Species Essay Example | Topics and Well Written Essays - 750 words

Species - Essay Example The US alone estimate that invasive species cost its economy approximately $138 billion per year (Pimentel, Lach, Zuniga & Morrison, 1999). The introduction of this non-native species has proved to have dire consequences to the environments and ecosystems. One invasive species that has had severe costs to host nations is Bufflegrass. As an invasive species it has now become naturalized in the Americas, Australia, Hawaii and Mexico to name a few. Bufflegrass thrives in low rainfall a condition which makes it the perfect species to introduce to arid countries and was first introduced in the US and Mexico to improve forage for cattle, Arizona and the Sonaran desert were the ideal ecosystems for the grass to grow. Bufflegrass is drought resistant so thrived in its native countries including Africa. The grass will withstand heavy grazing and so was introduced for this purpose so the conversion of forest, homogenous grassland and savanna to pasture for grazing created the ideal environment for this hardy grass to grow. However the problem lies in that this invasive grass has spread from cultivated areas to natural ecosystems at an alarming rate as it will grow in all soil types and including sandy and stony soils. Bufflegrass grows densely and so crowds out native plants of similar size and due to its ability to resist drought will remain dense even in dry years. It attacks native plants by its ability to win competition for natural resources such as water, space and soil nutrients so prevents homogenous plants from maturing and germinating and secondly it is highly flammable but resistant to fire, once a grass fire has occurred it is not unusual that only the Bufflegrass grows back. The Sonaran Desert evolved without fire as an ecological factor and most of its plants cannot tolerate it. The Bufflegrass populations in Saguaro National Park have quadrupled in size between 2002 and 2006 despite the outbreaks of several vastly spread fires (Bean & Betancourt, 2006). The economic factor is that with the increased risk of fires utility infrastructures are threatened, property may decrease in value as areas become known for fire hazards, insurance rates rise not to mention the cost to governments in having to find means of managing the invasive grass. There is also the cost of life involved, in November 2005 a man was burned to death in a Bufflegrass fire in Arizona Bibliography Bean, Travis M. & Betancourt Julio L. (2006) Bufflegrass in theS onoran Desert: Can we prevent the unhinging of a unique American ecosystem The Plant Press THE ARIZONA NATIVE PLANT SOCIETY VOLUME 30, NUMBER 1 (Retrieved on 18th November 2008) http://aznps.org/PDFs/PlantPress/PP30.1.pdf Pimentel, D, Lach, L, Zuniga R, & Morrison, D. (1999) Environmental and Economic Costs associated with Non-Indigenous Species in the United States College of Agriculture and Life Sciences, Cornell University, Ithaca