title: Microbial diversity of a Mediterranean soil and its changes after biotransformed dry olive residue amendment.
abstract: The Mediterranean basin has been identified as a biodiversity hotspot, about whose soil microbial diversity little is known. Intensive land use and aggressive management practices are degrading the soil, with a consequent loss of fertility. The use of organic amendments such as dry olive residue (DOR), a waste produced by a two-phase olive-oil extraction system, has been proposed as an effective way to improve soil properties. However, before its application to soil, DOR needs a pre-treatment, such as by a ligninolytic fungal transformation, e.g. Coriolopsis floccosa. The present study aimed to describe the bacterial and fungal diversity in a Mediterranean soil and to assess the impact of raw DOR (DOR) and C. floccosa-transformed DOR (CORDOR) on function and phylogeny of soil microbial communities after 0, 30 and 60 days. Pyrosequencing of the 16S rRNA gene demonstrated that bacterial diversity was dominated by the phyla Proteobacteria, Acidobacteria, and Actinobacteria, while 28S-rRNA gene data revealed that Ascomycota and Basidiomycota accounted for the majority of phyla in the fungal community. A Biolog EcoPlate experiment showed that DOR and CORDOR amendments decreased functional diversity and altered microbial functional structures. These changes in soil functionality occurred in parallel with those in phylogenetic bacterial and fungal community structures. Some bacterial and fungal groups increased while others decreased depending on the relative abundance of beneficial and toxic substances incorporated with each amendment. In general, DOR was observed to be more disruptive than CORDOR.
authors: Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas (CSIC), Granada, Spain.
authors: José A
authors: JA
authors: Siles
authors: Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Center for Microbial Ecology, Michigan State University, East Lansing, Michigan, United States of America.
authors: Caio T C C
authors: CT
authors: Rachid
authors: Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas (CSIC), Granada, Spain; Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire, United States of America.
authors: Inmaculada
authors: I
authors: Sampedro
authors: Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas (CSIC), Granada, Spain.
authors: Inmaculada
authors: I
authors: García-Romera
authors: Center for Microbial Ecology, Michigan State University, East Lansing, Michigan, United States of America.
authors: James M
authors: JM
authors: Tiedje
mesh_terms: D061271:Acidobacteria / Q000145:classification / Q000235:genetics / Q000378:metabolism; D001203:Ascomycota / Q000145:classification / Q000235:genetics / Q000378:metabolism; D001487:Basidiomycota / Q000145:classification / Q000235:genetics / Q000378:metabolism; D001711:Biotransformation; D014644:Genetic Variation; D019083:Mediterranean Region; D059013:Microbial Consortia / Q000235:genetics*; D031658:Olea / Q000737:chemistry / Q000382:microbiology*; D010802:Phylogeny; D020560:Proteobacteria / Q000145:classification / Q000235:genetics / Q000378:metabolism; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012987:Soil; D012988:Soil Microbiology; D014866:Waste Products
chemical_list: D012336:RNA, Ribosomal, 16S; D012987:Soil; D014866:Waste Products