The high degree of variability among suppliers and types of biomasses hinders their application in energy production. Investigation into this drawback is needed for the use of the waste produced from açaí depulping, which is widely available throughout the Amazonia. This work aimed to analyze the variability of the yield and physical properties of the açaí waste among different Amazonian producers located at Macapá, AP, Brazil. In addition, energetic attributes of different waste components, namely, seeds and lignocellulosic fibers, were compared to determine if they should be separated prior to burning or pyrolysis. The average yield (71.0%–95.0%), dry basis moisture content (66.6%–76.2%), and basic density (0.753 g cm−3 to 0.812 g cm−3) of açaí waste varied remarkably among the suppliers. Fibers and seeds depicted similar higher heating values (19.91 MJ kg−1 and 19.32 MJ kg−1) and fixed carbon (21.39% and 21.50%) and volatile matter (77.32% and 76.65%), while the ash content was slightly lower for seeds (1.29%–2.08%) in comparison to fibers (1.85%–2.63%). Thermogravimetric analysis revealed different initial degradation temperatures and mass loss rates for the seeds and fibers. It was concluded that the yield and physical properties of açaí waste varied remarkably among providers. A drying process should be carried out before açaí waste burning due to its high moisture content. The high basic density is an advantageous feature of açaí waste in the context of bioenergy. Separation of the components is recommended prior to pyrolysis to avoid heterogeneous charcoal.

The Brazil-nut tree (Bertholletia excelsa) is native to the Amazon rainforest, and its fruit production varies naturally with climatic conditions. Our aim was to evaluate the temporal variation in Brazil-nut production associated with climatic variables, including the strong El Niño of 2015/2016. The study was carried out in two 9-ha permanent plots in the northeastern Brazilian Amazon from 2007 to 2018: one in forest (12-year monitoring) and the other in savannah/forest transition (eight years). Overall, we monitored fruit production of 205 trees with diameter at breast height ≥ 50 cm. Annual fruit production was related to temporal series (2005-2018) of climatic data (the Oceanic Niño Index; and precipitation and air temperature from two local meteorological stations). Average fruit production per tree in 2017 was eight times lower than in 2015 and two times lower than the general average for both sites, and was significantly associated to the El Niño of 2015/2016, that increased average maximum monthly temperature and reduced the precipitation in the region, extending the dry season from three to six months. Years with higher and lower fruit production per tree coincided in both sites. Annual fruit production was significantly and negatively correlated with thermal anomalies that occurred in the third semester prior to harvest monitoring. Years with higher production were related with predominance of neutrality or the La Niña phenomenon at the global scale, and higher rainfall at the local scale. The relationship of fruit production with climate was independent of the local habitat.

Manejo florestal Estatística espacial pontual ExtrativismoA castanha-da-amazônia (Bertholletia excelsa Bonpl.) é uma espécie de grande concentração na Amazônia brasileira e possui grande valor cultural, social e econômico por se tratar de uma espécie muito utilizada por comunidades extrativistas da região. Sabe-se que indivíduos de uma determinada espécie podem apresentar diferentes padrões de distribuição espacial dentro de uma população vegetal, esses padrões estão correlacionados com fatores bióticos e abióticos e o seu entendimento é necessário para o auxílio de planejamento e manejo florestal. O objetivo deste trabalho foi identificar um padrão espacial das árvores de castanha-da-amazônia na floresta nativa no sul do Amapá. Foram implantadas três parcelas permanentes de 300 m x 300 metros na floresta madura de terra firme na Reserva Extrativista do Rio Cajari (RESEX Cajari), para verificar o padrão de distribuição espacial da espécie serão testadas as funções: F e K. No levantamento foram amostrados 169 indivíduos de castanha-da-amazônia nas três parcelas permanentes e a análise da completa aleatoriedade espacial foi confirmada em ambas parcelas nas duas funções testadas, e esse padrão pode ser explicado pela ação dos dispersores naturais. Não houve diferença no padrão de distribuição nas áreas estudadas, porque o extrativismo da castanha na região selecionou um grande número de indivíduos adultos nos castanhais por conta do diâmetro mínimo de produção (≥50 cm). Entretanto, por conta da dispersão zoocórica, novos indivíduos de castanheira podem estar se desenvolvendo em regiões mais abertas, por conta da maior disponibilidade de luz e preferência dos dispersores.

The Caatinga biome in Brazil comprises the largest and most continuous expanse of the seasonally dry tropical forest (SDTF) worldwide; nevertheless, it is among the most threatened and least studied, despite its ecological and biogeographical importance. The spatial distribution of volumetric wood stocks in the Caatinga and the relationship with environmental factors remain unknown. Therefore, this study intends to quantify and analyze the spatial distribution of wood volume as a function of environmental variables in Caatinga vegetation in Bahia State, Brazil. Volumetric estimates were obtained at the plot and fragment level. The multiple linear regression techniques were adopted, using environmental variables in the area as predictors. Spatial modeling was performed using the geostatistical kriging approach with the model residuals. The model developed presented a reasonable fit for the volume m 3 ha with r 2 of 0.54 and Root Mean Square Error (RMSE) of 10.9 m 3 ha -1 . The kriging of ordinary residuals suggested low error estimates in unsampled locations and balance in the under and overestimates of the model. The regression kriging approach provided greater detailing of the global wood volume stock map, yielding volume estimates that ranged from 0.01 to 109 m 3 ha -1 . Elevation, mean annual temperature, and precipitation of the driest month are strong environmental predictors for volume estimation. This information is necessary to development action plans for sustainable management and use of the Caatinga SDTF in Bahia State, Brazil.

O estudo realizou a análise da viabilidade econômica de dois modelos de transporte da produção de frutos de castanha-da-amazônia em uma empresa que se localiza no município de Almeirim/Pará. O mesmo foi formatado por meio de coleta de dados que foram transformados em informações para a realização da análise de investimento através de indicadores econômicos, obtidos por ferramentas de engenharia econômica, como o Valor Presente Líquido (VPL), que foi o principal método utilizado para a análise, outras ferramentas como, a Taxa Interna de Retorno (TIR), o Custo Anual Unitário (CAU) e o payback foram utilizados como auxilio na tomada de decisão. Além disso, foi realizada uma análise de sensibilidade e simulações de cenários prevendo possíveis variações na produção de sementes. Os modelos analisados agregam valor para a empresa, conforme os indicadores econômicos estudados, com destaque para o modelo 2 que apresentou algumas vantagens.

Patauá is very little studied palm tree of the Amazonia that shows lignocellulosic fibers covering the seed that can be easily removed. This work aimed to determine some properties of the patauá mesocarp fibers in the raw and alkali treated conditions for biomaterial applications. The wastes from the depulping of the patauá were obtained in commercial establishments at Macapá-Amapá-Brazil. The fibers were manually removed from the seeds. One portion of 10 g of fibers was treated by immersion in 1000 mL of sodium hydroxide (NaOH) aqueous solution at 5% kept at 100 °C for 1 h and under mechanical stirring. The following characterizations were performed: fiber length; scanning electron microscopy; width measurement; and basic density. The patauá mesocarp fibers are actually fiber bundles with erosions in the cell wall blocked by protrusions. They are suitable for large-scale production in both raw and alkali treated conditions. The improvements achieved by alkali treatment includes unblocking of superficial erosions, decrease of the width, length and basic density of the fibrous units, and increase of crystalline index. Individualization of fiber cells was not completed by the alkali treatment proposed in this work.