Correct Option
Micro-irrigation systems, such as drip and sprinkler irrigation, deliver water and dissolved nutrients directly to the plant root zone. This precise application significantly reduces losses of fertilizers and nutrients through leaching, runoff, and evaporation, thereby enhancing nutrient use efficiency.
By optimizing water delivery and reducing overall water consumption compared to traditional methods, micro-irrigation helps prevent the over-extraction of groundwater. This can effectively contribute to checking the receding groundwater table in agricultural regions where water resources are under stress.
Incorrect Options
While micro-irrigation is highly beneficial and suitable for dryland farming due to its water-saving characteristics, it is not the exclusive method of irrigation in such areas. Other practices like rainwater harvesting, contour bunding, mulching, and traditional tank irrigation are also employed in dryland agriculture to conserve moisture and provide water. Therefore, the assertion that it is the "only means" is incorrect.