Papers by João Flávio da Silva
Ciência Florestal
The genetic gains from eucalyptus breeding programs have decreased, compared to the previous deca... more The genetic gains from eucalyptus breeding programs have decreased, compared to the previous decades, while the productivity has declined in recent years. This drop is mainly attributed to climate change, which, according to studies, has limited the productivity and altered the adaptation of forest species. In addition to this, it is considered that the soil is one of the components of the forest production that acts directly on the dynamics of water and nutrients for trees, and it is intended to evaluate the attributes of soils that maximize the productivity of wood to assist forestry companies in the indication of soils with better productive capacity to produce wood. Thus, the aim of the present study was to evaluate the influence of climate and soil attributes on the productivity of the eucalyptus forest and on the response to drought in Brazil (tropical and subtropical) in places with three types of climate: sub-humid, humid and super-humid. In addition, we sought to calculate...
Ciência Florestal, 2020
O objetivo do presente trabalho foi avaliar as correlações entre produtividade e resposta à seca ... more O objetivo do presente trabalho foi avaliar as correlações entre produtividade e resposta à seca (RS) do eucalipto entre os atributos do solo em dois tipos climáticos distintos no Brasil. Para isto, foram instalados 24 experimentos no Brasil com 4 clones comuns em todos os experimentos para obter fortes contrastes edafoclimáticos, e, desse modo, mensurar a produtividade e a reposta à seca e descrever as suas relações com os atributos de solos. Foram avaliados dois grupos climáticos: Úmido (relação precipitação: evapotranspiração entre 1,0 a 2,5) e Subúmido (relação precipitação: evapotranspiração entre 0,5 a 1,0). Os atributos dos solos avaliados foram: Areia, Silte, Argila, matéria orgânica (M.O.), capacidade de troca catiônica (CTC). Para os sítios localizados na classe climática Úmida, o VCCC correlacionouse negativamente com a M.O. e argila, e positivamente com a Areia. Para a RS, as correlações foram observadas para clima Subúmido para as variáveis CTC e Areia, e para o clima Ú...
Eucalyptus plantations cover about 1.5 percent of the agricultural area in Brazil, and contribute... more Eucalyptus plantations cover about 1.5 percent of the agricultural area in Brazil, and contribute to 4 percent of GDP and 3 percent in exports of forest products. Technological and research advances in silviculture and genetic improvement have increased productivity up to 80 m³ of wood/ha/year, with an average of 35 to 45 m³/ha/year. The greatest challenge to the introduction and commercial use of exotic species is the adaptation of species to climatic conditions. Even when maladapted species are able to survive, they are subjected to continuous stress that limits the expression of their maximum genetic potential. The incidence of insects and diseases frequently represent another limiting factor, because the exotic tree species have not co-evolved with most of the local insect and pathogen pests. In recent decades, the expansion of Eucalyptus plantations in Brazil has been frequently associated with frequent disease outbreaks. Prominent diseases, such as Ceratocystis wilt, Ralstonia...
Uploads
Papers by João Flávio da Silva