Seasonal benthic patterns in a glacial Patagonian fjord: the role of suspended sediment and terrestrial organic matter
Authors:
- E QuirogaEQE Quiroga
- P OrtizPOP Ortiz
- R González-SaldíasRGR González-Saldías
- B ReidBRB Reid
- Fj TapiaFTFj Tapia
- I Pérez-SantosIPI Pérez-Santos
- L RebolledoLRL Rebolledo
- R MansillaRMR Mansilla
- C PinedaCPC Pineda
- I CariICI Cari
- N SalinasNSN Salinas
- A MontielA Montiel
- 15 December 2016
- journal article
- Published by Inter-Research Science Center in Marine Ecology Progress Series
- Vol. 561, 31-50
Abstract
Complex marine-terrestrial interactions characterize Chilean fjords, where benthic communities influence the distribution of organic matter (OM). We examined spatial and seasonal changes in the hydrography, sediment conditions and soft-bottom macrobenthic, meiobenthic, and total microbial biomass in a glacial Patagonian fjord (Martinez Channel, Chile). The transport of a high load of glacial mineral and particulate OM to the fjord in the austral summer coincided with low total live benthic biomass. Multivariate analysis evidenced temporal-related macrofaunal groups influenced by the different environments produced by the advection of sediment transport and terrestrial OM from the Baker River, Chile. The relationships between density/biomass and respiration versus body size varied considerably with distance from major riverine inputs, but the slopes of density size spectra and normalized biomass size spectra were less negative in summer than in winter. Occasional large-scale advective processes in the water column affected sediment conditions and removed surface macrofauna, influencing the slope and intercept of the regression models. In the outer fjord, lateral advection and subsequent sedimentation of terrestrial OM contributed a significant fraction to total OM sediments (<14.76%). Stable carbon isotopes measured in benthic organisms suggest that benthic communities in the inner fjord may assimilate a significant fraction of terrestrial OM via heterotrophic bacteria in contrast to the minor input of terrestrial OM in the outer fjordKeywords
This publication has 80 references indexed in Scilit:
- Modelling benthic oxygen consumption and benthic-pelagic coupling at a shallow station in the southern North SeaEstuarine, Coastal and Shelf Science, 2013
- Size Structure of Marine Soft-Bottom Macrobenthic Communities across Natural Habitat Gradients: Implications for Productivity and Ecosystem FunctionPLOS ONE, 2012
- Organic enrichment and structure of macrobenthic communities in the glacial Baker Fjord, Northern Patagonia, ChileJournal of the Marine Biological Association of the United Kingdom, 2011
- Strong pathways for incorporation of terrestrially derived organic matter into benthic communitiesEstuarine, Coastal and Shelf Science, 2009
- Multi-decadal synthesis of benthic–pelagic coupling in the western arctic: Role of cross-shelf advective processesDeep Sea Research Part II: Topical Studies in Oceanography, 2005
- The distribution of body size in a stream community: one system, many patternsJournal of Animal Ecology, 2005
- Bacterial standing stock, meiofauna and sediment–nutrient characteristics: indicators of benthic disturbance in the Central Indian BasinDeep Sea Research Part II: Topical Studies in Oceanography, 2001
- Ice scour disturbance to benthic communities in the Canadian High ArcticMarine Ecology Progress Series, 1998
- Suspension settling effect on macrobenthos biomass distribution in the Hornsund fjord, SpitsbergenPolar Research, 1987
- Removing Tidal-Period Variations from Time-Series Data Using Low-Pass Digital FiltersJournal of Physical Oceanography, 1982