Nematode Spatial and Ecological Patterns from Tropical and Temperate Rainforests

Authors

Dorota Porazinska, University of Florida-Institute of Food and Agricultural SciencesFollow
Robin Giblin-Davis, University of Florida-Institute of Food and Agricultural Sciences
Thomas Powers, University of Nebraska-LincolnFollow
Kelley Thomas, University of New Hampshire

Document Type

Article

Date of this Version

2012

Citation

Porazinska DL, Giblin-Davis RM, Powers TO, Thomas WK (2012) Nematode Spatial and Ecological Patterns from Tropical and Temperate Rainforests. PLoS ONE 7(9): e44641. doi:10.1371/journal.pone.0044641

Comments

© 2012 Porazinska et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Abstract

Large scale diversity patterns are well established for terrestrial macrobiota (e.g. plants and vertebrates), but not for microscopic organisms (e.g. nematodes). Due to small size, high abundance, and extensive dispersal, microbiota are assumed to exhibit cosmopolitan distributions with no biogeographical patterns. This assumption has been extrapolated from local spatial scale studies of a few taxonomic groups utilizing morphological approaches. Recent molecularly-based studies, however, suggest something quite opposite. Nematodes are the most abundant metazoans on earth, but their diversity patterns are largely unknown. We conducted a survey of nematode diversity within three vertical strata (soil, litter, and canopy) of rainforests at two contrasting latitudes in the North American meridian (temperate: the Olympic National Forest, WA, U.S.A and tropical: La Selva Biological Station, Costa Rica) using standardized sampling designs and sample processing protocols. To describe nematode diversity, we applied an ecometagenetic approach using 454 pyrosequencing. We observed that: 1) nematode communities were unique without even a single common species between the two rainforests, 2) nematode communities were unique among habitats in both rainforests, 3) total species richness was 300% more in the tropical than in the temperate rainforest, 4) 80% of the species in the temperate rainforest resided in the soil, whereas only 20% in the tropics, 5) more than 90% of identified species were novel. Overall, our data provided no support for cosmopolitanism at both local (habitats) and large (rainforests) spatial scales. In addition, our data indicated that biogeographical patterns typical of macrobiota also exist for microbiota.