Western Para State Research Articles

CARACTERIZAÇÃO ENERGÉTICA DO CARVÃO VEGETAL DE Eucalyptus urophylla x Eucalyptus grandis PLANTADOS NO OESTE DO PARÁ

Há ausência de informações sobre as características energéticas do carvão de eucaliptos plantados na região Amazônica. Não há pesquisas que definam parâmetros adequados para estes novos materiais visando os principais indicadores de qualidade energética. O objetivo deste trabalho foi realizar a caracterização energética do carvão de Eucalyptus urophylla x Eucalyptus grandis proveniente de plantio na região de Monte Alegre, no oeste do estado do Pará. Foram utilizadas amostras de madeira de árvores de Eucalyptus urograndis com nove anos, carbonizadas a 500ºC e a 1,7ºC.min-1. Avaliou-se o rendimento gravimétrico em carvão, densidade aparente, poder calorífico superior e teores de carbono fixo, materiais voláteis e cinzas. Verificou-se a existência de potencial da espécie baseando-se nas características avaliadas. PALAVRAS-CHAVE: Eucalyptus urograndis, Plantios, Parâmetros de qualidade.

Breakdown of green and senescent leaves in Amazonian streams: a case study

Allochthonous organic matter in low-order streams is, in general, mainly composed of senescent leaves. However, in tropical streams green leaves can represent an important source of energy. The present study evaluated the decomposition of green and senescent leaves in Amazonian streams using leaves of three plant species: Inga stipularis D.C. 1876, Tococa guianensis Aubl. 1775 and Vochysia ferruginea Mart. 1826. The leaves were incubated for 120 days in four streams in the municipality of Santarem in western Para State, Brazil. Senescent leaves were collected using nylon nets suspended 1 m above the ground, while green leaves were collected manually, directly from the trees. Green leaves exhibited better nutritional status: higher values for nitrogen and phosphate and lower values for carbon. Toughness and percentages of tannin and lignin of the green and senescent leaves varied among the studied species. Mass loss of green leaves was ~ 3.5 times higher than that of senescent leaves after 120 days. Higher values of phosphate and nitrogen and lower values of carbon, tannin, and lignin in green leaves were fundamental in explaining the difference in decomposition between green and senescent leaves. These differences reinforce the importance of understanding the role of green leaves in aquatic environments.

Desenvolvimento inicial de espécies arbóreas em sistemas agroflorestais no Baixo Amazonas, Pará, Brasil

Estudos sobre o desenvolvimento inicial de espécies arbóreas em sistemas agroflorestais são importantes, pois fornecem subsídios para o manejo desses agroecossistemas. O objetivo dessa pesquisa foi avaliar a sobrevivência e o crescimento em altura de mudas de espécies arbóreas em sistemas agroflorestais amazônicos submetidos a diferentes formas de preparo da área e manejo. O experimento foi conduzido em dois sistemas agroflorestais (sucessional e consórcio agroflorestal) localizados no Baixo Amazonas, oeste do estado do Pará. No consórcio agroflorestal comercial, a taxa de sobrevivência das espécies não ultrapassou o valor de 70%. No sistema sucessional a taxa de sobrevivência das espécies arbóreas implantadas foi alta com a maioria variando entre 90 a 100%. O estresse hídrico nos períodos mais secos do ano é um fator limitante na adoção de sistemas agroflorestais na região causando mortalidade das mudas. Quanto ao crescimento em altura, as espécies avaliadas obtiveram desempenhos satisfatórios em ambos os sistemas.

MANEJO FLORESTAL COMUNITÁRIO EM PARCERIA NA AMAZÔNIA BRASILEIRA: O CASO DA FLONA DO TAPAJÓS

The paper discusses community forest management in the Brazilian Amazonia, particularly how partnership as theory and practice contributes to its implementation and consequently for environmental governance and local development. In this paper, partnership is taken as an important dimension of environmental governance that contributes to management of sustainable productive activities in public forests such as community forest management. The research takes as case study the Tapajos National Forest located in western Para state and also the community cooperative that carries out forest management in this forest. The research reveals that community forest management in the Tapajos National Forest started and developed from stakeholders’ networks that involve government, civil society and local communities that resulted on partnerships. These partnerships contribute to formation of forest resources collective management that in its turn has been considered an efficient and qualified process to creation of jobs and income. It also allows technical and professional training to forest dwellers. The research shows that the management pattern of the Tapajos National Forest has been considered national and internationally as a reference in forest management. It emerged as an outcome of the stakeholder networks performance in which each partner uses its own expertise to promote sustainable local development in west Para, Amazonia.

Trace gas fluxes from intensively managed rice and soybean fields across three growing seasons in the Brazilian Amazon

The emission of gases that may potentially intensify the greenhouse effect has received special attention due to their ability to raise global temperatures and possibly modify conditions for life on earth. The objectives of this study were the quantification of trace gas flux (N2O, CO2 and CH4) in soils of the lower Amazon basin that are planted with rice and soybean, and the relation of this flux to soil physical and chemical parameters and to precipitation. This study was conducted in agricultural fields planted with rice (Oryza sativa) and soybean (Glycine max), located near the cities of Belterra and Santarem in western Para State, Brazil, during the production years of 2005 to 2007. Measurements were done using static chambers in the field, and samples were analyzed by gas chromatography in the laboratory. Statistical analysis was conducted to determine variation in gas flux in both crops, and the results show that CO2 flux varied between 305 and 227 mg-C m-2 h-1 under rice, and 243 and 156 mg-C m-2 h-1 under soybean. Flux of N2O under rice varied between 4.5 and 20.4 µg-N m-2 h-1, and under soybean flux variation was between 4.0 and 9.4 µg-N m-2 h-1. Variation in flux of CH4 under rice was between 5.1 and 14.0 µg-C m-2 h-1, and under soybean it was 0.4 and 1.2 µg-C m-2 h-1. These results demonstrate that, during the study period, the rice crop had higher flux for all trace gases than the soybean crop. Key words: Amazon region, trace gas, crops.

Inventário Florestal de Grandes Áreas na Floresta Nacional do Tapajós, Pará, Amazônia, Brasil

Founded in 1974 in western Para state, federal conservation unit Tapajos National Forest, with a predominance of tropical rain forest, has been studied by the forest science for decades. In 2012, studies were performed on the floristic composition and phytosociology of forest management zone Non Timber Conservation Unit. Were launched 204 sample units of 30 m x 250 m, with 500 meters of distance between them, distributed systematically, in two areas, 94 plots in Area 1 and 110 plots in Area 2 in a sampling intensity of 0.19%. In the sample units, it was considered the following size classes: C-1 = 10 cm ≤ DBH < 25 cm subplot of 30 mx 50 m; C-2 = 25 cm ≤ DBH <50 cm subplot of 30 m x 100 m; and C-3 = DBH ≥ 50 cm in the share of 30 m x 250 m. Data were processed by stratified random sampling. Forest inventory were recorded 242 species belonging to 50 botanical families. In Area 1 were obtained 272.5 tre. ha -1 and basal area of 19.1 m². ha -1 , while in Area 2, were 176.8 tre. ha -1 and 13.7 m². ha -1 . The Forest inventory got a sampling error of less than 10%, proved to be operational and low cost, so the potential for use in other areas of forest with large areas in the Amazon. Keywords: Forest Inventory, Conservation Units; Amazon.

Searching for a Better Life: Peri‐Urban Migration in Western Para State, Brazil

The world today is an urban world. While rural to urban migration has contributed significantly to the increased urbanization of the globe, that process has not always been as clear and permanent as it appears. In this paper we report on the migration of smallholders to peri‐urban interface () zones in western Pará state, Brazil. We found that rural‐urban migrants were constrained by their lack of marketable skills and as a consequence had few job prospects and experienced a low quality of life in the cities to which they had migrated. This led them to resettle in places at the where they have the ability to supplement limited wages with more familiar subsistence activities, which reflected cultural identity and rural antecedents while enjoying a higher quality of life. The recent implementation in Brazil of a variety of conditional cash‐transfer programs has added to the attractiveness of peri‐urban places and contributes to a regional shift to livelihoods based on a combination of agriculture and extractivism supplemented by support from federal assistance programs.

Ecological and social determinants of leishmaniasis in the Legal Amazon, Brazil

Leishmaniasis is a reemerging disease of worldwide distribution and has a public health importance. It is an infectious disease, parasitical and clinical severity ranging from a healthy appearance to a severe stage. Features two major forms, such as cutaneous leishmaniasis (cutaneous and mucocutaneous) and visceral leishmaniasis. This form can be deadly for reaching the organs. The four main protozoa that cause such clinical manifestations are Leishmania chagasi , Leishmania braziliensis , Leishmania amazonensi s and Leishmania guyanensis . Environment, social and demographic factors are key for the transmission of leishmaniasis, due to its vector being a sand fly - insect with hematophagous habits - and its main reservoir are dogs. In Brazil, leishmaniasis is endemic and widely distributed. 80% of reported cases are in children under 10 years. The Legal Amazon region is an area of study of public health, having suffered anthropogenic actions that undermine the ecological balance of the site. In this area, visceral leishmaniasis is increasing in western Para state due to its economic development, which involves the public health. This study aims to relate environmental and health factors with the incidence of leishmaniasis in the Legal Amazon and this relationship will be used secondary data from publications in the National Health Information System (NHIS).