Sewage sludge compost for initial cultivation of eucalyptus

Abstract This study evaluated the feasibility of sewage sludge compost obtained from a sewage treatment plant as an alternative “Class D” organic fertilizer for the initial cultivation eucalyptus. The experiment was conducted in a greenhouse at CCA - UFSCar, Araras, SP. Cultivation occurred in 11 L pots for 75 days. We adopted a completely randomized design, with five treatments and seven repetitions. The tests considered a control treatment with no fertilization, three treatments with sewage sludge compost addition (25%, 50%, and 75% of the pot volume) and a treatment with conventional mineral fertilizers, all in sandy soil. At the end of the experiment, plant relative growth rate and dry mass were evaluated and submitted to analysis of variance, followed by a Tukey test at 5% probability. Treatments with fertilization had a greater relative growth rate than the control; however, we found no difference between mineral and organic fertilization. Plant dry mass was higher in the treatment with 50% of the pot filled with organic fertilizer. Thus, we conclude that the tested sewage sludge compost is a potential substitute for conventional mineral fertilization for the initial cultivation of eucalyptus.

摘要 本研究评估了某污水处理厂产出的污泥堆肥作为桉树初始种植用替代“D级”有机肥的可行性。试验在位于圣保罗州阿拉拉斯市的CCA - UFSCar温室中开展。试验采用11升容积的盆栽容器，种植周期为75天。本试验采用完全随机设计，设置5个处理组与7个重复单元。试验包含不施肥的空白对照组、3个添加不同比例污泥堆肥的处理组（堆肥占盆体容积的25%、50%与75%），以及1个常规矿物肥料处理组，所有处理均以沙土作为栽培基质。试验结束后，测定植株相对生长速率与干物质质量，先进行方差分析，随后在5%显著性水平下开展Tukey检验。各施肥处理组的植株相对生长速率均显著高于空白对照组，但常规矿物肥料处理与有机肥处理之间未出现显著差异。当有机肥占盆体容积50%时，植株干物质质量达到最高。综上，本试验所用的污泥堆肥可作为桉树初始种植阶段常规矿物肥料的潜在替代方案。