Cobertura vegetal, biomassa aérea e teor de proteína do estrato herbáceo de ambiente savânico no município de Maracanã, Pará, Brasil

Low nutrient content found in natural grasslands does not meet the nutritional requirements of cattle, and this turns out to be one of the main reasons for low yield of cattle farming in savannah environments. In this context, this study evaluates vegetation cover, biomass and protein content of herbaceous plants of a savannah environment in the eastern Amazon region to explore its potential as pasture during the annual cycle. The study area was a savannah enclave (2.500 ha) in Maracanã district, Pará, Brazil. Four plots of 10 × 100 m were inventoried in four-month intervals during two years. Within each plot, biomass was determined by harvesting above-ground parts of plants from five sub-plots of 1 m2, yielding a total of 20 samples per campaign. The biomass was sorted into three categories: 1. Axonopus polydactylus; 2. Axonopus aureus; 3. other species. Within each plot, the above-ground parts were harvested and the sampled material was oven-dried, weighted and its protein content determined. The Poaceae family accounted to 63 % of the total vegetation cover, being mainly represented by the species Axonopus polydactylus and Axonopus aureus. The biomass and protein content varied with season, yielding highest values during the rainy season and lower values during the dry season. The vegetation analysed is not recommended for use as pasture for extensive cattle farming, as biomass production and protein content stayed below the required minimum values for cattle nutrition.Os baixos teores de nutrientes presentes nos campos naturais não satisfazem os necessários para a nutrição animal e isso se torna uma das principais causas do baixo desempenho da pecuária em áreas de savana. Desta maneira este estudo teve como avaliar a cobertura vegetal, a biomassa e o teor de proteína de plantas herbáceas em uma savana na Amazônia Oriental, a fim de avaliar seu potencial como pasto ao longo do ano. A área de estudo foi um enclave de savana (2.500 ha) em Maracanã, Pará, Brasil. Quatro parcelas de 10 × 100 m foram inventariadas em intervalos trimestrais, durante dois anos. Dentro de cada parcela, a biomassa foi determinada pela colheita das partes acima do solo em cinco sub-parcelas de 1 m2., totalizando 20 amostragens por coleta. A biomassa foi classificada em três categorias: 1. Axonopus polydactylus; 2. Axonopus aureus; 3. Outras espécies. Dentro de cada parcela, foram coletadas as partes aéreas e o material amostrado foi seco em estufa, moído, tendo seu teor de proteína total determinado. A família Poaceae contribuiu com 63% da cobertura total, representado principalmente pelas espécies Axonopus polydactylus e Axonopus aureus. A biomassa e o teor de proteína variaram com a estação, apresentando os maiores valores durante a estação chuvosa e os inferiores na estação seca. A vegetação analisada não é recomendada para uso como pastagem em pecuária extensiva, pois a produção de biomassa e teor de proteína foram inferiores aos valores mínimos exigidos pela nutrição animal

Revues reçues

O recurso polínico coletado por operárias de Melipona seminigra merrillae Cockerell, Melipona fulva Lepeletier, Trigona fulviventris (Smith) e CephaloTrigona femorata Guérin, no Campus da UFAM, Manaus (AM) foi estudado no período de março a outubro de 2001. Noventa tipos polínicos foram coletados pelas abelhas, distribuídos em 31 famílias, 67 gêneros e 10 formas Tipo. Trigona fulviventris diversificou mais suas coletas, utilizando 58 fontes no período. O tamanho do nicho polínico utilizado pelas abelhas ficou assim distribuído: T. fulviventris (58), M.s. merrillae (41), C. femorata (34) e M. fulva (25). Dos tipos determinados, os que mais contribuíram para a dieta das abelhas, apresentando as maiores freqüências nas amostras de pólen, foram Miconia myriantha (12,91%), Leucaena leucocephala (9,52%), Tapirira guianensis (6,53%), Eugenia stipitata (6,22%), Protium heptaphyllum (6,17%) e Vismia guianensis (5,93%). As abelhas de modo geral concentraram suas coletas em um número reduzido de espécies vegetais e com um grau diferenciado de uso para cada uma das fontes. Tipos polínicos com freqüência acima de 10% ocorreram em pequena proporção na maioria dos meses, sendo responsáveis por mais de 50% do total do pólen coletado em cada mês. A utilização das fontes de pólen variou conforme a espécie. T. fulviventris teve uma dieta mais ampla e diversificada, enquanto M. fulva foi a que menos diversificou suas coletas. T. fulviventris apresentou maior uniformidade no uso das fontes polínicas e a sobreposição de nichos polínicos foi maior entre M.s. merrillae e M. fulva e menor entre T. fulviventris e C. femorata.The objective of this study was to characterize the resources used by Amazonian bees Melipona seminigra merrillae, Melipona fulva, Trigona fulviventris and CephaloTrigona femorata, in an urban Forest patch at Manaus city from March to October 2001. The pollen analysis determined 90 pollen types, distributed in 31 families, 67 genera and 10 palynologycal types unidentified. Trigona fulviventris was the bee species that presented the most diversified pollen types, using 58 sources in that period. The size of pollen types used were distributed as follows: T. fulviventris (58), M.s. merrilae (41), C. femorata (34) and M. fulva (25). Plant species contributing the most for the diet of the bees and presenting the highest frequencies on the pollen samples were Miconia myriantha (12,91%), Leucaena leucocephalla (9,52%), Tapirira guianensis (6,53%), Eugenia stipitata (6,22%), Protium heptaphyllum (6,17%) and Vismia guianensis (5,93%). Generally the bees concentrated their collections on a reduced number of plant species and with a differentiated degree of use for each source. Pollen types with frequency above 10% occurred in a small proportion for most months, being responsible for more than 50% of all the pollen collected every month. Pollen source used varied according to the species, T. fulviventris had a more broad and diversified diet, whereas M. fulva was the bees species that least diversified its diet. T. fulviventris presented higher uniformity on the use of pollen sources and the pollen niches overlap was higher between M.s. merrillae and M. fulva and lower between T. fulviventris and C. femorata

Distribuição e conservação das espécies de Aniba Aubl. (Lauraceae Jussieu) no Brasil

This study conducts a biogeographical review of Aniba in Brazil, including its actual and potential distribution, and a review on the species conservation status. The potential distribution of each Aniba species was modeled using the Brazilian Plants and Fungi Biogeography system, which is interconnected with the SpeciesLink network. A consensus model based on up to five algorithms was used to model the potential distribution of each species. The endemism, conservation status and rarity of each species in Brazil were also analyzed. A total of 3059 records of 30 Brazilian Aniba species were found. In total, 16.1% of the records were excluded because of the lack of valid names, and 53.4% were excluded because of the lack of georeference and name of the person who identified the record. The consensus model showed good results for species with 20 or more pixels. The other species had many errors, and their models could only be used to determine new areas for collections. Nine species were endemic to Brazil, and only three species showed no indicator of rarity. The geographical distribution of Brazilian Aniba species shows a predominantly Amazonian pattern. Only four species are not actually found in the Amazon. Some Amazonian species may also be found in Atlantic Forest areas, and many other species have the potential to live there. Our results indicate that only three species have no conservation problems, whereas 14 species have conservation problems, and 13 other species require further population studies to be best evaluated. © 2018, Universidade Estadual de Campinas UNICAMP. All rights reserved

COMPARISON OF DIFFERENT METHODS OF MEASURING TREE VOLUMES IN THE MUNICIPALITY OF ANAPU, PARÁ, BRAZIL

The objective of this study was to compare three methods of measuring the volume of individual trees used extensively as a basis for adjusting volumetric functions in areas under forest management in the Brazilian Amazon, and verify the influence of species and diameter classes in obtaining the volume of individual trees.   A total of 53 sample trees belonging to five species were analyzed and separated into three diametric classes.  The real volume (VR) was obtained using Smalian’s method on fixed sections of 2 meters intervals along the stem; the geometric volume (VG) was also obtained by Smalian’s method, but with the lengths of the various sections along the stem.  Volume loss (VP) was subtracted from the VR to obtain the usable volume (VA).  An ANOVA in a factorial design (5 x 3 x 3) was performed to verify the effect of 5 species, 3 diameter classes, and 3 volume measurement methods (VR, VG, and VA) on the different volumes obtained.  The 3 factors did affect the outcome of the analysis, but there were no interactions found between these variables.  The volumes obtained by cubic scaling with different lengths (VG) presented a lower mean volume than VR.  Although there was no difference between the means of VA and VR, wood loss was 6.5% of the total volume. There is a relationship between section length and volume loss, according to the presence of hollows, twists and cracks in the logs in the largest diameter classes

ESPÉCIES INDICADAS PARA A RECOMPOSIÇÃO DA FLORESTA CILIAR DA SUB-BACIA DO RIO PEIXE-BOI, PARÁ

http://dx.doi.org/10.5902/1980509815736This study aims to indicate native species to be used in the restoration of degraded riparian forests in the subwatershed of Peixe-Boi river. All trees and shrubs with diameter at breast height (DBH) > 5 cm were inventoried in ten areas of secondary forest and six areas of igapó forest. The results were analyzed by Principal Component Analysis and the silviculture of the species was assessed by literature review. In Igapó areas 66 species were found; the areas had low richness and low diversity index of Shannon, when compared with data from the secondary forests. The floristic composition was heterogeneous, and the floristic similarity is higher between areas that are closer geographically. In the secondary forests were found 175 species; the areas showed high abundance of individuals, high species richness, diversity and evenness. Secondary forests were separated according to geographic proximity and age, which is directly linked to the successional stage. The PCA analysis established the ecological importance of 29 tree species; however only ten species had enough silvicultural information. Due to a greater ecological importance and viable silvicultural techniques available in the literature, Carapa guianensis, Pachira aquatica, Spondias mombin, Tapirira guianensis and Virola guianensis are the most suitable species to restore the degraded areas, in association with Inga edulis, Jacaranda copaia, Pseudopiptadenia psilostachya, Simarouba amara and Vismia guianensis of the secondary forests, that can be planted in the borders and in the nearby areas of igapó forests.http://dx.doi.org/10.5902/1980509815736Diante da importância ecológica que as florestas ciliares representam para o equilíbrio ambiental, este estudo objetiva indicar espécies nativas para serem usadas na recomposição de florestas ciliares degradadas existentes na sub-bacia do Rio Peixe-Boi. Foram inventariadas todas as árvores e arbustos com diâmetro a 1,30 m do solo > 5 cm em dez áreas de floresta secundária e seis de floresta de igapó. Os dados foram analisados pela Análise de Componentes Principais (ACP) e as espécies avaliadas silviculturalmente através de revisão bibliográfica. As áreas de igapó tiveram baixo índice de riqueza e diversidade de Shannon, quando comparado com os dados das florestas secundárias. A composição florística dos igapós foi bem heterogênea, e há maior similaridade florística entre áreas de maior proximidade geográfica. As florestas secundárias tiveram grande abundância de indivíduos, alta riqueza, diversidade e equabilidade e foram agrupadas em função da proximidade geográfica e da idade, o que está diretamente ligado ao estádio sucessional. A análise ACP estabeleceu a importância ecológica de 29 espécies arbóreas, contudo, foram encontradas informações silviculturais de apenas dez espécies. Por apresentarem grande importância ecológica e técnicas silviculturais viáveis e disponíveis na literatura, as espécies de igapó Carapa guianensis, Pachira aquatica, Spondias mombin, Tapirira guianensis e Virola guianensis são as mais indicadas para a recomposição dessas áreas, em associação com as espécies Inga edulis, Jacaranda copaia, Pseudopiptadenia psilostachya, Simarouba amara e Vismia guianensis de floresta secundária, que podem ser plantadas nas áreas de bordas e adjacentes às florestas de igapó

Flora and structure of the secondary vegetation after the use of different crushers

O objetivo deste trabalho foi caracterizar e comparar a estrutura de florestas secundárias, com quatro anos de idade, no nordeste do Pará, que foram formadas após o uso dos trituradores florestais Ahwi FM600 (T1) e Tritucap (T2). O estudo foi realizado em cinco áreas de pequenos produtores, cada uma dividida em parcelas que totalizavam 60 m2 por área de estudo. Foi encontrada diversidade média (H') de 2,84 para as áreas T1 e 2,95 para as T2. A densidade média foi 530.167 indivíduos ha-1 nas áreas T1 e 459.556 indivíduos ha-1 nas T2; a média de área basal das T1 foi 1,25 m² ha-1 e a das T2, 4,55 m² ha-1; a biomassa seca estimada para as áreas T1 foi de 2,37 t ha-1 e 6,68 t ha-1 para as T2. Ocorrem diferenças estruturais nas florestas secundárias, formadas após a utilização dos trituradores.The objective of this study was to characterize and compare the structure of secondary forests with four years of age, in the northeast of Pará State, which were formed after use of the crushers Ahwi FM600 (T1) and Tritucap (T2). The study was accomplished in five areas of small producers, each one were divided in plots with 60 m² for study area. The mean diversity (H') was 2.84 for T1 areas and 2.95 for T2 areas; mean density was 530,167 ind. ha-1 in T1 and 459,556 ind. ha-1 in T2; mean basal area of T1 was 1.25 m² ha-1 and 4.55 m² ha-1 for T2; estimate dry biomass for T1 was 2.37 t ha-1 and 6.68 t ha-1 for T2. There are structural differences on secondary forests formed after the use of both crushers

COMPLEXIDADE DAS PAISAGENS DO PROJETO DE ASSENTAMENTO BENFICA, SUDESTE PARAENSE, ESTADO DO PARÁ

Este trabalho tem como principal objetivo analisar e espacializar a evolução dos estados de transformação da complexidade, de diferentes Tipos de Paisagens do Projeto de Assentamento Benfica, Mesorregião Sudeste Paraense. Foram utilizadas imagens de satélite Landsat-TM correspondentes a 1987, 1992, 1996, 2001 e 2005 e técnicas de Geoprocessamento conduzidas no sistema SPRING, além de dados de campo e modelos gráficos da paisagem. A metodologia aplicada permitiu a identificação, classificação e quantificação de seis Tipos de Paisagens: Florestal (TP0), Mosaico Agrícola (TP1), Mosaico Agrícola com Pastagem (TP2), Grandes Extensões de Pastagem (TP3), Grandes Extensões de Pasto com Babaçu (TP4) e Babaçual (TP5). A integração dos resultados deu origem a uma Escala de Complexidade dos Tipos de Paisagens, em que os graus de intensidade variaram do mais “simples” (0) ao mais “complexo” (12), sendo os de maior intensidade os Tipos de Paisagens Florestal (TP0), Mosaico Agrícola (TP1) e Mosaico Agrícola com pastagem (TP2). A abordagem geográfica refletiiu diferentes dinâmicas que se estabelecem a partir das condições e chances de manter ou não os sistemas produtivos, fazendo aumentar ou diminuir o seu grau de complexidade. O enfoque na complexidade de uma tipologia de paisagens permitiu tratar questões ligadas à sua dinâmica e mostrou ser aplicável para qualquer planejamento ou estratégia de conservação ambiental. Palavras-chave: Sudeste Paraense. Projeto de assentamento. Tipos de paisagens. Complexidade da paisagem. Complexity of settlement project landscapes in Benfica, southeastern of Pará, State Pará This work has as main objective to analyze and spot the evolution of complexity conversion of different types of landscapes in Benfica Settlement Project, southeastern region of Pará. We used images from Landsat-TM corresponding to 1987, 1992, 1996, 2001 and 2005 and geo processing techniques conducted by SPRING system, as well as field data and graphical models of landscape. Applied methodology allowed the identification, classification and quantification of six types of landscapes: Forest (TP0), Agricultural Mosaic (TP1), Mosaic of Agricultural Pasture (TP2), large areas of pasture (TP3), large areas of pasture with Babassu ( TP4) and forest of Babassu palms (TP5). Integration of results led to a range of complexity of the types of landscapes, where the degrees of intensity ranging from “simple” (0) to more “complex” (12), being the more intense the Types of Forest Landscapes (TP0), agricultural Mosaic (TP1) and Mosaic Agricultural pasture (TP2). The geographical approach reflected different dynamics that are established based on the conditions and chances of maintaining or not the production systems, thus increasing or decreasing its complexity. The focus on the complexity of a typology of landscapes allowed addressing issues related to their function and proved to be applicable to any plan or strategy for environmental conservation. Key words: Southeast of Pará. Settlement project. Types of landscapes. Complexity of the landscape

Composição florística e estrutura das plantas espontâneas das pastagens de Urochloa no norte do Amapá.

Nas pastagens, as árvores e arbustos, remanescentes da floresta original ou oriundas da chuva de sementes, fazem parte das plantas espontâneas; por um lado podem ser consideradas competidoras que enfraquecem a forrageira, por outro lado podem ser responsáveis por uma dinâmica equilibrada, inclusive diminuindo a densidade das competidoras. O objetivo deste estudo foi descrever a estrutura e composição florística das plantas espontâneas e verificar a influência da espécie forrageira e a presença de plantas lenhosas existentes acima do estrato herbáceo, além de investigar a existência ou não de infestação nas pastagens ao longo da BR-156, no município de Iapoque, estado do Amapá, Brasil. Foram amostrados 31 pastos em propriedades de pequenos agricultores familiares; esses foram categorizadas de acordo com: (1) as espécies orrageiras(Urochloa brizanthacv. Marandu e U.humidicola); (2) e a presença de plantas lenhosas (pastoslimpos ou sujos) acima do estrato herbáceo. Em cada área, o levantamento florístico foi realizado em um transecto de 1 x 50 m (50 m²), onde todos os indivíduos com 0,10 ≤ altura < 2,0 m foram inventariados. Foram encontradas 90 espécies, com predominância das herbáceas. A composição florística das plantas espontâneas é bem similar àquelas encontradas em outras pastagens da Amazônia, contudo vários pastos mostraram infestação por alguma espécie, tais como Stigmaphyllon convolvulifolium, Stigmaphyllon sinuatum, Borreria verticillata, Hyptis atrorubens,Desmodium barbatumouStachytarpheta cayennensis. A estrutura e composição florística dasplantas espontâneas não é influenciada nem pela forrageira, nem pela presença de plantas lenhosas existentes acima do estrato herbáceoIn pastures, trees and shrubs, remaining from original forest or the rain ofseeds, arepartofspontaneous plants; in this backgroundthey are consideredcompetitors thatweaken a forageor may be responsible for a balanced dynamic, decreasing the density ofcompeting plants. The aimofthis study was to describe the structure and floristic composition ofspontaneous pasture plantsand to verify the influence offorage species and the presence ofwoody plants existing above theherbaceous stratum, besides investigating the presence or not of infestation along the BR-156highway, in the municipality ofOiapoque, Amapá state, Brazil. Thirty-one pastures were sampledonsmallholder family farms; these were categorized according to: (1) the foragespeciesUrochloabrizantha cv. Marandu and U. humidicola); (2) and the presence ofwoody plants (clean or dirtypastures) above the herbaceous stratum. In each area, the floristic survey was performedin a 1 x 50m (50 m2) transect, where all individuals with 0.10 ≤ height < 2.0 m were inventoried. A total of90species were recorded, predominantly herbaceous. The floristic composition ofspontaneous plants isvery similar to those found in other pastures ofthe Amazonia, however several pastures showedinfestation by some species, such as Stigmaphyllon convolvulifolium, Stigmaphyllon sinuatum,Borreria verticillata, Hyptis atrorubens, Desmodium barbatum, or Stachytarpheta cayennensis. Thestructure andfloristic composition ofspontaneous plants is not influencedeither by forage or by thepresence ofwoody plants existingabove the herbaceous stratum

Tree Regeneration Under Different Land-Use Mosaics in the Brazilian Amazon’s “Arc of Deforestation”

We studied the tree-regeneration patterns in three distinct agricultural settlements in the Eastern Amazon to test the influence of land-use mosaics. The following questions are addressed: are the floristic structure and composition of regenerating trees affected by the various land-use types applied in the agricultural settlements? Do tree-regeneration patterns respond similarly to distinct land-use mosaics? Is there a relationship between tree regeneration and soil characteristics among the land-use types? The regeneration was inventoried at 45 sampling points in each settlement. At each sampling point, fourteen soil variables were analyzed. Nine different land-use types were considered. The floristic structure and composition of the settlements showed differences in the density of individuals and species and high species heterogeneity among the land-use types. The maximum Jaccard similarity coefficient found between land-use types was only 29 %. Shade-tolerant species were the most diverse functional group in most land-use types, including pasture and annual crops, ranging from 91 % of the number of species in the conserved and exploited forests of Travessão 338-S to 53 % in the invaded pastures of Maçaranduba. The land-use types influenced significantly the floristic structure and composition of regenerating trees in two agricultural settlements, but not in third the settlement, which had greater forest cover. This finding demonstrates that the composition of each land-use mosaic, established by different management approaches, affects regeneration patterns. Tree regeneration was related to soil characteristics in all mosaics. Preparation of the area by burning was most likely the determining factor in the differences in soil characteristics between forests and agricultural areas. © 2015, Springer Science+Business Media New York

EFECTOS DE DIFERENTES TAMAÑOS DE FRAGMENTOS FORESTALES EN LA DENSIDAD, CALIDAD DE LA COPA Y FUSIBLES DE ANDIROBA, SURESTE DE PARÁ

Em meio a uma heterogeneidade de ambiente, a fragmentação tem mostrado efeitos e interações distintas. O objetivo desse estudo é comparar a densidade, qualidade da copa e altura do fuste da espécie andiroba (Carapa guianensis Aublet) em diferentes tamanhos de fragmentos florestais, no Projeto de Assentamento Agroextrativista Praialta Piranheira, sudeste do Pará. A metodologia envolveu inventario florístico em três áreas de fragmentos grandes (> 50 hectares) e três fragmentos pequenos ( 50 hectares) and three fragments small ( 50 hectáreas) y tres fragmentos pequeños (<50 hectáreas). La densidad ind / ha, la calidad de la copa y la altura del tallo (m) se compararon entre los fragmentos mediante la prueba ANOVA - F. Los resultados muestran que no hubo diferencia estadística de las variables estudiadas en los diferentes tamaños de fragmentos de bosque, tal similitud puede ser En relación con los factores ambientales, así como con las acciones antrópicas, este trabajo sugiere que otras variables se investiguen entre ellas la acción antrópica, así como la prueba de otros tamaños de fragmentos de bosque. PALABRAS CLAVES: Agro-extractivistas, Cubierta vegetal, Producto no maderable