Factors affecting marine algae diversity and distribution along the Indian coastal region
Marine algae are primitive non-flowering photosynthetic plants inhabiting in seas and oceans that occupy 71% of the globe and they are natural renewable resources. They formed part of human life from time immemorial as food, besides their used as feed, fodder and manure. Marine algae are key space occupiers of rocky shores and interact with other organisms and hence play a key role in overall coastal biodiversity. They are found on rocks in the intertidal zone as a giant underwater forest. Marine algae grow abundantly along the Indian coastline particularly in rocky shore regions. The diversity and distribution of marine macro algal resources of Indian waters are affected since early 1970s due to over exploitation, sediment deposition and discharge of effluents, changes in the environmental factors, water temperature, light intensity, tidal waves, cyclones and consequence of bottom trawl fishing. As a result, there is decrease in algal production in Gulf of Mannar, Andhra coast and Kerala coast. On the other hand, there is rising demand for the phycocolloids viz. agar, algin, carrageenan and others. In this context there is an urgent need for conservation and better exploitation of the resources. Regulation of exploitation, control of pollution by domestic and industrial effluents, conducting algal culture are proposed as measures to overcome the damage to natural algal stocks to enable conservation and sustained production.