Seasonal variations and causes for these were elaborated for fishery resources in Shenzhen sea area,to provide scientific basis for sustainable utilization and management of fishery resources in typical fisheries of S...Seasonal variations and causes for these were elaborated for fishery resources in Shenzhen sea area,to provide scientific basis for sustainable utilization and management of fishery resources in typical fisheries of South China Sea coasts. Based on the data of fishery resources collected through trawl surveys in Egong Bay fisheries area,Shenzhen,from August( autumn) and December( winter) of 2012 to March(spring) and May(summer) of 2013,seasonal variation of nekton species composition,stock density,dominant species composition,size spectra and biodiversity were studied. Results showed that there were 113 species of nekton in Shenzhen sea area,which belonged to 78 genus,50 families,14 orders and 3 classes. The number of species was the largest in summer(61 species) and smallest in autumn(53 species). In spring and winter,there was 56 species. The stock density and individual density of nekton were the minimum in summer(5950. 20 kg/km2 and 356. 45 ind/km2,respectively),whereas the percentage of fish stock density and individual density were the highest in summer(51. 99%and 42. 19%). The seasonal variations of size spectra indicated that fishing intensity was the highest in autumn,and was the lowest in summer. Additionally,biodiversity index presented significant seasonal variations,including Shannon-Wiener diversity index( H '),Margalef richness index( D') and Pielou evenness index( J'),with the same trend as summer > spring > autumn > winter. In conclusion,there are clear seasonal variations in the nekton species,biomass and structure in Egong Bay fisheries area in Shenzhen. Due to the difference in fishing intensity in different seasons( low intensity in summer and high intensity in autumn),community structure and function in summer are more stable than that in autumn and winter. Particularly,with the increase in the fishing intensity in autumn,k selection species will be replaced by r selection species.展开更多
[Objective] The ecosystem health of the Egong Bay fisheries area in Shenzhen was assessed,based on the index of biological integrity of fish( F-IBI),for the reference of ecological restoration in typical fisheries are...[Objective] The ecosystem health of the Egong Bay fisheries area in Shenzhen was assessed,based on the index of biological integrity of fish( F-IBI),for the reference of ecological restoration in typical fisheries area in the coast of South China Sea. [Method]Based on four seasons survey from August( summer) and November( autumn) in 2012 to February( winter) and May( spring) in 2013,six indicators including total species number of fish,percentage of Sciaenidae species,percentage of Sparidae species,percentage of planktivorous species,percentage of benthic-feeding species and percentage of benthic-feeding and piscivorous species,were used in computing F-IBI of Egong Bay. The suitability of F-IBI was tested by principal component analysis( PCA) and Pearson correlation analysis. [Result]Total species number of fish,percentage of Sciaenidae species,percentage of Sparidae species,percentage of planktivorous species and percentage of benthic-feeding species were major assessment indicators for Egong Bay fisheries area. F-IBI of Egong Bay fisheries area was correlated with water temperature,salinity,chemical oxygen demand( COD) and petroleum,and was negative correlation to p H,dissolved oxygen( DO),dissolved inorganic nitrogen( DIN),reactive phosphate( PO_4^(3-)-P),and suspended matters. There were significant correction between the F-IBI with the salinity,COD,and suspended matters.[Conclusion]F-IBI system,based on total species number of fish,percentage of Sciaenidae species,percentage of Sparidae species,percentage of planktivorous species,percentage of benthic-feeding species and percentage of benthic-feeding and piscivorous species was feasible in Egong Bay fisheries area.展开更多
Leveraging the commercial CFD software FLUENT,the fine-scale three-dimensional wind structure over the Paiya Mountains on the Dapeng Peninsula near Shenzhen,a city on the seashore of South China Sea,during the landfal...Leveraging the commercial CFD software FLUENT,the fine-scale three-dimensional wind structure over the Paiya Mountains on the Dapeng Peninsula near Shenzhen,a city on the seashore of South China Sea,during the landfall of Typhoon Molave has been simulated and analyzed.Through the study,a conceptual wind structure model for mountainous areas under strong wind condition is established and the following conclusions are obtained as follows:(1)FLUENT can reasonably simulate a three-dimensional wind structure over mountainous areas under strong wind conditions;(2)the kinetic effect of a mountain can intensify wind speed in the windward side of the mountain and the area over the mountain peak;and(3)in the leeward side of the mountain,wind speed is relatively lower with relatively stronger wind shear and turbulence.展开更多
基金Supported by National Key Technology Research and Development Program of the Ministry of Science and Technology of China(2012BAD18B01&2012BAD18B02)Science and Technology Planning Project of Shenzhen(JSGG20141015154342147&JCYJ20160331141759795)
文摘Seasonal variations and causes for these were elaborated for fishery resources in Shenzhen sea area,to provide scientific basis for sustainable utilization and management of fishery resources in typical fisheries of South China Sea coasts. Based on the data of fishery resources collected through trawl surveys in Egong Bay fisheries area,Shenzhen,from August( autumn) and December( winter) of 2012 to March(spring) and May(summer) of 2013,seasonal variation of nekton species composition,stock density,dominant species composition,size spectra and biodiversity were studied. Results showed that there were 113 species of nekton in Shenzhen sea area,which belonged to 78 genus,50 families,14 orders and 3 classes. The number of species was the largest in summer(61 species) and smallest in autumn(53 species). In spring and winter,there was 56 species. The stock density and individual density of nekton were the minimum in summer(5950. 20 kg/km2 and 356. 45 ind/km2,respectively),whereas the percentage of fish stock density and individual density were the highest in summer(51. 99%and 42. 19%). The seasonal variations of size spectra indicated that fishing intensity was the highest in autumn,and was the lowest in summer. Additionally,biodiversity index presented significant seasonal variations,including Shannon-Wiener diversity index( H '),Margalef richness index( D') and Pielou evenness index( J'),with the same trend as summer > spring > autumn > winter. In conclusion,there are clear seasonal variations in the nekton species,biomass and structure in Egong Bay fisheries area in Shenzhen. Due to the difference in fishing intensity in different seasons( low intensity in summer and high intensity in autumn),community structure and function in summer are more stable than that in autumn and winter. Particularly,with the increase in the fishing intensity in autumn,k selection species will be replaced by r selection species.
基金Supported by National Science and Technology Support Program(2012BAD18B01)Shenzhen Science and Technology Plan Project(JSGG20141015154342147,JCYJ20160331141759795)
文摘[Objective] The ecosystem health of the Egong Bay fisheries area in Shenzhen was assessed,based on the index of biological integrity of fish( F-IBI),for the reference of ecological restoration in typical fisheries area in the coast of South China Sea. [Method]Based on four seasons survey from August( summer) and November( autumn) in 2012 to February( winter) and May( spring) in 2013,six indicators including total species number of fish,percentage of Sciaenidae species,percentage of Sparidae species,percentage of planktivorous species,percentage of benthic-feeding species and percentage of benthic-feeding and piscivorous species,were used in computing F-IBI of Egong Bay. The suitability of F-IBI was tested by principal component analysis( PCA) and Pearson correlation analysis. [Result]Total species number of fish,percentage of Sciaenidae species,percentage of Sparidae species,percentage of planktivorous species and percentage of benthic-feeding species were major assessment indicators for Egong Bay fisheries area. F-IBI of Egong Bay fisheries area was correlated with water temperature,salinity,chemical oxygen demand( COD) and petroleum,and was negative correlation to p H,dissolved oxygen( DO),dissolved inorganic nitrogen( DIN),reactive phosphate( PO_4^(3-)-P),and suspended matters. There were significant correction between the F-IBI with the salinity,COD,and suspended matters.[Conclusion]F-IBI system,based on total species number of fish,percentage of Sciaenidae species,percentage of Sparidae species,percentage of planktivorous species,percentage of benthic-feeding species and percentage of benthic-feeding and piscivorous species was feasible in Egong Bay fisheries area.
基金National Natural Science Foundation of China(91215302,51278308)Open Project for State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry,Institute of Atmospheric Physics(LAPC)
文摘Leveraging the commercial CFD software FLUENT,the fine-scale three-dimensional wind structure over the Paiya Mountains on the Dapeng Peninsula near Shenzhen,a city on the seashore of South China Sea,during the landfall of Typhoon Molave has been simulated and analyzed.Through the study,a conceptual wind structure model for mountainous areas under strong wind condition is established and the following conclusions are obtained as follows:(1)FLUENT can reasonably simulate a three-dimensional wind structure over mountainous areas under strong wind conditions;(2)the kinetic effect of a mountain can intensify wind speed in the windward side of the mountain and the area over the mountain peak;and(3)in the leeward side of the mountain,wind speed is relatively lower with relatively stronger wind shear and turbulence.