| Abstract | Rice production in Thailand plays an important role by providing domestic food security as well as earning an export income. Though rice is not the economically dominant crop in the southern region of Thailand, it constitutes the main source of livelihood for small farmers in the region since historic times. More importantly, rice-based farming system in the southern region in particular, is confronted with a host of operational constraints ranging from socio-economic to environmental degradation issues, questioning the viability and sustainability livelihoods of the rice based farmers. Marked differences are also observed in productivity of farms as the rice farmers are heterogeneous in terms of their livelihood assets and resource endowments. This research was assessed the sustainability livelihood farmers from three perspectives: environmental, social and economic. The vulnerability context, transformation structure and process affecting rice-based farming system were studied and attempted to examine the livelihood assets of rice-based farmers by developing scales and constructing livelihood asset pentagons. Finally the appropriate models of rice-based farming are proposed in order to meet the condition of sustainable livelihood system. The study was undertaken in Phatthalung province, on the east coast of the southern region of Thailand. Based on the topographic situation and water availability, the rice-based farming system was classified into three agrosystems (AS), viz. a) Agrosystem I (ASI); b) Agrosystem II (ASII); and c) Agrosystem III (ASIII). ASI is a lowland rice-based farming system where year round water is available through irrigation schemes, which enables double rice cultivation. ASII includes lowland rice-based farming system where water is supplied by irrigation schemes but not sufficient for dry season rice. Instead, dry season crops are grown in dry season. ASIII is lowland rainfed area where wet season rice is grown and the fields are left fallow during dry season. The study covered a sample of 294 farmers by using multistage sampling procedure and structured questionnaire was used for interviewing the selected farmers. Key informants interview, group discussion, secondary data and researcher observation were also done. Analytical tools employed include descriptive statistics, weighted average index construction, correlation and multiple regression analysis. In the assessment of environmental sustainability it was found out that major source of nutrients are chemical fertilizers. Few farmers add organic matter in their rice field and improper crop residues management was observed. Farmers' perceived that the trend of soil fertility is decreasing. In ASI, chemical fertilizers has been increasing over the years, the average actual use fall into the recommended rate while in ASII and ASIII the actual rate of chemical fertilizer used is still lower than recommended rate. Most of the pesticides used are classified as moderately hazardous and some banned pesticides which are extremely hazardous are still using in the area. Pesticides are widely used in ASI and all farmers used herbicides for weeds control. The actual application rate of pesticides mostly falls into the recommended rate. Farmers in ASII and ASIII do not apply much pesticide in their rice field. However, pesticides are used for pest control in dry season crops in ASII and the actual rate is often over the recommended rate, while in ASIII small rate of pesticide is used for rice field crab control. ASI is the only area where there is control of water for rice production. Farmers have not realized the scarcity of water resource because they believe that water is not exhaustible, thus most of them disagree with water saving for agricultural activity. In terms of social sustainability, the study revealed that the area has achieved food grain self sufficiency and have surplus for supplementary income. It was found out that government extension agents are responsible for the dissemination of knowledge and technologies to farmers. However, contact between extension workers and farmers are still weak, thus, the satisfaction with extension services are rated very low. The agricultural marketing services for both inputs and products are convenient. Nevertheless, price of rice grain is rather low compared to inputs price, particularly chemical fertilizers, pesticides, fuel, and wage rate. There are many forms of farmers' organization in the area which encourage farmers to help each other and for self reliance, but these objectives have not been achieved yet because members lack understanding of group principle and little sense of ownership. The economic analysis showed that farmers in ASI earn the highest net farm income while farmers in ASIII earn the lowest income. The measurement of farm efficiency revealed that wet season rice production in ASI had the highest physical and financial efficiency. Wet and dry season rice production in ASII had higher physical efficiency in term of productivity than wet season rice in ASIII but had lower financial efficiency due to lower price of rice yield. The determinant of rice yield in- regression model revealed that nitrogen fertilizer had direct positive effect on rice yield in all ASs. Phosphorus fertilizer and amount of water were also determining factors for rice yield increase in ASI. Age of farmer had the negative effect to rice yield in ASII. Herbicide application, labor used for thinning and replanting also determined rice yield in ASIII. The result of the study revealed that natural shocks including flood and drought, the transfer of technologies, development of urban area, and availability of household labor as well as inputs and productions price are the main factors that encouraged the adjustment of rice production systems. In the livelihood assets measurement, it was found that farmers in ASI have access to the highest human, natural, physical and social assets while farmers in ASII have access to the highest of financial asset. On the other hand farmers in ASIII have lower access to livelihood assets in all aspects. Five explanatory variables under natural, social and physical assets including cropping intensity, water potential, participation with groups, access to agricultural information, and access to farm machinery have been found to be critical factors determining the rice productivity. It is evident from the overall analysis that ASI is more vulnerable in environmental sustainability than others, thus the sustainable livelihood need to focus on soil, water and pest management. Rice production in ASII and ASIII generate only a small proportion of household incomes. In other word it is not sustainable in economic point of view, so other farm activities such as livestock production, dry season crops and off farm activities have the potential to earn more income. In terms of social and institutional aspect, the support service should provide effective extension and training as well as strengthen farmers' organizations in order to sustain rice-based farmers' livelihood. |