TY - JOUR
T1 - Seasonal benthic patterns in a glacial Patagonian fford
T2 - The role of suspended sediment and terrestrial organic matter
AU - Quiroga, Eduardo
AU - Ortiz, Paula
AU - González-Saldías, Rodrigo
AU - Reid, Brian
AU - Tapia, Fabián J.
AU - Pérez-Santos, Iván
AU - Rebolledo, Lorena
AU - Mansilla, Rodrigo
AU - Pineda, Carlos
AU - Cari, Ilia
AU - Salinas, Nicole
AU - Montiel, Américo
AU - Gerdes, Dieter
N1 - Publisher Copyright:
© Inter-Research 2016.
PY - 2016/12/15
Y1 - 2016/12/15
N2 - Complex marine-terrestrial interactions characterize Chilean ffords, 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 fford (Martinez Channel, Chile). The transport of a high load of glacial mineral and particulate OM to the fford 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 fford, 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 fford may assimilate a significant fraction of terrestrial OM via heterotrophic bacteria in contrast to the minor input of terrestrial OM in the outer fford.
AB - Complex marine-terrestrial interactions characterize Chilean ffords, 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 fford (Martinez Channel, Chile). The transport of a high load of glacial mineral and particulate OM to the fford 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 fford, 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 fford may assimilate a significant fraction of terrestrial OM via heterotrophic bacteria in contrast to the minor input of terrestrial OM in the outer fford.
KW - Macrofauna
KW - Meiofauna
KW - Stable isotopes
KW - Total microbial biomass
KW - Trophic structure
UR - http://www.scopus.com/inward/record.url?scp=85006337947&partnerID=8YFLogxK
U2 - 10.3354/meps11903
DO - 10.3354/meps11903
M3 - Article
AN - SCOPUS:85006337947
SN - 0171-8630
VL - 561
SP - 31
EP - 50
JO - Marine Ecology Progress Series
JF - Marine Ecology Progress Series
ER -