Critical zone structure controls concentration‐discharge relationships and solute generation in forested tropical montane watersheds
Critical zone structure controls concentration‐discharge relationships and solute generation in forested tropical montane watersheds
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临界区结构控制森林热带山地流域的浓度-排放关系和溶质生成
DOI：
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
W. McDowell
中科院分区：
文献类型：
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作者：
A. Wymore;R. Brereton;D. Ibarra;K. Maher;W. McDowell
尽管热带地区向全球海洋贡献了不成比例的溶质，但热带流域的浓度-排放（C-Q）关系却知之甚少。波多黎各的卢基略山脉提供了一个理想的环境，以检查跨异质热带景观的C-Q关系。我们使用10个流域10-30年的每周溪流化学数据来检查风化产物（SiO2（aq），Ca 2+，Mg 2+和Na+）和生物控制溶质（溶解有机碳[DOC]，溶解有机氮[DON]，NH 4+，NO3-，PO 43-，K+和SO 42-）的C-Q关系。我们使用幂律方程和溶质产生模型分析C-Q关系，并使用主成分分析来测试关于临界区结构如何控制溶质产生的假设。火山岩流域有较高浓度的风化溶质和较小的支流约三倍更有效地产生这些溶质比较大的河流。岩性和植被解释了风化溶质理论最大浓度（r2 = 0.43-0.48）以及PO 43-（r2 = 0.63）和SiO2（aq）（r2 = 0.47）的C-Q关系的显著变化。然而，这些关系的方向和程度各不相同。在整个流域，各种形式的N和P显示变量C-Q关系，而DOC始终丰富的流量增加。结果表明，PO 43-可能是一个有用的指示流域功能。C-Q和景观特征之间的关系表明临界区的结构和功能控制流域溶质通量的程度。
Concentration‐discharge (C‐Q) relationships are poorly known for tropical watersheds, even though the tropics contribute a disproportionate amount of solutes to the global ocean. The Luquillo Mountains in Puerto Rico offer an ideal environment to examine C‐Q relationships across a heterogeneous tropical landscape. We use 10–30 years of weekly stream chemistry data across 10 watersheds to examine C‐Q relationships for weathering products (SiO2(aq), Ca2+, Mg2+, and Na+) and biologically controlled solutes (dissolved organic carbon [DOC], dissolved organic nitrogen [DON], NH4+ , NO3– , PO43– , K+, and SO42– ). We analyze C‐Q relationships using power law equations and a solute production model and use principal component analysis to test hypotheses regarding how the structure of the critical zone controls solute generation. Volcaniclastic watersheds had higher concentrations of weathering solutes and smaller tributaries were approximately threefold more efficient at generating these solutes than larger rivers. Lithology and vegetation explained a significant amount of variation in the theoretical maximum concentrations of weathering solutes (r2 = 0.43–0.48) and in the C‐Q relationships of PO43– (r2 = 0.63) and SiO2(aq) (r2 = 0.47). However, the direction and magnitude of these relationships varied. Across watersheds, various forms of N and P displayed variable C‐Q relationships, while DOC was consistently enriched with increasing discharge. Results suggest that PO43– may be a useful indicator of watershed function. Relationships between C‐Q and landscape characteristics indicate the extent to which the structure and function of the Critical zone controls watershed solute fluxes.
影响因子：
2.3
作者：
Hartmann, Jens;Jansen, Nils;Kempe, Stephan
通讯作者：
Kempe, Stephan
影响因子：
3.9
作者：
Hartmann, Jens;Moosdorf, Nils
通讯作者：
Moosdorf, Nils
影响因子：
3.9
作者：
Hartmann, Jens;Jansen, Nils;Koehler, Peter
通讯作者：
Koehler, Peter