title: Differences in soil micro-eukaryotic communities over soil pH gradients are strongly driven by parasites and saprotrophs.
abstract: A recent large-scale assessment of bacterial communities across a range of UK soil types showed that bacterial community structure was strongly determined by soil pH. We analysed a data set of eukaryotic 454 sequencing 18S rDNA from the surveyed samples and showed significant differences in eukaryotic assemblages according to pH class, mostly between low pH and higher pH soils. Soil eukaryote communities (per sample) differed most at the taxonomic rank approximating to order level. Taxonomies assigned with the Protist Ribosomal Reference and the Silva 119 databases were taxonomically inconsistent, mostly due to differing 18S annotations, although general structure and composition according to pH were coherent. A relatively small number of lineages, mostly putative parasitic protists and fungi, drive most differences between pH classes, with weaker contributions from bacterivores and autotrophs. Overall, soil parasites included a large diversity of alveolates, in particular apicomplexans. Phylogenetic analysis of alveolate lineages demonstrates a large diversity of unknown gregarines, novel perkinsids, coccidians, colpodellids and uncharacterized alveolates. Other novel and/or divergent lineages were revealed across the eukaryote tree of life. Our study provides an in-depth taxonomic evaluation of micro-eukaryotic diversity, and reveals novel lineages and insights into their relationships with environmental variables across soil gradients.
authors.affiliation: Department of Life Sciences, the Natural History Museum, Cromwell Road, London, SW7 5BD, UK.
authors.forename: A Ö C
authors.initials: AÖ
authors.lastname: Dupont
authors.affiliation: Centre for Ecology & Hydrology, Benson Lane, Crowmarsh Gifford, Wallingford, OX10 8BB, UK.
authors.forename: R I
authors.initials: RI
authors.lastname: Griffiths
authors.affiliation: Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, Berkshire, SL5 7PY, UK.
authors.forename: T
authors.initials: T
authors.lastname: Bell
authors.affiliation: Department of Life Sciences, the Natural History Museum, Cromwell Road, London, SW7 5BD, UK.|Cefas, Barrack Road, The Nothe, Weymouth, DT4 8UB, UK.
authors.forename: D
authors.initials: D
authors.lastname: Bass
mesh_terms: D000818:Animals; D044822:Biodiversity; D056890:Eukaryota / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D005658:Fungi / Q000235:genetics / Q000302:isolation & purification; D006863:Hydrogen-Ion Concentration; D010271:Parasites / Q000235:genetics / Q000302:isolation & purification; D010802:Phylogeny; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D012987:Soil / Q000737:chemistry* / Q000469:parasitology*; D012988:Soil Microbiology
chemical_list: D012337:RNA, Ribosomal, 18S; D012987:Soil