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)

Dos registros de Agaricales (Basidiomycota) exóticos en bosques nativos de la Patagonia argentina / Two records of exotic Agaricales (Basidiomycota) in native forests of the Argentinean Patagonia

Inocybe sindonia (Fr.) P. Karst. y Amanita rubescens Pers. son especies típicamente asociadas a bosques de Pseudotsuga menziesii (Mirb.) Franco y Pinus radiata D. Don respectivamente. Se reporta por primera vez su presencia en Argentina en bosques de Nothofagus de la Patagonia andina como resultado de la invasión de especies forestales introducidas como recurso maderero. I. sindonia fue colectado en bosques de N. dombeyi (Mirb.) Oerst. y A. rubescens en bosques de N. pumilio (Poepp. & Endl.) Krasser en áreas protegidas con invasión evidente de coníferas exóticas.

Inocybe sindonia (Fr.) P. Karst. and Amanita rubescens Pers. are species typically associated to Pseudotsuga menziesii (Mirb.) Franco and Pinus radiata D. Don respectively. Both species have been introduced in South America together with timber species plantations. Basidiomes of I. sindonia were found occurring under Nothofagus dombeyi (Mirb.) Oerst., while basidiomes of A. rubescens were found under N. pumilio (Poepp. & Endl.) Krasser in protected areas that are under invasion of exotic conifers.

Sobrevivência de espécies arbóreas plantadas em clareiras causadas pela colheita de madeira em uma floresta de terra firme no município de Paragominas na Amazônia brasileira / Survival of seedlings planted in gaps after harvesting in a terra firme rain forest in Paragominas region in the Brazilian Amazonia

Analisou-se a sobrevivência de mudas plantadas em 400 clareiras causadas por exploração florestal de impacto reduzido, em floresta de terra firme na Amazônia Oriental. Foram plantadas 3.818 mudas de 17 espécies, das quais apenas Schizolobium amazonicum não ocorre na área de estudo. A distância entre as mudas plantadas foi de aproximadamente 5m. As avaliações ocorreram em 2005 e 2006. Com base na sobrevivência das mudas aos 11 meses após o plantio, as espécies indicadas para o enriquecimento de clareiras são: Schizolobium amazonicum, Cedrela odorata, Jacaranda copaia, Manilkara huberi, Astronium gracile, Pouteria bilocularis, Tabebuia impetiginosa,Pseudopiptadenia suaveolens, Cordia goeldiana, Parkia gigantocarpa, Simarouba amara, Sterculia pilosa, Laetia procera, Dinizia excelsa e Schefflera morototoni. Estudos sobre a taxa de crescimento, em períodos mais longos, são necessários para confirmar a utilização dessas espécies em plantios de enriquecimento de clareiras oriundas de exploração florestal, como alternativa para aumentar a produtividade e o valor econômico das florestas naturais manejadas na Amazônia brasileira.

Survival of seedlings planted in 400 gaps created by reduced impact logging in a terra firme forest in the Eastern Amazonia was evaluated. 3,818 seedlings from 17 species occurring in the study area, except for Schizolobium amazonicum (paricá), which is rare in natural forests of Paragominas region, were planted in the gaps. Spacing of planted seedlings was 5m. According to survival of seedlings during 11 months after planting, the species Schizolobium amazonicum, Cedrela odorata, Jacaranda copaia, Manilkara huberi, Astronium gracile, Pouteria bilocularis, Tabebuia impetiginosa,Pseudopiptadenia suaveolens, Cordia goeldiana, Parkia gigantocarpa, Simarouba amara, Sterculia pilosa, Laetia procera, Dinizia excelsa and Schefflera morototoni can be suggested for enriching in gaps created by reduced impact logging. Complementary studies, mainly related to growth rates of seedlings, must be carried out and in a period longer than the present study to confirm the benefits of enrichment planting in gaps as an alternative to boost forest productivity and economic value of managed natural forest in the Brazilian Amazon.