EUTROPHICATION MODELLING OF NAINITAL LAKE

Abstract

A deterministic, two-layer Phytoplankton model was taken for the study of eutrophication in Nainital lake and a computer programme was developed for it. A priori sensitivity analysis was done and with the inferences drawn from it, some suitable changes were made it the model. This model was then calibrated to an extensive set of field data of 1977-78. A submodel [1] was used to estimate the nutrient loadings to the lake from the catchment. An actual field study programme was taken up in two phases, one in Sept.'87 and another in Dec.'87, and the lake water was tested for various relevant water quality parameters. In collection of samples and their testing in laboratory and field itself, procedures prescribed by Standard Methods for Examination of Water and Wastewater", were followed. Water temperatures were recorded with a' Min-Max temperature thermometer (in Sept.'87) and with a digital temperature probe (in Dec.'87). Intensity of solar radiations at various water depths was measured by a digital lux meter. Dissolved oxygen of the water samples from various depths was fixed and the titrations were done in the field itself.