The main principle that drip irrigation can control soil salinization is that drip irrigation needs less water, so the amount of inorganic salts in water will be relatively reduced, and the saline-alkali substances produced by water evaporation will be much less than irrigation, which will be more conducive to controlling soil salinization. However, it should be noted that this can not fundamentally solve the problem, but can only relatively delay soil salinization, because with the evaporation of water, saline-alkali substances will still accumulate.

Soil salinization means that the soil salt content is too high (more than 0.3%), which makes crops low-yield or unable to grow.

There are two conditions for the formation of saline-alkali soil: first, the climate is dry and the groundwater level is high (above the critical water level); The other is low-lying, with no drainage outlet. Groundwater contains a certain amount of salt. For example, its water surface is close to the ground and the area is relatively dry. After the water rising to the surface evaporates due to capillary action, salt is left: over time, the salt content of soil gradually increases, forming saline-alkali soil; If it is a depression and there is no drainage outlet, the water in the depression will evaporate, leaving salt and forming saline-alkali land.

Adverse effects:

1, soil hardening, fertility decline.

2. It is unfavorable for crops to absorb nutrients and hinder crop growth.

Prevention and control:

Measures to control saline-alkali land include water conservancy improvement measures (irrigation, drainage, silting, rice planting, seepage prevention, etc.). ); Agricultural improvement measures (leveling land, improving farming, applying exotic soil, fertilizing, sowing, crop rotation, interplanting, etc.). ); Biological improvement measures (planting salt-tolerant plants and pasture, green manure, afforestation, etc.). ); And chemical improvement measures (using gypsum, phosphogypsum, calcium sulfite and other improving substances. ). Four aspects. Because each measure has a certain scope of application and conditions, it must be treated comprehensively according to local conditions.