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There is an exceptionally rich aquatic fauna in the epikarst, the skin of karst. High species richness in the epikarst, coupled
with its special vulnerability as the first point of entry of nearly all toxic spills, makes its protection especially important.
The epikarst fauna may also be an useful tool in tracing the potential route of pollutants. Copepods in epikarst have extremely
local distributions, and their body size is such that they are largely at the mercy of directional flows. In a series of caves
in southwest Slovenia and West Virginia, a significant fraction of the copepod species occur in less than 100 m of linear
extent. This suggests a pattern of highly restricted lateral flow under normal conditions and the distribution of copepods
could potentially be used to trace water movement. Under high flow conditions as would often be the case with toxic spill,
mounding of water may increase the lateral radius of flow. Nevertheless, copepods may be useful tracers. 相似文献
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A framework for karst ecohydrology 总被引：7，自引：0，他引：7
Ecohydrology can be defined as the science of integrating hydrological and biological processes over varied spatial and temporal
scales. There exists in karst a strong and direct interaction between the circulation and storage of groundwater and surface
water. These fluxes in turn affect the spatial distribution of organisms in these habitats. Because of the fact that the appearance,
storage and circulation of water in karstified areas is significantly different from other more homogenous and isotropic terrains,
karst ecohydrology should develop original methods and approaches. At the same time, traditional approaches are also very
useful. Large karst underground geomorphological patterns occur in many sizes and varieties, ranging from a few meters long
or deep to very large, the deepest being deeper than 1 km and longer than hundreds of kilometres. In this article, special
attention is paid to ecohydrological functions of karst underground features (caves, pits, conduits, etc.), which play a crucial
dual role in (1) hydrology and hydrogeology of water circulation and storage and (2) ecology of many rare and endangered species.
Differences in morphology, hydrology, hydrogeology and climate have resulted in a range of different environments, which provide
the opportunity for the coexistence of different species. The role of the epikarst and vadose zones, as well as caves in ecohydrological
processes, is discussed. The importance of the flood factor in karst ecology is analysed. The aim of this article is to move
forward the discussion among different disciplines to promote and develop a conceptual framework for karst ecohydrology. 相似文献
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R. R. Colucci E. Forte C. Boccali M. Dossi L. Lanza M. Pipan M. Guglielmin 《Surveys in Geophysics》2015,36(2):231-252
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The distribution of 27 copepod species was determined in 35 drips in four Slovenian caves (Dimnice, Postojna Planina Cave
System, Škocjanske Jame, Županova Jama), and of ten species from 13 drips in one US cave (Organ Cave, West Virginia). The
dripping water comes from epikarst, the skin of karst. A significant fraction of the copepod species found (nine species in
Slovenia and three in West Virginia) occurred over a maximum linear extent of 100 m. These and other localized distributions
probably resulted from colonization of epikarst by an ancestral surface population in a single location, with subsequent lateral
spread in the direction of epikarst flow. This suggests that the distribution of copepods could potentially be used to trace
major flow paths in epikarst without the need for the injection of dyes or other tracers.
Résumé La distribution de 27 espèces de copépodes a été déterminée dans 35 zones de percolation de quatre grottes slovènes (Dimnice, système de grottes Postojna Planina, Škocjanske Jame, Županova Jama) et grace à dix espèces de 13 zones de percolation d’une grotte des Etats-Unis (Grotte Organ, Ouest de la Virginie). L’eau de percolation provient de l’épikarst, la partie supérieure du karst. Une fraction importante des espèces de copépodes trouvées (9 espèces en Slovénie et 3 dans l’Ouest de la Virginie) s’étendait sur une longueur maximum de 100 m. Ces dernières ainsi que d’autres distributions localisées étaient probablement issues de la colonisation par une population ancienne de surface, de zones localisées de l’épikarst, puis par une dispersion latérale dans la direction de l’écoulement dans l’épikarst. Ceci suggère que la distribution des copépodes pourrait potentiellement être utilisée pour identifier les principales trajectoires d’écoulement dans l’épikarst, sans utiliser l’injection de colorants ou d’autres traceurs.
Resumen Se determina la distribución de 27 especies de copépodo en 35 gotas de cuatro cavernas de Eslovenia (Dimnice, Sistema de Caverna Planina Postojna, Jame Škocjanske, y Jama Županova), y de diez especies en 13 gotas de una caverna de Estados Unidos (Caverna órgano, Virginia Occidental). El agua que gotea se deriva del epikarst, la piel del karst. Una fracción significativa de las especies de copépodos encontradas (9 especies en Eslovenia y 3 en Virginia Occidental) se presentaron en una extensión linear máxima de 100 m. Estas y otras distribuciones localizadas resultaron probablemente de colonización del epikarst por poblaciones superficiales ancestrales en una sola localización, con una expansión lateral subsiguiente en la dirección de flujo epikárstico. Esto sugiere que la distribución de copépodos podría tener un uso potencial para trazar rutas de flujo principales en epikarst sin tener la necesidad de inyectar colorantes u otros trazadores.相似文献
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L. Gasperini F. Alvisi G. Biasini E. Bonatti G. Longo M. Pipan M. Ravaioli R. Serra 《地学学报》2007,19(4):245-251
The so‐called ‘Tunguska Event’ refers to a major explosion that occurred on 30 June 1908 in the Tunguska region of Siberia, causing the destruction of over 2000 km2 of taiga, globally detected pressure and seismic waves, and bright luminescence in the night skies of Europe and Central Asia, combined with other unusual phenomena. The ‘Tunguska Event’ may be related to the impact with the Earth of a cosmic body that exploded about 5–10 km above ground, releasing in the atmosphere 10–15 Mton of energy. Fragments of the impacting body have never been found, and its nature (comet or asteroid) is still a matter of debate. We report results from the investigation of Lake Cheko, located ∼8 km NNW of the inferred explosion epicenter. Its funnel‐like bottom morphology and the structure of its sedimentary deposits, revealed by acoustic imagery and direct sampling, all suggest that the lake fills an impact crater. Lake Cheko may have formed due to a secondary impact onto alluvial swampy ground; the size and shape of the crater may have been affected by the nature of the ground and by impact‐related melting and degassing of a permafrost layer. 相似文献
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