Key Laboratory of Cryospheric Science and Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China.
Key Laboratory of Cryospheric Science and Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China; Lanzhou University of Arts and Science, Lanzhou 730000, China.
Sci Total Environ. 2024 Dec 1;954:176652. doi: 10.1016/j.scitotenv.2024.176652. Epub 2024 Oct 1.
The Tibetan Plateau is one of the highest and most pristine plateaus in the world, and its ecological environment has a significant impact on global climate and the distribution of water resources. Mercury (Hg), as a toxic metal pollutant, can have a severe impact on the health of living organisms and the ecosystem due to its presence in the environment. This study collected 336 soil samples from 28 sites across four typical surface vegetation landscapes (meadow, grassland, desert, and forest) on the Tibetan Plateau to measure soil THg (Total Hg) concentrations. The research aimed to explore the factors influencing soil THg levels, analyze pollution and environmental risks of THg in the surface soil, and evaluate the associated health risks to the local population. The results indicate that the mean soil THg concentration (31.84 ± 32.58 ng·g) of this study is compared to the background value of THg in Tibetan Plateau soils (37.0 ng·g), but there are significant differences in THg concentration among soils with different surface vegetation landscapes. The mean THg concentration in soils of forest vegetation types (74.42 ± 41.19 ng·g) is approximately twice the background value of Tibetan Plateau soils. In the forested regions of the southeastern, eastern, and southern Tibetan Plateau, soil concentrations of total mercury are relatively high, whereas in the desert areas of the northern, northwestern, and northeastern Tibetan Plateau, the concentrations are lower. Organic matter (soil organic carbon) being an important factor influencing the soil THg. Based on existing surface soil THg data from this and previous research in Tibetan Plateau (n = 477), 34.2 % of the samples show Hg pollution and potential ecological risks. However, the health risks of soil Hg to both adults and children are not significant.
青藏高原是世界上海拔最高、自然环境最为原始的高原之一，其生态环境对全球气候和水资源分布有着重要影响。汞（Hg）作为一种有毒金属污染物，由于其在环境中的存在，会对生物的健康和生态系统造成严重影响。本研究在青藏高原四个典型的地表植被景观（草地、草原、荒漠和森林）的 28 个地点采集了 336 个土壤样本，以测量土壤总汞（THg）浓度。本研究旨在探讨影响土壤 THg 水平的因素，分析地表土壤中 THg 的污染和环境风险，并评估当地居民面临的相关健康风险。结果表明，本研究的土壤 THg 浓度平均值（31.84±32.58ng·g）与青藏高原土壤中 THg 的背景值（37.0ng·g）相比有所降低，但不同地表植被景观土壤中的 THg 浓度存在显著差异。森林植被类型土壤中的 THg 浓度平均值（74.42±41.19ng·g）约为青藏高原土壤背景值的两倍。在青藏高原东南部、东部和南部的森林地区，土壤总汞浓度相对较高，而在北部、西北部和东北部的荒漠地区，浓度则较低。有机质（土壤有机碳）是影响土壤 THg 的重要因素。基于本研究和青藏高原以往研究中现有的地表土壤 THg 数据（n=477），34.2%的样本显示 Hg 污染和潜在的生态风险。然而，土壤 Hg 对成人和儿童的健康风险并不显著。
