Isolation of 27 polymorphic nuclear microsatellite markers for Roupala montana var. brasiliensis (Proteaceae).

Microsatellite primers pairs were developed for the Neotropical tree Roupala montana var. brasiliensis for use in studies on genetic diversity, mating system, and gene flow. Forty-two primer pairs were developed, resulting in 27 polymorphic loci, with two to 27 alleles per locus. The primer pairs were validated against 34 R. montana var. brasiliensis adult trees from four populations. The observed (H o) and expected (H e)heterozygosities ranged among loci from 0.061 to 0.930 (mean of 0.544) and from 0.116 to 0.950 (mean of 0.700), respectively. Null alleles were observed for ten loci. No genotypic linkage disequilibrium was detected in any pair of loci. This set of loci is suitable for population genetic studies of the species.

Fake legal logging in the Brazilian Amazon.

Declining deforestation rates in the Brazilian Amazon are touted as a conservation success, but illegal logging is a problem of similar scale. Recent regulatory efforts have improved detection of some forms of illegal logging but are vulnerable to more subtle methods that mask the origin of illegal timber. We analyzed discrepancies between estimated timber volumes of the national forest inventory of Brazil and volumes of logging permits as an indicator of potential fraud in the timber industry in the eastern Amazon. We found a strong overestimation bias of high-value timber species volumes in logging permits. Field assessments confirmed fraud for the most valuable species and complementary strategies to generate a "surplus" of licensed timber that can be used to legalize the timber coming from illegal logging. We advocate for changes to the logging control system to prevent overexploitation of Amazonian timber species and the widespread forest degradation associated with illegal logging.

Carbon recovery dynamics following disturbance by selective logging in Amazonian forests.

When 2 Mha of Amazonian forests are disturbed by selective logging each year, more than 90 Tg of carbon (C) is emitted to the atmosphere. Emissions are then counterbalanced by forest regrowth. With an original modelling approach, calibrated on a network of 133 permanent forest plots (175 ha total) across Amazonia, we link regional differences in climate, soil and initial biomass with survivors' and recruits' C fluxes to provide Amazon-wide predictions of post-logging C recovery. We show that net aboveground C recovery over 10 years is higher in the Guiana Shield and in the west (21 ±3 Mg C ha-1) than in the south (12 ±3 Mg C ha-1) where environmental stress is high (low rainfall, high seasonality). We highlight the key role of survivors in the forest regrowth and elaborate a comprehensive map of post-disturbance C recovery potential in Amazonia.

Rapid tree carbon stock recovery in managed Amazonian forests.

While around 20% of the Amazonian forest has been cleared for pastures and agriculture, one fourth of the remaining forest is dedicated to wood production. Most of these production forests have been or will be selectively harvested for commercial timber, but recent studies show that even soon after logging, harvested stands retain much of their tree-biomass carbon and biodiversity. Comparing species richness of various animal taxa among logged and unlogged forests across the tropics, Burivalova et al. found that despite some variability among taxa, biodiversity loss was generally explained by logging intensity (the number of trees extracted). Here, we use a network of 79 permanent sample plots (376 ha total) located at 10 sites across the Amazon Basin to assess the main drivers of time-to-recovery of post-logging tree carbon (Table S1). Recovery time is of direct relevance to policies governing management practices (i.e., allowable volumes cut and cutting cycle lengths), and indirectly to forest-based climate change mitigation interventions.

Efeito da exploração madeireira sobre o número de indivíduos férteis de três espécies arbóreas comerciais na Amazônia oriental / Effects of logging on the number of fertile individuals of three commercial tree species in Eastern Amazonia

Estudos da ecologia reprodutiva de árvores são fundamentais para compreender os possíveis impactos da exploração madeireira e para subsidiar o aperfeiçoamento das práticas de manejo. Os objetivos desse trabalho foram: 1) estimar a proporção e o número de indivíduos reprodutivos por classe de diâmetro de Chrysophyllum lucentifolium subsp. pachycarpum, Lecythis lurida e Pseudopiptadenia psilostachya, três espécies madeireiras, em uma floresta em Paragominas (PA) e; 2) estimar o impacto da exploração de 90 por cento dos indivíduos com DAP > 50 cm sobre o número de indivíduos reprodutivos das mesmas espécies no local. Durante uma estação reprodutiva de cada espécie, foram amostradas 80 árvores de L. lurida, 76 de P. psilostachya e 76 de C. lucentifolium. Foi estimado que 14,9 por cento de todos os indivíduos férteis de C. lucentifolium, 35,9 por cento de L. lurida e 72,4 por cento de P. psilostachya tinham DAP > 50 cm no ano de amostragem. Assim, o corte de 90 por cento dessas árvores causaria uma redução de 13,4 por cento, 32,6 por cento e 65,2 por cento do número de indivíduos férteis de C. lucentifolium, L. lurida e P. psilostachya, respectivamente. Se as proporções de indivíduos férteis fossem constantes ao longo do tempo, para preservar metade dos indivíduos férteis de P. psilostachya seria necessário manter 30 por cento e não 10 por cento daqueles com DAP > 50 cm. Os resultados indicam que, adotando-se um único diâmetro mínimo de corte e retendo-se a mesma proporção de árvores acima desse diâmetro, o efeito em termos de porcentagem de indivíduos reprodutivos retirados da população pode variar entre espécies na ordem de aproximadamente cinco vezes.

Studies concerning the reproductive ecology of trees are important so as to better understand the impacts of logging and for the definition of guidelines to improve management practices. The aim of this study was to estimate (1) the number and proportion of reproductive individuals of Chrysophyllum lucentifolium subsp. pachycarpum, Lecythis lurida e Pseudopiptadenia psilostachya per size class, and (2) the impact of harvesting 90 percent of individuals > 50 cm dbh on the number of reproductive trees. We sampled 80 L. lurida, 76 P. psilostachya and 76 C. lucentifolium trees during one reproductive season. We estimated that 14.9 percent of all fertile individuals of C. lucentifolium, 35.9 percent of L. lurida and 72.4 percent of P. psilostachya were > 50 cm dbh in that year. Therefore, the harvest of 90 percent of these trees would cause a 13.4 percent, 32.6 percent, and 65.2 percent reduction in the number of fertile individuals of C. lucentifolium, L. lurida and P. psilostachya, respectively. If these proportions were stable over time, it would be necessary to keep 30 percent instead of 10 percent of individuals > 50 cm dbh in order to preserve half of the P. psilostachya fertile individuals. The results indicate that the effects of adopting a single minimum cutting diameter and of setting aside the same proportion of trees above that diameter on the proportion of remaining fertile individuals may vary by a factor of five among species.

Beyond reaping the first harvest: management objectives for timber production in the Brazilian Amazon.

Millions of hectares of future timber concessions are slated to be implemented within large public forests under the forest law passed in 2006 by the Brazilian Congress. Additional millions of hectares of large, privately owned forests and smaller areas of community forests are certified as well managed by the Forest Stewardship Council, based on certification standards that will be reviewed in 2007. Forest size and ownership are two key factors that influence management objectives and the capacity of forest managers to achieve them. Current best ecological practices for timber production from Brazil's native Amazon forests are limited to reduced-impact logging (RIL) systems that minimize the environmental impacts of harvest operations and that obey legal restrictions regarding minimum diameters, rare species, retention of seed trees, maximum logging intensity, preservation of riparian buffers, fire protection, and wildlife conservation. Compared with conventional, predatory harvesting that constitutes >90% of the region's timber production, RIL dramatically reduces logging damage and helps maintain forest cover and the presence of rare tree species, but current RIL guidelines do not assure that the volume of timber removed can be sustained in future harvests. We believe it is counterproductive to expect smallholders to subscribe to additional harvest limitations beyond RIL, that larger private forested landholdings managed for timber production should be sustainable with respect to the total volume of timber harvested per unit area per cutting cycle, and that large public forests should sustain volume production of individual harvested species. These additional requirements would improve the ecological sustainability of forest management and help create a stable forest-based sector of the region's economy, but would involve costs associated with lengthened cutting cycles, reduced harvest intensities, and/or postharvest silviculture to promote adequate growth and regeneration.

O Pará no século XXI: oportunidades para o desenvolvimento sustentável / The State of Pará in twenty-first century: opportunities to sustainable development

Aborda questões críticas e emergentes sobre o uso da terra no Pará. Avalia a capacidade das instituições regionais em identificar e tratar essas questões. Analisa sete das principais formas de uso dos recursos naturais. Identifica necessidades que devem ser abordadas para apoiar cada uma dessas formas. Identifica áreas prioritárias para o trabalho futuro das instituições regionais do Pará. Analisa vinte e três instituições regionais, incluindo órgãos públicos e ONGs. Verifica que muitas das agências governamentais sofrem de falta de clareza em sua missão e de formas não-participativas de administração. Em contrapartida, muitas ONGs possuem uma missão bem definida e uma equipe profundamente motivada, porém atuam dentro de uma escala extremamente limitada. Explora as formas pelas quais as agências governamentais podem se tornar muito mais eficientes na definição e realização de suas missões e diminuir o impacto trágico do desmatamento na Amazônia Oriental.