Method for obtaining regional estuary nutrient reference value

Abstract

Accoridng to the method provided by the invention, based on the difference of each estuary in the aspects of salinity, hydraulic retention time, runoff, tide, biological conditions and the like, the nutrient level and eutrophication effect of the estuary also have great regional difference, and according to the characteristics of different estuary areas and different types of water bodies, the difference of the sensitivity of different estuary ecosystems to nutrients is studied, and the estuary is classified; on the basis, a fuzzy comprehensive evaluation model is adopted to evaluate the health condition of the estuary ecosystem and find the state of a reference point. A benchmark making method is determined according to the state of the reference point and the health condition of the ecosystem; a frequency distribution method, a historical record analysis method, a columnar sediment analysis method and a pressure-response model method (including a linear regression model method, a classification regression tree model method, a Bayesian inflection point analysis method and a non-parametric inflection point analysis method) are respectively adopted to establish a nutrient referencethreshold value of the estuary.

Description

technical field [0001] The invention relates to the technical field of environmental protection, in particular to a method for obtaining regional estuary nutrient benchmarks. Background technique [0002] The estuary nutrient benchmark is the scientific basis for the assessment, prevention, control and management of eutrophication in the estuary; it is the basis for the unified management of the environmental quality of the estuary. As an important part of the water quality benchmark, the estuary nutrient benchmark has an important scientific and practical significance. At present, the United States, the European Union and other countries have issued technical guidelines for formulating estuary nutrient benchmarks for eutrophication prevention and control and nutrient benchmarks based on technical guidelines. Eutrophication in the United States is also a long-standing problem. In order to prevent eutrophication, the U.S. Environmental Protection Agency (U.S.Environmental Pr...

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Problems solved by technology

[0003] So far, there are no technical normative documents on estuary nutrient benchmarks in my country, and there is no scientifically standardized process and method for formulating estuary nutrient benchmarks, let alone nutrient benchmark values ​​for different types of estuaries to reflect the differences in estuary nutrient status.

Moreover, my country's existing water quality standard system is not perfect. The existing standards related to nutrient indicators include "Surface Water Environmental Quality Standards" (GB 3838-2002) for freshwater waters and "Sea Water Quality Standards" for seawater waters. "(GB3097-1997), but there is no standard for estuary areas with mixed salty and fresh water, and due to the differences in salinity, hydraulic retention time, runoff, tide, biological status, etc. of different estuaries, the current water environment quality standards are not Applicable to all estuaries and cannot meet the needs of estuary environmental management, resulting in "under-protection" and "over-protection" of different estuary environments to some extent

[0004] At present, there is no standardized process and method for formulating estuary nutrient benchmarks in my country, and there is no standard system for the mixed salty and fresh water areas of estuaries

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