DOI: 10.1111/gcb.12161
论文题名: Enhanced root exudation stimulates soil nitrogen transformations in a subalpine coniferous forest under experimental warming
作者: Yin H. ; Li Y. ; Xiao J. ; Xu Z. ; Cheng X. ; Liu Q.
刊名: Global Change Biology
ISSN: 13541013
出版年: 2013
卷: 19, 期: 7 起始页码: 2158
结束页码: 2167
语种: 英语
英文关键词: Exudation
; N transformation
; Nutrient availability
; Subalpine coniferous forest
; Warming
Scopus关键词: biomass
; coniferous forest
; enzyme
; microbial activity
; morphology
; nitrogen cycle
; nutrient availability
; physiology
; root
; soil fertility
; soil nitrogen
; soil temperature
; subalpine environment
; temperature effect
; warming
; article
; biomass
; chemistry
; China
; greenhouse effect
; growth, development and aging
; nitrogen cycle
; plant exudate
; plant root
; soil
; spruce
; theoretical model
; Biomass
; China
; Global Warming
; Models, Theoretical
; Nitrogen Cycle
; Picea
; Plant Exudates
; Plant Roots
; Soil
; Picea
; Picea asperata
英文摘要: Despite the perceived importance of exudation to forest ecosystem function, few studies have attempted to examine the effects of elevated temperature and nutrition availability on the rates of root exudation and associated microbial processes. In this study, we performed an experiment in which in situ exudates were collected from Picea asperata seedlings that were transplanted in disturbed soils exposed to two levels of temperature (ambient temperature and infrared heater warming) and two nitrogen levels (unfertilized and 25 g N m-2 a-1). Here, we show that the trees exposed to an elevated temperature increased their exudation rates I (μg C g-1 root biomass h-1), II (μg C cm-1 root length h-1) and III (μg C cm-2 root area h-1) in the unfertilized plots. The altered morphological and physiological traits of the roots exposed to experimental warming could be responsible for this variation in root exudation. Moreover, these increases in root-derived C were positively correlated with the microbial release of extracellular enzymes involved in the breakdown of organic N (R2 = 0.790; P = 0.038), which was coupled with stimulated microbial activity and accelerated N transformations in the unfertilized soils. In contrast, the trees exposed to both experimental warming and N fertilization did not show increased exudation rates or soil enzyme activity, indicating that the stimulatory effects of experimental warming on root exudation depend on soil fertility. Collectively, our results provide preliminary evidence that an increase in the release of root exudates into the soil may be an important physiological adjustment by which the sustained growth responses of plants to experimental warming may be maintained via enhanced soil microbial activity and soil N transformation. Accordingly, the underlying mechanisms by which plant root-microbe interactions influence soil organic matter decomposition and N cycling should be incorporated into climate-carbon cycle models to determine reliable estimates of long-term C storage in forests. © 2013 Blackwell Publishing Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/62413
Appears in Collections: 影响、适应和脆弱性
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作者单位: Chengdu Institute of Biology, Chinese Academy of Sciences, P. O. Box 416, Chengdu, 610041, China; Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization, Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province, Chinese Academy of Sciences, Chengdu, 610041, China; Institute of Ecology and Forestry, Sichuan Agricultural University, Chengdu, 611130, China
Recommended Citation:
Yin H.,Li Y.,Xiao J.,et al. Enhanced root exudation stimulates soil nitrogen transformations in a subalpine coniferous forest under experimental warming[J]. Global Change Biology,2013-01-01,19(7)