Utilização do lodo de esgoto na vermicompostagem e como substrato para a produção de mudas de Pinus elliottii Engelm

Abstract

The urban population growth causes an increase in solid and liquid waste quantity produced by man. A viable alternative to use of these wastes would be its application in agricultural sector. The sewage sludge can fall as one of these residues. In Santa Maria/RS, a wastewater treatment plants collection a predominantly domestic sewage. Although this residue can be used in agriculture, may contain pathogens such as coliforms and helminth, attract vectors and have an unpleasant odor. In the present work had as objectives: 1) study the feasibility of using the vermicomposting process as treatment of sewage sludge, 2)evaluate the use of sewage sludge, pure or in mixtures, as a substrate to Pinus elliottii mycorrhizal seedling production. In first study examined the effect of sewage sludge in reproduction of earthworms Eisenia andrei, and evaluate the effect of earthworms on population of nematodes and faecal coliforms present in residue, over a period of 21 weeks. The second study was tested in greenhouse, the use of sewage sludge as substrate for growing pine seedlings inoculated with isolate UFSC ectomycorrhizal Sc 124, where the end of 80 days evaluated the dry matter of shoot and root, height, collar diameter, Dickson index quality and percentage colonization. The use of sewage sludge was acceptable as a substrate for multiplication of earthworms Eisenia andrei. The presence of earthworms in sewage sludge reduced the population of free-living nematodes present in residue. The amount of fecal coliform in sewage sludge reduced, remaining within the parameters established by law, however there was no effect of earthworms in the process. The use of sewage sludge mixed with peat fertile satisfactory growth of P. elliotii seedlings, inoculated with the ectomycorrhizal fungus UFSC Sc 124, the conditions under which experiment was conducted. Sewage sludge improved the physical conditions of the substrate F, increasing the quality of seedlings of P. elliotii. The use of sewage sludge as substrate for multiplication of earthworms and production of P. elliotti mycorrhizal seedlings is feasible.