Study sites

The study sites were established in four forest catchments in Japan, Thailand and Malaysia. Fluxes of ions including SO₄²⁻ had been studied by previous projects since 2002, 2005 and 2008 in Kajikawa, Sakaerat and Danum Valley sites, respectively. However, the surveys in these sites were mostly finished in 2010/2011. In 2012, the study sites were reactivated for the APN project and the rehabilitated forest in Bintulu was added as a new site for the APN project.