Search

Na Amazônia brasileira, as florestas degradadas dominam as paisagens das frentes pioneiras. Atualmente, esta região enfrenta um grande desafio: parar a degradação e fazer a gestão sustentável dessas florestas. As florestas degradadas são atualmente parte integrante de uma categoria de florestas. No entanto, elas podem desempenhar um papel importante na luta contra as mudanças climáticas e podem contribuir para um melhor funcionamento ecológico dos territórios. Desenvolver políticas públicas com o duplo objetivo de reduzir a degradação e melhorar a condição dessas florestas implica um forte apoio da pesquisa. Neste Perspective, nós focalizamos em quatro prioridades de pesquisa: desenvolver os métodos de caracterização e monitoramento das florestas degradadas, elaborar planos específicos de ordenamento do território, compreender o papel desempenhado por todos os atores sociais e acompanhar as politicas em escala territorial. Made available in DSpace on 2017-06-15T13:11:14Z (GMT). No. of bitstreams: 1 Persp40LBLancPORT.pdf: 1714897 bytes, checksum: f24e82f477c6ace3166f21d716f525c5 (MD5) Previous issue date: 2017-06-14 Disponível também em inglês e francês.

Forest biomass is an essential indicator for monitoring the Earth’s ecosystems and climate. It is a critical input to greenhouse gas accounting, estimation of carbon losses and forest degradation, assessment of renewable energy potential, and for developing climate change mitigation policies such as REDD+, among others. Wall-to-wall mapping of aboveground biomass (AGB) is now possible with satellite remote sensing (RS). However, RS methods require extant, up-to-date, reliable, representative and comparable in situ data for calibration and validation. Here, we present the Forest Observation System (FOS) initiative, an international cooperation to establish and maintain a global in situ forest biomass database. AGB and canopy height estimates with their associated uncertainties are derived at a 0.25 ha scale from field measurements made in permanent research plots across the world’s forests. All plot estimates are geolocated and have a size that allows for direct comparison with many RS measurements. The FOS offers the potential to improve the accuracy of RS-based biomass products while developing new synergies between the RS and ground-based ecosystem research communities., Measurement(s)above-ground biomass • organic materialTechnology Type(s)tree species census • measurement methodFactor Type(s)geographic location • tree speciesSample Characteristic - Environmentforest biomeSample Characteristic - LocationEarth (planet) Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.9850571

Although tropical forests harbour most of the terrestrial carbon and biological diversity on Earth they continue to be deforested or degraded at high rates. In Amazonia, the largest tropical forest on Earth, a sixth of the remaining natural forests is formally dedicated to timber extraction through selective logging. Reconciling timber extraction with the provision of other ecosystem services (ES) remains a major challenge for forest managers and policy makers. This study applies a spatial optimisation of logging in Amazonian production forests to analyse potential trade-offs between timber extraction and recovery, carbon storage, and biodiversity conservation. Current logging regulations with unique cutting cycles result in sub-optimal ES-use efficiency. Long-term timber provision would require the adoption of a land-sharing strategy that involves extensive low-intensity logging, although high transport and road-building costs might make this approach economically unattractive. By contrast, retention of carbon and biodiversity would be enhanced by a land-sparing strategy restricting high-intensive logging to designated areas such as the outer fringes of the region. Depending on management goals and societal demands, either choice will substantially in uence the future of Amazonian forests. Overall, our results highlight the need for reevaluation of current logging regulations and regional cooperation among Amazonian countries to enhance coherent and trans-boundary forest management. Made available in DSpace on 2020-01-14T18:10:56Z (GMT). No. of bitstreams: 1 CPAFAP2019Optimalstrategiesofecosystemservices.pdf: 775227 bytes, checksum: 2c82d5c6280350cecac9770db875ae0a (MD5) Previous issue date: 2019 Na publicação consta: Lucas Mazzei.

Around 30Mm3 of sawlogs are extracted annually by selective logging of natural production forests in Amazonia, Earth?s most extensive tropical forest. Decisions concerning the management of these production forests will be of major importance for Amazonian forests? fate. To date, no regional assessment of selective logging sustainability supports decision-making. Based on data from 3500 ha of forest inventory plots, our modelling results show that the average periodic harvests of 20m3 ha?1 will not recover by the end of a standard 30 year cutting cycle. Timber recovery within a cutting cycle is enhanced by commercial acceptance of more species and with the adoption of longer cutting cycles and lower logging intensities. Recovery rates are faster in Western Amazonia than on the Guiana Shield. Our simulations suggest that regardless of cutting cycle duration and logging intensities, selectively logged forests are unlikely to meet timber demands over the long term as timber stocks are predicted to steadily decline. There is thus an urgent need to develop an integrated forest resource management policy that combines active management of production forests with the restoration of degraded and secondary forests for timber production. Without better management, reduced timber harvests and continued timber production declines are unavoidable. Made available in DSpace on 2019-11-14T18:23:27Z (GMT). No. of bitstreams: 1 CPAFAP2019CantimberprovisionfromAmazonian.pdf: 1180878 bytes, checksum: 1ac13277d4e677177e64186cd7c04ace (MD5) Previous issue date: 2019 Supplementary material for this article is available online.

In 2006, the Brazilian Forest Service (SFB) started an ambitious program to establish forest concessions so as to provide a legal framework for long-term sustainable timber production in Amazonian forests. Forest concessions in the Brazilian Amazon currently cover only 1.6 million ha (Mha) but we estimate the area of all potential concessions as 35 Mha. This paper assessed the conditions under which the present and potential concession system can ensure an annual production of 11 Mm3. yr−1 to meet the estimated present timber demand. For this we used the volume dynamics with differential equations model (VDDE) calibrated for the Amazon Basin with a Bayesian framework with data from 3500 ha of forest plots monitored for as long as 30 years after selective logging. Predictions of commercial volume recovery rates vary with location. We tested 27 different scenarios by using combinations of initial proportion of commercial volume, logging intensity and cutting cycle length. These scenarios were then applied to the current area of concessions and to the area of all potential concessions (35 Mha). Under current logging regulations and the current concession area (mean logging intensity of 15–20 m3.ha−1, a harvest cycle of 35 years and an initial commercial timber volume proportion of 20%), timber production can be maintained only for a single cutting cycle (35 years). Only the scenario with a logging intensity of 10 m3ha−1 every 60 years with a 90% initial proportion of commercial timber species can be considered as sustainable. Under this scenario, the maximum annual production with the present concession areas is 159,000 m3 (157–159), or less than 2% of the present annual production of 11 Mm3. When considering all potential concession areas (35 Mha), under current rules, the total annual production is 10 Mm3yr−1 (2–17 Mm3yr−1, 95% credibility interval) but is not maintained after the first logging cycle. Under the most sustainable scenario (see above) and a concession area of 35 Mha, the long-term sustainable annual production of timber reaches only 3.4 Mm3yr−1. Based on these results we argue that the concession system will not be able to supply the timber demand without substantial reforms in natural forest management practices and in the wood industry sector. We argue that alternative sources of timber, including plantations linked with forest restoration initiatives, must be promoted.

In the Brazilian Amazon, degraded forests dominate the landscapes on the agricultural frontiers. This region is now facing a major challenge: halting degradation and sustainably managing these forests. Today, degraded forests represent a class of forest in their own right. They can nevertheless play a key role in combating climate change, and can also help to improve the ecological functioning of the different territories. Implementing public policies with the twin objectives of reducing degradation and promoting these forests implies strong support from research. In this Perspective, we focus on four research priorities: developing methods to characterise and monitor degraded forests; drafting specific forest management plans; understanding the role played by all social actors; and supporting policies at the territorial level.

The prosecution of illegal logging crimes is hampered by a lack of available forensic timber identification tools, both for screening of suspect material and definitive identification of illegally sourced wood. Reputable timber traders are also struggling to police their own supply chains and comply with the growing requirement for due diligence with respect to timber origins and legality. A range of scientific methods have been developed independently with the potential to provide the required identification information, but little attention has been given to how these tools can be applied synergistically to support the legal timber trade. Here we review the use of visual identification methods (wood anatomy, dendrochronology), chemical methods (mass spectrometry, near infrared spectroscopy, stable isotopes, radio-carbon), and genetic methods (DNA barcoding, population genetics/phylogeography, DNA fingerprinting) each with potential application to forensic timber identification. We further highlight where future research and development are required to identify illegal logging crimes using these methods and suggest ways in which multiple methods can be used together to answer specific identification questions. We argue that a new integrated field of forensic timber identification should be a global investment priority, for which the ongoing collection, curation and taxonomic study of appropriate reference material is a critical part. Consideration of the specific legal requirements for method development and the application of identification methodologies to criminal evidence are also imperative to achieve robust scientific support for illegal logging crime prosecutions and prevention.

Background Genetic and epigenetic variations of the serotonin transporter gene (SLC6A4) have been related to the etiology of depression. The 5-HTTLPR polymorphism at the SLC6A4 promoter region has two variants, a short allele (S) and a long allele (L), in which the S allele results in lower gene transcription and has been associated with depression. The short S-allele of 5-HTTLPR polymorphism of this gene has been associated with depression. In addition to molecular mechanisms, exposure to early life risk factors such as maternal depression seems to affect the development of depression in postnatal life. The present study investigated the association of 5-HTTLPR polymorphism and CpG DNA methylation (5mC) levels of an AluJb repeat element at the SLC6A4 promoter region in mother–child pairs exposed to maternal depression. Methods We analyzed DNA samples from 60 subjects (30 mother–child pairs) split into three groups, with and without major depression disorder (DSM-IV) among children and mothers. The genotyping of 5-HTTLPR polymorphism and quantification of 5mC levels was performed by qualitative PCR and methylation-sensitive restriction enzyme digestion, and real-time quantitative PCR (MSRED-qPCR), respectively. Results The sample analyzed presented a higher frequency of S allele of 5-HTTLPR (67.5%). Despite the high frequency of this allele, we did not find statistically significant differences between individuals carrying at least one S allele between the depression and healthy control subjects, or among the mother–child pair groups with different patterns of occurrence of depression. In the group where the mother and child were both diagnosed with depression, we found a statistically significant decrease of the 5mC level at the SLC6A4 promoter region. Limitations The limitations are the relatively small sample size and lack of gene expression data available for comparison with methylation data. Conclusion In this study, we demonstrated a repeat element specific 5mC level reduction in mother–child pairs, concordant for the diagnosis of depression.

Selective logging in Brazil allows for the removal of up to 90% of trees above 50 cm diameter of a given timber species, independent of a species' life history characteristics or how quickly it will recover. The genetic and demographic effects of selective logging on two Amazonian timber species (Dipteryx odorata Leguminosae, Jacaranda copaia Bignoniaceae) with contrasting ecological and reproductive characteristics were assessed in the same forest. Genetic diversity and gene flow were characterized by genotyping adults and seed sampled before and after logging, using hypervariable microsatellite markers. Overall, there were no short-term genetic impacts on the J. copaia population, with commercial application of current Brazilian forest management regulations. In contrast, for D. Odorata, selective logging showed a range of genetic impacts, with a 10% loss of alleles, and reductions in siring by pollen from trees within the 546-ha study area (23-11%) and in the number of pollen donors per progeny array (2.8-1.6), illustrating the importance of the surrounding landscape. Asynchrony in flowering between D. odorata trees led to trees with no breeding partners, which could limit the species reproduction and regeneration under current regulations. The results are summarized with other published studies from the same site and the implications for forest management discussed. The different types and levels of impacts associated with each species support the idea that ecological and genetic information by species, ecological guild or reproductive group is essential in helping to derive sustainable logging guidelines for tropical forests.

Made available in DSpace on 2016-10-10T03:52:29Z (GMT). No. of bitstreams: 5 Genetic Structure Mating System and Long-Distance Gene Flow....pdf: 192228 bytes, checksum: 78f554358505c319f6574a9501eeba6e (MD5) license_url: 52 bytes, checksum: 2f32edb9c19a57e928372a33fd08dba5 (MD5) license_text: 24372 bytes, checksum: 94b0a37ff5ec51de8c55507bff4a7ff9 (MD5) license_rdf: 24623 bytes, checksum: 378d22d8fe50e084ee2f354be78cbe62 (MD5) license.txt: 1887 bytes, checksum: 445d1980f282ec865917de35a4c622f6 (MD5) Previous issue date: 2007 In this work, we report on the population genetic structure of the endangered tree species Manilkara huberi, an Amazonian tree species intensely exploited due to the high density and resistance of its wood. We investigated the patterns of spatial distribution, genetic structure, and mating system using 7 icrosatellite loci and here discuss the consequences for conservation and management of the species. To examine the population genetic structure, 481 adult trees and 810 seedlings were sampled from an area of 200 ha from a natural population in FLONA Tapajo´s, PA, Brazil. We found relatively high and consistent inbreeding levels (intrapopulation fixation index [f] 0.175 and 0.240) and a significant spatial genetic structure up to a radius of approximately 300 m, most likely due to a limited seed and pollen flow. The multilocus (tm) population outcrossing rate was high (0.995), suggesting that the species is predominantly allogamous with a pollen flow restricted to 47 m. These results suggest that M. huberi is spatially structured, consistent with a model of isolation by distance. Fragmentation may therefore cause the loss of subpopulations, suggesting that management programs for production and conservation should include large areas. The genetic data also revealed that for ex situ conservation, seeds should be collected from more than 175 maternal trees, in order to keep an effective population size of 500. Furthermore, as the species is widely distributed across the Amazon Forest, samples should include several populations in order to represent the highest genetic diversity possible. These results provide a blueprint to guide the production and conservation management policies of this valuable timber species. Sim Publicado

Using nine microsatellite loci, we studied the effects of selective logging on genetic diversity, mating system and pollen dispersal in a population of the tree species Hymenaea courbaril, located in a 546 ha plot in the Tapajos National Forest, Para State, Brazil. We analyzed 250 offspring (nursery reared seedlings) collected after a logging episode from 14 open-pollinated seed trees. These were compared to 367 seedlings from 20 open-pollinated seed trees previously collected from the pre-logging primary forest. The genetic diversity was significantly lower in the post-logging seed cohort. In contrast to the pre-logging population, significant levels of selfing were detected in the post-logging population (tm = 0.962, P

In this study, six highly polymorphic microsatellite loci and a categorical paternity analysis approach were used to investigate the contemporary pollen gene flow in the neotropical tree species Symphonia globulifera . Data for this study were taken from a 500 ha experimental plot in a dense terra firme forest in the Eastern Brazilian Amazon and included the mapping and genotyping of 161 reproductive trees, representing more than 90% of all adult trees, and the collection of 748 open-pollinated seeds from 56 seed-trees over two field seasons (2002 and 2003). High levels of pollen immigration from outside of the study plot were detected in both sampled seed-years (≥49%) suggesting long distance pollen gene flow. Low levels of self-fertilization were also detected (≤2%). The analysis showed long distance pollen dispersal occurred within the study area in both 2002 ( δ = 907 ± 652 m SD) and 2003 ( δ = 963 ± 542 m SD). Patterns of pollen dispersal distance within the plot were also found to be shorter than the distances between potential male parents and seed-trees. This result indicates that the distance between trees does not explain the identified pollen dispersal pattern. Our results support the hypothesis that animal pollinated species occurring in low-density populations can disperse pollen in long distances, despite the very dense nature of the forest.

SummaryWhile around 20% of the Amazonian forest has been cleared for pastures and agriculture, one fourth of the remaining forest is dedicated to wood production [1]. 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 [2,3]. Comparing species richness of various animal taxa among logged and unlogged forests across the tropics, Burivalova et al. [4] 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 [5] 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.

Jacaranda copaia (Aubl.) D. Don is a pioneer tree widespread in the Brazilian Amazon, usually found colonizing forest gaps and altered areas, and the forest fragment edges. This study investigated aspects of the floral biology, breeding system and pollinators of J. copaia trees. Flowering lasts from August to November, during the low rainfall period extending up to four weeks per tree and 3-4 months for the population as a whole, characterizing a cornucopia flowering pattern. The fruit set ends in the beginning of the rainy season, with wind dispersed winged seeds. Fruit set from open pollination was 1.06% (n = 6,932). Hand pollination using self-pollen (n = 2,099) did not set fruits. Cross-pollination resulted in 6.54% fruit set (n = 2,524), representing six times more than the natural pollination rate (1.06%, n = 6,932). Flowers excluded from insect visitation (automatic self-pollination) did not set fruits (n = 5,372). Pollen tube growth down to ovary was detected under fluorescence microcoscopy in cross-pollinated and selfed pistils. The species is an obligate allogamous plant, with late-acting self-incompatibility system. Approximately 40 species of native bees visited the flowers, but the main pollinators were medium-sized solitary bees as Euglossa and Centris species due to the compatibility between their body sizes with the corolla tube, direct contact with the reproductive structures and high frequency of visits. Jacaranda copaia (Aubl.) D. Don é uma árvore pioneira distribuída por toda Amazônia brasileira, encontrada colonizando clareiras, áreas alteradas e bordas de fragmentos florestais. O presente estudo investigou aspectos da biologia floral, sistema reprodutivo e polinizadores de J. copaia. O florescimento ocorre de agosto a novembro, durante o período de menor precipitação pluviométrica, estendendo-se por até quatro semanas por indivíduo e três ou quatro meses para a população, caracterizando um padrão de floração cornucopia. A frutificação termina no início da estação chuvosa, com a dispersão anemocórica das sementes aladas. A taxa de frutificação natural foi de 1,06% (n = 6.932). As flores autopolinizadas manualmente (n = 2.099) não produziram frutos. A polinização cruzada (n = 2.524) resultou em 6,54% frutos, representando seis vezes mais do que a polinização natural (1,06%, n = 6.932). As flores protegidas da visita de polinizadores (autopolinização espontânea) não formaram frutos (n = 5.372). O crescimento dos tubos polínicos foi detectado sob microscopia de fluorescência tanto nos pistilos autopolinizados quanto nos submetidos à polinização cruzada. A espécie foi considerada alógama obrigatória, com mecanismo de auto-incompatibilidade de ação tardia. Aproximadamente 40 espécies de abelhas nativas visitaram as flores, entretanto os polinizadores legítimos foram principalmente abelhas solitárias de médio porte dos gêneros Euglossa e Centris, em função da compatibilidade entre o tamanho corporal com o tubo da corola, que facilitava o contato direto com as estruturas reprodutivas, e a elevada freqüência de visitas.

O objetivo deste trabalho foi avaliar a existência de estruturação genética matrilinear em maçaranduba (Manilkara huberi). Foram avaliados 481 indivíduos adultos de M. huberi, distribuídos em 200 hectares de uma população natural na Floresta Nacional do Tapajós, Belterra, PA, e 88 regenerantes, com base na análise de nove microssatélites de cloroplasto e, de 96 indivíduos adultos, selecionados aleatoriamente na área de 200 ha, foi realizado o seqüenciamento de três regiões não codificadoras de cpDNA. Não foi detectado polimorfismo de seqüência. A análise da variabilidade haplotípica mostrou polimorfismo relativamente limitado, que resultou em 15 haplótipos, com diversidade genética total (hT) de 0,898. Foi detectada a existência de estruturação genética significativa em distâncias de até 250 m, o que indica dispersão de sementes restrita e confirma o padrão de organização espacial da variabilidade genética mostrado pela análise de DNA nuclear, o que evidencia isolamento por distância e a necessidade de manutenção de grandes áreas de floresta primária para garantir a sobrevivência de maior número de subpopulações.

Forest logging reduces population density and increases the distance between co-specifics and so can cause the loss of alleles, and affect the genetic diversity, spatial genetic structure (SGS), mating system, and pollen flow of the population. These factors were studied in the tropical tree species Bagassa guianensis Aubl. occurring in a low-density population in the Brazilian Amazon forest. Genetic diversity was compared among offspring, juveniles and adult trees, before and after selective logging. Non-significant differences were observed between these samples. The harvest of 61% of the adult trees caused the loss of three alleles in the reproductive population. However, these alleles were present in juveniles and offspring and so were not lost from the population. SGS was detected up to 300 m before logging in the overall and adult populations. After logging, significant SGS was not observed. Deviations from random matings were evident throughout biparental inbreeding ( 1 − t ˆ s = 0.067 , P r ˆ p ( m ) = 0.193 , P Φ ˆ ft = 0.081 , P

Levels of genetic diversity, inbreeding, and spatial genetic structure were investigated at different ontogenic stages for a population of Hymanaea courbaril , before and after Reduced Impact Logging (RIL) was applied, in a 546-ha plot in the Tapajos National Forest, in the Brazilian Amazon. The multilocus genotype of nine microsatellites loci was determined for 74 juveniles (dbh t -test, P > 0.05), they suggest the occurrence of inbreeding depression. All ontogenic stages showed spatial genetic structure at short distance classes ( t -test, P > 0.05). Logging also reduced the distance of the spatial genetic structure in the reproductive population from about 800 to 200 m. In general, our results indicate that RIL affected the gene pool and spatial genetic structure of the reproductive population.

Matingsystemandpollenflowaretwokeyelementstounderstandthegeneticstructureoftreespecies.Matingandpollen-dispersalpatternsofalow-densitypopulation of bat pollinated Hymanea courbaril were examined before logging in a 546-ha plot in the Brazilian Amazon. The multilocus genotypes of nine microsatellite loci were determined for 130 adult-trees and 367 seeds collected from 20 seed-trees. Mating system analysis, using mixed-mating model and paternity analysis showed that the studied population is perfectly outcrossed (tm = 1.002), and probably self-incompatible. However, significant deviations from random mating were detected for mating among relatives (tm − ts = 0.096, P 0.05). The effective number of pollen donors mating with each seed-tree was determined to be low (Nep ≈ 4). The average of pollen flow distance was measured inside of the plot by both paternity (827 ± 429 m) and TWOGENER analysis (115‐363 m). However, this underestimated pollen dispersal distance, since the detected rate of pollen immigration inside of the plot was high (55%). The observed long-pollen dispersal distance is probably related to pollination by bats and the low density of reproductive trees in the site.

In the last three decades, Amazon tropical forests have experienced high rates of deforestation, both by clearing for agriculture and by logging. In this study, we use computer simulations to examine the potential effects of forest logging on genetic diversity and demographic recovery (basal area development) of four neotropical tree species over a time frame reflecting multiple logging events. The study species, Bagassa guianensis Aubl., Hymenaea courbaril L., Manilkara huberi (Ducke) Chevalier, and Symphonia globulifera L.f., are all taxa which are commonly exploited for timber in the Brazilian Amazon. The simulations were parameterized using empirical data from field studies in the Tapajos National Forest, Para State, Brazil, including genotypes at microsatellite loci, demography, ecology and growth for each species. Eight scenarios, combining two different cutting cycles and two minimum cutting diameters, were examined for each of the four species. The scenarios represent the actual forest practices used in Brazil and French Guiana (cutting diameter 45 and 60 cm, and cutting cycle of 30 and 65 years, respectively). Logging scenarios were applied for six cutting cycles, and final genetic and demographic data were compared to baseline data from corresponding control scenarios. At the end of the simulated period the basal area was strongly reduced under all conditions in B. guianensis, H. courbaril, and M. huberi. In only two scenarios was a species able to recover its basal area following logging (S. globulifera with both 45- and 60-cm cutting diameters under a 65-year cutting cycle). In the logging scenarios, all species showed a loss of alleles and genotypes and an increased genetic distance (calculated between each population at the start and the end of the simulations). These effects were higher under the most intensive logging cycles (30 years, 45 cm). However, effective number of alleles, expected and observed heterozygosities, and the fixation index were little affected by the logging simulations. Over all, we conclude that, even under very optimistic conditions for growth and recruitment, current logging practices are not sustainable in terms of basal area. Our simulations show that different species respond differently to logging, both demographically and genetically. No single set of logging parameters can be applied to the forest as a whole. Rather, forest management practices must be species-specific, taking into account not only growth parameters but also ecological and reproductive variables, in order to move toward long-term forest sustainability.

Six microsatellite loci were used to compare the mating system and gene flow in two consecutive years of a natural, unlogged population of Symphonia globulifera in a 500 ha experimental plot in the Brazilian Amazon (Flona Tapaj6s). The species had a low density of reproductive trees per hectare (d = 0.46 trees/ha). We analyzed 205 trees and 261 and 487 open-pollinated seeds from 26 and 30 mother-trees in the years 2002 and 2003, respectively. A significant spatial genetic structure was detected for the adult trees for distances up to 100 m. We observed only small interannual differences in multilocus outcrossing rate (tim(2002) = 1.000, tm(2003) = 0.998), biparental inbreeding (Am - ts(2002) = 0.093, tm - ts(2003) = 0.063), and paternity correlation (rp(2002) = 0.414, ip(2003) = 0.386). The number of pollen donors contributing to mating of each tree in both years was estimated to be low (Siep = 2.4 - 4.0). Using TwOGENER analysis to calculate the density of reproductive trees and the distance of pollen dispersal for normal and exponential models, the lowest error was detected for exponential model. For this model, the estimated density of reproductive trees was lower in 2002 (ae(2002) = 0.03 trees/ha) than 2003 (de(2003) = 0.19 trees/ha), resulting in a higher distance of pollen dispersal in 2002 (3(2002) = 444 m) than 2003 (S(2003) = 154 m), although these changes did not affect the outcrossing and correlated mating rates.

The logging of large trees in tropical forests causes a decrease in the density of reproductive individ- uals, which likely affects the pattern of pollen dispersal and the mating system of the remaining trees in the pop- ulation. Here, we investigate the impact of logging on mating system and genetic diversity of the low-density, thrip-pollinated, dioecious tree Bagassa guianensis with- in a 500-ha plot at Tapajos National Forest, Para State, Brazil. Mating system parameters of the logged popula- tion were estimated using mixed-mating model. Six mi- crosatellite loci were used to genotype 232 seeds from ten remnant female trees over three seasons (2006, 2007, and 2008). The data were compared with the mating system of the unlogged population of B. guianensis (18 female trees, 488 seeds) in the same plot. The overall number of alleles found in the open-pollinated progenies decreased after logging (K=71 before logging and K=57 after logging, considering the three after logging seasons pooled), as well as the average number of alleles per locus (A = 11.8 and 9.5, respectively). Similarly, the number of private alleles, which is defined in the context of this study as the number of alleles observed in the population exclusively before or after logging, also de- creased after logging (15 and 1, respectively). However, the average number of alleles per locus and the observed and expected heterozygosities were not significantly higher before logging than after logging. Logging also did not affect the inbreeding of progenies in the popula- tion. Somewhat unexpectedly, the effective number of pollen donors was consistently higher after (Nep =1 4.5 in 2006, 8.1 in 2007, and 6.3 in 2008) than before log- ging (Nep = 3.4), suggesting that the loss of alleles in the population was compensated by the higher heterogeneity in the pollen pool after the removal of the largest trees by logging. Potential causes explaining the patterns found here include the maintenance of large patches of forest around the logged plot and the species' ability to perform long-distance pollination by airborne thrips. Maintenance of landscape integrity as logged and unlogged forests around the exploited areas is recom- mended to enhance pollen migration and to avoid long- term losses in genetic diversity.

While attention on logging in the tropics has been increasing, studies on the long-term effects of silviculture on forest dynamics and ecology remain scare and spatially limited. Indeed, most of our knowledge on tropical forests arises from studies carried out in undisturbed tropical forests. This bias is problematic given that logged and disturbed tropical forests are now covering a larger area than the so-called primary forests. A new network of permanent sample plots in logged forests, the Tropical managed Forests Observatory (TmFO), aims to fill this gap by providing unprecedented opportunities to examine long-term data on the resilience of logged tropical forests at regional and global scales. TmFO currently includes 24 experimental sites distributed across three tropical regions, with a total of 490 permanent plots and 921 ha of forest inventories.

Selective logging may impact patterns of genetic diversity within populations of harvested forest tree species by increasing distances separating conspecific trees, and modifying physical and biotic features of the forest habitat. We measured levels of gene diversity, inbreeding, pollen dispersal and spatial genetic structure (SGS) of an Amazonian insectpollinated Carapa guianensis population before and after commercial selective logging. Similar levels of gene diversity and allelic richness were found before and after logging in both the adult and the seed generations. Pre- and post-harvest outcrossing rates were high, and not significantly different from one another. We found no significant levels of biparental inbreeding either before or after logging. Low levels of pollen pool differentiation were found, and the pre- vs. post-harvest difference was not significant. Pollen dispersal distance estimates averaged between 75 m and 265 m before logging, and between 76 m and 268 m after logging, depending on the value of tree density and the dispersal model used. There were weak and similar levels of differentiation of allele frequencies in the adults and in the pollen pool, before and after logging occurred, as well as weak and similar pre- and post-harvest levels of SGS among adult trees. The large neighbourhood sizes estimated suggest high historical levels of gene flow. Overall our results indicate that there is no clear short-term genetic impact of selective logging on this population of C. guianensis .

The impact of logging and subsequent recovery after logging is predicted to vary depending on specific life history traits of the logged species. The Eco-gene simulation model was used to evaluate the long-term impacts of selective logging over 300 years on two contrasting Brazilian Amazon tree species, Dipteryx odorata and Jacaranda copaia. D. odorata (Leguminosae), a slow growing climax tree, occurs at very low densities, whereas J. copaia (Bignoniaceae) is a fast growing pioneer tree that occurs at high densities. Microsatellite multilocus genotypes of the pre-logging populations were used as data inputs for the Eco-gene model and post-logging genetic data was used to verify the output from the simulations. Overall, under current Brazilian forest management regulations, there were neither short nor long-term impacts on J. copaia. By contrast, D. odorata cannot be sustainably logged under current regulations, a sustainable scenario was achieved by increasing the minimum cutting diameter at breast height from 50 to 100 cm over 30-year logging cycles. Genetic parameters were only slightly affected by selective logging, with reductions in the numbers of alleles and single genotypes. In the short term, the loss of alleles seen in J. copaia simulations was the same as in real data, whereas fewer alleles were lost in D. odorata simulations than in the field. The different impacts and periods of recovery for each species support the idea that ecological and genetic information are essential at species, ecological guild or reproductive group levels to help derive sustainable management scenarios for tropical forests.

The effects of reduced-impact logging (RIL) on the regeneration of commercial tree species were investigated, as long-term timber yields depend partly on the availability of seedlings in a managed forest. On four occasions during a 20-month period in the TapajNational Forest (Eastern Amazon, Brazil), seven commercial tree species were assessed as follows: the long-lived pioneers Bagassa guianensis and Jacaranda copaia; the partially shade-tolerant Hymenaea courbaril, Dipteryx odorata, and Carapa guianensis; and the totally shade-tolerant Sympho- nia globulifera and Manilkara huberi. In 2439 10 9 10 m plots, all individuals < 20 cm diameter at breast height (dbh) were assessed over three intervals, before, during, and after the forest being logged. Before logging, the density of seedlings and saplings of the seven spe- cies did not change. Logged trees were spatially aggregated, with 9.2 percent of the plots being heavily impacted by logging. After log- ging, the recruitment rate increased more than the mortality rate, so that post-harvesting densities of seedlings and saplings increased. The increase in density was concentrated in logged plots with more disturbances. It is concluded that post-harvesting heterogeneity of micro-environments created by RIL may be an important component to be taken into account for sustainable forest management and conservation of commercial species.

This study evaluated the effect of nutrient application on the regrowth dynamics of secondary fallow vegetation in an intensely exploited shifting cultivation area in the eastern Amazon region of Brazil. The importance of N, P, K, Ca, Mg, S and a mixture of micronutrients was tested in a minus-one-trial by comparison with a full complement of nutrients and unfertilized control plots. Fertilizers were applied three times during the experiment and their effects were monitored over a period of 2 1/2 years. Prior to the second fertilization, one third of each experimental plot was cleared of the vegetation cover and planted in maize, prior to the third fertilizer application these subplots were planted in sorghum. Biomass of maize and sorghum were used to indicate nutrient constraints and fertilizing effects due to the different treatments. Both crops were limited by P- and N-availability, with greater responses to P. The initial fertilization did not affect the biomass accumulation of the secondary vegetation during the first 15 months, but two additional applications significantly increased biomass in the complete fertilizer treatment compared to the unfertilized control. Biomass accumulation was primarily P-limited, N-limitation was apparent but not significant. The remaining nutrients did not affect plant growth. Fertilization favored production of nutrient-rich leaves. Application of readily available nutrients gave grasses a competitive edge over slower reacting woody vegetation. Fertilization also caused significant shifts in the contribution of woody species to biomass accumulation, as could be demonstrated for two prominent pioneer tree species. Growth response to fertilization as well as the primary limiting nutrient varied among seven dominant species monitored in the secondary vegetation. We conclude that growth of tropical secondary vegetation can be nutrient limited and it might respond significantly to additional nutrients by increasing biomass production.

A comparative analysis of 23 populations of the Brazil nut tree ( Bertholletia excelsa ) across the Brazilian, Peruvian, and Bolivian Amazon shows that the history and intensity of Brazil nut exploitation are major determinants of population size structure. Populations subjected to persistent levels of harvest lack juvenile trees less than 60 centimeters in diameter at breast height; only populations with a history of either light or recent exploitation contain large numbers of juvenile trees. A harvesting model confirms that intensive exploitation levels over the past century are such that juvenile recruitment is insufficient to maintain populations over the long term. Without management, intensively harvested populations will succumb to a process of senescence and demographic collapse, threatening this cornerstone of the Amazonian extractive economy.

La conservation des ressources génétiques forestières garantit le maintien d'une diversité élevée, donc l'adaptation des espèces forestières tropicales aux conditions écologiques actuelles et futures. Elle nécessite d'élaborer des stratégies appropriées à l'aménagement des forêts et, pour cela, d'appréhender tout d'abord le niveau et la structure de la diversité génétique, de comprendre et prévoir ensuite sa dynamique. C'est dans cet esprit qu'une collaboration a été entreprise entre la Guyane française et le Brésil, malgré les différences existant entre les deux systèmes de gestion. À partir de résultats sur les parcelles expérimentales de Paracou (Guyane) et Tapajós (Brésil), un ensemble intégré d'outils a été élaboré, allant d'une base de données et d'utilitaires cartographiques jusqu'à un modèle de simulation de la dynamique des structures génétiques et à un logiciel de gestion.

Este artigo foca em aspectos indicadores de como a pesquisa agropecuária na Amazônia brasileira experimenta um momento de inflexão com tendência de intensificação na demanda de adoção de abordagens interdisciplinares e transdisciplinares, para que efetivamente contribuam ao alcance da sustentabilidade. Partindo de elementos indicadores da diversidade dos tipos de agricultura praticados na região, do histórico e da natureza da pesquisa agropecuária aí praticada, de conceitos inerentes aos tipos de pesquisa quanto ao seu caráter disciplinar, são comentadas estratégias de pesquisa necessárias para abordar um amplo conjunto de grandes temas prioritários e de políticas públicas voltadas ao atingimento da sustentabilidade em empreemdimentos agrícolas, finalizando com a identificação de desafios a enfrentar para ampliar e agilizar a adoção de práticas de pesquisa interdisciplinar e transdisciplinar na Amazônia. PALAVRAS-CHAVE: Amazônia. Ciências agrárias. interdisciplinar.

In the Brazilian Amazon, operators are required by law to follow sustainable forest management plans (SFMPs) that have been approved by the appropriate governmental institutions. As part of SFMPs, operators must conduct a 100% forest inventory of the area to be logged in a given year; they must also have annual operational plans that specify the activities to be carried out and indicate the trees to be logged, with their geographic position, scientific name, diameter at breast height, height, and wood volume. Harvesting is permitted only after state and federal agencies have evaluated and approved the annual operating plan. The forest inventories carried out to meet these legal requirements produce an enormous quantity of data, the analysis of which requires significant data-processing capacity. Most operators use electronic spreadsheets, making the process slow and cumbersome and not conducive to good forest management planning. Brazil’s forest sector needs—and demands—software that speeds up and improves the forest planning process by aiding the selection of harvest trees based on clear criteria, providing better control over timber production, and enabling sustainable forest management. Made available in DSpace on 2018-11-01T00:54:57Z (GMT). No. of bitstreams: 1 CPAFAP2018Bomanejosoftwareforforestmanagers.pdf: 251978 bytes, checksum: 41c6ea2e90d039fe7a7be244c4b18f4c (MD5) Previous issue date: 2018-10-26

Made available in DSpace on 2013-09-27T14:53:04Z (GMT). No. of bitstreams: 1 WOS000308817800014.pdf: 379718 bytes, checksum: a957238b7822bf2ada55c2c4a88d949f (MD5) Previous issue date: 2012-01-01 Made available in DSpace on 2013-09-30T19:24:50Z (GMT). No. of bitstreams: 1 WOS000308817800014.pdf: 379718 bytes, checksum: a957238b7822bf2ada55c2c4a88d949f (MD5) Previous issue date: 2012-01-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:34:50Z No. of bitstreams: 1 WOS000308817800014.pdf: 379718 bytes, checksum: a957238b7822bf2ada55c2c4a88d949f (MD5) Made available in DSpace on 2014-05-20T15:34:50Z (GMT). No. of bitstreams: 1 WOS000308817800014.pdf: 379718 bytes, checksum: a957238b7822bf2ada55c2c4a88d949f (MD5) Previous issue date: 2012-01-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) European Commission (SEEDSOURCE Project) Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) The Neotropical tree Hymenaea courbaril, locally known as Jatoba, is a valuable source of lumber and also produces comestible and medicinal fruit. We characterized Mendelian inheritance, linkage and genotypic disequilibrium at nine microsatellite loci isolated from H. courbaril, in order to determine if they would provide accurate estimates of population genetic parameters of this important Amazon species. The study was made on 250 open-pollinated offspring originated from 14 seed trees. Only one of nine loci presented significant deviation from the expected Mendelian segregation (1: 1). Genotypic disequilibrium between pairwise loci was investigated based on samples from 55 adult and 56 juvenile trees. No genetic linkage between any paired loci was observed. After Bonferroni's corrections for multiple tests, we found no evidence of genotypic disequilibrium between pairs of loci. We conclude that this set of loci can be used for genetic diversity/structure, mating system, gene flow, and parentage analyses in H. courbaril populations. Inst Florestal São Paulo, São Paulo, Brazil Inst Pesquisas Jardim Bot Rio de Janeiro, Inst Pesquisas, Rio de Janeiro, RJ, Brazil Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) Amazonia Oriental, Belem, Para, Brazil Univ Estadual São Paulo Julio de Mesquita Filho, Fac Engn Ilha Solteira, Ilha Solteira, SP, Brazil Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) Florestas, Curitiba, Parana, Brazil Inst Nacl de Pesquisas da Amazonia, Lab Genet & Biol Reprodut Plantas LARGEN, Manaus, Amazonas, Brazil Univ Estadual São Paulo Julio de Mesquita Filho, Fac Engn Ilha Solteira, Ilha Solteira, SP, Brazil European Commission (SEEDSOURCE Project): 003708 CNPq: 2006/04490-9

Made available in DSpace on 2018-05-31T00:43:40Z (GMT). No. of bitstreams: 1 SP19686ID31075.pdf: 446514 bytes, checksum: 5153833adf3f881608c2ad41756c8c5e (MD5) Previous issue date: 2009-02-26

Made available in DSpace on 2022-08-12T12:19:22Z (GMT). No. of bitstreams: 1 1-s2.0-S0378112707008808-main.pdf: 440136 bytes, checksum: e07110a2e651579ff15d1cf6df7f02fe (MD5) Previous issue date: 2008

Made available in DSpace on 2014-05-09T22:28:49Z (GMT). No. of bitstreams: 1 RIF4411681178.pdf: 14238237 bytes, checksum: 35a19f187cc98bbf620149115b1c9cab (MD5) Previous issue date: 1998-06-19 Anais do CONGRESSO NACIONAL SOBRE ESSÊNCIAS NATIVAS, 2., 1992, São Paulo.

Temporal and spatial genetic comparisons were made in an appalachian stand of Liriodendron tulipifera L. (tulip tree). The population was stratified into five age clsses, and allele frequencies were tested by homogeneity chi-square test within and among plots. The homogeneity in allee frequencies were also evaluated for plot and subplot differences, et different age levels. Results revealed that the population of tulip tree is structured in time and space: however, neither one was recognized as a result of the natural selection process. The lack of consistent patterns for differences in allele frequencies for age classes does not support evidence of selection. One possible constraint ay be the presence of rare alleles. Another explanation may be the presencebetween genetic and statistical sampling at different life cycle stages. The susbstructure in space in much stronger than in time significant differences in allele frequencies at different coli for plts within age classes suggest that the population in substructure at the subplot level. The substructure is more likely to be associated with the epecies'reproductive biological characteristics such as mixed mating systems, and/or limited gene flow. Made available in DSpace on 2022-10-18T14:08:20Z (GMT). No. of bitstreams: 1 The-demographic-genetic-of-an-appalachian.pdf: 14444095 bytes, checksum: 74949e46e927ab19fd4bec01393977e8 (MD5) Previous issue date: 1990 Ph.D. Thesis.

Made available in DSpace on 2019-07-04T00:59:33Z (GMT). No. of bitstreams: 1 Pesquisasflorestais.pdf: 2017449 bytes, checksum: 7aa247db705c2333f950be18288e9c5c (MD5) Previous issue date: 1983 Anais do 4º Congresso Florestal Brasileiro, 1982, Belo Horizonte.

Made available in DSpace on 2019-07-06T01:03:01Z (GMT). No. of bitstreams: 1 Propagacaovegetativa.pdf: 811919 bytes, checksum: f4789d1d772a4d0cc34bd68e36d2e4ae (MD5) Previous issue date: 1983 Anais do 4º Congresso Florestal Brasileiro, 1982, Belo Horizonte.

Made available in DSpace on 2019-07-06T01:03:57Z (GMT). No. of bitstreams: 1 Informacoessobrecordia.pdf: 3038968 bytes, checksum: a7102818b336870fbf2258cd607ae9d9 (MD5) Previous issue date: 1983 Anais do 4º Congresso Florestal Brasileiro, 1982, Belo Horizonte.

The production of genetically improved seed of Eucalyptus spp requires more detailed research on the nursery practices in order to avoid seed losses. Eucalyptus urophylla and Eucalyptus grandis seeds were processed by hand and by a gravity separator to get the desired separation of light and small seeds from those heavy and large. Each fraction obtained from the separation by hand and by the gravity separator was utilized in the pellenization process. The celofaz and the hiperfosfate were eficient respectivelly as adesive and as inert material. Separation by gravity reduced the number of pellets without seed due to the increase of the purity. Fraction medium and heavy were not significant and the utilization of both can be done. The pellets formed with the smallest seeds (fraction light and small ) were worse than those heavy and medium. Germination rate decreased with the icrease of the pellet size probably due to the barrier developted by the pelletization, showing the existance of a limit to the pellet size.

Made available in DSpace on 2021-04-14T17:34:01Z (GMT). No. of bitstreams: 1 Programa-de-melhoramento-genetico.pdf: 1553727 bytes, checksum: 5a8984ddc1fb4d1552a9c721117d7d20 (MD5) Previous issue date: 1983