The effects of contrasting environments on the basic density and mean annual increment of wood from eucalyptus clones

Abstract

Eucalyptus plantations are some of the most productive, and adaptable to different environmental conditions. However, harsh environmental conditions can limit the quality of the wood, and its potential use. The TECHS project investigates the sensitivity of 18 eucalyptus clones to environmental stresses, and their productivity responses in different edaphoclimatic scenarios. The aim of this paper is to evaluate the influence of edaphoclimatic variables on the basic density (BD), and mean annual increment (MAI) of eucalyptus wood. Three different clones, planted at 10 growth sites in Brazil, 4 years of age, were analyzed. During the years 2012 to 2015. Variables such as precipitation, temperature, vapor pressure deficit, and the water storage capacity of the soil were considered. Canonical correlation techniques, principal components, and cluster analyses were performed in order to verify if there were influences of any of the edaphoclimatic variables on the set of production variables (BD and MAI). The variables were also used to organize the sites into groups based on their similarities. There was a significant influence of the edaphoclimatic variables at the different sites regarding the BD and MAI variables (rU1V1 = 0.77). Precipitation was positively correlated with the production variable (0.64), while the temperature (−0.59) and the vapor pressure deficit (−0.52) correlated negatively. The water storage capacity of the soil did not contribute to the set of edaphoclimatic variables that affected the production variable (0.16). Among the clones studied, E5 and G7 were more sensitive to climatic variations in different sites than the clone P7. The responses of the wood to the BD and MAI are clone-specific, and the mean annual increment of the wood changes in a greater proportion than the basic density faced with environmental variations. Understanding the responses of eucalyptus clones to environmental variations, mainly temperature and precipitation, facilitates forest planning, regarding the supply, and the quality of the wood.