The productivity of eucalyptus stands found in Belo Oriente, Nova Era and Guanhães areas in the Rio Doce Basin, Minas Gerais State were analyzed. The precipitation events occurred over the rainy seasons as well as the water balance components by Thornthwaite and Mather, in 1955, relative to the period from January 1985 to December 1998 were studied, in order to determine the influence of these components on the gain of the annual average volume of wood (m³ha-¹). To do so, the forest inventory data from the Empresa Florestal Celulose Nipo-Brasileira - CENIBRA, relative to the 3 - 7 year age range, were used. Wood productivity was affected by the total precipitation in the rainy season (PEC). The lowest values of the monthly periodic increment (IPM) were observed in those years preceded by dry (S) or very dry rainy season (MS), whereas the highest IPM values occurred in those years preceded by rainy season so-classified as rainy (C) or very rainy (MC). Taking into account that this fact was more pronounced in both Guanhães and Nova Era, the correlation between PEC finished at every year and IPM for either the increase (1986 to 1992) and decrease periods (1992 to 1995) in PEC were verified; these correlations reached a r²above 80%. For a 100 mm increase in PEC from a year to another, the increase in IPM averaged 0.445 m³ha-1mo-1, whereas for a reduction of 100 mm the decrease in IPM was 0.64 m³ha-1mo-1 for both regions. Guanhães showed the highest average site index as well as the highest average productivity, following the Nova Era and Belo Oriente regions.
Forest productivity; sequential hydric balance; climate influence
