Model answer
Water use efficiency is the ratio of water used for plant metabolism to the water lost by plant through transpiration. It can be understood as a measure to reduce water wastage from plants by providing only the necessary amount.
Role of micro-irrigation in increasing water-use efficiency
•Reduces excess water accumulation:
In micro-irrigation, the water needed for the plant to grow is given in right amount so as to reduce wastage.
•Recycling of expelled water:
In micro-irrigation system such as greenhouse farming, the plant canopy is covered in plastic to prevent transpiration water from escaping. The water is then diverting back to the plant. This will ensure that water wastage from plant will be lower in comparison to the input.
•Reduces run-off:
Water irrigation in conventional methods like canals and tube well will result in water runoff from the fields without getting utilised. This will contribute towards wastage. In micro-irrigation techniques, water will be targeted at the root of the crops so that wastage is as low as possible.
Way forward:
It is necessary to device methods to make water use efficiency high and address shortage of water across the globe.
Thus, micro-irrigation is a very important idea when it comes to sustainable use of water resources. The initial investment once recovered will make agriculture a profitable venture.
