Research On Metazoan Benthic Biomass Size Spectrum In Two Significant Different Sediment Environments Of The Southern Yellow Sea, China

In spite of detailed variety across temporal and spatial scale, conservative bimodal metazoan benthic biomass size spectra have been observed in different environmental condition. Sheldon-type and normalized biomass size spectra of metazoan benthos are constructed in two significant different sediment environments: sandy intertidal zone and subtidal zone composed by carbonate ooze in the Southern Yellow sea. Seasonal variation of biomass size spectrum is analyzed by data of the sandy intertidal zone. Secondary productions and oxygen consumptions of metazoan benthic assemblages are estimated by the method of continuous integral model.Significant seasonal variations of abiotic and biotic factors are revealed in sandy intertidal zone. Environmental factors can be separated to two seasons: temperate summer with poor dissolved oxygen (DO) and chilly winter with rich DO. In sharp alternation between the two seasons, high variability of environment is observed. Average abundance of meiofauna is 1025.40±168.84ind/10cm~2, average biomass is 1195.87μg dwt/10 cm~2; average abundance of macrofauna is 1574 ind./m~2, average biomass is 4.531g/m~2. Meiofauna abundance has two peaks in whole year, appearing in May and December. DO directs the change of benthos in summer and chilliness in winter.Structure of biomass size spectrum is transformed seasonally. Sheldon-type biomass size spectra appear tri-modal at January and April, but bimodal with a strong trough at July and October. Closely coupling between trough's strength and DO suggests that species locating in the size classes of trough might be more sensitive to hypoxia than other size classes.All normalization biomass size spectra fit linear regression reasonably. But two different troughs are revealed by analyzing standardized residuals of normalized...