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Anthropogenic disturbances, such as illegal harvesting and livestock browsing, often affect natural forests. However, the resulting tree species diversity, composition, and population structure have rarely been quantified. We assessed tree species diversity and importance value indices and, in particular, Balanites aegyptiaca (L.) Del. population structure, across 100 sample plots of 25 m × 40 m in disturbed and non-disturbed sites at the Dinder Biosphere Reserve, Sudan, from April 2019 to April 2020. We found that the tree species diversity in non-disturbed sites was more than double that of disturbed sites ( p < 0.001, T = 32.6), and seedlings and saplings comprised more than 72% of the entire tree population ( F 2,48 = 116.4, p = 0.034; F 2,48 = 163.2, p = 0.021, respectively). The tree density of B. aegyptiaca in the disturbed site was less than half that of the non-disturbed site ( p = 0.018, T = 2.6). Balanites aegyptiaca was seven times more aggregated in disturbed sites compared to more regularly spaced trees in non-disturbed sites ( T = 39.3 and p < 0.001). The poor B. aegyptiaca population status of the disturbed site shows that the conservation of this vulnerable species is essential for a sustainable management and utilization scheme.

Approaches to managing invasive plants is challenging, particularly in protected areas where conventional methods, such as chemical herbicide applications are limited. We studied the effects of varying densities of Cynodon dactylon on the growth and development of the invasive weeds Tagetes minuta and Gutenbergia cordifolia in northern Tanzania. We conducted pot and field plot experiments following a completely randomized block design that was replicated three times. Increasing densities of C. dactylon significantly reduced growth, leaf total chlorophyll, biomass and significantly increased leaf anthocyanin of both T. minuta and G. cordifolia invasives. Our results further showed that the critical density of C. dactylon to suppress the two invasive species is ≥ 8 plants/m 2 . We suggest that C. dactylon can successfully be used as an alternative eco-friendly and sustainable approach for managing invasive weeds, such as T. minuta and G. cordifolia . This management technique can additionally improve forage production and biomass for wild and domestic herbivores in the affected areas.