The regeneration potential and conservation of excelsa coffee, coffea liberica w. bull var. Dewevrei (de wild. & t. Durand) lebrun, in selected sites of Uganda

Abstract

Sustainability of the coffee sector and livelihood of the communities that are dependent on this crop in Uganda will require exploration of nature-based solutions as climate continues to change. This study intended to assess the regeneration potential and conservation of wild excelsa coffee in selected sites of Uganda. The aim was to investigate excelsa coffee natural stock and recruitment capability and its potential for on-farm growing. Five study areas previously known or expected to harbor excelsa coffee were surveyed but, only Zoka Central Forest Reserve and Semuliki National Park had wild excelsa coffee sighted. Forty-seven quadrats of 20 m x 20 m were used for measurement of trees with >10cm diameter at breast height (DBH). In the quadrat were nested smaller ones of 10 m x 10 m, 5 m x 5 m and 2 m x 2 m for measurement of poles, saplings and seedlings respectively. In the same quadrat of 20m x 20 m, all plant species were identified and, unidentified ones collected as vouchers. The stand curves of both Semuliki and Zoka exhibited an Inverse-J curve implying healthy populations of Excelsa coffee that can sustain themselves through natural regeneration. The large number of seedlings dominated over the mature excelsa coffee trees in all study areas. In Ziroobwe farms, an irregular inverted J curve, a fairly good regeneration status was obtained.The number of seedlings was greater than saplings, thus showing a healthy population. The plant species closely associated with excelsa coffee in Zoka CFR were: Cola gigantea, Rinorea dentate, Cordia africana, Argomuellura macrophylla, Coffea canephora and Olyra latifolia. In Semuliki NP, it was associated with Desplatsia dewevrei, Marantochloa purpurea,Celtis mildbraedii Elaeis guineensis and Markhamia lutea plants species. In Ziroobwe Farms, it was associated with; Milicia exclesa, Argeratum conyzoides, Cordia africana, Coffea canephora and Markhamia lutea plants species. Settlement, logging and agriculture were the leading threats to conservation in Zoka Central Forest Reserve and Semuliki National Park. Generally, sustainable regeneration status of excelsa coffee was exhibited in Zoka Central Forest Reserve and Semuliki National Park. In Ziroobwe farms, the pattern was not definite, probably owing to management practices by the farmers who take interest in agronomical aspects such as spacing and how these influence yield. The population of coffee gives a high chance for breeding. Priority should focus on both in situ andex situ conservation strategies.