Martin Arford
Assistant Professor of Geography Appointed to SVSU in 2005
M. S. University of Tennessee
B. S. Indiana University of Pennsylvania
PAPER
with Jason Graham and Sally P. Horn (both University of Tennessee). "A High-Resolution Macroscopic Charcoal Record from Laguna Martínez, Costa Rica." Annual meeting of the Association of American Geographers, San Francisco, California, April 2007.
We analyzed macroscopic charcoal in a 5 meter lake sediment core from Laguna Martínez in northwestern Costa Rica as a complement to prior analyses of pollen and microscopic charcoal. This lake (10.642 N, 85.197 W, 340 m elevation) is located in an area of seasonally dry tropical forests on the lower slope of Miravalles volcano; it formed about 8,000 years ago in conjunction with pyroclastic flows from Miravalles volcano. Pollen analysis revealed the earliest evidence of maize agriculture in Costa Rica (4760 ± 40 yr BP). Macroscopic charcoal was sampled at contiguous 1 cm intervals, disaggregated and sieved through 250 and 500 micrometer screens. Macroscopic charcoal concentrations varied by over two orders of magnitude between samples, and nearly mirrored microscopic concentrations. This reinforced our interpretation that microscopic charcoal in the Laguna Martinez sediments represents local fires, in contrast with most other sediment charcoal studies.