USO BENÉFICO DE LODO BIOLÓGICO DE INDÚSTRIA DE CELULOSE E PAPEL PARA PRODUÇÃO DE MUDAS E NA RECUPERAÇÃO DE ÁREAS DEGRADADAS

Abstract

The pulp and paper industry uses water as one of the main inputs in the production process, which is treated using technologies implemented at Effluent Treatment Plants (ETPs). A major challenge with these facilities is the waste generated during the process, known as sludge. Improper disposal of this waste is harmful to the environment. Since sludge is a rich source of organic matter and contains various nutrients, several alternative uses have been proposed. In this context, the aim of this research was to evaluate the use of sludge generated from a pulp and paper industry's wastewater treatment plant to produce seedlings of native Atlantic Forest species for the revegetation and recovery of degraded areas, including post-mining sites. In the greenhouse experiment, five proportions of sludge (0, 5, 10, 20, and 40 percent) were used in the substrate composition for seedling production of four native forest species, and growth, quality indices, biomass, chlorophyll, and nutritional content were assessed. The field experiment was carried out in a post-mining area, incorporating four doses of sludge into the degraded soil (0, 80, 160, and 240 t ha-1). This experiment assessed the soil physical, chemical, and biological attributes, as well as the growth, chlorophyll and nutritional content of the native tree species and the biomass of the green manure species. The alternative use of sludge proved effective for both the nursery production of native tree seedlings and the restoration of degraded soils. This approach offers a promising technique for managing waste disposal, mitigating the negative impacts of improper disposal, promoting soil and environmental recovery, and supporting economic benefits.