Invasive plant species and their disaster-effects in dry tropical forests and rangelands of Kenya and Tanzania

Invasive plants are a hazard in the tropical dry forests and rangelands of East Africa. Although often not reported, they have increasingly created disasters that have a#ected the environment and socio-economic wellbeing of communities inhabiting these dry regions. $is paper reports on the key invasives in the drylands of Kenya and Tanzania and their e#ects, and suggests some disaster risk reduction (DRR) strate gies. $e study was largely based on secondary data analysis and supported by surveys in the a#ected drylands. $e %ndings show ten key invasive plant species that a#ect the drylands. $eir disaster-e#ects vary and include: causing the death of livestock by poisoning and destroying livestock foliage, accelerating biodiversity loss via suppression of native plants, to increasing diseases by o#ering a breeding ground for mosquitoes and other insects that carry ailments like nagana and sleeping sickness. $e DRR initiatives include (1) having a prudent land use system that discourages activities like unplanned burning of drylands, (2) assessing and monitoring phytosanitary risks associated with introduced plant species, (3) strengthening national and local institutional capacities that enhance invasive species awareness and preparedness for disasters, and (4) enhancing early warning systems related to plant invasion.

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