Tree species diversity and abundance in coffee farms adjacent to areas of different disturbance histories in Mabira forest system, central Uganda

Abstract

Coffee production in Uganda is done on small-scale farms containing a very significant tree component. However, there is little information on how tree species abundance, richness and diversity change in coffee farms as distance from forest changes. The main objectives of this study, therefore, were to assess (a) abundance and (b) diversity of tree species in the coffee production systems in proximity to disturbed and undisturbed forest around Mabira forest, one of Uganda's Robusta coffee-growing areas. Seventy-nine 0.1 ha plots were established in nine villages close to undisturbed and disturbed forest, and over 5 km from the forest. A total of 875 trees belonging to 63 species were recorded. There was significant similarity in species composition among the three study sites (analysis of similarity R = 0.09, p < 0.01; analysis of variance: F3,12 = 0.353, p = 0.79). Non-metric dimensional scaling supported these findings (stress value = 0.224 at k = 2) and showed that tree species composition in the three proximity categories was very similar. These results demonstrate that tree species composition and diversity is similar in coffee farms regardless of their distance from the nearest natural forest and forest exploitation history. (Résumé d'auteur

Typology of coffee-based agroforestry systems in the semi-deciduous forest zone of Togo (West Africa)

“…Furthermore, other observed groups, especially P. americana and C. sinensis in association with other species in coffee farms, have also been reported by authors who have worked in CAFS (Gwali et al, 2015;Gonzalez-Zamora et al, 2016). These fruit species are associated with coffee trees, especially because of their high economic value (Davis et al, 2017).…”

The effect of Broussonetia papyrifera invasion on the regeneration of selected native timber species in a tropical moist forest in Uganda

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Dynamics of native tree structure and diversity in coffee agroforest: a case study from Central Western Ghats

“…The major cause for this shift is due to the current rules of harvest (tenure systems/tree rights) and sale of trees which does not permit harvest and sale of native trees but promotes the fast-growing exotic tree species like silver oak. Earlier studies by Gwali et al (2015) reported that Artocarpus heterophyllus, Carica papaya, Albizia chinensis and Persea americana are more dominant tree species in coffee farms. Another major reason for lower populations of other native trees could be due to large canopy size leading to higher shading of coffee and higher costs of pruning and restrictions in harvest and sale.…”