The impact of selective logging and clearcutting on forest structure, tree diversity and above‐ground biomass of African tropical forests

Abstract

Tropical deforestation is well known to have serious negative consequences for biodiversity, terrestrial carbon sinks and the balance of atmospheric greenhouse gases. By contrast, selective logging of tropical forests is often regarded as having a lesser impact on the ecosystem particularly in long terms, even though there have been few critical evaluations of the practice, particularly in Africa. We compared field data from 511 plots in the tropical forest of Sierra Leone, Ghana, Cameroon and Gabon. These plots were subject to different forest management practices: no recent logging (primary forests), selective logging (up to 30 years old) and re‐grown secondary forests post clear‐cutting (at least 20 years ago). Our findings suggest that the vertical structure and plant richness of the selectively logged and secondary forests change in different amplitude from those of primary forests, but stem density and the prevalence of vine and weed species differ greatly. We show that the effects of selective logging are greater than those expected simply from the removal of commercial species, and can persist for decades. Selective logging, unless it is practiced at very low harvest intensities, can significantly reduce the biomass of a tropical forest for many decades, seriously diminishing aboveground carbon storage capacity, and create opportunities for weeds and vines to spread and slow down the ecological succession.

Logging disturbance shifts net primary productivity and its allocation in Bornean tropical forests

“…Although the logging intensity in this study and in Southeast Asia in general is probably higher than the global average, the biomass loss is comparable to what has been reported in Brazil (35%-57%, Berenguer et al, 2014) and Africa (20%-72%, Valentini et al, 2014;Gatti et al, 2015).…”

Evaluating the ability of community‐protected forests in Cambodia to prevent deforestation and degradation using temporal remote sensing data

“…Selective logging for valuable tree species is a leading cause of forest degradation in the countries of Southeast Asia, including Cambodia (Miettinen, Stibig, & Achard, 2014). This has an adverse impact on forest structure parameters such as stand-scale tree heights, AGB, gap fractions, and species composition (Asner et al, 2004;Gatti et al, 2015;Osazuwa-Peters, Chapman, & Zanne, 2015;Rutishauser, Hérault, Petronelli, & Sist, 2016). However, selectively decades (Gourlet-Fleury et al, 2013;Ngo et al, 2013;Osazuwa-Peters et al, 2015).…”

Does degradation from selective logging and illegal activities differently impact forest resources? A case study in Ghana

“…The West African forest belt is a biodiversity hotspot and a provider of fundamental ecosystem services, now degraded and reduced to a patchwork of forest fragments (CEPF 2003). Selective logging is possibly the primary cause of degradation in African forests with recognized impacts on carbon stocks (Cazzolla Gatti et al 2015, Hawthorne et al 2012) and fine root production (Ibrahima et al 2010). In Ghana, concessions interest more than half of the reserves (Hawthorne & Abu-Juam 1995).…”