Crescimento e eficiência do uso da água de plantas jovens de castanheira-da-amazônia em área degradada e submetidas à adubação

This work objectives to analyze the absolute growth rate (AGR), leaf gas exchange and leaf water potential (ΨW) of young Brazil nut (Bertholletia excelsa Humb. & Bonpl.) plants subjected to chemical and green fertilization treatments, compared with treatment without fertilization, aiming the restoration of a degraded area in central of Amazonia rain forest. The applied treatments were: control (without fertilization), chemical (Ouromag®) and green fertilization (fragments of branches and leaves). The diameter and height AGR in the treatment with green fertilization was about 12 times higher than the control. The ΨW reached maximum value of -0.19 MPa at noon, and minimum of -2.8 MPa at midday, both in green fertilization treatment. The intrinsic water-use efficiency (WIUE) did not differed significantly between the treatments, unlike the treatments with green and chemical fertilization increased the water-use efficiency (WUE) up to 66 and 38%, respectively, when compared to the control. Therefore, we concluded that the fertilization treatments, especially the green one, due to improvements in the use of which provides primary resources, e.g. water, play a key role in the growth of Bertholletia excelsa plants in the young phase of forest plantations on degraded area in Amazonia

Características nutricionais de plantas jovens de Bertholletia excelsa Bonpl. sob tratamentos de fertilizacąõ em área degradada na Amazônia

Among the alternatives for reintegration of deforested areas into the productive processes, one is the reforestation. However, the low natural fertility, the nutritional impoverishment of these areas by the removal of the forest cover and soil exposure, besides the lack of knowledge about the performance of tree species makes it difficult to define the best strategy of fertilization for the establishment of forest plantations in these areas. The aim of this study was to investigate the effects of mineral and organic fertilizations on the availability of nutrients in the soil, nutritional status and photosynthetic nutrient use efficiency in Bertholletia excelsa Bonpl. under forest plantations in degraded areas. The experimental design was completely randomized, with the variables: soil chemical composition, leaf nutrient contents, photosynthesis and photosynthetic nutrient use efficiency analyzed after four years from the planting. The effects of fertilization became especially noted in the superficial layers (0-2.5 and 2.5-7.5 cm) of soil. The mineral fertilization treatment increased the availability of K, Mg and Mn, while the organic fertilization raised the C and N soil contents. B. excelsa showed a higher leaf N (15.1 g kg-1), P (2.4 g kg-1), K (5.1 g kg-1), Zn (29.9 mg kg-1) and Mn (56.6 mg kg-1) under organic fertilization. The photosynthetic rates were three times higher in plants under organic fertilization compared to the control. The fertilization treatments improved the photosynthetic efficiency use of all nutrients, with emphasis on phosphorus use efficiency. Therefore, the higher leaf nitrogen content coupled with increased photosynthesis and phosphorus efficiency use in B. excelsa under organic fertilization represent important gains that may have contributed to the appropriate initial establishment of this species in the field

SILVICULTURAL ASPECTS OF BRAZILIAN NUT (Bertholletia excels HUMB. E BONPL.)

O presente estudo objetivou avaliar a sobrevivência e o crescimento de árvores de castanha-do-brasil (Bertholletia excelsa Humb. e Bonpl.) em plantios homogêneos a pleno sol, aos 27 anos de idade, Amazonas, Brasil. Os dados analisados foram sobrevivência, altura comercial, diâmetro à altura do peito, volume do cilindro, volume por indivíduo, área basal e incremento médio anual em altura, em diâmetro e em volume. O fuste foi qualificado como reto ou tortuoso. Os indivíduos apresentaram altura comercial média igual a 12,8 m, e elevado volume do cilindro (236,71 m3 ha-1), provavelmente devido à avançada idade do plantio. A maioria dos indivíduos apresentou fuste reto. Foram considerados baixos os valores médios de sobrevivência (69%), diâmetro à altura do peito (21,88 cm), incremento médio anual em altura (0,47 m ano-1), em diâmetro (0,81 cm ano-1) e em volume (8,77 m3 ha-1 ano-1), provavelmente devido à competição entre as árvores por recursos no pequeno espaçamento de plantio (3 m x 3 m), e a não realização de capinas e coroamentos.Palavras-chaves: Amazônia, crescimento de plantas, plantio florestal, silvicultura.This study aimed to evaluate dendrometric variables of Brazilian-nut tree (Bertholletia excelsa Humb. e Bonpl.) in homogeneous plantations under full sun, at 27 years after plantation, Amazonas, Brazil. The data analyzed were survival, commercial height, diameter at breast height, cylinder volume, volume per individual, basal area, and average annual increment in height, in diameter, and in volume. The bole quality was characterized as straight or tortuous. The individuals had commercial height equal to 12.8 m, and the cylinder volume was high (236.71 m3 h-1), due to the advanced age of planting. The majority of individuals presented straight bole. We observed low values of survival (69%), diameter at breast height (21.88 cm), average annual increment in height (0.47 m yr-1), in diameter (0.81 cm yr-1), and in volume (8.77 m3 ha-1 yr-1), probable due to competition among trees for resources in the small plant spacing (3 m x 3 m), and non-performing hoeing and crowning.Keywords: Amazon; forest plantation; plant growth; silviculture

Retranslocação de nutrientes em espécies florestais na Amazônia Brasileira

Internal retranslocation is an important mechanism for nutrient conservation in plants, which depends on different factors. However, there are little data about this subject, especially on tropical forest species. This study aimed to evaluate the macronutrient retranslocation dynamic and the influence of ecological (P: pioneer x NP: non-pioneer) and phenological (ND: non-deciduous x D: semideciduous/deciduous) characteristics on the macronutrient content of leaves of five tree species on monospecific plantations in the Brazilian Amazon: Acacia mangium Willd., Parkia decussata Ducke, Dipteryx odorata (Aublet) Willd., Jacaranda copaia (Aubl.) D. Don and Swietenia macrophylla King. Photosynthetically active green leaves and senescent leaves (leaf litter) were collected. Retranslocation was estimated through an equation proposed by Attiwill, Guthrie and Leuning (1978). The pioneer species presented higher foliar contents of N; the non-pioneer species presented higher contents of K, Ca and S; and the results were inconclusive for P and Mg. The deciduous species presented higher foliar contents of K and of P, whereas the foliar contents of N, Ca, Mg and S were virtually identical between the phenological groups. The internal retranslocation of foliar nutrients in pioneer and non-deciduous species was higher than that of nonpioneer and deciduous species. © 2016, Eduem - Editora da Universidade Estadual de Maringa. All rights reserved

Modificações na cobertura vegetal influenciam os atributos químicos do solo na Amazônia brasileira

Forest plantations may minimize the effects of deforestation in the Amazon. However, there are differences among species in terms of their influences on soil recovery. The effects of monospecific plantations of Acacia mangium, Dipteryx odorata, Jacaranda copaia, Parkia decussata,and Swietenia macrophylla, and areas of pasture and native forest on the chemical soil attributes of the Brazilian Amazon were evaluated. One bulked soil sample was collected per plot (0.00-0.05, 0.05-0.10, and 0.10-0.30 m; three plots of 128 m2) in each area. No significant differences in most of the soil attributes were observed among the forest plantations. However, soil K+ and P were higher in the Swietenia macrophylla plantations, while higher values of Ca2+, sum of bases, and pH occurred in Jacaranda copaia plantations. In the native forest, the pH, and P content were lower, whereas the soil organic matter (SOM) content, soil organic carbon (SOC) content, cation exchange capacity (CEC), N content, H+Al content, and Al3+ content were higher than in the plantations. The lowest values of SOM, SOC, CEC, K+, Mg2+, N, H+Al, and Al3+ occurred in the pasture. None of the forest species led to the return of the original soil chemical attributes of the native forest. However, S. macrophylla and J. copaia plantations presented the highest positive edaphic influences. © 2017, Eduem - Editora da Universidade Estadual de Maringa. All rights reserved

Ecofunctional traits and biomass production in leguminous tree species under fertilization treatments during forest restoration in Amazonia

Background: Choosing the correct species and fertilization treatments is a determining factor in the success of forest restoration. Methods: A field study was conducted in a degraded area near the Balbina hydroelectric dam in Amazonas State (AM), Brazil, to evaluate two hypotheses: (i) leguminous tree species exhibit differences in growth, leaf nutrient content, and photosynthetic nutrient use efficiencies; and (ii) differences in these characteristics depend on the fertilization treatments to which the species have been subjected. Dipteryx odorata, Inga edulis and Schizolobium amazonicum were subjected to the following treatments: (T1) unfertilized control; (T2) post-planting chemical fertilization; (T3) post-planting organic fertilization and (T4) combined chemical and organic post-planting fertilization. Results: In general, I. edulis had the highest absolute growth rate of biomass under all of the fertilization treatments. I. edulis and S. amazonicum showed the highest growth rates under the T4 treatment. D. odorata showed the greatest responses under the T2 and T4 treatments. Native leguminous trees with higher photosynthetic performance and better nutrient use efficiency exhibited greater growth and biomass production. Conclusion: The results suggest that an adequate balance between leguminous species selection and fertilization will aid in the success of forest restoration in Amazonia. © 2016 by the authors

Biomass and nutrients in three species of Parkia plantings on degraded area in Central Amazon

AbstractBiomass and nutrients partitioning strategies in tree species may reflect their ability to survive in plantations on degraded areas. The objective of this study was to investigate the content of biomass and nutrients in tree components of Parkia multijuga, Parkia nitida and Parkia pendula on plantings in degraded area in Manaus, AM. The biomass was determined by the harvest method in six trees of each species, which were subdivided into leaves, fine branches (Ø Ca > K > Mg > P. Parkia multijuga, by adopting better strategies of distribution of biomass and nutrients, it is a recommended species for reforestation programs on degraded sites in the Amazon.Keywords: Native forest species; forest nutrition; reforestation; restoration.As estratégias de distribuição de biomassa e nutrientes utilizadas pelas espécies florestais podem refletir sua capacidade de sobrevivência em plantios sobre áreas degradadas. O objetivo deste estudo foi quantificar os estoques de biomassa e nutrientes nos compartimentos arbóreos de Parkia multijuga, Parkia nitida e Parkia pendula em plantios sobre área degradada em Manaus, AM. A biomassa foi determinada pelo método destrutivo em seis árvores de cada espécie, que foram compartimentadas em: folhas, galhos finos (Ø Ca > K > Mg > P. O fato de Parkia multijuga adotar estratégias de alocação de biomassa e nutrientes que favorecerão seu desempenho sobre sítios com baixa disponibilidade de recursos sustenta sua indicação para a composição de programas de reflorestamento em áreas degradadas na Amazônia.Palavras-chave: Espécies florestais nativas; nutrição florestal; reflorestamento; restauração. AbstractBiomass and nutrients in three species of Parkia plantings on degraded area in Central Amazon. Biomass and nutrients partitioning strategies in tree species may reflect their ability to survive in plantations on degraded areas. The objective of this study was to investigate the content of biomass and nutrients in tree components of Parkia multijuga, Parkia nitida and Parkia pendula on plantings in degraded area in Manaus, AM. The biomass was determined by the harvest method in six trees of each species, which were subdivided into leaves, fine branches (Ø Ca > K > Mg > P. Parkia multijuga, by adopting better strategies of distribution of biomass and nutrients, it is a recommended species for reforestation programs on degraded sites in the Amazon.Keywords: Native forest species; forest nutrition; reforestation; restoration

Low-cost GNSS technology for monitoring grazing sheep

Extensive livestock production is supported by natural and biodiverse pastures, characterized by marked seasonal variation of biomass, plant species and growth stage. The use of the food resources and the occupation of grazing space can be very heterogeneous in such conditions due to ruminants grazing behaviour. Successful grazing and pasture management requires an understanding of the adjustment mechanisms behind the grazing behaviour that enables adaptation to grazing conditions. Use of GNSS technology allows a quick and effective grazing data collection which is, however expensive, limiting its application to research purposes. This paper reviews the principles for the application of GNSS technology and evaluates the use of inexpensive commercial GNSS receivers (commercial of the shelf - COTS: CatTrackTM”). Six receivers were used for six data collection period over two months of continuous grazing on a natural pasture. The measured static and dynamic accuracy of the receivers is 14m and 40m, respectively. The precision was 3m and the reliability 80%. The tested equipment allows the differentiation between animal activities (grazing, resting and transit). It also determines sheep locations, allowing the characterization of patterns, pathways and preferred areas. It is concluded that the COTS equipment has a high quality / price ratio, so it can become an important support decision tool essential to a more precise pasture management

Livro Verde dos Montados

O Livro Verde dos Montados apresenta diversos objectivos que se interligam: Em primeiro lugar, o Livro Verde pretende reunir e sistematizar, de uma forma simples e acessível ao público, o conhecimento produzido em Portugal pelos investigadores e técnicos de várias instituições de investigação ou de gestão que estudam o Montado. Assume-se como uma oportunidade de caracterizar o sistema tendo em conta as suas várias dimensões, identificando as principais ameaças à sua preservação assim como os caminhos que podem ajudar à sua sustentabilidade. Não sendo um documento científico, baseia-se no conhecimento científico e pretende constituir a base para uma plataforma de organização, tanto dos investigadores como do conhecimento científico actualmente produzido em Portugal sobre o Montado.Em segundo lugar, o Livro Verde deverá contribuir para um entendimento partilhado do que é o Montado, por parte do público, de técnicos e de especialistas, conduzindo a uma classificação mais clara do que pode ser considerado Montado e de quais os tipos distintos de Montados que podem ser identificados. Em terceiro lugar, o Livro Verde estabelece as bases para uma estratégia coordenada de disponibilização de informação sobre o sistema Montado, visando o seu conhecimento, apreciação e valorização pela sociedade portuguesa no seu conjunto. Deste modo, o Livro Verde poderá constituir um instrumento congregador e inspirador para a realização de acções de sensibilização e informação sobre o Montado. Em quarto lugar, pretende-se que o Livro Verde contribua para um maior reconhecimento e valorização do Montado como sistema, a nível do desenho das políticas nacionais por parte dos vários sectores envolvidos.Finalmente, o Livro Verde constituirá um documento parceiro do Livro Verde das Dehesas, produzido em Espanha em 2010, de forma a reforçar o reconhecimento e a devida valorização destes sistemas silvo-pastoris no desenho das estratégias e políticas relevantes pelas instituições europeias. Em suma, os autores pretendem que o Livro Verde dos Montados se afirme como o primeiro passo para uma efectiva definição e implementação de uma estratégia nacional para os Montados