Introduction
Deserts is are regions of the Earth that receive less than 10 inches of water a year with little or no precipitation at all. They are often the hottest and most inhospitable places and constitute to an estimated 33 percent or one third of the Earth’s total land mass. Clusters of deserts are found around the Tropic of Cancer and the Tropic of Capricorn, where the sun's angle at solar noon is closest to ninety degrees overhead at the Equinox. Some famous deserts are the Gobi and Taklamakan deserts in Asia, the Sahara in northern Africa, and the Great Sandy and Simpson deserts in Australia.
Structure
The desert ecosystem is classified according to biotic and abiotic components. The various biotic components are represented into three functional groups: producer, consumers and decomposers. The producers are mainly shrubs or bushes, some grasses and a few trees. Most of plant species that can survive the desert are succulents, which mean they can store water. Others have seeds that lay dormant until a rain awakens them. The most famous desert plant is the cactus. The consumers include insects and arachnids, reptiles, birds and mammals. The animals that live in the desert are conditioned to endure extreme temperatures with minimal water. The most famous desert animal is the Camel or “the cars of the desert”. Camels are great for transportation because they use very little water. Camels can withstand very high temperatures without sweating. They also store fat in their humps for food. The decomposers, however, are very few. Due to poor vegetation the amount of dead organic matter is very less. The common decomposers are some bacteria and fungi, most of which are thermophile.
One abiotic component of desert is rainfall. Limited water a defining feature of desert ecosystems and their most profound environmental constraint. This means that animals and plants looking to survive in the desert must be able to live with little water for extended periods of time. Another is abiotic component is temperature. A desert that is hot during the day may drop below zero degrees at night once the heat of the sun has left. Another component is soil types which vary from sandy and fine-textured to loose rock fragments, influencing a given location’s drainage as well as evaporation. Last component is sunlight that can be intense because of prevailing cloud-free conditions. The degree and intensity of sunlight in a given spot helps shape its microclimate and thus affects plants and animals.
Biogeochemical Cycle
Biogeochemical cycle is a series of movement and transformation of matter or substances within the biosphere, hydrosphere, lithosphere and the atmosphere which comes back to the starting point and which can be repeated. The cycle of matter involves biological, geological and chemical processes.
For example, the carbon cycle in desert is a continuous process that involves the desert plants absorbing carbon dioxide together with sunlight and water in the process called photosynthesis to make food and carbon rich compounds. When plants die, they decompose and release the carbon elements into the soil as nutrients. Then the carbon elements are absorbed by other plants. Desert animals also breathe out carbon dioxide and decompose upon death and the cycle continues.
Disturbance and Recovery
Sand storm is an example of naturally occurring disturbance in a desert ecosystem. Sand storm is defined as a meteorological phenomenon common in arid and semi-arid regions. It arises when a gust front or other strong wind blows loose sand and dirt from dry surface. It can transport and carry large volumes of sand unexpectedly thus affecting the ecosystem. The soil is displaced to another location forming a new dessert landscape burying many biotic characteristics with sands. Some plants are also uprooted and some animals may not be able to survive.
Another disturbance is called desertification that can occur naturally due to extreme droughts. But there are many situations where the process of desertification has been caused or accelerated by human activities. Desert border areas undergoing desertification will not simply convert into natural deserts. Disturbed and overused semi-arid zones are characterized by lower biodiversity than original. Therefore desertification will not simply increase the global area of deserts; it will create large tracts of devastated lands.
Natural Resources
The desert may seem like a wasteland that is devoid of life, but this dry earth has many buried treasures hidden within the sand that are useful natural resources. The most abundant natural resources are minerals such as copper, granite, mica and various types of clay. Desert plants are also natural resources that are used to make syrups, medicines and other products.
The best way human can act towards desert ecosystem recovery is by implementing sustainable resource management policies. Namibia, for example, was the first African country to incorporate protection of the environment into its constitution. The government together with nonprofit organizations and other entities, have restored populations of lions, cheetahs, black rhinos, zebras and other native wildlife to the world’s richest dry land. Through initiatives, such as ecotourism, restoration has generated sustainable income for their communities.
References
Desert Ecosystem: Types, Characteristic, Structure and Function of Desert Ecosystem. (2014, February 26). Retrieved from http://www.yourarticlelibrary.com/environment/ecosystem/desert-ecosystem-types-characteristic-structure-and-function-of-desert-ecosystem/28247/
Tuttle, S. (n.d.). Abiotic Factors of a Desert Ecosystem. Retrieved from http://www.ehow.com/info_8151693_abiotic-factors-desert-ecosystem.html
Biogeochemical cycles. (n.d.). Retrieved from http://www.eoearth.org/view/article/150616/
The Biogeochemical Cycles. (n.d.). Retrieved from http://death-valley-ecology.weebly.com/the-biogeochemical-cycles.html
Desert biome. (n.d.). Retrieved from http://www.eoearth.org/view/article/151704/
Rgensen, S. (2009). Ecosystem ecology (p. 239). Amsterdam, Netherlands: Elsevier.
Global Deserts Outlook. (n.d.). Retrieved from http://www.unep.org/geo/gdoutlook/102.asp
Namibia. (n.d.). Retrieved from www.worldwildlife.org/places/namibia
