Study on carbon-phosphorus ratio of eleven reservoirs in Fujian Province
[Background]Carbon(C),nitrogen(N),and phosphorus(P)in water are the main limiting ele-ments that affect the growth of algae and the community structure of phytoplankton.The study of the dissolved inorganic carbon/total phosphorus ratio(DIC/TP)provides an important way to alleviate the eutrophication problem of reservoirs and lakes,which provides a new restoration solution of it.[Objective]The study aims to analyze the nutritional status,phytoplankton community characteristics and carbon-phosphorus ratio of 11 reser-voirs(Mianhuatan Reservoir,Chitan Reservoir,Shanmei Reservoir,Dongzhen Reservoir,Dongzhang Reservoir,Shanzai Reservoir,Dongxi Reservoir,Shidou Reservoir,Guanchang Reservoir,Tangban Reservoir,and Bantou Reservoir)in different areas of Fujian Province in the summer and autumn of 2023.[Methods]In the summer and autumn of 2023,11 reservoirs in different areas of Fujian Province were used as research objects to conduct on-site sampling and monitoring of water quality,phytoplankton and environmental factors.[Results]It was shown that the comprehensive trophic level index(TLI)of 11 reservoirs ranged from 35.9 to 54.4,while Guan-chang Reservior was at the mild eutrophication level,and the other 10 reservoirs were at the mesotrophic level.A total of 5 phytoplankton were detected in the 11 reservoirs.There were 36 genera in the phylum,of which Chlorophyta had the most with 15 genus,Cyanophyta had 11 genus,Bacillariophyta had 7 genus,Pyrrophyta had 2 genus,and Cryptophyta had 1 genus.The density of phytoplankton ranged from 1.13×106 to 5.77×108 cells·L-1,and Cyanophyta was the dominant category in 8 reservoirs(Mianhuatan Reservoir,Chitan Reser-voir,Dongzhen Reservoir,Dongzhang Reservoir,Shanzai Reservoir,Dongxi Reservoir,Guanchang Reservoir,and Tangban Reservoir).The DIC/TP value of water bodies in 11 reservoirs ranged from 17.4 to 402.6,with the lowest DIC/TP value was observed in Guanchang Reservoir in Ningde City,and the highest DIC/TP was ob-served in Chitan Reservoir in Sanming City.Through correlation analysis,it was found that there was a signific-ant negative correlation between DIC/TP,nutritional status index and phytoplankton density.[Conclusion]The carbon-phosphorus ratio has a significant impact on the phytoplankton community structure and eutrophication,and is of great value in exploring simple and low-cost ways to alleviate eutrophication.[Significance]The in-novation of DIC/TP index shows that the difference in limitations of biological utilization of CO2 and P can change the structure and composition of planktonic-submersed plant communities by adjusting the concentra-tion of DIC,TP and DIC/TP in the water body,thereby mitigating eutrophication process in the water bodies.Therefore,based on the carbon and phosphorus limiting effect of aquatic ecosystems,considering the mitiga-tion effect of CO2 on eutrophication and the application of DIC/TP indicators is a win-win situation for protect-ing water quality safety and promoting water body carbon sinks,as well as research on serving and managing ecosystems in the future.
万方数据
维普
