Brazilian Amazonian palm-stem types and uses: a review

ABSTRACT Palms may be an important source of renewable raw material to replace wood, however, the uses of the stems of native species of the Brazil are known only at the local or regional level. We carried out a literature review on the traditional knowledge of the uses of the stems of palm species native to the Amazon biome in Brazil, and related the types of uses with morphological characteristics of the stems. The review resulted in information on 45 species with solitary or cespitose stems, and six stem-size types: tall (15 species), medium-short (3), medium (5), small (17), acaulescent (1) and climbing (4). We found 80 indications of stem use in seven categories and 14 subcategories. A similarity analysis showed that, in general, tall, medium-short, medium, small (≥ 10 cm in diameter) and climbing stem types, solitary or cespitous, are used for construction, furniture, handicrafts, utensils, tools and musical instruments. Only small stems (< 10 cm diameter) are used to manufacture weapons for hunting and fishing, and climbing stems are used in the manufacture of ropes. Stems of Socratea exorrhiza, Euterpe oleracea and Desmoncus polyacanthos are the most frequently used to meet subsistence needs in traditional communities in the Brazilian Amazon. Our findings indicate that there is a potential for use of several native palm stems as sources for alternative materials in the manufacture industry and as sustainable income sources for Amazonian communities.

Ontogenetic skull variation in an Amazonian population of lowland tapir, Tapirus terrestris (Mammalia: Perissodactyla) in the department of Loreto, Peru

ABSTRACT The skulls of 54 specimens of the South American tapir, Tapirus terrestris collected in the department of Loreto, Peru were measured, analyzed and compared to investigate skull development of this species. Univariate, multivariate and allometric analyses were performed using 32 skull variables through traditional morphometrics. Significant skull shape variation was detected among ontogenetic classes. Young individuals (class I, n = 22) showed higher variation than subadults and adults (class II, n = 23 and class III, n = 9), without evidence of sexual dimorphism (males = 35, females = 19). Principal component analyses and discriminant function analysis showed almost complete separation of the age classes. Allometric analysis indicated a tendency of unproportioned cranial growth. All our samples come from the same population living under the same ecological condition, which eliminates the effect of confounding variables related to habitat on the pattern of ontogenetic variation of this anatomical structure.

Species-rich but defaunated: the case of medium and large-bodied mammals in a sustainable use protected area in the Amazon

ABSTRACT Neotropical medium and large-bodied mammals are key elements in forest ecosystems, and protected areas are essential for their conservation. In Brazil, sustainable use protected areas (SU-PAs) allow both the conservation of biodiversity and the sustainable use of natural resources, especially in the Amazon region. However, SU-PAs usually suffer both internal and external pressures, and may be subject to variable degrees of defaunation. We sampled mammals using camera traps in two areas with different forest management and human occupation history in the Tapajós National Forest (TNF), in the western Amazon. Overall, we recorded a rich assemblage of medium and large-sized mammals, though both areas differed in species composition. The area with older and more intense human occupation and forest exploitation had more independent records of generalist species, while large species such as Tapirus terrestris and Panthera onca were recorded exclusively in the area with lower human occupation and no forest management. A comparison of our results with similar studies in other Amazonian sites suggests a reduction in the population size of large-bodied mammals, such as Tapirus terrestris and Tayassu pecari, likely in response to increased human activities. Local differences in human occupation within and between protected areas are common in the Amazon, demanding area-specific actions from public authorities to minimize impacts on wildlife caused by human activities. Specifically in TNF, we recommend long-term monitoring of the responses of mammals to human activities, to better subsidize conservation and management actions.

Impacts of a large hydroelectric dam on the Madeira River (Brazil) on floodplain avifauna

ABSTRACT Hydroelectric dams represent an important threat to seasonally flooded environments in the Amazon basin. We aimed to evaluate how a dam in the Madeira River, one of the largest tributaries of the Amazonas River, affected floodplain avifauna. Bird occurrence was recorded through simultaneous passive acoustic monitoring in early successional vegetation and floodplain forest downstream from the dam and upstream in sites impacted by permanent flooding after dam reservoir filling. Species were identified through manual inspection and semi-automated classification of the recordings. To assess the similarity in vegetation between downstream and upstream sites, we used Landsat TM/ETM+ composite images from before (2009-2011) and after (2016-2018) reservoir filling. Downstream and upstream floodplain forest sites were similar before, but not after dam construction. Early successional vegetation sites were already different before dam construction. We recorded 195 bird species. While species richness did not differ between upstream and downstream sites, species composition differed significantly. Ten species were indicators of early successional vegetation upstream, and four downstream. Ten species were indicators of floodplain forest upstream, and 31 downstream. Seven of 24 floodplain specialist species were detected by the semi-automated classification only upstream. While we found some bird species characteristic of early successional vegetation in the upstream sites, we did not find most species characteristic of tall floodplain forest. Predominantly carnivorous, insectivorous, and nectarivorous species appear to have been replaced by generalist and widely distributed species.

Effect of Amazonian tree species on soil and pasture quality in silvopastoral systems

ABSTRACT With the expansion of livestock in the Amazon region, a high percentage of pasture areas are degraded and unproductive. Novel strategies are needed, including the use of native tree species, to simultaneously achieve economic and ecosystem benefits. This study aimed at assessing the effects of five multipurpose native tree species on soil fertility and forage quality of Urochloa brizantha pastures in the southern Amazon. Soil and forage samples were collected under the crown and adjacent to 25 isolated trees belonging to five species during a dry and a rainy season. The presence of native trees positively affected the level of potassium, calcium and manganese in the soil, as well as the mineral matter and crude protein of the forage, especially in the dry season, suggesting a protective effect against the seasonal drought. The tree species had variable effects on soil fertility and forage quality. Soil under Apeiba tibourbou had higher potassium levels, while the forage under Handroanthus serratifolius had higher protein and fiber content. Our results indicate that it is important to diversify silvopastoral systems in the Amazon through the use of native tree species, contributing to the design of novel silvopastoral strategies in the region. Common multipurpose tree species with widespread natural distribution could be used as a complementary aspect of pasture management to provide a protective effect against drought, contribute to enhanced nutrient cycling and even increase forage quality.

Identity of Gymnophthalmus (Squamata: Gymnophthalmidae) from northeastern Amazonia with evidence for G. underwoodi as invasive in Belém

ABSTRACT We report the occurrence of the lizard Gymnophthalmus underwoodi in the municipality of Belém, state of Pará, Brazil. This is the first record of that species south of the Amazonas River, probably because of an accidental introduction by ships that dock in Belém, the same pathway suggested for the recent introduction of another species of exotic lizard recently recorded in the city. We also determined the identity of some specimens of Gymnophthalmus from the states of Amapá and Pará through external morphology and molecular data, confirming that, until now, G. vanzoi is the only Gymnophthalmus occurring in the savanna enclaves of those states. Finally, we provide a new distribution map for the species of Gymnophthalmus, including the new occurrence record for G. underwoodi for the state of Pará, where it can be considered as an invasive species.

Wood and bark water content and monthly stem growth in Amazonian tree species

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 > 0.05). However, wood density was negatively correlated with WWC (r s = −0.69, p < 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 > 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.

Osteophagia by Nasutitermes guayanae (Blattodea: Isoptera: Termitidae) on human bone remains in the Andean Amazon, Caquetá, Colombia

ABSTRACT We present the first report of Nasutitermes guayanae feeding on human bone remains found in an urban area of the municipality of Florencia, Caquetá, Colombia, in the Colombian Amazon piedmont. The record indicates an expansion in the diet of these termites. The observation suggests that the association of N. guayanae with decomposing bodies may be a possible tool for the estimation of postmortem intervals.

Assessment of fire hazard weather indices in the eastern Amazon: a case study for different land uses

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.

Land use dynamics under the Bolsa Floresta Program: a case study of the Uatumã Sustainable Development Reserve (Amazonas, Brazil)

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.