Method for determining point of dredging site of species sources of over-wintering cyanobacterial in large shallow lake

Abstract

Provided is a method for determining points of dredging sites of species sources of over-wintering cyanobacterial in a large shallow lake. The method includes the following steps of: during an over-wintering recovery period, sampling a surface layer of lake sediment, analyzing pigment contents of the surface layer of the lake sediment to characterize total biomass and distribution of the cyanobacterial, and preliminarily screening regions as candidate regions where the total biomass of the species sources of the cyanobacteria are quite higher according to the pigment contents; adding sampling points in the candidate regions and adopting a microscope observation method and a flow cytometric method to determine target populations and the number of the target populations; adopting cell photosynthesis activity and / or esterase activity to characterize physiological activity of cyanobacterial cells; and finely screening the candidate regions according to the number of the target populations and performing correction with the help of the physiological activity of the cyanobacterial cells to preferably select regions where the number of the target populations are larger and the physiological activities are higher from the candidate regions so as to determine the points of the dredging sites of the species sources of the over-wintering cyanobacterial through a grid division method and a spatial interpolation method. By adopting the method in the invention, the points of the dredging sites are determined through distribution characteristics of the species sources of the over-wintering cyanobacterial, which provides scientific and reasonable basis for launching a project for dredging the species sources of the over-wintering cyanobacterial.

Description

technical field [0001] The invention relates to a method for controlling cyanobacteria blooms in large shallow lakes, in particular to a method for determining dredging sites of overwintering cyanobacteria provenance in large shallow lakes. Background technique [0002] Eutrophication of water bodies leads to polluting scarcity of fresh water resources. The abnormal reproduction of cyanobacteria and the formation of algal blooms are one of the most important signs of lake eutrophication. At present, many researchers have realized that the formation of algal blooms in summer has an important relationship with the overwintering cyanobacteria in lake sediments in winter. For example, in Taihu Lake, cyanobacteria sink to the surface of the bottom mud to overwinter in autumn, and in the spring of the following year, the cyanobacteria recover and rise from the bottom mud surface to the water surface, providing the necessary "seed source" for the formation of algae blooms. Based ...

AI Technical Summary

Problems solved by technology

[0004] The large-scale lake dredging and dredging projects currently being carried out are mainly to reduce nutrients, remove pollutants on the surface of the sediment, or remove silt in the bay area, which is not suitable for dredging the source of overwintering cyanobacteria

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