College of Resources and Environment, Southwest University, Chongqing, 400715, China.
Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences & Ministry of Water Conservancy, Chengdu, 610041, China.
Environ Pollut. 2020 May;260:114082. doi: 10.1016/j.envpol.2020.114082. Epub 2020 Jan 29.
Ice and sediment cores, peat bogs and tree rings are useful proxy records for reconstructing historical air pollution events. However, these indirect measurements are subject to interferences caused by environmental perturbations including global climate change. Therefore, using multiple proxy records has advantages in constraining the analytical findings. In this study, we utilized the chronological record of atmospheric deposition preserved in vegetation succession ecosystems in the deglaciated region for reconstructing historical pollution events. The rate of Cd accumulation in the forest chronosequence zone was investigated in a deglaciated area of the Tibetan Plateau. The results obtained through this novel approach are consistent with the variations of Cd concentration recorded in tree-ring, showing a 4-7 times increase of atmospheric Cd deposition from the 1890s to the early 1970s followed by a decrease from the mid-1970s-2000s. The Cd pollution record indicates that elevated atmospheric Cd release occurred in regions of Southwest China and South Asia due to the rapid industrial development until 1970 followed by coordinated efforts in controlling air emissions after mid-1970s.
冰芯、沉积芯、泥炭沼泽和树木年轮是重建历史空气污染事件的有用替代记录。然而，这些间接测量受到环境干扰的影响，包括全球气候变化。因此，使用多个替代记录在约束分析结果方面具有优势。在这项研究中，我们利用在冰川消退地区植被演替生态系统中保存的大气沉积的年代记录来重建历史污染事件。在青藏高原冰川消退地区，研究了森林序列区中 Cd 的积累速率。通过这种新方法获得的结果与树木年轮记录的 Cd 浓度变化一致，显示从 19 世纪 90 年代到 20 世纪 70 年代初，大气 Cd 沉积增加了 4-7 倍，随后从 20 世纪 70 年代中期到 2000 年代减少。Cd 污染记录表明，由于 20 世纪 70 年代前的快速工业发展，中国西南和南亚地区大气 Cd 释放增加，随后在 20 世纪 70 年代中期后协调控制空气排放。
