草业科学2018，Vol.35Issue(5)：1013-1021,9.DOI:10.11829/j.issn.1001-0629.2017-0651
高寒草甸湿润与干旱化生境中植物多样性的海拔分布格局
Distributional patterns of seed plant diversity in wet and aridification habitats along an elevational gradient in an alpine meadow
摘要
Abstract
Because of the influence of global change and external disturbances,habitats of alpine meadows are trending toward aridification in the Qinghai-Tibetan Plateau.How would variation in habitat affect the eleva-tional pattern of species diversity? Nine sample plots were set along an elevational gradient in the Dongda Mountains in southeast Tibet.Ten 1 m×1 m sample quadrats were set in each sample plot,with five quadrats located in wet habitat and the others located in dry habitat.Species composition in each quadrat was investiga-ted.Species with a frequency lower than seven were defined as occasional species;otherwise,the species were common.For total occasional and common species,variation ofα,β,andγdiversity were respectively analyzed along the elevational gradient.β diversity was measured by the Cody index(βc),multiplicative partitioning (βw),and the slope of regression between similarity of species composition and distance(βslope).There were 160 seed plants recorded in these sample plots,among which,132 species were distributed in wet habitats and 107 species in dry habitats.For total and occasional species,αandγdiversity both decreased with elevational gain in wet habitats but increased in dry habitats.For common species,αandγdiversity both presented an increasing trend with elevational gain in wet and dry habitats.The elevational patterns ofβindexes were not consistent,βc andβwin wet habitats were higher than that in dry habitats,andβcandβwof occasional species was higher than that of common species.The elevational patterns of species diversity between wet and dry habitats were differ-ent,and diversity of occasional species had a high value,and will directly affect elevational patterns of species diversity.关键词
偶见种/β多样性/藏东南/湿润生境/干旱生境Key words
occasional specis/βdiversity/Southeast Tibet/wet habitat/dry habitat分类
农业科技引用本文复制引用
张大才,李双智,张锐..高寒草甸湿润与干旱化生境中植物多样性的海拔分布格局[J].草业科学,2018,35(5):1013-1021,9.基金项目
国家自然科学基金(31660054) （31660054）
