Diatoms and other siliceous indicators track the ontogeny of a bofedal (wetland) ecosystem in the Peruvian Andes

• Main Authors: King, Connor, Michelutti, Neal, Meyer-Jacob, Carsten, Bindler, Richard, Tapia, Pedro, Grooms, Christopher, Smol, John P.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: University of Toronto 2021
• Subjects: ice core
• Online Access: http://hdl.handle.net/1807/106800; http://www.nrcresearchpress.com/doi/abs/10.1139/cjb-2020-0196

Recent warming in the Andes is affecting the region’s water resources including glaciers and lakes, which supply water to tens of millions of people downstream. High altitude wetlands, known locally as bofedales, are an understudied Andean ecosystem despite their key role in carbon sequestration, maintaining biodiversity, and regulating water flow. Here, we analyze subfossil diatom assemblages and other siliceous bioindicators preserved in a peat core collected from a bofedal in Peru’s Cordillera Vilcanota. Basal radiocarbon ages show the bofedal likely formed during a wet period of the Little Ice Age (1520-1680 CE), as inferred from nearby ice core data. The subfossil diatom record is marked by several dynamic assemblage shifts documenting a hydrosere succession from an open-water system to mature peatland. The diatoms appear to be responding largely to changes in hydrology that occur within the natural development of the bofedal, but also to pH and possibly nutrient enrichment from grazing animals. The rapid peat accretion recorded post-1950 at this site is consistent with recent peat growth rates elsewhere in the Andes. Given the many threats to Peruvian bofedales including climate change, overgrazing, peat extraction, and mining, these baseline data will be critical to assessing future change in these important ecosystems. The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author.