高原退化湿地纳帕海植物多样性格局特征及其驱动力

对滇西北纳帕海湿地不同退化演替阶段的植物群落结构特征及多样性格局的研究结果表明:纳帕海共有植物115种,隶属38科、82属,植物群落15个,包括3个沉水植物群落、2个浮叶植物群落、6个挺水植物群落、4个草甸群落。其中原生沼泽有湿地植物25种,隶属16科、17属,3个沉水植物群落、2个浮叶植物群落;沼泽化草甸有湿地植物35种,隶属19科、26属,6个挺水植物群落;草甸有湿地植物64种,隶属28科、55属,4个草甸群落;垦后湿地仅有农作物4种,隶属4科、4属。随着原生沼泽、沼泽化草甸向草甸、垦后湿地的退化演替,植物群落伴生种增多,优势种的优势度明显下降,群落结构逐渐变得复杂;原生沼泽、沼泽化草甸植物群落分布面积萎缩,草甸、垦后湿地面积不断增大;物种丰富度与多样性指数随原生沼泽、沼泽化草甸、草甸的退化演替而逐渐增加,草甸植物物种丰富度、多样性指数最大,而垦后湿地为最低值。纳帕海植物多样性格局特征是对不同人为干扰强度与类型的响应,当前影响植物多样格局的驱动力主要是排水垦殖、无序旅游、过度放牧和周边森林的破坏等人为生产活动。

Plant diversity pattern and its driving forces in Napahai, a degraded plateau wetland in northwestern Yunnan, China

The plant community structure and its diversity were studied at Napahai, a selected typical degraded wetland in northwestern Yunnan of Yun-Gui plateau, China. We found Napahai Wetland has 115 species, belonging to 38 families and 82 genera, including 3 submerged plant communities, 2 floating-leaved plant communities, 6 emergent plant communities and 4 meadow plant communities. In the Napahai Wetland, for the primary swamp there were 25 species, belonging to 16 families and 17 genera, including 3 submerged plant communities, 2 floating-leaved plant communities. For the swampy meadow, there were 35 species belonging to 19 families and 26 genera, including 6 emergent plant communities. For the meadow, there were 64 species belonging to 28 families and 55 genera, including 4 meadow plant communities. For the reclaimed wetland there were only 4 species belonging to 4 families and 4 genera. The plant community structure and diversity have changed with the wetland succession from primary swamp to swampy meadow, meadow and reclaimed wetland. The results showed the community structure become complex, the companying species increased and the dominant species decreased. While the plant community distribution area of primary swamp and swampy meadow has been declined, the area of meadow and reclaimed wetland has expanded. Moreover, the species richness and the pant diversity index increased as primary swamp changed to swampy meadow and meadow. The highest species richness occurred in the meadow and the lowest was in the reclaimed wetland. This plant diversity pattern in Napahai Wetland is a response of plant community to human disturbances. Those disturbances are drainage, reclamation, unmanaged tourism, overgrazing in the wetland and vegetation destruction in watershed. To protect the wetland ecosystem is to strengthen management of human activities.