An Environmental Fluid Dynamics Laboratory in the Field: studies and numerical modeling of hydrodynamics, morphodynamics and invertebrate ecology in river meanders

湍流控制着河流的输运过程、形态动力学以及生态系统功能。尽管增加了计算能力，令人不安的不确定性仍然存在于复杂的自然水体的建模。拟议的研究通过实验室，数值和现场规模的方法来研究曲流弯道中复杂的水流，形态和生态之间的关系，包括它们对水生无脊椎动物分布和食物资源利用的影响。实地研究将通过数值模拟进行推广，这将有助于完善生态模拟。对两条低地河流弯曲段的水动力和形态动力学研究将提供关于横截面（河床形态和组成）和流动模式（平均流、二次流和湍流）的详细数据集，并将有助于拟订和验证数字代码。这些水文形态学数据将与生境和食物供应、无脊椎动物分布、漂移和多样性以及由此产生的食物网结构变化有关。这将有助于为这些生物变量开发一种改进的建模方法。拟议的研究是IGB-TU德尔夫特浅混合层联合研究项目的后续项目，也是IGB、TU德尔夫特和EPF洛桑关于曲流弯曲的更大联合研究项目的一部分。

Turbulent flows govern transport processes, morphodynamics and thus also ecosystem functioning in rivers. In spite of increased computational capacity, uncomfortable uncertainties still persist in the modeling of complex natural water bodies. The proposed research examines by linked laboratory, numerical and field-scale approaches the relationships between complex flow, morphology and ecology in meander bends, including their effect on aquatic invertebrate distribution and use of food resources. The field studies will be generalized by numerical simulations which will contribute to refine ecological modeling. The hydrodynamic and morphodynamic studies in bended sections of two lowland rivers will provide detailed datasets on the cross-sections (bed morphology and composition) and on flow patterns (mean, secondary and turbulent flows), and will facilitate the elaboration and validation of numerical codes. These hydromorphological data will be related to those on habitat and food availability, invertebrate distribution, drift and diversity, and resulting changes in food web structure. This will enable to develop an improved modeling approach for these biological variables. The proposed research is a follow-up project of a joint IGB-TU Delft research project on shallow mixing layers, and is part of a larger joint research program on meander bends by IGB, TU Delft and EPF Lausanne.