Novel responses of diatoms in neotropical mountain lakes to indigenous and post-European occupation

Velez, Maria I.; Salgado, Jorge; Brenner, Mark; Hooghiemstra, Henry; Escobar, Jaime; Boom, Arnoud; Bird, Broxton; Curtis, Jason H.; Temoltzin-Loranca, Yunuen; Patino, Luisa Fernanda; Gonzalez-Arango, Catalina; Metcalfe, Sarah E.; Simpson, Gavin L.; Velasquez, Cesar (2021). Novel responses of diatoms in neotropical mountain lakes to indigenous and post-European occupation. Anthropocene, 34, p. 100294. Elsevier 10.1016/j.ancene.2021.100294

[img] Text
2021_Anthropocene_34_100294.pdf - Published Version
Restricted to registered users only
Available under License Publisher holds Copyright.

Download (3MB) | Request a copy

How Indigenous peoples and European settlers transformed terrestrial ecosystems in the Americas is well evidenced in the literature, but far less is known about how aquatic ecosystems changed. This study examined diatom records from sediment cores from paleoclimate studies in mountain lakes of Guatemala, Panama, and Colombia, in order to clarify the long-term human influences on the ecology of these lakes. We focused on two aspects of beta diversity in identified diatom zones: species turnover and variation in relative abundances of species. All records displayed a single diatom zone or cluster of zones with assemblages that had no close analogues in the past. The ages of these distinctive assemblages varied from post-European to 5000 cal yr BP. Most novel assemblages comprised moderately motile, non-planktonic, single-celled diatoms, associated with disturbed, productive environments. Archaeological data and pollen records pointed to the onset of intensification of human activities as the main driver behind the changes in diatoms. Maximum depth exerted control on how diatom communities responded to anthropogenic stressors. In shallower lakes, diatom assemblages transitioned gradually over time into their current novel composition. In deeper lakes, assemblages displayed slight fluctuations before shifting to their current condition. Differences between the two lake groups likely resulted from a more complete water-column mixing and higher rates of nutrient cycling in the shallow lakes, which led to a more rapid response of the diatoms to environmental changes. The shift to novel recent diatom assemblages suggests that these lakes now display ecosystem characteristics with no past analogues, and that they have lost their capacity to resist change or recover from stressors, jeopardizing the future of mountain water resources. (C) 2021 Elsevier Ltd. All rights reserved.

Item Type:

Journal Article (Original Article)

Division/Institute:

10 Strategic Research Centers > Oeschger Centre for Climate Change Research (OCCR)
08 Faculty of Science > Institute of Geography
08 Faculty of Science > Department of Biology > Institute of Plant Sciences (IPS) > Palaeoecology
08 Faculty of Science > Department of Biology > Institute of Plant Sciences (IPS)

UniBE Contributor:

Temoltzin Loranca, Yunuen

Subjects:

500 Science > 580 Plants (Botany)
900 History > 910 Geography & travel

ISSN:

2213-3054

Publisher:

Elsevier

Language:

English

Submitter:

Peter Alfred von Ballmoos-Haas

Date Deposited:

15 Jul 2021 12:21

Last Modified:

18 Jul 2021 03:06

Publisher DOI:

10.1016/j.ancene.2021.100294

Uncontrolled Keywords:

Anthropocene; Novel diatom assemblages; European colonization; Holocene; Lake depth; Neotropics

BORIS DOI:

10.48350/157299

URI:

https://boris.unibe.ch/id/eprint/157299

Actions (login required)

Edit item Edit item
Provide Feedback