Temporal Decay in Timber Species Composition and Value in Amazonian Logging Concessions

Wood volume is overestimated in the Brazilian Amazon: Why not use generic volume prediction methods in tropical forest management?

The Amazon has a range of species with high potential for sustainable timber harvesting, but for them to be utilized globally, the merchantable wood volume must be accurately quantified. However, since the 1950s, inadequate methods for estimating merchantable timber volumes have been employed in the Amazon, and Brazilian Government agencies still require some of them. The natural variability of the Amazon Forest provides an abundance of species of different sizes and shapes, conferring several peculiarities, which makes it necessary to use up-to-date and precise methods for timber quantification in Amazon Forest management. Given the employment of insufficient estimation methods for wood volume, this study scrutinizes the disparities between the actual harvested merchantable wood volume and the volume estimated by the forest inventory during the harvesting phase across five distinct public forest areas operating under sustainable forest management concessions. We used mixed-effect models to evaluate the relationships between inventory and harvested volume for genera and forest regions. We performed an equivalence test to assess the similarity between the volumes obtained during the pre-and post-harvest phases. We calculated root mean square error and percentage bias for merchantable volume as accuracy metrics. There was a strong tendency for the 100% forest inventory to overestimate merchantable wood volume, regardless of genus and managed area. There was a significant discrepancy between the volumes inventoried and harvested in different regions intended for sustainable forest management, in which only 22% of the groups evaluated were equivalent. The methods currently practiced by forest companies for determining pre-harvest merchantable volume are inaccurate enough to support sustainable forest management in the Amazon. They may even facilitate the region's illegal timber extraction and organized crime.

Current practices of conducting forest management plans in the Amazon may risk the survival of timber species

Measurement of the recovery of wood stocks in logging areas in the Amazon helps to understand the efficiency of policies for the use and conservation of native forests. This work evaluated the effects of logging on the dynamics and production of commercial species in the short and medium term in a conservation unit in the state of Rondônia. Structural patterns of the species as a function of mortality and recruitment rates, patterns of average increment in diameter, and estimates of forest production in the short and medium term were analyzed. The study was carried out in an area designated as Annual Production Unit 2 of Forest Management Unit III of Jamari National Forest. In addition to legalized harvesting, there are reports of illegal logging in the area as of 2015. Inventory data from 2011, 2015, and 2018 were used, considering trees of commercial value with a diameter at breast height (DBH) greater than 10 cm. Mortality rate, recruitment, periodic annual increment, absolute tree density, basal area, and commercial volume, by species and DBH classes, as well as the similarity of the species regarding the growth pattern. The population structure of species over the years was affected by tree mortality, mainly due to damage caused by illegal logging. Mean increment values varied by species and diameter classes, and six species represented 72% of the total volume of wood stock. It is important to review the criteria for sustainable forest production in the long term. Thus, it is necessary to promote species diversity and improve public authorities' capacity to enforce and of the private sector to comply with legislation. This, in turn, will enable the development of strategies to make the consumption of legal wood more rational.

Carbon payments can cost-effectively improve logging sustainability in the Amazon

Selective logging is pervasive across the tropics and unsustainable logging depletes forest biodiversity and carbon stocks. Improving the sustainability of logging will be crucial for meeting climate targets. Carbon-based payment for ecosystem service schemes, including REDD+, give economic value to standing forests and can protect them from degradation, but only if the revenue from carbon payments is greater than the opportunity cost of forgone or reduced logging. We currently lack understanding of whether carbon payments are feasible for protecting Amazonian forests from logging, despite the Amazon holding the largest unexploited timber reserves and an expanding logging sector. Using financial data and inventories of >660,000 trees covering 52,000 ha of Brazilian forest concessions, we estimate the carbon price required to protect forests from logging. We estimate that a carbon price of $7.90 per tCO₂ is sufficient to match the opportunity costs of all logging and fund protection of primary forest. Alternatively, improving the sustainability of logging operations by ensuring a greater proportion of trees are left uncut requires only slightly higher investments of $7.97-10.45 per tCO₂. These prices fall well below the current compliance market rate and demonstrate a cost-effective opportunity to safeguard large tracts of the Amazon rainforest from further degradation.

The Legal Roundwood Market in the Amazon and Its Impact on Deforestation in the Region between 2009–2015

Brazil is one of the largest producers of tropical wood in the world. Much of this wood is extracted from the Amazon region, especially in the state of Pará. Despite empirical knowledge, there is little information in the literature about the selectivity of trade and how this production has been behaving in recent years. Is there any relationship between this legal timber trade and deforestation? In this work, we compile data reports from control agencies and analyze the dynamics of the legal timber market in the state of Pará between 2009 and 2015 in terms of species, volume, and monetary value. We also correlate changes in volume m−3 and value m−3 with deforestation increase in the same period and region. We find that only ten groups of species represent almost 50% of the total timber volume marketed in the State, mainly from the Massaranduba (Manilkara) group. According to our models, the supply of a species of wood on the market is defined by its monetary value and not by its availability or characteristics, which hinders the insertion of new species and increases selectivity. Since 2011 the volume of legally traded logs has been decreasing sharply. Traditional forest regions in the state already demonstrate depletion in forested areas. While others, such as the lower Amazon region, have been increasing production, showing that new forestry operations areas are being used for harvesting in the function of the lower availability in traditional areas. Our models show that the legal reduced impact logging timber volume has an inverse relationship with the deforestation increase. Otherwise, preference for a small group of timber types still predominates, which may lead local woods to the danger of extinction.

The Effects of Environmental Changes on Plant Species and Forest Dependent Communities in the Amazon Region

We review the consequences of environmental changes caused by human activities on forest products and forest-dependent communities in the Amazon region—the vast Amazonas River basin and the Guiana Shield in South America. We used the 2018 and 2021 Intergovernmental Panel on Climate Change reports and recent scientific studies to present evidence and hypotheses for changes in the ecosystem productivity and geographical distribution of plants species. We have identified species associated with highly employed forest products exhibiting reducing populations, mainly linked with deforestation and selective logging. Changes in species composition along with a decline of valuable species have been observed in the eastern, central, and southern regions of the Brazilian Amazon, suggesting accelerated biodiversity loss. Over 1 billion native trees and palms are being lost every two years, causing economic losses estimated between US$1–17 billion. A decrease in native plant species can be abrupt and both temporary or persistent for over 20 years, leading to reduced economic opportunities for forest-dependent communities. Science and technology investments are considered promising in implementing agroforestry systems recovering deforested and degraded lands, which could engage companies that use forest products due to supply chain advantages.

Assessing assemblage-wide mammal responses to different types of habitat modification in Amazonian forests

Tropical forests are being heavily modified by varying intensities of land use ranging from structural degradation to complete conversion. While ecological responses of vertebrate assemblages to habitat modification are variable, such understanding is critical to appropriate conservation planning of anthropogenic landscapes. We assessed the responses of medium/large-bodied mammal assemblages to the ecological impacts of reduced impact logging, secondary regrowth, and eucalyptus and oil palm plantations in Eastern Brazilian Amazonia. We used within-landscape paired baseline-treatment comparisons to examine the impact of different types of habitat modification in relation to adjacent primary forest. We examined assemblage-wide metrics including the total number of species, number of primary forest species retained in modified habitats, abundance, species composition, and community integrity. We ranked all types of habitat modification along a gradient of assemblage-wide impact intensity, with oil palm and eucalyptus plantations exerting the greatest impact, followed by secondary regrowth, and selectively logging. Selectively-logged and secondary forests did not experience discernible biodiversity loss, except for the total number of primary forest species retained. Secondary forests further experienced pronounced species turnover, with loss of community integrity. Considering the biodiversity retention capacity of anthropogenic habitats, this study reinforces the landscape-scale importance of setting aside large preserved areas.

Primate conservation: Lessons learned in the last 20 years can guide future efforts

Twenty years ago, we published an assessment of the threats facing primates and with the passing of two decades, we re-evaluate identified threats, consider emerging pressures, identify exciting new avenues of research, and tackle how to change the system to rapidly advance primate and primate habitat conservation. Habitat destruction and hunting have increased, the danger of looming climate change is clearer, and there are emerging threats such as the sublethal effects of microplastics and pesticides. Despite these negative developments, protected areas are increasing, exciting new tools are now available, and the number of studies has grown exponentially. Many of the changes that need to occur to make rapid progress in primate conservation are in our purview to modify. We identify several dimensions indicating the time is right to make large advances; however, the question that remains is do we have the will to prevent widespread primate annihilation and extinction?

Contribution of Vouacapoua americana fruit-fall to the release of biomass in a lowland Amazon forest

Fruit-fall provides the transfer of biomass and nutrients between forest strata and remains a poorly understood component of Amazon forest systems. Here we detail fruit-fall patterns including those of Vouacapoua americana a Critically Endangered timber species across 25 km² of lowland Amazon forest in 2016. We use multi-model comparisons and an ensemble model to explain and interpolate fruit-fall data collected in 90 plots (totaling 4.42 ha). By comparing patterns in relation to observed and remotely sensed biomass estimates we establish the seasonal contribution of V. americana fruit-fall biomass. Overall fruit-fall biomass was 44.84 kg ha⁻¹ month⁻¹ from an average of 44.55 species per hectare, with V. americana dominating both the number and biomass of fallen fruits (43% and 64%, number and biomass respectively). Spatially explicit interpolations provided an estimate of 114 Mg dry biomass of V. americana fruit-fall across the 25 km² area. This quantity represents the rapid transfer by a single species of between 0.01 and 0.02% of the overall above ground standing biomass in the area. These findings support calls for a more detailed understanding of the contribution of individual species to carbon and nutrient flows in tropical forest systems needed to evaluate the impacts of population declines predicted from short (< 65 year) logging cycles.

Patterns of biodiversity response along a gradient of forest use in Eastern Amazonia, Brazil

The preservation of tropical forests is increasingly at risk, including forests located within human-modified landscapes that retain high conservation value. People modify and interact with these landscapes through a wide range of uses. However, our knowledge of how different forest uses affect biodiversity is limited. Here, we analyse the responses of different taxa to four distinct categories of forest management, namely old-growth forest, Brazil nut extraction areas, reduced impact logging areas, and eucalyptus plantations. Within six independent replicates of each category, we sampled three taxa (fruit-feeding butterflies, dung beetles, and trees) in eastern Amazonia. Forests under moderate use (Brazil nut extraction and reduced-impact logging) had similar, albeit slightly lower, diversity levels relative to old-growth forests, while communities in plantations were significantly less diverse. Only 4%, 20%, and 17%, of the sampled butterfly, dung beetle, and tree species, respectively, were restricted to old-growth forests. This study provides further empirical evidence of the importance of old-growth forest conservation in the context of human-modified landscapes. It also suggests that landscape matrices integrating forest uses at varying intensities are well positioned to reconcile biodiversity conservation with the production of goods that support local livelihoods.

Anthropogenic Disturbances Eroding the Genetic Diversity of a Threatened Palm Tree: A Multiscale Approach

Habitat loss and the illegal exploitation of natural resources are among the main drivers of species extinction around the world. These disturbances act at different scales, once changes in the landscape composition and configuration operate at large scales and exploitation of natural resources at local scales. Evidence suggests that both scales are capable of triggering genetic erosion in the remaining populations. However, most of the studies so far did not evaluate simultaneously the effects of these disturbances on genetic diversity and structure of plants. In this study, we used a multiple scale approach to empirically evaluate the impacts caused by local and landscape scale disturbances in the genetic diversity and structure of an endangered palm tree, Euterpe edulis. We sampled and genotyped with microsatellite markers 544 juveniles of E. edulis in 17 fragments of Atlantic Forest in Brazil. In addition, we estimated the local logging rate and the forest cover and isolation at landscape scale. We found that the palm populations have not undergone any recent bottleneck events and that only logging intensification had affected the fixation index and the number of private alleles. Additionally, we did not detect any evidence of spatial genetic structure or genetic divergence associated with environmental disturbance variables at different scales. However, we identified distinct genetic clusters, which may indicate a reduction of gene flow between fragments that were previously a continuous habitat. Our results show that local disturbances, which act directly on population size reduction, such as logging, modified the genetic diversity more rapidly, whereas genetic structure is probably more influenced by large-scale modifications. In this way, to maximize the conservation efforts of economically exploited species, we recommend to increase the inspection to reduce the illegal exploitation, and reforestation of degraded areas, in order to increase the gene flow in Atlantic Forest fragments.

Species distribution modeling reveals strongholds and potential reintroduction areas for the world's largest eagle

The highly interactive nature of predator-prey relationship is essential for ecosystem conservation; predators have been extirpated, however, from entire ecosystems all over the Earth. Reintroductions comprise a management technique to reverse this trend. Species Distribution Models (SDM) are preemptive tools for release-site selection, and can define levels of habitat quality over the species distribution. The Atlantic Forest of South America has lost most of its apex predators, and Harpy Eagles Harpia harpyja—Earth’s largest eagle—are now limited to few forest pockets in this domain. Harpy Eagles are supposedly widespread in the Amazon Forest, however, where habitat loss and degradation is advancing at a rapid pace. We aim to describe the suitability of threatened Amazonian landscapes for this eagle. We also aim to assess the suitability of remaining Atlantic Forest sites for Harpy Eagle reintroductions. Here we show that that considerable eagle habitat has already been lost in Amazonia due to the expansion of the “Arc of Deforestation”, and that Amazonian forests currently represent 93% of the current distribution of the species. We also show that the Serra do Mar protected areas in southeastern Brazil is the most promising region for Harpy Eagle reintroductions in the Atlantic Forest. Reintroduction and captive breeding programs have been undertaken for Harpy Eagles, building the technical and biological basis for a successful restoration framework. Our distribution range for this species represents a 41% reduction of what is currently proposed by IUCN. Furthermore, habitat loss in Amazonia, combined with industrial logging and hunting suggest that the conservation status of this species should be reassessed. We suggest researchers and conservation practitioners can use this work to help expand efforts to conserve Harpy Eagles and their natural habitats.

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.