Growth of eucalyptus seedlings subjected to the application of biosolids

Abstract

Before the recommendation of use of biosolids in large scale in forest plantations, we must understand their effects in soil and plant. Thus, the growth of eucalyptus seedlings fertilized with different doses of sewage sludge from home was assessed in an experiment from July to October of 2007 in the Studies and Dissemination of Technology in Forest, Water Resources and Sustainable Agriculture Nucleus, in containers of 50 L filled with latossol. The experiment was mounted in a randomized design in a factorial 5 × 5 (five treatments and five incubation periods) with four replications. The treatments consisted on application of doses of sewage sludge (0; 25; 50; 75 and 100 ton ha^-1) and incubation periods were 0; 20; 40; 60 and 80 days. In each period of incubation was performed an analysis of growth where a plant was removed from each experimental unit for determination of leaf area, total dry weight, ratio of leaf area and growth rates. Considering the specific case of sewage sludge characterized in this work, its application in the quantities used, increased the values of leaf area, total dry matter, leaf area ratio and rates of absolute and relative growth of the plants of eucalyptus. Moreover, the incubation periods set provided no changes in the characteristics evaluated, except for leaf area that increased with the increase of days.