Stream Nitrogen and Phosphorus Loads Are Differentially Affected by Storm Events and the Difference May Be Exacerbated by Conservation Tillage
Stream Nitrogen and Phosphorus Loads Are Differentially Affected by Storm Events and the Difference May Be Exacerbated by Conservation Tillage
复制标题
溪流氮和磷负荷受风暴事件的影响不同，保护性耕作可能会加剧这种差异
DOI：
10.1021/acs.est.8b05152
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发表时间：
2019
影响因子：
11.4
通讯作者：
Vanni, Michael J.
中科院分区：
文献类型：
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作者：
Kelly, Patrick T.;Renwick, William H.;Knoll, Lesley;Vanni, Michael J.
与氮 (N) 相比，风暴事件不成比例地动员溶解的磷 (P)，从而导致 N:P 负荷减少。在农业流域，由于表层土壤中溶解磷的积累，保护性耕作可能导致氮磷负荷进一步下降。由于这种管理活动的增加，我们对风暴事件期间保护性耕作对氮和磷负荷的影响感兴趣。使用富营养化水库 20 年的营养负荷数据集，我们观察到风暴事件期间磷负荷相对于基流不成比例地增加，而氮负荷与排放量成正比。我们还观察到这种关系的变化，即，随着流域内更多的保护性耕作，相对于基流的磷负荷更大。这表明保护性耕作可能有助于显着减少风暴期间的 N:P 负荷，并对受纳水体的水质产生潜在影响。
Storm events disproportionately mobilize dissolved phosphorus (P) compared to nitrogen (N), contributing to reduction in load N:P. In agricultural watersheds, conservation tillage may lead to even further declines in load N:P due to dissolved P accumulation in the top soil layers. Due to an increase in this management activity, we were interested in the impacts of conservation tillage on N and P loads during storm events. Using a 20 year data set of nutrient loads to a hypereutrophic reservoir, we observed disproportionately increasing P loads relative to base flow during storm events, whereas N loads were proportional to discharge. We also observed a change in that relationship, i.e., even greater P load relative to base flow with more conservation tillage in the watershed. This suggests conservation tillage may contribute to significantly reduced N:P loads during storms with potential implications for the water quality of receiving water bodies.