DOI: 10.1016/j.gloplacha.2013.09.014
论文题名: A hypothesis linking chrysophyte microfossils to lake carbon dynamics on ecological and evolutionary time scales
作者: Wolfe A.P. ; Siver P.A.
刊名: Global and Planetary Change
ISSN: 0921-8198
出版年: 2013
卷: 111 起始页码: 189
结束页码: 198
语种: 英语
英文关键词: Chrysophytes
; Eocene
; Global environmental change
; Lake carbon dynamics
; Paleolimnology
; Siliceous microfossils
Scopus关键词: Carbon dynamics
; Chrysophytes
; Eocene
; Global environmental change
; Microfossils
; Algae
; Carbon
; Ecology
; Lakes
; Paleolimnology
; Sediments
; Carbon dioxide
; carbon cycle
; carbon dioxide
; cyst
; dissolved organic matter
; Eocene
; fossil record
; glacial lake
; global change
; lacustrine deposit
; lake dynamics
; microalga
; microfossil
; oligotrophic environment
; paleolimnology
; pH
; timescale
; New England
; United States
英文摘要: Chrysophyte algae are common in the plankton of oligotrophic lakes and produce a rich microfossil record of siliceous cysts and scales. Paleolimnological investigations and phytoplankton records suggest that chrysophyte populations are increasing in a wide range of boreal and arctic lakes, ultimately representing one component of the limnological response to contemporary global changes. However, the exact mechanisms responsible for widespread increases of chrysophyte populations remain elusive. We hypothesize that recent increases in chrysophytes are related to rising pCO2 in lakes, in part because these algae lack carbon concentrating mechanisms and therefore rely on diffusive entry of CO2 to Rubisco during photosynthesis. We assessed the abundance of modern sediment chrysophyte microfossils in relation to summer CO2 relative saturation in 46 New England (USA) lakes, revealing significant positive relationships for both cysts and scales. These observations imply that correlations between chrysophytes and limnological conditions including low pH, oligotrophy, and elevated dissolved organic matter are ultimately underscored by the high pCO2 associated with these conditions. In lakes where chrysophyte populations have expanded over recent decades, we infer that increasingly heterotrophic conditions with respect to CO2 have stimulated production by these organisms. This linkage is supported by the remarkable abundance and diversity of chrysophytes from middle Eocene lake sediments, deposited under atmospheric CO2 concentrations significantly higher than present. The Eocene assemblages suggest that any chrysophyte-CO2 connection borne out of results from modern and sub-recent sediments also operated on evolutionary time scales, and thus the absence of carbon concentrating mechanisms appears to be an ancient feature within the group. Chrysophyte microfossils may potentially provide important insights concerning the temporal dynamics of carbon cycling in aquatic ecosystems. © 2013 Elsevier B.V. URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84885934032&doi=10.1016%2fj.gloplacha.2013.09.014&partnerID=40&md5=d5b521e02315ffb1ec3ceb366436dae6
Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/11104
Appears in Collections: 全球变化的国际研究计划
There are no files associated with this item.
作者单位: Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, AB T6G 2E3, Canada
Recommended Citation:
Wolfe A.P.,Siver P.A.. A hypothesis linking chrysophyte microfossils to lake carbon dynamics on ecological and evolutionary time scales[J]. Global and Planetary Change,2013-01-01,111.