Video Experimental Relacionado
Updated: Jul 11, 2026
04:54
Assessing Mineral Availability in Fish Feeds using Complementary Methods Demonstrated with the Example of Zinc in Atlantic Salmon
Published on: October 29, 2021
Deposición de zinc en lagos ácidos: el papel de la difusión
Science (New York, N.Y.)
|June 28, 1985
Resumen
El zinc disuelto en las aguas porosas del lago ácido forma sulfuros insolubles, lo que lleva a la deposición en sedimentos. Los picos de zinc subterráneos pueden indicar procesos diagenéticos, no sólo la acidificación del lago.
Área de la Ciencia:
- Química del medio ambiente Química del medio ambiente
- La geoquímica es la geoquímica.
- Limología Limología.
Sus antecedentes:
- Los lagos ácidos exhiben gradientes pronunciados de zinc disuelto entre el agua y las aguas porosas anóxicas.
- Las bajas concentraciones de zinc en aguas porosas anóxicas sugieren la formación de minerales insolubles de sulfuro de zinc.
Objetivo del estudio:
- Para investigar el destino del zinc disuelto en los sedimentos de los lagos ácidos.
- Para determinar la contribución de los flujos difusos hacia abajo a la deposición de zinc.
- Para explorar las causas de los máximos de zinc subterráneo en los sedimentos de los lagos.
Principales métodos:
- Análisis de las concentraciones de zinc disuelto en aguas superpuestas y aguas de poros anóxicos.
- Cuantificación de flujos difusos hacia abajo de zinc disuelto.
- Observación de la distribución total de zinc dentro de los núcleos del sedimento.
Principales resultados:
- Los flujos difusos descendentes de zinc disuelto contribuyen entre el 50 y el 75% a la deposición reciente de zinc.
- Se observan máximos subsuperficiales pronunciados en el zinc total a 2-3 cm por debajo de la interfaz sedimento-agua.
- Estos picos de zinc subterráneo pueden ser el resultado de una actividad diagenética no relacionada con la reciente acidificación de los lagos.
Conclusiones:
- La precipitación de sulfuro de zinc es un proceso clave que controla las concentraciones de zinc en aguas de poros anóxicos.
- Los procesos diagenéticos, independientemente de la acidificación reciente, pueden crear picos de zinc subterráneos en los sedimentos del lago.
- Comprender la diagenesis del zinc es crucial para interpretar los registros de sedimentos en lagos ácidos.
Videos de Conceptos Relacionados
01:19Acid 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...
01:24Microbes 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...
01:27Microbial Leaching
Microbial leaching, also known as bioleaching, is an environmentally favorable method for extracting metals from low-grade ores using specific microorganisms. This biotechnological approach is particularly valuable for mining operations targeting copper, gold, and uranium, where traditional extraction methods may be economically or environmentally impractical.Copper Leaching and Microbial CatalysisIn copper bioleaching, crushed ore is arranged into heaps and irrigated with a dilute sulfuric...
03:45Formation of Complex Ions
A type of Lewis acid-base chemistry involves the formation of a complex ion (or a coordination complex) comprising a central atom, typically a transition metal cation, surrounded by ions or molecules called ligands. These ligands can be neutral molecules like H2O or NH3, or ions such as CN− or OH−. Often, the ligands act as Lewis bases, donating a pair of electrons to the central atom. These types of Lewis acid-base reactions are examples of a broad subdiscipline called coordination...
01:08Electrodeposition
Electrodeposition is a technique used to separate an analyte from interferents by electrochemical processes. Here, the analyte is a metal ion that can be deposited on an electrode immersed in the sample solution. The electrochemical setup consists of an anode and a cathode. When an electric current is applied to the setup, oxidation occurs at the anode. At the cathode, which consists of a large metal surface, metal ions undergo reduction and deposit onto the surface.
Electrodeposition can...
Electrodeposition can...
03:02Standard Electrode Potentials
On comparing the reactivity of silver and lead, it is observed that the two ionic species, Ag+ (aq) and Pb2+ (aq), show a difference in their redox reactivity towards copper: the silver ion undergoes spontaneous reduction, while the lead ion does not. This relative redox activity can be easily quantified in electrochemical cells by a property called cell potential. This property is commonly known as cell voltage in electrochemistry, and it is a measure of the energy which accompanies the charge...