Long-term warming restructures Arctic tundra without changing net soil carbon storage.
Nature
; 497(7451): 615-8, 2013 May 30.
Article
em En
| MEDLINE
| ID: mdl-23676669
ABSTRACT
High latitudes contain nearly half of global soil carbon, prompting interest in understanding how the Arctic terrestrial carbon balance will respond to rising temperatures. Low temperatures suppress the activity of soil biota, retarding decomposition and nitrogen release, which limits plant and microbial growth. Warming initially accelerates decomposition, increasing nitrogen availability, productivity and woody-plant dominance. However, these responses may be transitory, because coupled abiotic-biotic feedback loops that alter soil-temperature dynamics and change the structure and activity of soil communities, can develop. Here we report the results of a two-decade summer warming experiment in an Alaskan tundra ecosystem. Warming increased plant biomass and woody dominance, indirectly increased winter soil temperature, homogenized the soil trophic structure across horizons and suppressed surface-soil-decomposer activity, but did not change total soil carbon or nitrogen stocks, thereby increasing net ecosystem carbon storage. Notably, the strongest effects were in the mineral horizon, where warming increased decomposer activity and carbon stock a 'biotic awakening' at depth.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Solo
/
Temperatura
/
Carbono
/
Clima Frio
/
Ecossistema
/
Aquecimento Global
/
Ciclo do Carbono
Limite:
Animals
Idioma:
En
Revista:
Nature
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Estados Unidos