Development of Quantitative, Hydrodynamic and Biological Models of Settlement of Planktonic Larvae of Benthic Animals

埃克曼博士和他的合作者将开发一些通用的定量模型，旨在评估运输、湍流混合和剪切、幼虫发育和幼虫行为在产生底栖无脊椎动物浮游幼虫定居速度的时空变异性方面的相对作用。重点将主要但不完全集中在底栖浮游幼虫面临的独特问题上。这些研究人员将首先创建简单、稳定的一维模型，使我们能够评估选定的边界上的幼虫通量条件，并评估许多重要的比例变量对沉降率的相对影响。在一维模型中研究的变量将包括底部粗糙度特征的规模和密度、边界剪切速度(包括对幼虫施加的升力和阻力)、湍流混合、幼虫游动、幼虫对底物的选择以及幼虫定居的能力程度。这些模型的开发和评估将包括对幼虫行为和定居的实验室研究，以确保准确性。这些模型将指出哪些比例变量必须纳入，哪些可以合理地从更接近模拟现场情况的更复杂的模型中删除。埃克曼博士等人。将构建和评估一系列更复杂、更理想的模型，这些模型具有更广泛的生态相关性。这些模型将包括考虑风浪或潮汐强迫的随时间变化的流动，以及包含底部粗糙度或深度水平梯度的二维稳定流动。因此，这项研究将把物理动力学、生物发展和行为纳入定量公式。这项工作将对几种与生态相关的情况下幼虫在空间和时间上的安置率的变异性进行预测。对于每一种情况，模型将显示幼虫沉降率对一套潜在重要的水动力和生物过程的相对敏感性。拟议的研究包括简化和可预测性的概念性研究，以及理想化流场中生物过程的原型调查--这两类研究旨在支持GLOBEC的建模计划。

Dr Eckman and collaborators will develop some general, quantitative models designed to assess the relative roles of transport, turbulent mixing and shear, larval development and larval behavior in producing spatial and temporal variability in rates of settlement of planktonic larvae of benthic invertebrates. The focus will be largely, but not exclusively, on unique problems faced by planktonic larvae of benthic existence. These investigators will begin by creating simple, steady, 1-dimensional models that should enable us to evaluate selected larval flux conditions at the boundary, and to assess the relative influence of many important scaling variables on settlement rate. Variables studied in 1-D models will include the scale and density of bottom roughness features, boundary shear velocity (including lift and drag forces exerted on larvae), turbulent mixing, larval swimming, substrate selectivity by larvae, and the degree of larval competence to settle. The development and evaluation of these models will include laboratory studies of larval behavior and settlement to ensure accuracy. The models will indicate which scaling variables must be incorporated, and which can reasonably be deleted, from more complex models that more closely mimic field situations. Dr. Eckman et al. will build and evaluate a series of more complex, ideal models, which have broader ecological relevance. These models will include time-dependent flows that account for wind-wave or tidal forcing, and 2-dimensional, steady flows that incorporate horizontal gradients in bottom roughness or depth. Thus, the research will incorporate physical dynamics, biological development and behavior into quantitative formulae. This work will generate predictions of variability in rates of larval settlement in space and time for several ecologically relevant situations. For each case, the models will indicate the relative sensitivity of larval settlement rates to a suite of potentially important hydrodynamic and biological process. The research proposed includes conceptual studies of simplification and predictability, and prototype investigations of biological processes in idealized flow fields - two categories of research targeted for support under GLOBEC's modelling program.