Details
| Originalsprache | Englisch |
|---|---|
| Seiten (von - bis) | 567-582 |
| Seitenumfang | 16 |
| Fachzeitschrift | Global biogeochemical cycles |
| Jahrgang | 29 |
| Ausgabenummer | 5 |
| Publikationsstatus | Veröffentlicht - 1 Mai 2015 |
Abstract
Soil N availability is constrained by the breakdown of N-containing polymers such as proteins to oligopeptides and amino acids that can be taken up by plants and microorganisms. Excess N is released from microbial cells as ammonium (N mineralization), which in turn can serve as substrate for nitrification. According to stoichiometric theory, N mineralization and nitrification are expected to increase in relation to protein depolymerization with decreasing N limitation, and thus from higher to lower latitudes and from topsoils to subsoils. To test these hypotheses, we compared gross rates of protein depolymerization, N mineralization and nitrification (determined using 15N pool dilution assays) in organic topsoil, mineral topsoil, and mineral subsoil of seven ecosystems along a latitudinal transect in western Siberia, from tundra (67°N) to steppe (54°N). The investigated ecosystems differed strongly in N transformation rates, with highest protein depolymerization and N mineralization rates in middle and southern taiga. All N transformation rates decreased with soil depth following the decrease in organic matter content. Related to protein depolymerization, N mineralization and nitrification were significantly higher in mineral than in organic horizons, supporting a decrease in microbial N limitation with depth. In contrast, we did not find indications for a decrease in microbial N limitation from arctic to temperate ecosystems along the transect. Our findings thus challenge the perception of ubiquitous N limitation at high latitudes, but suggest a transition from N to C limitation of microorganisms with soil depth, even in high-latitude systems such as tundra and boreal forest.
ASJC Scopus Sachgebiete
- Umweltwissenschaften (insg.)
- Globaler Wandel
- Umweltwissenschaften (insg.)
- Umweltchemie
- Umweltwissenschaften (insg.)
- Erdkunde und Planetologie (insg.)
- Atmosphärenwissenschaften
Zitieren
- Standard
- Harvard
- Apa
- Vancouver
- BibTex
- RIS
in: Global biogeochemical cycles, Jahrgang 29, Nr. 5, 01.05.2015, S. 567-582.
Publikation: Beitrag in Fachzeitschrift › Artikel › Forschung › Peer-Review
}
TY - JOUR
T1 - Microbial nitrogen dynamics in organic and mineral soil horizons along a latitudinal transect in western Siberia
AU - Wild, Birgit
AU - Schnecker, Jörg
AU - Knoltsch, Anna
AU - Takriti, Mounir
AU - Mooshammer, Maria
AU - Gentsch, Norman
AU - Mikutta, Robert
AU - Alves, Ricardo J.Eloy
AU - Gittel, Antje
AU - Lashchinskiy, Nikolay
AU - Richter, Andreas
N1 - Publisher Copyright: ©2015. The Authors. Copyright: Copyright 2018 Elsevier B.V., All rights reserved.
PY - 2015/5/1
Y1 - 2015/5/1
N2 - Soil N availability is constrained by the breakdown of N-containing polymers such as proteins to oligopeptides and amino acids that can be taken up by plants and microorganisms. Excess N is released from microbial cells as ammonium (N mineralization), which in turn can serve as substrate for nitrification. According to stoichiometric theory, N mineralization and nitrification are expected to increase in relation to protein depolymerization with decreasing N limitation, and thus from higher to lower latitudes and from topsoils to subsoils. To test these hypotheses, we compared gross rates of protein depolymerization, N mineralization and nitrification (determined using 15N pool dilution assays) in organic topsoil, mineral topsoil, and mineral subsoil of seven ecosystems along a latitudinal transect in western Siberia, from tundra (67°N) to steppe (54°N). The investigated ecosystems differed strongly in N transformation rates, with highest protein depolymerization and N mineralization rates in middle and southern taiga. All N transformation rates decreased with soil depth following the decrease in organic matter content. Related to protein depolymerization, N mineralization and nitrification were significantly higher in mineral than in organic horizons, supporting a decrease in microbial N limitation with depth. In contrast, we did not find indications for a decrease in microbial N limitation from arctic to temperate ecosystems along the transect. Our findings thus challenge the perception of ubiquitous N limitation at high latitudes, but suggest a transition from N to C limitation of microorganisms with soil depth, even in high-latitude systems such as tundra and boreal forest.
AB - Soil N availability is constrained by the breakdown of N-containing polymers such as proteins to oligopeptides and amino acids that can be taken up by plants and microorganisms. Excess N is released from microbial cells as ammonium (N mineralization), which in turn can serve as substrate for nitrification. According to stoichiometric theory, N mineralization and nitrification are expected to increase in relation to protein depolymerization with decreasing N limitation, and thus from higher to lower latitudes and from topsoils to subsoils. To test these hypotheses, we compared gross rates of protein depolymerization, N mineralization and nitrification (determined using 15N pool dilution assays) in organic topsoil, mineral topsoil, and mineral subsoil of seven ecosystems along a latitudinal transect in western Siberia, from tundra (67°N) to steppe (54°N). The investigated ecosystems differed strongly in N transformation rates, with highest protein depolymerization and N mineralization rates in middle and southern taiga. All N transformation rates decreased with soil depth following the decrease in organic matter content. Related to protein depolymerization, N mineralization and nitrification were significantly higher in mineral than in organic horizons, supporting a decrease in microbial N limitation with depth. In contrast, we did not find indications for a decrease in microbial N limitation from arctic to temperate ecosystems along the transect. Our findings thus challenge the perception of ubiquitous N limitation at high latitudes, but suggest a transition from N to C limitation of microorganisms with soil depth, even in high-latitude systems such as tundra and boreal forest.
KW - boreal forest
KW - permafrost
KW - protein depolymerization
KW - tundra
UR - http://www.scopus.com/inward/record.url?scp=85027955958&partnerID=8YFLogxK
U2 - 10.1002/2015GB005084
DO - 10.1002/2015GB005084
M3 - Article
AN - SCOPUS:85027955958
VL - 29
SP - 567
EP - 582
JO - Global biogeochemical cycles
JF - Global biogeochemical cycles
SN - 0886-6236
IS - 5
ER -