Assessment of the maximum allowed acid deposition load at current stage in China
Bingwen Li
,
Zhangwei Wang
,
Xiaoshan Zhang
DOI:10.1016/j.jes.2016.05.047
Received December 20, 2015,Revised January 13, 2016, Accepted June 01, 2016, Available online October 25, 2016
Volume 29,2017,Pages 140-144
Soil acidification caused by acid deposition has been significant in some forests in southern China. We present an approach for assessing the current stage maximum allowed load (SML) of acid deposition for terrestrial system in the country. The main idea was that soil base cation exchange as a finite buffer to acidity was included in the soil acidity mass balance calculation at current acidification stage. We calculated the SML for five forests in southern China. The usual critical loads for the same forests were also calculated by the steady state mass balance model for comparison. The results showed that the SML is a more tolerant limit than the critical load for the forests with soils not acidified seriously at current stage. However, the SML become a more stringent limit to acid deposition when the forest soils have acidified seriously to very low base cation saturation. In this case the SML assessment is beneficial for the soils recovering from a serious acidified state. Based on a national scale database, the SML mapping for non-agricultural soil system in China was carried out.
