RU2612345C1 - Method of total soil phytotoxicity determining - Google Patents

Abstract

FIELD: ecology.

SUBSTANCE: invention relates to field of ecology, specifically to total soil phytotoxicity determination by bioindication method. For this purpose performing soil biotesting by cellulose-decomposing microorganisms activity. Soil toxicity is determined by flax linen decomposition degree with size of 5 x 10 cm in soil layers 0–10, 10–20 and 20–30 cm in one month after chemical plant protection agents application. Soil toxicity degree is determined by linen in soil decomposition intensity. With decomposition of more than 60 % of linen soil condition is estimated as satisfactory, 30–60 % is environmental risk, less than 30 % is environmental disaster.

EFFECT: invention enables to increase accuracy of contaminated territory assessment and simplify determination of its toxicity in field conditions without additional chemical analyses and can be used to assess human factor influence on biota.

1 cl, 1 tbl, 3 ex

Description

The invention relates to the field of ecology, namely to monitoring the characteristics of various ecosystems by bioindication methods, and is intended to determine soil toxicity and can be used to assess the influence of anthropogenic factors on biota.

There is a method in which the toxicity of soils and the environment is assessed by animal bio-indicators, their morphological characteristics [RF patent No. 2372617. IPC G01N 33/24. Publ. 11/10/2009. Bull. No. 31]. The known method is quite complicated, because it is necessary to identify insects moving along the surface of the soil, study their morphology, classify individuals according to the class of characters, which complicates the technical solution.

The technical solution closest to the claimed object is a method in which soil toxicity is determined by the nitrogen-fixing activity of nodule bacteria that form nodules on the root system of legumes in a 15-20 cm soil layer, 2-3 weeks after spring regrowth and before the flowering phase, and the degree of soil toxicity is determined by the internal coloring of nitrogen-fixing nodules (pink or red) and its presence in less than 50% of nodules is considered an environmental risk, and in less than 20% of nodules an environmental disaster (prototype) [RF patent No. 2490630. IPC G01 N33 / 24. Publ. 08/20/2013. Bull. No. 23].

However, the toxicity assessment is determined only in the crop rotation, where legumes occur at a strictly defined moment of their vegetation. The method used to assess toxicity cannot be used in the interval necessary for the researcher to the interval of the growing season.

The claimed technical solution is that the toxicity of the soil is determined by the activity of cellulose-degrading microorganisms that form the microbiological cenosis of the soil during a given interval of vegetation.

The essence of the proposed method consists in bioassay for the activity of cellulose-degrading microorganisms. Toxicity of the soil is determined by the degree of decomposition of linen in the soil layers: 0-10, 10-20 and 20-30 cm within a month after the use of chemical plant protection products. The degree of soil toxicity is determined by the rate of decomposition of linen in the soil: when decomposing more than 60% of the linen, the soil condition is assessed as satisfactory, 30-60% - environmental risk, less than 30% - environmental disaster.

The method is as follows.

In contrast to the known method, it is possible to determine the toxicity of the soil directly at the sites according to the degree of decomposition of the linen cloth at the time necessary for the researcher.

If there is an excess of toxic substances in the soil, the acid regime of the soil solution in the root-inhabited layer is violated, which leads to a decrease in the activity of cellulose-degrading microorganisms.

With the intensity of decomposition of cellulose in the studied area, three categories of soil toxicity are determined:

1 - when decomposing more than 60% of the canvas assess the condition of the soil as satisfactory;

2 - 30-60% - environmental risk;

3 - less than 30% - environmental disaster.

In contrast to the known technical solution, soil toxicity assessment can be carried out throughout the growing season.

Example 1. In various places contaminated with toxic substances, an area of 0.5 hectares, linen sheets horizontally, vertically laid on a plastic film, are fixed horizontally vertically, fixed with a plastic film, the size of the paintings is 5 x 10 cm. The exposure is 30 days. After the expiration of the linen was removed from the soil, cleaned of lumps of soil and visually determined the degree of decomposition of linen. The degree of decomposition in the layer is 0-10 cm 30-60%. Thus, the study area belongs to the 2nd category (“environmental risk”).

Example 2. In various places contaminated with toxic substances area of 0.2 ha, horizontally, horizontally, vertically laid linen sheets that are mounted on a plastic film, the size of the paintings 5 x 10 cm. The exposure time is 30 days. After the expiration of the linen was removed from the soil, cleaned of lumps of soil and visually determined the degree of decomposition of linen. The degree of decomposition in a layer of 0-10 cm less than 30% is an environmental disaster zone.

Example 3. In various places contaminated with toxic substances, an area of 0.4 hectares, linen cloths fixed horizontally vertically are fixed vertically on a plastic film, the canvas size is 5 x 10 cm. The exposure is 30 days. After the expiration of the linen was removed from the soil, cleaned of lumps of soil and visually determined the degree of decomposition of linen. The degree of decomposition in the layer of 0-10 cm is more than 60% - the condition of the site is satisfactory.

The results of the experiments are shown in the table.

Table - Assessment of soil toxicity by the rate of decomposition of cellulose,%

Option Soil layer, cm Site Condition 0-10 10-20 20-30 Soil I more than 60 45-50 35-40 satisfactory Soil II less than 30 15-20 5-10 environmental disaster Soil III 30-60 25-30 15-20 environmental risk

Technical result: the proposed method improves the accuracy of the assessment of the contaminated area and simplifies the determination of its toxicity by the activity of cellulose-degrading microorganisms in the field without additional chemical analyzes.

Claims (1)

A method for determining the total phytotoxicity of the soil, including bioassay on the activity of cellulose-degradable microorganisms, characterized in that the phytoxicity of the soil is determined by the activity of cellulose-degradable microorganisms according to the degree of decomposition of linen linen 5 × 10 cm in soil layers 0-10 cm, 10-20 cm, 20-30 see, a month after the application of chemical plant protection products, and the degree of phytoxicity of the soil is determined by the rate of decomposition of cellulose, and when decomposing more than 60% of the linen, the conditions the soil is satisfactory, 30-60% - as environmental risks, and less than 30% - as an ecological disaster.