The effect of canopy structure on soil respiration in an old‐growth beech‐oak forest in central Japan. Issue 5 (18th June 2015)

• Record Type: Journal Article
• Authors: Suchewaboripont, Vilanee; Ando, Masaki; Iimura, Yasuo; Yoshitake, Shinpei; Ohtsuka, Toshiyuki
• Is Part Of: Ecological research. Volume 30:Issue 5(2015)
• Page Start: 867
• Page End: 877
• Publication Date: 2015-06-18
• Subjects: Soil respiration -- Spatial variation -- Gap/canopy structure -- Fine root -- Old‐growth forest; Ecology -- Periodicals; Ecology -- Japan -- Periodicals; Écologie; Japon; Ecology; Japan; Ressource Internet (Descripteur de forme); Périodique électronique (Descripteur de forme); Periodicals; 577.05
• DOI: 10.1007/s11284-015-1286-y
• Languages: English
• ISSNs: 0912-3814

Abstract

Abstract: Soil respiration ( R s ) is a key component in the estimation of the net ecosystem production (NEP) of old‐growth forests, which are generally thought to have ceased carbon accumulation. The objectives of the present study were to characterize the spatial and temporal patterns of R s, and to identify the determinants of the spatial and temporal variability of R s, using general linear mixed models (GLMM), in an old‐growth beech‐oak forest. GLMM analyses identified monthly effect as a significant explanatory variable for temporal variation, as well as gap/canopy and soil water content ( SWC ) as explanatory variables for spatial variation, in R s . The complexity of vertical structure in the forest was reflected in the spatial pattern of R s, which was higher in canopy areas than in gap areas during the growing season, except in November. This spatial pattern was not affected by soil temperature. Moreover, SWC did not differ between gap and canopy areas, although SWC partially explained the spatial heterogeneity in R s . The carbon:nitrogen ratios of soil organic matter in canopy areas were significantly higher than those in gap areas. Fine root biomass was 1.7‐fold greater in canopy areas than in gap areas, likely because of the higher R s in canopy areas, and root respiration made a much large contribution to R s than heterotrophic respiration. The different patterns of fine root biomass between gap and canopy areas mainly control the spatial heterogeneity in R s ; thus, it is worth considering the gap/canopy variability in R s when evaluating annual efflux in old‐growth forests.