Nut Production in Bertholletia excelsa across a Logged Forest Mosaic: Implications for Multiple Forest Use

Abstract

Although many examples of multiple-use forest management may be found in tropical smallholder systems, few studies provide empirical support for the integration of selective timber harvesting with non-timber forest product (NTFP) extraction. Brazil nut (Bertholletia excelsa, Lecythidaceae) is one of the world’s most economically-important NTFP species extracted almost entirely from natural forests across the Amazon Basin. An obligate out-crosser, Brazil nut flowers are pollinated by large-bodied bees, a process resulting in a hard round fruit that takes up to 14 months to mature. As many smallholders turn to the financial security provided by timber, Brazil nut fruits are increasingly being harvested in logged forests. We tested the influence of tree and stand-level covariates (distance to nearest cut stump and local logging intensity) on total nut production at the individual tree level in five recently logged Brazil nut concessions covering about 4000 ha of forest in Madre de Dios, Peru. Our field team accompanied Brazil nut harvesters during the traditional harvest period (January-April 2012 and January-April 2013) in order to collect data on fruit production. Three hundred and ninety-nine (approximately 80%) of the 499 trees included in this study were at least 100 m from the nearest cut stump, suggesting that concessionaires avoid logging near adult Brazil nut trees. Yet even for those trees on the edge of logging gaps, distance to nearest cut stump and local logging intensity did not have a statistically significant influence on Brazil nut production at the applied logging intensities (typically 1–2 timber trees removed per ha). In one concession where at least 4 trees ha-1 were removed, however, the logging intensity covariate resulted in a marginally significant (0.09) P value, highlighting a potential risk for a drop in nut production at higher intensities. While we do not suggest that logging activities should be completely avoided in Brazil nut rich forests, when a buffer zone cannot be observed, low logging intensities should be implemented. The sustainability of this integrated management system will ultimately depend on a complex series of socioeconomic and ecological interactions. Yet we submit that our study provides an important initial step in understanding the compatibility of timber harvesting with a high value NTFP, potentially allowing for diversification of forest use strategies in Amazonian Perù.

Revisiting the ‘cornerstone of Amazonian conservation’: a socioecological assessment of Brazil nut exploitation

“…In Peru, harvesting of Brazil nut is both a financially attractive and complementary activity in ecotourism forest concessions (Kirby et al 2010) and biophysically compatible with low intensity timber harvesting (Rockwell et al 2015). Across its vast geographical range, the Brazil nut tree coexists with dozens of timber species (ter Steege et al 2013;Fauset et al 2015).…”

“…Across its vast geographical range, the Brazil nut tree coexists with dozens of timber species (ter Steege et al 2013;Fauset et al 2015). And although integrated timber-Brazil nut management can be hampered due to policy, economic and technical constraints (Guariguata et al 2009;Cronkleton et al 2012b;Duchelle et al 2012;Rockwell et al 2015), many of these tradeoffs are not insurmountable. To this end, such integrated management approaches need further development from a technical, regulatory and educational standpoint .…”

“…2a) of up to 5 m (de Salomão 1991; Peres et al 2003;Brienen and Zuidema 2006;Kainer et al 2007;Rockwell et al 2015). They form high density groves (up to …”

“…Yet at present it is not known under which landscape configurations fruit yields are to decrease via potential disruption of inter-tree pollen transfer. In any case, at low timber harvesting intensities in closed-canopy forest, Brazil nut tree fecundity seems unaffected (Rockwell et al 2015). Although promising efforts to intensify Brazil nut production through plantations do exist most prominently in central Brazil, yields are low (probably related to the specialized nature of their pollinators and type of planting material) thus making both market and volume shares currently insignificant basin-wide (Homma et al 2014).…”

Analyzing multilevel governance in Peru: Lessons for REDD+ from the study of land-use change and benefit sharing in Madre de Dios, Ucayali and San Martin

“…However, by 2007 the volume allowance was abolished based on the argument that "there were no credible and accurate scientific indicators to justify an impact of timber extraction on nut harvests" . New technical norms associated with forest regulations in 2016 permit the harvest of up to two timber trees per hectare in Brazil nut concessions in the Madre de Dios region, based on research from 2012-2015 studying the impact of selective logging on Brazil nut production as a way to optimize multiple forest uses (Rockwell et al 2015 …”