The diel vertical migration （DVM） of zooplankton and the influence of upwelling on zooplankton biomass were examined using water column data of current velocity and mean volume backscattering strength （MVBS） colle...The diel vertical migration （DVM） of zooplankton and the influence of upwelling on zooplankton biomass were examined using water column data of current velocity and mean volume backscattering strength （MVBS） collected by moored acoustic Doppler current profilers （ADCPs） deployed in the southeastern Chukchi Sea during the 5th Chinese National Arctic Research Expedition （CHINARE） in summer 2012, combined with the satellite observational data such as sea surface temperature （SST）, wind, and chlorophyll a （Chl a）. Hourly acoustic data were continuously collected for 49-d in the mooring site. Spectral analysis indicated that there were different migrating patterns of zooplankton, even though precisely classifying the zooplankton taxa was not available. The prevailing 24-h cycle corresponded to the normal DVM with zooplankton swimming upwards at sunrise and returning to deep waters at sunset. There was a clear DVM in the upper 17 m of the water column during the period with distinct day-night cycles, and no active DVM throughout the water column when the sun above the horizon （polar day）, suggesting that light intensity was the trigger for DVM. Also there was a second migrating pattern with 12-h cycle. The upwelling event occurring in the northwest of Alaskan coastal area had important influence on zooplankton biomass at the mooring site. During the upwelling, the SST close to the mooring site dropped significantly from maximal 6.35℃to minimal 1.31℃ within five days. Simultaneously, there was a rapid increase in the MVBS and Chl a level, suggesting the aggregation of zooplankton related to upwelling.展开更多
This article studied the diversity of Amphipoda＇s environmental adaptation using statistic method- ology based on the seasonal investigation data obtained from the East China Sea waters （23°30′- 33°N, 118...This article studied the diversity of Amphipoda＇s environmental adaptation using statistic method- ology based on the seasonal investigation data obtained from the East China Sea waters （23°30′- 33°N, 118°30′128°E） from 1997 to 2000. Fifty-four Amphipoda species were identified： among which eight species could stand a temperature difference over 10 ℃ and eight species could tolerate the temperature gap ranged from 5 to 10 ℃; while only six species could stand the salinity fluctuation more than 5. Based on above facts as well as calculated optimal temperature and salinity we divided all Amphipoda species into four groups： （1） eurythermic and euryhalinous species including Lestrigonus schizogeneios, L. macrophthalmus, Tetrathyrus forcipatus, L. bengalensis and Hyperi- oides sibaginis; （2） temperate-warm species containing Hyperoche medusarum, Parathemisto gau- dichaudi, Themisto japonica and Hyperia galba; （3） oceanic tropical species consisted of Oxycephalus clausi~ Lyeaea pulex, Eupronoe minuta, Simorhychotus antennarius, O. poreelus, Platyscelus ovoides and Rhabdosoma ahitei; （4） subtropical species involving one nearshore subtropical water species （Corophium uenoi） and 37 offshore subtropical ones. Compared with other zooplankton such as Eu- phausia and Chaetognatha, Amphipoda was characterized by low dominance but wide distribution in the East China Sea, and this could be ascribed to its high adaptation diversity.展开更多
基金The Public Science and Technology Research Funds Projects of Ocean under contract Nos 201205007-1 and 201405031Chinese Polar Environment Comprehensive Investigation and Assessment Programmes under contract Nos CHINARE-2014-03-01 and CHINARE2014-04-03the Polar Science Strategic Research Foundation of China under contract No.JD201101
文摘The diel vertical migration （DVM） of zooplankton and the influence of upwelling on zooplankton biomass were examined using water column data of current velocity and mean volume backscattering strength （MVBS） collected by moored acoustic Doppler current profilers （ADCPs） deployed in the southeastern Chukchi Sea during the 5th Chinese National Arctic Research Expedition （CHINARE） in summer 2012, combined with the satellite observational data such as sea surface temperature （SST）, wind, and chlorophyll a （Chl a）. Hourly acoustic data were continuously collected for 49-d in the mooring site. Spectral analysis indicated that there were different migrating patterns of zooplankton, even though precisely classifying the zooplankton taxa was not available. The prevailing 24-h cycle corresponded to the normal DVM with zooplankton swimming upwards at sunrise and returning to deep waters at sunset. There was a clear DVM in the upper 17 m of the water column during the period with distinct day-night cycles, and no active DVM throughout the water column when the sun above the horizon （polar day）, suggesting that light intensity was the trigger for DVM. Also there was a second migrating pattern with 12-h cycle. The upwelling event occurring in the northwest of Alaskan coastal area had important influence on zooplankton biomass at the mooring site. During the upwelling, the SST close to the mooring site dropped significantly from maximal 6.35℃to minimal 1.31℃ within five days. Simultaneously, there was a rapid increase in the MVBS and Chl a level, suggesting the aggregation of zooplankton related to upwelling.
基金The China Major Research Plan of the National Natural Science Foundation of China under contract No.90511005"908" Project under contract No.908-02-01-03
文摘This article studied the diversity of Amphipoda＇s environmental adaptation using statistic method- ology based on the seasonal investigation data obtained from the East China Sea waters （23°30′- 33°N, 118°30′128°E） from 1997 to 2000. Fifty-four Amphipoda species were identified： among which eight species could stand a temperature difference over 10 ℃ and eight species could tolerate the temperature gap ranged from 5 to 10 ℃; while only six species could stand the salinity fluctuation more than 5. Based on above facts as well as calculated optimal temperature and salinity we divided all Amphipoda species into four groups： （1） eurythermic and euryhalinous species including Lestrigonus schizogeneios, L. macrophthalmus, Tetrathyrus forcipatus, L. bengalensis and Hyperi- oides sibaginis; （2） temperate-warm species containing Hyperoche medusarum, Parathemisto gau- dichaudi, Themisto japonica and Hyperia galba; （3） oceanic tropical species consisted of Oxycephalus clausi~ Lyeaea pulex, Eupronoe minuta, Simorhychotus antennarius, O. poreelus, Platyscelus ovoides and Rhabdosoma ahitei; （4） subtropical species involving one nearshore subtropical water species （Corophium uenoi） and 37 offshore subtropical ones. Compared with other zooplankton such as Eu- phausia and Chaetognatha, Amphipoda was characterized by low dominance but wide distribution in the East China Sea, and this could be ascribed to its high adaptation diversity.
