Dominant species of zooplankton community vary with latitude. Though China possesses a vast coastal area in northwestern Pacific, studies on the latitudinal dominant species gradient are rare. We collected zooplankton...Dominant species of zooplankton community vary with latitude. Though China possesses a vast coastal area in northwestern Pacific, studies on the latitudinal dominant species gradient are rare. We collected zooplankton samples from Haizhou Bay(34.56?–35.19?N, 119.51?–120.30?E), Yueqing Bay(28.14?–28.38?N, 121.10?–121.21?E) and Dongshan Bay(23.65?–23.90?N, 117.45?–117.60?E) in May 2012 and May 2013 to preliminarily characterize the latitudinal dominant species distribution. All the samples were collected vertically using a 0.505 mm mesh plankton net with 0.8 m in mouth diameter from bottom to surface. Calanus sinicus, Aidanosagitta crassa, Labidocera euchaeta, Zonosagitta nagae, Acartia pacifica and Paracalanus parvus were found to be dominant. C. sinicus was the most dominant species and the unique one occurred in all three bays. With latitude decreasing, both the abundance and proportion of C. sinicus declined sharply. Cluster analysis showed that the 6 dominant species could be divided into 3 groups, based on their occurrences in the three bays. Our results suggested that the distribution of dominant species along the coast of China has a significant latitudinal gradient. C. sinicus which widely distributes in the coastal water of the northwestern Pacific can well adapt to the temperature at different latitudes. The high abundance in Haizhou Bay indicated that C. sinicus was an exemplary warm-temperate species, and more commonly occurs in the north of China seas. The ecological characteristics of dominant species change from warm-temperate type in high-latitudinal bays to warm water type in low-latitudinal bays.展开更多
Sun-photometer measurements at Hefei,an urban site located in central East China,were examined to investigate the variations of aerosol loading and optical properties.It is found that aerosol optical thickness(AOT)kee...Sun-photometer measurements at Hefei,an urban site located in central East China,were examined to investigate the variations of aerosol loading and optical properties.It is found that aerosol optical thickness(AOT)keeps higher in winter/spring and gets relatively lower in summer/autumn.The large AOT in winter is caused by anthropogenic sulfate/nitrate aerosols,while in spring dust particles elevate the background aerosol loading and the excessive fine-mode particles eventually lead to severe pollution.There is a dramatic decline of AOT during summer,with monthly averaged AOT reaching the maximum in June and soon the minimum in August.Meanwhile,aerosol size decreases consistently and single scattering albedo(SSA)reaches its minimum in July.During summertime large-sized particles play a key role to change the air from clean to mild-pollution situation,while the presence of massive small-sized particles makes the air being even more polluted.These complicated summer patterns are possibly related to the three key processes that are active in the high temperature/humidity environment concentrating on sulfate/nitrate aerosols,i.e.,gas-to-particle transformation,hygroscopic growth,and wet scavenging.Regardless of season,the increase of SSA with increasing AOT occurs across the visible and near-infrared bands,suggesting the dominant negative/cooling effect with the elevated aerosol loading.The SSA spectra under varying AOT monotonically decrease with wavelength.The relatively large slope arises in summer,reinforcing the dominance of sulfate/nitrate aerosols that induce severe pollution in summer season around this city.展开更多
基金funded by the National Natural Science Foundation of China (No. 41176131)the National Special Research Fund for Non-Profit Marine Sector (No. 201305027-8)
文摘Dominant species of zooplankton community vary with latitude. Though China possesses a vast coastal area in northwestern Pacific, studies on the latitudinal dominant species gradient are rare. We collected zooplankton samples from Haizhou Bay(34.56?–35.19?N, 119.51?–120.30?E), Yueqing Bay(28.14?–28.38?N, 121.10?–121.21?E) and Dongshan Bay(23.65?–23.90?N, 117.45?–117.60?E) in May 2012 and May 2013 to preliminarily characterize the latitudinal dominant species distribution. All the samples were collected vertically using a 0.505 mm mesh plankton net with 0.8 m in mouth diameter from bottom to surface. Calanus sinicus, Aidanosagitta crassa, Labidocera euchaeta, Zonosagitta nagae, Acartia pacifica and Paracalanus parvus were found to be dominant. C. sinicus was the most dominant species and the unique one occurred in all three bays. With latitude decreasing, both the abundance and proportion of C. sinicus declined sharply. Cluster analysis showed that the 6 dominant species could be divided into 3 groups, based on their occurrences in the three bays. Our results suggested that the distribution of dominant species along the coast of China has a significant latitudinal gradient. C. sinicus which widely distributes in the coastal water of the northwestern Pacific can well adapt to the temperature at different latitudes. The high abundance in Haizhou Bay indicated that C. sinicus was an exemplary warm-temperate species, and more commonly occurs in the north of China seas. The ecological characteristics of dominant species change from warm-temperate type in high-latitudinal bays to warm water type in low-latitudinal bays.
基金support on PREDE data and the two reviewers for their valuable suggestionssupported by the National Natural Science Foundation of China(Grant Nos.41175032&41575019)
文摘Sun-photometer measurements at Hefei,an urban site located in central East China,were examined to investigate the variations of aerosol loading and optical properties.It is found that aerosol optical thickness(AOT)keeps higher in winter/spring and gets relatively lower in summer/autumn.The large AOT in winter is caused by anthropogenic sulfate/nitrate aerosols,while in spring dust particles elevate the background aerosol loading and the excessive fine-mode particles eventually lead to severe pollution.There is a dramatic decline of AOT during summer,with monthly averaged AOT reaching the maximum in June and soon the minimum in August.Meanwhile,aerosol size decreases consistently and single scattering albedo(SSA)reaches its minimum in July.During summertime large-sized particles play a key role to change the air from clean to mild-pollution situation,while the presence of massive small-sized particles makes the air being even more polluted.These complicated summer patterns are possibly related to the three key processes that are active in the high temperature/humidity environment concentrating on sulfate/nitrate aerosols,i.e.,gas-to-particle transformation,hygroscopic growth,and wet scavenging.Regardless of season,the increase of SSA with increasing AOT occurs across the visible and near-infrared bands,suggesting the dominant negative/cooling effect with the elevated aerosol loading.The SSA spectra under varying AOT monotonically decrease with wavelength.The relatively large slope arises in summer,reinforcing the dominance of sulfate/nitrate aerosols that induce severe pollution in summer season around this city.
