 |
| Titel |
Carbon allocation and carbon isotope fluxes in the plant-soil-atmosphere continuum: a review |
| VerfasserIn |
N. Brüggemann, A. Gessler, Z. Kayler, S. G. Keel, F. Badeck, M. Barthel, P. Boeckx, N. Buchmann, E. Brugnoli, J. Esperschütz, O. Gavrichkova, J. Ghashghaie, N. Gomez-Casanovas, C. Keitel, A. Knohl, D. Kuptz, S. Palacio, Y. Salmon, Y. Uchida, M. Bahn |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1726-4170
|
| Digitales Dokument |
URL |
| Erschienen |
In: Biogeosciences ; 8, no. 11 ; Nr. 8, no. 11 (2011-11-28), S.3457-3489 |
| Datensatznummer |
250006211
|
| Publikation (Nr.) |
 copernicus.org/bg-8-3457-2011.pdf |
|
|
|
|
|
| Zusammenfassung |
| The terrestrial carbon (C) cycle has received increasing interest over the
past few decades, however, there is still a lack of understanding of the
fate of newly assimilated C allocated within plants and to the soil, stored
within ecosystems and lost to the atmosphere. Stable carbon isotope studies
can give novel insights into these issues. In this review we provide an
overview of an emerging picture of plant-soil-atmosphere C fluxes, as based
on C isotope studies, and identify processes determining related C isotope
signatures. The first part of the review focuses on isotopic fractionation
processes within plants during and after photosynthesis. The second major
part elaborates on plant-internal and plant-rhizosphere C allocation
patterns at different time scales (diel, seasonal, interannual), including
the speed of C transfer and time lags in the coupling of assimilation and
respiration, as well as the magnitude and controls of plant-soil C
allocation and respiratory fluxes. Plant responses to changing environmental
conditions, the functional relationship between the physiological and
phenological status of plants and C transfer, and interactions between C,
water and nutrient dynamics are discussed. The role of the C counterflow
from the rhizosphere to the aboveground parts of the plants, e.g. via
CO2 dissolved in the xylem water or as xylem-transported sugars, is
highlighted. The third part is centered around belowground C turnover,
focusing especially on above- and belowground litter inputs, soil organic
matter formation and turnover, production and loss of dissolved organic C,
soil respiration and CO2 fixation by soil microbes. Furthermore, plant
controls on microbial communities and activity via exudates and litter
production as well as microbial community effects on C mineralization are
reviewed. A further part of the paper is dedicated to physical interactions
between soil CO2 and the soil matrix, such as CO2 diffusion and
dissolution processes within the soil profile. Finally, we highlight
state-of-the-art stable isotope methodologies and their latest developments.
From the presented evidence we conclude that there exists a tight coupling
of physical, chemical and biological processes involved in C cycling and C
isotope fluxes in the plant-soil-atmosphere system. Generally, research
using information from C isotopes allows an integrated view of the different
processes involved. However, complex interactions among the range of
processes complicate or currently impede the interpretation of isotopic
signals in CO2 or organic compounds at the plant and ecosystem level.
This review tries to identify present knowledge gaps in correctly interpreting carbon
stable isotope signals in the plant-soil-atmosphere system and
how future research approaches could contribute to closing these gaps. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|