Advection, dispersion, and filtration of fine particles within emergent vegetation of the Florida Everglades
Advection, dispersion, and filtration of fine particles within emergent vegetation of the Florida Everglades
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DOI：
10.1029/2007wr006290
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发表时间：
2008-04
影响因子：
5.4
通讯作者：
Yong Huang;J. Saiers;J. Harvey;G. Noe;S. Mylon
中科院分区：
文献类型：
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作者：
Yong Huang;J. Saiers;J. Harvey;G. Noe;S. Mylon
颗粒物在湿地表面沃茨中的运动影响着营养物质循环、污染物迁移和湿地景观的演变。尽管颗粒物输运在影响湿地的形式和功能方面具有重要意义，但很少有数据集以定量的方式阐明含有挺水植被的地表沃茨内颗粒物的输运行为。我们报告了在位于佛罗里达大沼泽地水源保护区3A的湿地现场进行的1 μm乳胶微球输运实验的观测结果。实验涉及在两个4.8米长的表面水槽内注入颗粒的线源，这些水槽建造在Eleocharis斯劳和Cladium jamaicense山脊之间的过渡区和Cladium jamaicense山脊内。我们将颗粒传输的测量结果与二维平流-弥散模型的计算结果进行了比较，该模型考虑了水速度随地表高度的线性增加。分析结果表明，颗粒在脊中通过纵向和垂直扩散的扩散比在过渡区内大得多，水生植被的颗粒捕获降低了地表水颗粒浓度，至少在我们实验的时间尺度上，可以表示为不可逆的一级动力学过程。我们发现，我们基于实地的颗粒扩散和水流速度的估计值与根据已发表的理论确定的估计值之间普遍存在良好的一致性，这表明复杂湿地环境中颗粒物的平流扩散输送可以根据水流和水生植被的可测量特性进行近似。
The movement of particulate matter within wetland surface waters affects nutrient cycling, contaminant mobility, and the evolution of the wetland landscape. Despite the importance of particle transport in influencing wetland form and function, there are few data sets that illuminate, in a quantitative way, the transport behavior of particulate matter within surface waters containing emergent vegetation. We report observations from experiments on the transport of 1 μm latex microspheres at a wetland field site located in Water Conservation Area 3A of the Florida Everglades. The experiments involved line source injections of particles inside two 4.8‐m‐long surface water flumes constructed within a transition zone between an Eleocharis slough and Cladium jamaicense ridge and within a Cladium jamaicense ridge. We compared the measurements of particle transport to calculations of two‐dimensional advection‐dispersion model that accounted for a linear increase in water velocities with elevation above the ground surface. The results of this analysis revealed that particle spreading by longitudinal and vertical dispersion was substantially greater in the ridge than within the transition zone and that particle capture by aquatic vegetation lowered surface water particle concentrations and, at least for the timescale of our experiments, could be represented as an irreversible, first‐order kinetics process. We found generally good agreement between our field‐based estimates of particle dispersion and water velocity and estimates determined from published theory, suggesting that the advective‐dispersive transport of particulate matter within complex wetland environments can be approximated on the basis of measurable properties of the flow and aquatic vegetation.