Papers by Nataly Ascarrunz
Tropical Forest Issues
This article presents an analysis of aspects guiding the management of risks associated with wild... more This article presents an analysis of aspects guiding the management of risks associated with wildfires in territories governed by indigenous communities in Bolivia, and the crucial factors that contribute to responsive actions. These include: (i) indigenous worldviews regarding natural resources and the use of fire, (ii) strengthening of indigenous institutions for risk management, and (iii) autonomous, participatory and democratic indigenous community governance models. Using the Indigenous Territory of Lomerío of the Monkox nation as a case study, it also examines the advances, limitations and challenges in addressing wildfire threats, and the land management approach promoted by the indigenous territorial government.
Forests
A typical case of multiple-use forest management (MFM) in Southwestern Amazon is the commercial h... more A typical case of multiple-use forest management (MFM) in Southwestern Amazon is the commercial harvesting of Amazon or Brazil nut (Bertholletia excelsa) seeds and of timber of other tree species. Although the Amazon nut is the most important non-timber forest product (NTFP) in the Amazon basin, the species is under serious threat due to deforestation and may also be affected by overharvesting. However, selective logging of other tree species coexisting with Bertholletia may positively affect Bertholletia populations, thus enabling a special case for MFM. For this research, we investigated the impact of the intensity of Amazon nut harvesting and timber logging on Bertholletia populations in the Bolivian Amazon. We used demographic data from 72 two-hectare transects located within 24 community-based household forests varying in the intensity of nut collection (0–100%) and timber logging (0–15% of logging-disturbed forest area). Simulated Bertholletia population size increased with lo...
Tropical forest ecosystems are hotspots for biodiversity and represent one of the largest terrest... more Tropical forest ecosystems are hotspots for biodiversity and represent one of the largest terrestrial carbon stocks, making their role in climate change mitigation (CCM) programmes increasingly important (e.g. REDD+). In Latin America these ecosystems suffer from high land use pressures that have resulted in a dramatic biodiversity loss. Little is known about how CCM options may impact on biodiversity and how this in turn may affect ecosystem carbon storage. Within this context, the FP7 ROBIN (Role Of Biodiversity In climate change mitigatioN) project developed a framework for multi-scale integrated analysis of the impacts that land use change may have on the ecological and social-economic processes of these ecosystems. The framework represents a continuous feedback loop in which changes in CCM options modify land use, that results in biodiversity change, affecting ecosystem functions, leading to changes in ecosystem services that affect human outcomes and societal behaviour, and which then affect the main drivers and pressures on biodiversity and ecosystems, and so on. We have constructed an indicator framework that allows to quantify, link and assess these interactions at three spatial scales: regional (Central and South America), national (Bolivia, Brazil, Guyana and Mexico) and sub-national (study sites representing multifunctional landscapes). Indicators are selected through a demand-driven approach, by directing modelling and assessment efforts towards end-user relevant issues using stakeholder participatory processes. Indicator values are grounded on field data, statistics and model outputs. The framework provides a basis for understanding potential tipping points and unexpected consequences that may arise from the implementation of climate change mitigation policies, or management options (e.g. reducing deforestation and burning, or expansion of areas of biofuel crops in illegal areas). An illustrative example, showing how the framework helps to identify the appropriate indicators to synthesise the impacts of afforestation (one of the CCM options) across the ecological and socio-ecological processes and regions is presented. Index Terms-Biodiversity, climate change mitigation (CCM), framework for multi-scale integrated impact analysis, tropical forest ecosystems, social-ecological systems.
Cumulative carbon changes in TmFO plots
Model coefficients from Interactive effects of tree size, crown exposure and logging on drought-induced mortality
Mean coefficients for all models fit in this study across the entire dataset (i.e. that did not f... more Mean coefficients for all models fit in this study across the entire dataset (i.e. that did not fit separate models to logged and unlogged plots).
Annualized mortality rates for size and exposure classes of trees in logged and unlogged plots ac... more Annualized mortality rates for size and exposure classes of trees in logged and unlogged plots across a range of climatological moisture conditions.
all_mod_coefs from Interactive effects of tree size, crown exposure and logging on drought-induced mortality
Large trees in the tropics are reportedly more vulnerable to droughts than their smaller neighbou... more Large trees in the tropics are reportedly more vulnerable to droughts than their smaller neighbours. This pattern is of interest due to what it portends for forest structure, timber production, carbon sequestration and multiple other values given that intensified El Niño Southern Oscillation (ENSO) events are expected to increase the frequency and intensity of droughts in the Amazon region. What remains unclear is what characteristics of large trees renders them especially vulnerable to drought-induced mortality and how this vulnerability changes with forest degradation. Using a large-scale, long-term silvicultural experiment in a transitional Amazonian forest in Bolivia, we disentangle the effects of stem diameter, tree height, crown exposure and logging-induced degradation on risks of drought-induced mortality during the 2004/2005 ENSO event. Overall, tree mortality increased in response to drought in both logged and unlogged plots. Tree height was a much stronger predictor of mor...
Supplementary material from "Interactive effects of tree size, crown exposure and logging on drought-induced mortality
Large trees in the tropics are reportedly more vulnerable to droughts than their smaller neighbou... more Large trees in the tropics are reportedly more vulnerable to droughts than their smaller neighbours. This pattern is of interest due to what it portends for forest structure, timber production, carbon sequestration and multiple other values given that intensified El Niño Southern Oscillation (ENSO) events are expected to increase the frequency and intensity of droughts in the Amazon region. What remains unclear is what characteristics of large trees renders them especially vulnerable to drought-induced mortality and how this vulnerability changes with forest degradation. Using a large-scale, long-term silvicultural experiment in a transitional Amazonian forest in Bolivia, we disentangle the effects of stem diameter, tree height, crown exposure and logging-induced degradation on risks of drought-induced mortality during the 2004/2005 ENSO event. Overall, tree mortality increased in response to drought in both logged and unlogged plots. Tree height was a much stronger predictor of mor...
Finegan et al master matrix 62 plots
Data from: Does functional trait diversity predict aboveground biomass and productivity of tropical forests? Testing three alternative hypotheses
Metadata record for: The Forest Observation System, building a global reference dataset for remote sensing of forest biomass
This dataset contains key characteristics about the data described in the Data Descriptor The For... more This dataset contains key characteristics about the data described in the Data Descriptor The Forest Observation System, building a global reference dataset for remote sensing of forest biomass. <br> Contents: <br> 1. human readable metadata summary table in CSV format 2. machine readable metadata file in JSON format
Aim Tropical forests store 25% of global carbon and harbour 96% of the world’s tree species, but ... more Aim Tropical forests store 25% of global carbon and harbour 96% of the world’s tree species, but it is not clear whether this high biodiversity matters for carbon storage. Few studies have teased apart the relative importance of forest attributes and environmental drivers for ecosystem functioning, and no such study exists for the tropics.
Forests, 2021
A typical case of multiple-use forest management (MFM) in Southwestern Amazon is the commercial h... more A typical case of multiple-use forest management (MFM) in Southwestern Amazon is the commercial harvesting of Amazon or Brazil nut (Bertholletia excelsa) seeds and of timber of other tree species. Although the Amazon nut is the most important non-timber forest product (NTFP) in the Amazon basin, the species is under serious threat due to deforestation and may also be affected by overharvesting. However, selective logging of other tree species coexisting with Bertholletia may positively affect Bertholletia populations, thus enabling a special case for MFM. For this research, we investigated the impact of the intensity of Amazon nut harvesting and timber logging on Bertholletia populations in the Bolivian Amazon. We used demographic data from 72 two-hectare transects located within 24 community-based household forests varying in the intensity of nut collection (0–100%) and timber logging (0–15% of logging-disturbed forest area). Simulated Bertholletia population size increased with lo...
Tropical forest ecosystems are hotspots for biodiversity and represent one of the largest terrest... more Tropical forest ecosystems are hotspots for biodiversity and represent one of the largest terrestrial carbon stocks, making their role in climate change mitigation (CCM) programmes increasingly important (e.g. REDD+). In Latin America these ecosystems suffer from high land use pressures that have resulted in a dramatic biodiversity loss. Little is known about how CCM options may impact on biodiversity and how this in turn may affect ecosystem carbon storage. Within this context, the FP7 ROBIN (Role Of Biodiversity In climate change mitigatioN) project developed a framework for multi-scale integrated analysis of the impacts that land use change may have on the ecological and social-economic processes of these ecosystems. The framework represents a continuous feedback loop in which changes in CCM options modify land use, that results in biodiversity change, affecting ecosystem functions, leading to changes in ecosystem services that affect human outcomes and societal behaviour, and wh...
The Latin America Regional Nitrogen Centre: Concepts and Recent Activities
The activities related to the International Nitrogen Initiative (INI) Latin America Regional Cent... more The activities related to the International Nitrogen Initiative (INI) Latin America Regional Centre started in the early 2000s, in association with the international actions within the nitrogen (N) field. The office in Latin America was proposed in the context of broad global and local environmental changes and the agricultural need for nutrient addition, looking into processes that would horizontally permeate between these two important elements for human survival and for the Earth’s system. However, the lack of information on the nitrogen cycle in Latin America is a serious impediment to evaluate properly how human activity is altering nitrogen pools and turnover at regional and global scales. Empirical measurements of N deposition and other N cycle processes are extremely scarce in Latin America, and data feeding to global and regional circulation models lack spatial distribution information in this region.
Philosophical Transactions of the Royal Society B: Biological Sciences
Scientific Data
Forest biomass is an essential indicator for monitoring the Earth’s ecosystems and climate. It is... more 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 ...
Philosophical Transactions of the Royal Society B: Biological Sciences
Large trees in the tropics are reportedly more vulnerable to droughts than their smaller neighbou... more Large trees in the tropics are reportedly more vulnerable to droughts than their smaller neighbours. This pattern is of interest due to what it portends for forest structure, timber production, carbon sequestration and multiple other values given that intensified El Niño Southern Oscillation (ENSO) events are expected to increase the frequency and intensity of droughts in the Amazon region. What remains unclear is what characteristics of large trees render them especially vulnerable to drought-induced mortality and how this vulnerability changes with forest degradation. Using a large-scale, long-term silvicultural experiment in a transitional Amazonian forest in Bolivia, we disentangle the effects of stem diameter, tree height, crown exposure and logging-induced degradation on risks of drought-induced mortality during the 2004/2005 ENSO event. Overall, tree mortality increased in response to drought in both logged and unlogged plots. Tree height was a much stronger predictor of mort...
Environmental Research Letters
Around 30 Mm3 of sawlogs are extracted annually by selective logging of natural production forest... more Around 30 Mm3 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 20 m3 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 ar...
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Papers by Nataly Ascarrunz