Decomposition rate and enzymatic activity of composted municipal waste and poultry manure in the soil in a biofuel crops field.
BACKGROUND
Biofuel crops are gaining importance because of the need to replace non-renewable sources. Also, due to the increasing amounts of wastes generated, there is the need to recycle them to the soil, both to fertilize crops and to improve soil physical properties through organic matter increase and microbiological changes in the rhizosphere. We therefore studied the influence of six biofuel crops (elephant grass, giant cane, sugarcane, blue gum, black cottonwood, willow) on the decomposition rate and enzymatic activity of composted municipal solid waste and poultry manure. Organic amendments were incubated in the field (litterbag method), buried near each plant or bare soil. Biomass decrease and dehydrogenase, urease and acid phosphatase level in amendments was monitored over a 180-day period. Soil under the litterbags was analysed for the same enzymatic activity and organic matter fractions (last sampling). After 365 days, a fractionation of organic matter was carried out in both amendments and soil under the litterbags.


RESULTS
For compost, willow and sugarcane generally led to the greatest enzymatic activity, at the end of the experiment. For manure, dehydrogenase activity decreased sharply with time, the smallest value near sugarcane, while phosphatase and urease generally presented the highest values, at the beginning or after 90 days' incubation. Clustering showed that plant species could be grouped based on biomass and enzymes measured over time.


CONCLUSIONS
Plant species influenced the decomposition rate and enzymatic activities of the organic amendments. Overall, mineralization of both amendments was associated with a greater urease activity in soils. Dehydrogenase activity in manure was closely associated with urease activity. © 2016 Society of Chemical Industry.
Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017, Lisbon, Portugal.
Cláudia Marques-Dos-Santos
CM
Cordovil
Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017, Lisbon, Portugal.
Amarilis
A
de Varennes
Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017, Lisbon, Portugal.
Renata Machado Dos Santos
RM
Pinto
Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017, Lisbon, Portugal.
Tiago Filipe
TF
Alves
Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017, Lisbon, Portugal.
Pedro
P
Mendes
Research Group on Water Resources and Environmental Sanitation, Western Paraná State University, UNIOESTE/Cascavel/ CCET/PGEAGRI, 85819-110, Cascavel, PR, Brazil.
Sílvio César
SC
Sampaio
D000135:Acid Phosphatase / Q000737:chemistry*; D000818:Animals; D055162:Biocatalysis; D056804:Biofuels / Q000032:analysis*; D018556:Crops, Agricultural / Q000737:chemistry*; D008372:Manure / Q000032:analysis*; D010088:Oxidoreductases / Q000737:chemistry*; D011200:Poultry; D012037:Refuse Disposal / Q000379:methods*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry; D014510:Urease / Q000737:chemistry*
D056804:Biofuels; D008372:Manure; D012987:Soil; D012989:Soil Pollutants; D010088:Oxidoreductases; D000135:Acid Phosphatase; D014510:Urease
dehydrogenase; litterbags; organic amendments; phosphatase; soil; urease