Rudi Witschoreck

Crescimento inicial de Pinus taeda L. relacionado a doses de N, P e K.

This study aimed to evaluate the effect N, P and K on the growth of young (19 month-old) Pinus taeda . The experiment took place near Cambara do Sul county, with UTM coordinates of 562125 E and 6777386 N. The statistical methodology was the confounding technique, for three factors, with four levels, totalizing 64 treatments, allocated in four blocks. The following variables were measured: total height, crown height, steam diameter and crown diameter. The results pointed out a significant linear quadratic effect for P, indicating that P fertilization is essential on the initial development of Pinus taeda plants, with a maximum cylindric volume achieved at 64 and 87 kg ha -1 doses of P 2 O 5 and K 2 O respectively.

Produção de biomassa no corte raso em plantio de Araucaria angustifolia (Bertol.) Kuntze de 27 anos de idade em Quedas do Iguaçu, PR

This study, conducted in a 27-year-old Araucaria angustifolia stand in the municipality of Quedas do Iguacu (PR) county, aimed to estimate tree components, understory and accumulated litter biomasses. Biomass was estimated through regression equation adjustments, with 21 trees felled, distributed among 7 diametric classes, and with litter and understory based on known sample unit areas. Total stand biomass was 241.92 Mg ha -1 , with 82.2% composed of Araucaria angustifolia , 9.6% composed of understory and 8.2% composed by litter. Considering only Araucaria angustifolia , the biomass was of 198.62 Mg ha -1 , composed of wood (51.5%), bark (14.7%), roots (13.0%), lives branches (11.8%), aciculated branches (6.6%) and dead branches (0.5%). Relative biomass production for the wood component may be low, when compared to other forest species, mainly due to the high allocation in the bark component.

Biomassa em povoamentos de Eucalyptus spp. de pequenas propriedades rurais em Vera Cruz, RS

The study was conducted in 2, 4, 6 and 8 year-old Eucalyptus spp. stands, in the municipality of Vera Cruz, RS. The eucalyptus biomass sampling consisted of felling 24 trees, 6 trees per age, distributed in three diametric classes. The understory and litter compartments were also sampled. The estimated biomass was 26.70; 44.55; 192.67 and 232.93 Mg ha -1 in eucalyptus; 1.87; 1.97; 4.37 and 8.24 Mg ha -1 in understory and 4,05; 5,98; 11,80 and 12,28 Mg ha -1 in the litter, totaling 32.62; 52.50; 208.84 and 253.45 Mg ha -1 , respectively, in 2, 4, 6 and 8 year stands. Except for the wood, all the other components of eucalyptus trees showed a decrease in relative biomass with the increase of age.

Biomassa e nutrientes no corte raso de um povoamento de Pinus taeda L. de 27 anos de idade em Cambará do Sul – RS

Este trabalho, realizado em um povoamento de Pinus taeda de 27 anos de idade no municipio de Cambara do Sul (RS) teve como objetivos: estimar a producao de biomassa, o estoque de nutrientes e avaliar o impacto nutricional de diferentes intensidades de remocao de biomassa com a colheita florestal. A biomassa foi estimada por meio do ajuste de equacoes de regressao, com coleta de 15 arvores distribuidas em 5 classes diametricas. O estoque de nutrientes foi obtido pelo produto entre o conteudo medio de nutrientes em cada componente da biomassa e o numero de arvores por classe diametrica por hectare. A biomassa de Pinus taeda, acima do solo, foi estimada em 266,08 Mg ha-1, sendo composta por: 69,1 % de madeira do tronco, 17,1 % de galhos vivos, 6,7 % de casca do tronco, 3,8 % de galhos secos e 3,4 % de aciculas. O estoque de nutrientes na biomassa, em kg ha-1, foi estimado em: 511,96 de N; 44,39 de P; 174,27 de K; 310,77 de Ca; 103,80 de Mg; 115,36 de S; 2,94 de B; 0,62 de Cu; 17,34 de Fe; 36,70 de Mn e 4,46 de Zn. A distribuicao relativa do estoque total de nutrientes nos componentes da biomassa de Pinus taeda apresentou a seguinte sequencia: madeira do tronco (43,6 %), galhos vivos (24,8 %), aciculas (19,0 %), casca do tronco (8,7 %) e galhos secos (3,9 %). A colheita de toda biomassa acima do solo, quando comparada com a retirada apenas da madeira do tronco, acarreta uma elevacao na exportacao de nutrientes que pode variar de 58,0 % a 127,4 %, dependendo do nutriente, enquanto a remocao de biomassa aumentou 40,8 %.

Limites de precaução e de controle em análises nutricionais de espécies florestais

The paper had as its objective to estimate the precaution limits and control for macro and micro nutrients, present in different components of the biomass, of Acacia mearnsii, Eucalyptus spp. and Pinus taeda. The 40,183 analyses were separated by chemical element, component and species. The limits with base in the results of the tests of adherence to the normal distribution and in the classification criteria were established. The results of the obtained medium tenors are inside of the strip of values found in the literature for the studied forest species, components of the biomass and chemical elements. The levels of the chemical elements are different among the species for each type of analyzed component. Independent of the studied forest species, the leaves and needles presented larger values while the buds trunk smaller. The limits, proposed in the work, allow greater control in the classification of the results, increasing the reliability in the nutritional analyses.

Ion input via rainwater in the southwestern region of Rio Grande do Sul, Brazil.

Ion input via rainfall alone and after interception by the forest canopy, constitutes an important path of biochemical cycling, although few studies have provided information on the subject so far. The objective of this work is to quantify ion inputs, via rainfall, in the southwestern region of Rio Grande do Sul state, Brazil. Ten rain gauges were mounted in a field area. The quantification of stored water volume, along with sample collection for determination of nitrate, nitrite, ammonium, phosphorus, sulfur, chlorine, calcium, magnesium, potassium and sodium contents, was done fortnightly from September 2006 to August 2008. Local annual average precipitation in the relevant period was 1,588.3 mm. The concentration of chemical elements in rainwater was found to vary throughout, being inversely correlated with the increase in rainfall, while potassium, ammonium, phosphate, sulfate, chloride and sodium were found to have a significant mutual correlation (p <0.01). Based on the annual amount of nutrient input via rainwater, it can be inferred that rainfall is an important source of chemical element input into the forest system.

Estimativa de biomassa em povoamento de Platanus x acerifolia (Aiton) Willd. estabelecido no município de Dom Feliciano, RS.

This study aimed at estimating the biomass in a 5.5-year- Platanus x acerifolia stand, in Dom Feliciano county, Rio Grande do Sul. The inventory in the experimental area was done in five plots (20 m x 30 m each one). Trees were grouped in eight diameter classes, and 3 trees per class were cut. After cutting the trees, a cubing was done and the biomass of each component (leaf, fruit, branch, bark, wood and root) was determined and sampled. The biomasses estimative from each component were done through regression equations adjustment that correlated dendrometric characteristics with biomass volumes from the respective components of the trees. The total biomass was 45,28 Mg h -1 , distributed in: wood 21,07 Mg ha -1 ; branch 11,72 Mg ha -1 ; root 8,43 Mg ha -1 ; bark 2,01 Mg ha -1 ; leaf 1,89 Mg ha -1 and fruit 0,16 Mg ha -1 . The accumulated litter was 12,80 Mg ha -1 .

NUTRIENT ALLOCATION IN Eucalyptus saligna Sm. STANDS IN THE REGION OF GUAÍBA - RIO GRANDE DO SUL

Este trabalho, realizado em povoamentos de Eucalyptus salignaSm., entre 2 e 7 anos de idade, na regiao de Guaiba - RS, teve como objetivo: estimar o estoque de nutrientes na biomassa. Com base no inventario florestal, arvores de diâmetro medio foram coletadas e fracionadas em folha, galho, casca do tronco, madeira do tronco e raiz. A serapilheira acumulada foi avaliada com unidades amostrais de 1 m2. Amostras dos componentes arboreos e de serapilheira foram coletadas para estimativa da massa seca e da concentracao de nutrientes. O estoque de nutrientes foi obtido pelo produto entre a biomassa media de cada componente e a concentracao media de nutrientes. Para a media dos povoamentos, o estoque de nutrientes apresentou a seguinte ordem de acumulo, para os componentes da biomassa: madeira do tronco > raiz > folha > casca > galho; e para nutrientes: Ca > N > K > Mg> P.

Nutrientes na serapilheira acumulada em um povoamento de Eucalyptus saligna Smith em São Grabriel, RS

O objetivo deste trabalho foi, quantificar o estoque de nutrientes na serapilheira acumulada em um povoamento de Eucalyptus saligna Smith aos 4 e 5 anos de idade no municipio de Sao Gabriel – RS. Todo o material coletado, ao final de cada estacao do ano, foi levado para o Laboratorio para determinacao dos macronutrientes. O total de serapilheira acumulada sobre o solo para os anos de 2011 e 2012 foi de 12,76 e 12,00 Mg ha -1 , respectivamente. As quantidades de N, P, K, Ca, Mg e S estocadas na serapilheira foram de 94,4; 4,8; 21,8; 138,8; 25,6 e 8,8 kg ha -1 respectivamente. A serapilheira acumulada e uma excelente fonte de materia orgânica e reserva de nutrientes para as rotacoes futuras.

TEOR E ALOCAÇÃO DE NUTRIENTES EM PLANTIO DE Platanus x acerifolia (Aiton) Willd. EM DOM FELICIANO – RS

This study had as objective to evaluate nutrients content and allocation pattern in different biomass components of Platanus x acerifolia, in a 5.5 year stan...