Abstract:

With the development of economy and society, human and trade activities constantly increasing in Qinling Mountains, an important ecological security barrier. Alien plants have invaded and rapidly spread around this region, seriously affecting the conservation of biodiversity. However, there is a lack of comprehensive and detailed research on the present situation, harm and risks of these alien plants. It is urgent to conduct a systematic study on the invasion status of alien plants in the Qinling Mountains and assess the risk of these plants. We analyzed the distribution, habitat, diffusion and other basic information of alien plants on the north and south slopes of the middle Qinling Mountains based on the field investigation. In this paper, we constructed a risk assessment system of alien invasive plants in this area using the analytic hierarchy process (AHP) to evaluate the invasive risk of the alien plants. The results showed that 1) there were 131 alien species in the Qinling Mountains, belonging to 33 families and 87 genera, mainly concentrated in Asteraceae, Amaranthaceae, Poaceae and Fabaceae. Asteraceae had the largest number of alien plants (35 species), accounting for 26.52%; 2) the introduction period of alien plants was mainly concentrated between 50 and 150 years (54.20%). Most of them were intentionally or unintentionally introduced into China (75.57%); 3) the risk assessment system of alien invasive plants included invasive characteristics, invasive status, diffusion characteristics, and harm and impact, with a total of 13 indicators. Among the 131 alien plants, 4, 18, 29 and 80 species were extremely high-risk, high-risk, medium-risk, and low-risk plants, respectively. These results indicated that alien plants in the Qinling Mountains are diverse and have wide distribution range, with varying invasion risks. It is urgent to implement prevention and control measures on alien plants with different invasion risk levels to ensure the integrity of biodiversity and the ecological environment to the maximum extent. Enhanced control and long-term intensive monitoring are recommended for high-risk plants, while attention to potential hazards is recommended for medium-risk and low-risk plants.

Key words: Qinling Mountains, alien plants, biological invasion, invasion status, introduction pathways, risk assessment

摘要：

作为中国重要生态安全屏障的秦岭，随着经济社会的不断发展，大量人为活动穿梭其中，使得外来植物得以侵入并迅速蔓延和扩张，势必影响当地生物多样性保护，然而这些外来种的入侵现状、危害与风险等信息还缺乏全面详细的研究，为秦岭生物多样性保护埋下巨大“安全隐患”，因此亟待全面系统地研究秦岭林区外来植物的相关现状信息，并对其进行科学有效的入侵风险评估。通过野外调查秦岭中段南北坡外来植物的种类、分布现状、生境类型、扩散趋势等，采用层次分析法构建秦岭外来植物入侵风险评价体系，对该区外来植物进行风险等级划分并提出防范管控措施。结果表明：1）秦岭外来植物有131种，隶属33科87属，主要集中在菊科（Asteraceae）、苋科（Amaranthaceae）、禾本科（Poaceae）、豆科（Fabaceae），其中菊科植物数量最多（35种），占总种数的26.7%；2）秦岭外来植物传入年限主要集中在50－150 a之间（54.2%），大部分通过有意引入和无意引进带入国内（75.6%）；3）秦岭外来植物入侵风险评价体系涵盖外来植物入侵性、已入侵分布现状、扩散性和危害与影响4个方面，共设置了13个指标。131种外来植物中极高风险、高风险、中风险和低风险植物分别为4、18、29和80种。这些结果说明，秦岭外来植物种类多，分布范围较广，入侵风险不一，亟需有针对性地监控和管理不同入侵风险等级的外来种，重点监管高风险植物的蔓延扩散动态，关注中低风险植物的潜在危害，最大限度确保生物多样性和生态环境完整性。

关键词: 秦岭, 外来植物, 生物入侵, 入侵现状, 传入途径, 风险评价