Abstract
Mineralisation of organic detritus in the marine surficial sediments generates a flux of dissolved inorganic nutrient between the sediment and overlying water column. This is a key process in the marine ecosystem, which links the food webs of the sea-floor and the overlying water-column, and is potentially affected by a range of interacting environmental and sedimentary factors. Here, we use General Additive Models (GAM) to statistically disentangle some of the factors controlling the seasonal and spatial variability in nutrients and oxygen fluxes in a field dataset collected in the North Sea off the northeast coast of Scotland. We show that sediment grain size, turbidity due to sediment re-suspension, temperature, and sediment chlorophyll content were the key factors affecting oxygen, ammonia, and silicate fluxes. However, phosphate fluxes were only related to suspended sediment concentrations, whilst nitrate fluxes showed no clear relationship to any of the expected drivers of change, probably due to the effects of denitrification. Our analyses show that the stoichiometry of nutrient regeneration in the ecosystem is not necessarily constant and may be affected by combinations of processes.
| Original language | English |
|---|---|
| Article number | 65 |
| Pages (from-to) | 1-17 |
| Number of pages | 17 |
| Journal | Frontiers in Earth Science |
| Volume | 4 |
| DOIs | |
| Publication status | Published - 8 Jun 2016 |
Bibliographical note
AcknowledgmentsOur thanks to the captain and crew of the research vessel “Temora,” and to our colleagues who have assisted with various aspects of the work at sea and in the laboratory, especially John Dunn and Steve Hay. Thanks also to Doug Webster for his help with the design and realization of the “falling head/constant head” system to measure sediment permeability.
Funding
This work was co-funded by the Marine Scotland—Science Laboratory Aberdeen, and University of Aberdeen, through the joint Fisheries Research Fund. In addition, the authors acknowledge the support of the MASTS pooling initiative (The Marine Alliance for Science and Technology for Scotland) in the completion of this study. MASTS is funded by the Scottish Funding Council (grant reference HR09011) and contributing institutions.
Keywords
- benthic mineralization
- sediment oxygen flux
- sediment nutrient fluxes
- temperature
- chlorophyll-a
- permeability
- turbidity
- general additive models
Access to Document
- Statistical Modeling of Variability in Sediment-Water Nutrient and Oxygen Fluxes
© 2016 Serpetti, Witte and Heath. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY): http://creativecommons.org/licenses/by/4.0/ The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.