摘要
Osyris lanceolata is heavily and illegally exploited in East Africa for its essential oils, yet little is known about its population status and ecological requirements. This study examined its population structure and environmental factors influencing its distribution in the semi-arid Karamoja sub-region, Uganda. We surveyed 388 plots (5 m radius) at different altitudes, recording life stages, stem diameters, and regeneration patterns, and analyzed soil samples. Multivariate analyses, including Canonical Correspondence Analysis (CCA), Detrended Correspondence Analysis (DCA), Non-metric Multidimensional Scaling (NMDS), and Multiple Regression Modeling (MRM), identified key environmental factors affecting its distribution. Findings show that O. lanceolata populations in Moroto, Nakapiripirit, and Amudat districts are severely degraded due to overexploitation. The species is primarily regenerating through coppicing rather than seedlings, with an exploitation intensity of 56.6%. Population densities are low, distribution is irregular, and sustainable harvesting is not viable. Soil properties, particularly Ca2+, N, P, K+, Na+, and organic matter, significantly influence its abundance. Conservation efforts should focus on identifying suitable provenances for genetic preservation and plantation establishment. Areas with at least 9 trees per hectare in Moroto, Nakapiripirit, and Amudat could serve as potential sites for ex-situ plantations. Further research should explore how biotic interactions, genetic diversity, and morphology affect oil yield and quality to support restoration, breeding, and domestication initiatives.
Osyris lanceolata is heavily and illegally exploited in East Africa for its essential oils, yet little is known about its population status and ecological requirements. This study examined its population structure and environmental factors influencing its distribution in the semi-arid Karamoja sub-region, Uganda. We surveyed 388 plots (5 m radius) at different altitudes, recording life stages, stem diameters, and regeneration patterns, and analyzed soil samples. Multivariate analyses, including Canonical Correspondence Analysis (CCA), Detrended Correspondence Analysis (DCA), Non-metric Multidimensional Scaling (NMDS), and Multiple Regression Modeling (MRM), identified key environmental factors affecting its distribution. Findings show that O. lanceolata populations in Moroto, Nakapiripirit, and Amudat districts are severely degraded due to overexploitation. The species is primarily regenerating through coppicing rather than seedlings, with an exploitation intensity of 56.6%. Population densities are low, distribution is irregular, and sustainable harvesting is not viable. Soil properties, particularly Ca2+, N, P, K+, Na+, and organic matter, significantly influence its abundance. Conservation efforts should focus on identifying suitable provenances for genetic preservation and plantation establishment. Areas with at least 9 trees per hectare in Moroto, Nakapiripirit, and Amudat could serve as potential sites for ex-situ plantations. Further research should explore how biotic interactions, genetic diversity, and morphology affect oil yield and quality to support restoration, breeding, and domestication initiatives.
作者
Ben Belden Mugula
Samuel Kuria Kiboi
James Ireri Kanya
Harald Meimberg
Manuel Curto
Paul Okullo
Anthony Egeru
Jenipher Biira Salamula
Stephen F. Omondi
Ben Belden Mugula;Samuel Kuria Kiboi;James Ireri Kanya;Harald Meimberg;Manuel Curto;Paul Okullo;Anthony Egeru;Jenipher Biira Salamula;Stephen F. Omondi(Department of Biology, Faculty of Science and Technology, University of Nairobi, Nairobi, Kenya;Department of Agricultural and Environmental Sciences, Bugema University, Kampala, Uganda;Institute of Integrative Nature Conservation Research, Department of Ecosystem Management, Climate and Biodiversity, BOKU University, Vienna, Austria;BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Campus de Vairo, Vairo, Portugal;National Fisheries Resources Research Institute, National Agricultural Research Organisation (NARO), Jinja, Uganda;College of Environmental and Agricultural Sciences, Makerere University, Kampala, Uganda;Institute of Development Policy (IOB), University of Antwerp, Antwerp, Belgium;Kenya Forestry Research Institute, Nairobi, Kenya)
