Stanley Schettino

Dinâmica da regeneração natural em uma floresta ombrófila densa secundária, após corte de cipós, Reserva Natural da Companhia Vale do Rio Doce S.A., estado do Espírito Santo, Brasil

The objective of this work was to evaluate the succession dynamics, growth and production of a secondary dense ombrophylous forest, after vine cutting. The silvicultural treatment was performed to promote a rapid return of the forest to its primary conditions, or, at least, to shorten the time interval between two successive cutting cycles. Data were collected on an experiment established in 1989 measured every two years at the Vale do Rio Doce Natural Reserve, which is located between the municipalities of Linhares and Jaguare, Espirito Santo, Brazil. Sampling was systematic, and all the individual trees with dbh < 5.0 cm were considered as pertaining to natural regeneration. The effects of the treatment upon floristic composition, species diversity, and natural regeneration structure were evaluated in each monitoring period. It was concluded that, for all the categories analysed, great positive variations occurred in the natural regeneration rates and in the increase of the basal area of these individuals during monitoring. This indicates that this forest compartment was most benefitted from the treatment, as well as, indirectly, the arboreal stratum, with the ingrowth of these individuals. Thus, vine cutting favoured the secondary succession dynamics, decreasing the competition for space, nutrients and light, allowing natural regeneration development and a great increase of the ingrowth rate of new individuals in the arboreal stratum.

Dinâmica da composição florística de uma floresta ombrófila densa secundária, após corte de cipós, Reserva Natural da Companhia Vale do Rio Doce S.A., estado do Espírito Santo, Brasil

RESUMO - O objetivo deste trabalho foi analisar a dinâmica da composicao floristica de uma Floresta Ombrofila Densa secundaria, apos o corte de cipos. O tratamento silvicultural foi executado com o objetivo de promover o rapido retorno da floresta as suas condicoes primarias ou, no minimo, diminuir o intervalo de tempo entre dois ciclos de corte sucessivos. Os dados foram provenientes de um experimento implantado em 1989 e medido bienalmente na Reserva Natural da Companhia Vale do Rio Doce S.A., municipios de Linhares e Jaguare-ES, Brasil. A amostragem foi sistematica (35 parcelas permanentes retangulares), tendo sido considerados como individuos adultos as arvores com dap ≥ 5,0 cm. Foram avaliados os efeitos da aplicacao do tratamento sobre a composicao floristica e a diversidade de especies, em cada ocasiao de monitoramento. No tocante as especies arboreas, o tratamento pouco influenciou a dinâmica da composicao floristica. Embora a diversidade tenha aumentado (0,55% pelo indice de Shannon-Weaver), os demais indices apresentaram decrescimo, o que indica que houve elevada taxa de ingresso das especies preexistentes na area, ou seja, o aumento do numero de individuos na populacao esta ocorrendo em taxas maiores do que o incremento no numero de especies. Ja a estrutura da floresta (estrato arboreo) foi bastante influenciada, pois os substanciais aumentos em numero de arvores e area basal indicam que as taxas de recrutamento e crescimento estao superando as de mortalidade. Da mesma forma, os grupos ecofisiologicos das secundarias tardias e climaxicas foram os mais beneficiados, sendo mais um indicativo de que o tratamento esta favorecendo a dinâmica de sucessao secundaria.

Avaliação ergonômica da colheita florestal em área com madeira danificada pelo vento

Este estudo teve por objetivo realizar a analise ergonomica do trabalho de seis atividades de colheita florestal em area danificada pelo vento. Para cada uma das atividades, foi realizada a avaliacao biomecânica, atraves da aplicacao do Modelo Biomecânico Tridimensional de Predicao de Posturas e Forcas Estaticas (3DSSPP TM ), desenvolvido pela Universidade de Michigan, alem dos fatores ambientais calor, vibracao e ruido, de forma a determinar os riscos ergonomicos a que os trabalhadores estavam expostos durante o desenvolvimento da colheita florestal. A avaliacao biomecânica indicou que para as atividades de extracao e carregamento manual os valores de carga estavam acima do limite recomendado, com elevado risco de desenvolvimento de lesoes na coluna vertebral e nas articulacoes avaliadas. As condicoes termicas do ambiente de trabalho, apresentaram risco aos trabalhadores, principalmente no periodo da tarde e em todas as atividades. O ruido foi o fator ambiental que apresentou maior risco ergonomico aos trabalhadores das atividades de derrubada e tracamento, seguido da vibracao. Conclui-se que a colheita de madeira em area danificada pelo vento possui elevado risco ergonomico para os trabalhadores durante a execucao de suas atividades, o que, aliado as condicoes ambientais adversas, proporciona elevados e iminentes riscos de desenvolvimento de lesoes e doencas osteomusculares relacionadas ao trabalho.

CLASSIFICATION OF FOREST ROADS AND DETERMINATION OF ROUTE USING GEOGRAPHIC INFORMATION SYSTEM

Geographic Information System (GIS) is an indispensable software tool in forest planning. In forestry transportation, GIS can manage the data on the road network and solve some problems in transportation, such as route planning. Therefore, the aim of this study was to determine the pattern of the road network and define transport routes using GIS technology. The present research was conducted in a forestry company in the state of Minas Gerais, Brazil. The criteria used to classify the pattern of forest roads were horizontal and vertical geometry, and pavement type. In order to determine transport routes, a data Analysis Model Network was created in ArcGIS using an Extension Network Analyst, allowing finding a route shorter in distance and faster. The results showed a predominance of horizontal geometry classes average (3) and bad (4), indicating presence of winding roads. In the case of vertical geometry criterion, the class of highly mountainous relief (4) possessed the greatest extent of roads. Regarding the type of pavement, the occurrence of secondary coating was higher (75%), followed by primary coating (20%) and asphalt pavement (5%). The best route was the one that allowed the transport vehicle travel in a higher specific speed as a function of road pattern found in the study.

CORRELAÇÃO ENTRE VOLUMETRIA DE FLORESTAS DE EUCALIPTO E PRODUTIVIDADE E CUSTOS DE MÁQUINAS DE COLHEITA DE MADEIRA

The mechanization of forest harvesting activities has become imperative to their sustainability, seeking productivity gains and operating costs reduction. As the operating costs and the productivity of forest machines can be influenced by the volumetry of forests (m3/ha), knowledge of this correlation can be an important tool in the harvest planning. This study was conducted in eucalyptus harvest areas in the state of Minas Gerais. The main objective was to technically and economically evaluate the mechanized harvesting activities as well their correlation with volumetry of forests. For this, were applied linear regression statistics techniques and correlation analysis between the volumetry of forests and the productivity and operating costs of harvesting machines. The results showed a strong correlation between the volumetry of forests andproductivity of machines as well as operating costs, demonstrating increase of productivity of the machines and reduction of harvesting costs with increasing volumetry of forests. The feller buncher presents higher correlation, followed by the extraction machineries (skidder and clambunck skidder) and grapple saw, this one probably more susceptible to other operationalfactors. The volumetry of forests should be considered when indicating and sizing of the machines for harvest, as well as in planning activities in order to increase the productivity of activities and contribute to reduction of operating costs.