Ecosystem responses and behaviors under changing pressure of air pollutants: Special article collection from the 10th International Conference on Acid Deposition “ACID RAIN 2020”

This special issue is a partial compilation of research papers from the 10th International Conference on Acid Deposition “ACID RAIN 2020” conference held in Niigata, Japan in April 2023, focusing on ecosystem responses to air pollution. The Acid Rain Conference series began in 1975, initially addressing the harmful effects of acid deposition on ecosystems. Over time, the research focus evolved from simple acid rain issues to effects of excess nitrogen deposition and saturation in the 1980s, and then to ecosystem recovery studies in the 1990s. Current research examines interactions with climate change and air pollution in developing countries. The special issue contains 11 papers: eight on long-term ecosystem responses, two on plants' role in reducing air pollution, and one technical note on soil sampling in biogeochemical monitoring. The long-term studies, from Japan and Norway, show different regional responses to acid deposition. Japanese forests demonstrate higher acid buffering capacity than Northern European ones, partly due to the composition of volcanic soil. Nordic papers focus on modeling tools, MAGIC (Model of Acidification of Groundwater In Catchments), which has been improved over time to simulate the combined effect of acid deposition and climate change impacts. It is significant that exactly half a century after the first conference, this collection of contemporary papers will be published in Ecological Research. This is because findings from research on biogeochemical cycles in ecosystems related to acid rain should be widely shared among the ecological community, and through this, a variety of audiences should be informed.