围垦对辽东湾北部滨海湿地土壤重金属含量的影响及生态风险评价

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 围垦对辽东湾北部滨海湿地土壤重金属含量的影响及生态风险评价 DOI: 10.5846/stxb201908061654 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 辽宁省自然科学基金项目（2020-BS-183）；辽宁省教育厅人文社科研究项目（WQ2019020）；辽宁省社会科学规划基金项（L19CJY005）；辽宁省省社科联 2021年度辽宁省经济社会发展研究课题（2021lslybkt-055） Effect of reclamation on soil heavy metal content of coastal wetland and ecological risk assessment in Northern Liaodong Bay, China Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:围垦历史与围垦方式被认为是人类对滨海湿地生态系统干扰的主要因素。选取辽东湾北部区作为研究区，采集129个表层土壤样品（0-20 cm），测定土壤理化性质（盐分、pH、土壤颗粒组成、土壤有机碳、硝态氮、速效磷）和重金属元素（Fe、Mn、Cu、Cr、Cd、Ni、Zn、Pb）含量；运用多元统计和反距离权重插值方法揭示研究区土壤重金属元素的来源与空间分布特征，最后利用Hakanson潜在生态风险指数法对重金属的潜在生态风险进行评价。结果表明：①6种重金属表现为彼此的显著正相关（P<0.01）。除Pb外，Cd、Cr、Cu、Ni和Zn的浓度与土壤有机碳、黏粒、粉粒含量呈极显著正相关（P<0.01），而与砂含量呈极显著负相关（P<0.01）。②化工、造纸、石油开采及加工等工业活动可能引起Cr、Cu、Ni和Zn的富集，持续的农业施肥和农药使用可能会增加土壤中Cd、Pb的含量。③围垦初期（1990s），土壤侵蚀和淋洗脱盐对土壤重金属分布具有显著影响。随着开垦年限的延长（1960s），持续的农业施肥、工业活动（如造纸、石油开采）和城市扩建，都大大增加了土壤重金属含量的累积。④不同的围垦方式影响下，除Fe标准化的Cd和Pb在水产养殖区有较高的浓度外，Fe标准化的Cr、Ni、Cu和Zn的浓度均在自然区域（滩地和芦苇）高于人类活动区域（水产养殖、耕地、建设用地）。⑤综合潜在生态风险指数平均值为325.69，表现为极强的生态风险程度，其中Cd表现为极高生态风险的采样点比例为46.51%，是造成区域重金属污染的主要贡献元素，特别是在水产养殖和农业地区。 Abstract:The history and methods of reclamation are considered as the main factors that drive human to disturb the coastal wetland ecosystems. In this study, a total of 129 samples were collected from the topsoil (0-20 cm) in Northern Liaodong Bay, and were determined for their physical and chemical properties (including salinity, pH, soil particle composition, SOC, NO3-N, and AP) and heavy metal levels (including Fe, Mn, Cu, Cr, Cd, Ni, Zn, and Pb). The heavy metals in soils were studied for sources and spatial distribution by using multivariate analysis and Inverse Distance Weight (IDW) interpolation method, and were evaluated for the potential ecological risk by using Hakanson's method. The results showed that: ①The levels of six heavy metals were significantly positively correlated (P<0.01) with each another. The Cd, Cr, Cu, Ni and Zn (excluding Pb) concentrations were significantly positively correlated (P<0.01) with the SOC, clay, and silt content, but were significantly negatively correlated (P<0.01) with the sand content. ②The levels of Cr, Cu, Ni and Zn in soils might be influenced by industrial activities (chemical industry, paper, oil exploitation and processing). Continuous use of fertilizers and pesticides might increase the levels of Cd and Pb in soils. ③In the early stage of reclamation (1990s), soil erosion, leaching and desalination had significant effects on the distribution of heavy metals in soils. Until the 1960s, continuous agricultural fertilization, industrial activities (such as paper making, and petroleum exploitation), and urban expansion had greatly increased the levels of heavy metals in soils. ④Under the influence of different reclamation methods, except that the levels of Fe standardized Cd and Pb were higher in the aquaculture areas, while the levels of Cr, Ni, Cu and Zn were higher in natural areas (marsh and reeds) than in human areas (aquaculture areas, cultivated land and construction land). ⑤The average value of the comprehensive potential ecological risk index was 325.69, showing a high level of risk. The Cd accounted for 46.51% as the highest ecological risk element in samples, which was the major contributor to heavy metal pollution, especially in aquaculture and agricultural areas. 参考文献 相似文献 引证文献