Water Logging

What is it?

Waterlogging is the lower in land productivity through the rise in groundwater close to the soil surface, and also where the water table rises above the surface. The raised water table results in the soils becoming waterlogged and air spaces in the soil are filled with water, and plant roots, in effect, suffocate from the lack of oxygen, limiting plant growth in those areas.

Where does it occur?

Water logging occurs where bad irrigation methods are used and in poorly drained soils where water can't penetrate deeply. For example, there may be an impermeable clay layer below the soil. It also occurs on areas that are poorly drained topographically. Worldwide, about 10% of all irrigated land suffers from water logging. Currently Victoria has 1.8 million ha affected by waterlogging. Waterlogging occurs mostly on flat floodplain areas or gently sloping landforms with high rainfall and red duplex or heavy clay soils.

What causes it?

Water logging is caused by excessive irrigation on poorly drained soils, i.e. water enters the soil faster than it drains away. It occurs even worse where there is compaction of subsoil layers; where water quickly enters the topsoil but is then blocked by a water-resistant clay layer, which may occur naturally or may be induced through excessive use of agricultural machinery. Irrigation water and/or seepage from canals eventually raise the water table in the ground.

What are the impacts?

Water logging causes:

* Damage to the soil structure.

* Suffocation of Plant roots.

* Fall of productivity by about 20% in those areas affected.

* Pasture