Studies on the benthose of the mud bank regions of the Kerala coast

There is very little information on the subtidal bottom fauna of the shelf regions in the seas around India. What little is known is restricted to macro benthos. The paucity of the work on bottom fauna and the importance of mud banks in the fishery of the South West Coast of India has initiated the present study. Attempts have been made to obtain a picture of the bottom fauna of a mud bank region of the Kerala Coast. The difficulties involved in the sampling and analysis, especially the availability of a suitable vessel during the S.W. Monsoon, resulted in the work being restricted mainly to the Narakal mud bank region 6 Km. north of Cochin Detailed sampling is conducted using grab, dredge and to a small extent beam trawl, to assess the qualitative and quantitative nature of the macro benthos. Important species contributing to the fauna are identified and the standing crop estimated for different seasons. The meiobenthos was studied using core samples taken from the grab. Animals were identified to the major taxa. Standing crop of meiobenthos and the quantitative importance of different groups were also studied. The data collected have been interpreted and discussed. As an understanding of the physico-chemical aspects of the environment is essential in order to obtain a true picture of the benthos, attempts were made in this direction. Environmental parameters such as temperature of the sediment, salinity, temperature, and dissolved oxygen in the overlying water were studied .during the period of benthos investigation. Monthly observations on the dissolved inorganic and organic phosphorus in the area of investigation have been made. The physico-chemical nature of the sediment was also studied. Influence of these ecological variables on the bottom fauna is discussed.

Impact of Western Ghats Orography on the Weather and Climate over Southern Peninsular India-A Mesoscale Modelling Study

The thesis gives a general introduction about the topic include India, the spatial and temporal variation of the surface meteorological parameters are dealt in detail. The general pattern of the winds over the region in different seasons and the generation and movements of the thermally and dynamically originated local wind systems of Western Ghats region has been studied. The modification of the prevailing winds over region by the Palghat Gap and its effect on the mouth regions pf the gap is analysed in great depth. The thesis gives the information of climatic elements of the mountain region such as energy budgets, rainfall studies, evaporation and condensation and the variation in the heat fluxes over the region. The impact of orography is studied in a different approach. The type of hypothetical study gives more insight into the control of mountain on the distribution of meteorological parameter over the study region and helps to quantify the impact of the mountain in varying the weather climate of region. The detailed study of the hydro-meteorological aspects of the main river basins of the region also should be included to the climatic studies for the total understanding of the weather and climate over the region.

Studies on rainfall variability and the influence of orography and land use on the climate of Peninsular India

The present study helped to understand the trend in rainfall patterns at smaller spatial scales and the large regional differences in the variability of rainfall. The effect of land use and orography on the diurnal variability is also understood. But a better understanding on the long term variation in rainfall is possible by using a longer dataset,which may provide insight into the rainfall variation over country during the past century. The basic mechanism behind the interannual rainfall variability would be possible with numerical studies using coupled Ocean-Atmosphere models. The regional difference in the active-break conditions points to the significance of regional studies than considering India as a single unit. The underlying dynamics of diurnal variability need to be studied by making use of a high resolution model as the present study could not simulate the local onshore circulation. Also the land use modification in this study, selected a region, which is surrounded by crop land. This implies the high possibility for the conversion of the remaining region to agricultural land. Therefore the study is useful than considering idealized conditions, but the adverse effect of irrigated crop is more than non-irrigated crop. Therefore, such studies would help to understand the climate changes occurred in the recent period. The large accumulation of rainfall between 300-600 m height of western Ghats has been found but the reason behind this need to be studied, which is possible by utilizing datasets that would better represent the orography and landuse over the region in high resolution model. Similarly a detailed analysis is needed to clearly identify the causative relations of the predictors identified with the predictant and the physical reasons behind them. New approaches that include nonlinear relationships and dynamical variables from model simulations can be included in the existing statistical models to improve the skill of the models. Also the statistical models for the forecasts of monsoon have to be continually updated.