How do macrophyte distribution patterns affect hydraulic resistances?
How do macrophyte distribution patterns affect hydraulic resistances?
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DOI：
10.1016/j.ecoleng.2010.12.018
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发表时间：
2011-03-01
影响因子：
3.8
通讯作者：
Meire, Patrick
中科院分区：
文献类型：
--
作者：
Bal, Kris;Struyf, Eric;Meire, Patrick
在富营养化的河流系统中，水生植物获得高生物量，减少排水和增加洪水的风险。为了避免这些问题，水资源管理人员会清除植被。然而，总清除量增加了大型无脊椎动物群落的冲刷，降低了河流的生态价值。部分植被的去除减少了这种冲刷，并防止液压阻力的增加。本文对三种局部植被去除模式的水力性能进行了试验研究。从结果可以看出，以曼宁n表示的水力阻力在0.025 m（-1/3）s和0.050 m（-1/3）s之间变化。与空载情况相比，不同的分布模式增加了14%至23%的阻力。这些模式的水力阻力也显着影响植被斑块中存在的物种。测定了三组具有显著不同水力阻力的水生植物（浮出、浮叶和沉水）。出现的物种直立黑三棱（Sparganiumerectum）产生的阻力最小，平均摩擦力为0.03m（-1/3）s。梳叶海鞘和游泳眼子菜的摩擦力值略高，约为0.4m（-1/3）s。毛茛和水马齿的平均摩擦力值约为0.05 m（-1/3）s。建议的植被去除模式是创建一个管理系统的良好替代方案，该管理系统最小限度地增加了水力阻力，但仍能保证生态功能。(C)2010 Elsevier B. V.保留所有权利。
In eutrophic river systems, macrophytes attain high biomass with reduced drainage and increased flooding risk. To avoid these problems, water managers remove vegetation. Total removal, however, increases wash out of macro-invertebrate communities reducing the ecological value of rivers. Partial vegetation removal reduces this washout and prevents an increase in hydraulic resistance. In this, study the hydraulic performance of three partial vegetation removal patterns was tested. From the results it was seen that hydraulic resistance, expressed as Manning's n, was varying between 0.025 m(-1/3) s and 0.050 m(-1/3) s. Compared with the empty situation, the different distribution patterns increased resistance between 14 and 23%. Hydraulic resistance of these patterns was also significantly influenced by the species present in the vegetation patches. Three groups of macrophyte plants (emerged, floating leaved and submerged) with significantly different hydraulic resistances were determined. The emerged species Sparganium erectum generated the least resistance with an average friction of 0.03 m(-1/3) s. Stuckenia pectinata and Potamogeton natans had slightly higher friction values around 0.4 m(-1/3) s. Ranunculus penicillatus and Callitriche platycarpa had average friction values around 0.05 m(-1/3) s.The proposed vegetation removal patterns are good alternatives to create a management system, which minimally increases hydraulic resistance but still guarantees the ecological functions. (C) 2010 Elsevier B.V. All rights reserved.