The present study revealed proliferation of macro-algae modifying coral reef ecosystems in a different manner due to diseases and sedimentations in the Mandapam group of islands in the Gulf of Mannar. Benthic surveys ...The present study revealed proliferation of macro-algae modifying coral reef ecosystems in a different manner due to diseases and sedimentations in the Mandapam group of islands in the Gulf of Mannar. Benthic surveys were conducted with major attack of seven coral reefs diseases with high sedimentation rate, nine species of fleshy macro-algae(Turbinaria ornata, Turbinaria conaides, Caulerpa scalpelliformis, Caulerpa racemosa, Kappaphycus alvarezii, Padina gymnosphora, Sargassum wightii, Ulva reticulata and Calurpa lentillifera) proliferation against major corals life forms(Acropora branching, Acropora digitate, Acropora tabulate, coral massive, coral submassive, coral foliose and coral encrusting). The results confirm that diseased corals most favor to macro-algae growth(15.27%) rather than the sedimentation covered corals(8.24 %). In the degradation of coral life forms, massive corals were more highly damaged(7.05%) than any other forms. Within a short period of time(May to September), coral coverage shrank to 17.4% from 21.9%, macro-algae increased 23.51% and the average sedimentation rate attained 77.52 mg cm^(-2) d^(-1) with persisting coral reef diseases of 17.59%. The Pearson correlation showed that the coral cover decreased with increasing macro-algae growth, which was statistically significant(r =-0.774, n = 100, P < 0.0005). The proliferation of the various macro-algae C. scalpellifrmis, T. ornata, C. racemosa, T. conaides, U. reticulata, S. wightii, K. alvarezii, P. gymnosphora and C. lentillifera increased with percentages of 6.0, 5.8, 5.7, 4.9, 4.2, 3.7, 2.7 and 1.9, respectively. If this trend continues, the next generation of new recruit corals will undoubtedly lead to a phase shift in Gulf of Mannar corals.展开更多
For the first time, sodium metasilicate （SMS） doped ammonium dihydrogen phosphate （ADP） crystal was grown by slow evaporation solution technique. The unit cell parameters of grown crystal were deter- mined by mean...For the first time, sodium metasilicate （SMS） doped ammonium dihydrogen phosphate （ADP） crystal was grown by slow evaporation solution technique. The unit cell parameters of grown crystal were deter- mined by means of single crystal X-ray diffraction technique. The qualitative analysis of SMS doped ADP crystal was carried out using energy dispersive X-ray and Fourier transform infrared analysis. The in- crease in optical transparency of doped ADP crystal was ascertained in the range of 200-900 nm using the UV-visible spectral analysis. The vital optical constants were evaluated using the transmittance data to explore various optical device applications of crystal. The assertive influence of SMS on mechanical and dielectric behavior of ADP crystal was investigated by means of Vickers microhardness analysis and dielectric studies, respectively. The enhancement in second harmonic generation （SHG） efficiency of SMS doped ADP crystal with reference to potassium dihydrogen phosphate （KDP） and ADP was confirmed from Kurtz-Perry SHG test. The Kerr lensing nonlinearity in SMS doped ADP crystal was identified by means of Z-scan analysis and the third order nonlinear optical susceptibility （χ3） was found to be 6.19 × 10-5 esu, which vitalizes its application for laser stabilization systems.展开更多
Crustal deformation and neotectonics are well-understood phenomena that happen almost on every part of the Earth and have some diastrophic effects on the Earth’s surface.To understand these effects,Remote Sensing(RS)...Crustal deformation and neotectonics are well-understood phenomena that happen almost on every part of the Earth and have some diastrophic effects on the Earth’s surface.To understand these effects,Remote Sensing(RS)and(GIS)have sharpened the human ability to learn about the scientiflc reasons for the Earth’s dynamic activities,including active tectonics and surface landform changes in spatially and temporally.展开更多
基金the National Remote Sensing Center, ISRO-Hyderabad for providing financial supports
文摘The present study revealed proliferation of macro-algae modifying coral reef ecosystems in a different manner due to diseases and sedimentations in the Mandapam group of islands in the Gulf of Mannar. Benthic surveys were conducted with major attack of seven coral reefs diseases with high sedimentation rate, nine species of fleshy macro-algae(Turbinaria ornata, Turbinaria conaides, Caulerpa scalpelliformis, Caulerpa racemosa, Kappaphycus alvarezii, Padina gymnosphora, Sargassum wightii, Ulva reticulata and Calurpa lentillifera) proliferation against major corals life forms(Acropora branching, Acropora digitate, Acropora tabulate, coral massive, coral submassive, coral foliose and coral encrusting). The results confirm that diseased corals most favor to macro-algae growth(15.27%) rather than the sedimentation covered corals(8.24 %). In the degradation of coral life forms, massive corals were more highly damaged(7.05%) than any other forms. Within a short period of time(May to September), coral coverage shrank to 17.4% from 21.9%, macro-algae increased 23.51% and the average sedimentation rate attained 77.52 mg cm^(-2) d^(-1) with persisting coral reef diseases of 17.59%. The Pearson correlation showed that the coral cover decreased with increasing macro-algae growth, which was statistically significant(r =-0.774, n = 100, P < 0.0005). The proliferation of the various macro-algae C. scalpellifrmis, T. ornata, C. racemosa, T. conaides, U. reticulata, S. wightii, K. alvarezii, P. gymnosphora and C. lentillifera increased with percentages of 6.0, 5.8, 5.7, 4.9, 4.2, 3.7, 2.7 and 1.9, respectively. If this trend continues, the next generation of new recruit corals will undoubtedly lead to a phase shift in Gulf of Mannar corals.
文摘For the first time, sodium metasilicate （SMS） doped ammonium dihydrogen phosphate （ADP） crystal was grown by slow evaporation solution technique. The unit cell parameters of grown crystal were deter- mined by means of single crystal X-ray diffraction technique. The qualitative analysis of SMS doped ADP crystal was carried out using energy dispersive X-ray and Fourier transform infrared analysis. The in- crease in optical transparency of doped ADP crystal was ascertained in the range of 200-900 nm using the UV-visible spectral analysis. The vital optical constants were evaluated using the transmittance data to explore various optical device applications of crystal. The assertive influence of SMS on mechanical and dielectric behavior of ADP crystal was investigated by means of Vickers microhardness analysis and dielectric studies, respectively. The enhancement in second harmonic generation （SHG） efficiency of SMS doped ADP crystal with reference to potassium dihydrogen phosphate （KDP） and ADP was confirmed from Kurtz-Perry SHG test. The Kerr lensing nonlinearity in SMS doped ADP crystal was identified by means of Z-scan analysis and the third order nonlinear optical susceptibility （χ3） was found to be 6.19 × 10-5 esu, which vitalizes its application for laser stabilization systems.
基金editorial office of Geodesy and Geodynamics,for constant support。
文摘Crustal deformation and neotectonics are well-understood phenomena that happen almost on every part of the Earth and have some diastrophic effects on the Earth’s surface.To understand these effects,Remote Sensing(RS)and(GIS)have sharpened the human ability to learn about the scientiflc reasons for the Earth’s dynamic activities,including active tectonics and surface landform changes in spatially and temporally.
