Water hyacinth, scientifically known as Eichhornia crassipes, is an aquatic weed with several broad leaves and inflated leaf stalks, which belongs to the family Pontederiacease.
It is considered one of the world's worst aquatic weeds because of its ability to rapidly spread over and infest a wide variety of wetlands including ponds, rivers, dams, lakes and irrigation channels. Research has found that these weeds can double their mass in six to 15 days.
One of the regions in Africa that has been largely affected by this highly invasive weed is Lake Victoria. The first record of water hyacinth infestation in the lake was in the late 1980s and it is believed that the plant entered the lake from Rwanda through River Kagera.
Experts tried to eradicate it in vain and by the early 1990s, the detrimental effects arising from the infestation of water hyacinth in Lake Victoria were alarming, affecting the surrounding populations within the three East African countries that share the lake.
The weed has formed blankets in parts of the lake and as a result caused the development of impenetrable floating mats, which interfere with boat movement. Water transportation and local subsistence fishing surrounding the lake region has thus been significantly affected.
The weed has also been found to clog irrigation pumps and pipes in some regions surrounding the lake thus affecting the flow and supply of water.
Harmful insects such as mosquitoes also tend to settle in parts of the lake where water hyacinth is densely concentrated, since these weeds also hinder insecticide application. As a result, the incidence of conditions such as malaria, skin rashes, bilharzia, encephalitis, gastro intestinal disorders and schistosomiasis have intensified in these regions.
These plants also block light, contributing to de-oxygenated water bodies and in turn affecting aquatic organisms in Lake Victoria.
