Diatoms are a globally successful and eukaryotic photosynthetic organism with an ornamented silica external wall.The relationship between their valve morphology and habitat means that diatoms can be used as bioindicat...Diatoms are a globally successful and eukaryotic photosynthetic organism with an ornamented silica external wall.The relationship between their valve morphology and habitat means that diatoms can be used as bioindicators to characterize the aquatic environment.To estimate the differential distribution and diversity of diatom assemblages along the coastal line,we collected phytoplankton samples from 114 coastal sites of waters of R.O.Korea.We applied the unweighted pair-group technique using the arithmetic averages clustering method to cluster the sampling sites,apart from those where the biota consisted of other groups,such as dinoflagellates,into four regions:the Yellow Sea,South Sea,southern East Sea,and northern East Sea.Indicator species analysis in each region led to the selection of tychoplanktonic,chain-forming,attached species to substrates and psychrophilic indicator diatoms,respectively,each of which represented a planktonic lifestyle associated with one of the four regions.This study shows the diatom assemblages to serve as bioindicators of Korean coastal water in winter,and the subsequent seasonal survey will provide a starting point for the improved understanding of Korean diatom-based ecoregions,in both time and space.展开更多
The Longgan Lake is a shallow mesotrophic macrophyte-dominated lake. According to the high-resolution diatom research from its sediment core, the diatom community succession was built, and the total phosphorus (TP) an...The Longgan Lake is a shallow mesotrophic macrophyte-dominated lake. According to the high-resolution diatom research from its sediment core, the diatom community succession was built, and the total phosphorus (TP) and chlorophyll-a (Chl-a) concentration were quantitatively reconstructed for the past 2000 years, based on the diatom-TP and diatom-Chla transfer functions. The shifts of diatom assemblages also mirrored the developments of aquatic plant, reflecting the characters of aquatic ecosystem evolution. The inferred epilimnetic TP concentration fluctuated within a small range of 36 to 62μg/L, indicating the lake remained a relative stable mesotrophic status in the long historical period. The periodical variations of the diatom assemblage and trophic status suggest a mitigating function of shallow macrophyte-dominated lakes to nutrient input. The changes of lakes’ trophic status don’t linearly respond to the human disturbance in the catchment. The dynamics mechanism of phosphorus in macrophyte-dominated lakes, as inferred from diatoms, will provide a scientific foundation for the prediction of trophic status change in a shallow lake, as well as the lake ecological restoration and management decisions.展开更多
基金The Fund of the Research Project of Korea Institute of Ocean Science&Technology under contract No.PEA0014the National Research Foundation of the Ministry of Science and ICT under contract Nos NRF-2020R1A2C2005970 and NRF-2017M3A9E4072753the Fund of the Korea Institute of Marine Science&Technology Promotion of the Ministry of Ocean and Fisheries under contract No.21210466。
文摘Diatoms are a globally successful and eukaryotic photosynthetic organism with an ornamented silica external wall.The relationship between their valve morphology and habitat means that diatoms can be used as bioindicators to characterize the aquatic environment.To estimate the differential distribution and diversity of diatom assemblages along the coastal line,we collected phytoplankton samples from 114 coastal sites of waters of R.O.Korea.We applied the unweighted pair-group technique using the arithmetic averages clustering method to cluster the sampling sites,apart from those where the biota consisted of other groups,such as dinoflagellates,into four regions:the Yellow Sea,South Sea,southern East Sea,and northern East Sea.Indicator species analysis in each region led to the selection of tychoplanktonic,chain-forming,attached species to substrates and psychrophilic indicator diatoms,respectively,each of which represented a planktonic lifestyle associated with one of the four regions.This study shows the diatom assemblages to serve as bioindicators of Korean coastal water in winter,and the subsequent seasonal survey will provide a starting point for the improved understanding of Korean diatom-based ecoregions,in both time and space.
基金the Scientific Innovation Projects of Chinese Academy of Sciences(KZCX1-SW-12)andthe 973 projects(2002CB412300)
文摘The Longgan Lake is a shallow mesotrophic macrophyte-dominated lake. According to the high-resolution diatom research from its sediment core, the diatom community succession was built, and the total phosphorus (TP) and chlorophyll-a (Chl-a) concentration were quantitatively reconstructed for the past 2000 years, based on the diatom-TP and diatom-Chla transfer functions. The shifts of diatom assemblages also mirrored the developments of aquatic plant, reflecting the characters of aquatic ecosystem evolution. The inferred epilimnetic TP concentration fluctuated within a small range of 36 to 62μg/L, indicating the lake remained a relative stable mesotrophic status in the long historical period. The periodical variations of the diatom assemblage and trophic status suggest a mitigating function of shallow macrophyte-dominated lakes to nutrient input. The changes of lakes’ trophic status don’t linearly respond to the human disturbance in the catchment. The dynamics mechanism of phosphorus in macrophyte-dominated lakes, as inferred from diatoms, will provide a scientific foundation for the prediction of trophic status change in a shallow lake, as well as the lake ecological restoration and management decisions.
