The process of habitat degradation varies in habitat type and driving force which shows certain spatial and temporal heterogeneity on regional scales. In the present study, a new diagnostic model for enclosed bay habi...The process of habitat degradation varies in habitat type and driving force which shows certain spatial and temporal heterogeneity on regional scales. In the present study, a new diagnostic model for enclosed bay habitat degradation was established, with which the spatial and temporal variation patterns of habitat degradation during 1991–2012 in Sansha Bay, Fujian, China was investigated. The results show that anthropogenic disturbance is the major controlling factor for the habitat degradation in large temporal heterogeneity in the bay. On the other hand, the habitat degradation experienced signifi cant spatial variations among six sub-bays. Under the joint action of temporal and spatial heterogeneity, the degradation trend in growing scale shows a more signifi cant correlation with the distribution of local leading industries along shorelines. Therefore, we quantifi ed the main characters of habitat degradation in Sansha Bay, and have understood the relationship between the status of habitats spatio-temporal variation value and the main controlling factor leading to the changes. However, a defi ciency of this research is the lack of or inaccessible to the detailed data, which shall be better solved in the future study for accessing more data from more sources.展开更多
Unbalanced inputs and outputs of material are the root cause of habitat degradation in Sansha Bay,Fujian Province,China. However,the cumulative pollution varies in different geographic locations and natural conditions...Unbalanced inputs and outputs of material are the root cause of habitat degradation in Sansha Bay,Fujian Province,China. However,the cumulative pollution varies in different geographic locations and natural conditions in the enclosed bay. In this study,hydrodynamic conditions,sediment characteristics,and aquaculture methods were recognized as the underlying causes of spatial heterogeneity in the distribution of nitrogen and phosphorous pollutants,the two major controlling factors of habitat degradation in the bay area. In order to achieve the goal of balancing nutrient inputs and outputs in Sansha Bay,we developed a feasible and practical zone restoration strategy for reasonable adjustment and arrangement of aquaculture species and production scale in accordance with varying hydrodynamic conditions and sediment characteristics in six sub-bay areas(sub-systems). The proposed zone restoration strategy lays a solid foundation for habitat restoration and management in Sansha Bay.展开更多
This study analyzes water-level variability in Sansha Bay and its adjacent waters near Fujian, China, using water-level data observed from seven stations along the coast and wind data observed from a moored buoy near ...This study analyzes water-level variability in Sansha Bay and its adjacent waters near Fujian, China, using water-level data observed from seven stations along the coast and wind data observed from a moored buoy near Mazu Island. At super-to near-inertial frequencies, tides dominated the water-level variations, mainly characterized by semi-diurnal (prmafily M2, S2, and N2) and diurnal tides (primarily Kb O1). The correlation coefficients between residual (non-tidal) water-level time series and the observed wind-stress time series exceeded 0.78 at all stations, hinting that the wind acting on the study region was another factor modulating the water-level variability. A cross-wavelet and wavelet-coherence analysis further indicated that (i) the residual water level at each station was more coherent and out-of-phase with the alongshore winds mostly at sub-inertial time scales associated with synoptic weather changes; and (ii) the residual water-level difference between the outer and inner bay was more coherent with the cross-shore winds at discrete narrow frequency bands, with the wind leading by a certain phase. The analysis also implied that the monsoon relaxation period was more favorable for the formation of the land-sea breeze, modulating the residual water-level difference.展开更多
Low biological productivity causes ecosystem energy deficiency.Sansha Bay is an important spawning and nursery ground for migratory fish in the East China Sea(ECS).There is significant mariculture in this area,but sto...Low biological productivity causes ecosystem energy deficiency.Sansha Bay is an important spawning and nursery ground for migratory fish in the East China Sea(ECS).There is significant mariculture in this area,but stock enhancement programs and seasonal fishery closures have failed to recover populations of the commercially important species,Larimichthys crocea.We want to figure out the potential reason of unsuccessful L.crocea resource in recent 30 years.In this study,the trophic status of L.crocea,the food source proportions of L.crocea and zooplankton,and the food web structure and functioning of Sansha Bay was analyzed.A high nutrient low chlorophyll phenomenon was observed:this prevented harmful algal blooms,and phytoplankton growth was restrained by intensive macroalgal culture,resulting in a low abundance of zooplankton in Sansha Bay.Phytoplankton was the most important food source of zooplankton,and zooplankton was the greatest food source of juvenile L.crocea.Analyzed L.crocea suffered from starvation.Crucially,most of the phytoplankton was not used efficiently in the Sansha Bay ecosystem.This study suggests that trophic bottleneck,caused by food limitation,is a potential reason for unsuccessful fishery recovery in enclosed bay with macroalgal culture.展开更多
With the advantages of wide distribution,fast growth,and broad metabolic spectrum to organic carbon compounds,Vibrio may play an important role in organic carbon cycling.However,the ecological roles of Vibrio in many ...With the advantages of wide distribution,fast growth,and broad metabolic spectrum to organic carbon compounds,Vibrio may play an important role in organic carbon cycling.However,the ecological roles of Vibrio in many marine environments have not been explored.Here,the world's deepest'blue hole',the Sansha Yongle Blue Hole(SYBH)in the South China Sea,which is a geographically semi-enclosed environment featuring unique chemical characters,was investigated.The abundance,diversity and carbon source utilization capability of Vibrio were studied by quantification and high-throughput sequencing of Vibrio specific 16S rRNA genes and cultivation methods.The abundance of Vibrio in water column of the SYBH ranged from 3.78×10^4 to 7.35×10^616S rRNA gene copies L_1.Free-living Vibrio was more abundant than particle-associated Vibrio(~1.20×10^6 versus-2.68×10^5 gene copies L_1),indicating that Vibrio prefers a free-living life style.The Vibrio assemblages showed clear vertical stratification and could be divided into three groups:aerobic-transition,middle anaerobic and bottom anaerobic zones.Dissolved oxygen(DO),temperature,pH and salinity were the main environmental factors affecting the abundance and community composition.Cultivated Vibrio demonstrated a degrading capability to various macromolecular substrates,including starch,Tween 20/40/80,DNA,gelatin,alginate,casein,chitin,lecithin,K-carrageenan,mannan,xylan and hyaluronic acid.This suggests that Vibrio could produce a variety of highly active extracellular enzymes.Our study provides new insights into the distribution pattern and possible role in carbon cycle of Vibrio in the unique environment of a"blue hole'.展开更多
基金Supported by the Public Science and Technology Research Funds Projects of Ocean(No.201205009)
文摘The process of habitat degradation varies in habitat type and driving force which shows certain spatial and temporal heterogeneity on regional scales. In the present study, a new diagnostic model for enclosed bay habitat degradation was established, with which the spatial and temporal variation patterns of habitat degradation during 1991–2012 in Sansha Bay, Fujian, China was investigated. The results show that anthropogenic disturbance is the major controlling factor for the habitat degradation in large temporal heterogeneity in the bay. On the other hand, the habitat degradation experienced signifi cant spatial variations among six sub-bays. Under the joint action of temporal and spatial heterogeneity, the degradation trend in growing scale shows a more signifi cant correlation with the distribution of local leading industries along shorelines. Therefore, we quantifi ed the main characters of habitat degradation in Sansha Bay, and have understood the relationship between the status of habitats spatio-temporal variation value and the main controlling factor leading to the changes. However, a defi ciency of this research is the lack of or inaccessible to the detailed data, which shall be better solved in the future study for accessing more data from more sources.
基金Supported by the Projects of Public Science and Technology Research Funds of Ocean Sector of China(No.201205009)the National Natural Science Foundation of China(No.41201569)
文摘Unbalanced inputs and outputs of material are the root cause of habitat degradation in Sansha Bay,Fujian Province,China. However,the cumulative pollution varies in different geographic locations and natural conditions in the enclosed bay. In this study,hydrodynamic conditions,sediment characteristics,and aquaculture methods were recognized as the underlying causes of spatial heterogeneity in the distribution of nitrogen and phosphorous pollutants,the two major controlling factors of habitat degradation in the bay area. In order to achieve the goal of balancing nutrient inputs and outputs in Sansha Bay,we developed a feasible and practical zone restoration strategy for reasonable adjustment and arrangement of aquaculture species and production scale in accordance with varying hydrodynamic conditions and sediment characteristics in six sub-bay areas(sub-systems). The proposed zone restoration strategy lays a solid foundation for habitat restoration and management in Sansha Bay.
文摘This study analyzes water-level variability in Sansha Bay and its adjacent waters near Fujian, China, using water-level data observed from seven stations along the coast and wind data observed from a moored buoy near Mazu Island. At super-to near-inertial frequencies, tides dominated the water-level variations, mainly characterized by semi-diurnal (prmafily M2, S2, and N2) and diurnal tides (primarily Kb O1). The correlation coefficients between residual (non-tidal) water-level time series and the observed wind-stress time series exceeded 0.78 at all stations, hinting that the wind acting on the study region was another factor modulating the water-level variability. A cross-wavelet and wavelet-coherence analysis further indicated that (i) the residual water level at each station was more coherent and out-of-phase with the alongshore winds mostly at sub-inertial time scales associated with synoptic weather changes; and (ii) the residual water-level difference between the outer and inner bay was more coherent with the cross-shore winds at discrete narrow frequency bands, with the wind leading by a certain phase. The analysis also implied that the monsoon relaxation period was more favorable for the formation of the land-sea breeze, modulating the residual water-level difference.
基金This work was supported by the Ministry of Science and Technology of the People’s Republic of China under Grant number[2018YFC1406306].
文摘Low biological productivity causes ecosystem energy deficiency.Sansha Bay is an important spawning and nursery ground for migratory fish in the East China Sea(ECS).There is significant mariculture in this area,but stock enhancement programs and seasonal fishery closures have failed to recover populations of the commercially important species,Larimichthys crocea.We want to figure out the potential reason of unsuccessful L.crocea resource in recent 30 years.In this study,the trophic status of L.crocea,the food source proportions of L.crocea and zooplankton,and the food web structure and functioning of Sansha Bay was analyzed.A high nutrient low chlorophyll phenomenon was observed:this prevented harmful algal blooms,and phytoplankton growth was restrained by intensive macroalgal culture,resulting in a low abundance of zooplankton in Sansha Bay.Phytoplankton was the most important food source of zooplankton,and zooplankton was the greatest food source of juvenile L.crocea.Analyzed L.crocea suffered from starvation.Crucially,most of the phytoplankton was not used efficiently in the Sansha Bay ecosystem.This study suggests that trophic bottleneck,caused by food limitation,is a potential reason for unsuccessful fishery recovery in enclosed bay with macroalgal culture.
基金This work was supported by the National Natural Science Foundation of China(Grants nos.41730530,91751202 and 41476112).
文摘With the advantages of wide distribution,fast growth,and broad metabolic spectrum to organic carbon compounds,Vibrio may play an important role in organic carbon cycling.However,the ecological roles of Vibrio in many marine environments have not been explored.Here,the world's deepest'blue hole',the Sansha Yongle Blue Hole(SYBH)in the South China Sea,which is a geographically semi-enclosed environment featuring unique chemical characters,was investigated.The abundance,diversity and carbon source utilization capability of Vibrio were studied by quantification and high-throughput sequencing of Vibrio specific 16S rRNA genes and cultivation methods.The abundance of Vibrio in water column of the SYBH ranged from 3.78×10^4 to 7.35×10^616S rRNA gene copies L_1.Free-living Vibrio was more abundant than particle-associated Vibrio(~1.20×10^6 versus-2.68×10^5 gene copies L_1),indicating that Vibrio prefers a free-living life style.The Vibrio assemblages showed clear vertical stratification and could be divided into three groups:aerobic-transition,middle anaerobic and bottom anaerobic zones.Dissolved oxygen(DO),temperature,pH and salinity were the main environmental factors affecting the abundance and community composition.Cultivated Vibrio demonstrated a degrading capability to various macromolecular substrates,including starch,Tween 20/40/80,DNA,gelatin,alginate,casein,chitin,lecithin,K-carrageenan,mannan,xylan and hyaluronic acid.This suggests that Vibrio could produce a variety of highly active extracellular enzymes.Our study provides new insights into the distribution pattern and possible role in carbon cycle of Vibrio in the unique environment of a"blue hole'.
基金funded by Tianjin Science and Technology Planning Project(20KPHDRC00070)basic scientific research fees of Chinese Academy of Agricultural Sciences(Y2022LM15)+1 种基金the Key Research and Development Program of Hainan Province(ZDYF2022XDNY214ZDYF2017056)。
文摘为全面调查中国海南省三沙市永兴岛的跳小蜂科物种多样性,于2017~2020年期间采集了永兴岛的跳小蜂。经鉴定,共发现跳小蜂10种,包含1新种:Ooencyrtus yongxingensis Zu&Xue sp.nov.及2中国新记录种:Adelencyrtus mangiphila(Risbec,1952),Metaphycus agarwali Hayat and Subba Rao,1981。文中还提供了永兴岛跳小蜂科名录。