Variabilidade espacial de clones de eucalipto em função do preparo de solo e adubações

Abstract

In order to estimate the productivity of forest stands,geostatistics can be used to describe the spatial variability pattern, which allows to observe and explain the sites of higher productivity. It is necessary to define the variability as it allows to apply specific managements for each area, due to the lack of information about the variability of the tillage of soil and fertilization in eucalyptus it is necessary studies of this nature. The objective of this study was to evaluate the spatial variability of eucalyptus clones as a function of soil preparation and fertilization. The variables were height, diameter and volume of wood from homogenous plantations at 36 and 48 months of age and were implanted in four types of soil preparation, two fertilizations and two genetic materials. For the analyzes of spatial distributions and semivariograms, GS+ software was used. The spatial dependence index was defined from the parameters based on the relative size of the nugget and threshold effect. Being; strong spatial dependence ≤ 25%; moderate spatial dependence between 26% and 74% and weak spatial dependence when ≥ 75%. The genetic material presented differences and the fertilizations did not differ. The spatial dependency index was moderate. Conventional tillage and subsoiling showed the best results for eucalyptus growth. For the diameter, no-tillage presented greater development at 36 months and conventional at 48 months. For spatial analysis, the exponential model presented the best geostatistical values,the range was higher than the smaller distance between the points, showing spatial.