Meiofauna reduces bacterial mineralization of naphthalene in marine sediment

• Published in: The ISME Journal 2010-11, Vol.4 (11), p.1421-1430
• Main Authors: Näslund, Johan, Nascimento, Francisco JA, Gunnarsson, Jonas S
• Format: Article
• Language: English
• Subjects: 631/158/2446/2447; 631/158/853; 631/158/855; Abundance; Animal Ecology; Animals; Aromatic hydrocarbons; Bacteria; Bacteria - classification; Bacteria - growth & development; Bacteria - isolation & purification; Bacteria - metabolism; Bacterial Load; Bacterial Typing Techniques; Benthic fauna; Biodegradation; Biodiversity; Biologi; Biology; Biomedical and Life Sciences; Community composition; DNA Fingerprinting; DNA, Bacterial - chemistry; DNA, Bacterial - genetics; DNA, Ribosomal - chemistry; DNA, Ribosomal - genetics; Ecology; Evolutionary Biology; Geologic Sediments - microbiology; Geologic Sediments - parasitology; Hydrocarbons; Invertebrates; Life Sciences; Marine sediments; Meiofauna; Microbial Ecology; Microbial Genetics and Genomics; Microbiology; Microcosms; Mineralization; Molecular Sequence Data; Naphthalene; Naphthalenes - metabolism; NATURAL SCIENCES; NATURVETENSKAP; Nematoda; original-article; Ostracoda; Parasites - growth & development; Polycyclic aromatic hydrocarbons; Polymorphism, Restriction Fragment Length; Radiorespirometry; Restriction fragment length polymorphism; RNA, Ribosomal, 16S - genetics; Sediments; Sequence Analysis, DNA; Terrestrial, freshwater and marine ecology; Terrestrisk, limnisk och marin ekologi; zoologisk ekologi
• ISSN: 1751-7362; 1751-7370
• DOI: 10.1038/ismej.2010.63

The role of sediment-living meiofauna, benthic invertebrates smaller than 1000 μm such as nematodes and ostracods, on the mineralization of naphthalene, a common polycyclic aromatic hydrocarbon (PAH) in marine sediments, was studied in microcosms using radiorespirometry. A method to extract live meiofauna was developed and used in order to experimentally manipulate meiofauna abundance and group diversity. Higher abundances of meiofauna were found to significantly decrease naphthalene mineralization. Furthermore, a change in the bacterial community composition (studied using terminal restriction fragment length polymorphism) was also observed in presence of higher meiofauna abundance, as well as a lower number of cultivable naphthalene-degrading bacteria. The reduced mineralization of naphthalene and the altered bacterial community composition in the presence of increased meiofauna abundance is likely the result of top-down control by meiofauna. This study shows that higher abundances of meiofauna can significantly decrease the microbial mineralization of PAHs such as naphthalene and also significantly modify the bacterial community composition in natural marine sediments.