Premium
Testate amoebae as a proxy for reconstructing Holocene water table dynamics in southern Patagonian peat bogs
Author(s) -
VAN BELLEN SIMON,
MAUQUOY DMITRI,
PAYNE RICHARD J.,
ROLAND THOMAS P.,
DALEY TIM J.,
HUGHES PAUL D. M.,
LOADER NEIL J.,
STREETPERROTT F. ALAYNE,
RICE EMMA M.,
PANCOTTO VERÓNICA A.
Publication year - 2014
Publication title -
journal of quaternary science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.142
H-Index - 94
eISSN - 1099-1417
pISSN - 0267-8179
DOI - 10.1002/jqs.2719
Subject(s) - bog , testate amoebae , peat , water table , transect , sphagnum , geology , southern hemisphere , hydrology (agriculture) , proxy (statistics) , physical geography , holocene , ecology , environmental science , climatology , groundwater , geography , oceanography , biology , statistics , mathematics , geotechnical engineering
Testate amoebae are abundant and diverse in Sphagnum peat bogs and have been used extensively as indicators of past water table depths. Although these unicellular protists are widely dispersed with globally similar hydrological preferences, regional variations in communities demand region‐specific transfer functions. Here we present the first transfer function for southern Patagonian bogs, based on 154 surface samples obtained from transects in five bogs sampled in 2012 and 2013. Significant variance was explained by pH, electrical conductivity and, in particular, water table depth. Transfer functions for water table were constructed using weighted averaging and evaluated by cross‐validation and independent test sets. The optimal transfer function has predictive ability, but relatively high prediction errors given the wide range in sampled water tables. The use of independent test sets, as well as cross‐validation, allows a more rigorous assessment of model performance than most previous studies. For a subset of locations we compare surface and subsurface samples to demonstrate significant differences in community composition, possibly due to vertical zonation. Our results provide the first quantification of hydrological optima and tolerances for several rare species, which may include Southern Hemisphere endemics and pave the way for palaeohydrological reconstructions in southern Patagonian bogs.