Definition of environmental sites in Espirito Santo state based on relief, soil and climate/ Delimitacao de sitios ambientais homogeneos no Estado do Espirito Santo, com base no relevo, solo e clima

The objective of this study was to define homogeneous environmental sites in the state of Espirito Santo, Brazil which may possibly be used to indicate potential soil use for the entire state. Multivariate statistics techniques were employed using information of the relief and geographical coordinates, as well as soil and climatic data. Water availability and real and potential evapotranspiration were determined from the results of the climatological water balance. Initially a principal component analysis (PCA) for the climatological data was performed. Subsequently, a grouping analysis was executed on the relief, soil and climatic data provided by the PCA and geographical coordinates. The first two axes of the PCA define roughly 85.3% of the total accumulated variance. After rotation of the principal components, the variables that best correlated to the first axis were the thermal amplitude, average annual temperature, followed by real evapotranspiration. Six environmental sites were defined for the state of Espirito Santo, some presenting climatic similarities. The topographic variables were the factors of greatest influence on the sites differentiation. The methodology was appropriate in defining the sites. Key words: climate zoning, multivariate statistics, water balance. Este trabalho teve como objetivo definir sitios ambientais homogeneos no Estado do Espirito Santo, a fim de indicar o uso potencial do solo de todo o seu territorio. Tecnicas estatisticas multivariadas foram empregadas sobre informacoes do relevo, coordenadas geograficas, dados do solo e clima. A disponibilidade hidrica e a evapotranspiracao real e potencial foram determinadas a partir do resultado do balanco hidrico climatologico. Inicialmente, foi executada a analise de componentes principais (ACP) sobre os dados climaticos e, em seguida, a de agrupamento nas informacoes do relevo, solo, nos escores climaticos provenientes da ACP e nas coordenadas geograficas. Os dois primeiros eixos da ACP explicam cerca de 85,3% da variancia total acumulada. Apos a rotacao dos componentes principais, as melhores variaveis correlacionadas ao primeiro eixo foram a amplitude termica, a temperatura media anual, seguida da evapotranspiracao real. Foram definidos seis sitios ambientais para o Estado do Espirito Santo e alguns apresentaram similaridades ao clima. As variaveis topograficas foram os fatores de maior influencia na diferenciacao dos sitios. A metodologia se mostrou adequada na definicao dos