蓄水对三峡库区消落带土壤和植被的影响研究进展OA

The water-level fluctuation zone(WLFZ)in Three Gorges Reservoir is a land-water ecotone formed by periodic water level fluctuation in the mainstream and tributaries of the Yangtze River im-pounded by Three Gorges Dam.The operating mode of'storing clear water and discharging muddy water'from Three Gorges Reservoir makes the WLFZ of Three Gorges Reservoir entirely different from natural water-level fluctuation zones.In this study,we reviewed the changes of soil physical and chemical proper-ties and vegetation communities in the WLFZ before and after impoundment of Three Gorges Reservoir over the past ten years.Relevant studies showed that soil pH,soil organic carbon and total nitrogen changed significantly after impoundment.The soil pH gradually tended toward neutral,and the contents of soil organic carbon and total nitrogen decreased with the number of water level fluctuation cycles.Physical properties such as soil texture and bulk density and chemical properties such as soil pH,soil or-ganic carbon and total nitrogen varied with water level elevation.Plant community composition and spe-cies diversity in the WLFZ of the mainstem and tributaries have changed significantly,and many of the original terrestrial plants have not adapted to the altered habitat and died out.Plant composition and diver-sity also varied with location within the WLFZ.Prior to inundation,the dominant species were primarily Cynodon dactylon and Xanthium strumarium and new plant communities have gradually formed.In the future,it is imperative to intensify research on the physiological and ecological responses of pioneer spe-cies within the WLFZ to environmental stressors.Additionally,there is a need to further refine our under-standing of the plant-soil-water coupling dynamics in the WLFZ ecotone.It is also crucial to undertake analysis focusing on the primary loss mechanisms and pathways of soil carbon and nitrogen and conduct-ing long-term,large-scale surveys of the WLFZ ecotone are essential.These efforts,collectively,provide valuable insights and references for ecological restoration and reconstruction endeavors in the WLFZ of Three Gorges Reservoir.