11:30 AM - 11:45 AM
[AHW24-10] Hydro-Ecological Assessment for Sustainable Management of Muthupet Estuary in the Coramandel Coast of Tamil Nadu, India
Keywords:Hydro-ecology, Mangroves , Estuary
Relevance and Background
Most of the tropical estuaries are facing salinity intrusion and the problem is enhanced with the dwindling flows from the upstream drainage basins. This has created several threats to the ecosystem, biodiversity and the livelihood of the people in and around these water bodies. In the tropical zone, the mangroves in the estuarine belt are affected by the fluctuations in freshwater flows. In this context, an attempt has been made to understand the salinity levels to be maintained in the estuaries for the healthy growth of mangroves and the measures to be taken to maintain the required salinity levels in a particular estuary, namely Muthupet Estuary on the Coramandel coast of India.
Methodology
Several observations were made in the estuary to find out the freshwater flows to be maintained for different salinity levels in the estuary. Based on the detailed observations, curves were plotted relating salinity levels with distance from the freshwater flows. Based on that the rate of freshwater flows for maintaining a salinity level of 17 ppt in the estuary was estimated. For field observations boats were used. Water samples were collected from different locations and depths using water samplers and the salinity was determined using electrical conductivity meters. The data on freshwater flow were available from the gauging stations of the Public Works Department, Tamil Nadu. The surface water levels reflected the tidal effect also. The area under mangrove cultivation was mapped by field surveys. The satellite data was also made use of for understanding the fluctuations in the areal extent of mangroves.
Results and discussions
Based on a series of studies, it is concluded that a salinity level of 17 ppt is the maximum upper level for the healthy growth of mangroves in the tropical zone, especially the Avicennia species. A correlation between freshwater flow and salinity levels was arrived at and the freshwater flow to be maintained with regard to this particular estuary was computed as 10m3/s for maintaining a salinity level of 17 ppt. The study is expected to help similar ecosystems where high salinity levels are observed in the tropical zone.
Conclusions
The study brought to light that the maximum salinity level possible for healthy growth of mangroves in this tropical zone is somewhere around 17 ppt. The study also brought to light that an established correlation between freshwater flow and salinity level could help in estimating the freshwater flows to be maintained in estuaries.
Most of the tropical estuaries are facing salinity intrusion and the problem is enhanced with the dwindling flows from the upstream drainage basins. This has created several threats to the ecosystem, biodiversity and the livelihood of the people in and around these water bodies. In the tropical zone, the mangroves in the estuarine belt are affected by the fluctuations in freshwater flows. In this context, an attempt has been made to understand the salinity levels to be maintained in the estuaries for the healthy growth of mangroves and the measures to be taken to maintain the required salinity levels in a particular estuary, namely Muthupet Estuary on the Coramandel coast of India.
Methodology
Several observations were made in the estuary to find out the freshwater flows to be maintained for different salinity levels in the estuary. Based on the detailed observations, curves were plotted relating salinity levels with distance from the freshwater flows. Based on that the rate of freshwater flows for maintaining a salinity level of 17 ppt in the estuary was estimated. For field observations boats were used. Water samples were collected from different locations and depths using water samplers and the salinity was determined using electrical conductivity meters. The data on freshwater flow were available from the gauging stations of the Public Works Department, Tamil Nadu. The surface water levels reflected the tidal effect also. The area under mangrove cultivation was mapped by field surveys. The satellite data was also made use of for understanding the fluctuations in the areal extent of mangroves.
Results and discussions
Based on a series of studies, it is concluded that a salinity level of 17 ppt is the maximum upper level for the healthy growth of mangroves in the tropical zone, especially the Avicennia species. A correlation between freshwater flow and salinity levels was arrived at and the freshwater flow to be maintained with regard to this particular estuary was computed as 10m3/s for maintaining a salinity level of 17 ppt. The study is expected to help similar ecosystems where high salinity levels are observed in the tropical zone.
Conclusions
The study brought to light that the maximum salinity level possible for healthy growth of mangroves in this tropical zone is somewhere around 17 ppt. The study also brought to light that an established correlation between freshwater flow and salinity level could help in estimating the freshwater flows to be maintained in estuaries.