Ning Wenjing, Hu Yuwei, Feng Siyao, Cao Min, Luo Jie
School of Environment, Nanjing University, Nanjing, China.
College of Resources and Environment, Yangtze University, Wuhan, China.
Sci Total Environ. 2023 Dec 20;905:167197. doi: 10.1016/j.scitotenv.2023.167197. Epub 2023 Sep 22.
The Qinghai-Tibet Plateau is distinguished by its diverse ecosystems and biodiversity, which are highly dependent on their soil. In this study, a comprehensive analysis was conducted to assess the ecological risks in Maqin County, located on the Qinghai-Tibet Plateau, along with the local background values of soil elements, level of element enrichment, and source appointment of soil elements. The findings show that the background soil element levels in Maqin County were greater than the average soil content values in China. The soils in the study area exhibited pollution levels ranging from weak to moderate. The positive matrix factorization (PMF) model was employed to successfully categorized soil elements into four sources: F1 (natural sources), F2 (grazing sources), F3 (volcanic and rock fracture sources), and F4 (intrusive and deep rock source). Based on the characteristics of the ecological communities and the network environmental analysis model, ecological risks were directly introduced through vegetation and soil microorganisms, with subsequent transmission to other components of the ecosystem through the food chain. The integrated risks associated with vegetation, herbivores, soil microorganisms, and carnivores were 0.0106, 0.00193, 0.0282, and 0.00132, respectively. Notably, soil microorganisms were found to be the primary contributors to the total ecological risk in the study area. Furthermore, network environmental analysis and human health risk models revealed that F1, F2, F3, and F4 accounted for 16.85 %, 8.90 %, 21.76 %, and 52.49 % of the input risk of vegetation and soil microorganisms, respectively. Particularly, F4 emerged as the largest contributor to human health risks. This study provides valuable information for the preservation of the ecological environment in pastoral areas, contributing to the global promotion of sustainable ecological practices.
青藏高原以其多样的生态系统和生物多样性而著称，这些生态系统和生物多样性高度依赖于其土壤。在本研究中，对位于青藏高原的玛沁县进行了全面分析，评估了其生态风险以及土壤元素的当地背景值、元素富集程度和土壤元素的来源归属。研究结果表明，玛沁县土壤元素的背景水平高于中国土壤平均含量值。研究区域的土壤污染程度从轻度到中度不等。采用正定矩阵因子分解（PMF）模型成功地将土壤元素分为四个来源：F1（自然源）、F2（放牧源）、F3（火山和岩石断裂源）和F4（侵入和深部岩石源）。基于生态群落的特征和网络环境分析模型，通过植被和土壤微生物直接引入生态风险，随后通过食物链传递到生态系统的其他组成部分。与植被、食草动物、土壤微生物和食肉动物相关的综合风险分别为0.0106、0.00193、0.0282和0.00132。值得注意的是，土壤微生物被发现是研究区域总生态风险的主要贡献者。此外，网络环境分析和人类健康风险模型显示，F1、F2、F3和F4分别占植被和土壤微生物输入风险的16.85%、8.90%、21.76%和52.49%。特别是，F4是人类健康风险的最大贡献者。本研究为牧区生态环境保护提供了有价值的信息，有助于在全球范围内推广可持续生态实践。
