Plant community characteristics and their responses to environmental factors in the water level fluctuation zone of the three gorges reservoir in China

• Published in: Environmental science and pollution research international Vol. 20; no. 10; pp. 7080 - 7091
• Main Authors: Zhang, Zhiyong, Wan, Chengyan, Zheng, Zhiwei, Hu, Lian, Feng, Kun, Chang, Jianbo, Xie, Ping
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.10.2013; Springer Nature B.V
• Subjects: Altitude; analysis; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Biodiversity; Biomass; Canyons; chemistry; China; classification; Cynodon dactylon; Cyperus rotundus; Dams; Daucus carota; Digitaria sanguinalis; Dominant species; Earth and Environmental Science; Ecotoxicology; Elevation; Environment; Environmental Chemistry; Environmental factors; Environmental Health; Environmental impact; Factor analysis; Floods; Floods - statistics & numerical data; Flowers & plants; Fresh Water; Fresh Water - analysis; herbs; Hydrology; interspecific variation; phosphorus; Phosphorus - analysis; Physical properties; Plant communities; Plant species; Plants; Plants - classification; Processes and Environmental Quality in the Yangtze River System; Reservoirs; River basins; Seasons; Setaria viridis; Shorelines; Soil; Soil - chemistry; Soil contaminants; Soil nutrients; Soil physical properties; Soil properties; Species composition; species diversity; statistics & numerical data; Studies; Temporal variations; Topography; vascular plants; Vegetation; Waste Water Technology; Water level fluctuations; Water levels; Water Management; Water Pollutants, Chemical; Water Pollutants, Chemical - analysis; Water Pollution Control; Water resources; Water Supply; winter; China; China, People's Rep., Sichuan Prov., Changjiang R., Three Gorges Dam; China, People's Rep; Submergence; Soil properties; Three Gorges Reservoir; Dominant species; Diversity
• ISSN: 0944-1344; 1614-7499; 1614-7499
• DOI: 10.1007/s11356-013-1702-1

The annual water level regulating of the Three Gorges Reservoir prolonged the submerged duration (from 2 to 8 months) and resulted in the reversal of natural flood rhythms (winter submerged). These changes might alter plant community characteristics in the water level fluctuation zone (WLFZ). The aim of this study was to determine the plant community characteristics in the WLFZ and their responses to the environmental factors (i.e., annual hydrological regulation, topographic characteristics, soil physical properties and soil nutrients). The height, coverage, frequency and biomass of each plant species and the soil properties at each elevation zone (150, 155, 160, 165 and 170 m) were measured from March to September in 2010. Univariate two-factor analysis and redundancy analysis (RDA) were used to analyze the spatial and temporal variations of the community characteristics and identify the key environmental factors influencing vegetation. We found that 93.2 % of the species analysed were terrestrial vascular plants. Annual herbs made up the highest percentage of life forms at each altitude. The differences in the species number per square metre, the Shannon–Wiener diversity index and the biomass of vegetation demonstrated statistical significance with respect to sampling time but not elevation. The most dominant species at altitudes of 150, 155, 160, 165 and 170 m were Cynodon dactylon , Cyperus rotundus , Digitaria sanguinalis , Setaria viridis and Daucus carota , respectively. The concentrations of soil nutrients appeared to be the lowest at an altitude of 150 m, although the differences with respect to elevation were not significant. The results of the RDA indicated that the key factors that influenced the species composition of vegetation were elevation, slope, pH and the concentration of soil available phosphorus.