碳酸盐岩作为天然缓冲剂:探索它们对硫化物沉积中的重金属对环境的影响
Kun Lin1, Tao Yu2, Wenbing Ji3
1School of Earth Sciences and Resources, China University of Geosciences, Beijing, 100083, China.
Environmental pollution (Barking, Essex : 1987)
|September 6, 2023
概括
碳酸盐岩石缓冲多金属硫化物开采中的重金属,减少生态风险. 这项研究表明,碳酸盐缓冲降低了金属在水和土壤中的流动性,有助于安全的农田管理.
科学领域:
- 环境科学 环境科学
- 地质化学 地质化学
- 农业科学 农业科学
背景情况:
- 多金属硫化物沉积物与碳酸盐岩石有关,碳酸盐岩石自然缓冲重金属.
- 忽视这种缓冲效应会导致不准确的生态风险评估和资源管理不善.
- 了解土壤-大米系统中的金属物种化和迁移对于环境保护至关重要.
研究的目的:
- 调查水和土壤水系统中的 (Cd), (Zn) 和 (Pb) 的分布和物种化.
- 揭示天然碳酸盐岩石缓冲对重金属迁移和转化的影响.
- 为采矿区的生态风险评估和农田管理提供基础.
主要方法:
- 在多金属硫化物沉积区对水,土壤和大米进行现场采样和分析.
- 确定重金属度 (Cd,Zn,Pb) 和在不同环境组件中的物种化.
- 评估土壤特性 (pH,CaO,Fe2O3,Mn) 以及它们对金属生物可用性和吸收的影响.
主要成果:
- 碳酸盐缓冲将水的pH值从2.80提高到7.64,使溶解的Cd和Zn度在下游显著下降.
- 由于pH值增加,重金属 (Cd,Zn,Pb) 倾向于在沉积物中沉和丰富.
- 土壤中Cd含量在采矿区很高,但下游下降,Cd主要与Fe-Mn和碳酸盐分量结合,降低了生物可用性.
结论:
- 碳酸盐岩石的自然缓冲在减少重金属的流动性和生物可用性方面发挥着至关重要的作用.
- 对于食品安全和资源利用,建议制定考虑土壤和大米Cd含量的农田管理计划.
- 这些发现支持碳酸盐硫化物矿区的科学风险评估和环境管理策略.
相关概念视频
Factors Affecting Solubility
33.5K
Compared with pure water, the solubility of an ionic compound is less in aqueous solutions containing a common ion (one also produced by dissolution of the ionic compound). This is an example of a phenomenon known as the common ion effect, which is a consequence of the law of mass action that may be explained using Le Chȃtelier’s principle. Consider the dissolution of silver iodide:
33.5K
Extraction: Advanced Methods
482
Metal ions can be separated from one another by complexation with organic ligands–the chelating agent– to form uncharged chelates. Here, the chelating agent must contain hydrophobic groups and behave as a weak acid, losing a proton to bind with the metal. Since most organic ligands used in this process are insoluble or undergo oxidation in the aqueous phase, the chelating agent is initially added to the organic phase and extracted into the aqueous phase. The metal-ligand complex is...
482
Bicarbonate-Carbonic Acid Buffer
1.6K
The carbonic acid-bicarbonate buffer system is critical for maintaining the body's pH balance. It operates on the equilibrium:
1.6K
Metabolism of Chemolithotrophs
40
Chemolithotrophs are microorganisms that obtain energy by oxidizing inorganic molecules such as hydrogen gas (H₂), ammonia (NH₃), reduced sulfur compounds (H₂S, S²⁻), and ferrous iron (Fe²⁺). Unlike heterotrophic organisms that rely on organic carbon, chemolithotrophs transfer electrons from these inorganic donors to the electron transport chain (ETC), generating a proton motive force (PMF) that drives ATP synthesis through oxidative phosphorylation.
40
The Sulfur Cycle
44.9K
Sulfur, an important element in the chemical makeup of proteins, is recycled through the atmosphere and aquatic and terrestrial environments. Found in the atmosphere as sulfur dioxide (SO2), sulfur is released by decaying organisms, weathered rocks, geothermal vents, volcanos, and burning fossil fuels. It is deposited into the ecosystem, cycled through the biotic community, and either released back into the atmosphere as gas or deposited in marine sediment for long-term storage and eventual...
44.9K
Bioremediation
18.9K
Bioremediation is the use of prokaryotes, fungi, or plants to remove pollutants from the environment. This process has been used to remove harmful toxins in groundwater as a byproduct of agricultural run-off and also to clean up oil spills.
18.9K


