Sunday, October 27, 2019
Riparian Ecosystem in the Semi-arid Southwest US
Riparian Ecosystem in the Semi-arid Southwest US Yi Rong Ecosystem project Geographic location The absolute location of the riparian ecosystem in the semi-arid Southwest of the US is 38à ° 11â⬠² 21â⬠³ S 109à ° 53 â⬠²07 â⬠³ W while its relative location is Southwest of the Colorado River. Climate The riparian ecosystem in this region registers an annual temperature of approximately 55F with an annual temperature range of 40F to 55F. The region receives a bi-modal precipitation regime with the highest precipitation experienced during the winter as well as during the summer monsoon winds. The annual precipitation can be recorded at between 16cm to 54cm. One of the major factors affecting the temperature and precipitation in this ecosystem is the proximity to the Colorado River which increases precipitation (Trexler 58). The thin cloud cover also influence the temperature as well as precipitation as it dictates the amount of direct sunlight on the moisture on the ground. The elevation of the ground is also another important factor that may influence precipitation and temperature. The higher the elevation, an area will experience higher the temperatures and lower precipitation. However, if the elevation is low then temperatures are expected to be lower while precipitation will be higher (Trexler 63). Extreme weather events in the southwest riparian ecosystem are mainly heat waves, floods and droughts and this can be attributed to the global climate change. This is because the climate of this region can be classified under a cold, semi-arid climatic zone (Doyle and Drew 13). This is characterized by relatively long drought periods as well as irregular precipitation, growing seasons that range from warm to hot and extended periods of winter which is sustained by freezing temperatures. Landforms and the land forming processes The riparian ecosystem here sits on a crustal rock that is surrounded by deformed Rocky Mountains together with Basin and Range Provinces (Raynolds 23). The main structures in this region are flexures, salt tectonic features, monoclines, vertical faults and volcanic. The folds here are broader rather than the characteristic tight folds found in orogenic belts. The wide areas of flat lying sedimentary rocks are divided by sudden bends of strata that form along the monoclonal folds formed nearly more than 600 million years ago. Normal faults dissect the ground in this area where normal faults are formed by tensional forces in which case the foot wall moves upwards relative to the hanging wall. These faults are more prevalent here because of the movement of the crustal blocks occurring in the Precambrian basement and the differential movement can be attributed to the differences in the elevation in this particular riparian ecosystem (Raynolds 39). Precambrian rocks are visible around th e region and they consist of gneiss, schist and younger sedimentary rocks. About 1.7 billion years ago, a north-south continental compression resulted in wrench faults areas, one being the Colorado River Lineament. Water and wind are the two key forces that can be attributed to the erosion of the ecosystem over the years (Adler 32). The main reason why water is the greatest force of the two is that the sun bakes the soil thereby making it so hard that it becomes difficult to absorb water. Therefore, when it rains, rain water flows freely with immense force. The vegetation in the area also doesnââ¬â¢t have deep laid roots to hold the soil together and this only adds to the problem (Lauenroth and Burke 51). As the free flowing water goes down, it creates flash floods that have great power to move rock boulders as big as automobiles. Ice also another erosion factor that cannot be ignored in this area. As faults are created between rocks, water seeps between these cracks and when temperatures are low, it turns to ice thereby expanding the cracks. When these faults get wide enough, pieces of rocks on the edges fall away and hit other rocks along the way thereby causing massive erosion effects. Th e topography of the ecosystem has characteristic different elevation levels. The vegetation in this area is mainly open-woodlands. The plants found here include cottonwoods, alders, cattails, plums as well as tall grass (Ralston 74). The Colorado River also makes an important part of the topography of the ecosystem. Surrounding the ecosystems are canyons and volcanic rocks whose surfaces have been eroded over the years mainly by water. Drainage patterns and stream systems The flow of the stream determines the forces that erode sediment and transport and deposit the same. This is important as it influences the various dimensions of aquatic systems in the ecosystem (Raynolds 53). The variance of stream flow also plays a major role in the occurrence of suitable environment and species abundance. The structural controls offered by the environment in the ecosystem act to dictate the various aspects of the streamââ¬â¢s flow such as its velocity and direction. Drainage patterns of streams in the ecosystem take the form of parallel and dendritic drainage patterns that are the most common in riparian ecosystems. As for the stream capacity, given the geology of the ecosystems and the level of erosion, the stream capacity in the ecosystem is high as the sediments from eroded soil and rocks transported by the stream is also high which translates to high power (Hazel 47). However, stream discharge in the ecosystem is relatively low as the width of the stream is narrow and wouldnââ¬â¢t support high stream discharge while the stream velocity is also low due to the many artificial islands formed by rocks found in the stream. These act to reduce the velocity of the stream greatly. The hard soil surface under the stream makes it difficult for water absorption and therefore when it rains, flash floods form easily while recurrence depends on the rain intervals during the year. Biome The biome in the ecosystem is classified according to the latitude within which the ecosystem is located. As a result of this, the climatic conditions brought about by the ecosystemââ¬â¢s latitude play a major role in determining the biome found in this area. Therefore, the dominant plants found in this particular ecosystem are mainly cottonwoods and open-woodlands. The animal species are the mule deer and the elk (Van Cole 16). Ecosystem characteristics, productivity, and services The productivity of the ecosystem can be seen from the dams and reservoir built in order to reduce the amount of erosion taking place in the ecosystem (Yaffee 61). This has received positive results as erosion has reduced greatly. On productivity, the ecosystem acts as a park ecosystem and local tourists can go and enjoy the different flora and fauna the ecosystem has to offer. Habitat/s The Riparian habitats are defined by different plants that depend on an integral hydrological regime. It is a case whereby the groundwater is sustained and surface flows that are natural occur. Plant and animal communities An assemblage of animal and plant communities is what define Riparian ecosystems and the presence of these communities attribute directly or indirectly to stream induced or interrelated factors. A greater diversity of animals and plants are supported by the Riparian ecosystems than the upland habitats. Food web and food chains In relation to the food web and chains, it is clear that approximately 80 percent of sensitive vertebrate species depend on aquatic habitants in their life cycle. Example of an animal and its niche There are western screech-owls, which have a niche at the moist woodlands that are found along the lakes and streams. Example of a symbiotic relationships A significant symbiotic relationship is between the star-flowered Solomonââ¬â¢s-seal with the moist shady woodlands that are found along the streams. Human-Land relationships Deforestation and animal grazing are some of the human activities that are taking place in the ecosystem. Ecosystem status Currently, the ecosystem is in a threatened/endangered status as the acts of animal grazing and deforestation are rampant within the area. A practical conservation strategy that has been adopted is the Conservation Reserve Program, which has been redesigned with the purpose of providing priority to areas that are stream buffer zones. Works Cited Adler, Robert W. Restoring Colorado River Ecosystems: A Troubled Sense of Immensity. Washington: Island Press, 2007. Web. Bainbridge, David. A Guide for Desert and Dryland Restoration: New Hope for Arid Lands. Washington: Island Press. 2012. Print. Doyle, Mary, and Cynthia A. Drew. Large-scale Ecosystem Restoration: Five Case Studies from the United States. Washington: Island Press, 2008. Web. Folliott, Peter and Leonard F. DeBano. Riparian Areas of the Southwestern United States: Hydrology, Ecology, and Management. Florida: CRC Press. 2003. Print. Hazel, Joseph E. Monitoring Fine-Grained Sediment in the Colorado River Ecosystem, Arizona: Control Network. S.l.: Bibliogov, 2013. Print. Kaiser, James. Grand Canyon: the Complete Guide. Ringgold, Ga.: Destination Press, 2011. Print. Lauenroth, William K, and Ingrid C. Burke. Ecology of the Short grass Steppe: A Long-Term Perspective. Oxford: Oxford University Press, 2008. Web. Ralston, Barbara E. A Vegetation Database for the Colorado River Ecosystem from Glen Canyon Dam to the Western Boundary of Grand Canyon National Park, Arizona. Flagstaff, Ariz.: Northern Arizona University, 2007. Print. Raynolds, Robert G. Roaming the Rocky Mountains and Environs: Geological Field Trips. Boulder, Colo: Geological Society of America, 2008. Print. Trexler, Joel. Monitoring Ecosystems. Washington: Island Press. 2003. Print. Van, Riper C, and Mark K. Sogge. The Colorado Plateau Iii: Integrating Research and Resources Management for Effective Conservation. Tucson: University of Arizona Press, 2008. Print. Van, Riper C, and Kenneth L. Cole. The Colorado Plateau: Cultural, Biological, and Physical Research. Tucson: University of Arizona Press, 2004. Print. Yaffee, Steven L. Ecosystem Management in the United States: An Assessment of Current Experience. Washington, DC: Island Press, 1996. Print.
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.