TY  - JOUR
A1  - Scherber, Christoph
A1  - Eisenhauer, Nico
A1  - Weisser, Wolfgang W.
A1  - Schmid, Bernhard
A1  - Voigt, Winfried
A1  - Fischer, Markus
A1  - Schukze, Ernst-Detlef
A1  - Roscher, Christiane
A1  - Weigelt, Alexandra
A1  - Allan, Eric
A1  - Beßler, Holger
A1  - Bonkowski, Michael
A1  - Buchmann, Nina
A1  - Buscot, François
A1  - Clement, Lars W.
A1  - Ebeling, Anne
A1  - Engels, Christof
A1  - Halle, Stefan
A1  - Kertscher, Ilona
A1  - Klein, Alexandra-Maria
A1  - Koller, Robert
A1  - König, Stephan
A1  - Kowalski, Esther
A1  - Kummer, Volker
A1  - Kuu, Annely
A1  - Lange, Markus
A1  - Lauterbach, Dirk
T1  - Bottom-up effects of plant diversity on multitrophic interactions in a biodiversity experiment
Y1  - 2010
UR  - http://www.nature.com/nature/journal/v468/n7323/full/nature09492.html
SN  - 0028-0836
ER  - 
TY  - JOUR
A1  - Hoffmann, Mathias
A1  - Wirth, Stephan J.
A1  - Bessler, Holger
A1  - Engels, Christof
A1  - Jochheim, Hubert
A1  - Sommer, Michael
A1  - Augustin, Jürgen
T1  - Combining a root exclusion technique with continuous chamber and porous tube measurements for a pin-point separation of ecosystem respiration in croplands
JF  - Journal of plant nutrition and soil science = Zeitschrift für Pflanzenernährung und Bodenkunde
N2  - To better assess ecosystem C budgets of croplands and understand their potential response to climate and management changes, detailed information on the mechanisms and environmental controls driving the individual C flux components are needed. This accounts in particular for the ecosystem respiration (R-eco) and its components, the autotrophic (R-a) and heterotrophic respiration (R-h) which vary tremendously in time and space. This study presents a method to separate R-eco into R-a [as the sum of R-a (shoot) and R-a (root)] and R-h in order to detect temporal and small-scale spatial dynamics within their relative contribution to overall R-eco. Thus, predominant environmental drivers and underlying mechanisms can be revealed. R-eco was derived during nighttime by automatic chamber CO2 flux measurements on plant covered plots. R-h was derived from CO2 efflux measurements, which were performed in parallel to R-eco measurements on a fallow plot using CO2 sampling tubes in 10 cm soil depth. R-a (root) was calculated as the difference between sampling tube CO2 efflux measurements on a plant covered plot and R-h. R-a (shoot) was calculated as R-eco - R-a (root) - R-h. Measurements were carried out for winter wheat (Triticum aestivum L.) during the crop season 2015 at an experimental plot located in the hummocky ground moraine landscape of NE Germany. R-eco varied seasonally from < 1 to 9.5 g C m(-2) d(-1), and was higher in adult (a) and reproductive (r) than juvenile (j) stands (gC m(-2) d(-1): j = 1.2, a = 4.6, r = 5.3). Observed R-a and R-h were in general smaller compared to the independently measured R-eco, contributing in average 58% and 42% to R-eco. However, both varied strongly regarding their environmental drivers and particular contribution throughout the study period, following the seasonal development of soil temperature and moisture (R-h) as well as crop development (R-a). Thus, our results consistently revealed temporal dynamics regarding the relative contribution of R-a (root) and R-a (shoot) to R-a, as well as of R-a and R-h to R-eco. Based on the observed results, implications for partitioning of R-eco in croplands are given.
KW  - automatic chambers
KW  - autotrophic respiration
KW  - heterotrophic respiration
KW  - soil CO2 sampling tubes
Y1  - 2017
U6  - https://doi.org/10.1002/jpln.201600489
SN  - 1436-8730
SN  - 1522-2624
VL  - 181
IS  - 1
SP  - 41
EP  - 50
PB  - Wiley-VCH
CY  - Weinheim
ER  -