A dynamic watershed model for determining the effects of transient storage on nitrogen export to rivers
A dynamic watershed model for determining the effects of transient storage on nitrogen export to rivers
复制标题
用于确定瞬时储存对河流氮输出影响的动态流域模型
DOI：
10.1002/2014wr015852
复制
发表时间：
2014-10-01
影响因子：
5.4
通讯作者：
Dahlgren, Randy A.
中科院分区：
文献类型：
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作者：
Chen, Dingjiang;Hu, Minpeng;Dahlgren, Randy A.
尽管许多地区的人为氮输入量显着下降，但遗留的人为氮（N）被认为是河流氮出口增加的主要原因。然而，关于遗留氮库对河流氮输出的贡献，定量知识很少。本研究开发了动态流域氮输送模型，以解决人为氮输入的瞬时储存对河流氮通量的作用。该模型采用简单的质量平衡和等效替代规则，用一个结合了前一年河流总氮（TN）通量、相关解释变量和未知参数的术语来表达遗留氮质量的瞬时存储，使我们能够使用贝叶斯统计从可测量变量逆向校准模型参数。该模型的有效性通过对中国东部永安河流域 31 年（1980-2010）河流总氮通量记录的应用得到了证明。该模型可以量化遗留氮的年度瞬时储存及其对年度河流氮通量的贡献。该模型还允许对年度人为氮输入的命运（例如，瞬时储存、河流出口、反硝化造成的损失/保留、生物质吸收和木制品出口）划分完整的长期质量平衡。为了进一步改进模型，可以指定各种N个输入输出过程，并且需要对N个命运进行长期测量来进一步验证模型结果。本研究表明需要考虑瞬时储存效应，以改进当前的流域模型以及制定和评估氮污染控制措施。
Legacy anthropogenic nitrogen (N) has been suggested as a major cause for increasing riverine N exports despite significant declines in anthropogenic N inputs in many regions. However, little quantitative knowledge exists concerning the contribution of the legacy N pool to riverine N export. This study developed a dynamic watershed N delivery model to address the role of transient storage of anthropogenic N inputs on riverine N flux. Employing simple mass balance and equivalent substitution rules, the model expresses the transient storage of legacy N mass with a term that combines the previous one year's riverine total N (TN) flux, relevant explanatory variables, and unknown parameters, enabling us to inversely calibrate the model parameters from measurable variables using Bayesian statistics. The model efficacy was demonstrated through application to the Yong'an River watershed in eastern China based on a 31 year record (1980–2010) of riverine TN fluxes. The model can quantify annual transient storage of legacy N and its resulting contribution to annual riverine N flux. The model also allows partitioning of the complete long‐term mass balance for the fate (e.g., transient storage, riverine export, and loss/retention by denitrification, biomass uptake and wood product export) of annual anthropogenic N inputs. To further improve the model, various N input‐output processes can be specified and long‐term measurements of N fates are required to further verify the model results. This study demonstrates the need to consider transient storage effects as an improvement to current watershed models and for developing and assessing N pollution control measures.