DISTRIBUTION CHARACTERISTICS OF THE FORAMINIFERS IN THE SURFACE SEDIMENTS OF THE PINQING LAKE IN THE EASTERN GUANGDONG PROVINCE AND THEIR ENVIRONMENTAL SIGNIFICANCE
Foraminifera are important protozoa in the marine environment and are sensitive to the environmental changes.Coastal lagoon,as the interconnected zone between the sea and the land,has the obvious habitat gradients.However,there are limited reports on the foraminiferal populations in such a water body currently.This study takes Pinqing Lake,Shanwei City,Guangdong Province,a typical lagoon in China,as a case for the populations'research.From 2021 to 2022,we systematically investigated the water environmental parameters(depth,salinity,pH etc),the sediment characteristics(particle size and contaminant content)and the foraminiferal community composition of 20 sampling sites from the lake.Most of the current water quality of the Pinqing Lake is assigned to Category IV standard or worse,with the phosphate and inorganic nitrogen out of standard seriously;the concentrations of heavy metals,such as Cu,Zn and Hg are relatively high,with concentrations in some areas reaching Category Ⅱ standard.A total of 35 species of 15 genera of the benthic foraminifers were identified in the surface sediments of the lake,with the hyaline components being the main species,followed by the porcellaneous and agglutinated ones.The dominant species are Ammonia aomoriensis,Elphidium advenum,Elphidium hispidulum and Spiroloculina laevigata.The abundance and diversity are higher at the western estuary,comparing to the eastern estuary.Statistical analysis shows that the main environmental factors affecting the distribution of the foraminifers within the lake are the water depth and Cu concentration,which explain 34.2％and 14.9％of the foraminiferal community variance,respectively.This study suggests that the porcellaneous species,such as Triloculina trigonula and Quinqueloculina seminula,be the effective indicators of water depth and salinity;while,Spiroloculina laevigata and Ammonia annectens are the significant indicators of water depth,salinity and heavy metal Cu concentration.
foraminifercommunity characteristicsenvironmental factorsindicatorPinqing Lake
万方数据
维普
