Marcos Vinicius Winckler Caldeira

Eficiência do uso de micronutrientes e sódio em três procedências de acácia-negra (Acacia mearnsii De Wild.)

Objetivou-se avaliar a eficiencia nutricional de micronutrientes (Mn, B, Cu, Zn e Fe) e Na nos diferentes componentes das arvores de tres procedencias de acacia-negra (Acacia mearnsii), com 2,4 anos de idade, plantadas em Butia-RS (Brasil). As procedencias selecionadas foram Lake George, Bodalla e Batemans Bay. Constatou-se grande variacao na eficiencia nutricional entre as procedencias. A Lake George, alem de acumular maior biomassa total, foi tambem a mais eficiente na utilizacao dos nutrientes na producao de biomassa total das arvores. No entanto, a Bodalla mostrou ser a procedencia mais eficiente no uso dos nutrientes para producao de biomassa da casca e da madeira.

Quantificação da biomassa acima do solo de Acacia mearnsii De Wild., procedência Batemans Bay - Austrália.

The above-ground biomass of the Australian provenance Batemans Bay of black wattle ( Acacia mearnsii De Wild.), at 2.4 years after planting was quantified. The provenance was established in soils of low fertility, with high acidity, at Fazenda Menezes, District of Capao Comprido, County of Butia/RS. Nine trees were selected to form a sample. The destructive sampling comprised the individualization of the compartments of the above-ground biomass (leaves, live branches, dead branches, bark, and wood), and the determination of the dry matter allocated in each of these compartments. The production of above-ground biomass of the Australian provenance Batemans Bay was 36,1 Mg ha -1 with the following distribution: 20% in the leaves; 19,5% in the live branches; 2,8% in the dead branches; 11,8% in the bark and 45,9% in the wood.

Concentração e redistribuição de nutrientes nas folhas e no folhedo em um povoamento de Acacia mearnsii De Wild. no Rio Grande do Sul.

This work aimed to study the concentration and the redistribution of mineral nutrients in the newly mature leaves and in the litter, in a three years old Acacia mearnsii De Wild. forest, planted in soils with low fertility in Rio Grande do Sul State. Among the mineral elements analysed nitrogen had higher concentration in the newly mature leaves as well in the litter. Phosphorus and potassium were the nutrients more retranslocated. However, calcium was the element that presents had the smaller retranslocation.

Efeito de fungos micorrízicos arbusculares no desenvolvimento de duas leguminosas arbóreas.

In a green house at the National Center of Research of Agrobiology (CNPAB/EMBRAPA), the effect of the inoculation of Arbuscular Micorrhizal Fungi (AMF) in the production of Peltogyne venosa a nd Sclerolobium paniculatum was evaluated. The experimental design was completely randomized with 4 treatments ( Glomus clarum Nicolson & Schenk, Gigaspora margarita Becke Hall, native mycorrhizae and controls - without inoculation) and 25 repetitions. One hundred sixty eight days after seed germination, it was observed that the treatments did not affect seedling growth, except for P. venosa inoculated with G. margarita , which had a larger production of dry weight of fine roots. Seedlings of P. venosa and S. paniculatum inoculated with G. clarum and native mycorrhizae had the largest percentages of micorrhizal colonization. In both species studied, the largest survival percentages was of seedlings inoculated with native mycorrhizae.

Crescimento de leguminosas arbóreas em respostas a inoculação com fungos micorrízicos arbusculares.

The present study aimed at evaluating the development of inoculated or noninoculated seedlings with mycorrhizal fungi. The experimental design used was completely randomized, with 4 treatments and 25 replacements. The treatments were: Glomus clarum (Nicolson & Schenk), Gigaspora margarita (Becker & Hall), Native Fungi and Control (without inoculation). There was no statistical difference for height, diameter, aerial and subterranean phytomasses of thick roots in Copaifera martii seedlings. The highest length percentage of colonized thin roots and the survival rate were obtained in inoculated seedlings with G. margarita and G. clarum . Concerning the seedlings of Dimorphandra macrostachya, there was no statistical difference for height, diameter, aerial and subterranean phytomasses of thick or thin roots. The inoculation with G. margarita favored the percentage of mycorrhizal colonization of thin roots and survival rate in Dimorphandra macrostachya seedlings .

Crescimento de Mudas de Ateleia glazioviana em Substratos Contendo Diferentes Materiais Orgânicos / Growth of Ateleia glazioviana Seedlings in Substrates Containing Different Organic Materials

Substrates play an important role in the production of quality seedlings, because they need to present appropriate physical and chemical conditions for plant development. In this context, some organic materials have been used in the composition of substrates for seedling production. This study aimed to analyze the use of substrates with organic materials compared with substrates containing only mineral fertilizers on the growth of Timbo (Ateleia glazioviana Baill) seedlings. To this end, 11 treatments were tested, varying the composition of substrates with the mixture of different proportions of organic materials: sewage sludge, cattle manure and commercial substrate, and also only with application of chemical fertilizers. These treatments were arranged in a completely randomized design with four replications and three seedlings per replication. Based on the results observed, we recommend the addition of cattle manure with at least 20% volume to the substrate composition for the production of Ateleia glazioviana seedlings.

Micronutrientes na copa e suas correlações com o crescimento da Araucaria angustifolia (BERTOL.) O. KTZE plantada em Passo Fundo, RS

O presente trabalho foi realizado em povoamentos de Araucaria angustifolia, aos 29 anos de idade, plantados na Floresta Nacional de Passo Fundo, RS (FLONA/Passo Fundo, RS). Os objetivos foram: analisar a concentracao dos nutrientes na copa, bem como correlacionar os parâmetros de crescimento com a concentracao dos nutrientes nas folhas de A. angustifolia. Para o presente estudo, foram utilizados dois talhoes com 4,4 e 6,8 ha, respectivamente. Em cada talhao foram selecionados quatro sitios, com diferentes crescimentos, baseado na altura dominante do povoamento. Por meio do diâmetro medio de cada sitio, foram selecionadas quatro arvores por sitio, com altura similar a altura dominante do local. Nas quatro arvores selecionadas, em cada verticilo, na orientacao norte, foram coletadas folhas do ultimo periodo de crescimento para analise nutricional. Para fazer a correlacao da concentracao dos nutrientes nas folhas, foram utilizados os seguintes parâmetros de crescimento: altura total; incremento periodico anual nos ultimos cinco anos (IPA, 24-25) e o incremento corrente anual do ultimo ano (ICA). As maiores concentracoes de B foram observadas nos verticilos superiores, porem, as maiores concentracoes de Mn e Zn nos verticilos inferiores. Foi observado que o aumento nas concentracoes de Cu e B, nas folhas, esta associado as maiores alturas das arvores. As melhores correlacoes sao apresentadas pelas concentracoes de Cu e B nas folhas. As relacoes entre suas concentracoes na copa, altura total e incremento periodico anual, sao positivas, mas nao apresentam significância em relacao ao incremento corrente anual.

Ecological and Environmental Aspects of Nutrient Cycling in the Atlantic Forest, Brazil

In developing countries, where population growth is on the rise, intense anthropogenic actions in natural forests are observed usually in the form of burnings and shallow cuts. With aiming to deploy crops or even promote irrational exploitation of forest products. In this context, preservation of natural forests (tropical and subtropical forests) depends on the knowledge of their dynamics. This information is important to allow exploration of natural forests sustainably or to subsidize conservation actions. In planted and native forests, the biogeochemical cycling of nutrients predominantly occurs through production and decomposition of litterfall. The information provided in this chapter, in particular with regard to nutrient cycling, is an important basis for understanding the structure and dynamics of nutrients in the ecosystem. We characterized nutrient stocks and elucidate some aspects of forest growth and productivity. This information is important to enhance biodiversity conservation and generate ecosystem goods and services in the Atlantic Forest Biome. Even with the intense change of land use (from forest to agricultural, pasture and urbanization), the region has high diversity of endemic species, and is considered a priority area for biodiversity conservation.

Comportamento de mudas de leguminosas arbóreas inoculadas com fungos micorrízicos arbusculares.

The effect of the inoculation of arbuscular mycorrhizal fungi on the growth of two legume trees ( Cassia leiandra and Chamaecrista desvauxii ) was evaluated. The experimental design was completely randomized with four treatments and twenty-five repetitions. The treatments were: Glomus clarum (Nicolson & Schenk), Gigaspora margarita (Becker & Hall), Native Fungi and Control (without inoculation). The seedlings were cultivated in a substratum composed of compost, clay, sand and natural phosphate in the proportion of 6:2:1:1. One Hundred and sixty eight days after seed germination, stem diameter, height, above-ground biomass, below-ground biomass of thick and fine roots, and percent mycorrhizal colonization were evaluated. Although the roots of Chamaecrista desvauxii were colonized with Gigaspora margarita there was no effect of the inoculation on any of the variables measured. Seedlings of Cassia leiandra were colonized by all mycorrhizal fungy, however, there was an increase in the above-ground biomass and below-ground biomass of fine roots only on the seedlings inoculated with Glomus clarum .