Seed rain and seed bank of a draw-down zone and their similarities to vegetation under the regulated water-level fluctuation in Xiangxi River

Journal of Freshwater Ecology

Yang Wu¹  Miao Zhang¹  Fangqing Chen²  Yongwen Huang² 

[1] Engineering Research Center of Eco-environment in the Three Gorges Reservoir Region, Ministry of Education, China Three Gorges University;Hubei International Scientific and Technological Cooperation Center of Ecological Protection and Management in the Three Gorges Area, China Three Gorges University;

关键词: species composition;    spatial distribution;    life-form;    similarity;    three gorges project;   

DOI  :  10.1080/02705060.2019.1670744

来源: DOAJ

【 摘 要 】

Construction of the Three Gorges Reservoir converted areas of the original terrestrial ecosystem along the shores into a draw-down zone with a fluctuating water-level at an elevation ranging between 145 and 175 m. The water-level fluctuation is regulated against the normal seasonal flooding with summer emergence and winter submergence. We investigated the seed rain and soil seed banks along elevational gradients of the Xiangxi zone in the reservoir to explore the characteristics of species composition and spatial distribution of seed rain and soil seed bank, and their similarities with standing vegetation under the regulated water-level fluctuation. The results showed that the seed rain and soil seed bank comprised 36 and 50 species of plants, respectively. These were predominantly annual herbaceous plants, which accounted for 54.02 and 66.0% of the seed rain and soil seed bank, respectively, with an average density of 445.16 ± 49.97 and 7322.18 ± 678.44 seeds/m2, respectively. The regulated water-level fluctuation resulted in greater species diversity and seed density of seed rain and soil seed bank in the middle and upper elevations of the zone than that of the lower elevations. The similarity coefficient between seed rain and seed bank, seed bank and extant vegetation, seed rain and extant vegetation was 0.488, 0.373 and 0.466, respectively. Effects of the regulated water-level fluctuation on the species compositions and spatial distribution of the seed rain and seed bank, and their similarities with existing vegetation were further discussed by contrast with the current research in the same field.

【 授权许可】

Unknown