Spatial variability of soil fertility under agroforestry system and native forest in eastern Amazonia, Brazil

The usage of spatial tools might be helpful in the optimization of decision-making regarding soil management, with technologies that assist in the interpretation of information related to soil fertility. Therefore, the present study evaluated the spatial variability of chemical attributes of the soil under an agroforestry system compared to a native forest in the municipality of Tomé-açu, Eastern Amazon, Brazil. Soil samples were performed at 36 points arranged in a 55 x 55 m grid. The soils were prepared and submitted to analysis in order to determine pH in H2O, exchangeable calcium, magnesium, potassium and aluminium, available phosphorus, potential acidity, organic matter, bases saturation and aluminium saturation. For each soil attribute, the spherical, gaussian and exponential models were adjusted. After the semivariograms fitting, data interpolation for assessment of spatial variability of the variables was performed through ordinary kriging. The spherical and gaussian models were the most efficient models in estimation of soil attributes spatial variability, in most cases. Most of variables presented a regular spatial variability in their respective kriging maps, with some exceptions. In general, the kriging maps can be used, and we can take them as logistical maps for management and intervention practices in order to improve the soil fertility in the study areas. The results principal components indicate the need for integrated management of soil chemical attributes, with localized application of acidity correctors, fertilizers and other types of incomes, using the spatial variability of these fertility variables.

Mariposas frugívoras (Lepidoptera: Nymphalidae) en plantaciones de eucalipto y bosques de galería en la Orinoquia colombiana / Fruit-feeding butterflies (Lepidoptera: Nymphalidae) in eucalyptus plantations and gallery forests in the Colombian Orinoquia

Introducción: Una actividad económica que ha tenido auge en la última década en la altillanura es la forestación de sabanas con alteraciones antrópicas, pero se desconoce su papel en la conservación de las mariposas frugívoras de los bosques de galería dentro de los núcleos forestales. Objetivo: Comparar la diversidad de mariposas frugívoras en plantaciones de eucalipto y bosques de galería, y el papel de las variables ambientales. Métodos: Utilizamos trampas Van Someren-Rydon, dos réplicas de cuatro trampas, en cada uno de los cuatro hábitats muestreados simultáneamente desde diciembre 2020 hasta julio 2021: plantación de eucaliptos de cuatro años; plantación de eucaliptos de seis años; bosque de galería de suelo seco y bosque de galería anegado. También registramos diez variables abióticas, estructurales, alimentarias y de hábitat. Resultados: Recolectamos 227 especímenes de mariposas frugívoras (30 especies, 23 géneros y 5 subfamilias de la familia Nymphalidae). Había más especies en los bosques. Las especies de mariposas variaron más del 50 % entre los hábitats; Satyrinae fue más diversa en las plantaciones. Conclusión: La forestación en esta área proporciona hábitats para algunas especies de mariposas frugívoras de los remanentes de bosques naturales adyacentes. Las forestaciones representan un escenario de alteración intermedia entre las dos unidades de paisaje dominantes en la región.

Introduction: An economic activity that has boomed in the last decade in Colombian highlands is the afforestation of anthropized savannas, but its role in the conservation of fruit-feeding butterflies of gallery forests within forest cores is unknown. Objective: To compare the diversity of fruit-feeding butterflies in eucalyptus plantations and gallery forests, and the role of environmental variables. Methods: We used Van Someren-Rydon traps, two replicates of four traps, on each of four habitats sampled simultaneously from December 2020 to July 2021: four-years-old eucalyptus plantation; six-years-old eucalyptus plantation; dry soil gallery forest and waterlogged gallery forest. We also recorded ten abiotic, structural, food and habitat variables. Results: We collected 227 specimens of fruit-feeding butterflies (30 species, 23 genera, and 5 subfamilies within the family Nymphalidae). There were more species in the forests. The butterfly species varied over 50 % between the habitats; Satyrinae were more diverse in plantations. Conclusion: Afforestation in this area provides habitats for some species of fruit-feeding butterflies from adjacent natural forest remnants. Afforestations represent an intermediate disturbance scenario between the two dominant landscape units in the region.

Regional concentration of native fuelwood production in Rio Grande do Norte, Brazil (1990­2017) / Concentração regional da produção de lenha nativa no Rio Grande do Norte, Brasil (1990-2017)

This paper examined the regional concentration of native fuelwood production in Rio Grande do Norte, Brazil, between 1990-2017. Information on native fuelwood was gathered from forestry activities collected by the Brazilian Institute of Geography and Statistics (IBGE). This study analyzed the current situation and the spatial distribution of the state's fuelwood production by quartiles. The following indicators were used to measure market concentration: Gini Coefficient (G), Comprehensive Concentration Index (CCI), Herfindahl-Hirschman Index (HHI) and Concentration Ratio [CR(k)]. In Rio Grande do Norte, there was a -2.76% annual decrease in the production of native fuelwood, from 5,280 x10³ m³ (1990) to 777 x10³ m³ (2017). Classification of the municipalities by quartile revealed that most municipalities had low fuelwood production. The G inferred a very strong to absolute inequality for the municipalities and a weak to null inequality for the mesoregions.The CCI demonstrated no market concentration in the municipalities and a regional concentration in the mesoregions. The HHI corroborated the CCI by affirming the presence of a competitive market for the municipalities and microregions and a concentrated market in the mesoregions.The CR(k) of the four largest municipalities indicated a moderately low concentration. This study concluded that there is a competitive market structure for native fuelwood inthe state of Rio Grande do Norte.

Este artigo analisou a concentração regional da produção de lenha nativa do Rio Grande do Norte - Brasil, no período de 1990 a 2017. As informações da lenha nativa foram obtidas da produção da extração vegetal e da silvicultura, disponíveis no Instituto Brasileiro de Geografia e Estatística (IBGE). Analisou a conjuntura, a distribuição espacial da produção de lenha estadual por meio os quartis e mensurou a concentração por meio dos indicadores: Coeficiente de Gini (G), Índice de Concentração Compreensiva (CCI), Índice de Herfindahl-Hirschman (HHI) e Razão de Concentração [CR(k)]. Os resultados mostraram que houve decréscimo de -2,76% a.a. na produção de lenha nativa estadual, partindo de 5.280 x10³ m³ (1990) para 777 x10³ m³ (2017). O quartil municipal revelou que a maioria dos municípios produz pouca lenha; apesar do G ter inferido uma desigualdade muito forte a absoluta para os municípios produtores de lenha e fraca a nula para as mesorregiões, já o CCI mostrou para os municípios que é não concentrado e as mesorregiões tem concentração regional; HHI corroborou com esta afirmação mostrando um mercado altamente competitivo para os municípios e microrregiões e concentrado para as mesorregiões produtoras de lenha; o CR(k) dos quatro maiores municípios foi constatada uma concentração moderadamente baixa. Conclui-se que a lenha nativa do estado do Rio Grande do Norte possui estrutura de mercado competitiva.

Potencial de reducción de emisiones y captura de carbono en bosques y sistemas agroforestales con cacao en el Pacífico colombiano / Potential for reducing emissions and carbon sequestration in forests and cocoa agroforestry systems in the Colombian Pacific

Resumen Introducción: Los bosques y sistemas agroforestales (SAF) suministran bienes y servicios ecosistémicos para la sociedad, tal como la mitigación del cambio climático. Objetivo: Se estimó el potencial de reducción de emisiones y captura de carbono en bosques y SAF con cacao de la subcuenca del río Munguidó, Colombia. Métodos: Se seleccionaron tres sistemas de uso del suelo (bosque primario, bosque secundario y SAF con cacao). Se establecieron 18 parcelas temporales de muestreo, seis por sistema, para medir los árboles (diámetro a la altura del pecho -dap ≥ 10 cm) y arbustos de cacao. Se cuantificó la biomasa aérea con ecuaciones alométricas y una fracción de carbono de 0.5. Se estimó la fijación de carbono en el bosque secundario y el SAF con cacao como la razón entre el carbono almacenado y su edad. La pérdida de carbono del bosque primario se estimó con base en la deforestación para Chocó y dicha subcuenca (0.6 y 0.3 %/año, respectivamente). Se realizó un análisis de varianza y comparación de medias LSD Fisher para determinar las diferencias en el almacenamiento y la fijación de carbono entre los usos. Resultados: El bosque primario almacenó más carbono que el bosque secundario y el SAF con cacao (190.1, 22.3 y 5.3 Mg/ha, respectivamente). La fijación de carbono del bosque secundario y el SAF con cacao no difirieron (2.23 vs 1.33 Mg/ha/año). En 20 años, el bosque primario presentaría una reducción de emisiones de 1.4-2.6 Tg CO2; y el bosque secundario y el SAF con cacao presentarían una captura de 100.8 y 30.7 Gg CO2, respectivamente. Conclusiones: En la subcuenca del río Munguidó es posible establecer proyectos para la reducción de emisiones en bosque primario y captura de carbono en bosques secundarios y SAF con cacao, con lo cual se podría emitir 1.4-2.6 millones de toneladas de CO2.

Abstract Introduction: Forests and agroforestry systems (AFS) provide ecosystem goods and services for society, such as climate change mitigation. Objective: The potential for emission reductions and carbon sequestration in forests and cocoa agroforestry systems in the Munguidó river sub-basin in Colombia was estimated. Methods: Three land use systems were selected (primary forest, secondary forest and AFS with cocoa). Eighteen temporary sampling plots were established, six per system, to measure trees (diameter at breast height -dbh ≥ 10 cm) and cocoa shrubs. Aboveground biomass was quantified with allometric equations and a carbon fraction of 0.5. Carbon fixation in secondary forest and AFS with cocoa was estimated as the ratio of carbon stored to its age. Carbon loss from primary forest was estimated based on deforestation for Chocó and that sub-basin (0.6 and 0.3 %/year, respectively). An analysis of variance and LSD Fisher mean comparison was performed to determine differences in carbon storage and carbon sequestration between uses. Results: Primary Forest stored more carbon than secondary forest and AFS with cocoa (190.1, 22.3 and 5.3 Mg/ha, respectively). The carbon fixation of secondary forest and AFS with cocoa did not differ (2.23 vs. 1.33 Mg/ha/year). In 20 years, the primary forest would present an emission reduction of 1.4-2.6 Tg CO2; and the secondary forest and the PFS with cocoa would present a sequestration of 100.8 and 30.7 Gg CO2, respectively. Conclusion: In the Munguidó river sub-basin, it is possible to establish projects for the reduction of emissions in primary forest and carbon sequestration in secondary forests and AFS with cocoa, which could emit 1.4-2.6 million tons of CO2.

Tree structure and diversity of a Humid Mountain Forest in the protected natural area La Martinica, Veracruz, Mexico / Estructura y diversidad arbórea de un bosque húmedo de montaña en el Área Natural Protegida La Martinica, Veracruz, México

Abstract Introduction: The Humid Mountain Forest (HMF) has the highest number of plants per unit of surface, whose vegetation grows under heterogeneous environmental conditions and possess a high floristic variation. HMF conservation is important due to the biodiversity it harbors and the environmental services it provides. Objective: This work evaluated the effect of the terrain aspect and density of the forest canopy on the structure and tree diversity in La Martinica Protected Natural Area, Mexico. Methods: Stratified sampling was performed in four terrain aspects and two canopy density conditions. Twenty five sampling units of 20 x 25 m were considered, in which the normal diameter (ND), total height and the largest and smallest diameters of the crown of the individuals with a ND ≥ 10 cm were registered. The diversity was estimated by rarefaction curves and the structure was analyzed through the importance value index (IVI) and the forest value index (FVI). Results: 37 species belonging to 30 genera and 24 families were recorded. Greater diversity was observed in the north terrain aspect and in the closed canopy. Tree species with the highest structural values were different between terrain aspect and canopy types; Carpinus tropicalis presented the highest values in the zenithal terrain aspect, Lippia myriocephala in the east and south terrain aspect, and Liquidambar styraciflua in the north. In both canopy types Lippia myriocephala obtained the highest IVI values and FVI in the open canopy; Carpinus tropicalis reached a higher FVI in the closed canopy. Conclusions: Tree structure was different in the four terrain aspects and two canopy conditions studied. The greatest difference in species composition and diversity was observed between the north and east terrain aspects; the north presented the highest richness values, frequent and dominant species.

Resumen Introducción: El Bosque Húmedo de Montaña (BHM) posee el mayor número de especies vegetales por unidad de superficie, cuya vegetación se desarrolla en condiciones ambientales muy heterogéneas y presenta una alta variación florística. La conservación del BHM es importante debido a la biodiversidad que alberga y los servicios ambientales que proporciona. Objetivo: Este trabajo evaluó el efecto de la orientación del terreno y la densidad del dosel del bosque sobre la estructura y diversidad arbórea en el Área Natural Protegida La Martinica, México. Métodos: Se efectuó un muestreo estratificado en cuatro orientaciones del terreno y dos condiciones de densidad del dosel; se consideraron 25 unidades de muestreo de 20 x 25 m, en las que se registró: el diámetro normal (DN), la altura total y los diámetros mayor y menor de la copa de los individuos con un DN ≥10 cm. La diversidad se estimó por medio de curvas de rarefacción y la estructura se analizó con el índice de valor de importancia (IVI) y el índice de valor forestal (IVF). Resultados: Se registraron 37 especies pertenecientes a 30 géneros y 24 familias. Se observó una mayor diversidad en la orientación norte y en el dosel cerrado. Las especies arbóreas con valores estructurales más altos fueron diferentes entre orientaciones y tipos de dosel; Carpinus tropicalis presentó los valores más elevados en la orientación cenital, Lippia myriocephala en las orientaciones este y sur, y Liquidambar styraciflua en la norte. En ambos tipos de dosel Lippia myriocephala obtuvo los valores más altos del IVI e IVF en el dosel abierto; Carpinus tropicalis alcanzó un IVF más elevado en el dosel cerrado. Conclusiones: La estructura arbórea fue diferente en las cuatro orientaciones estudiadas y en las dos condiciones del dosel. La mayor diferencia en composición de especies y diversidad se observó entre las orientaciones norte y este, de ellas, la norte presentó los valores más altos de riqueza, especies frecuentes y dominantes.

Efeitos de longo prazo do espaçamento de plantio no crescimento e morfometria de Bertholletia excelsa / Long-term effects of plant spacing on the growth and morphometry of Bertholletia excelsa

O espaçamento de plantio determina a forma e produtividade das árvores em plantações florestais. Entretanto, seus efeitos sobre a produtividade de plantações de espécies arbóreas da Amazônia ainda são pouco compreendidos. Objetivou-se examinar os efeitos de seis regimes de espaçamento (3 x 4, 4 x 4, 4 x 5, 5 x 5, 5 x 6, e 6 x 6 m) sobre o crescimento e morfometria de plantações de Bertholletia excelsa aos 20 anos de idade. Observamos alta sobrevivência independentemente do espaçamento (> 70%). Para fins de produção de madeira, os regimes de espaçamento intermediário e dois maiores apresentaram valores mais altos de características de produção, principalmente diâmetro, biomassa e volume, embora alguns não diferiram significativamente do menor espaçamento. Um dos espaçamentos intermediários (5 x 5 m) tendeu a maior altura comercial. As copas das árvores tenderam a ser mais largas e longas nos espaçamentos maiores, indicando potencial desses regimes para a produção de frutos. As copas das árvores excederam o espaço vital de crescimento em todos os espaçamentos, sugerindo a necessidade de desbaste antes dos 20 anos em todos os espaçamentos, para reduzir a competição intraespecífica e aumentar a produtividade. Estimamos que uma densidade de 84 árvores remanescentes por hectare seria necessária para atingir um diâmetro médio de 40 cm aos 20 anos. Portanto, B. excelsa apresentou alta sobrevivência em todos os regimes de espaçamento testados, enquanto os regimes de espaçamento intermediário e maiores proporcionaram melhor crescimento e morfometria das árvores. (AU)

Salud y trabajo forestal en el Uruguay: una aproximación participativa y cualitativa a su fase primaria / Health and forestry work in Uruguay: a participatory and qualitative approach to its primary phase

En los últimos treinta años la forestación se consolidó como sector productivo en Uruguay. A pesar de este crecimiento son escasos los estudios en cuanto a las condiciones de salud de sus trabajadores/as. En función de este problema y de un pedido de formación en salud laboral por parte del sindicato, esta investigación tuvo como objetivo describir el proceso de trabajo en cosecha y viveros forestales, y analizar los procesos peligrosos y positivos para la salud de los/as trabajadores/as. Para esto se diseñó un estudio exploratorio, observacional y descriptivo. Desde un enfoque cualitativo y participativo se realizaron 2 entrevistas en profundidad, 3 talleres de investigación y 2 instancias de restitución de resultados. El trabajo integró a 45 delegados/as en salud laboral y referentes sindicales de distintas empresas, sectores y departamentos del país. Los procesos peligrosos más destacados por los/as trabajadores/as se vincularon con el ambiente de trabajo, la manipulación de sustancias tóxicas y los movimientos estáticos y/o repetitivos. Estos se intensifican a partir del pago por productividad, las presiones en calidad y la diversidad de empresas tercerizadas. En el sector estudiado, los modos de organizar el trabajo son transversales a los procesos peligrosos analizados e inciden en su intensidad. Este diagnóstico colectivo permitió planificar una estrategia conjunta de formación y de promoción de la salud ajustada a las particularidades de la forestación en Uruguay(AU)

Over the past 30 years, forestry has become a consolidated production sector in Uruguay. Despite this growth, there are few studies on health conditions of workers. Based on this problem and a request for occupational health training from the sector's trade union, this exploratory, observational and descriptive study aimed to describe the work processes in forest harvesting and nurseries, and analyze the hazardous and positive processes for workers' health. Using a qualitative and participatory approach, we conducted two in-depth interviews, three research workshops and two sessions on results dissemination. Our study involved 45 occupational health delegates and trade union representatives from different companies, sectors and departments in the country. Most of the hazardous processes were linked to the work environment, handling of toxic substances and static and/or repetitive movements. These were intensified by productivity payments, pressures on quality and the variety of subcontractor companies. In this sector, the ways of organizing work cut across the hazardous processes identified and impact their severity. This collective diagnosis allowed us to plan a joint training and health promotion strategy, adapted to the Uruguayan forestry sector(AU)

Host status of eucalypt species to Pratylenchus brachyurus and Meloidogyne incognita

Plant parasitic nematodes are major threats to Brazilian and world agriculture. Among them, Pratylenchus brachyurus and Meloidogyne incognita stand out as major pests for several crops, including corn, cotton, soybean among others, which can be components of integrated crop-livestock-forestry systems (ICLFs). In this context, information about the host status of eucalypts (Corymbia spp. and Eucalyptus spp.) to plant parasitic nematodes becomes more relevant in Brazil, due to the use of eucalypts in ICLFs. If tree components used on this system increase the population density of P. brachyurus and M. incognita, it is possible that these pathogens could damage shorter-cycle crops. Since information about the host status of eucalypts to plant parasitic nematodes is scarce, this study evaluated the host status of some eucalypt species to P. brachyurus and M. incognita. Two greenhouse trials were done to evaluate the reproduction of P. brachyurus and one to M. incognita, using some of the most cultivated species and hybrids of eucalypts in Brazil. The population growth of P. brachyurus increased on Corymbia citriodora, Eucalyptus grandis, Eucalyptus dunnii × Eucalyptus urophylla, and E. grandis × E. urophylla after ~90 days of inoculation. Conversely, despite M. incognita reproducing well in the control plants, no individuals were recovered from C. citriodora, E. urophylla and E. grandis × E. urophylla, which were classified as resistant plants. Based on both obtained and available data, M. incognita poses no threat to eucalypt species today. However, P. brachyurus is suggested to be a threat to eucalypts.

Almacenamiento de carbono en sistemas agroforestales en los Llanos Orientales de Colombia / Carbon storage in agroforestry systems in Colombia's Eastern Plains

Introducción: Los cultivos de café, cacao y pasturas para la ganadería son actividades agropecuarias de interés económico en Colombia. Cuando estas actividades se desarrollan bajo sistemas agroforestales (SAF) promueven la conservación e incrementan la fijación de carbono y, por ende, la mitigación del cambio climático. Objetivo: El estudio estimó el almacenamiento de carbono en la biomasa aérea, necromasa y carbono orgánico del suelo bajo SAF con cacao (SAF cacao), SAF con café (café SAF), sistemas silvopastoriles (SSP) y bosque en el municipio de Mesetas, Meta (Colombia). Métodos: Se establecieron 44 parcelas de muestreo, en donde se tomaron medidas dasométricas a individuos con un diámetro del tronco a la altura del pecho (dap) ≥ 2.5 cm (latizales, fustales y fustales grandes), cuyos valores fueron transformados a carbono con modelos de biomasa y una fracción de carbono default. En los tres sistemas agropecuarios, se contó el número de árboles de cacao, café, plantas asociadas y se identificó el tipo de uso (maderable, alimento, combustión). Resultados: El almacenamiento de carbono presentó diferencias significativas (P < 0.0001) entre usos del suelo. La mayor acumulación se encontró en bosque, con 216.6 t C ha-1, superando en 59, 72 y 73 % a SAF cacao, SSP y SAF café, respectivamente. Fabaceae, Lauraceae y Primulaceae presentaron el mayor almacenamiento de carbono. En SAF cacao, la mayor acumulación de carbono fue encontrada en especies para alimento humano; en SAF café y SSP, el mayor almacenamiento fue presentado en las especies maderables. Conclusión: Estos resultados resaltan el potencial de almacenamiento de carbono en los sistemas productivos de mayor importancia en el departamento del Meta, lo cual es importante para el diseño de estrategias que permitan integrar acciones de mitigación de emisiones de gases de efecto invernadero y promover la economía campesina local.

Introduction: Coffee, cocoa crops and pastures for livestock are agricultural activities of economic interest in Colombia. When these activities are developed under agroforestry systems (AFS), they promote conservation and increase carbon fixation and, therefore, climate change mitigation. Objective: The study estimated carbon storage in aboveground biomass, necromass and soil organic carbon under SAF with cocoa (SAF cocoa), SAF with coffee (SAF coffee), silvopastoral systems (SPS) and forest in Mesetas, Meta (Colombia). Methods: Forty-four sampling plots were established, where dasometric measurements were taken from individuals with a trunk diameter at breast height (dbh) ≥ 2.5 cm (saplings, trees and large trees), whose values were transformed to carbon with biomass models and a default carbon fraction. In the three agricultural systems, the number of cocoa and coffee trees and associated plants was counted, and the type of use (timber, food, combustion) was identified. Results: Carbon storage showed significant differences (P < 0.0001) among land uses. The highest accumulation was found in forest, with 216.6 t C ha-1, exceeding in 59, 72 and 73 % to SAF cocoa, SSP and SAF coffee, respectively. The botanical families Fabaceae, Lauraceae and Primulaceae presented the greatest carbon storage. In SAF cocoa, the greatest accumulation of carbon was found in species for human food; in SAF coffee and SSP, the greatest storage was presented by timber species. Conclusion: These results highlight the potential for carbon storage in the most important productive systems in the Meta department, which is important for designing strategies that allow for integrating actions to mitigate greenhouse gas emissions and to promote the local peasant economy.

Contributions of Complexity Approaches to Innovative Forestry Development / Aportes de los enfoques de la complejidad para un desarrollo forestal innovador

RESUMEN El objetivo de este artículo fue contribuir a la reflexión sobre los aportes de la complejidad al desarrollo forestal a partir del caso peruano, lo cual podría servir como orientación para otros países de América Latina. El artículo recoge las propuestas que surgieron en tres jornadas denominadas "Complejidad y desarrollo forestal" organizadas por el Capítulo de Ingenieros Forestales del Colegio Departamental de Lima, Colegio de Ingenieros del Perú, realizadas entre 2018 y 2019. Se concluye que el enfoque disciplinario y sectorial de la administración forestal es insuficiente para abordar la complejidad de la realidad; consecuentemente para tratar el desarrollo forestal desde una perspectiva innovadora, existe la necesidad de incorporar el enfoque de la complejidad desde las ciencias de la complejidad y el pensamiento complejo que se traduzca en nuevas maneras de pensar y actuar.

ABSTRACT The objective of this article is to contribute to the reflection on the contributions of complexity to forest development, based on the Peruvian case, which could serve as a guide for other Latin American countries. The article gathers the proposals that arose in three days called "Complexity and Forest Development", organized by the Chapter of Foresters of the Departmental College of Lima of the Association of Engineers of Peru, carried out between 2018 and 2019. It was concluded that the disciplinary and sectorial approach of forest administration is insufficient to address the complexity of reality. Consequently, in order to address forest development from an innovative perspective, there is a need to incorporate the approach to complexity from the sciences of complexity and complex thinking, which translates into new ways of thinking and acting.

Vegetative rescue potential of Brazil nut through epicormic shoots on detached branches

Obtaining juvenile material may favor the clonal propagation of Brazil nut, Bertholletia excelsa. We aimed to assess the emission of epicormic shoots on detached branches of Brazil nut trees as a function of the mother tree and branch diameter, in order to provide juvenile material for use in clonal multiplication. The experimental design was completely randomized in a 6 (mother trees) x 3 (stem diameter: < 20 20-40 and 40-80 mm) factorial design, with four replicates. Every five days the number of shoots emitted was counted and the sprouting speed index and average sprouting time were calculated. The number of epicormic shoots and the sprouting speed index were dependent on the interaction between mother tree and branch diameter. Branches with larger diameter (20-40 and 40-80 mm) showed higher potential for obtaining propagules for use in Brazil nut clonal multiplication (cutting, grafting and in vitro cultivation). (AU)

Aproximaciones para el desarrollo de una bioética forestal a partir del caso peruano / Approaches to developing a forest bioethics from the Peruvian case / Aproximações para o desenvolvimento de uma bioética florestal a partir do caso peruano

Resumen: El presente artículo tiene como objetivo primario reflexionar sobre cómo la bioética puede dar luces para un desarrollo forestal más comprometido con la vida en general. El estudio se focaliza en el Perú; sin embargo, se toma en cuenta información bibliográfica especializada de otros países con bosques tropicales. Se concluye que, aunque hay importantes avances científicos en el conocimiento sobre los bosques tropicales y expectantes experiencias certificadas de manejo forestal, no existe suficiente certeza científica que garantice su sustentabilidad ecológica. Lo anterior es producto tanto de la propia complejidad ecológica de los bosques tropicales, como de la complejidad sociocultural del sector forestal; lo que demanda aproximaciones que complementen los enfoques disciplinarios con perspectivas interdisciplinarias y transdisciplinarias. La realidad de los bosques es multidimensional, interdimensional, multiescalar y multitemporal; esta condición no logra ser captada por los planes de manejo forestal que descansan en el paradigma de una ciencia racional y empírica. A pesar de que hay valiosas medidas orientadas a la conservación de la biodiversidad forestal y previsiones para luchar contra la tala ilegal, el comercio y tráfico ilegal de la fauna silvestre, estas medidas para reducir la ilegalidad aún no son suficientes. A la fecha no existe una orientación específica sobre el respeto a la vida en el bosque en todas sus manifestaciones; además, los intentos que buscan la conservación de las especies de flora y fauna son desarticulados.

Abstract: The main objective of this article is to reflect on how bioethics can shed light on forest development that is more committed to life in general. The study focuses on Peru; however, specialized bibliographic information from other countries with tropical forests is considered. It is concluded that, although there are important scientific advances in knowledge about tropical forests and expectant certified experiences in forest management, there is not enough scientific certainty to guarantee their ecological sustainability. This is a product of both the ecological complexity of tropical forests and the socio-cultural complexity of the forest sector; which demands approaches that complement disciplinary approaches with interdisciplinary and transdisciplinary perspectives. The reality of forests is multidimensional, interdimensional, multiscale and multitemporal; this condition cannot be grasped by forest management plans that lie on the paradigm of a rational and empirical science. Although there are valuable measures aimed at conserving forest biodiversity and provisions to combat illegal logging, illegal trade and trafficking of wildlife, these measures to reduce illegality are still not enough. To the date there is no specific guidance on respect to forest life in all its manifestations, and in addition to that, attempts seeking to conserve the species of flora and fauna are disarticulated.

Resumo: O objetivo principal deste estudo é refletir sobre como a bioética pode guiar um desenvolvimento florestal mais comprometido com a vida em geral. O estudo está focado no Peru; contudo, é considerada informação bibliográfica especializada de outros países com florestas tropicais. Conclui-se que, embora haja importantes avanços científicos no conhecimento sobre as florestas tropicais e esperadas experiências certificadas de gestão florestal, não existe suficiente certeza científica que garanta sua sustentabilidade ecológica. Isso é produto tanto da própria complexidade ecológica das florestas tropicais quanto da complexidade sociocultural do setor florestal, o que demanda aproximações que complementem as abordagens disciplinares com perspectivas inter e transdisciplinares. A realidade das florestas é multi e interdimensional, multiescalar e multitemporal. Essa condição não consegue ser captada pelos planejamentos de gestão florestal que se baseiam no paradigma de uma ciência racional e empírica. Apesar de haver valiosas medidas orientadas à conservação da biodiversidade florestal e previsões para lutar contra o desflorestamento ilegal, o comércio e o tráfico ilegal da fauna silvestre, as medidas para reduzir a ilegalidade ainda não são suficientes. Até o momento não existe uma orientação específica sobre o respeito à vida na floresta em todas as suas manifestações; além disso, as tentativas da conservação das espécies de flora e fauna são desarticuladas.

Influence of fertilizer and hydrogel on physical-chemical attributes of substrate for seedling production / Influência de adubação e hidrogel nos atributos físico-químicos de substrato para produção de mudas florestais

The incorporation of the hydrogel into the substrate used in the forest nursery promotes improvements in its physical-chemical attributes. However, several factors influence the hydrogel efficiency, such as the increase of salts, promoted by fertilizer of the substrate. Therefore, this study aimed to evaluate the effects of the incorporation of fertilizer levels and hydrogel doses on the physical-chemical attributes of a substrate to produce forest seedlings. Different levels of basic fertilizer commonly used in the nursery (100%, 50% and 0%) and different doses of the hydrogel (0, 1, 2 and 3 g L-1) were incorporated into the substrate Tropstrato Florestal®, consisting of 12 treatments in a 3 x 4 factorial scheme. A sample of the substrate in each treatment was sent for analysis of its physical and chemical attributes. To evaluate the effect of the treatments on the physical-chemical attributes of the substrate, was used the multivariate principal components analyses. The levels of fertilizer and hydrogel doses were correlated with the attributes of the substrates obtained in each treatment. The incorporation of different fertilizer levels and hydrogel doses to the substrate modified their chemical and physical attributes. Fertilizers have influenced mainly the chemical attributes of the substrate, whereas hydrogels have influenced the physical attributes, mainly those related to water retention capacity and availability.

A incorporação do hidrogel ao substrato utilizado no viveiro florestal promove melhorias em seus atributos físico-químicos. Porém vários fatores influenciam na eficiência do hidrogel, como o aumento de sais, promovido pela adubação do substrato. Portanto, este estudo teve como objetivo avaliar os efeitos da incorporação de níveis de adubação e doses de hidrogel sobre os atributos físico-químicos de um substrato para a produção de mudas florestais. Foram incorporados ao substrato Tropstrato Florestal® diferentes níveis da adubação de base comumente utilizada no viveiro (100%, 50% e 0%) e diferentes doses do hidrogel (0, 1, 2 e 3 g L-1), consistindo em 12 tratamentos em esquema fatorial 3 x 4. Uma amostra do substrato em cada tratamento foi encaminhada para análise de seus atributos físicos e químicos. Para avaliar o efeito dos tratamentos sobre os atributos físico-químicos do substrato foi utilizada a análise multivariada de componentes principais. Os níveis de adubação e doses de hidrogel foram correlacionados com os atributos dos substratos obtidos em cada tratamento. A incorporação de diferentes níveis de adubação e doses de hidrogel ao substrato modificaram seus atributos químicos e físicos. A adubação influenciou principalmente os atributos químicos do substrato, enquanto que o hidrogel os atributos físicos, principalmente os relacionados à capacidade de retenção e disponibilidade de água.

Silvicultural performance of eucaliptus and animal behavior in a silvopastoral system / Desempenho silvicultural de eucalipto e comportamento animal em sistema silvipastoril

Silvopastoral system, in which trees and forage species are grown in the same area together with animals, has emerged as a sustainable alternative of agricultural production systems. However, information on different silvicultural arrangements and combinations of forest, animal and grazing components in this system are still scarce. Thus, this study followed the silvicultural performance of the forest component (Eucalyptus urophylla x E. grandis, eucalyptus hybrid, clone I-144) under different population arrangements in a silvopastoral system through periodic dendrometric evaluations and determined the impact of animal component (Nellore females) on tree development and ingestive behavior of animals subjected to rotational grazing in Urochloa brizantha cv. Marandu. The study was conducted at Agropecuária Ouro Branco, located in Bandeirantes, MS, Brazil. Total height, diameter at breast height, and wood volume per hectare were evaluated in three- and five-row ranks. To indicate plant growth, the current and average annual increments werecalculated. Animal behavior was evaluated based on the periodic observation of 15 animals randomly selected in the lot. The initial performance of forest component was satisfactory in both populations, but growth indicators indicated greater current and average annual increments in the five-row rank. The presence of forest component does not interfere with the ingestive behavior and wellbeing of animals in the silvopastoral system, as well as, the presence of animal component does not interfere in the plants silvicultural development.

O sistema silvipastoril, onde espécies arbóreas e forrageiras são cultivadas em uma mesma área, conjuntamente com o componente animal, vem se despontando como uma alternativa sustentável de sistemas de produção agrícola, no entanto, informações sobre os diferentes arranjos silviculturais e combinações dos componentes arbóreo, animal e pastagem no sistema ainda são incipientes. Assim, este estudo teve como objetivo acompanhar o desenvolvimento inicial do componente florestal (Eucalyptus urophylla x E. grandis, híbrido de eucalipto, clone I-144), em diferentes arranjos populacionais, em sistema silvipastoril, por meio de avaliações dendrométricas periódicas; e, determinar o impacto da inserção do componente animal(fêmeas da raça Nelore) sobre o desenvolvimento das árvores e sobre o comportamento ingestivo dos animais submetidos ao pastejo rotacionado em Urochloa brizantha cv. Marandu. O estudo foi realizado na Agropecuária Ouro Branco, situada em Bandeirantes, MS. Tanto nos renques de três, como no de cinco fileiras, foram avaliados a altura total (H), diâmetro a altura do peito (DAP) e volume de madeira por hectare. Para indicar o crescimento das plantas, foram calculados o Incremento Corrente Anual (ICA) e o Incremento Médio Anual (IMA). O comportamento dos animais foi avaliado baseado na observação periódica de 15 animais selecionados aleatoriamente no lote. Verificou-se que o desempenho inicial do componente arbóreo, em ambos os arranjos populacionais, mostrou-se satisfatório, no entanto, os indicadores de crescimento, apontam para um maior incremento corrente e médio anual nas plantas dos renques com cinco fileiras. A presença do componente arbóreo não interfere no comportamento ingestivo e bem-estar dos animais locados no sistema, assim como, a presença dos animais não interfere no desenvolvimento silvicultural das plantas.

Musa acuminata pseudostem extract on the control of atta sexdens rubropilosa / Extrato de pseudocaule de Musa acuminata no controle de Atta sexdens rubropilosa

Currently, few active principles are authorized by the forest certification for the control of insect pests, with which it is necessary to develop new products, mainly aiming at lower environmental impact. The plants are able to develop substances called secondary metabolites, widely studied as an alternative form of pest control. Thus, the objective of this study was to evaluate the insecticidal potential of two Musa acuminata extracts, on the control of Atta sexdens rubropilosa. The extracts were obtained from the pseudostem of M. acuminata, which underwent drying and milling, producing two extracts: ethanolic (A1) and hydroethanolic rotaevaporate (A2) extract. For the analysis of the bioactivity of the extracts, a topical application of one milliliter of each extract on the ants was carried out, with the aid of spray, in the concentrations of: 2, 6, 10, 14, 18, and 20%, with distilled water (witness) applied to the test, analyzing the mortality and LC50, in different evaluation periods. At 24 hours the mortality of 90% at the concentration of 20% for the A1 extract was observed. From the 10% concentration there was 100% mortality in this same period for the A2 extract, and at 48 hours the 2% concentration caused 100% mortality. In the LC50 analysis for 24 hours values of 7.94 and 1.09% were obtained for ethanolic extract and rotavaporated ethanolic extract respectively. And the LC50 presented a decrease in values after 48 hours for the ethanolic extract presented value of 2.29%. Thus, it can be concluded that the A2 extract is the most efficient, since it allows the lower consumption of extract in the dilution for later application, due to the presence of insecticidal potential in low concentration.

Atualmente, poucos princípios ativos são autorizados pela certificação florestal para o controle de insetos-praga, sendo necessário desenvolver novos produtos, principalmente visando menor impacto ambiental. As plantas são capazes de desenvolver substâncias chamadas metabólitos secundários,amplamente estudadas como uma forma alternativa de controle de pragas. Assim, o objetivo deste trabalho foi avaliar o potencial inseticida de dois extratos de Musa acuminata, no controle de Atta sexdens rubropilosa. Os extratos foram obtidos a partir do pseudocaule de M. acuminata, que foi submetido a secagem e moagem, produzindo dois extratos: etanólico (A1) e hidroalcoólico rotaevaporado (A2). Para a análise da bioatividade dos extratos, foi realizada uma aplicação tópica de um mililitro de cada extrato sobre as formigas, com o auxílio de spray, nas concentrações de: 2, 6, 10, 14, 18 e 20%, com água destilada (testemunha) aplicada ao teste, verificando-se a mortalidade e a CL50, em diferentes períodos de avaliação. Às 24 horas foi observada mortalidade de 90% na concentração de 20% para o extrato A1. A partir da concentração de 10% houve 100% de mortalidade nesse mesmo período para o extrato A2, e às 48 horas a concentração de 2% causou 100% de mortalidade. Na análise da LC50 para 24 horas obteve-se valores de 7,94 e 1,09% para o extrato etanólico e o extrato rotaevaporado respectivamente. E a CL50 apresentou diminuição nos valores apartir das 48 horas para o extrato etanólico apresentando valor de 2,29%. Assim, pode-se concluir que o extrato A2 é o mais eficiente, pois permite o menor consumo de extrato na diluição para posterior aplicação, devido à presença de potencial inseticida em baixa concentração.

Características e procedência da lenha usada na cocção no Brasil / Characteristics and procedures of firewood used in cooction in Brazil

A lenha vem sendo substituída ao longo dos anos por novas formas de energia, como o gás liquefeito de petróleo (GLP) e a eletricidade. Porém, esse combustível ainda representa uma fração significativa da matriz energética brasileira, muito embora as pesquisas referentes ao seu uso ainda sejam limitadas e regionais. O objetivo deste estudo foi realizar um levantamento da produção, consumo e características da lenha usada com a finalidade de cocção. De acordo com os resultados, em 2016, 26,5% da lenha produzida no Brasil foram empregados com fins residenciais, ou seja, em torno de 2x107 toneladas. A lenha é proveniente tanto da silvicultura, sendo o Paraná o maior produtor, quanto do extrativismo, sendo a Bahia a maior produtora. O estado que apresenta maior dependência desse combustível para a cocção é o Pará, enquanto o Rio de Janeiro, praticamente, não a usa para esse fim. O consumo per capita varia muito de uma região a outra do país. Com base nos dados de 2016, foi estimado um consumo de 1,7 kg/pessoa/dia. No entanto, estudos in loco mostraram variação de 0,7 a 8,5 kg/pessoa/dia. O levantamento aponta que uma parte considerável da lenha é proveniente de matas nativas que têm reflexos no desmatamento de uma dada região. A pouca disponibilidade de dados e a variação entre eles impede uma avaliação mais precisa do uso deste combustível no país e suas implicações para a saúde das florestas. A implantação de políticas públicas deveria ser prioridade do governo, pois o uso da lenha de forma inadequada afeta o manejo da vegetação nativa, além de ser uma questão socioambiental, econômica e de saúde pública.

Firewood has been replaced over the years by new forms of energy, such as liquefied petroleum gas (LPG) and electricity. However, this fuel still accounts for a significant fraction of the Brazilian energy matrix. Research regarding its use remains limited and regional in the country. The objective of this study was survey the production, consumption and characteristics of firewood used for cooking. According to the results, in 2016 26.5% of the firewood produced in Brazil was used for residential purposes, around 2×107 metric tons. Firewood comes from both silviculture, Paraná being the largest producer, and extractivism, Bahia being the largest producer. Pará presented the greatest dependence of this fuel, while Rio de Janeiro practically does not use it for this purpose. Per capita consumption varies from one region to another. Based on data from 2016, it was estimated that consumption was 1.7 kg/person/day. In situ studies showed consumption ranges from 0.7 to 8.5 kg/person/day. The study shows an obvious reliance on native forests to obtain firewood, resulting in deforestation in some areas. The low availability of data and the variation among them prevents a better assessment of the use of this fuel in Brazil and the implications for forest health. The im-plementation of public policies should be a priority of the government, as the improper use of firewood negatively affects the management of native vegetation, as well as being a socio-environmental, economic and public health burden.

Spatial dependency and correlation of properties of soil cultivated with oil palm, Elaeis guineensis, in agroforestry systems in the eastern Brazilian Amazon / Dependência espacial e correlação das propriedades do solo cultivado com dendezeiro, Elaeis guineensis, em sistemas agroflorestais na Amazônia Oriental

Geostatistics is a tool that can be used to produce maps with the distribution of nutrients essential for the development of plants. Therefore, the present study aimed to analyze the spatial variation in chemical attributes of soils under oil palm cultivation in agroforestry systems in the eastern Brazilian Amazon, and their spatial dependence pattern. Sixty spatially standardized and georeferenced soil samples were collected at each of three sampling sites (DU1, DU2, and DU3) at 0-20 cm depth. Evaluated soil chemical attributes were pH, Al3+, H+Al, K+, Ca2+, Mg2+, cation exchange capacity (CEC), P, and organic matter (OM). The spatial dependence of these variables was evaluated with a semivariogram analysis, adjusting three theoretical models (spherical, exponential, and Gaussian). Following analysis for spatial dependence structure, ordinary kriging was used to estimate the value of each attribute at non-sampled sites. Spatial correlation among the attributes was tested using cokriging of data spatial distribution. All variables showed spatial dependence, with the exception of pH, in one sampling site (DU3). Highest K+, Ca2+, Mg2+, and OM levels were found in the lower region of two sampling sites (DU1 and DU2). Highest levels of Al3+ and H+Al levels were observed in the lower region of sampling site DU3. Some variables were correlated, therefore cokriging proved to be efficient in estimating primary variables as a function of secondary variables. The evaluated attributes showed spatial dependence and correlation, indicating that geostatistics may contribute to the effective management of agroforestry systems with oil palm in the Amazon region.

A geoestatística é uma ferramenta utilizada para produzir mapas de distribuição de nutrientes essenciais para o desenvolvimento das plantas. O presente estudo teve como objetivo analisar a variação espacial dos atributos químicos do solo sob cultivo de dendê em sistemas agroflorestais na Amazônia Oriental brasileira, e seu padrão de dependência espacial. Sessenta amostras de solo espacialmente padronizadas e georreferenciadas foram coletadas em cada um de três locais de amostragem (UD1, UD2 e UD3), na profundidade de 0-20 cm. Os atributos químicos do solo avaliados foram: pH, Al3+, H+Al, K+, Ca2+, Mg2+, capacidade de troca catiônica do solo (CTC), P e matéria orgânica (MO). A dependência espacial dos atributos foi avaliada com análise semivariográfica, ajustando-se três modelos teóricos (esférico, exponencial e gaussiano). Após a análise de dependência espacial, a krigagem ordinária foi empregada para estimar os valores de cada atributo em locais não amostrados. A correlação espacial entre os atributos foi testada utilizando a cokrigagem para espacialização dos dados. Todas as variáveis mostraram dependência espacial, exceto pH em UD3. Os maiores teores de K+, Ca2+, Mg2+ e MO foram encontrados na região mais baixa da paisagem, em UD1 e UD2. Os maiores teores de Al3+ e H+Al foram observados na região mais baixa da paisagem, em UD3. Algumas variáveis foram correlacionadas, portanto a cokrigagem mostrou-se eficiente na estimativa das variáveis primárias em função das secundárias. Os atributos avaliados mostraram dependência e correlação espacial, indicando que a geoestatística pode contribuir para o manejo efetivo de sistemas agroflorestais com dendê na região amazônica.

Condiciones laborales, riesgo y salud de los trabajadores forestales de Misiones, Corrientes y Entre Ríos (Argentina), 2010-2014 / Labor conditions, risk and health of forestry workers in Misiones, Corrientes and Entre Ríos (Argentina), 2010-2014

RESUMEN En la Argentina, en las últimas décadas, la actividad forestal ha evidenciado una importante expansión promovida por el Estado a través de incentivos que alentaron la implantación de especies forestales. En este artículo se examinan las condiciones laborales de un número de trabajadores forestales de las tres principales provincias productoras de madera de la Argentina (Corrientes, Misiones y Entre Ríos). Con los datos de la Encuesta sobre Empleo, Protección Social y Condiciones de Trabajo de los Asalariados Agrarios se efectuó un procesamiento y análisis de la información referida a los trabajadores forestales de las provincias mencionadas (n=113). A su vez, la realización de entrevistas en profundidad a trabajadores (n=30) y contratistas forestales (n=8), entre 2010 y 2014, contribuyó a explicar el fenómeno estudiado en su totalidad. Los resultados obtenidos muestran que más del 50% de los trabajadores considera estar expuesto a condiciones desfavorables del medio ambiente físico de trabajo. El 16% ha tenido un accidente laboral en el último año. La alta precariedad de este tipo de empleo, sumada a las formas de contratación (tercerización), dificulta la identificación de acciones a seguir para revertir los procesos analizados.

ABSTRACT In the last decades in Argentina, forestry activity has seen an important expansion, promoted by the State through incentives encouraging the implantation of forest species. This article examines the working conditions of a number of forestry workers in the three main timber producing provinces of Argentina (Corrientes, Misiones and Entre Ríos). Using data from the Survey on Employment, Social Protection and Labor Conditions of Salaried Agricultural Workers, information on forest workers of the aforementioned provinces was processed and analyzed (n=113). In addition, in-depth interviews with workers (n=30) and forest contractors (n=8), carried out from 2010-2014, contributed to the explanation of the studied phenomenon as a whole. The results show that more than 50% of workers consider themselves exposed to unfavorable conditions in the physical working environment, with 16% having had a work accident in the last year. The high precariousness of this type of employment, in conjunction with the forms of contracting (outsourcing), makes it difficult to identify actions to be taken to reverse the processes analyzed.

Recurso polinífero utilizado por Apis mellifera (Himenoptera: Apidae) en un área de bosque subtropical del noroeste de Argentina / Pollen loads used by Apis mellifera (Himenoptera: Apidae) in an area of subtropical forest in Northwestern Argentina

Resumen En el noroeste de Argentina, los bosques subtropicales de las Yungas son de gran importancia por la gran diversidad vegetal. Las abejas melíferas (A. mellifera) utilizan estos recursos para su alimentación y en consecuencia como un servicio ecosistémico a través de la apicultura. La caracterización de la flora polinífera de una región permite conocer la fuente de alimento y definir la importancia de las diferentes especies vegetales para el desarrollo y mantenimiento de las colonias. El objetivo del presente trabajo es identificar la flora polinífera utilizada por A. mellifera en el sector oeste de las Yungas en Jujuy (Argentina) a través de la caracterización de sus cargas corbiculares y analizar las variaciones a lo largo de la primavera y verano de dos periodos productivos consecutivos. Para ello, se analizaron 14 muestras tomadas mensualmente a la largo de los periodos setiembre 2011 a marzo 2012 y setiembre 2012 a marzo de 2013. Las muestras se obtuvieron a través de trampas caza polen en las entradas de las colmenas y tratadas en el laboratorio según las técnicas convencionales de melisopalinología con posterior acetólisis. Se identificaron un total de 46 tipos polínicos pertenecientes a 25 familias botánicas. Las más importantes de acuerdo a los valores de índice de importancia de familia son: Euphorbiaceae (35.54), Fabaceae (26.27), Asteraceae (20.77), Vitaceae (16.14) y Myrtaceae (9.13). Asimismo, los principales recursos poliníferos fueron Eucalyptus, Eupatorium, Mimosa, Parapiptadenia excelsa, Sebastiania, Viguiera, Zanthoxylum, tipo Cissus y representantes de las familias Cactaceae y Euphorbiaceae. Las variaciones del índice de amplitud de nicho trófico evidencian para la zona una selección de recursos florales, donde se destaca la utilización de especies nativas. La información generada en este estudio, aporta al conocimiento del recurso ofrecido por el bosque y las especies que son de importancia para la producción apícola. Además, de contribuir a potenciar la producción y comercialización de este producto a partir de su valor agregado, permitiendo a los apicultores un buen manejo de las colmenas.

Abstract In Northwest Argentina, Yungas subtropical forests are very important because of their huge vegetal diversity. Honeybees (A. mellifera) use these resources to feed and therefore as an ecosystemic service through beekeeping. The characterization of pollen flora of a region allows getting to know the food source and defining the importance of different plant species for colonies development and maintenance. The aim of the present study is to identify the pollen flora used by A. mellifera in the Yungas Western area in Jujuy (Argentina) by means of their pollen loads characterization and to analyze the variations of two consecutive productive periods throughout spring and summer. To do this, 14 samples taken monthly were analyzed over the periods from September 2011 to March 2012 and September 2012 to March 2013. The samples were obtained from pollen traps at the entrances of the hives and were treated in the laboratory under conventional melisopalinology techniques with subsequent acetolysis. A total of 46 pollen types belonging to 25 botanical families were identified. The most important ones according to the family importance index are Euphorbiaceae (35.54), Fabaceae (26.27), Asteraceae (20.77), Vitaceae (16.14), Myrtaceae (9.13). Zanthoxylum, Sebastiania, Mimosa, Euphorbiaceae, Cactaceae, Parapiptadenia excelsa, Eupatorium, Cissus, Eucalyptus y Viguiera were identified as dominant resources. The variations of the breadth Index trophic niche show a floral resources selection for the area, where the use of native species stands out. The information produced in this study contributes to the knowledge of the resource offered by the forest and the species that are important for beekeeping production. Besides, it contributes to enhance the production and marketing of this product from its added value, allowing beekeepers a good management of hives. Rev. Biol. Trop. 66(3): 1182-1196. Epub 2018 September 01.

Spatial patterns and interactions of dominant tree species in an Amazon tropical rainforest / Patrones e interacciones espaciales de especies arbóreas dominantes en un bosque tropical en la Amazonia

Abstract Knowledge of spatial patterns and interactions of tree species allows for understanding the ecological processes of spatiotemporal structures of tropical forests, becoming essential for the establishment of strategies for the conservation and management of their resources in the long term. The aim of this study was to investigate the spatial patterns and interactions of Astronium lecointei, Dinizia excelsa and Peltogyne paniculata, three dominant timber tree species in the Jamari National Forest, Rondônia, Brazilian Amazon. The Kernel estimator was used aiming to verify the possible influence of first-order factors on species distributions. Inhomogeneous K-functions were applied to analyze species spatial patterns and interactions by means of second-order factors. Univariate analyses revealed different scale-dependent spatial patterns for the species. Aggregation related to ecological characteristics, such as habitat preference and dispersal limitation, was verified for A. lecointei and P. paniculata. D. excelsa presented a random spatial pattern, explained by specific features of its establishment, such as the need for clearings due to light requirements. Interspecific associations were evidenced by bivariate analyses, in which spatial attraction of species resulted from the same preference for microhabitats and the repulsion was a result of niche segregation. Rev. Biol. Trop. 66(3): 1009-1017. Epub 2018 September 01.

Resumen El conocimiento de los patrones e interacciones espaciales de las especies arbóreas permite la comprensión de los procesos ecológicos de estructuración espacio-temporal de los bosques tropicales, tornándose imprescindible para el establecimiento de estrategias de conservación y manejo de sus recursos a largo plazo. El objetivo de este estudio fue investigar los patrones y las interacciones espaciales de Astronium lecointei, Dinizia excelsa y Peltogyne paniculata, tres especies arbóreas madereras dominantes en la Selva Nacional del Jamari, Rondônia, Amazonia Brasileña. Para ello, se utilizó el estimador Kernel, con el objetivo de verificar la posible influencia de factores de primer orden en la distribución de las especies. Para el análisis de los patrones e interacciones espaciales de las especies por medio de los factores de segundo orden, se empleó la función K no homogénea. Los análisis univariados revelaron diferentes patrones espaciales dependientes de la escala para las especies. Agregación relacionada a características ecológicas, como preferencia de hábitat y limitación de la dispersión, fue constatada para A. lecointei y P. paniculata. Dinizia excelsa presentó un patrón espacial aleatorio, explicado por características particulares de su establecimiento, como la necesidad de claros debido a sus requisitos lumínicos. Las asociaciones interespecíficas fueron evidenciadas por los análisis bivariados, en que la atracción espacial de las especies resultó de la misma preferencia por micro hábitats y la repulsión fue resultado de la segregación de nichos.