Polyethylene and bioplastic biodegradation in soil

  • Gustavo Tadeu Alvarenga Marques de Souza Universidade de Taubaté (UNITAU), Taubaté, SP, Brasil Programa de Pós-Graduação em Ciências Ambientais
  • Paulo Fortes Neto Universidade de Taubaté (UNITAU), Taubaté, SP, Brasil Programa de Pós-Graduação em Ciências Ambientais
  • Nara Lúcia Perondi Fortes Universidade de Taubaté (UNITAU), Taubaté, SP, Brasil Programa de Pós-Graduação em Ciências Ambientais
  • Elizabeth da Costa Neves Fernandes de Almeida Duarte Universidade de Lisboa, Lisboa, Portugal Instituto Superior de Agronomia
  • Raquel Alexandra Cardoso Costa Universidade de Lisboa, Lisboa, Portugal Instituto Superior de Agronomia
  • Artur Figueiredo Saraiva Universidade de Lisboa, Lisboa, Portugal Instituto Superior de Agronomia
Keywords: CO2 evolution, decomposition, microbial activity

Abstract

After being used as soil cover, polyethylene film is burned with the cultural remains or incorporated into the soil, since its removal from the field entails labor costs. An alternative to avoid this problem is to replace the polyethylene with bioplastic, because after use the bioplastic can be incorporated into the soil. This study therefore evaluated the biodegradability of polyethylene and bioplastic in soil by means of mass loss, C-CO2 release and bacterial counting. In order to estimate the loss of mass, polyethylene and bioplastic samples were placed in nylon bags (2 mm) and buried at 0.20 m depth of soil and the films were periodically weighed (30, 60, 90 and 120 days) to evaluate the loss Of mass. The C-CO2 emissions and the bacterial colony forming unit count were determined in soil samples incubated with polyethylene, bioplastic and cellulose. The biodegradation of the bioplastic estimated by the loss of mass was 37% and of the polyethylene was 1.2%. The release of C‑CO2 and the number of bacteria were higher in the soils incubated with cellulose and bioplastic.


Published
10/12/2016
Section
Special