Industrial and urban organic wastes increase soil microbial activity and biomass

Abstract

SUMMARYMicrobial processes have been used as indicators of soil quality, due to the high sensitivity to small changes in management to evaluate, e.g., the impact of applying organic residues to the soil. In an experiment in a completely randomized factorial design 6 x 13 + 4, (pot without soil and residue or absolute control) the effect of following organic wastes was evaluated: pulp mill sludge, petrochemical complex sludge, municipal sewage sludge, dairy factory sewage sludge, waste from pulp industry and control (soil without organic waste) after 2, 4, 6, 12, 14, 20, 28, 36, 44, 60, 74, 86, and 98 days of incubation on some soil microbial properties, with four replications. The soil microbial activity was highly sensitive to the carbon/nitrogen ratio of the organic wastes. The amount of mineralized carbon was proportional to the quantity of soil-applied carbon. The average carbon dioxide emanating from the soil with pulp mill sludge, corresponding to soil basal respiration, was 0.141 mg C-CO 2 100 g -1 soil h -1 . This value is 6.4 times higher than in the control, resulting in a significant increase in the metabolic quotient from 0.005 in the control to 0.025 mg C-CO 2 g -1 C mic h -1 in the soil with pulp mill sludge. The metabolic quotient in the other treatments did not differ from the control (p < 0.01), demonstrating that these organic wastes cause no disturbance in the microbial community.Index terms: microbial respiration, microbial carbon, microbial nitrogen, metabolic quotient, organic sludge.(1) Part of the dissertation of the first author, for a post-graduate degree in Agricultural Sciences, 2, 4, 6, 12, 14, 20, 28, 36, 44, 60, 74, 86

Changes on microbial C and enzyme activities in soil with amendment of composted tannery sludge after 9 years

“…It can be related with the C and nutrient sources released by CTS and also the better soil conditions found with the amendment of these rates. This finding agrees with Boechat et al (2012) who evaluated the effect of industrial and organic waste on soil and found an increase in soil microbial biomass with the application of the wastes. Previously, Bouzaiane et al (2007) evaluated the effect of municipal solid waste compost on soil microbial biomass C and N, and found an improvement in the size of soil microbial biomass with the application of 40 t ha −1 of compost.…”

“…Soil microorganisms present high sensitivity to the soil conditions and also to the environmental impact of municipal and industrial wastes (Boechat et al 2012;Sousa et al 2017;Miranda et al 2018). In these conditions, the evaluation of microbial C is considered as a suitable and robust method for measuring the effect on soil microorganisms (Lopes et al 2013).…”

Filter Cake, Residue of the Sugarcane Industry - A Evaluation by Slow Pyrolysis

“…orgânicos utilizados em quantidades acima do potencial do solo, ou das necessidades das culturas, podem causar problemas ambientais associados a perda de nitrogênio, ao aumento de patógenos e metais pesados, a acidificação ou salinização dos solos agrícolas e ainda podem promover a imobilização do nitrogênio, quando incorporado diretamente no solo, devido à estimulação da atividade microbiana nativa. [17][18][19] A disponibilidade e o alto teor de matéria orgânica da torta de filtro mostra a potencialidade para o estudo de seu aproveitamento por pirólise lenta, na obtenção do biocarvão e suas diversas possibilidades de aplicação.…”

<b>Quantification and analysis of the viability of (oo)cysts of pathogenic protozoa in sewage sludge

“…Studies have demonstrated its influence on chemical and physical properties of the soil, as it increases the water holding capacity, the resistance to erosion, improves soil fertility and enhances microbial activity (Boechat, Santos, Accioly, Bomfim, & Santos, 2012). Thus, it has been used for recovery of degraded areas (Bittencourt, Serrat, Aisse, Marin, & Simão, 2012, Sampaio et al, 2012, as a substrate for seedling production (Santos, Kunz, Caldeira, Azevedo, & Rangel, 2014), and in areas cultivated with corn (Barros, Andreoli, Souza Junior, & Costa, 2011), sugar cane (Franco, Marques, & Melo, 2008), eucalyptus (Barreiros, Gonçalves, Sansígolo, & Poggiani, 2007), among other crops.…”