海洋酸化对海洋植物浮游生物的铁供应的影响
Dalin Shi1, Yan Xu, Brian M Hopkinson
1Department of Geosciences, Princeton University, Princeton, NJ 08544, USA. dshi@princeton.edu
概括
由于二氧化碳 (CO2) 的海洋酸化减少了铁 (Fe) 对海洋生物的生物可用性. 这项研究表明植物浮游生物的铁吸收减少,可能会增加海洋种群的铁压力.
科学领域:
- 海洋化学 海洋化学
- 海洋学 海洋学 海洋学
- 海洋生物学 海洋生物学
背景情况:
- 由人为二氧化碳 (CO2) 吸收驱动的海洋酸化改变了海水的化学成分.
- 铁 (Fe) 是许多海洋地区植物浮游生物的关键限制营养素.
- 海洋化学的变化可能会影响铁等必需营养素的生物可用性和吸收.
研究的目的:
- 研究海洋酸化对溶解铁 (Fe) 的生物可用性的影响.
- 为了确定化过程中Fe化学的变化如何影响关键海洋植物浮游生物的Fe吸收.
- 评估海洋酸化对浮游植物铁营养的潜在后果.
主要方法:
- 在酸性条件下使用各种铁 (Fe) 化合物进行实验.
- 测量了 diatom 和 coccolithophores 的 Fe 吸收率.
- 用模型藻和大西洋表面水进行了实验室实验,以模拟变化的pH值.
- 在高二氧化碳条件下评估了模型植物浮游生物的Fe需求.
主要成果:
- 海洋酸化显著降低了溶解的铁 (Fe) 的生物可用性.
- 藻和藻类的Fe吸收率下降,正如改变的Fe化学与降低pH值所预测的那样.
- 一个模型藻在与大西洋表面水的pH值下降的实验中表现出更慢的Fe吸收.
- 模型植物浮游生物的铁 (Fe) 需求没有随着二氧化碳水平的增加而改变.
结论:
- 海洋酸化可能会降低表面水中的铁 (Fe) 生物可用性.
- 某些海洋地区的浮游生物种群可能会由于持续的酸化而增加铁 (Fe) 应激.
- 了解这些化学变化对于预测未来海洋生态系统反应至关重要.
更多相关视频
10:43Unraveling the Unseen Players in the Ocean - A Field Guide to Water Chemistry and Marine Microbiology
Published on: November 5, 2014
06:52Experimental Column Setup for Studying Anaerobic Biogeochemical Interactions Between Iron (Oxy)Hydroxides, Trace Elements, and Bacteria
Published on: December 19, 2017
相关概念视频
Microbes and Other Elemental Cycles
Microbial activity plays a pivotal role in the biogeochemical cycling of iron and manganese, especially at the redox gradients characteristic of stratified aquatic environments. These cycles are driven by microbial transformations between oxidized and reduced forms of the metals, allowing organisms to exploit them for metabolic energy and structural purposes.Iron Cycling Across Redox GradientsIn neutral, oxygen-rich surface waters, iron is predominantly found in its oxidized, insoluble ferric...
Marine Microbial Ecology
Marine microbial ecosystems are shaped by distinct physicochemical limits, including high salinity, low nutrient availability, and fluctuating oxygen levels. These conditions favor smaller microbial cell sizes, which maximize their surface-to-volume ratio for efficient nutrient uptake.Microbial activity and community composition are closely linked to biogeochemical cycles, particularly in dynamic environments like estuaries, where halotolerant microbes thrive in response to variable salinity...
Acid Mine Drainage
Mining activities that disturb sulfide-rich rocks, particularly those containing pyrite (FeS₂), initiate a cascade of geochemical and microbiological processes with serious environmental implications. When exposed to air and water, pyrite undergoes oxidation, releasing sulfate, ultimately forming sulfuric acid and mobilizing heavy metals into surrounding water systems. This phenomenon, known as acid mine drainage (AMD), results in low pH waters laden with toxic elements that threaten aquatic...
Primary Production
The total amount of energy acquired by primary producers in an ecosystem is called gross primary production (GPP). However, of this energy, producers use some for metabolic processes, and some is lost as heat, decreasing the amount of energy available to the next trophic level. The remaining usable amount of energy is called the net primary productivity (NPP). In terrestrial ecosystems, NPP is driven by climate, while light penetration and nutrient availability drive NPP in aquatic ecosystems.
Factors Affecting Solubility
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:
Metabolism of Chemolithotrophs
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. However, because inorganic electron donors...
