The following article is a literature survey of water management interventions taken up in Indian fields to improve the water productivity which would in turn reduce the groundwater decline.
The authors of this article through an extensive literature survey, are able to put together a list of measures that have been tested to reduce the evapotranspiration in fields. According to the authors, scientists at the Punjab Agricultural University (PAU) analysed the water balance for the state of Punjab and found that water supply fell short of demand by 40%. This was a wake-up call to those concerned with planning long water use.
Later a study by the Punjab State Farmers Commission estimated that the aquifer level declined by about 4.7 m between 2001 and 2006 against 0.6m from 1980 to 1985. The implications of this include increase in cost of agriculture to threatening sustainability of cropping systems. Due to this water shortage, the authors feel, that the emphasis should be on maximising returns per unit of water consumption with minimum social and ecological impact.
The article is divided into strategies for reducing water loss in assured water regions and strategies for areas with limited water supply. The authors highlight the benefits of using mulch, drip irrigation, bed planting, seeding at right time, proper tillage for the former. In case of the latter the authors point out to the need to find suitable crops based on timing and magnitude of water availability. Inputs like fertilisers and small supplementary irrigation are also key to enhance water productivity in such regions.
The article can be downloaded from the Current Science website here.