cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.20004983
title: Wood and bark water content and monthly stem growth in Amazonian tree species

description: ABSTRACT The knowledge of how trees respond to microclimate variability is important in the face of climate changes. The objectives of this study were to examine the variation in wood water content (WWC) and bark water content (BWC) in Amazonian trees, as well as to assess the effect of microclimatic variability on monthly diameter growth rates (DGR). We extracted a core sample from each of 120 trees (28 species) and determined WWC and BWC on a fresh matter basis. DGR was measured monthly during the 12 months of 2007. The effect of microclimatic variability on DGR was analyzed by redundancy analysis. Average BWC and WWC were 53.4% and 34.7%, respectively, with a large variation in stem water content among species (BWC = 36.2−67.1%; WWC = 26.4−50.8%). There was no significant relationship between stem diameter and WWC or BWC, nor between DGR and wood density (p &gt; 0.05). However, wood density was negatively correlated with WWC (r s = −0.69, p &lt; 0.001). The high BWC emphasizes the importance of the bark tissue in Amazonian trees. Contrary to expectations, variability of monthly irradiance, rainfall and temperature had no effect on DGR (p &gt; 0.20). The unresponsiveness of DGR to microclimatic variability, even in an above-average rainy year such as 2007, indicates that other parts of the tree may have greater priority than the stem for carbon allocation during the dry season.
DOI: 10.6084/m9.figshare.20004983.v1
title: Wood and bark water content and monthly stem growth in Amazonian tree species

description: ABSTRACT The knowledge of how trees respond to microclimate variability is important in the face of climate changes. The objectives of this study were to examine the variation in wood water content (WWC) and bark water content (BWC) in Amazonian trees, as well as to assess the effect of microclimatic variability on monthly diameter growth rates (DGR). We extracted a core sample from each of 120 trees (28 species) and determined WWC and BWC on a fresh matter basis. DGR was measured monthly during the 12 months of 2007. The effect of microclimatic variability on DGR was analyzed by redundancy analysis. Average BWC and WWC were 53.4% and 34.7%, respectively, with a large variation in stem water content among species (BWC = 36.2−67.1%; WWC = 26.4−50.8%). There was no significant relationship between stem diameter and WWC or BWC, nor between DGR and wood density (p &gt; 0.05). However, wood density was negatively correlated with WWC (r s = −0.69, p &lt; 0.001). The high BWC emphasizes the importance of the bark tissue in Amazonian trees. Contrary to expectations, variability of monthly irradiance, rainfall and temperature had no effect on DGR (p &gt; 0.20). The unresponsiveness of DGR to microclimatic variability, even in an above-average rainy year such as 2007, indicates that other parts of the tree may have greater priority than the stem for carbon allocation during the dry season.
DOI: 10.6084/m9.figshare.20004984
title: Assessment of fire hazard weather indices in the eastern Amazon: a case study for different land uses

description: ABSTRACT The fire frequency in the Amazon increased rapidly after the 1990s due to deforestation and forest degradation, and it is expected to increase in response to climate change. We analyzed the fire occurrence and assessed seven fire hazard indices in the municipality of Canaã dos Carajás, in the eastern Amazon, for different land use and land cover (LULC) types. We used data from three weather stations located at different heights to compare the performance of the indices using skill scores and success percentages for each LULC. Overall most hotspots occurred in deforested areas and native forests, which were the main LULC types, while few were observed in rupestrian fields, urban areas, and mining areas. However, forests presented the lowest number of hotspots per unit area, especially inside protected areas, and all hotspots in forest areas were observed after a severe drought in 2015. The performance of the fire indices varied as a function of the LULC class and the weather station considered, which indicates the importance of choosing the most appropriate location of the station according to the purpose of the monitoring. The Keetch-Byram Drought Index showed the best performance for predicting fire occurrence for all LULC classes, and forests and deforested areas individually. Despite its simplicity, the Angstrom index stood out due to its good performance in the prediction of days with more than six hotspots.
DOI: 10.6084/m9.figshare.20004984.v1
title: Assessment of fire hazard weather indices in the eastern Amazon: a case study for different land uses

description: ABSTRACT The fire frequency in the Amazon increased rapidly after the 1990s due to deforestation and forest degradation, and it is expected to increase in response to climate change. We analyzed the fire occurrence and assessed seven fire hazard indices in the municipality of Canaã dos Carajás, in the eastern Amazon, for different land use and land cover (LULC) types. We used data from three weather stations located at different heights to compare the performance of the indices using skill scores and success percentages for each LULC. Overall most hotspots occurred in deforested areas and native forests, which were the main LULC types, while few were observed in rupestrian fields, urban areas, and mining areas. However, forests presented the lowest number of hotspots per unit area, especially inside protected areas, and all hotspots in forest areas were observed after a severe drought in 2015. The performance of the fire indices varied as a function of the LULC class and the weather station considered, which indicates the importance of choosing the most appropriate location of the station according to the purpose of the monitoring. The Keetch-Byram Drought Index showed the best performance for predicting fire occurrence for all LULC classes, and forests and deforested areas individually. Despite its simplicity, the Angstrom index stood out due to its good performance in the prediction of days with more than six hotspots.
DOI: 10.6084/m9.figshare.20004987
title: Behind the forest restoration scene: a socio-economic, technical-scientific and political snapshot in Amazonas, Brazil

description: ABSTRACT Conservation of the Amazon rainforest is a global concern and is supported by the Brazilian government’s ratification of the Bonn Challenge and Paris Agreement and the introduction of national regulations on vegetation protection and restoration. Amazonas is the largest and least deforested of the states occupied by the Brazilian Amazon (&lt; 3%). We carried out a survey on the current state and growth potential of seed and seedling production in Amazonas state, pointing out constraints where future investment can promote the achievement of large-scale restoration commitments. We visited the 35 officially registered seed producers or nurseries working with native seeds and interviewed their owners or managers using open and closed questions. Enterprises were mainly privately-owned family businesses with small production (10,001 - 100,000 seedlings per year) and concentrated in the metropolitan area of the state capital Manaus. We uncovered a further 54 non-officially registered nurseries. Annual production (2018) was almost four tons of seeds and nearly ten million seedlings. According to the owners, production could be increased five to seven times with existing infrastructure. Production is focused foremost on species for food production (48% seeds, 74% seedlings), while ecological restoration only makes up 35% of seed and 8% of seedling use. Major bottlenecks cited by the producers were low demand for native tree species, high transportation costs and excessive bureaucracy. To achieve large-scale restoration, we recommend enforcement of national policies for vegetation protection and restoration, and a restructuring of the seed and seedling sector with a bottom-up approach.
DOI: 10.6084/m9.figshare.20004987.v1
title: Behind the forest restoration scene: a socio-economic, technical-scientific and political snapshot in Amazonas, Brazil

description: ABSTRACT Conservation of the Amazon rainforest is a global concern and is supported by the Brazilian government’s ratification of the Bonn Challenge and Paris Agreement and the introduction of national regulations on vegetation protection and restoration. Amazonas is the largest and least deforested of the states occupied by the Brazilian Amazon (&lt; 3%). We carried out a survey on the current state and growth potential of seed and seedling production in Amazonas state, pointing out constraints where future investment can promote the achievement of large-scale restoration commitments. We visited the 35 officially registered seed producers or nurseries working with native seeds and interviewed their owners or managers using open and closed questions. Enterprises were mainly privately-owned family businesses with small production (10,001 - 100,000 seedlings per year) and concentrated in the metropolitan area of the state capital Manaus. We uncovered a further 54 non-officially registered nurseries. Annual production (2018) was almost four tons of seeds and nearly ten million seedlings. According to the owners, production could be increased five to seven times with existing infrastructure. Production is focused foremost on species for food production (48% seeds, 74% seedlings), while ecological restoration only makes up 35% of seed and 8% of seedling use. Major bottlenecks cited by the producers were low demand for native tree species, high transportation costs and excessive bureaucracy. To achieve large-scale restoration, we recommend enforcement of national policies for vegetation protection and restoration, and a restructuring of the seed and seedling sector with a bottom-up approach.
DOI: 10.6084/m9.figshare.20004989
title: Land use dynamics under the Bolsa Floresta Program: a case study of the Uatumã Sustainable Development Reserve (Amazonas, Brazil)

description: ABSTRACT The effectiveness of a program of payment for environmental services (PES) in the Brazilian Amazon was analyzed through an accurate mapping of deforested areas. The Bolsa Floresta Program (BFP) in Amazonas state (Brazil) was chosen as an example of a PES program that aims to compensate farmers for their commitment to zero deforestation of primary forests while opening swiddens only in secondary vegetation areas. However, the official measurement of opened swiddens is not effective since only deforested areas larger than 6.25 ha are mapped, whereas most areas opened for cassava crops are approximately 1 ha in size. The effectiveness of the BFP was evaluated in the Uatumã Sustainable Development Reserve (SDR). We tested a methodology for mapping areas from 0.45 ha upwards that have been opened for cassava swiddens. The years 2006 (before the implementation of the BFP), 2011, 2015 and 2019 were analyzed. The results indicated that 88% of the areas opened for swiddens were between 0.45 and 6.25 ha in size. After the implantation of the BFP, the cumulative total deforested area decreased, and there was a reduction in deforested areas in primary forests. An intensification of swidden cultivation was also observed, which could cause a decline in productivity. The monitoring by land-use zoning showed that the majority of opened areas were located in intensive use zones, following the rules of the SDR management plan. The results show the efforts of local families to fulfill the BFP rules.
DOI: 10.6084/m9.figshare.20004989.v1
title: Land use dynamics under the Bolsa Floresta Program: a case study of the Uatumã Sustainable Development Reserve (Amazonas, Brazil)

description: ABSTRACT The effectiveness of a program of payment for environmental services (PES) in the Brazilian Amazon was analyzed through an accurate mapping of deforested areas. The Bolsa Floresta Program (BFP) in Amazonas state (Brazil) was chosen as an example of a PES program that aims to compensate farmers for their commitment to zero deforestation of primary forests while opening swiddens only in secondary vegetation areas. However, the official measurement of opened swiddens is not effective since only deforested areas larger than 6.25 ha are mapped, whereas most areas opened for cassava crops are approximately 1 ha in size. The effectiveness of the BFP was evaluated in the Uatumã Sustainable Development Reserve (SDR). We tested a methodology for mapping areas from 0.45 ha upwards that have been opened for cassava swiddens. The years 2006 (before the implementation of the BFP), 2011, 2015 and 2019 were analyzed. The results indicated that 88% of the areas opened for swiddens were between 0.45 and 6.25 ha in size. After the implantation of the BFP, the cumulative total deforested area decreased, and there was a reduction in deforested areas in primary forests. An intensification of swidden cultivation was also observed, which could cause a decline in productivity. The monitoring by land-use zoning showed that the majority of opened areas were located in intensive use zones, following the rules of the SDR management plan. The results show the efforts of local families to fulfill the BFP rules.
DOI: 10.26302/sshade/experiment_cc_20180427_001
title: VNIR reflectance spectra of Thenardite with 3 different grain sizes and at variable temperature (93-279 K)

description: Vis-NIR (0.8-4.2 µm) reflectance spectra of Thenardite with three different grain sizes (36-50, 75-100 and 125-150 µm) acquired at 11 temperatures between 93K and 279K
DOI: 10.6084/m9.figshare.20004995.v1
title: Innate immunity gene expression profiles in conjunctival membrane biopsies from Amazonian buffalo

description: ABSTRACT Domestic buffalo production plays an economically important role in the Brazilian Amazon, but they are susceptible to many diseases favored by the tropical climate and annually flooded habitats, including ocular diseases. In this context, it is important to select genotypes that maximize innate ocular immunity in Amazonian herds. We aimed to characterise, for the first time, gene expression profiles of the innate immune system in the conjunctival membrane of buffalo. Ocular conjunctival tissue samples were collected from 60 clinically healthy slaughtered animals in the northern Brazilian state of Amapá. The samples were histologically processed for classification into three groups according to the quantitative degree of lymphoid tissue associated with the conjunctiva (discrete, G1; slight, G2; and moderate, G3 presence of lymphoid tissue). RT-PCR was used to quantify gene expression of inflammatory cytokine (IL6, IL10, TNFA, IFNG), Toll-like receptor 4 (TLR4), and Defensin beta 110 (DEFB110), relative to the endogenous GAPDH gene. G1 animals presented low expression for IL6, IL10, TNFA, and DEFB110, while G2 exhibited high expression for IL6, IL10, IFNG, and TLR4. All G3 animals showed high expression for all tested genes. These results suggest a greater resistance to pathogenic microorganisms of buffalos in the G3 group, and the proportion of lymphoid tissue associated with the conjunctiva may be related to the immune resistance of individuals.
DOI: 10.6084/m9.figshare.20004995
title: Innate immunity gene expression profiles in conjunctival membrane biopsies from Amazonian buffalo

description: ABSTRACT Domestic buffalo production plays an economically important role in the Brazilian Amazon, but they are susceptible to many diseases favored by the tropical climate and annually flooded habitats, including ocular diseases. In this context, it is important to select genotypes that maximize innate ocular immunity in Amazonian herds. We aimed to characterise, for the first time, gene expression profiles of the innate immune system in the conjunctival membrane of buffalo. Ocular conjunctival tissue samples were collected from 60 clinically healthy slaughtered animals in the northern Brazilian state of Amapá. The samples were histologically processed for classification into three groups according to the quantitative degree of lymphoid tissue associated with the conjunctiva (discrete, G1; slight, G2; and moderate, G3 presence of lymphoid tissue). RT-PCR was used to quantify gene expression of inflammatory cytokine (IL6, IL10, TNFA, IFNG), Toll-like receptor 4 (TLR4), and Defensin beta 110 (DEFB110), relative to the endogenous GAPDH gene. G1 animals presented low expression for IL6, IL10, TNFA, and DEFB110, while G2 exhibited high expression for IL6, IL10, IFNG, and TLR4. All G3 animals showed high expression for all tested genes. These results suggest a greater resistance to pathogenic microorganisms of buffalos in the G3 group, and the proportion of lymphoid tissue associated with the conjunctiva may be related to the immune resistance of individuals.
DOI: 10.6084/m9.figshare.20004996
title: Effects of fire on soil organic matter in northern Amazonian forest fragments

description: ABSTRACT Forest fires incorporate pyrogenic organic matter into the soil, affecting the characteristics of soil organic matter (SOM) due to its high aromaticity, increasing its renewal time. However, the factors that control the concentration of pyrogenic organic matter and its chemical composition and structure are still little known. Forest fragments dispersed in a savanna matrix of the northern Brazilian Amazon are frequently impacted by fires, which can affect the composition of SOM within the fragments. The aim of this study was to analyse the chemical composition of SOM in the border and interior of six forest fragments in the Roraima savanna, in the northern Brazilian Amazon. Soil samples were collected at 10-cm intervals up to 1 m in depth at the border and in the interior of each fragment. Soil organic material concentration was determined with 10% HF solution and its elemental composition, thermogravimetric index, and 13C CPMAS NMR spectroscopic analysis were determined. There was no significant difference in the aromaticity index between border and interior. The concentration of alkyl C structures between border (22 to 25%) and interior (19 to 29%) indicated the occurrence of medium-intensity fires in the study area. The thermogravimetric analysis showed no significant difference in the thermal stability of SOM between border and interior. Our results showed no pronounced difference in SOM quality up to 1 m depth between the border and the interior of the evaluated forest fragments, indicating that this compartment is stable throughout the fragments.
DOI: 10.6084/m9.figshare.20004996.v1
title: Effects of fire on soil organic matter in northern Amazonian forest fragments

description: ABSTRACT Forest fires incorporate pyrogenic organic matter into the soil, affecting the characteristics of soil organic matter (SOM) due to its high aromaticity, increasing its renewal time. However, the factors that control the concentration of pyrogenic organic matter and its chemical composition and structure are still little known. Forest fragments dispersed in a savanna matrix of the northern Brazilian Amazon are frequently impacted by fires, which can affect the composition of SOM within the fragments. The aim of this study was to analyse the chemical composition of SOM in the border and interior of six forest fragments in the Roraima savanna, in the northern Brazilian Amazon. Soil samples were collected at 10-cm intervals up to 1 m in depth at the border and in the interior of each fragment. Soil organic material concentration was determined with 10% HF solution and its elemental composition, thermogravimetric index, and 13C CPMAS NMR spectroscopic analysis were determined. There was no significant difference in the aromaticity index between border and interior. The concentration of alkyl C structures between border (22 to 25%) and interior (19 to 29%) indicated the occurrence of medium-intensity fires in the study area. The thermogravimetric analysis showed no significant difference in the thermal stability of SOM between border and interior. Our results showed no pronounced difference in SOM quality up to 1 m depth between the border and the interior of the evaluated forest fragments, indicating that this compartment is stable throughout the fragments.
DOI: 10.6084/m9.figshare.20005002
title: First evidence of frugivory in Gardnerycteris crenulatum (Chiroptera: Phyllostomidae)

description: ABSTRACT Gardnerycteris crenulatum is a bat species restricted to South America, being particularly rare in lowland rainforests. It is characterized by a diet composed mainly of arthropods and small vertebrates, with no confirmed evidence of fruit consumption. Here, we provide the first records of seeds in the diet of G. crenulatum. The seeds were found in the feces of two individuals captured in late-successional forests in the Colombian Amazon (one pregnant female and one adult male), that belonged to Piper sp. (n = 125) and Cecropia engleriana (n = 3). In germination experiments, only Piper seeds germinated (8%). Insectivores can potentially perform other functions than the role assigned to their corresponding guild. More research is needed on the natural history and ecology of G. crenulatum to elucidate its possible role as seed disperser.
DOI: 10.6084/m9.figshare.20005002.v1
title: First evidence of frugivory in Gardnerycteris crenulatum (Chiroptera: Phyllostomidae)

description: ABSTRACT Gardnerycteris crenulatum is a bat species restricted to South America, being particularly rare in lowland rainforests. It is characterized by a diet composed mainly of arthropods and small vertebrates, with no confirmed evidence of fruit consumption. Here, we provide the first records of seeds in the diet of G. crenulatum. The seeds were found in the feces of two individuals captured in late-successional forests in the Colombian Amazon (one pregnant female and one adult male), that belonged to Piper sp. (n = 125) and Cecropia engleriana (n = 3). In germination experiments, only Piper seeds germinated (8%). Insectivores can potentially perform other functions than the role assigned to their corresponding guild. More research is needed on the natural history and ecology of G. crenulatum to elucidate its possible role as seed disperser.
DOI: 10.6084/m9.figshare.20005005
title: First record of leucism in the polychromatic Amazon tree boa, Corallus hortulana (Serpentes, Boidae) of South America

description: ABSTRACT Snakes have a wide variety of color patterns that can be related to specific ecological and physiological functions. However, genetic mutations can lead to the appearance of anomalous color patterns, which can directly interfere with the fitness of individuals. Leucism is a chromatic anomaly characterized by the almost total absence of epidermal and dermal chromatophores that produce the color. Corallus hortulana is an arboreal snake with nocturnal habits, widely distributed throughout South America, with a wide range of color patterns, known as polychromatism. Here we report the first case of leucism in Corallus hortulana and discuss the potential ecological implications of this anomaly in this species.
DOI: 10.6084/m9.figshare.20005005.v1
title: First record of leucism in the polychromatic Amazon tree boa, Corallus hortulana (Serpentes, Boidae) of South America

description: ABSTRACT Snakes have a wide variety of color patterns that can be related to specific ecological and physiological functions. However, genetic mutations can lead to the appearance of anomalous color patterns, which can directly interfere with the fitness of individuals. Leucism is a chromatic anomaly characterized by the almost total absence of epidermal and dermal chromatophores that produce the color. Corallus hortulana is an arboreal snake with nocturnal habits, widely distributed throughout South America, with a wide range of color patterns, known as polychromatism. Here we report the first case of leucism in Corallus hortulana and discuss the potential ecological implications of this anomaly in this species.