Energy audit of rice production systems in different land forms in mid hills of Arunachal Pradesh

A field study was carried out in four land forms of rice cultivation namely wetland (WRC), terrace wetland (TRC), upland (URC) and jhum land (JRC) in mid hills of Arunachal Pradesh during 2009 and 2010 to assess the energetics of rice cultivation in various land forms. It was found that the labour requirement was highest on JRC (122 man-days ha-1) and least on URC (75 man-days ha ha-1), whereas, the machine energy was required maximum on TRC (2015.58 MJ ha-1). The highest seed rate (80 kg ha ha-1) was used on URC followed by JRC (50 kg ha-1). The fertilizer use was higher on WRC land form whereas, lower on URC. Uses of pesticides were higher on URC. As only traditional practices were followed by farmers, fertilizers and pesticides were not used in JRC. Total output-input energy ratio and energy productivity was recorded higher on JRC (17.67% and 0.45 kg MJ-1, respectively) followed by WRC (13.86% and 0.38 kg MJ-1). However, specific energy was recorded maximum on URC (3.43 MJ kg-1) and least on JRC (2.21 MJ kg-1). Nevertheless of higher cost for inputs, the net return and B:C ratio was higher on WRC followed by TRC form of rice cultivation.