Condutividade elétrica aparente do solo como ferramenta à silvicultura de precisão

• Ano de defesa: 2014
• Autor(a) principal: Brito, Matheus Duarte de
• Orientador(a): Queiroz, Daniel Marçal de
• Banca de defesa: Leite, Fernando Palha , Soares, Vicente Paulo
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Engenharia Agrícola
• Departamento: Construções rurais e ambiência; Energia na agricultura; Mecanização agrícola; Processamento de produ
• País: BR
• Palavras-chave em Português: Agricultura de precisão; Solos florestais; Eucalipto; Florestas - Administração
• Palavras-chave em Inglês: Precision Agriculture; Forest soils; eucalyptus; Forests - Administration
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::ENGENHARIA AGRICOLA
• Link de acesso: http://locus.ufv.br/handle/123456789/3684

This concept of precision forestry, which is based on operational efficiency, is applicable in all steps of the forest production cycle, from soil preparation to harvesting. Understanding the spatial variability of production ́s characteristics summarizes the ideology proposed by this model. The soil variability across a field has received special attention from farmers and researches due its direct effects on productivity and wood quality. However, determining subfield areas based on nutrients concentration and other soil properties is difficult and laborious, because a high sampling density would be required in order to achieve a good field variability representation. Geophysical methods have been used in agriculture to this goal, for instance, the geospatial measurements of apparent electrical conductivity (EC a). This soil characteristic is correlated with others soil attributes, what justify its using in soil quality evaluating. The objective of this study was apply the use of ECa in forestry plantations, and contribute to its diffuse as a precision forestry tool. Thereby, was evaluated, a priori, the correlation between EC a and soil properties in a forestry soil, besides topographic attributes. ECa was not well correlated with topographic characteristics, but the correlation was high with the most soil properties considered. Thus, the ECa might be used as an instrument to evaluate site quality as well as to improve the traditional soil sampling method. To elucidate ECa use it was also discussed the appropriate time to collect field data as well as possible harvesting effect over its spatial pattern. Although it was found higher ECa values after- harvesting, the correlation coefficient between the two krigged maps (before and after-harvesting) indicated that the spatial patterns remains close. Finally, it was proposed and evaluated the combined use of EC a, soil wetness and clay content to delineate homogenous management zones, through fuzzy-k-means algorithm. An analysis of fuzzy performance index and modified partition entropy indicated two as the ideal number of management class. The validation process indicated that management zones delineated a good variability representation of soil properties and reinforced the potential ECa use as tool to precision forestry.