影响因素。研究发现72个国家级自然保护区平均记录有（7.78±0.47）种外来入侵植物，MaxEnt模型预测结果表明98.69%的国家级自然保护区面临外来植物入侵风险。低纬度地区（8.07±0.73）和中纬度地区（9.64±0.56）国家级自然保护区外来入侵植物数量显著高于高纬度地区（4.53±0.88），且不同类型国家级自然保护区外来入侵植物差异不显著。温度和降雨量是影响外来入侵植物在自然保护区分布的关键因素，且影响不同生活型外来入侵植物分布格局的关键因素不同：温度对一年生草本、藤本和灌木的分布解释量极为显著，保护区建立时间、温度、降雨量和海拔共同影响多年生草本植物在国家级自然保护区的分布。研究结果表明国家级自然保护区外来入侵植物调查与监测还存在很大的空白，未来需要进一步加强自然保护区外来入侵植物研究，并提升外来入侵植物的监管能力。

The distribution pattern and determinant factors of the main invasive alien plants in national nature reserves in China

Nature reserves play a key role in biodiversity conservation. However, they confront numerous pressures including the invasion of alien species. The understanding of distribution pattern of invasive alien species in Nature reserves has been limited by inadequacy of distribution data. Here, we compiled distribution data of 72 national nature reserves in China for 35 invasive alien plants (IAPs), which issued by Ministry of Ecology and Environmental of the People''s Republic of China. The distribution pattern and potential distribution pattern of 35 IAPs were explored, then related the species patterns with environmental and human activity factors. The results indicated that:1) 7.78±0.47 IAPs were recorded in 72 national nature reserves, moreover, 98.69% of national nature reserves in China all were faced with the invasion of IAPs based on prediction of MaxEnt model. 2) The largest number of IAPs was observed in national nature reserves located in low latitude region (8.07±0.73) and mid-latitude region (9.64±0.56), which distinguished more than those in high latitude regions. No difference of IAPs richness was found among the types of national nature reserves. 3) Analysis of CCA (canonical correspondence analysis) showed that temperature and precipitation jointly dominated spatial patterns of IAPs in national nature reserves in China, whereas, human activities such as length of the road and population density in natural reserves showed little effect. Moreover, the main factors varied among different life forms of IAPs:temperature explained most of distribution of annual IAPs, vine and shrubs. On the other hand, temperature, precipitation, altitude and build time of protected areas were all related with the distribution of perennial IAPs. We concluded that a lack of investigation and monitoring data of IAPS limited the understanding the invasiveness of IAPs in nature reserves. In the future, in order to reveal the underlying invasion mechanism of IAPs and improve the effectiveness of management, more studies should be conducted in national nature reserves.