The total benthic macrofauna consisting of 62 species in 5 groups,viz. crustaceans(18),gastropods(17),bivalves(16),polychaetes(9) and fishes(2),was recorded in western Kachchh mangroves near Gujarat. The population de...The total benthic macrofauna consisting of 62 species in 5 groups,viz. crustaceans(18),gastropods(17),bivalves(16),polychaetes(9) and fishes(2),was recorded in western Kachchh mangroves near Gujarat. The population densities of benthic macro-fauna ranged from 424 to 2393 ind.m-2,the diversity ranged from 1.84 to 2.45 bits ind.-1,the richness varied between 0.82 and 0.98,and the evenness varied between 0.64 and 0.81. Two maximum diversity values were recorded during winter and summer. The salin-ity ranged from 34 to 44,temperature varied between 17 and 37 ℃,and the acidity ranged from 7 to 8.9.展开更多
The finfish and shellfish resources were assessed quantitatively and qualitatively in regard to their abundance in creek waters at three sites within a period of two years, fi＇om January 1999 to December 2000, in the...The finfish and shellfish resources were assessed quantitatively and qualitatively in regard to their abundance in creek waters at three sites within a period of two years, fi＇om January 1999 to December 2000, in the western mangrove areas of Kachchh. The catch rate varied from 0.69 to 6.99kg·h^-1. It was low during monsoon （July to October）, which could be due to the freshwater-flow-induced salinity reduction in all the sites. Among 38 species recorded, 5 were shellfish and 33 were finfish. The spawning period of fishes was found to be during summer and early monsoon period （May to August）. Surface water temperatures varied from 17℃ to 37 ℃. Salinity values varied from 34 to 44 and the pH ranged between 7 and 8.9. Variation in dissolved oxygen content was from 3.42 to 5.85 mL L^-1. The high fishery densities in these semi arid mangrove creek areas were recorded during monsoon and early winter season.展开更多
The results of an investigation carried out during June 2005 to May 2007 on bloom-forming phytoplankton species composition and abundance in the Parangipettai and Coleroon coastal waters （Southeast coast of India） a...The results of an investigation carried out during June 2005 to May 2007 on bloom-forming phytoplankton species composition and abundance in the Parangipettai and Coleroon coastal waters （Southeast coast of India） are reported. Air and surface water temperatures （℃） varied from 25.1 to 30.1 and 24.5 to 28.5, respectively, in the former waters and from 25.5 to 31.2 and 25.0 to 29.3 in the latter waters. The respective salinities varied from 6.0 to 28.5 and 5.0 to 33.1 and the respective pH ranged between 7.0 and 8.3 and 7.2 and 8.3. Correspondingly, the dissolved oxygen content varied from 3.1 to 7.5 and 3.1 to 7.9 mgL1 while the light extinction coefficient （LEC） values ranged between 3.1 and 10.1 and 1.8 and 11.0. The content ranges of inorganic nutrients, i.e., nitrate, nitrite, phosphate and silicate （μmolL^-1）, in the Parangipettai and Coleroon coastal waters were： 6.5- 27.0; 1.0- 8.9; 0.1-3.0 and 15.0 -140 and 10.1-23.4; 1.2-8.9; 0.2-3.1 and 55-125 respectively. The chlorophyll α contents in both waters ranged from 2.0-7.5 μgL^-1. Presently, 124 phytoplankton species representing different classes were recorded in the Coleroon coast, viz, Bacillariophyceae （77）; Dinophyceae （19）; Cyanophyceae （15）; Chlorophyceae （10） and Chrysophyceae （3）, whereas 117 phytoplankton species were recorded in the Parangipettai coast, viz, Bacillariophyceae （66）; Dinophyceae （22）; Cyanophyceae （19）; Chlorophyceae （7） and Chrysophyceae （3）. The phytoplankton cell abundance in the Parangipettai and Coleroon coastal waters varied from 290 to 111662 and 140 to 132 757 cells L^-1, respectively, with peak diversity （3.38 and 3.52 bits indl.） recorded in summer. The maximum abundance occurred in summer coinciding with the stable hydrographical conditions. The seasonal distribution and abundance of phytoplankton are discussed in relation to hydrographical parameters. Totally 31 and 24 species of phytoplankton were found to be bloom-forming in the Parangipettai and Coleroon coastal waters, respectively. Presently Trichodesmium bloom was also observed, which appeared at the 10 fathom level of the coastal water and quickly spread to the marine zone of the Vellar estuary and near the mouth region of the mangrove waters. The Parangipettai and Coleroon coastal waters are subject to long term fluctuations in physico-chemical conditions depending upon the seasonal tidal range and freshwater influx, resulting in a continuous exchange of organic, inorganic, plant and animal matters.展开更多
The Gulf of Kachchh in western India, with its arid climate, large semi-diurnal tidal amplitudes, negative water balance and near-pristine water quality, is being extensively developed as oil importing bases for econo...The Gulf of Kachchh in western India, with its arid climate, large semi-diurnal tidal amplitudes, negative water balance and near-pristine water quality, is being extensively developed as oil importing bases for economic reasons in connection with its proximity to the oil exporting countries of the Middle East. Besides, new coral rubbings were sighted in Jakhau, north-western Gulf of Kachchh. Dredging in Mandvi of the north Gulf covering 3.5 km2 revealed a similar assortment of live corals with their associated flora and fauna. These pioneering observations demonstrate that there exist live corals of young polyps-colony of Favia sp. belonging to the family Faviidae in the north-western Gulf of Kachchh. The environmental parameters there were carefully recorded as: surface water temperature (℃) varying from 29 to 31.8, salinity (ppt), pH, dissolved oxygen (mgL-1) and total suspended solids (mgL-1) in the ranges of 37- 43.5, 7.7- 8.45, 5.4 - 6.8 and 11- 31, respectively.展开更多
文摘The total benthic macrofauna consisting of 62 species in 5 groups,viz. crustaceans(18),gastropods(17),bivalves(16),polychaetes(9) and fishes(2),was recorded in western Kachchh mangroves near Gujarat. The population densities of benthic macro-fauna ranged from 424 to 2393 ind.m-2,the diversity ranged from 1.84 to 2.45 bits ind.-1,the richness varied between 0.82 and 0.98,and the evenness varied between 0.64 and 0.81. Two maximum diversity values were recorded during winter and summer. The salin-ity ranged from 34 to 44,temperature varied between 17 and 37 ℃,and the acidity ranged from 7 to 8.9.
文摘The finfish and shellfish resources were assessed quantitatively and qualitatively in regard to their abundance in creek waters at three sites within a period of two years, fi＇om January 1999 to December 2000, in the western mangrove areas of Kachchh. The catch rate varied from 0.69 to 6.99kg·h^-1. It was low during monsoon （July to October）, which could be due to the freshwater-flow-induced salinity reduction in all the sites. Among 38 species recorded, 5 were shellfish and 33 were finfish. The spawning period of fishes was found to be during summer and early monsoon period （May to August）. Surface water temperatures varied from 17℃ to 37 ℃. Salinity values varied from 34 to 44 and the pH ranged between 7 and 8.9. Variation in dissolved oxygen content was from 3.42 to 5.85 mL L^-1. The high fishery densities in these semi arid mangrove creek areas were recorded during monsoon and early winter season.
基金the Knowledge Innovation Project of the Chinese Academy of Sciences (KZCX2-YW-QN205 and KZCX2-YW-213-2)the National High Technology Research and Development Program of China (2006A-A09Z179)+1 种基金the National Natural Science Foundation of China (40676089, 40776093)the Major State Basic Research Development Program of China (2006CB-400605 and 2009CB421202) to J Sun
文摘The results of an investigation carried out during June 2005 to May 2007 on bloom-forming phytoplankton species composition and abundance in the Parangipettai and Coleroon coastal waters （Southeast coast of India） are reported. Air and surface water temperatures （℃） varied from 25.1 to 30.1 and 24.5 to 28.5, respectively, in the former waters and from 25.5 to 31.2 and 25.0 to 29.3 in the latter waters. The respective salinities varied from 6.0 to 28.5 and 5.0 to 33.1 and the respective pH ranged between 7.0 and 8.3 and 7.2 and 8.3. Correspondingly, the dissolved oxygen content varied from 3.1 to 7.5 and 3.1 to 7.9 mgL1 while the light extinction coefficient （LEC） values ranged between 3.1 and 10.1 and 1.8 and 11.0. The content ranges of inorganic nutrients, i.e., nitrate, nitrite, phosphate and silicate （μmolL^-1）, in the Parangipettai and Coleroon coastal waters were： 6.5- 27.0; 1.0- 8.9; 0.1-3.0 and 15.0 -140 and 10.1-23.4; 1.2-8.9; 0.2-3.1 and 55-125 respectively. The chlorophyll α contents in both waters ranged from 2.0-7.5 μgL^-1. Presently, 124 phytoplankton species representing different classes were recorded in the Coleroon coast, viz, Bacillariophyceae （77）; Dinophyceae （19）; Cyanophyceae （15）; Chlorophyceae （10） and Chrysophyceae （3）, whereas 117 phytoplankton species were recorded in the Parangipettai coast, viz, Bacillariophyceae （66）; Dinophyceae （22）; Cyanophyceae （19）; Chlorophyceae （7） and Chrysophyceae （3）. The phytoplankton cell abundance in the Parangipettai and Coleroon coastal waters varied from 290 to 111662 and 140 to 132 757 cells L^-1, respectively, with peak diversity （3.38 and 3.52 bits indl.） recorded in summer. The maximum abundance occurred in summer coinciding with the stable hydrographical conditions. The seasonal distribution and abundance of phytoplankton are discussed in relation to hydrographical parameters. Totally 31 and 24 species of phytoplankton were found to be bloom-forming in the Parangipettai and Coleroon coastal waters, respectively. Presently Trichodesmium bloom was also observed, which appeared at the 10 fathom level of the coastal water and quickly spread to the marine zone of the Vellar estuary and near the mouth region of the mangrove waters. The Parangipettai and Coleroon coastal waters are subject to long term fluctuations in physico-chemical conditions depending upon the seasonal tidal range and freshwater influx, resulting in a continuous exchange of organic, inorganic, plant and animal matters.
基金supported by the Chinese Academy of Sciences Research Fellowship for International Young Researchers for M. Rajkumarthe Knowledge Innovation Project of The Chinese Academy of Sciences (KZCX2-YW-QN205, KZCX2-YW-213-2)the National High Technology Research and Development Program of China (2006AA09Z179) for Dr. Jun Sun
文摘The Gulf of Kachchh in western India, with its arid climate, large semi-diurnal tidal amplitudes, negative water balance and near-pristine water quality, is being extensively developed as oil importing bases for economic reasons in connection with its proximity to the oil exporting countries of the Middle East. Besides, new coral rubbings were sighted in Jakhau, north-western Gulf of Kachchh. Dredging in Mandvi of the north Gulf covering 3.5 km2 revealed a similar assortment of live corals with their associated flora and fauna. These pioneering observations demonstrate that there exist live corals of young polyps-colony of Favia sp. belonging to the family Faviidae in the north-western Gulf of Kachchh. The environmental parameters there were carefully recorded as: surface water temperature (℃) varying from 29 to 31.8, salinity (ppt), pH, dissolved oxygen (mgL-1) and total suspended solids (mgL-1) in the ranges of 37- 43.5, 7.7- 8.45, 5.4 - 6.8 and 11- 31, respectively.
