Buncha Apai. An integrative agricultural land evaluation and classification for sustainable land-use in Uthai Thani province. Master's Degree(Technology of Environmental Management). Mahidol University. : Mahidol University, 2003.
An integrative agricultural land evaluation and classification for sustainable land-use in Uthai Thani province
Abstract:
This study investigated and evaluated the suitability of agricultural land use taking into account
physical, socioeconomic and environmental conditions of the study area. A soil conservation-oriented
land use planning technique using Geographic Information System (GIS) technology together with
Two-stage Land Evaluation Approach, Universal Soil Loss Equation (USLE), macro nutrient loss
assessment, and linear programming were conducted in Uthai Thani Province of Thailand.
Physical land suitability evaluation for major present and alternative land utilization types was
performed. Predicted potential soil erosion (PE) and actual soil erosion (AE) volume in agricultural
land under present land cover management and alternative crop types were measured. Then, the
predicted actual soil loss together with nutrient availability data of each soil type were used to calculate
the macro plant nutrient loss in the form of Urea, Super Phosphate, and Potassium Chloride in each soil
series under alternative crop types. The overall land suitability assessment using linear programming
was conducted using two postulates - minimizing macro nutrient loss while maintaining current levels
of average net farm income and maximizing net farm income while not exceeding current levels of
macro nutrient loss.
Results of the study indicate that even though most of the soil types in the study area are not fertile,
changing farming patterns from intensive mono-crops to fruit trees may provide more profitable and
sustainable returns in approximately 25% of the total agricultural area. Some alternative crops including
coffee, cocoa, vegetables, and rubber would not be recommended for the study area because of severe
limitations of the soils. The study results also indicated that approximately 41,500,000 tons of soil are
annually lost from agricultural land of the province with 8.95% and 4.52% of the area under severe and very
severe erosion while the total actual losses of urea, super phosphate, and potassium chloride were estimated
at 90,005.70, 2,761.96, and 7,394.57 tons/year respectively. The most suitable crop combination to
minimize macro nutrient loss while maintaining the average levels of net farm income is suggested as
wetland rice, maize, sugarcane, cassava, and pineapple at the proportions of 2.72%, 54.90%, 0.45%,
19.54%, and 22.40% of total agricultural area respectively while the most suitable crop combination to
maximize net farm income while not exceeding the current level of macro nutrient loss is wetland rice,
maize, sugarcane, cassava, and pineapple at 1.16%, 42.49%, 1.11%, 19.95%, and 35.29% respectively