講演詳細

防災・水文部門[Forest Disaster Prevention and Hydrology]

日付	2024年3月10日
開始時刻	ポスター発表
会場名	543
講演番号	PJ-48
発表題目	Heavy nitrogen deposition accelerates soil acidification in Chinese forests Heavy nitrogen deposition accelerates soil acidification in Chinese forests
所属	森林総研
要旨本文	We tested whether high N deposition increased soil acidification in Chinese forests. Soil pH decreased rapidly by 1 unit in 30 years in Dinghushan forest (about 90 km west to Guangzhou) that receives huge amounts of N deposition (50 kg N ha-1 yr-1). Soil acidification is caused mainly by proton generation associated with nitrification of N deposition (3.0 kmolc ha−1 yr−1), and plant cation accumulation stimulated by N deposition. Depletion of 667 cmolc kg−1 (1700 kmolc ha−1) acid-neutralizing capacity (sum of cations) and 38 cmolc kg−1 total base reserve (977 kmolc ha−1) are required for 1 unit drop of soil pH, but the cumulative acid inputs were much lower than these requirements. The accumulation of 11 cmolc kg−1 exchangeable Al (268 kmolc ha−1) can account for 1 unit drop of soil pH in 68 years. The discrepancy might be related to accumulation of soil organic matter. We found quantitatively that N deposition and plant uptake can account for almost half of soil acidification.
著者氏名	○Kazumichi Fujii1 ・ Zhou Zhang2 ・ Fang, Yungting3
著者所属	1Forestry and Forest Products Research Institute ・ 2Research Institute of Tropical Forestry ・ 3Institute of Applied Ecology
キーワード	Soil acidification, Nitrogen deposition, Nitrification
Key word	Soil acidification, Nitrogen deposition, Nitrification