Lake Basin Characteristics and Morphometry

Abstract

Limnological analyses of a lake or stream very often require a detailed knowledge of morphometry, particularly of the volume characteristics of the body of fresh water. Depth analyses, including measurement of areas of sediments and of water strata at various depths, volumes of strata, and shoreline characteristics, are often critical to detailed analyses of biological, chemical, and physical properties of fresh waters. Morphometric parameters are needed, for example, to evaluate erosion, nutrient loading rates, chemical mass, heat content and thermal stability, biological productivity and effectiveness of growth, and many other structural and functional components of the ecosystem. Management techniques, such as the loading capacity for effluents and the selective removal of undesirable components of the biota, are also heavily dependent on a detailed knowledge of the morphometry and water retention times in freshwater ecosystems.

Accurate hydropraphic maps of lakes and streams are rarely available in sufficient detail for the limnologist. It is a characteristic feature that the morphometry of lakes and streams changes with time, so even if bathymetric (i.e., depth contour) maps are available from governmental or other sources, their accuracy should be checked carefully. It is essential, therefore, that the rudiments of the construction of bathymetric maps and the computation of morphometric parameters be understood.