Sunday, October 7, 2012

Hydrology and the Great Sand Dunes


From an untrained mind, The Great Sand Dunes National Park may not seem like a place in which hydrology is a main factor. However, from what I have learned in geography 1202, hydrology has a lot to do with the dunes existence. Typically, one may think that the sand dunes are home to an arid ecosystem where there is not much plant and animal life, but this is highly untrue. The water features are the whole reason plant and animal life exists at the dunes. Medano Creek, which I believe I mentioned in previous posts, may seem shallow on the surface, but it is actually just the top layer of a water system that exists below the surface. The sand dunes are home to a particularly high water table, which is the level to which water rises. The water that makes up the water table is what we consider groundwater which is water contained in the zone of aeration and the zone of saturation in a given area. Below the surface is also an aquifer, which is an underground layer of water containing materials (in this case I assume sand) in which ground water can be extracted and used. The Sand Dunes and surrounding mountain areas is hme to a recycled hydrology system in which the mountain creeks recycle capture sand, bring it to the valleys, where wind will then pick up and carry it to the dunes where it collects and piles, forming the gigantic dunes. A perfect example of why hydrology is so important to the duens and geography in general. The hydrology system is a huge factor in what created the dunes and is what maintains the dunes as we know them today!
 
 This picture serves as an explaination of the water table of the dunes and the aquifer that exists under Medano Creek. http://www.nps.gov/grsa/naturescience/hydrology.htm