Paleoenvironmental Change Research Group

Contact Info:

Dr. Chad Lane

Department of Earth and Ocean Sciences

Phone: (910) 962-3466 Fax: (910) 962-3490

e-mail: lanec@uncw.edu

Developing a Network of n-Alkane Hydrogen Isotope Records in Costa Rica to Elucidate Drivers and Impacts of Holocene Droughts (NSF-GSS 1660185)

This project will address patterns and drivers of past droughts and their effects on humans and the biosphere. The researchers will analyze lake-sediment cores to develop records of precipitation variability associated with past shifts in major drivers of atmospheric circulation that influenced the broader circum-Caribbean region, including the U.S. Gulf Coast. The precipitation records will be compared to evidence of past human activity and biomass burning in lake watersheds, to explore local consequences of regional shifts in atmospheric drivers. The work will form the foundation for an expanded network of precipitation reconstructions across the region that will allow examination of processes at a larger spatial scale and of additional drivers. The project will provide experience in multi-laboratory collaborative research to four faculty and ten or more graduate and undergraduate students. Results from project activities will be broadly disseminated in publications and presentations. The researchers will share scientific knowledge of past environmental change with K-12 students and teachers in Tennessee and North Carolina through outreach projects that will include hands-on activities and authentic research.

The researchers will develop precipitation records using compound-specific hydrogen isotope analyses of n-alkanes in lipids in sediment cores from five lakes along two transects that cross climate and ecosystem regions. Hydrogen isotope analysis of lipids in sediment cores is an alternative to oxygen isotope analysis of biogenic carbonates that can be applied in a wide variety of lakes, making possible the development of a network of sites using the same precipitation proxy. The hydrogen isotope records will be produced from existing cores from lakes in Costa Rica, and will serve as the western anchor in a larger network of precipitation records that the researchers plan to develop through the broader circum-Caribbean region, including the U.S. Gulf Coastal Plain. The hydrogen isotope analyses will document the geography of multi-decadal drought during the Terminal Classic Drought (~1200-850 cal yr BP), the Little Ice Age (~500-100 cal yr BP), and at other times, and reveal whether these were exceptional or outlier droughts for the Holocene as a whole. Comparison with local paleoenvironmental and archaeological evidence will show how past droughts affected vegetation, fire regimes, and prehistoric agriculture. This project is being conducted in collaboration with Dr. Sally Horn (University of Tennessee) and Doug Gamble (UNCW).

 

 

 

Presentations and Publications Related to this Project

Paleolimnological records of vegetation, climate, and fire from Jones and Singletary Lake (Carolina Bays) Spencer et al. 2017; Lane et al. 2018

Climate and environmental change in coastal Portugal Taylor et al. 2018

Modern n-alkane abundances and isotopic values in vegetaiton of a gymnosperm-dominated ecosystem Lane 2017

Confirmation of tropical strom deposits using stable oxygen isotope analyses of ostracods Lane et al. 2017; LeBlanc et al. 2017

Climate and fire history from Wolf Lake, Adirondacks, New York Stager et al. 2017

Evidence of minimal pre-aging of alkanes in a small tropical watershed Lane et al. 2016

Bioluminescence in Mangrove Lagoon, St. Croix Reidhaar et al. 2016

Sedimentary evidence of mid-Holocene aridity from a North Carolina wetland Tanner et al. 2015

The Terminal Classic Drought (TCD) in the Caribbean Antilles Lane et al. 2014

Paleoenvironmental history of bioluminescent Laguna Grande, Puerto Rico Lane et al. 2013

Nutrient impacts on heterotrophic biofilm processing of dissolved organic carbon Lane et al. 2013

Temperature impacts on carbon metabolism in boreal forest soils Li et al. 2012;Ziegler et al. 2013;Li et al. 2013

Little Ice Age climate in the mid-elevations of the Dominican Republic Lane et al. 2011

Compound-specific isotope analysis of lake sediments from Lago de las Morrenas, Costa Rica Lane et al. 2011; Lane and Horn 2013

Modern maize pollen deposition in Wisconsin lake sediments Lane et al. 2010

Bulk and compound-specific carbon isotope analysis of marsh plants and sediments Tanner et al. 2010

Natural and anthropogenic environmental change in the Dominican Republic Lane et al. 2009

Detection and analysis of prehistoric maize agriculture using bulk stable carbon isotope analysis of lake and swamp sediments Lane et al. 2004; Lane et al 2008; Lane et al. 2009

Pollen evidence of prehistoric maize agriculture in the Dominican Republic Lane et al. 2008

Applicability of Rapaport's Rule to tree species in North America Lane 2007

Laboratory production of charcoal specimens from vouchered plant samples Orvis et al. 2005