摘要
流域景观特征对流域河流氮(N)磷(P)迁移输出具有显著影响,但不同景观组成与配置与河流N、P输出负荷的关系有待进一步深入研究。以亚热带典型农林混合流域金井河流域为研究区域,基于长期水文、水质定位观测数据定量估算了河流N、P输出负荷。将景观指数分类结合传统统计分析筛选出的不同景观尺度的核心景观指数,采用冗余分析(RDA)和方差分解分析(VPA)明确不同尺度景观格局特征对于河流N、P输出负荷的影响关系。结果表明:流域丰水期、平枯水期N、P输出负荷呈显著时空差异,丰水期流域河流TN、NH_(4)^(+)-N、NO_(3)^(-)-N、TP、DIP输出负荷分别为2.61~9.03、0.34~5.34、1.26~5.03、0.15~0.50、0.09~0.23 kg/(hm^(2).a);平枯水期分别为1.55~6.68、0.29~2.91、0.74~2.91、0.10~0.46、0.05~0.20 kg/(hm^(2).a)。不同景观尺度水平及土地利用类型,景观特征对于N、P输出负荷的影响有所差异,但在同一尺度水平上,各类别景观指数对河流丰水期和平枯水期N、P输出负荷的影响基本一致。景观尺度上,不同类型斑块聚集度、景观多样性的增加会导致河流N、P输出负荷的增加;河流N、P输出负荷与面积大、聚集度高、连通度高的农田、居民地斑块呈显著正相关,与聚集度高、大面积的林地斑块显著负相关。丰水期、平枯水期农田斑块对河流N、P负荷主要影响指数类别分别为面积-边缘和聚集度指数。林地、居民地斑块对N、P负荷主要影响的类别指数分别为面积-边缘和聚集度。研究可从流域景观规划角度为农业面源污染的治理提供理论支持和科学依据。
The characteristics of the river basin landscape have a significant impact on the migration and output of nitrogen(N) and phosphorus(P) in river basins,but its relationship with the output load of river N and P and its contribution need to be further studied.This study takes the Jinjing River Basin as the research area,and quantitatively estimates the river N and P output load based on long~term hydrology and water quality positioning observation data.Based on the classification of landscape index combined with the core landscape index of different landscape scales selected by traditional statistical analysis,redundancy analysis(RDA) and variance analysis(VPA) are used to clarify that the characteristics of landscape pattern at different scales in the typical subtropical agro~forestry mixed watershed are important for river N,P The influence of output load.The results show that the output load of N and P in the river basin during the flood period and the dry and dry period is significantly different in time and space.The output load of TN,NH_(4)^(+)-N,NO_(3)^(-)-N,TP,and DIP in the river basin during the flood period are 2.61-9.03,0.34-5.34,and 0.34-5.34,respectively.1.26-5.03,0.15-0.50,0.09-0.23 kg/(hm~2.a);the flat and dry seasons were 1.55-6.68,0.29-2.91,0.74-2.91,0.10-0.46,and 0.05-0.20 kg/(hm~2.a),respectively.Different landscape scale levels and land use types,landscape characteristics have different effects on N and P output loads,but at the same scale level,the impact of various types of landscape indexes on the N and P output loads of rivers during high and low water periods is basically the same.At the landscape scale,the increase in the concentration of different types of patches and the increase in landscape diversity will lead to an increase in the output load of river N and P;the output load of river N and P is related to the large area,high concentration,and high connectivity of farmland and residential land.Blocks are significantly positively correlated,and significantly negatively correlated with high~aggregation and large~area woodland patches.The main impact index categories of farmland patches on river N and P loads in wet and dry periods are area~margin and aggregation index respectively.The impacts of forest land and residential land patches at different water level periods remained unchanged,and they were respectively the area~margin and agglomeration category indexes.The results of this study can provide theoretical support and scientific basis for the management of agricultural non~point source pollution in the river basin from the perspective of landscape planning.
作者
邓越
唐代生
孟岑
李裕元
李希
宫殿林
李情
沈建林
吴金水
DENG Yue;TANG Dai-sheng;MENG Cen;LI Yu-yuan;LI Xi;GONG Dian-lin;LI Qing;SHEN Jian-lin;WU Jin-shui(School of Forestry,Central South University of Forestry and Technology,Changsha 410018,China;Key Laboratory ofSubtropical Agroecological Process,Institute of Subtropical Agricultural Ecology,Chinese Academy of Sciences,Changsha 410125,China;Institute of Subtropical Agricultural Ecology,Chinese Academy of Sciences,Changsha Agricultural Environment Observation and Research Station,Changsha 410125,China;University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《长江流域资源与环境》
CAS
CSSCI
CSCD
北大核心
2022年第4期937-948,共12页
Resources and Environment in the Yangtze Basin
基金
国家自然科学基金青年项目(42007157)。
关键词
景观格局
景观尺度水平
斑块类型尺度水平
面源污染
landscape pattern
landscape scale level
patch type scale level
non-point source pollution
