This work aims at assessing changes in saltwater intrusion in main rivers located in Dong Nai province. The results indicated that Long Thanh and Nhon Trach districts have been affected by saltwater intrusion with the highest salinity concentrations of about 26-28 ‰. The salinity level during the dry season is higher than that in the rainy one and the salinity boundaries of 1 ‰ and 4 ‰ gradually extend towards inland water. | TAÏP CHÍ PHAÙT TRIEÅN KH&CN, TAÄP 19, SOÁ T6- 2016 Assessing changes in saltwater intrusion in main rivers of Dong Nai province and the adaptive capacity of the communities Van Bang Nguyen Xuan Hoang Tran Institute of Meteorology Hydrology Oceanology and Environment Ngoc Tuan Le University of Science, VNU–HCM (Received on 17th December 2015 Accepted on November 21th 2016) ABSTRACT Saltwater intrusion, which is a natural process, is strongly influenced by climate change, and almost negatively affects the lives and livelihoods of communities. This work aims at assessing changes in saltwater intrusion in main rivers located in Dong Nai province. The results indicated that Long Thanh and Nhon Trach districts have been affected by saltwater intrusion with the highest salinity concentrations of about 26-28 ‰. The salinity level during the dry season is higher than that in the rainy one and the salinity boundaries of 1 ‰ and 4 ‰ gradually extend towards inland water. Besides, adaptive capacity (AC) to saltwater intrusion in Bien Hoa city, Long Thanh and Nhon Trach districts was surveyed and assessed by the AC indices. By assessing AC of local government and communities against 19 criteria, Nhon Trach district showed its high AC meanwhile AC of Long Thanh and other districts were moderate and low, respectively. This research also indicates limitations of each locality, an important basis for proposing solutions to improve AC to saltwater intrusion for the communities. Keywords: saltwater intrusion, adaptive capacity, adaptive capacity index, climate change INTRODUCTION In the context of climate change (CC), rivers are greatly affected by the fluctuations of temperatures, rainfall, sea levels, etc. including saltwater intrusion (SI). SI alters water quality, as the result, most relevant activities, such as agriculture, farming, aquaculture, services, etc. of the coastal area are impacted. There have been many worldwide studies on SI and SI influences. In Vietnam,