金马河沿岸次生林苔藓植物群落对人为干扰的响应

Response of bryophyte community to anthropogenic disturbances in secondary woodland along the Jinma River

为探索人为干扰对四川金马河沿岸次生林苔藓植物群落的影响,通过分析比较不同干扰程度(轻度、中度、重度)区域苔藓植物的生态位、多样性、生活型、生长附着基质,研究苔藓植物群落特征和物种分布规律。结果表明,在金马河沿岸次生林地12块样地中共调查到苔藓植物15科23属34种,其中,苔类植物3科4属4种,藓类植物12科19属30种。优势科主要为青藓科和羽藓科,其中,细叶小羽藓具有最大的重要值和生态优势度,其重要值、生态位宽度和生态优势度分别为0.5368、2.4648、0.1169,占据重要生态位,台湾青藓次之。耐旱性强的丛集型苔藓植物种类随着人为干扰程度的增强而增加,占比从30.43%逐渐增至40.91%,且其重要值在重度干扰区位于前列。重度干扰区苔藓植物群落的物种丰富度指数和Shannon-Wiener多样性指数均显著低于轻、中度干扰区(P<0.05),中度干扰区苔藓植物群落的Pielou均匀度指数显著高于其他两个干扰区(P<0.05)。重度干扰区苔藓植物附着在腐(枯)木的数量显著少于轻度干扰区(P<0.05),附着在树干的数量显著少于中度干扰区(P<0.05),且主要附着在土壤和岩石上,附着基质逐渐倾向于单一类型。金马河沿岸次生林重度干扰区的苔藓植物物种丰富度指数、Shannon-Wiener多样性指数显著降低(P<0.05),过度干扰会导致林地内生态环境和苔藓植物群落结构遭受破坏。

We studied the characteristics of the community and distribution patterns of bryophytes under different levels of anthropogenic disturbances(mild interference,moderate interference,and severe interference)by analyzing their ecological niches,diversity indexes,life forms,and growing substrates to explore the effects of anthropogenic disturbances on bryophyte communities in secondary woodland along the Jinma River in Sichuan Province.In total,34 species from 15 families and 23 genera of bryophytes were documented,including 4 species of liverworts and 30 species of mosses.The dominant families were Brachytheciaceae and Thuidiaceae(a class of dankness bryophytes),with Haplocladium microphyllum exhibiting the highest importance value and ecological dominance.Its importance value,ecological niche width,and ecological dominance were 0.5368,2.4648,and 0.1169,respectively.Haplocladium microphyllum occupied an important ecological niche,followed by Brachythecium formosanum.The proportion of life from turf bryophyte species increased from 30.43%to 40.91%with higher levels of anthropogenic disturbance,and their importance values were highest in the severe interference area.Turf bryophytes exhibited high drought tolerance and adaptability.The bryophyte species richness and Shannon-Wiener diversity indices of the severe interference area were significantly lower than those of the mild and moderate interference areas(P<0.05),and the Pielou evenness index of the moderately disturbed area was significantly higher than that of the other disturbed areas(P<0.05).In the severe interference area,the number of mosses attached to rotten(dead)trees was significantly lower than that in the mild interference area(P<0.05),and the number of mosses attached to tree trunks was significantly lower than that in the moderate interference area(P<0.05).Moss species were primarily attached to soil and rock,and the substrate favorable for bryophyte colonization gradually narrowed to a single type.The species richness and Shannon-Wiener diversity indices of the bryophyte community in the severe interference area significantly decreased in secondary woodlands(P<0.05).Therefore,excessive disturbance could result in the destruction of both the ecological environment and bryophyte community structure within the woodland.