Soil environment quality hierarchical discrimination method of reclaimed land hierarchical safe utilization

Abstract

The invention discloses a soil environment quality hierarchical discrimination method of reclaimed land hierarchical safe utilization. According to the method, two soil safety thresholds based on the sanitation and the safety of agricultural products are set: the threshold I and the threshold II; three types of safe utilization approaches are specified according to the corresponding pollution risk level of the two thresholds: the priority farming area, the restricted farming area and the ecological control area; and the final value of the threshold II of the soil pollutant is determined by constructing the quantitative relation between the crop pollutant content and the soil pollutant concentration through the pot experiment. The numerical interval of the threshold I and the threshold II is large, the range of application is wide and operability is high so that the local cultivated land resources can be supplemented to the greatest extent. According to the method, the quantitative relational expression between the soil and the crop pollutant content is constructed through the pot experiment so that the reliable technical route and method can be provided for researching and formulating the localized soil environment quality standards for the reclaimed lands for all the regions by combining the local soil pollution characteristics, the land reclamation requirements, the crop planting habits and other factors.

Description

technical field [0001] The invention belongs to the technical field of soil environment quality classification, and relates to the graded and safe use of reclaimed land, in particular to a soil environment quality graded discrimination method for the graded and safe use of reclaimed land. Background technique [0002] Under the macro background that my country's social and economic development has entered a transition period, problems such as land expansion, resource shortage, environmental degradation and "big city disease" brought about by the last round of "incremental planning" in Beijing, Shanghai and other large cities are becoming more and more serious. highlight. Under the guidance of the country's development concept of promoting intensive and economical use of land and implementing total control of construction land, these large cities have gradually entered the "era of reduction", and the focus of reduction has been on the long-standing problem - inefficiency on i...

AI Technical Summary

Problems solved by technology

The current soil environmental quality standards related to agricultural land are basically not suitable for judging the safe use of reclaimed land, mainly because of the following obvious problems in the formulation of the current standards:

The current agricultural land soil environmental quality standard system evaluates and manages the soil environment as a whole, and the distinction between "exceeding the standard" and "pollution" of soil pollution indicators is not rigorous, and the assignment of various indicators is not strict, such as The Cd value is relatively strict, and the Pb value is relatively wide

In most cases, if the soil whose content of a certain heavy metal exceeds the soil quality standard for agricultural land is called "contaminated soil" (unsuitable for growing crops), this method of defining polluted soil may play an important role in the implementation of construction land reduction and rehabilitation. A lot of arable land resources are wasted during reclamation

This may hinder the effective and safe use of reclaimed land with different pollution levels in various regions and maximize the replenishment of the city's cultivated land resources

[0006] (2) The standard formulation method is flawed. The current standard mainly formulates soil environmental quality standards for "soil" itself, so as to prevent soil pollution and ensure agricultural and forestry production and human health

[0007] (3) The scope of application of the standard is flawed

The current agricultural land soil environment standard system is a "one-size-fits-all" national standard, and the threshold range of most indicators is "too narrow", which is only appropriately opened according to the range of soil pH value or farming type (paddy fields, orchards, etc.), resulting in the scope of application too small

The current standards do not take into account the differences in soil conditions, consumption habits, and edible crop varieties in various regions. As a result, when implementing the construction land reclamation in various regions, if the current agricultural land standards are used to determine the safe use of the reclaimed land , there is a problem of poor operability, because each region is greatly affected by local land policies, land use methods, agricultural development directions, crop varieties, etc.

In addition, the degree and scale of soil pollution of different reclaimed lands are quite different. The relatively single threshold range in the current standard cannot meet the actual needs of safe utilization and classified management of reclaimed construction land into agricultural land, nor can it be based on different crop varieties. The requirements for the quality of the soil environment to specify the safe use of specific plots

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