Water logging and soil salinity are some | Class 12 Biology Chapter Environmental Issues, Environmental Issues NCERT Solutions

Waterlogging is the saturation of soil with the water, i.e. known as soil may be waterlogged. When it is saturated with water, then the air phase is restricted and anaerobic condition is operated instead of using aerobic condition. And, soil salinity is defined as the salt content in the soil and the process of increasing salt is known as salinization. Both problems have come in the wake of the green revolution.

Causes:-

1. Waterlogging is caused by the excess rainfall, poor drainage system and the inability of the soil to hold the excess amount of water.
2. Heavy clay soils like black cotton soils which holds the moisture for the long time, means they become waterlogged easily.
3. Main reason of waterlogging is irrigation if not well planned and by this, drainage problems can turns into worse.
4. Salinization can caused by the use of salt rich irrigation water, poor drainage system etc.

Adverse effects:-

1. Waterlogging lowers the oxygen level (locked the air spaces in the soil) and uses anaerobic condition which reduces the plant growth.
2. Salinization affects the crops production, reduces growth, some ions which are toxic to the plants and when these ions concentration increases then the plants dies off.