摘要
为探讨东南山丘区水库流域不同空间尺度下景观格局对水质的影响,基于珊溪-赵山渡水库上游支流15个监测断面水质及流域土地利用数据,提取子流域和6种河岸带缓冲区空间尺度上的景观格局信息,运用冗余分析方法定量探讨不同尺度景观格局与水质的关系,识别水质资源管理的最佳空间尺度及关键景观指标。结果表明:(1)水质指标时空尺度上存在显著差异,其中p H、总氮、氨氮空间差异显著(P<0.05),里光溪、南浦溪、莒江溪及玉溪为主要污染风险区域,总氮浓度表现为雨季低于旱季;(2)流域内林地和草地占比最大,为主要的“汇”景观,建设用地、耕地为主要“源”景观,最大斑块指数(LPI)与水质成正相关,散布与并列指数(IJI)、香农多样性指数(SHDI)在多数时空尺度与水质成负相关;(3)景观格局对水质的影响存在空间尺度效应,100 m及800 m河岸带尺度总解释率优于其他尺度,雨季水质主要受草地、林地、建设用地、水域、LPI和SHDI的影响,旱季水质主要受建设用地、耕地和IJI影响。流域内景观格局对水质影响的最佳管理尺度为800 m河岸带,优化该尺度内的景观格局,综合考虑近水体“源”景观的集聚,防控100 m河岸带污染物排放与迁移,对于保障珊溪-赵山渡水库饮用水安全具有重要意义。
Shanxi-Zhaoshandu reservoir is an important water source for Wenzhou City in Zhejiang Province and is typical of riverine reservoir in the southeastern hilly region of China.Based on the water quality data from 15 monitoring sections in the upstream tributaries of Shanxi-Zhaoshandu reservoir and watershed land use data,we explored the influence of landscape patterns on water quality in the reservoir basin at different spatial scales,and identified key landscape indicators and the best spatial scale for water quality resource management.Information on landscape patterns was extracted at different spatial scales in the subbasins and six types of riparian zone buffers.Redundancy analysis was then used to quantitatively explore the relationship between landscape patterns and water quality at different scales.Results show that:(1)There were significant differences in water quality indicators at the spatial and temporal scales and pH,total nitrogen and ammonia nitrogen varied significantly(P<0.05).Liguang stream,Nanpu stream,Jujiang stream and Yuxi stream were regions of high pollution,and the total nitrogen concentration in the rainy season was lower than in the dry season.(2)Forest land and grassland were the dominant land use types in the watershed and the primary pollutant sinks,while urban construction and cropland were the primary pollutant sources.Water quality had a positive relationship with the largest patch index(LPI),and a negative relationship with the interspersion and juxtaposition index(IJI),and the Shannon diversity index(SHDI)at most spatial and temporal scales.(3)The landscape pattern had a spatial scale effect on water quality,with the total explanation rate of 100 m and 800 m riparian zone scale better than other scales.Water quality in the rainy season was primarily influenced by grassland,forest land,urban construction land,water area,LPI and SHDI,and water quality in the dry season was primarily influenced by urban construction land,cropland and IJI.In conclusion,the management scale of landscape pattern with the best influence on water quality in the watershed is the 800 m riparian zone.Furthermore,to ensure the drinking water safety of Shanxi-Zhaoshandu reservoir,it is important to optimize the landscape pattern at the scale of 800m riparian zone,comprehensively consider the aggregation of source landscape on nearby water bodies,and to prevent and control discharge and migration of pollutants in the 100m riparian zone.
作者
张鹏
刘慧
王为木
夏继红
刘昊霖
ZHANG Peng;LIU Hui;WANG Wei-mu;XIA Ji-hong;LIU Hao-lin(College of Agricultural Science and Engineering,Hohai University,Nanjing 211100,P.R.China)
出处
《水生态学杂志》
CSCD
北大核心
2023年第3期17-25,共9页
Journal of Hydroecology
基金
国家重点研发计划项目“生态灾害对渔业生境和生物多样性的影响及其预测评估”(2018YFD0900805)。
关键词
景观格局
地表水质
尺度效应
冗余分析
山丘区水库
landscape pattern
surface water quality
scale effect
redundancy analysis
reservoir in hilly region