Based on the long-term surveys over 16 years in a forested catchment (Kajikawa site) located on the Sea of Japan side and analysis of the monitoring data by the Ministry of the Environment of Japan, it was found that Japan’s forested catchments have sensitively responded to air pollution. The study was conducted by Asia Center for Air Pollution (Sase H, Ohizumi T, and Morohashi M), Niigata Prefecture (Saito T and Takahashi M), Forestry and Forest Products Research Institute (Yamashita N), Kanazawa University (Inomata Y), and Niigata University (Nakata M).
- S input via atmospheric deposition started decreasing after 2006/2007, reflecting SO2 emissions in China.
- Japan’s inland water chemistry changed significantly with S input, and started recovery from acidification with decease in SO42– concentrations.
- As climatic changes may slow the recovery from acidification, it is important to understand S dynamics in ecosystems.
- River water NO3– concentration is increasing, and N deposition and other factors, such as the maturation of the planted trees, may play an important role.
These results are published in the international academic journal, Atmospheric Environment:
Sase et al. 2021. Transboundary air pollution reduction rapidly reflected in stream water chemistry in forested catchment on the Sea of Japan coast in central Japan. Atmospheric Environment, in Press.
This work was conducted as one of the Network Center research activities for Acid Deposition Monitoring Network in East Asia (EANET). Part of the data in this study was obtained from the long-term monitoring on transboundary air pollution and acid deposition of the Ministry of the Environment of Japan. Also, this work was supported by grants from the Asia‐Pacific Network for Global Change Research (ARCP2012‐18NMY‐Sase; ARCP2013‐13CMY‐Sase) and the Japan Society for the Promotion of Science (JSPS) KAKENHI Grant Numbers JP19H00955, JP19K12315 and JP18K11616
The full text can be downloaded from the following link (open access):
Research outputs on Kajikawa site and relevant catchment sites can be found in the following link:
Catchment Studies in Kajikawa Study Site and Lake Ijira Monitoring Site