摘要
为探究九曲河典型农业区域氮磷消纳和负荷空间特征,本研究基于2022—2023年期间的系统采样与分析,结合“农田流失-沿程消纳-水体负荷”水质响应模型(NutriShed),全面探讨了流域内氮磷流失量、消纳量及负荷量的空间分布。结果表明:九曲河干流的总磷(TP)月均浓度在0.02~0.12 mg·L^(-1),总体维持在Ⅱ类水质(0.1 mg·L^(-1)),而支流磷平均浓度变化范围为0.03~0.23 mg·L^(-1),波动较大,部分时段超Ⅲ类水质标准(0.2 mg·L^(-1)),春夏季污染尤为严重;干流与支流的总氮(TN)月均浓度超2.00 mg·L^(-1),支流平均TN浓度高于干流20.4%,且以铵态氮为主要氮污染形态。冬春交替和夏季是氮污染高发期,其中农宴河、永胜河等支流为污染热点区域,空间分布表现为上游农业活动密集区和居民聚集区负荷量最高。NutriShed模型模拟结果进一步揭示,2022—2023年流域TN流失量为404 t,沿途消纳量为147 t,占总量的36.4%,负荷量为257 t;2022—2023年磷的总流失量为57.2 t,沿途消纳量为33.6 t,占58.7%,负荷量为23.6 t。模型分析表明,氮磷含量较高的农宴河等支流是精准治理的重点区域。基于研究结果,建议通过优化施肥管理、合理布局河道生态缓冲区以及精准治理高污染支流等措施,提升面源污染综合治理能力。
In order to explore the spatial characteristics of nitrogen(N)and phosphorus(P)absorption and load in the typical agricultural area of Jiuqu River,this study,based on the systematic sampling and analysis during the period from 2022 to 2023,combined with the water quality response model(NutriShed)of"farmland loss-along-the-way absorption-water body load",comprehensively discussed the spatial distribution of nitrogen and phosphorus loss,absorption and load in the watershed.The results showed that the monthly average total phosphorus(TP)concentration in the main stream of the Jiuqu River ranged from 0.02 to 0.12 mg·L^(-1),generally maintaining ClassⅡwater quality standards(0.1 mg·L^(-1)).In contrast,TP concentrations in tributaries fluctuated more widely,ranging from 0.03 to 0.23 mg·L^(-1),with some periods exceeding ClassⅢstandards(0.2 mg·L^(-1)),especially during spring and summer when pollution was more severe.The monthly average total nitrogen(TN)concentrations in both the main stream and tributaries exceeded 2.00 mg·L^(-1).The average TN concentration in tributaries was 20.4%higher than in the main stream,with ammonium nitrogen being the primary nitrogen pollution form.The transition from winter to spring and the summer season were identified as peak periods for nitrogen pollution,with tributaries such as the Nongyan River and Yongsheng River serving as pollution hotspots.Spatially,the highest N and P loads were observed in upstream areas with intensive agricultural activities and densely populated residential zones.Simulations using the NutriShed model further revealed that the annual TN loss in the basin amounted to 404 t,with 147 t attenuated along the way,accounting for 36.4%,and a remaining load of 257 t from 2022 to 2023.The total annual loss of P loss was 57.2 t,with 33.6 t(58.7%)attenuated and a remaining load of 23.6 t from 2022 to 2023.The model analysis highlighted that tributaries with higher N and P concentrations,such as the Nongyan River,are priority areas for targeted remediation.Based on the study results,it is recommended to enhance comprehensive management of non-point source pollution through measures such as optimizing fertilizer application,rationally planning riparian ecological buffer zones,and implementing targeted remediation for highly polluted tributaries.
作者
苏卫华
王海翔
陈浩
严星
夏永秋
管瑞雪
王慎强
汪玉
SU Weihua;WANG Haixiang;CHEN Hao;YAN Xing;XIA Yongqiu;GUAN Ruixue;WANG Shenqiang;WANG Yu(State Key Laboratory of Soil and Sustainable Agriculture,Institute of Soil Science,Chinese Academy of Sciences,Nanjing 211135,China;University of the Chinese Academy of Sciences,Beijing 100049,China;Zhenjiang Ecological Environment Bureau,Jiangsu Province,Zhenjiang 212050,China)
出处
《农业环境科学学报》
北大核心
2025年第8期2064-2074,共11页
Journal of Agro-Environment Science
基金
江苏省自然科学基金项目(BK20230049)
长江生态环境保护修复联合研究二期项目(2022-LHYJ-02-0502-05)。
关键词
面源污染
氮磷消纳
氮磷负荷
空间分异
九曲河
non-point source pollution
nitrogen and phosphorus retention
nitrogen and phosphorus load
spatial differentiation
Jiuqu River
