ABSTRACT
Data and National Statistics .............................................................. 167 5.7 Comparative Analysis of Irrigated Areas of GIAM and Irrigation
Statistics of the MoWR ................................................................................. 167 5.8 Causes for Differences in Irrigated Areas of GIAM and National
Statistics ........................................................................................................ 171 5.9 Way Forward for Mapping of Detailed Irrigated Areas in India-GIAM
Experience .................................................................................................... 171 5.10 IAMRS for India .......................................................................................... 172 5.11 Need for Harmonizing of Irrigated Area Statistics ...................................... 173 5.12 GIS-based SDSS ........................................................................................... 173 5.13 Conclusions ................................................................................................... 174 Acknowledgments .................................................................................................. 174 References .............................................................................................................. 175
India continues to be a predominantly agrarian economy with the majority of its population depending on agriculture for their livelihood. The contribution of the agriculture sector is about 25% of the gross domestic product (GDP). India, with a geographical area of about 328 Mha, experiences diversified climatic conditions. Spatiotemporal variability in rainfall and the availability of groundwater resources have a direct impact on the irrigation system of the country. In the last 50 years, there has been a phenomenal expansion in irrigation development in India, resulting in an increase in gross irrigation area from 22.5 Mha in 1951 to about 76.3 Mha by the end of the year 2001 [1]. At the same time, the Net Irrigated Areas (NIA) in the country has increased from 21.2 Mha to about 57.2 Mha. India has about 27.5% of the global Gross Irrigated Area (GIA), which is second only to China with a corresponding ratio of 31.5% [2,3]. Many experts opined that, to meet the ever-increasing demand of the food grains in the country, a major contribution to the increase in production is attributable to the expansion of the irrigation facility. As per the estimates of the Ministry of Agriculture (MoA), a 1% increase in the irrigated area would increase production by 4 million tons (if the area and production technology and fertilizer use increase at the same rate as in the recent past). Keeping in view the importance
of irrigated agriculture in the national food production, the dynamics of irrigated areas needs to be monitored periodically in order to map the irrigated areas for their effective management. The complexities are more in mapping irrigated areas in India, where subsistence agriculture, diversity in crop types and calendar, and small landholdings prevail.
