Plant harvest impacts and sustainability in Bwindi Impenetrable National Park, S.W. Uganda

Abstract

Sustainable utilization of forest resources has been widely adopted as a conservation strategy, but that sustainability has rarely been empirically tested. Plant resource extraction from Bwindi Impenetrable National Park (BINP) by local communities has been legalized and controlled in areas called multiple use zones (MUZs). Through a series of systematic transects and plots, we determined harvest impacts of two mostly harvested medicinal plants of Rytigynia kigeziensis VERDC.l and Ocotea usambarensis Engl in BINP. The plots were placed in MUZs and non‐MUZs. Data on biomass production and population dynamics were collected from the plots. We also analysed forest society records for the past 3 years to determine annual plant resource offtakes from BINP. Bark production of the two plants in MUZs and non‐MUZs are not significantly different, suggesting an insignificant change in bark production because of bark harvest. Annual bark harvests of the two plants are between 0.26–1.64% of available bark stock. These are too low to cause any noticeable negative impacts and are sustainable. Annual bark harvest of R. kigeziensis and O. usambarensis should be increased from the original 1% to about 3% of available bark stock to allow more involvement of the marginalized poor people like Batwa in BINP.

Impact assessment of the harvest of a medicinal plant (Anadenanthera colubrina (Vell.) Brenan) by a rural semi-arid community (Pernambuco), northeastern Brazil

“…It is commonly thought that the use of NTFPs has little impact on natural systems, but Peters (1994) considered that such use could be potentially unsustainable and dangerous. Some researchers assume that if a resource has been exploited by a given community over a long period of time this means that its extraction is inherently sustainable (Bitarilho et al 2006). However, such sustainability is hard to prove scientifically.…”

“…Some studies have shown that the collection of NTFPs may be unsustainable, even if this is undertaken by traditional populations (Kala 2000(Kala , 2005Pfab and Scholes 2004). The over-exploitation of such natural resources not only affects the different spheres of biological organisation (such as plant populations and ecosystems), but also affects the subsistence of social groups that depend on the diversity of available species in the environment (Bitarilho et al 2006). *Corresponding author.…”

“…Thus, it is impractical to access and monitor the ecological implications of human use for all species that are recognised as useful. Previous studies selected target species based on special characteristics such as their distribution, density and local importance (see Botha et al 2004;Pfab and Scholes 2004;Bitarilho et al 2006;Monteiro et al 2006b;Tabuti and Mugula 2007). For the present study, we chose a plant that is of particular importance to caatinga communities, Anadenanthera colubrina Vell.…”

Efeitos ecológicos da exploração de produtos florestais não madeireiros: uma revisão sistemática

“…Ademais, há estudos em que não foram observadas alterações em parâmetros reprodutivos, como no caso das taxas de recrutamento após a coleta de 100% dos caules subterrâneos (rizomas), espécie em que restos deixados no solo são capazes de rebrotar (Ghimire et al, 2005). Os efeitos no recrutamento foram também nulos com baixas taxas de extração, como a coleta de 0,26% a 1,64% do estoque total de cascas de árvores (Bitahiro et al, 2006).…”

“…De fato, duas avaliações relativas à extração em taxas entre 0,2 e 1,6% do total do estoque de cascas de espécies arbóreas não observaram alterações na taxa de crescimento três anos após cada coleta (Bitahiro et al, 2006). Ainda, a avaliação dos efeitos da coleta de caule de espécie arbustiva (Gaultheria shallon Pursh) mostrou que, após um ano, os espécimes explorados cresceram a taxas maiores do que espécimes intactos (Cocksedge & Titus, 2006).…”