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为了解海河流域河流生态系统的退化程度,进而为河流植被修复提供支撑,对河流滨岸带植被入侵物种开展调查,并分析其入侵等级、分布规律及成因.调查了海河流域九大水系滨岸带402个样地的植物物种信息和主要环境因子,参照《中国入侵植物名录》确定入侵植物名单,根据物种的出现频率和以该物种为优势种的样地所占比例来评价植物入侵等级,并分析物种入侵与环境因子之间的关系.结果表明:1海河流域河流滨岸带入侵植物共有48种,其中一年生草本植物占72.9%,并且以菊科、苋科、禾本科物种数最多.2Ⅰ级入侵种为反枝苋(Amaranthus retroflexusn)、苘麻(Abutilon theophrasti)、小藜(Chenopodium serotinum)、鬼针草(Bidens pilosa)和鳢肠(Eclipta prostrata)共5个物种,出现频率超过25%;Ⅱ级入侵种为小蓬草(Conyza canadensis)、大狼杷草(Bidens frondosa)、圆叶牵牛(Pharbitis purpurea)等共11种;Ⅲ级入侵种共32种.3各水系平均出现入侵植物23种,其中子牙河水系入侵植物种数最多,为33种;其次为滦河水系,为25种;漳卫河水系最少,为15种.4海拔和堤外土地类型与植物入侵强度相关性最大,海拔与入侵植物的关系主要通过人口压力相关联.
In order to understand the degree of degradation of the river ecosystem in the Haihe River Basin and to provide support for the restoration of river vegetation, we investigated the invasive species, distribution rules and causes of the invasive species in the river bank. Based on the plant species information and major environmental factors of 402 plots, the list of invasive plants was determined with reference to “China Invasive Plant Directory”. The plant invasion grade was evaluated according to the appearance frequency of species and the proportion of plots with the dominant species. And analyzed the relationship between species invasion and environmental factors.The results showed that there were 48 invasive species in the riverside banks of the Haihe River Basin, of which 72.9% were annual herbaceous plants, and the most species were Compositae, Amaranthus and Gramineae. The second-level invasive species were Amaranthus retroflexusn, Abutilon theophrasti, Chenopodium serotinum, Bidens pilosa and Eclipta prostrata, and their frequency of occurrence exceeded 25 %. Grade II intrusives included 11 species including Conyza canadensis, Bidens frondosa and Pharbitis purpurea. A total of 32 kinds of invasive species.3 The average occurrence of invasive plants in each of the 23 species, of which the Ziya River water system invaded plants up to 33 species; followed by the Luanhe River system, 25 species; .4 There was the highest correlation between the type of land and the intensity of plant invasions outside the embankment, and the relationship between the altitude and the invasive plants was mainly through population pressure.