The Laizhou Bay(LB)represents a substantial ecological area that is vulnerable to human activities and confronts diverse environmental challenges.This study provides a comprehensive characterization of nutrients,petro...The Laizhou Bay(LB)represents a substantial ecological area that is vulnerable to human activities and confronts diverse environmental challenges.This study provides a comprehensive characterization of nutrients,petroleum,heavy metals,and phytoplankton community structure across seven distinct areas in LB.The results indicate relatively high concentrations of NO_(2)-N,SiO_(4)-Si,and NO_(3)-N in the Southwest Laizhou Bay(SWLB)and Huanghe River Estuary(HRE).In contrast,the East Laizhou bay(ELB)and the North of Huanghe River Estuary(NHRE)exhibit the highest concentrations of heavy metals(As,Cr and Hg).The areas with high phytoplankton density and community diversity are mainly located in the SWLB.After adjusting for basic environmental factors,phytoplankton density and Margalef richness index D are significantly associated with nutrients(NO_(3)-N,NO_(2)-N,NH_(4)-N,SiO_(4)-Si),and heavy metal(Cr)concentrations.We highlight that,in addition to Xiaoqinghe River,nutrients brought by the Mihe River in the SWLB and heavy metal(Cr)pollution in the ELB resulting from industrial and mining activities along the coast significantly influence phytoplankton growth and community structure.Therefore,it is recommended that more monitoring and management efforts be focused on these regions in the future.展开更多
By anayses of carbon isotopic composition (δ13C values) of the benthos collected in the Laoshan Bay in August 1993 and February and May 1994, it is found that the main food sources of the benthos can be divided into ...By anayses of carbon isotopic composition (δ13C values) of the benthos collected in the Laoshan Bay in August 1993 and February and May 1994, it is found that the main food sources of the benthos can be divided into four groups in terms of carbon isotope composition: Particulate Organic Matter (POM), benthic diatoms, benthic macroalgae and the organic matter in sediments. The results show that the carbon isotopic composition of the benthic animals has a close relation with that of the food they take in. The Carbon isotopic compositions of benthos may be useful in elucidating their food sources. The carbon isotopic data have confirmed that POM is the main food source of the benthic filter feeders such as bivalves; crustaceans have a wide range of δ13C values, showing their food source has diversity; benthic diatoms are an important fraction of the food for most of gastropods. A preliminary investigation of the benthic-pelagic coupling in that region using the stable carban isotopic tracers has confirmed the importance of POM as a food source for benthos in this region, but the organic matter in sediments and benthic diatoms are also relatively important for a lot of benthic animals. The benthic-pelagic coupling in the Laoshan Bay temperate ecosystem is not so tight as that in ecosystems at higher latitudes such as northeastern water polynya.展开更多
A total of 2 088 marine microorganisms including 1 392 strains of bacteria and 696 strains of fungi were isolated from diverse marine environment such as the South Pole, the North Pole, and Qingdao tideland, etc. Thro...A total of 2 088 marine microorganisms including 1 392 strains of bacteria and 696 strains of fungi were isolated from diverse marine environment such as the South Pole, the North Pole, and Qingdao tideland, etc. Through a systematic screening process involving the use of Pyricularia oryzae mode, 90 bacteria and 31 fungi strains demonstrating positive bioactivities were identified. The rates of active strains of marine bacteria and marine fungi were 6.5% and 4.5%, respectively. The relationships between the active strains and the sampling locations and hosts were studied. For marine bacteria, the three locations showing the highest rotes of active strains were 8.4% in the Zhujiang Estuary, 7.2% at the North Pole and 6.3% in the Bohai Sea. For marine fungi, the highest rates observed were 7.8% at the South Pole, 7.4% in the South China Sea and 6.8% at the Qingdao tideland. An analysis of the host showed that the three highest rates of active strain for marine bacteria were 8.2% for seawater from the Zhujiang Estuary, 8% for alga from the Qingdao tideland and 7.6% for sea mud from the North Pole. For marine fungi, the highest rates observed were 8.3% for Qingdao actiniae, 7.4% for South China Sea poriferan and 4.5% for soil of Qingdao Suaeda salsa. Four fungi and two bacteria samples were selected for further study because of their high bioactivity. They were found to be active towards several pathogenic microorganisms, and demonstrated stable genetic and thermal characteristics and conservation activities.展开更多
基金the National Natural Science Foundation of China(Nos.42176234 and 42130403)the Chinese Arctic and Antarctic Creative Program(No.JDXT2018-01)the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(No.GML2019ZD0402).
文摘The Laizhou Bay(LB)represents a substantial ecological area that is vulnerable to human activities and confronts diverse environmental challenges.This study provides a comprehensive characterization of nutrients,petroleum,heavy metals,and phytoplankton community structure across seven distinct areas in LB.The results indicate relatively high concentrations of NO_(2)-N,SiO_(4)-Si,and NO_(3)-N in the Southwest Laizhou Bay(SWLB)and Huanghe River Estuary(HRE).In contrast,the East Laizhou bay(ELB)and the North of Huanghe River Estuary(NHRE)exhibit the highest concentrations of heavy metals(As,Cr and Hg).The areas with high phytoplankton density and community diversity are mainly located in the SWLB.After adjusting for basic environmental factors,phytoplankton density and Margalef richness index D are significantly associated with nutrients(NO_(3)-N,NO_(2)-N,NH_(4)-N,SiO_(4)-Si),and heavy metal(Cr)concentrations.We highlight that,in addition to Xiaoqinghe River,nutrients brought by the Mihe River in the SWLB and heavy metal(Cr)pollution in the ELB resulting from industrial and mining activities along the coast significantly influence phytoplankton growth and community structure.Therefore,it is recommended that more monitoring and management efforts be focused on these regions in the future.
基金National Natual Science Foundation of China under contract No.39170172.
文摘By anayses of carbon isotopic composition (δ13C values) of the benthos collected in the Laoshan Bay in August 1993 and February and May 1994, it is found that the main food sources of the benthos can be divided into four groups in terms of carbon isotope composition: Particulate Organic Matter (POM), benthic diatoms, benthic macroalgae and the organic matter in sediments. The results show that the carbon isotopic composition of the benthic animals has a close relation with that of the food they take in. The Carbon isotopic compositions of benthos may be useful in elucidating their food sources. The carbon isotopic data have confirmed that POM is the main food source of the benthic filter feeders such as bivalves; crustaceans have a wide range of δ13C values, showing their food source has diversity; benthic diatoms are an important fraction of the food for most of gastropods. A preliminary investigation of the benthic-pelagic coupling in that region using the stable carban isotopic tracers has confirmed the importance of POM as a food source for benthos in this region, but the organic matter in sediments and benthic diatoms are also relatively important for a lot of benthic animals. The benthic-pelagic coupling in the Laoshan Bay temperate ecosystem is not so tight as that in ecosystems at higher latitudes such as northeastern water polynya.
文摘A total of 2 088 marine microorganisms including 1 392 strains of bacteria and 696 strains of fungi were isolated from diverse marine environment such as the South Pole, the North Pole, and Qingdao tideland, etc. Through a systematic screening process involving the use of Pyricularia oryzae mode, 90 bacteria and 31 fungi strains demonstrating positive bioactivities were identified. The rates of active strains of marine bacteria and marine fungi were 6.5% and 4.5%, respectively. The relationships between the active strains and the sampling locations and hosts were studied. For marine bacteria, the three locations showing the highest rotes of active strains were 8.4% in the Zhujiang Estuary, 7.2% at the North Pole and 6.3% in the Bohai Sea. For marine fungi, the highest rates observed were 7.8% at the South Pole, 7.4% in the South China Sea and 6.8% at the Qingdao tideland. An analysis of the host showed that the three highest rates of active strain for marine bacteria were 8.2% for seawater from the Zhujiang Estuary, 8% for alga from the Qingdao tideland and 7.6% for sea mud from the North Pole. For marine fungi, the highest rates observed were 8.3% for Qingdao actiniae, 7.4% for South China Sea poriferan and 4.5% for soil of Qingdao Suaeda salsa. Four fungi and two bacteria samples were selected for further study because of their high bioactivity. They were found to be active towards several pathogenic microorganisms, and demonstrated stable genetic and thermal characteristics and conservation activities.
