Niti Iamchuen, Sitthisak Pinmongkhonkul, Warach Madhayamapurush
The aims of the present study were to determine trees diversity, water quantity and ecosystem services in watershed forest areas and assess the value of ecosystem production services that affect agriculture by quadrat method at forest waterhed of Huai Tat Sae, Huai Chomphu and Huai Pha Neab reservoir areas for exploring the structure of plant community and in-depth interview was used to survey production service datas for analyze the value of the production. The result found 116 species belonging to 36 families. Shanon-wiener’s Index average was 3.21. Run-off form rainfall release water to the reservoir was 3,083,437.5 m3/ year, this to support corns, longan, rice, sweet tamarind and shallots in Sun Khong sub-distrcit agricultural areas, and forest production. The economic value for ecosystem services was 5,540,431 bath/ year.