Title
A 6900-year history of landscape modification by humans in lowland Amazonia
Date Issued
01 June 2016
Access level
open access
Resource Type
journal article
Author(s)
Bush M.B.
Correa-Metrio A.
McMichael C.H.
Sully S.
Shadik C.R.
Guilderson T.
Steinitz-Kannan M.
Overpeck J.T.
Florida Institute of Technology
Publisher(s)
Elsevier Ltd
Abstract
A sedimentary record from the Peruvian Amazon provided evidence of climate and vegetation change for the last 6900 years. Piston cores collected from the center of Lake Sauce, a 20 m deep lake at 600 m elevation, were 19.7 m in length. The fossil pollen record showed a continuously forested catchment within the period of the record, although substantial changes in forest composition were apparent. Fossil charcoal, found throughout the record, was probably associated with humans setting fires. Two fires, at c. 6700 cal BP and 4270 cal BP, appear to have been stand-replacing events possibly associated with megadroughts. The fire event at 4270 cal BP followed a drought that caused lowered lake levels for several centuries. The successional trajectories of forest recovery following these large fires were prolonged by smaller fire events. Fossil pollen of Zea mays (cultivated maize) provided evidence of agricultural activity at the site since c. 6320 cal BP. About 5150 years ago, the lake deepened and started to deposit laminated sediments. Maize agriculture reached a peak of intensity between c. 3380 and 700 cal BP. Fossil diatom data provided a proxy for lake nutrient status and productivity, both of which peaked during the period of maize cultivation. A marked change in land use was evident after c. 700 cal BP when maize agriculture was apparently abandoned at this site. Iriartea, a hyperdominant of riparian settings in western Amazonia, increased in abundance within the last 1100 years, but declined markedly at c. 1070 cal BP and again between c. 80 and -10 cal BP.
Start page
52
End page
64
Volume
141
Language
English
OCDE Knowledge area
Ingeniería, Tecnología
Subjects
Scopus EID
2-s2.0-84962786961
Source
Quaternary Science Reviews
ISSN of the container
02773791
Sponsor(s)
We thank the people of the community of Sauce, Peru, for allowing us to investigate their lake. We would like to thank Dr. Jason Curtis of the University of Florida for conducting the nitrogen and carbon assays. This work was supported by grants from the National Science Foundation to Bush and Overpeck (NSF EAR-1303831 , 1303830 ) and NASA Interdisciplinary Research in Earth Science NNX14AD31G to McMichael and Bush.
Sources of information:
Directorio de Producción Científica
Scopus