|
Invasive Alien Plants (IAPs) are plants that are introduced into countries, and then out-compete the indigenous species. They are exotic trees, and plants that multiply easily and spread
into natural areas on their own where they do not belong.
IAPs pose a direct threat not only to South Africa’s biological diversity, but also to water security, the ecological functioning of natural systems and the productive use of land. They intensify the impact of fires and floods and increase soil erosion. IAPs can divert enormous amounts of water from more productive uses and invasive aquatic plants, such as the water hyacinth, effect agriculture, fisheries, transport, recreation and water supply.
Of the estimated 9 000 plants introduced to this country, 198 are currently classified as being invasive. It is estimated that these plants cover about 10% of the country and the problem is growing at an exponential rate.
Not all exotic species are invasive. Examples of invasive trees
are Port Jackson trees (mostly found in the Western Cape) and Red sesbania. There are many species of invasive
plants, of which some are trees or shrubs. One also finds invasive species among other types of creatures, such as
insects, birds, fish and mammals. Invasive species are undesirable because they compete with or threaten indigenous
species and they can increase the cost of agriculture or cause fire risk.
The fight against IAPs is spearheaded by the Working for Water (WfW) programme. This programme works in partnership with local communities, to whom it provides jobs, and also with Government departments including the Departments of Environmental Affairs and Tourism, Agriculture, and Trade and Industry, provincial departments of agriculture, conservation and environment, research foundations and private companies.
Since its inception in 1995, the programme has cleared more than one million hectares of invasive alien plants.
>> more information
|
