Impacts of preferential flow and agroecosystem management on subsurface particulate phosphorus loadings in tile-drained landscapes.
Impacts of preferential flow and agroecosystem management on subsurface particulate phosphorus loadings in tile-drained landscapes.
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优先流和农业生态系统管理对瓦排水景观中地下颗粒磷负荷的影响。
DOI：
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发表时间：
2020
影响因子：
2.4
通讯作者：
K. King
中科院分区：
文献类型：
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作者：
S. Nazari;W. Ford;K. King
近年来对瓦片排水的研究侧重于溶解活性磷（DRP）的输送和运输途径，而对颗粒磷（PP）的关注较少，导致其被排除在农业水管理模型之外。在这项研究中，我们通过对长期水文和水质数据集的统计分析，量化了PP向瓷砖输送的通量、机制和因素。该数据集包括5年的地表和土壤排放、总磷（TP）、总磷（DRP）、总氮（TN）和溶解无机氮浓度，来自两个具有对比土壤和管理实践的边缘研究点。采用水文曲线衰退技术与多元线性回归相结合的方法来了解水文流动路径，并采用经验模式分解（EMD）时间序列分析来确定PP季节性过程的重要性和管理措施的影响。水文流道分析表明，快流分别占粘土和壤土样地地下流量的66%和36%。磷负荷分析表明，大孔流动对PP向地下输送磷有显著作用，PP对TP和DRP的输送有显著贡献；然而，尽管壤土场地的地下排放和土壤试验磷水平较高，但粘土场地的PP负荷较高。此外，环境条件和管理措施显著影响PP的输送。我们强调了水文曲线衰退分析在识别大孔和弥漫性排水方面的有效性，P/N比率在表征瓦片沉积物输送机制方面的有效性，以及EMD在野外尺度上检测管理对TP和DRP的影响的有效性。
Recent research on tile-drainage has placed emphasis on dissolved reactive phosphorus (DRP) delivery and transport pathways but less emphasis on particulate P (PP), resulting in its exclusion from agricultural water management models. In this study, we quantified the fluxes, mechanisms, and factors driving PP delivery into tiles through statistical analysis of a long-term hydrologic and water quality dataset. The dataset includes 5 yr of surface and tile discharge, total P (TP), DRP, total nitrogen (TN), and dissolved inorganic N concentrations from two edge-of-field study sites with contrasting soil and management practices. Hydrograph recession techniques were coupled with multiple linear regression for understanding hydrologic flow pathways, and empirical mode decomposition (EMD) time-series analysis was used to determine the significance of PP seasonality processes and the effect of management practices. The analysis of hydrologic flow pathways demonstrated that quickflow contributed 66 and 36% of subsurface discharge in the clay and loam sites, respectively. Phosphorus loading analysis showed that macropore flow plays a significant role in PP delivery to subsurface P loading and that PP significantly contributed to TP and DRP delivery; however, greater PP loadings were observed at the clay site despite greater subsurface discharge and soil test P levels at the loam site. Furthermore, PP delivery was significantly affected by environmental conditions and management practices. We highlight the efficacy of hydrograph recession analysis for identifying macropore and diffuse drainage, of P/N ratios to characterize sediment delivery mechanisms in tiles, and of EMD to detect management impacts on TP and DRP at the field scale.