Video Experimental Relacionado
Updated: Aug 1, 2026
09:45
Laboratory Simulation of an Iron(II)-rich Precambrian Marine Upwelling System to Explore the Growth of Photosynthetic Bacteria
Published on: July 24, 2016
Morfología fluvial alterada en Sudáfrica relacionada con la extinción del Permiano-Triásico
Ward1, Montgomery, Smith
1Department of Geological Sciences, University of Washington, Seattle, WA 98195, USA. South African Museum, Cape Town, South Africa.
Science (New York, N.Y.)
|September 8, 2000
Resumen
El límite Pérmico-Triásico vio ríos en Sudáfrica.
Área de la Ciencia:
- Geología sedimentaria y paleontología.
- Ciencias de la Tierra y cambio ambiental.
Sus antecedentes:
- La transición Pérmico-Triásico en la cuenca del Karoo, Sudáfrica, exhibió un cambio significativo en los sistemas fluviales.
- Este período geológico es conocido por un importante evento de extinción que afectó a los ecosistemas terrestres.
Objetivo del estudio:
- Para investigar la causa de los rápidos cambios en el sistema fluvial durante la transición Pérmico-Triásico.
- Para vincular los cambios geomórficos de los ríos con la extinción de la vegetación terrestre.
Principales métodos:
- Análisis de las fajas sedimentarias en la cuenca del Karoo.
- Correlación con las secciones globales del límite Pérmico-Triásico.
Principales resultados:
- Se observó una rápida transición de los sistemas fluviales serpenteantes a los sistemas fluviales trenzados en la cuenca del Karoo.
- Este cambio en la morfología del río se alinea con los impactos geomórficos de la pérdida generalizada de vegetación.
- La evidencia global sugiere un evento catastrófico de extinción de plantas terrestres.
Conclusiones:
- La desaparición de las plantas con raíces alteró significativamente la geomorfología de los ríos.
- El aumento del rendimiento de los sedimentos y la excursión global de isótopos de carbono están vinculados a este colapso de la vegetación.
Más Videos Relacionados
06:55Kinematic History of a Salient-recess Junction Explored through a Combined Approach of Field Data and Analog Sandbox Modeling
Published on: August 5, 2016
10:14Reconstructing Terrestrial Paleoclimate and Paleoecology with Fossil Leaves Using Digital Leaf Physiognomy and Leaf Mass Per Area
Published on: October 25, 2024
Videos de Conceptos Relacionados
01:50Threats to Biodiversity
There have been five major extinction events throughout geological history, resulting in the elimination of biodiversity, followed by a rebound of species that adapted to the new conditions. In the current geological epoch, the Holocene, there is a sixth extinction event in progress. This mass extinction has been attributed to human activities and is thus provisionally called the Anthropocene. In 2019 the human population reached 7.7 billion people and is projected to comprise 10 billion by...
01:07Speciation Rates
Speciation can proceed at markedly different rates, and evolutionary biologists commonly describe these differences through the models of gradualism and punctuated equilibrium. Both patterns explain how new species arise, but they differ in the tempo and continuity of evolutionary change. In both cases, evolutionary change arises from heritable variation within populations, with natural selection often shaping traits that improve survival and reproduction under specific environmental conditions.
02:07Conservation of Declining Populations
Conservation of declining population focuses on ways of detecting, diagnosing, and halting a population decline. The approach uses methods to prevent populations from going extinct.
02:31Habitat Fragmentation
Habitat fragmentation describes the division of a more extensive, continuous habitat into smaller, discontinuous areas. Human activities such as land conversion, as well as slower geological processes leading to changes in the physical environment, are the two leading causes of habitat fragmentation. The fragmentation process typically follows the same steps: perforation, dissection, fragmentation, shrinkage, and attrition.
02:39Gene Flow
Gene flow is the transfer of genes among populations, resulting from either the dispersal of gametes or from the migration of individuals.
02:56The Fossil Record
The fossil record documents only a small fraction of all organisms that have ever inhabited Earth. Fossilization is a rare process, and most organisms never become fossils. Moreover, the fossil record only exhibits fossils that have been discovered. Nevertheless, sedimentary rock fossils of long-lived, abundant, hard-bodied organisms dominate the fossil record. These fossils offer valuable information, such as an organism's physical form, behavior, and age. Studying the fossil record helps...