Energy flow of the macrozoobenthic community in an algal lake, Houhu Lake (Wuhan, China) was investigated from April, 1996 to March, 1997. The estimated consumption of the community was 2522.7 kJ/(m 2·a); defecat...Energy flow of the macrozoobenthic community in an algal lake, Houhu Lake (Wuhan, China) was investigated from April, 1996 to March, 1997. The estimated consumption of the community was 2522.7 kJ/(m 2·a); defecation was 2049.1 kJ/(m 2·a); metabolism 371.2 kJ/(m 2·a); excretion 34.7 kJ/(m 2·a) and production 67.7 kJ/(m 2·a). The assimilation rate of the community was 19%; and 81% of its ingestion was defecated. The computed net growth efficiency was 14%, much lower than most reported values, which meant that the macrozoobenthic community in Houhu Lake utilized food less effectively.展开更多
We propose a bio-optical inversion model that retrieves the absorption contributions of phytoplankton and colored detrital matter(CDM),as well as the phytoplankton size classes(PSCs),from total minus water absorption ...We propose a bio-optical inversion model that retrieves the absorption contributions of phytoplankton and colored detrital matter(CDM),as well as the phytoplankton size classes(PSCs),from total minus water absorption spectra.The model is based on three-component separation of phytoplankton size structure and a genetic algorithm.The model performance was tested on two independent datasets(the NASA bio-Optical Marine Algorithm Dataset(NOMAD) and the northern South China Sea(NSCS) dataset).The relationships between the estimated and measured values were strongly linear,especially for aCDM(412),and the Root Mean Square Error(RMSE) of the CDM exponential slope(SCDM) was relatively low.Next,the inversion model was directly applied to in-situ total minus water absorption spectra determined by an underwater meter during a cruise in September 2008,to retrieve the phytoplankton size structure in the seawater.By comparing the measured and retrieved chlorophyll a concentrations,we demonstrated that total and size-specific chlorophyll a concentrations could be retrieved by the model with relatively high accuracy.Finally,we applied the bio-optical inversion model to investigate changes in phytoplankton size structure induced by an anti-cyclonic eddy in the NSCS.展开更多
文摘Energy flow of the macrozoobenthic community in an algal lake, Houhu Lake (Wuhan, China) was investigated from April, 1996 to March, 1997. The estimated consumption of the community was 2522.7 kJ/(m 2·a); defecation was 2049.1 kJ/(m 2·a); metabolism 371.2 kJ/(m 2·a); excretion 34.7 kJ/(m 2·a) and production 67.7 kJ/(m 2·a). The assimilation rate of the community was 19%; and 81% of its ingestion was defecated. The computed net growth efficiency was 14%, much lower than most reported values, which meant that the macrozoobenthic community in Houhu Lake utilized food less effectively.
基金Supported by the Key Projects of the National Natural Science Foundation of China(Nos.41076014,U0933005,41176035,40906022,41206029)
文摘We propose a bio-optical inversion model that retrieves the absorption contributions of phytoplankton and colored detrital matter(CDM),as well as the phytoplankton size classes(PSCs),from total minus water absorption spectra.The model is based on three-component separation of phytoplankton size structure and a genetic algorithm.The model performance was tested on two independent datasets(the NASA bio-Optical Marine Algorithm Dataset(NOMAD) and the northern South China Sea(NSCS) dataset).The relationships between the estimated and measured values were strongly linear,especially for aCDM(412),and the Root Mean Square Error(RMSE) of the CDM exponential slope(SCDM) was relatively low.Next,the inversion model was directly applied to in-situ total minus water absorption spectra determined by an underwater meter during a cruise in September 2008,to retrieve the phytoplankton size structure in the seawater.By comparing the measured and retrieved chlorophyll a concentrations,we demonstrated that total and size-specific chlorophyll a concentrations could be retrieved by the model with relatively high accuracy.Finally,we applied the bio-optical inversion model to investigate changes in phytoplankton size structure induced by an anti-cyclonic eddy in the NSCS.
