深圳市入侵植物区系与风险分布

外来植物入侵现象随着城市化的推进在各地愈演愈烈,严重影响城市的生态系统稳定和社会经济发展。在深圳陆域优势植被普查的基础上开展,对深圳全市的入侵植物分布、来源、入侵途径、风险等进行调查分析,为深圳的入侵植物防治提供技术支撑。基础数据采用高分辨率遥感影像与地面实地观察结合的方法普查得到;并通过文献分析法对植物种类基础数据按研究要求进行筛选、提取、分析;创新性的引入斑块入侵风险计算方法和入侵植物种群风险计算方法,经计算得出深圳市范围内的入侵植物风险分布现状与高风险入侵植物种群。结果表明：(1)参照《中国外来入侵植物名录》标准,深圳市陆域群落优势植物共有入侵植物63科200属258种,且以豆科、菊科、禾本科植物为主;其中36种为林业部门、生态环境部门、农业农村部和海关明确的官方认定且需要严格管控的入侵物种;(2)单种科和少种科占比较高,共占比87.3%,大型科虽然占比仅4.8%,却包含了共计106种,占入侵植物总种数41.1%;单种属在深圳入侵植物区系中占绝对优势,占比83.5%,远高于其他类型之和;中型属中,属种比为1∶6;(3)热带区系属性非常明显,热带分布科共计35科,占总科数的92.1...

Study on the flora and risk distribution of dominant invasive plants in Shenzhen

The phenomenon of invasive alien plants is increasing with urbanization in various parts of the world, seriously affecting the stability of urban ecosystems and socio-economic development. This study was carried out on the basis of a census of the dominant vegetation in the terrestrial areas of Shenzhen, to investigate and analyse the distribution, sources, invasion pathways and risks of invasive plants in the city, and to provide technical support for the control of invasive plants in Shenzhen. The basic data was obtained by the method of combining high-resolution remote sensing images and ground field observations; and the basic data of plant species were screened, extracted and analyzed according to the research requirements through the literature analysis method; the patch invasion risk calculation model and invasive plant populations risk calculation model were introduced creatively, to calculate the risk distribution of invasive plants and high-risk invasive plants species in Shenzhen. The results showed that:(1) according to the standard of "Chinese Alien Invasive Plants List", there were 258 species of invasive plants from 200 genera, 63 families in Shenzhen, and Leguminosae, Asteraceae and Poaceae were dominant; 36 of these plants were officially recognized by the Forestry, Environmental, Agriculture & Rural Affairs and Customs authorities as invasive species that require strict control. (2) Single-species families and few-species families accounted for a relatively high proportion with 87.30%. The gigantic-species families, although accounting for only 4.8% of the total number of families, contained a total of 106 species, accounting for 41.1% of the total number of invasive plant species. The single-species genus was overwhelmingly dominant at the genus level of invasive plants in Shenzhen, accounting for 83.5% of the total, much higher than the sum of the other types. Among the medium-species genera, the ratio of genera to species is 1:6. (3) The characteristics of tropical flora are very obvious. Tropical distribution families contained 35 families, accounting for 92.11% of the total families. The tropical distribution genera contained 131 genera, accounting for up to 75.72% of the total genera. (4) The invasive plants were mainly plant species native to Asia, accounting for 42.38%. Invasive plants native to South and North America also occupied a certain advantage, accounting for 25.17% and 15.89%, respectively. (5) According to the analysis of the risk of invasive species and community patches, the high risk areas of invasive plants in Shenzhen were mainly distributed in suburban or near-natural areas where human activities are low, management and maintenance are weak, and vegetation is nearly naturalized. Finally, this paper analyses the invasion pathways of eight plants with high invasion risk values and gives recommendations for the control of them.