METHOD FOR ASSESSING QUALITY OF DRAINAGE WATER FROM IRRIGATED LANDS Russian patent published in 2024 - IPC G01N33/18 

FIELD: environmental protection.

SUBSTANCE: invention relates to environmental protection, particularly water bodies, and can be used for environmental assessment of quality of drainage water (DW) from irrigated lands diverted into water bodies. Method consists in the fact that a complex indicator of the quality of drainage water is calculated as a sum of integral indicators. Integral indicators are responsible for: geochemical background of the territory of the basin of the water body or its section, salinization, supply of residual amounts of fertilizers and pesticides. To determine the integral indicator responsible for the geochemical background of the territory of the basin of a water body or its section, excess of actual concentrations in the outlet of hydrocarbonates, sulphates, calcium and magnesium ions over their background values in the water intake is taken into account. To determine the integral indicator of water salinity, actual concentrations of sodium and chloride ions are taken into account. To determine the integral index responsible for the pesticide intake, biochemical oxygen consumption for five days is taken into account. To determine the integral indicator responsible for the supply of residual amounts of fertilizers, average arithmetic excess of content of ammonium ions, nitrate- and nitrite-ions, phosphorus, phosphates and iron over their maximum permissible concentration. Range of values of the complex indicator and the integral indicator which is responsible for the geochemical background of the territory of the basin of a water body or its section is divided into four ranges. Values of the integrated indicator less than 13.3 characterize drainage water as clean, from 13.3, but less than 24.0—moderately contaminated, from 24.0, but less than 76.7—dirty, and from 76.7 and more—very dirty. Integral index value less than 1 characterizes drainage water as clean, from 1, but less than 1.5—as moderately contaminated, from 1.5, but less than 2—as dirty, more than or equal to 2—very dirty. Assessment of quality of drainage water from irrigated lands is determined by belonging of obtained value of complex indicator of quality of drainage water and integral indicator, responsible for the geochemical background of the territory of the basin of the water body or its section, corresponding to the range.

EFFECT: reliable integral assessment of drainage water quality proceeding from non-damage to water body into which drainage water is discharged.

1 cl, 5 tbl, 1 dwg