25 research outputs found
Critically Vulnerable Coastal Areas - A Framework for Community Based Resource Management: Vembanad, Kerala 2016
The Sustainable Development Goal
(SDG) 14 emphasizes Conservation
and Sustainable use of the oceans,
seas and marine resources for
sustainable development. Further,
India's National Conservation Strategy
and Policy Statement on Environmental
and Development, 1992 and the
National Environmental Policy, 2006
recognize the importance of multi
stakeholder partnership in
implementation of conservation plans
for sustainable development of natural
resources
Climate Change Adaptation Pathways in Kolkata
Disaster risk management and wider processes of adaptation are too often understood in isolation from development. Kolkata faces increasing heatwaves, flood hazard and everyday waterlogging as a result of climate change but the social and spatial distribution of impacts will likely be mediated by historic and contemporary development decisions. The paper reports on a study that has combined a scenario workshop method and expert interviews to surface the views of risk and resilience planners, academics and urban professionals on the adaptation–development nexus. Kolkata is experiencing rapid and fundamental transition in its governance regimes and economic structures as state-led development gives way to stronger market forces. Planners welcome an opening of urban governance but are worried by the speed of change. Transition in risk governance is observed in a predicted shift from a contemporary orientation where capacity is limited but focused on protecting development gains, to one which also embraces the flexibility of resilience. </jats:p
Both riverine detritus and dissolved nutrients drive lagoon fisheries
The net ecosystem metabolism in lagoons has often been estimated from the net budget of dissolved nutrients. Such is the case of the LOICZ estuarine biogeochemistry nutrient budget model that considers riverine dissolved nutrients, but not riverine detritus. However the neglect of detritus can lead to inconsistencies; for instance, it results in an estimate of 5–10 times more seaward export of nutrients than there is import from rivers in Chilika Lagoon, India. To resolve that discrepancy the UNESCO estuarine ecohydrology model, that considers both dissolved nutrients and detritus, was used and, for Chilika Lagoon, it reproduced successfully the spatial distribution of salinity, dissolved nutrients, phytoplankton and zooplankton as well as the fish yield data. Thus the model suggests that the riverine input of both detritus and dissolved nutrients supports the pelagic food web. The model also reproduces well the observation of decreased fish yield when the mouth of the lagoon was choked in the 1990s, demonstrating the importance of the physics that determine the flushing rate of waterborne matter. Thus, both farming in the watershed by driving the nutrient and detritus inputs to the lagoon, and dredging and engineering management of the mouth by controlling the flushing rate of the lagoon, have a major influence on fish stocks in the lagoon
Source-sink inventory of greenhouse gases from Indian mangroves: a review
1013-1025Present study inventorises quantitative evaluation of
greenhouse gas (GHG) emissions from various mangrove ecosystems distributed
along the Indian coast. Inconsistency in terms of methodological aspects of GHG
flux estimations from Indian mangrove ecosystems along with the variation in
space and time, has been tried to be pointed out in this present paper.
Inventorization of existing resources available from mangrove ecosystems along
the east and west coast of India,
would be useful for estimating the future potential ecosystem capacities for
fluxes of CO2, CH4 and N2O. This
review further confirms the potential role of Indian mangrove waters and
sediments as perinial source for GHGs, whereas the canopy (vegetation)
particularly acts as a CO2 sink
Seagrass and macrophyte mediated CO2 and CH4 dynamics in shallow coastal waters.
Seagrass meadows are among the most important coastal/ marine ecosystems for long-term carbon storage and conditioning of coastal waters. A combined air-water flux of CO2 and CH4 from the seagrass meadows was studied for the first time from Asia's largest brackish-water lagoon, Chilika, India. Ecosystem-based comparisons were carried out during two hydrologically different conditions of dry and wet seasons in the seagrass dominated southern sector (SS); macrophyte-dominated northern sector (NS); the largely un-vegetated central sector (CS) and the tidally active outer channel (OC) of the lagoon. The mean fluxes of CO2 from SS, NS, CS and OC were 9.8, 146.6, 48.4 and 33.0mM m-2d-1, and that of CH4 were 0.12, 0.11, 0.05 and 0.07mM m-2d-1, respectively. The net emissions (in terms of CO2 equivalents), considering the global warming potential of CO2 (GWP: 1) and CH4 (GWP: 28) from seagrass meadows were over 14 times lower compared to the macrophyte-dominated sector of the lagoon. Contrasting emissivity characteristics of CO2 and CH4 were observed between macrophytes and seagrass, with the former being a persistent source of CO2. It is inferred that although seagrass meadows act as a weak source of CH4, they could be effective sinks of CO2 if land-based pollution sources are minimized
Stable isotope analysis of Porites coral core from the Andaman Islands
North Atlantic climate variations are reflected in sedimentary records from the northern Indian Ocean in which two basins, the Arabian Sea and the Bay of Bengal, are strongly affected by the monsoon. Contrary to the Bay of Bengal the Arabian Sea plays an important role in the global marine nitrogen cycle. In its mid-water oxygen minimum zone (OMZ) bioavailable fixed nitrogen is reduced to nitrogen gas (NO3- - > N2), whereas oxygen concentrations are slightly above the threshold of nitrate reduction in the OMZ of the Bay of Bengal. A coral colony (Porites lutea) growing south of Port Blair on the Andaman Islands in the Bay of Bengal was studied for its response to changes in the monsoon system and its link to temperature changes in the North Atlantic Ocean, between 1975 and 2006. Its linear extension rates, d13C and d18O values measured within the coral skeleton reveal a strong seasonality, which seems to be caused by the monsoon-driven reversal of the surface ocean circulation. The sampling site appears to be influenced by low salinity Bay of Bengal Water during the NE monsoon (boreal winter) and by the high salinity Arabian Sea Water during the SW monsoon in summer. The high salinity Arabian Sea Water circulates along with the Summer Monsoon Current (S-MC) from the Arabia Sea into the Bay of Bengal. Decreasing d18O and reconstructed salinity values correlate to the increasing SSTs in the North Atlantic Ocean indicating a reduced influence of the S-MC at the sampling site in the course of northern hemispheric warming. During such periods oxygen-depletion became stronger in the OMZ of the Arabian Sea as indicated by the sedimentary records. A reduced propagation of oxygen-depleted high salinity Arabian Sea Water into the Bay of Bengal could be a mechanism maintaining oxygen concentration above the threshold of nitrate reduction in the OMZ of the Bay of Bengal in times of global warming
First record of the heart urchin Metalia persica (Mortensen, 1940) (Spatangoida: Brissidae) from the Chennai coast, India
Kanagaraj, Chamundeeswari, Mooi, Rich, Kumar, Deepak Samuel Vijay, Premachandran, Hrishikesh, Rajendran, Abhilash Kottarathil, Rethinavelu, Sankar, Ramachandran, Purvaja, Ramachandran, Ramesh (2019): First record of the heart urchin Metalia persica (Mortensen, 1940) (Spatangoida: Brissidae) from the Chennai coast, India. Zootaxa 4624 (2): 296-300, DOI: 10.11646/zootaxa.4624.2.1
Limited distribution of Devil snail <em>Faunus ater</em> (Linnaeus, 1758) in tropical mangrove habitats of India
2002-2007Our study reports the occurrence of devil snail, Faunus ater from a mangrove habitat of Sindhudurg District, Maharashtra, India. The density of the aggregation of devil snail in the study area ranged from 100 to 640/m2. Out of the 46 mangrove patches surveyed, this species was observed only in Aadbandar. Significantly, this study provides baseline information regarding the abundance and distribution of devil snail from the Indian subcontinent
Wetlands of Small Island Nations in South Asia vis-à-vis the Mainland and Island Groups in India: Status and Conservation Strategies
The wetlands of small island nations in South Asia such as Sri Lanka and the
Maldives are compared with that of India with respect to their status, biodiversity,
threats and conservation measures. Sri Lanka has diverse coastal habitats,
which are known to support fishes (1800 species), marine turtles (5 species),
marine mammals (38 species), corals (183 species), mangroves (40 species),
birds (100 species), reptiles (33 species) and seagrasses (10 species). The
Maldives boasts one of the world’s richest marine biodiversity comprising 250
species of corals, over 1200 of reef fishes, 200 species of sponges, over 1000
species of crustaceans and over 100 species of echinoderms. Marine biodiversity
of India comprises 12,913 species, of which more than 5800 species are
reported from Andaman and Nicobar Islands. Marine biodiversity of
Lakshadweep islands is represented by corals (172 species), fishes (396),
sponges (95), molluscs (260), echinoderms (84), crustaceans (80), turtles (04),birds (142), marine mammals (6), seagrasses (07) and mangroves (03). The
major threats to these wetlands of South Asian countries are climate change,
extreme events like tsunami, coastal erosion, population pressure, habitat
destruction and over-exploitation. The chapter emphasises the need for adopting
frontier tools for biodiversity documentation and innovative strategies for their
conservation
An updated checklist of shrimps on the Indian coast
This study reports an updated checklist of marine shrimps found along the Indian coast, including the Lakshadweep and the Andaman & Nicobar Islands. A total of 364 species classified under 128 genera belonging to the order Decapoda is reported, thus adding 27 species to the existing checklist of 337 species. Marine shrimps are classified under two suborders of the order Decapoda, viz., Dendrobranchiata and Pleocyemata, and the two suborders account for 155 (42.6 %) and 209 species (57.4 %) of these 364 species, respectively. Pleocyemata is represented by three infraorders, viz., Axiidea, Caridea and Stenopodidea, while Caridea has a maximum of 199 reported species. Among the 12 superfamilies, Penaeoidea contributed to 38.13% (135 species) followed by Paleaemonidea with 18.07% (64 species). All other superfamilies were found to contribute less than 12%. Superfamilies, Bresilloidea and Psalidopodoidea had only single species representatives (0.28% each). The final list was compiled after reviewing all existing literature including monographs, catalogues, checklists, websites and fishery reports. The scientific names were validated with the World Register of Marine Species (WoRMS) database. A total of 25 issues were identified from the previous checklist out of which 19 species have been updated with the correct, accepted names and six species have been removed from the previous list.</p