青山湖流域景观格局对河流氮磷营养盐影响的时空尺度效应  

Spatial and Temporal Scale Effects of Landscape Pattern on Riverine Nitrogen and Phosphorus Nutrients in the Qingshan Lake Watershed

作　　者：徐佳妮 刘东鑫 黄赛宇 倪思琪 李冰妍 何圣嘉 邬建红 姜培坤[1,2] XU Jia-ni;LIU Dong-xin;HUANG Sai-yu;NI Si-qi;LI Bing-yan;HE Sheng-jia;WU Jian-hong;JIANG Pei-kun(College of Environmental and Resources,College of Carbon Neutrality,Zhejiang A&F University,Hangzhou 311300,China;State Key Laboratory of Subtropical Silviculture,Zhejiang A&F University,Hangzhou 311300,China)

机构地区：[1]浙江农林大学环境与资源学院,碳中和学院,杭州311300 [2]浙江农林大学省部共建亚热带森林培育国家重点实验室,杭州311300

出　　处：《环境科学》2024年第7期4014-4022,共9页Environmental Science

基　　金：国家自然科学基金项目(42201122,42277045);学校科研发展基金项目(2022LFR020);浙江农林大学学生科研训练项目(2023KX026)。

摘　　要：景观格局对水质的影响具有时空尺度依赖性,然而不同空间尺度下景观组成、景观配置及景观坡度对季节性水质的影响程度仍然不甚明了.基于青山湖流域26个监测点的总氮、总磷、硝态氮和铵态氮数据,采用景观格局分析、冗余分析和偏冗余分析方法定量景观格局对河流氮磷营养盐影响的时空尺度效应.结果表明:(1)子流域尺度内景观格局对河流氮磷浓度的解释力比在缓冲区尺度上高6.8%~8.4%,且这种作用在干季更明显.(2)在子流域尺度,林地占比和居民地的散布分裂程度对河流氮磷浓度影响较大;而缓冲区尺度上,农田和居民地分布的坡度以及林地斑块的聚集度是影响氮磷浓度的关键因子.(3)景观配置对河流氮磷浓度变化的独立贡献率(20.1%~36.5%)高于景观组成(4.1%~14.5%)和景观坡度(5.5%~23.7%)的独立贡献率,且景观配置对河流氮磷浓度影响随季节变化的敏感度最高,而景观坡度对河流氮磷浓度影响具有更高的空间尺度敏感性.因此,通过景观格局调控非点源污染应从多尺度角度考虑.研究结果可从宏观上为制定以非点源污染控制为目标的景观格局优化措施提供科学依据.The influences of landscape pattern on water quality are dependent on spatial-temporal scales.However,the effects of landscape composition,landscape configuration,and landscape slope metrics on seasonal water quality at different spatial scales remain unclear.Based on the total nitrogen,total phosphorus,nitrate-N,and ammonium-N data from 26 sampling sites in the Qingshan Lake watershed,this study coupled landscape pattern analysis,redundancy analysis,and partial redundancy analysis to quantify the spatiotemporal scale effects of landscape pattern on riverine nitrogen(N)and phosphorus(P)concentrations.The results showed that:①The explanatory ability of landscape pattern at the subwatershed scale on riverine N and P concentrations was 6.8%-8.4%higher than that at the buffer scale,and this effect was more obvious in the dry season.②At the sub-watershed scale,the percentage of forestland and the interspersion and juxtaposition degree of residential land had a greater influence on riverine N and P concentrations.At the buffer scale,the slope of farmland and residential land and the aggregation degree of forestland patches were the key factors affecting riverine N and P concentrations.③The contribution rate of landscape configuration to riverine N and P concentration variations(20.1%-36.5%)was the highest.The sensitivity of the effect of landscape configuration on riverine N and P concentrations to seasonal changes was the highest,and the effect of landscape slope on riverine N and P concentrations had the highest sensitivity to spatial scale changes.Therefore,landscape pattern-regulated non-point source pollution should be considered from a multi-scale perspective.These results can provide scientific basis for the formulation of landscape pattern optimization measures aiming at non-point source pollution control.

关 键 词：景观格局 坡度 非点源污染 氮磷营养盐 尺度效应 

分 类 号：X522[环境科学与工程—环境工程] X821