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Purpose: The role of soil biotic and abiotic factors in crucial ecosystem services such as primary production, organic matter dynamics, nutrient cycling, and soil biota community structure in the Araucaria ecosystem remains poorly quantified. We aimed to understand how the site quality affects the development of organic horizons, root growth, soil chemical properties, and the entire soil biota community in even aged and monospecific Araucaria angustifolia plantations. Methods: We collected soil monoliths to describe layers of organic matter and the complex soil food web into these layers. We determined soil pH, soil moisture, total nitrogen, available P, and total organic carbon into each layer (litter, F-layer, H-layer, and A horizon), the biomass of fine roots, the community structure of soil biota, arbuscular mycorrhizal fungi, and nematodes, as well as the microbial biomass carbon. Results: In the high-quality site, there was significantly higher organic matter formation, nutrient cycling (N and P), root growth, soil moisture, soil biota diversity, arbuscular mycorrhizal fungi, nematodes, and microbial activity evaluated by the microbial biomass carbon compared to the low-quality site. Conclusions: High-quality sites promote the development of organic horizons, root growth on superficial layers that provide plant nutrient release, the A horizon nutrient contents, and the entire soil biota community in monospecific Araucaria angustifolia plantations located on humid subtropical Cambisols. This creates a positive plant-soil feedback that maintains soil quality and increases primary production, nutrient cycling, and habitat and food for the soil food web.

Although A. angustifolia is currently economically unimportant, the worldwide trend of conservation through the sustainable use of natural resources together with an intense discussion of governmental regulations and the recent results of genetic breeding started in the 1970s are delivering promising perspectives for a new wave of plantations. This study aimed to determine optimal pruning strategies by evaluating the diameter and height growth of young A. angustifolia trees as affected by different pruning intensities. Pruning quality in terms of occlusion and defect-core size were also investigated. At the age of 6 years, the pruning experiment was started by conducting six different pruning intensities, named after the number of whorls left after pruning (0, 2, 4, 6, and 8), as well as unpruned (U) trees as a control. From the results obtained in the present study, it was concluded that pruning intensity had a significant negative effect on the growth of young A. angustifolia trees. Diameter was more affected than height growth. Pruning young A. angustifolia trees for knotty-free timber production must be conducted keeping 8 whorls after the intervention if no negative effect in current annual increment in diameter is to be observed when compared to unpruned trees. A defect core of 15 cm seems to be a feasible target for the species regarding optimal pruning intensity to avoid losses in diameter growth. This is strongly dependent on a fast occlusion process, which, in turn, is a result of a careful pruning technique.

Plantation forestry in southern Brazil demands additional timber species to a higher market differentiation by providing high quality timber and exploitation of market niches. Cupressus lusitanica has long been recognized for this purpose but, until now, it was not properly region-wide quantified in terms of growth and yield. The present study delivers the lacking quantitative approach, which may encourage the commercial use of the species. With this study it was aimed at collecting and processing quantitative data from all known C. lusitanica stands in southern Brazil. Inventories were carried out (60 ha, 6-39 years of age) in order to model the development of dominant height (h100), basal area, volume and dominant diameter (d100). Dominant height was the basis for site quality evaluation, delivering site index curves, which, together with the commercial volume of the stands, allowed yield modelling. A wide amplitude of dominant height growth was detected (10-30 m at 20 years), indicating a great site quality variation. At age of 20 years, commercial volumes of 110 and 620 m³ ha-1 were observed for site indexes of 14 and 26, respectively, equivalent to a maximum of 6-31 m³ ha-1 year-1 at ages between 16-18 years. Results demonstrated in a robust manner that C. lusitanica has a high potential for cultivation in southern Brazil. Thus, offering the opportunity of market differentiation by promoting market niches whose demands timber for special solid end-uses.

The purpose of this study was to evaluate the natural durability of Cupressus lusitanica , Cryptomeria japonica and Pinus taeda woods subjected to a rotting field trial, through mass loss and deterioration index. The trial was conducted in an open field in the city of Curitibanos, State of Santa Catarina, Brazil, for a 24-month period, with evaluations carried out every 6 months. For developing the study, we used the woods of Cupressus lusitanica (16 years) , Cryptomeria japonica (16 years) and Pinus taeda (juvenile=15 years and mature wood>30 years) species, from which test specimens were made with the dimensions of 2.5 x 5.0 x 50.0 cm in thickness, width and length, respectively, following the standards suggested by IUFRO. After 24 months of exposure to the rotting field the woods of C. japonica and C. lusitanica species showed a deterioration index that reflected an evident but moderate attack of fungi and termites, while the woods of P. taeda (juvenile) and P. taeda (mature) showed deterioration index that reflected an intense rotting and intense attack of termites. Regarding the mass loss the woods of C. japonica and C. lusitanica were classified as highly resistant, while P. taeda (juvenile) was considered resistant and P. taeda (mature) was considered moderately resistant. In general, the woods of C. lusitanica and C. japonica showed greater natural durability when used in contact with the soil.

Although the historical interest in using the wood of Araucaria angustifolia , it is still little known concerning the factors that affect the growth. A broader understanding in this context might contribute to the development of appropriate management systems, thus increasing the productivity of plantations and, consequently, the interest in commercially using this species. The present study was based on monospecific populations established in different site conditions (Site Indices between 18-24) where individuals (n=654) were submitted to different competition levels. With the aid of multiple regression techniques, the factors that significantly affected the accumulated growth in diameter of the trees after 20 years of intervention were determined. For the set formed by all trees, 77% of the growth variation can be explained by three factors: site, the proportion of tree diameter at breast height ( dbh ) of the object tree for analysis in relation to the average dbh of the population before performing the clearings (C dbh _before ) and dominance status in relation to the neighboring trees (C all ). The significance of the competition level before the clearing shows that late clearings have limited effects on tree growth. It is concluded that individuals are benefited for having a dominant position in relation to the neighboring trees, reaching diameters 50% larger at the end of the production cycle. Clearings that favour selected trees by removing direct competitors seem to be an interesting management strategy for the species. Keywords: Parana-pine; Forest Management; Silviculture; Timber Production.

A busca por maior produtividade, menores ciclos de producao e, consequentemente, maior desempenho economico tem levado empresas e proprietarios rurais do Planalto Sul do Brasil a investir em plantacoes de Eucalyptus em detrimento de Pinus . A determinacao da produtividade e do desempenho economico de povoamentos florestais e fator basico para o planejamento e otimizacao do manejo destes. Nesse contexto, o presente estudo foi realizado com o intuito de avaliar o crescimento e o desempenho economico de plantios de Eucalyptus dunnii em diferentes sitios no Planalto Sul do Brasil. Foram utilizados dados de inventario florestal continuo, totalizando 128 unidades amostrais e 10.903 pares de dados dap x h dom . Foram obtidas tres classes de sitio com alturas dominantes assim distribuidas na idade indice de 10 anos: Classe I: 34 a 39 m; Classe II: 29 a 33,9 m; Classe III: 24 a 28,9 m. Povoamentos com d 200 de 30 cm podem ser obtidos ja aos 9 anos de idade em sitios altamente produtivos. Entretanto, demoram de 3 a 5 anos a mais para serem obtidos em sitios menos produtivos. A taxa interna de retorno (TIR) de sitios altamente produtivos e duas vezes maior que em sitios de menor produtividade. Valor presente liquido (VPL) e valor esperado da terra (VET), no sitio de alta produtividade, sao 14 vezes superiores aos observados nos piores sitios. Conclui-se nao so quee mais rentavel produzir E. dunnii em sitios mais produtivos, mas tambem que o cultivo de E. dunnii pode nao ser viavel em sitios pouco produtivos. Palavras-chave: Manejo Florestal; Eucalipto; Manejo para Multiprodutos. Abstract Growth and economic performance of Eucalyptus dunnii at different sites on the Highlands of Southern Brazil. The search for greater productivities, shorter production cycles and thus higher economic performances have led companies and landowners on the Highlands of Southern Brazil to invest in Eucalyptus plantations rather than Pinus . Determining the productivity and economic performance of forest stands is a key factor for their planning and management. In this context, the present study was carried out aiming to evaluate de growth and economic performance of Eucalyptus dunnii in different sites on the Highlands of Southern Brazil. Data from continuous forest inventory were regarded with a total of128 sample plots and 10.903 dbh x h dom paired values. Three site classes were obtained with dominant heights at index age of 10 years as the following: Class I: 34 to 39 m; Class II: 29 to 33,9 m; Class III: 24 to 28,9 m. Stands of d 200 of 30 cm can be obtained since the age of 9 years-old on sites of high productivity, while it takes from 3 to 5 years on sites of lower productivity. The internal rate of return (IRR) on sites of high productivity is twice as high as the ones verified on sites with lower productivity. Net present values (NPV) and land expectation values (LEV) on sites of high productivity are 14 times higher than the ones observed on the worst sites. It was concluded that it is not only more profitable to grow E. dunnii on sites of high productivity, but also that there might be no viability at all of its cultivation on low productivity sites. Keywords: Forest Management; Eucalypt; Multiproducts Management.

A silvicultura de Cunninghamia lanceolata em sua região de origem é amplamente difundida, em função do bom desenvolvimento e da qualidade da madeira para usos industriais diversificados. No Brasil, a espécie é considerada de grande potencial. O presente estudo teve como objetivo levantar aspectos dendrométricos e silviculturais de um povoamento puro de C. lanceolata, com 21 anos de idade e o ajuste de modelos hipsométricos, de volume individual e de afilamento. Confirmou-se o potencial silvicultural de C. lanceolata para a região de planalto do Sul do Brasil. A espécie apresenta crescimento inicial lento, demorando cerca de quatro anos para o seu pleno estabelecimento. Entretanto, o incremento médio anual em volume é satisfatório (28,1 m³ ha-1 ano-1), mesmo em condições de elevada competição (65,3 m² ha-1). Mediante os testes realizados, os melhores ajustes foram obtidos para as equações de Trorey, Schumacher-Hall e Hradetzky, para estimar a altura total, volume individual e afilamento, respectivamente.

In the construction sector, wood is facing competition with other materials such as concrete, steel or plastics. Therefore, there is a need for more efficiency in the forest–wood chain by improving silvicutural management and wood processing technologies. The objective of the study is to analyse the influence of log diameter and quality to recovery rate, veneer quality and economic benefit. The trees used in the study came from a 30-year-old Pinus taeda L. thinning trial in Southern Brazil. In total, 57 logs (20.7 to 67.0 cm) were peeled following the standard industrial processing methods of the plywood mill. Average recovery rate was 54 % ranging from 35 to 72.6 %, with a linear trend (R 2 = 0.48) of increasing recovery with an increment on the log small-end diameter. Results show that the gap between theoretically possible and real recovery was lower in the logs with bigger diameters, indicating their higher efficiency in industrial processing. Moreover, the economic analysis detected that the current prices for log assortments reflect only the industrial potential of low-quality pruned logs. An optimised pruning strategy would result in higher industrial efficiency, which would allow higher log prices. The results indicate that the recovery rate of bigger logs is higher in terms of volume of peeled veneer. The quality and therefore the value obtained from each log were negatively influenced by inadequate pruning strategies. Management of pines for higher value utilisation requires optimized thinning and pruning strategies in order to meet high growth rates and proportionally bigger dimensions of clear wood.

Eucalytpus dunnii é uma espécie subtropical e tem seu cultivo indicado para regiões onde há ocorrência de geadas. Apesar de ser atualmente utilizada para a produção de papel, carvão e chapas, o uso sólido da madeira para fins mais nobres é conhecido, desde que práticas silviculturais como podas e desbastes sejam consideradas. O presente estudo teve como objetivo analisar o crescimento de indivíduos dominantes de E. dunnii submetidos a diferentes intensidades de poda. Foram testadas quatro diferentes intensidades de poda, mantendo uma copa remanescente de 100, 80, 50 e 20% da altura total de árvores dominantes. Foi utilizado um delineamento inteiramente casualizado com 10 indivíduos por tratamento. Passados 20 meses da realização da poda, a manutenção de até 50% da copa foi suficiente para manter um crescimento em diâmetro considerado normal. Mais importante que a proporção de copa remanescente, é o comprimento absoluto das mesmas. Conclui-se que são necessários, no mínimo, 4 m de copa remanescente para que as árvores mantenham um incremento periódico anual acima de 4 cm (média anual durante o período de 17 a 37 meses). Ao ultrapassar este limite, perdas na ordem de 50% do incremento em diâmetro são esperadas.AbstractOptimum pruning intensity in Eucalytpus dunnii for clear wood producing. Eucalyptus dunnii is a subtropical species, indicated for areas where frosts occur. Besides its current utilization for paper, coal and boards production, the potential for nobler solid-uses are recognized, provided that silvicultural practices such as pruning and thinning are regarded. The objective of this study was to analyze the growth of dominant E. dunnii trees subjected to four different pruning intensities: 100, 80, 50 and 20% of the total tree height of remained canopy. Experimental design was fully randomized, with 10 replications per treatment. After 20 months of pruning, maintaining 50% of canopy was sufficient to allow a normal diameter growth. More important than the proportion, was the absolute length of remained canopy. It was concluded that it is necessary to keep, at least, 4 m of remained canopy in order to maintain a periodic annual increment over 4 cm (average during the 17-37 months period). When this threshold is exceeded, lost in the order of 50% in diameter increment are expected.Keywords: Forest Management; Multiple-uses.

Cryptomeria japonica e originaria da regiao temperada do Japao, onde e amplamente plantada em funcao da alta durabilidade e trabalhabilidade da madeira. O objetivo do presente trabalho foi avaliar o desempenho de procedencias japonesas de C. japonica , implantadas em 1980 na Estacao Experimental da Universidade Federal do Parana, municipio de Rio Negro, Parana. Realizou-se levantamento dendrometrico em setembro de 2011, o qual serviu de base para as analises estatisticas e geneticas. A produtividade observada aos 31 anos variou de 9,3 m³.ha -1 .ano -1 na testemunha (Camanducaia), ate 22,2 m³.ha -1 .ano -1 na procedencia Miyagi. A partir dos resultados, foram propostas estrategias de melhoramento genetico para a criacao de uma Area de Producao de Sementes (APS) e um Pomar Clonal de Sementes (PCS), bem como a selecao de individuos superiores para reproducao assexuada. Para tal, considerou-se uma intensidade de selecao que mantivesse ao maximo a variabilidade genetica entre procedencias, mas explorasse a variacao dentro de cada procedencia. As sementes produzidas terao um ganho no crescimento diametrico estimado em 9,2% para a APS (curto prazo) e de 14% para o PCS (medio prazo). Abstract A proposal for the existing germplasm of Cryptomeria japonica (L.F.) Don. at the Experimental Station of Rio Negro, PR, aiming at the production of genetic improved seeds. Cryptomeria japonica is indigenous to the temperate region of Japan where it is widely planted, due to its wood quality, high durability and workability. The aim of this study was to evaluate the performance of Japanese provenances of C. japonica , established in 1980 at Experimental Station of Parana Federal University, municipality of Rio Negro, Parana State. Dendrometric measurements were carried out in September 2011, which was the basis for statistical and genetic analysis. The productivity at age 31 years ranged from 9.3 m³.ha -1 .year -1 (control), up to 22.2 m³.ha -1 .year -1 (Miyagi). A breeding strategy was proposed based on a seed production area (SPA) and on a clonal seed orchard (CSO). Moreover superior individuals for vegetative reproduction were also selected. The selection intensity was suggested considering the maintenance of expressive genetic variability among provenances, but exploring the variation within each provenance. The estimated genetic gain for diameter growth was 9.2% for the SPA (short term) and 14% for the CSO (medium term). Keywords : Forest breeding; seed production area; clonal seed orchard.

Embora o uso tradicional para a madeira do gênero Eucalyptus no Brasil seja a obtenção de papel e energia, diversas espécies desse gênero são consideradas de grande potencial para a produção de painéis, compensados, lâminas e móveis. Para permitir um uso mais nobre da madeira desse gênero, o manejo tradicional precisa ser substituído por rotações maiores, com aplicação de desbastes e podas. O presente estudo teve como objetivo avaliar os efeitos de três diferentes intensidades de desbaste no crescimento em diâmetro, área basal e volume em um povoamento de Eucalyptus dunnii. Os tratamentos foram aplicados mantendo 16, 14 e 12 m² remanescentes por hectare, além da testemunha, realizados em dois diferentes momentos, 3° e 4° ano. A análise do povoamento ocorreu quando ele estava com sete anos de idade, decorridos quatro e três anos da realização do primeiro desbaste. Concluiu-se que o diâmetro médio é maior, quanto menor a área basal remanescente após o desbaste, e que a diferença entre os tratamentos tende a aumentar com o tempo. A redução da área basal para, pelo menos, 14 m²/ha, quando o povoamento possuir 20 m²/ha, é recuperada em termos de estoque volumétrico passados três anos da realização do desbaste.