Carbon biomass,carbon-to-chlorophyll a ratio(C꞉Chl a),and the growth rate of phytoplankton cells were studied during four seasonal cruises in 2017 and 2018 in Jiaozhou Bay,China.Water samples were collected from 12 st...Carbon biomass,carbon-to-chlorophyll a ratio(C꞉Chl a),and the growth rate of phytoplankton cells were studied during four seasonal cruises in 2017 and 2018 in Jiaozhou Bay,China.Water samples were collected from 12 stations,and phytoplankton carbon biomass(phyto-C)was estimated from microscope-measured cell volumes.The phyto-C ranged from 5.05 to 78.52μg C/L in the bay,and it constituted a mean of 38.16% of the total particulate organic carbon in the bay.High phyto-C values appeared mostly in the northern or northeastern bay.Diatom carbon was predominant during all four cruises.Dinoflagellate carbon contributed much less(<30%)to the total phyto-C,and high values appeared often in the outer bay.The C꞉Chl a of phytoplankton cells varied from 11.50 to 61.45(mean 31.66),and high values appeared in the outer bay during all four seasons.The phyto-C was also used to calculate the intrinsic growth rates of phytoplankton cells in the bay,and phytoplankton growth rates ranged from 0.56 to 1.96/d;the rate was highest in summer(mean 1.79/d),followed by that in fall(mean 1.24/d)and spring(mean 1.17/d),and the rate was lowest in winter(mean 0.77/d).Temperature and silicate concentration were found to be the determining factors of phytoplankton growth rates in the bay.To our knowledge,this study is the first report on phytoplankton carbon biomass and C꞉Chl a based on water samples in Jiaozhou Bay,and it will provide useful information for studies on carbon-based food web calculations and carbon-based ecosystem models in the bay.展开更多
N_(a)tural populations often persist at the landscape scale as metapopulations,with breeding units(subpopulations)experiencing temporal extinction and recolonization events.Important parameters to forecast population ...N_(a)tural populations often persist at the landscape scale as metapopulations,with breeding units(subpopulations)experiencing temporal extinction and recolonization events.Important parameters to forecast population viability in these systems include the ratio of the effective number of breeders(N_(b))to the total number of adults(N_(a))and migration rates among subpopulations.Here,we present the results of a 10-year integrative monitoring program of a metapopulation of the Iberian green frog(Pelophylax perezi)in central Spain.We characterized population dynamics at two main breeding ponds(Gravera and Laguna)using capture-mark-recapture data to estimate N_(a)in each breeding season,and multilocus genotypes to estimate the effective population size(Ne),N_(b),individual breeding success,and migration rates.Both ponds experienced population decline after a dry season,with Gravera subsequently recovering and Laguna suffering a bottleneck associated with genetic impoverishment.In this subpopulation,average allelic richness and private alleles decreased from 2010(10.87 and 1.67,respectively)to 2018(8.0 and 0.20).The N_(b)/N_(a)ratio in Laguna in 2018 was twice as high(0.95)than in Gravera(0.41)or in pre-bottleneck Laguna(0.50),suggesting plasticity or genetic compensation through increased individual breeding success.Migration rates were asymmetric between ponds,with a stronger contribution from Gravera to Laguna(29.9%vs.16.2%in the opposite direction)that may result in a rescue effect.This study emphasizes the importance of integrative demographic approaches for the monitoring of natural populations based on a better understanding of their spatio-temporal dynamics,which provides valuable information for conservation actions.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.31700425,91751202)the External Cooperation Program of Chinese Academy of Sciences(No.133137KYSB20200002)the Taishan Scholars Project to Song SUN。
文摘Carbon biomass,carbon-to-chlorophyll a ratio(C꞉Chl a),and the growth rate of phytoplankton cells were studied during four seasonal cruises in 2017 and 2018 in Jiaozhou Bay,China.Water samples were collected from 12 stations,and phytoplankton carbon biomass(phyto-C)was estimated from microscope-measured cell volumes.The phyto-C ranged from 5.05 to 78.52μg C/L in the bay,and it constituted a mean of 38.16% of the total particulate organic carbon in the bay.High phyto-C values appeared mostly in the northern or northeastern bay.Diatom carbon was predominant during all four cruises.Dinoflagellate carbon contributed much less(<30%)to the total phyto-C,and high values appeared often in the outer bay.The C꞉Chl a of phytoplankton cells varied from 11.50 to 61.45(mean 31.66),and high values appeared in the outer bay during all four seasons.The phyto-C was also used to calculate the intrinsic growth rates of phytoplankton cells in the bay,and phytoplankton growth rates ranged from 0.56 to 1.96/d;the rate was highest in summer(mean 1.79/d),followed by that in fall(mean 1.24/d)and spring(mean 1.17/d),and the rate was lowest in winter(mean 0.77/d).Temperature and silicate concentration were found to be the determining factors of phytoplankton growth rates in the bay.To our knowledge,this study is the first report on phytoplankton carbon biomass and C꞉Chl a based on water samples in Jiaozhou Bay,and it will provide useful information for studies on carbon-based food web calculations and carbon-based ecosystem models in the bay.
基金the Ethics Committee of Consejo Superior de Investigaciones Científicas,Spain(ref.:710/2018)and Comunidad de Madrid(ref.:PROEX 040/19)which also extended legal permits for tissue collection for scientific purposes(ref.:10/069513.9/18)This study was funded by FEDER/Ministerio de Ciencia,Innovación y Universidades-Agencia Estatal de Investigación,Spain,grant CGL2017-83131-P。
文摘N_(a)tural populations often persist at the landscape scale as metapopulations,with breeding units(subpopulations)experiencing temporal extinction and recolonization events.Important parameters to forecast population viability in these systems include the ratio of the effective number of breeders(N_(b))to the total number of adults(N_(a))and migration rates among subpopulations.Here,we present the results of a 10-year integrative monitoring program of a metapopulation of the Iberian green frog(Pelophylax perezi)in central Spain.We characterized population dynamics at two main breeding ponds(Gravera and Laguna)using capture-mark-recapture data to estimate N_(a)in each breeding season,and multilocus genotypes to estimate the effective population size(Ne),N_(b),individual breeding success,and migration rates.Both ponds experienced population decline after a dry season,with Gravera subsequently recovering and Laguna suffering a bottleneck associated with genetic impoverishment.In this subpopulation,average allelic richness and private alleles decreased from 2010(10.87 and 1.67,respectively)to 2018(8.0 and 0.20).The N_(b)/N_(a)ratio in Laguna in 2018 was twice as high(0.95)than in Gravera(0.41)or in pre-bottleneck Laguna(0.50),suggesting plasticity or genetic compensation through increased individual breeding success.Migration rates were asymmetric between ponds,with a stronger contribution from Gravera to Laguna(29.9%vs.16.2%in the opposite direction)that may result in a rescue effect.This study emphasizes the importance of integrative demographic approaches for the monitoring of natural populations based on a better understanding of their spatio-temporal dynamics,which provides valuable information for conservation actions.
