Invasive plant species management for sustainable ecosystem conservation in the Ngorongoro ecosystem, Tanzania

With the increasing human population and mobility, dispersal of exotic invasive plants has rapidly grownover the past three centuries in both temperate and tropical areas. Weed control has been a great challenge in farmlands and rangelands with application of traditional mechanic control methods and chemical herbicides rather than biological control methods. Our project aims at devising and testing an environmentally friendly, integrated method to control Tagetesminutaand Gutembergiacordifoliainvasive plant species in the Ngorongoro Conservation Area (NCCA), Tanzania.We plan to assess plant species richness and diversity under the influence of T. minutaand G. cordifoliain order to determine the most abundant native plant species as a potential tool to outcompete the invasives in the NCAA. We further want to study whether T. minutaand G. cordifolia is influenced by soil N, P, K, Ca, Mg, and pH levels in the NCAA. We experimentally test the competitive interaction of T. minutaand G. cordifolia with the most abundant native species under a uniform environmental condition (similar level of NPK) and rainfall regime. Further, we test the allelopathic effect of Desmodiumspp root and leaf crude extracts on the germination and growth of T. minutaand G. cordifolia in the greenhouse. Our study will provide innovative and environmentally friendly tools to suppress invasive plant species, particularly in protected areas where the use of herbicides is not allowed and not recommended.