A Development of Thai Soil Database for SWAT Model

Abstract

This study prepares Thai soil database for SWAT model. The Mea Chaem basin, Chiangmai, and Upper Huai Luang basin, Udon Thani, are employed as the test areas. The daily and monthly runoff estimated from SWAT using the proposed Thai soil database and the FAO soil database is compared. The results show that hydrographs estimated from both soil databases are similar while using FAO soil database provides slightly reliable than using Thai soil database. Since some parameters of Thai soil database have not collected, the estimation using relationship of those parameters with other basic parameters is then applied. In addition, there are no data in the high slope area, the soil properties in vicinity is then employed. Then, for more reliability of Thai soil database, the further investigation for soil survey and its properties test are required. The established Thai soil database in Microsoft Excel format name ThaiSoilSeriesSWAT.xlsx is online published at https://engineering.rmutl.ac.th/civil/page/swat-thai-database/.