The goals of this study are (1) to maintain acid deposition network for conducting a long-term monitoring and data analysis, (2) to maintain the integrated atmospheric mercury and heavy metals monitoring network and analyze the data, (3) to establish and maintain an integrated atmospheric modeling system for studying the long-range transport of air pollutants and local air pollutants in order to assess their impact to Taiwan air quality, and further to provide fundamental information to EPA for air pollution management, (4) to revise the AQI index when extreme air pollution events occur, (5) to investigate the impact of acid rain and acidity fog to the ecosystem’s nutrient cycling, (6) to update and maintain the web site of acid rain study in Taiwan, (7) to promote international, cross-strait and southeast countries cooperation and technical exchanges on regional air pollutant transport issues. To date, our achievements are highlighted below:  The 971 samples in 14 stations all over Taiwan were collected in 2017. The average pH for all the samples is 5.31.  The situation of acid rain in Taiwan is slightly improved. Annual average pH values for most of sites are greater than 5.0. The northern Taiwan is still worse than the southern Taiwan.  The fertilization experiment result from Lian-Haw-Chih and Mt. North Tongyen Experimental Forest showed that the additional nitrogen has positive growing effect to the forest no matter at high and low altitudes. However, we need longer monitoring data to understand whether the additional nitrogen from acid deposition will still have positive growing effect to the forest or not.  The web site (http://acidrain.epa.gov.tw) of Taiwan acid rain study has been updated with more information.  We have continued to promote and participated in international collaborations and technical exchanges, for example, Quality Assurance Science Activity Center of UN, and the World Meteorological Organization Global Precipitation Chemistry and Deposition Science Assessment.  Since January 2016, the cross-strait stations, Fuzhou and Matsu have already be established to cooperate in acid deposition monitoring and data exchange. Moreover, after Prof. Lin visited Chin-Mai University in Thailand and three metrological stations in Vietnam this year, we have great chances to cooperate in acids deposition monitoring with Chin-Mai station and Yen Bai station of EANET in the future.

long-range transport, acid rain, atmospheric mercury