GLOBAL CHANGE AND BIOLOGICAL INVASION

The global change and biological invasion are currently the main topics in ecology around the world. Global change and biological invasion is a world wide problem. Both are said to have environmental and communal inference. Different studies suggest that Climate change which is caused mainly by human activities may directly or indirectly aid the success of the biological invaders. [1]

Global change includes numerous environmental and ecological alterations that occurs world wide. It includes change in ecology and environment as well as climatic composition of the atmosphere. Biological invaders are referred to plant and animal species not endemic to the particular country. [2 and 3]

Rising in the atmospheric Carbon Dioxide (CO2) plays a role in the success of many invaders. According to Dukes and Mooney 1999, there is a positive respond by invasive plants where CO2 is prominent. For example, the lantana camara which is an indigenous in the south and Central America is known to have tolerance in many environmental conditions even where CO2 is increased. The Bromus rubens grass is known to grow where there are warmer climates and they are favoured by increased CO2. They are well adapted to fire and they increase their dominance where fire occurred [1]. According to the GISP the effects of invasive alien species are worsened by global change and chemical and physical disturbance to species and ecosystems [4]

Land use change is also playing a role in the increase in success rate of the invasive species. In disturbed such as farming areas and disturbed areas for development is more prone to invasion. Most invasive species have competitive capabilities and they can grow and reproduce faster than the native species. The lantana camara are able to release chemicals that prevent other plant species from growing. This process is known as allelopathic mechanism. The lantanas are able grow forming a dense thickets which also prevent other from growing. [1 and 4]

Different studies show that there evidence that global change is playing a role in biological invasion and global change. It is how ever recommended for more studies to be done on global change and biological invasion. More observational and experimental studies must be undertaken to deal with this problem.

Reference:

1. Dukes JS and Mooney HA. 1999. Does global change increase the success of invaders? Trends Ecol Evol 14: 135-39.
2. Wikipedia contributors. Global change [Internet]. Wikipedia, The Free Encyclopedia; 2006 Jun 11, 19:53 UTC [cited 2006 Jul 11]. Available from: http://en.wikipedia.org/w/index.php?title=Global_change&oldid=58080847.
3. Wikipedia contributors. Invasive species [Internet]. Wikipedia, The Free Encyclopedia; 2006 Jul 9, 04:21 UTC [cited 2006 Jul 10]. Available from: http://en.wikipedia.org/w/index.php?title=Invasive_species&oldid=62830037
4. GSIP. Africa invaded: Lantana [Internet]. [Cited 2007 Jan 24]. Available from
http://www.gisp.org/casestudies/showcasestudy.asp?id=57&MyMenuItem=casestudies&worldmap=&country=

Mr Lufuno Mukwevho
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