Wednesday, February 08, 2017Register
 Biodiversity Hotspots

Biodiversity of Karst Habitats (Culver et al, 2001)
Biodiversity of Karst Habitats (Culver et al, 2001). Click on the image to go to the map.

Karst habitats contain unique environments that promote a high degree of endemism (a species may only live in one sinkhole, spring or cave). This means that karst habitats are hotspots for sensitive and threatened and endangered species.

Karst formations such as caves, sinkholes, springs and seeps provide habitat for hundreds of sensitive species, including many threatened and endangered species. Cave habitats support an estimated 1353 troglobitic (cave-dwelling) species in the United States, composed of 425 aquatic species and 928 terrestrial species (Elliot, 2000). Tables from Elliot lists all the extinct, threatened and endangered, candidate, and species petitioned for listing that are associated with cave habitats in the United States.  Among karst areas in the US, some have been identified as biodiversity hotspots. For instance, the Edwards Aquifer and the Ozarks Aquifer are among some of the most biodiverse karst areas in the US.  Karst species often act as as indicators of water quality in these important groundwater aquifers, thus protection of these species may serve to protect future drinking water supplies.

References:

Culver, D.C., Deharveng, L. Gibert, J. and I.D. Sasowsky (eds.), 2001. Mapping Subterranean Biodiversity.  Karst Waters Institute Special Publication 6.  West Virginia, Charlestown. 111 pgs.

Elliot,  W.R.  (2000).  Conservation of the North American Cave and Karst Biota.  Chap. 34, pp. 665-689inWilkens H., D.C. Culver, and W.F. Humphreys (eds.), Subterranean Ecosystems. Ecosystems of the World, 30.  Elsevier, Amsterdam. xiv 791 pp.


 Print   
 Karst Aquifers

The Karst Aquifer portal highlights the Edwards, Ozarks and Roswell aquifers. The portal features information and data, as well as an interactive mapping application, on groundwater and surface water conditions, precipitation, and threatened and endangered species in the Edwards, Ozarks and Roswell aquifers.

Karst and Pseudokarst Aquifers in the Continental United States [Figure: Houston Advanced Research Center utilizing data from the National Atlas Principal Aquifers dataset].

Karst and Pseudokarst Aquifers in the Continental United States [Figure: Houston Advanced Research Center utilizing data from the National Atlas Principal Aquifers dataset].


An Introduction to Karst
Karst is a unique land formation characterized by springs, caves, and sinkholes formed when carbon dioxide enriched water dissolves limestone and dolomite rock. Over 20% of the US land surface has underlying karst and because of the large fissures created by the dissolution of limestone and dolomite, large amounts of fresh water are trapped in these formations. Groundwater trapped in karst formations (aquifers) provides about 25% of the country's groundwater drinking supply. These large fissures assure that groundwater is quickly recharged; however, this also means karst aquifers are sensitive to contamination. The National Caves Association page on Cave Science describes the basic physical and chemical processes behind the formation of karst features such as aquifers and caves.

Threats to Karst Habitat and Biota
The Edwards Aquifer and the Ozarks Aquifer are among some of the most biodiverse karst areas in the US.  Karst species often act as as indicators of water quality in these important groundwater aquifers, thus protection of these species may serve to protect future drinking water supplies. Elliot lists the major threats to karst habitats. These are hydrological threats, which includes alteration of groundwater and surface water flows. Land development is another threat due to destruction, disturbance, or isolation of caves and cave species. Both nutrient loss and nutrient enrichment are threats to cave species because they alter cave biota. Exotic species such as fire ants and giant reed have been found in cave habitats and near karst springs. Chemical pollution in both aquatic and terrestrial cave and karst habitats can have devastating effects on karst species and threaten groundwater, even at small concentrations. Other threats include killing, disturbing and over-collection of species.

References:

Elliot,  W.R.  (2000).  Conservation of the North American Cave and Karst Biota.  Chap. 34, pp. 665-689inWilkens H., D.C. Culver, and W.F. Humphreys (eds.), Subterranean Ecosystems. Ecosystems of the World, 30.  Elsevier, Amsterdam. xiv 791 pp.


 Print   
Privacy StatementTerms Of UseCopyright 2011 Houston Advanced Research Center

BorderBoxedBlueBoxedGrayBlueSmall width layoutMedium width layoutMaximum width layoutMaximum textMedium textSmall textBack Top!