Abstract:
The main objective of this study is to investigate the optimal cropping pattern in order to develop guidelines for agricultural development planning at the Huay Khow San watershed in Ubon Ratchthani province. Due to variation of geographical, social and economic conditions, the cropping patterns are categorized into three zones basing on water availabilityirrigated areas throughout the year, irrigated areas in the rainy season only, and rainfed area. The present study used linear programming models to analyze the existing traditional cropping patterns and the cropping patterns with new crops included. The study also cover a series of sensitivity tests on changes of constraints of factors of production as well as changes of farm prices. From the findings of the analysis, appropriate cropping patterns are recommended. It is recommended the farmers should, in each season, grow crops in each zone as follows. In the rainy season, they should grow non-glutineous and glutineous rice. The non-glutineous rice would be for sales and glutineous rice for own-comsumption. The planting area should be 26.62 rai. As for the dry season, the farmer who have access to a weir in the village should d[i]vided the area along the stream into sections for growing crops after rice harvest. For each farm an average of 2.88 rai should be allocated to grow corn. With this typed of cropping pattern: it is possible to obtain a net farm income of 10,199.631 baht. In the case of new crops such as field chilli are introduced in dry season after rice harvest and with a planting area of 2.88 rai, the net farm income can be increased to 20.249.68 baht. However, the sensitivity tests which were performed by changing factors of production show a [substantial] variation in net income, especially in the case of changing the size of planting area. The sensitivity tests performed by reducing the farm-gate price of chilli show that it is necessary to reduce the planting area of chilli and substitute the reduced area by growing corn, groundnut or soybean. In all these cases, the changing of farm-gate prices of these crops would effect the appropriate cropping patterns greatly. The study also finds out that by employing farm labor in dry season in the area with sufficient water from the stream could lessen the problem of seasonal employment and migration to some extent.