Invasive species are new to the earth and pose threats to many lives and the environment. They are knows as
Alien Species because to many of us they are unknown. I chose five different types of Invasive Species particularly from South America and most of them that I found were from Brazil. I named five different criteria to specify each species such as: Organism name, description, areas found in, general impacts and geographical range.
The following name of the species are shown below along with the assessment with the criteria:
1. Scientific name:
Acacia longifolia
Organism type: Tree or shrub
Description: Small tree, bushy shrub, thin, size varies from 5-20 cm
Areas found in: Coast land, grasslands, shrub lands
General impacts: Reduction in bio-diversity, changes in ecosystem and in habitats
Geographical range: Argentina, Brazil, Colombia, India, Israel, Italy, Kenya, Java, Myanmar, New Zealand, Portugal, South Africa, Spain, Sri Lanka
2. Scientific name:
Acacia melanoxylon
Organism type: Tree
Description: Evergreen tree, 8-15 m, straight trunk, heavy branches
Areas found in: Coast land, agricultural areas, natural forests, grasslands, planted forests, shrub lands, estuarine habitats, urban areas, wetlands
General impacts: Replaces non-native tree vegetation (e.x. grassland), invades the understorey of relatively open pine and eucalypt plantations. They block water flow in river/streams if the tree falls.
Geographical range: Africa, Asia, Europe, India ocean, Pacific ocean, South America, United States
3. Scientific name:
Acanthus mollis
Organism type: Herb
Description: Perennial herb, upright hairless stems (one metre), leaves grow upto 50 cm.
Areas found in: Coast land, riparian zones, natural forests
General impacts: They form dense infestations under forest canopies. This supresses the growth and regeneration of native plant species.
Geographical range: Natural ecosystems in Australia and has spread to several other states.
4. Scientific name:
Achatina fulica
Organism type: Mollusc
Description: Narrow, conical shell which has a reddish-brown coloured, yellowish vertical markings, light-coffee is the common colour, adults are 20 cm long and their average weight is 32 g.
Areas found in: Coast land,agricultural areas, natural forests, planted forests, shrublands, urban areas, wetlands
General impacts: damages tropical agriculture where there is loss of crop yield caused by herbivory, spread of diseases through transmissions of plant pathogens.
Geographical range: Africa, United States, Asia, Pacific areas, Brazil
5. Scientific name:
Aedes aegypti
Organism type: Insect
Description: Female mosquito that relies on human blood and passes on her virus through the skin
Areas found in: tropic, suburban, urban, subtropic
General impacts: Causes yellow fever through transformation of viral blood from person to person. It is responsible for yellow fever virus and dengue virus
Geographical range: Asia, Europe, United States, South America, Australia and Africa
It is easy to eliminate any specie based on one criteria where it is weak at. It would be easy to eliminate
Acacia longifolia first because it is similar to
Acacia melanoxylon and it is not found in many areas as well as it does not have as strong impacts as
Acacia melanoxylon has.
Achatina fulica and
Aedes aegypti are very competitive because Achatina strongly effects the agriculture and Aedes has a tremendous effect on the human population. They both are widespread and it is very difficult to try to figure out which one is the most dangerous invasive specie.