摘要
研究香溪河流域景观强度指数对河流生态系统的影响,旨在拓展蓄水后水环境演变的理论,并为生态修复决策提供有效的依据。2014年2月到2019年12月,在香溪河河口、中游以及上游回水末端8个采样点连续进行水质监测,分析了营养状态的时空变化,并基于采样点范围和距长江干流的距离将研究区域划分为T1和T2两个小流域,量化了不同流域景观发展强度(LDI)。结果表明:(1)2014-2019年,T1流域的农田面积和不透水表面面积分别增加了2.80%和0.11%,森林面积减少了2.84%,T2流域的农田面积和不透水表面面积分别增加了2.84%和0.17%,森林和草地面积有所减少,2个流域的景观发展强度指数均逐年显著增加,T2流域的LDI高于T1流域;(2)T1和T2流域的平均综合营养水平指数分别为42.03和46.21,两个流域的富营养化频率逐年增加,T2出现的频率高于T1,T1和T2流域的最大TLI值均出现在2014年,分别为60.63和78.59,分别处于中营养、超富营养状态,TP和COD是重要影响因素;(3)LDI与T1流域的河流营养状态(r^(2)=0.88,P<0.01)和富营养频率(r^(2)=0.95,P<0.01)之间存在显著的正相关关系,T2流域的营养状态和富营养频率随LDI的增加呈增长的趋势,但在P=0.01水平上不显著。香溪河水体营养状态在小流域尺度对LDI有很好的响应,量化的人类活动模型可以解释土地利用覆盖多种组合的效应,为决策者提供了更加多样化的土地利用配置选项,以减少人为改造对自然环境的影响。
Landscape development intensity(LDI) is highly related to wetland biodiversity, and the pH,TP concentration and conductivity of soils, parameters widely used to evaluate the health of wetland ecosystems. In this study, we explored the impacts of landscape development intensity on the river ecosystems of the Xiangxi River basin, aiming to expand the theory of water environment evolution after impoundment and provide an effective basis for ecological restoration. Eight sampling sites were set at the cove, midstream, and end of the upstream backwater of Xiangxi River and continuous in-situ water quality monitoring was conducted from February 2014 to December 2019. The study area was divided into two sub-watersheds based on the scale of sampling sites and the distance from the mainstream of the Yangtze River: Subwatershed T1 was close to the mainstream of the Yangtze River with the area of200.93 km2 and Subwatershed T2 was far from the mainstream with the area of 223.67 km2. The intensity of landscape development in different sub-watersheds was quantified, and the spatio-temporal dynamics of the comprehensive trophic status of the two sub-watersheds were analyzed. The land use types in the study area included farmland, forest, shrub land, grassland, surface water and impervious surfaces.Results show:(1) The areas of farmland and impervious surface in T1 increased, respectively, by 2.80%and 0.11% from 2014 to 2019, and the forest area decreased by 2.84%. The respective areas of farmland and impervious surface in T2 increased by 2.84% and 0.17%, and the area of forest and grassland decreased. The LDI of the two sub-watersheds increased significantly year by year and the LDI of T2was higher than that of T1, increasing from 1.7290 to 1.7694 in T1 and from 2.0146 to 2.0566 in T2;(2) The average trophic level index(TLI) of T1 and T2 were 42.03 and 46.21, respectively. The maximum TLI in T1(60.63) and T2(78.59) both appeared in 2014, indicating mesotrophic and hypereutrophic conditions. The frequency of eutrophic conditions
作者
李渊
张明华
房婉蓉
吉莉
王愿珠
米武娟
毕永红
LI Yuan;ZHANG Ming-hua;FANG Wan-rong;JI Li;WANG Yuan-zhu;MI Wu-juan;BI Yong-hong(Taiyuan University of Science and Technology,School of Environmental Science and Engineering,Taiyuan 030024,P.R.China;State Key Laboratory of Freshwater Ecology and Biotechnology,Institute of Hydrobiology,Chinese Academy of Sciences,Wuhan 430072,P.R.China)
出处
《水生态学杂志》
CSCD
北大核心
2022年第5期8-14,共7页
Journal of Hydroecology
基金
国家自然科学基金项目(31971477,42177057)。
关键词
三峡水库
香溪河流域
营养状态
富营养化
景观发展强度
Three Gorges Reservoir
Xiangxi River basin
trophic status
eutrophication
landscape development intensity
