Logging impact on Amazonian white-sand forests: perspectives from a sustainable development reserve

Overexploitation is one of the main causes of biodiversity loss and local extinction. In the Brazilian Amazon, the intensive use of high-value timber species is leading to a decline in their populations. When in decline, these species can be replaced by less valuable and more common ones that are more feasible to exploit. We conducted interviews with residents of two communities in a sustainable development reserve in central Amazonia, and used free lists and the cognitive salience index (S) to assess the perceptions of residents regarding the occurrence and purpose of timber exploitation, and to identify possible endangered species in white-sand and terra-firme forests. In addition, to infer possible consequences of logging, we assessed the current population status of timber species cited by residents in forest-plot inventories carried out within the reserve. S-index values and interviewee reports suggested an intensive use of terra-firme timber species and an apparently recent increase in the exploitation of white-sand species, which did not use to be exploited because of their relatively low commercial value. The inventories showed that the white-sand timber species have high relative densities and low S values in contrast to the terra-firme species, which mostly have low relative densities and high S values. Our results highlight the need to identify and monitor relevant timber species in both terra-firme and white-sand forests, and to increase the involvement of the local community in the development of logging management practices. (AU)

Composição de óleos essenciais de Dicypellium manausense, Mezilaurus duckei, Mezilaurus itauba e Pleurothyrium vasquezii, quatro espécies amazônicas da família Lauraceae / Composición de aceites esenciales de Dicypellium manausense, Mezilaurus duckei, Mezilaurus itauba y Pleurothyrium vasquezii, cuatro especies de Lauraceae de amazónia / Você quis dizer: Composição de óleos essenciais de Dicypellium manauense, Mezilaurus duckei, Mezilaurus itauba e Pleurothyrium vasquezii, quatro espécies amazônicas da família Lauraceae Composition of essential oils manausense Dicypellium, Mezilaurus duckei, Mezilaurus Itauba and Pleurothyrium vasquezii four Amazonian species of the Lauraceae family

Essential oils obtained from the aerial parts of Dicypellium manausense, Mezilaurus duckei, Mezilaurus itauba and Pleurothyrium vasquezii collected at the Ducke Forest Reserve (Manaus, Brazil) were obtained by hydrodistillation and analyzed by CG-FID and GC-MS. Essential oil yields ranged from 0.1 to 0.2 percent (w/w of dry material). The major components were beta-caryophyllene in the leaves of D. manausense (39.5 percent), leaves and branches of M. duckei (32.6 and 18.4 percent, respectively) and branches of M. itauba (51.8 percent); and germacrene D in the leaves of D. manausense (6.7 percent), branches of M. itauba (9.1 percent) and leaves and branches of P. vasquezii (15.6 and 8.0 percent, respectively). This paper describes for the first time the composition of these essential oils.

Os óleos essenciais obtidos das partes aéreas de Dicypellium manausense, Mezilaurus duckei, Mezilaurus itauba e Pleurothyrium vasquezii coletadas na Reserva Florestal Ducke (Manaus, Brasil) foram obtidos por hidrodestilação e analisados por CG-DIC e CG-EM. Os rendimentos dos óleos variaram de 0,1 a 0,2 por cento (m/m de material seco). Os principais componentes foram beta-cariofileno nas folhas de D. manausense (39,5 por cento), folhas e galhos de M. duckei (32,6 e 18,4 por cento, respectivamente) e galhos de M. itauba (51,8 por cento) e germacreno D na folhas de D. manausense (6,7 por cento), galhos de M. itauba (9,1 por cento) e folhas e galhos de P. vasquezii (15,6 e 8,0 por cento, respectivamente). Este trabalho descreve pela primeira vez a composição desses óleos.