Nutrient Dynamics Controlled by Ground Water Injections

The influence of land-use mosaic among sub-watersheds on coastal processes apply globally to any coastal regions hugged by wetlands and underlain with limestone deposits. The existence of a subterranean flow connecting a tropical backwater to the Arabian Sea through the submerged porous lime shell is indicated from the coastal nutrient distribution. The present investigation represented a nonmud banks period and had fertilization of the coastal water by injection of nutrients by hitherto unknown processes. The high nitrate-N, ammonia concentrations, enriched particulate organic carbon (> 3.5 mg/l) and Chlorophyll a (14.8 mg/m) at a localized coastal region and a band of N/P > 15 funneling out during non-mud bank period gave a clear indication of an ‘external source’ of nitrogenous compounds to the coastal water. The existence of subterraneous channels as the artifacts of porous nature of the lime shell base of the region transporting the nitrogenous compounds cannot be ruled out in the region. The significance of this study is that subterranean flows could redefine the very concept of formation of mud banks, which are presently recognized only as an oceanographic process. Unlike the existing theories, it is argued that formation of mud banks are not entirely forced by coastal oceanographic processes; instead a remote forcing from the land involving a subterranean flow through the submerged lime beds, appears to be an initiative mechanism. The idea that land-use mosaic among sub-watersheds influence coastal processes may apply globally to any coastal regions hugged by wetlands and underlain with limestone deposits .