Abstract:
The thesis was to verify the validity of the acid deposition model prediction for the year 2000 using RAINS-Asia and ATMOS2. The monitoring sites of 6 provinces namely Ayuttaya, Chaingmai, Chonburi, Nakornpratom, Nakornrashasima and Songkla were selected from 6 regions of Thailand. The data collected from the 6 sites were used for comparing the quantity of acid deposition with the ATMOS2 and RAINS-Asia models. The results of the comparing analyses showed that the ATMOS2 model provided better predictions than the RAINS-Asia model. The prediction value using the ATMOS2 compared with the 6 monitoring sites had shown percentage error of +46, -76, -107, +45, -8 and +49, respectively. While the RAINS-Asia model prediction had shown percentage error of +57, +47, -107, -66, +13 and +59, respectively. Hence the ATMOS2 model by this study is more appropriate to be used as a tool to estimate the amount of acid deposition in the future. The study was also extended to determine the effect of acid deposition in Thailand by comparing the monitoring data with the critical load value. The results showed that Chaingmai province had a higher risk than other regions which caused by the amount of acid deposition in the areas. The amount of acid deposition in this province was measured to be 142 mgS/m2.yr but the soil characteristic of this region can accept the amount of sulfur deposition not to exceed 50 mgS/m2.yr.