Investigation of carbon equivalence and land requirement for rice cultivation-a case study in Thailand

Abstract

This paper was aimed to evaluate the unit amount of the carbon equivalence emitted from Thailand's rice cultivation, including tillage, fertilizer application, watering, and harvesting which are thought to be one of major constituents causing a global warming. The appropriate and specific ways to reduce the carbon dioxide emission were also introduced here. As a result from the field investigation, the highest carbon emission was occurred due to fertilizer application in the irrigated area with the average amount of 278.7 ± 56.62 kgC/ha from the applied rate of 239.4 ± 48.56 kg/ha. Also, the maximum paddy yield could be achieved in the irrigated area with the average productivity of 4,706.25 ± 1765.25 kg/ha that was converted to the average C-equivalence value 1,882.5 ± 702.50 kgC/ha. Taking the rice grain produced for the past twenty years with the annual consumption of Thai citizens into account, the unit land area required for rice cultivation was potentially decreasing from 0.089 to 0.065 ha per capita. We suggest the majority of agricultural land area is still needed for rice cultivation as to produce not only the staple food for Thai citizens but also the grain export in exchanging for the imported crude oil and machinery. © 2009, INSInet Publication.