TY - JOUR
T1 - Spatial heterogeneity and soil nitrogen dynamics in a burned black spruce forest stand
T2 - Distinct controls at different scales
AU - Smithwick, Erica A.H.
AU - Mack, Michelle C.
AU - Turner, Monica G.
AU - Chapin, F. Stuart
AU - Zhu, Jun
AU - Balser, Teri C.
PY - 2005/12/1
Y1 - 2005/12/1
N2 - We evaluated spatial patterns of soil N and C mineralization, microbial community composition (phospholipid fatty acids), and local site characteristics (plant/forest floor cover, soil pH, soil %C and %N) in a 0.25-ha burned black spruce forest stand in interior Alaska. Results indicated that factors governing soil N and C mineralization varied at two different scales. In situ net N mineralization was autocorrelated with microbial community composition at relatively broad scales (∼8 m) and with local site characteristics ('site' axis 1 of non-metric scaling ordination) at relatively fine scales (2-4 m). At the scale of the individual core, soil moisture was the best predictor of in situ net N mineralization and laboratory C mineralization, explaining between 47 and 67% of the variation (p < 0.001). Ordination of microbial lipid data showed that bacteria were more common in severely burned microsites, whereas fungi were more common in low fire severity microsites. We conclude that C and N mineralization rates in this burned black spruce stand were related to different variables depending on the scale of analysis, suggesting the importance of considering multiple scales of variability among key drivers of C and N transformations.
AB - We evaluated spatial patterns of soil N and C mineralization, microbial community composition (phospholipid fatty acids), and local site characteristics (plant/forest floor cover, soil pH, soil %C and %N) in a 0.25-ha burned black spruce forest stand in interior Alaska. Results indicated that factors governing soil N and C mineralization varied at two different scales. In situ net N mineralization was autocorrelated with microbial community composition at relatively broad scales (∼8 m) and with local site characteristics ('site' axis 1 of non-metric scaling ordination) at relatively fine scales (2-4 m). At the scale of the individual core, soil moisture was the best predictor of in situ net N mineralization and laboratory C mineralization, explaining between 47 and 67% of the variation (p < 0.001). Ordination of microbial lipid data showed that bacteria were more common in severely burned microsites, whereas fungi were more common in low fire severity microsites. We conclude that C and N mineralization rates in this burned black spruce stand were related to different variables depending on the scale of analysis, suggesting the importance of considering multiple scales of variability among key drivers of C and N transformations.
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U2 - 10.1007/s10533-005-0031-y
DO - 10.1007/s10533-005-0031-y
M3 - Article
AN - SCOPUS:28444442732
VL - 76
SP - 517
EP - 537
JO - Biogeochemistry
JF - Biogeochemistry
SN - 0168-2563
IS - 3
ER -