Directory UMM :Data Elmu:jurnal:S:Soil Biology And Chemistry:Vol32.Issue7.Jul2000:
Soil Biology & Biochemistry 32 (2000) 1015±1024
www.elsevier.com/locate/soilbio
``In situ'' vermicomposting of biological sludges and impacts on
soil quality
G. Masciandaro a, B. Ceccanti a,*, C. Garcia b
a
CNR, Istituto Chimica del Terreno, Area della Ricerca, Loc. S. Cataldo, Via Al®eri, 1-56127 Ghezzano, Pisa, Italy
b
CSIC, Centro de Edafologia y Biologia Aplicada del Segura, Avda. de La Fama s/n Murcia, Spain
Accepted 10 January 2000
Abstract
A laboratory experiment was carried out to study soil quality amelioration through ``in situ'' vermicomposting of biological
sludges. The experiment dealt with the stabilization, through the action of worms (Eisenia fetida ), of ®ve mixtures containing
aerobic and anaerobic biological sludges spread on the soil surface. The results showed that by increasing the percentage of
anaerobic sludge in the mixtures, the number of worms which left the sludge and chose the soil as their habitat increased. The
chemico-structural changes of the sludges left on the soil surface by worms were evaluated through the technique of pyrolysisgas chromatography, which showed that the degrees of mineralization and humi®cation of organic matter were dependent on
the composition of the sludge mixtures. When the amount of aerobic sludge in the mixtures was higher than 50%, a stimulation
of soil microbial metabolism occurred, as demonstrated by the index of metabolic potential (de®ned by dehydrogenase/water
soluble carbon ratio). All treatments increased the percentage of soil total shrinkage area, mostly due to the formation of cracks
of small±medium size (
www.elsevier.com/locate/soilbio
``In situ'' vermicomposting of biological sludges and impacts on
soil quality
G. Masciandaro a, B. Ceccanti a,*, C. Garcia b
a
CNR, Istituto Chimica del Terreno, Area della Ricerca, Loc. S. Cataldo, Via Al®eri, 1-56127 Ghezzano, Pisa, Italy
b
CSIC, Centro de Edafologia y Biologia Aplicada del Segura, Avda. de La Fama s/n Murcia, Spain
Accepted 10 January 2000
Abstract
A laboratory experiment was carried out to study soil quality amelioration through ``in situ'' vermicomposting of biological
sludges. The experiment dealt with the stabilization, through the action of worms (Eisenia fetida ), of ®ve mixtures containing
aerobic and anaerobic biological sludges spread on the soil surface. The results showed that by increasing the percentage of
anaerobic sludge in the mixtures, the number of worms which left the sludge and chose the soil as their habitat increased. The
chemico-structural changes of the sludges left on the soil surface by worms were evaluated through the technique of pyrolysisgas chromatography, which showed that the degrees of mineralization and humi®cation of organic matter were dependent on
the composition of the sludge mixtures. When the amount of aerobic sludge in the mixtures was higher than 50%, a stimulation
of soil microbial metabolism occurred, as demonstrated by the index of metabolic potential (de®ned by dehydrogenase/water
soluble carbon ratio). All treatments increased the percentage of soil total shrinkage area, mostly due to the formation of cracks
of small±medium size (