Video Experimental Relacionado
Updated: Jul 12, 2026
09:31
Preparation of Authigenic Pyrite from Methane-bearing Sediments for In Situ Sulfur Isotope Analysis Using SIMS
Published on: August 31, 2017
El azufre biogénico y la acidez de las lluvias en áreas remotas de Canadá
Science (New York, N.Y.)
|September 4, 1987
Resumen
Las fuentes biogénicas de azufre contribuyen hasta en un 30% al azufre atmosférico en el remoto Canadá. Esto indica una reemisión biológica significativa de azufre antropogénico, una preocupación por la acidificación ambiental en curso.
Área de la Ciencia:
- Química del medio ambiente Química del medio ambiente
- La geoquímica de los isótopos es la geoquímica de los isótopos.
- Ciencias de la atmósfera Ciencias atmosféricas.
Sus antecedentes:
- La firma isotópica del azufre permite rastrear el flujo ambiental de fuentes naturales y antropogénicas.
- La acidificación sigue siendo una preocupación ambiental significativa en muchas regiones.
Objetivo del estudio:
- Cuantificar la contribución de las fuentes biogénicas de azufre a la carga atmosférica de azufre en el remoto Canadá.
- Investigar el potencial para la reemisión biológica de azufre antropogénico.
Principales métodos:
- Se recogieron muestras semanales de precipitación masiva durante un período de 4 años.
- Concentración de azufre medida y composición isotópica.
- Evaluación de la producción y liberación de dimetilsulfuro de humedales boreales.
Principales resultados:
- Las fuentes biogénicas de azufre pueden representar hasta el 30% de la carga de azufre acidificante en atmósferas canadienses remotas.
- Los datos sugieren que se está produciendo una reemisión biológica significativa de azufre antropogénico.
Conclusiones:
- El ciclo biogénico del azufre juega un papel sustancial en la dinámica atmosférica del azufre en áreas remotas.
- La reemisión biológica de azufre antropogénico es un factor crítico en la acidificación ambiental a largo plazo.
Videos de Conceptos Relacionados
01:29Microbes and the Sulfur Cycle
Sulfur is a vital element in Earth's biogeochemical systems. It transitions through various inorganic states, including sulfate (SO₄²⁻), elemental sulfur (S⁰), and sulfide (S²⁻). Abiotic and biological mechanisms across oxic and anoxic environments intricately mediate these transformations. Sulfate, the most oxidized form of sulfur, is predominantly stored in rocks, marine sediments, and oceanic waters, acting as a long-term reservoir in the global sulfur cycle.In oxic environments,...
01:22The Sulfur Cycle
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...
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...
01:20Sulfur Assimilation
Sulfur is an essential element in biological systems, contributing to synthesizing key biomolecules, including amino acids such as cysteine and methionine, and cofactors such as coenzyme A and biotin. Microorganisms primarily assimilate sulfur as sulfate (SO₄²⁻) from the environment, which must undergo a series of biochemical transformations before it can be incorporated into cellular components. As sulfate is highly oxidized, it must undergo assimilatory sulfate reduction to become...
01:27Microbes and Climate Change
Microorganisms are pivotal agents in Earth's biogeochemical cycles, significantly influencing climate dynamics through their metabolic activities. These microbes modulate the levels of key greenhouse gases by both contributing to and helping mitigate climate change.Microbial Contributions to Greenhouse Gas EmissionsRising global temperatures accelerate microbial metabolism, which, in turn, speeds up the decomposition of organic matter. This process releases carbon dioxide (CO₂) through...
01:24Freshwater Microbial Ecology
Freshwater systems such as streams, rivers, and lakes exhibit distinct physical and biological characteristics that influence their microbial communities. These environments are broadly categorized into lotic systems—those with flowing waters like streams and most rivers—and lentic systems, which include still or slow-moving waters such as lakes, ponds, and marshes.In lentic systems, phytoplankton drive primary production, generating autochthonous organic carbon. In contrast, lotic systems...