The impact of climate change on food security and agricultural production in the Pak Phanang River Basin, Thailand

Abstract

The Pak Phanang River Basin used to be an important rice growing area in southern Thailand. However, the environmental changes in the area decreased the rice planting there because of a lack of fresh water and salt water intrusion. This area was selected as one of the King of Thailand's initiative projects in 1978 to restore land fertility, improve food security, and increase the quality of the life of local people. The basin consists of three provinces covering 13 districts (amphoe): Pak Phanang, Chian Yai, Chaloem Phra Kiat, Hua Sai, Cha-uat, Ron Phibun, Chulabhorn, Lan Saka, Phra Phrom and Amphoe Mueang Nakhon Si Thammarat in Nakhon Si Thammarat Province, Khuan Khanun and Pa Phayom in Phatthalung Province, and Ranot in Songkhla Province. The total area of the basin is approximately 304,000 ha, including 80,000 ha of paddy fields. The total population of the area is about 1.2 million people. The objectives of the research were to study the impact of climate change on rice production in the basin, to find suitable areas for rice production, and to discuss food security for the area. It was found that the concrete impact of the El Ninõ and La Ninã phenomena on rice production in the study area was not clear. The study of the rice consumption in the basin showed that the demand for milled rice for local consumption was approximately 114,005.63 tons per year, derived from 172,735.80 tons of unhusked rice or raw rice. The study of land suitability for paddy rice showed that two levels of land suitability were found, including high and medium suitability. The estimation of the production capability for unhusked rice was 182,516.37 tons per year. It was found that the food security regarding rice was low because the yearly difference between production and consumption was only 9,780.57 tons, which could be used in less than one month as reserve consumption in the following year. The study of the effects of drought in the area showed that the higher elevations indicated higher drought risk because the loss of water at higher elevations was faster than at lower elevations in terms of water drainage and evaporation processes. Five levels of drought risk were classified: Very high risk (elevation higher than 20 m), high risk (elevation between 16-20 m), moderate risk (elevation between 11-15 m), low risk (elevation between 6-10 m), and very low risk (elevation less than 6 m), which covered the areas of 0.06%, 0.27%, 3.57%, 13.23%, and 82.87%, respectively. © 2017 IEEE.