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Freeze-lysable inorganic nutrients in intertidal sediments: dependence on microphytobenthos abundance

2010; Inter-Research; Volume: 403; Linguagem: Inglês

10.3354/meps08470

1616-1599

Emilio García‐Robledo, Alfonso Corzo, Sokratis Papaspyrou, Juan Luís Jiménez‐Arias, D. Villahermosa,

Marine Bivalve and Aquaculture Studies

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 403:155-163 (2010) - DOI: https://doi.org/10.3354/meps08470 Freeze-lysable inorganic nutrients in intertidal sediments: dependence on microphytobenthos abundance Emilio García-Robledo1,*, Alfonso Corzo1, Sokratis Papaspyrou1,2, Juan L. Jiménez-Arias1, Desirée Villahermosa1 1Departamento Biología, Facultad de Ciencias del Mar y Ambientales, Universidad de Cádiz, Pol. Río San Pedro s/n, 11510- Puerto Real, Cádiz, Spain 2Instituto de Ciencias Marinas de Andalucía (CSIC), Pol. Rio San Pedro s/n, 11510 Puerto Real, Cádiz, Spain *Email: emilio.garcia@uca.es ABSTRACT: Freezing is a common treatment for the preservation of sediment samples. To test the role of microphytobenthos (MPB) abundance in the release of intracellular nutrients to the pore water due to cell breakage after freezing, referred to as freeze-lysable inorganic nutrients (FL-IN), parallel extractions were carried out from intertidal sediment cores collected in winter and summer from Cádiz Bay. After the determination of net production and dark respiration rates with O2 microsensors, sediment cores were subcored and sliced into several layers. The samples were divided into 2 fractions; the first was centrifuged to extract pore water (fresh) and the other was frozen at –80°C, thawed and centrifuged to extract pore water after freezing. NO2–, NO3–, NH4+ and PO43– were measured in the pore water extracted by both procedures. Chlorophylls a and c were extracted from the same sediment fractions. Freezing produced a significant increase in the pore water concentrations of all inorganic nutrients. Therefore, if the variable of interest is the inorganic nutrient concentration, pore water should be extracted from fresh samples. In addition, FL-IN correlated significantly with chlorophylls a and c (p < 0.01), r2 ranged from 0.54 for NO3– to 0.94 for NH4+, indicating that most FL-IN were released from MPB biomass. The relationships between chlorophyll a and FL-IN in winter and summer were significantly different, suggesting that nutrient accumulation by MPB changes seasonally and might affect nutrient cycling in intertidal sediments. KEY WORDS: Microphytobenthos · Microbenthos · Freeze-lysable inorganic nutrients · Pore water nutrients · Intertidal sediments · Benthic microalgae · Sediment preservation Full text in pdf format PreviousNextCite this article as: García-Robledo E, Corzo A, Papaspyrou S, Jiménez-Arias JL, Villahermosa D (2010) Freeze-lysable inorganic nutrients in intertidal sediments: dependence on microphytobenthos abundance. Mar Ecol Prog Ser 403:155-163. https://doi.org/10.3354/meps08470 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 403. Online publication date: March 22, 2010 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2010 Inter-Research.