中国东部10个海岛植被近自然度评价

植被近自然度评价是森林近自然恢复的重要理论基础。海岛因特殊的生物地理环境，其植被结构和功能有别于陆地植被，当前还未有从植物生理生态角度，联合植物功能性状的海岛植被近自然度评价指标体系。基于中国东部10个典型海岛的74个植物群落，以植被信息、土壤属性和多样性特征（物种和功能多样性）构建海岛植被近自然度评价指标体系。利用敏感性分析筛选出13个反映海岛植被近自然度的中、高敏感性指标，基于筛选指标用层次分析法初次构建了中国东部海岛植被近自然度评价指标体系，并计算典型海岛的植被近自然度综合指数和划定植被近自然度等级。结果显示：海岛植被近自然度综合评价指标的权重：植被信息 > 多样性特征 > 土壤属性，其中植物自然构成系数、土壤含水量、Shannon-Wiener指数、Rao二次熵指数的权重较大；典型海岛的植被近自然度综合指数在0.345-0.611间，其中大金山岛的植被近自然度最高，属半天然林，北长山岛最低，为近人工林，其他海岛为远天然林；中亚热带的海岛植被近自然度较高，暖温带和南亚热带的海岛植被近自然度较低。本研究基于陆地植被近自然度评价指标，联合植物功能多样性对我国东部海岛植被近自然度进行综合评价，为海岛植被的生态状况提供定量依据，以及为海岛植被保护与管理和近自然恢复提供理论支撑。

Evaluation of vegetation naturalness across 10 islands in eastern China

Vegetation naturalness evaluation is an important theoretical basis of forest natural restoration. Due to the special geographical environment, islands vegetation is different from the mainland in structure and function. However, there is few studies on the island vegetation naturalness evaluation that combined plant functional trait. Based on the vegetation information, soil properties, and diversity characteristics (species and functional diversity) across 74 plant communities of 10 typical islands in eastern China. Thirteen indices with middle and high sensitivity of vegetation naturalness were selected, then the evaluation index system of island vegetation naturalness was constructed by using the analytic hierarchy process. The comprehensive index of vegetation naturalness was calculated and the levels of vegetation naturalness were divided for each island. Our results showed that the weights of vegetation naturalness indexes in the comprehensive evaluation system were vegetation information > diversity characteristics > soil properties, among which the best indexes are plant natural compose index, soil water content, plant Shannon-Weiner index, and Rao''s index. Across 10 islands, the degree of vegetation naturalness was the highest on Da jinshan Island (0.611), representing the semi-natural forest, and the lowest in North Changshan Island (0.345), reflecting the semi-plantation. Among the climatic zones, the degree of vegetation naturalness was relatively lower in the islands of the warm temperate and southern subtropical regions than in those in the middle-subtropical region. The results not only used common indexes of mainland vegetation evaluation, but also combined plant functional diversity, which will help to provide quantitative evidence for the ecological status of island vegetation in eastern China, and also provides support for the island vegetation conservation management and natural restoration.