Earth's Deserts - Research Paper Example

Deserts Introduction: The worldwide distribution of deserts depends on the atmosphere and air circulation in the area. For the same reason, most of the deserts are found in North and South latitude lines of 30˚.The climate in these regions is dominated by large amount of sunlight, little rain and high rates of evaporation (Cunningham n.d.). The deserts of the world occur in six major biogeographically divided regions. The Afrotropic deserts are present in the sub-Saharan parts of Africa, in countries like Algeria, Chad, Egypt etc. where the Sahara desert covers 10% of African continent. The southern part of Arabian Peninsula includes countries like UAE, Oman, Yemen and Saudi Arabia. Australia has the Australasian deserts which are made out of lowland ecological regions marked by intense aridity. The Indo-Malay region consists of two deserts: the Indus Valley and the Thar. The area includes Pakistan, Indian etc. The Nearctic deserts are situated in the North America and cover an area of 1.04 million square miles. On the other hand South America has the Neotropic deserts (Desert Locations. (n.d.). The three ecological areas which divide the UAE include the deserts which form 80% of the area in the country. The deserts specially dominate the western area (United Arab Emirates 2008). The deserts in the UAE spread from Arabian Gulf coast to the vast unpopulated expanse of sand in the Rub al Khali or the Empty Quarter and moves on to cover the gravel plains near the Hajar Mountains in the east (Desert Locations. (n.d.). Deserts have a major ecological importance. If rainfall decreases in the desert areas, the probability of cross boundary dust storms will increase. 50-70% of the dust particles originate from deserts of North Africa and 10-25% from deserts in Asia. The desert dust carries phosphorus and silicon which increases the growth of phytoplankton in the ocean. The desert sand increases productivity of marine ecosystems and of soils in the tropical region which lack nutrients, as seen in the Amazon basin where sand of the Sahara desert deposits. Desert also provides a doorway to the birds which do not belong to the desert, to migrate to other areas. Birds crossing the Sahara desert compete with the human population for the small oases which only occupies 2% of the area (GEO Year Book 2006). Main Topics: The most important abiotic factor which influences the desert ecosystem is rainfall. Mostly deserts are characterized by the fact that it experiences little or not rainfall. The deserts receive a total of less than 300 mm of rainfall per year, where a rainforest receives about 2000 mm. The lack of rain, and ultimately water in a desert makes the vegetation scarce and influences the adaptation of the plants and organisms. Plants such as cacti which are very common in a desert ecosystem have adapted to the scarcity of water by storing water in their stems. The saguaro cacti do not have very deep roots, allowing it to soak up rain and dew before it evaporates. Its spongy surface inside expands to hold more water (Cunningham n.d.). Bushes develop small and few leave, but long roots to adapt to the harsh conditions by conserving water. Some plants are short lived and grow only during when rain is available (Desert: Mission: Biomes. (n.d.). Temperature is another important factor which has a great impact on the ecosystem which ultimately is affected by another abiotic factor, sunlight. Temperature in the deserts reaches its extremes on a daily basis because there is no humidity in the desert air to block the Sun rays. The solar radiation received by desert areas is twice as much as received by humid areas and they also cool down twice as much at night. Mean annual temperature in North American deserts like Chihuahuan, Sonoran and Mojave for example is 20-25° whereas it can reach up to 49°. Minimum temperature here can drop to -18° as well. But temperatures can be so high that rain starts falling and gets evaporated whilst it reaches the ground (The desert biome. (n.d.). The desert ecosystem is influenced by soil also. The soil ranges from being very fine textured sand to rocky, coarse textured sand full of gravels. Hot and dry deserts have soil which drain water well and have no water on their surface. Due less weathering, the sand turns out to be coarse. The larger rocks are left behind as sand blows away. Semiarid deserts have soil with low salt concentration since they receive fewer rainfalls. The coastal areas have fine textured sands where leafy plants can grow and take in large amount of water. Their deep roots can also take in water from the soil (The desert biome. (n.d.). The biotic factors which make up the desert ecosystem include the many organisms specific to this ecosystem like Scorpions, Kangaroo rats, Camels, Lizards, Dung beetles etc and also the plants namely different Cacti like Organ Pipe Cactus, Barrel Cactus, Willow tree etc. Like every food chain, the food chain in the desert starts from the producer which can be a prickly pear cactus for example. The producer gets it energy from an abiotic factor i.e. the sunlight. The organisms which feed upon the producer are the primary consumers which in this case can be Harris’s antelope squirrel. The squirrel which feeds upon the fruit of the cactus derives its energy from it. The primary consumer can then be eaten by the secondary consumer, which can be a diamondback rattlesnake. The secondary consumer can be eaten by the tertiary consumer which can be the roadrunner. A quaternary consumer called the red tailed hawk can prey upon the roadrunner (Anderson, J. (n.d.). In this way these different trophic levels make up the desert ecosystem as seen in figure 1. Figure 1 In deserts small ecosystems thrive with mammals that develop a sensitive relationship with other organisms. Herbivores help spread seeds in the soil and other mammals dig out tunnels in it, in turn enriching it and also increasing water infiltration. ‘Off roading’ which is very popular on UAE deserts, destroys the soil and the vegetation on it by our cars. The most devastating part human play in destroying habitat is through remaking the habitat, for example after fires and overgrazing (Smith 2012). Dubai Desert Conservation Reserve aims to achieve sustainability of deserts in Dubai and it started a natural seed bank project wherein 6000 indigenous seeds and shrubs were planted. The 70 endangered Oryx which had been released in a protected area have evolved into a total of 400 Oryx now. Where in 2003 only 60 species of birds had been recorded, protected area measurements have increased the count to 126. The organization plans to teach the guides and tourists alike for greater sustainability. The Reserve limits the entry of people and vehicles wherever it can for minimal impacts and puts strictness on all the activities that strain the environment (Sustainability - Dubai Desert Conservation Reserve. (n.d.). Dubai Municipality in its press release stated that it updated its cleaning team and was successful in cleaning 581 tonnes of waste from 17 square kilometer camping area and distributed leaflets to spread awareness (Robertson 2014). Conclusion: Though the desert ecosystem gives us an impression that it may remain unharmed by human activities because of its desolation, desert continues to be at a threat today. It is our job to conserve its wildlife and vegetation which is teeming with life like any other ecosystem. We should not let the very intricate balance between its organisms get disturbed by our reckless attitude. It is our duty to conserve an ecosystem like desert which is distributed in different parts of the world and, apparently does not look of great ecological and economical importance. But the fact that it also serves an ecological role, we should make efforts to protect it for the greater sustainability and make good use of it like utilizing the solar power there, without harming it. References Cunningham, M. (n.d.). Earths Deserts: Definition, Distribution & Location. Retrieved December 10, 2014, from http://education-portal.com/academy/lesson/deserts-definition-and-distribution.html#lesson Desert Locations. (n.d.). Retrieved December 10, 2014, from http://www.defenders.org/desert/locations United Arab Emirates. (2008). Retrieved December 10, 2014, from http://www.fao.org/nr/water/aquastat/countries_regions/untd_arab_em/index.stm Desert Locations. (n.d.). Retrieved December 10, 2014, from http://www.defenders.org/desert/locations GEO Year Book. (2006). Retrieved December 10, 2014, from http://www.unep.org/geo/gdoutlook/005.asp Desert : Mission: Biomes. (n.d.). Retrieved December 10, 2014, from http://earthobservatory.nasa.gov/Experiments/Biome/biodesert.php The desert biome. (n.d.). Retrieved December 10, 2014, from http://www.ucmp.berkeley.edu/exhibits/biomes/deserts.php Anderson, J. (n.d.). Food Chains, Trophic Levels and Energy Flow in an Ecosystem. Retrieved December 10, 2014, from http://education-portal.com/academy/lesson/food-chains-trophic-levels-and-energy-flow-in-an-ecosystem.html#lesson Smith, B. (2012, September 9). Human Activities Reduce Desert Environment Diversity. Retrieved December 10, 2014, from http://www.redorbit.com/news/science/1112690144/desert-diversity-human-impact-090912/ Sustainability - Dubai Desert Conservation Reserve. (n.d.). Retrieved December 10, 2014, from http://www.ddcr.org/en/conservation/sustainability/ Robertson, C. (2014, June 5). Desertification: How UAE lands are under threat. Retrieved December 10, 2014, from http://gulfnews.com/gn-focus/world-environment-day/desertification-how-uae-lands-are-under-threat-1.1343175 Read More