Résumé/Abstract The eastern coast of India harbours a number of mangrove forests, which are now u... more Résumé/Abstract The eastern coast of India harbours a number of mangrove forests, which are now under stress due to climate change-induced sea level rise; sea level is steadily increasing at a rate of 9―12 cm year-1. Current projections for sea level rise are about 0.4―0.9 m; this will have a devastating effect on Indian mangroves. There is significant variability in local C, N and P chemistry, and the accumulation and export of these nutrients are due to changes in land use patterns and rising sea level. Seasonal variations control ...
This article reports the greenhouse gas emissions of anthropogenic origin by sources and removals... more This article reports the greenhouse gas emissions of anthropogenic origin by sources and removals by sinks of India for 2007 prepared under the aegis of the Indian Network for Climate Change Assessment (INCCA) (note 1). The emission profile includes carbon dioxide (CO(2)), methane and nitrous oxide. It also includes the estimates of hydrofluorocarbons, perfluorocarbons and sulphur hexafluoride at the national level from various sectors, viz, energy, industrial process and product use, agriculture, land-use, land-use change and forestry (LULUCF), and waste. In 2007, emissions were of the order of 2008.67 Tg (note 2) of CO(2) equivalents without emissions from the LULUCF sector. Whereas with LULUCF the emissions were about 1831.65 Tg CO(2) equivalents. The energy sector accounted for 69% of the total emissions, the agriculture sector contributed 19% of the emissions, 9% of the emissions was from the industrial processes and product use, and only 3% of the emissions was attributable to...
The nutrient and dissolved metal concentration in Bhitarkanika mangrove system, Orissa, east coas... more The nutrient and dissolved metal concentration in Bhitarkanika mangrove system, Orissa, east coast of India had been examined. Surface water samples were collected from the different regions of mangrove-estuarine complex during the post monsoon season. There was distinct variation in chemical constituents of water among the estuarine, mangrove and bay region. Physicochemical parameters like pH, EC and TDS and nutrients like NO3, PO4 varied significantly among three sectors. The cations like K + , Ca 2+ , NH4 and anions like SO4 2- , HCO - 3, SiO2 didn’t showed any significant variation. There is high concentration of dissolved metal in this mangrove system. The above fact will reveal that mangrove is facing severe threat due to industrial pollution. The metals, Cu, Zn and Co showed higher affinity, while Pb and Cr also result in strong coupling with each other.
Abstract The diverse habitat of the mangrove ecosystems all over the globe are under continuous t... more Abstract The diverse habitat of the mangrove ecosystems all over the globe are under continuous threat of conversion for immediate and/or short-term economic benefits. Nonetheless, the emission of climatically relevant greenhouse gases increases with the disturbance of the mangrove sediment −this might undermine the credible reservoir of carbon within the sediment. This article attempts to estimate the environmental (carbon emission) and economic consequences of converting mangrove to cropland (especially rice paddy) based on field-scale study at three different sites (Khola, Gupti and Damra) within the Bhitarkanika mangrove for two consecutive years. The study suggests that the cumulative methane (CH4) emission was significantly higher from the rice paddy (211.3 kg ha−1) compared to the mangrove sediment (50.8 kg ha−1), while the average nitrous oxide (N2O) emission was significantly higher from the later (2.1 kg ha−1). Multivariate statistical analysis suggests that the land use was the prime controlling factor for variation in CH4 and N2O emission. Total carbon equivalent emission (CEETOT) from the rice paddy was significantly higher than mangrove during the study period. The study suggests that the economic value of the mangrove ecosystem was several folds higher than that of the rice paddy. The CEETOT of the Bhitarkanika mangrove has increased approximately 212 Gg over last few decades due to the conversion of the mangrove area to the rice paddy. Such studies are imperative in developing effective regional climate change adaptation strategies. The study advocates urgent need to educate and aware people about the benefits of the mangrove compared to the cropland.
Abstract We have studied the seasonal and tidal variation of methane (CH 4 ) and nitrous oxide (N... more Abstract We have studied the seasonal and tidal variation of methane (CH 4 ) and nitrous oxide (N 2 O) emission from the intertidal sediment of Bhitarkanika mangrove in the east coast of India. Seasonal variability study was conducted at five sites (three replicate of each site) inside the core area of the national park during three different seasons (summer, monsoon and winter) whereas tidal variation was studied at three different sites outside the core area during monsoon and winter season. Both CH 4 and N 2 O emission from the intertidal sediment were significantly higher under the low tide condition during the winter season. During the study period CH 4 emission from five different sites was ranged between 0.08 and 2.30 mg m −2 h −1 and the N 2 O emission was ranged between 9.0 and 187.58 μg m −2 h −1 . Average seasonal N 2 O emission (μg m −2 h −1 ) from five different sites followed the order: winter (115.60 ± 21.90) > summer (45.29 ± 7.78) > monsoon (16.98 ± 2.54). CH 4 and N 2 O emission was also recorded significantly higher during the winter season over the tidal cycle of three sampling locations. The CH 4 emission was negatively correlated with sediment salinity (r = −0.91, P 4 –2 (r = −0.89, P 2 O emission was positively correlated with sediment salinity (r = 0.48) and NO 3 − –N (r = 0.88, P 2 O emission with the sediment NO 3 − –N indicates possible influence of upstream anthropogenic activities on N 2 O emission from the mangrove sediment. In general, methylamine utilizing methanogen and denitrifying bacterial population was significantly higher during winter season in the mangrove sediment. The study concludes that the CH 4 and N 2 O emission from the sediment at different sites during different seasons are influenced by allochthonous carbon and nitrogenous materials.
The Pichavaram mangrove ecosystem is located between the Vellar and Coleroon Estuaries in south-e... more The Pichavaram mangrove ecosystem is located between the Vellar and Coleroon Estuaries in south-eastern India. To document the spatial-depth-based variabilities in organic matter (OM) input and cycling, five sediment cores were collected. A comparative study was carried out of grain-size composition, pore water salinity, dissolved organic C (DOC), loss-on-ignition (LOI), elemental ratios (C/N and H/C), pigments (Chl a, Chl b, and total carotenoids), and humification indices. Sand is the major fraction in these cores ranging from 60% to 99% followed by silt and clay; cores from the estuarine margin have high sand content. In mangrove forests, pore-water DOC concentrations are high (32 ± 14 mg L), whereas salinity levels are low (50 ± 5.5‰). Likewise, LOI, organic C and N, and pigment concentrations are high in mangroves. OM is mainly derived from upstream terrestrial matter and/or mangrove litter, and marine OM. The humification indices do not vary significantly with depth because of...
Abstract Coastal areas have been recognized as one of the major contributors to the atmospheric f... more Abstract Coastal areas have been recognized as one of the major contributors to the atmospheric flux of greenhouse gases at local, regional and global scales. Mangrove forests are constantly affected from the anthropogenic activities mainly intensive cultivation. In a study in the tropical mangrove areas of Bhitarkanika sancturary, NE Orissa and adjoining paddy fields, a comparative estimation of emission rates of two climatologically important greenhouse gases, viz. CH4 and N2O were measured for monsoon and post-monsoon ...
Phosphorus (P) is an essential nutrient which plays a key role in global biogeochemical cycles. C... more Phosphorus (P) is an essential nutrient which plays a key role in global biogeochemical cycles. Coastal ecosystems such as mangroves are an important sink which can trap significant quantities of P. The phosphorus as such deposited in sediments is not available to the organisms, but is converted to bioavailable forms as dissolved orthophosphate through a series of biogeochemical reactions. Several studies on phosphorus reservoirs, transport rates (fluxes) and residence times are reported from different ecosystems across the world. In the present article, an effort has been made to compile and review the scientific research carried out on phosphorus biogeochemistry in the mangroves of India.
Nitrogen is an essential element for a variety of biological and chemical processes; both at micr... more Nitrogen is an essential element for a variety of biological and chemical processes; both at micro (organism) level as well as macro (ecosystem) level. The behaviour of nitrogen in mangrove environment depends on the ion exchange capacity, redox conditions, organic matter and clay content of the sediment. Marine coastal waters often receive high loads of nutrients (namely nitrogen and phosphorus due to human activities that may lead to serious eutrophication problems.
The present article provides a brief overview of Indian Network for Climate Change Assessment (IN... more The present article provides a brief overview of Indian Network for Climate Change Assessment (INCCA) which is a new initiative of the Ministry of Environment and Forests. It has been visualized as a network of institutions countrywide and is designed to undertake a range of activities in the area of climate change, eg science, impacts, vulnerability, mitigation and adaptation. Under the aegis of INCCA, two assessments, viz.
This article reports the greenhouse gas emissions of anthropogenic origin by sources and removals... more This article reports the greenhouse gas emissions of anthropogenic origin by sources and removals by sinks of India for 2007 prepared under the aegis of the Indian Network for Climate Change Assessment (INCCA)(note 1). The emission profile includes carbon dioxide (CO (2)), methane and nitrous oxide.
Résumé/Abstract The eastern coast of India harbours a number of mangrove forests, which are now u... more Résumé/Abstract The eastern coast of India harbours a number of mangrove forests, which are now under stress due to climate change-induced sea level rise; sea level is steadily increasing at a rate of 9―12 cm year-1. Current projections for sea level rise are about 0.4―0.9 m; this will have a devastating effect on Indian mangroves. There is significant variability in local C, N and P chemistry, and the accumulation and export of these nutrients are due to changes in land use patterns and rising sea level. Seasonal variations control ...
This article reports the greenhouse gas emissions of anthropogenic origin by sources and removals... more This article reports the greenhouse gas emissions of anthropogenic origin by sources and removals by sinks of India for 2007 prepared under the aegis of the Indian Network for Climate Change Assessment (INCCA) (note 1). The emission profile includes carbon dioxide (CO(2)), methane and nitrous oxide. It also includes the estimates of hydrofluorocarbons, perfluorocarbons and sulphur hexafluoride at the national level from various sectors, viz, energy, industrial process and product use, agriculture, land-use, land-use change and forestry (LULUCF), and waste. In 2007, emissions were of the order of 2008.67 Tg (note 2) of CO(2) equivalents without emissions from the LULUCF sector. Whereas with LULUCF the emissions were about 1831.65 Tg CO(2) equivalents. The energy sector accounted for 69% of the total emissions, the agriculture sector contributed 19% of the emissions, 9% of the emissions was from the industrial processes and product use, and only 3% of the emissions was attributable to...
The nutrient and dissolved metal concentration in Bhitarkanika mangrove system, Orissa, east coas... more The nutrient and dissolved metal concentration in Bhitarkanika mangrove system, Orissa, east coast of India had been examined. Surface water samples were collected from the different regions of mangrove-estuarine complex during the post monsoon season. There was distinct variation in chemical constituents of water among the estuarine, mangrove and bay region. Physicochemical parameters like pH, EC and TDS and nutrients like NO3, PO4 varied significantly among three sectors. The cations like K + , Ca 2+ , NH4 and anions like SO4 2- , HCO - 3, SiO2 didn’t showed any significant variation. There is high concentration of dissolved metal in this mangrove system. The above fact will reveal that mangrove is facing severe threat due to industrial pollution. The metals, Cu, Zn and Co showed higher affinity, while Pb and Cr also result in strong coupling with each other.
Abstract The diverse habitat of the mangrove ecosystems all over the globe are under continuous t... more Abstract The diverse habitat of the mangrove ecosystems all over the globe are under continuous threat of conversion for immediate and/or short-term economic benefits. Nonetheless, the emission of climatically relevant greenhouse gases increases with the disturbance of the mangrove sediment −this might undermine the credible reservoir of carbon within the sediment. This article attempts to estimate the environmental (carbon emission) and economic consequences of converting mangrove to cropland (especially rice paddy) based on field-scale study at three different sites (Khola, Gupti and Damra) within the Bhitarkanika mangrove for two consecutive years. The study suggests that the cumulative methane (CH4) emission was significantly higher from the rice paddy (211.3 kg ha−1) compared to the mangrove sediment (50.8 kg ha−1), while the average nitrous oxide (N2O) emission was significantly higher from the later (2.1 kg ha−1). Multivariate statistical analysis suggests that the land use was the prime controlling factor for variation in CH4 and N2O emission. Total carbon equivalent emission (CEETOT) from the rice paddy was significantly higher than mangrove during the study period. The study suggests that the economic value of the mangrove ecosystem was several folds higher than that of the rice paddy. The CEETOT of the Bhitarkanika mangrove has increased approximately 212 Gg over last few decades due to the conversion of the mangrove area to the rice paddy. Such studies are imperative in developing effective regional climate change adaptation strategies. The study advocates urgent need to educate and aware people about the benefits of the mangrove compared to the cropland.
Abstract We have studied the seasonal and tidal variation of methane (CH 4 ) and nitrous oxide (N... more Abstract We have studied the seasonal and tidal variation of methane (CH 4 ) and nitrous oxide (N 2 O) emission from the intertidal sediment of Bhitarkanika mangrove in the east coast of India. Seasonal variability study was conducted at five sites (three replicate of each site) inside the core area of the national park during three different seasons (summer, monsoon and winter) whereas tidal variation was studied at three different sites outside the core area during monsoon and winter season. Both CH 4 and N 2 O emission from the intertidal sediment were significantly higher under the low tide condition during the winter season. During the study period CH 4 emission from five different sites was ranged between 0.08 and 2.30 mg m −2 h −1 and the N 2 O emission was ranged between 9.0 and 187.58 μg m −2 h −1 . Average seasonal N 2 O emission (μg m −2 h −1 ) from five different sites followed the order: winter (115.60 ± 21.90) > summer (45.29 ± 7.78) > monsoon (16.98 ± 2.54). CH 4 and N 2 O emission was also recorded significantly higher during the winter season over the tidal cycle of three sampling locations. The CH 4 emission was negatively correlated with sediment salinity (r = −0.91, P 4 –2 (r = −0.89, P 2 O emission was positively correlated with sediment salinity (r = 0.48) and NO 3 − –N (r = 0.88, P 2 O emission with the sediment NO 3 − –N indicates possible influence of upstream anthropogenic activities on N 2 O emission from the mangrove sediment. In general, methylamine utilizing methanogen and denitrifying bacterial population was significantly higher during winter season in the mangrove sediment. The study concludes that the CH 4 and N 2 O emission from the sediment at different sites during different seasons are influenced by allochthonous carbon and nitrogenous materials.
The Pichavaram mangrove ecosystem is located between the Vellar and Coleroon Estuaries in south-e... more The Pichavaram mangrove ecosystem is located between the Vellar and Coleroon Estuaries in south-eastern India. To document the spatial-depth-based variabilities in organic matter (OM) input and cycling, five sediment cores were collected. A comparative study was carried out of grain-size composition, pore water salinity, dissolved organic C (DOC), loss-on-ignition (LOI), elemental ratios (C/N and H/C), pigments (Chl a, Chl b, and total carotenoids), and humification indices. Sand is the major fraction in these cores ranging from 60% to 99% followed by silt and clay; cores from the estuarine margin have high sand content. In mangrove forests, pore-water DOC concentrations are high (32 ± 14 mg L), whereas salinity levels are low (50 ± 5.5‰). Likewise, LOI, organic C and N, and pigment concentrations are high in mangroves. OM is mainly derived from upstream terrestrial matter and/or mangrove litter, and marine OM. The humification indices do not vary significantly with depth because of...
Abstract Coastal areas have been recognized as one of the major contributors to the atmospheric f... more Abstract Coastal areas have been recognized as one of the major contributors to the atmospheric flux of greenhouse gases at local, regional and global scales. Mangrove forests are constantly affected from the anthropogenic activities mainly intensive cultivation. In a study in the tropical mangrove areas of Bhitarkanika sancturary, NE Orissa and adjoining paddy fields, a comparative estimation of emission rates of two climatologically important greenhouse gases, viz. CH4 and N2O were measured for monsoon and post-monsoon ...
Phosphorus (P) is an essential nutrient which plays a key role in global biogeochemical cycles. C... more Phosphorus (P) is an essential nutrient which plays a key role in global biogeochemical cycles. Coastal ecosystems such as mangroves are an important sink which can trap significant quantities of P. The phosphorus as such deposited in sediments is not available to the organisms, but is converted to bioavailable forms as dissolved orthophosphate through a series of biogeochemical reactions. Several studies on phosphorus reservoirs, transport rates (fluxes) and residence times are reported from different ecosystems across the world. In the present article, an effort has been made to compile and review the scientific research carried out on phosphorus biogeochemistry in the mangroves of India.
Nitrogen is an essential element for a variety of biological and chemical processes; both at micr... more Nitrogen is an essential element for a variety of biological and chemical processes; both at micro (organism) level as well as macro (ecosystem) level. The behaviour of nitrogen in mangrove environment depends on the ion exchange capacity, redox conditions, organic matter and clay content of the sediment. Marine coastal waters often receive high loads of nutrients (namely nitrogen and phosphorus due to human activities that may lead to serious eutrophication problems.
The present article provides a brief overview of Indian Network for Climate Change Assessment (IN... more The present article provides a brief overview of Indian Network for Climate Change Assessment (INCCA) which is a new initiative of the Ministry of Environment and Forests. It has been visualized as a network of institutions countrywide and is designed to undertake a range of activities in the area of climate change, eg science, impacts, vulnerability, mitigation and adaptation. Under the aegis of INCCA, two assessments, viz.
This article reports the greenhouse gas emissions of anthropogenic origin by sources and removals... more This article reports the greenhouse gas emissions of anthropogenic origin by sources and removals by sinks of India for 2007 prepared under the aegis of the Indian Network for Climate Change Assessment (INCCA)(note 1). The emission profile includes carbon dioxide (CO (2)), methane and nitrous oxide.
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