アグロテクノロジー

概要

Irrigation Performance Assessment of Left Bank Canal, Nagarjuna Sagar Project, India During Rabi Using Remote Sensing and GIS

Avil Kumar K

An Investigation on irrigation performance assessment of Mudimanikyam and Janpahad major, Left bank canal, Nagarjuna Sagar Project (NSP), Andhra Pradesh, India using remote sensing and GIS was carried during rabi (2008-09 and 2009-10) at Water Technology Center, ANGRAU, Rajendranagar, Hyderabad. Multi temporal remote sensing (RS) data-based crop inventory and Normalized Difference Vegetation Index (NDVI), which is very sensitive to the presence of the green vegetation and is a ratio of near infrared radiation minus red radiation and near infrared ratio plus red radiation. The NDVI was generated for Mudimanikyam and Janpahad major command of NSP, using Indian Remote Sensing Satellite (IRS-P6) Linear Imaging and Self Scanning–III (LISS-III) data. In this study, remote sensing based indicators ie., irrigation intensity( target value of 100%), water utilization index (WUI), depth of water applied, overall consumption rate (ep), relative water supply (RWS), output per unit cropped area ($/ha), output per unit cultivable command ($/ha) and water productivity (wp) were estimated for the command area. This study demonstrates how the remote sensing based estimates of crop area and production combined with water release data from project and climatic data can provide better estimates of irrigation performance. A principle benefit of the described approach is that it allows identification of areas where agricultural performance is less than potential, thereby providing insights into where and how irrigation systems can be managed to improve overall performance and increase water productivity in a sustainable manner.

These parameters varied from 92.39 to 123.19 for irrigation intensity against target of 100 per cent, 86.04 to 148.96 for WUI against the target of 141.24 ha Mcum-1 of wet crop, 0.40 to 0.80 for ep, against target of 0.56, 0.42 to 0.75 for RWS against target value of 2.0 and 0.152 to 0.203 for wp against value of 0.35 kg m-3 during rabi 2008-09 and 2009-10, respectively. These performance indicators showed that irrigation performance of Janpahad major was better than Mudimanikyam. The ep indicators for the majors during rabi 2009-10 were lower (0.40 and 0.52) than the target value and WUI was higher for Janpahad major during both the years.