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Hydrobiologia (2015) 742:107127 DOI 10.1007/s10750-014-1970-x
PRIMARY RESEARCH PAPER
The modern distribution of chironomid sub-fossils (Insecta: Diptera) in Costa Rica and the development of a regional chironomid-based temperature inference model
Jiaying Wu David F. Porinchu Sally P. Horn
Kurt A. Haberyan
Received: 16 November 2013 / Revised: 4 July 2014 / Accepted: 5 July 2014 / Published online: 1 August 2014 Springer International Publishing Switzerland 2014
Abstract Chironomids have been shown to provide robust reconstructions of past temperature change and variability. This is the rst study to assess the contemporaneous relationship between the distribution of sub-fossil chironomids and limnological and climatic parameters in Central America. Here, we describe the distribution of chironomids in a suite of 51 lakes in Costa Rica. We identify environmental variables that account for a statistically signicant amount of variance in midge distribution, and develop a quantitative chironomid-based inference model for mean annual air temperature (MAT). Psectrocladius, which is documented for the rst time in Costa Rica, dominate high-elevation lakes characterized by low MAT and relatively dilute water. Canonical correspondence analysis (CCA) revealed that MAT and conductivity account for large, statistically signicant amounts of variance in the distribution of
chironomids. A chironomid-based inference model for MAT, developed using a partial least squares approach, provided robust performance statistics with a high coefcient of determination and a relatively low root-mean square error. Application of the chironomid-based inference model for MAT to chironomid stratigraphies spanning the Holocene, together with the ecological information provided by this study, will enable us to address many outstanding questions relating to long-term climate and environmental change in the region.
Keywords Paleoclimate Transfer function
Chironomid Costa Rica Paleolimnology Mean
annual air temperature
Introduction
The sediments of lakes and bogs in Costa Rica have been a focus of intensive paleoclimate and paleoenvironmental research, with numerous multi-proxy studies undertaken in recent decades (e.g., Islebe & Hooghiemstra, 1997; Lane et al., 2009a; Lane & Horn, 2013; Taylor et al., 2013). The results from these studies have provided valuable insights into the nature of tropical climate and landscape change during the late Pleistocene and Holocene for this region. For example, much of what is known about late Holocene climate and environmental change in southern Costa Rica comes from detailed analyses of lake sediment cores recovered...