Climate and species affect fine root production with long-term fertilization in acidic tussock tundra near Toolik Lake, Alaska
Sullivan, Patrick F.
Rueth, Heather M.
Nadelhoffer, Knute J.
Shaver, Gaius R.
Welker, Jeffrey M.
MetadataShow full item record
KeywordBetula nana; Eriophorum vaginatum; Fertilization; Fine roots; Ingrowth cores; Minirhizotrons; Soil organic carbon; Tussock tundra
Long-term fertilization of acidic tussock tundra has led to changes in plant species composition, increases in aboveground production and biomass and substantial losses of soil organic carbon (SOC). Root litter is an important input to SOC pools, though little is known about fine root demography in tussock tundra. In this study, we examined the response of fine root production and live standing fine root biomass to short- and long-term fertilization, as changes in fine root demography may contribute to observed declines in SOC. Live standing fine root biomass increased with long-term fertilization, while fine root production declined, reflecting replacement of the annual fine root system of Eriophorum vaginatum, with the long-lived fine roots of Betula nana. Fine root production increased in fertilized plots during an unusually warm growing season, but remained unchanged in control plots, consistent with observations that B. nana shows a positive response to climate warming. Calculations based on a few simple assumptions suggest changes in fine root demography with long-term fertilization and species replacement could account for between 20 and 39% of observed declines in SOC stocks.
Author Posting. © The Author(s), 2007. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Oecologia 153 (2007): 643-652, doi:10.1007/s00442-007-0753-8.
Showing items related by title, author, creator and subject.
Bret-Harte, M. Syndonia; Mack, Michelle C.; Shaver, Gaius R.; Huebner, Diane C.; Johnston, Miriam; Mojica, Camilo A.; Pizano, Camila; Reiskind, Julia A. (The Royal Society, 2013-07-08)Fire causes dramatic short-term changes in vegetation and ecosystem function, and may promote rapid vegetation change by creating recruitment opportunities. Climate warming likely will increase the frequency of wildfire ...
Carbon turnover in Alaskan tundra soils : effects of organic matter quality, temperature, moisture and fertilizer Shaver, Gaius R.; Giblin, Anne E.; Nadelhoffer, Knute J.; Thieler, K. K.; Downs, M. R.; Laundre, James A.; Rastetter, Edward B. (2006-02-15)Soils of tundra and boreal ecosystems contain large organic matter stocks, typically as a layer of peat that blankets the underlying mineral soil. Despite the low productivity of northern vegetation, organic matter accumulates ...
Nitrogen dynamics in arctic tundra soils of varying age : differential responses to fertilization and warming Yano, Yuriko; Shaver, Gaius R.; Rastetter, Edward B.; Giblin, Anne E.; Laundre, James A. (2013-03)In the northern foothills of the Brooks Range, Alaska, a series of glacial retreats has created a landscape that varies widely in time since deglaciation (= soil age), from ~10k years to more than 2M years. Productivity ...