55210
2017
2017
eng
1003
1019
17
4
14
article
Copernicus
Göttingen
1
2017-03-03
2017-03-03
--
Detecting small-scale spatial heterogeneity and temporal dynamics of soil organic carbon (SOC) stocks
Carbon (C) sequestration in soils plays a key role in the global C cycle. It is therefore crucial to adequately monitor dynamics in soil organic carbon (Delta SOC) stocks when aiming to reveal underlying processes and potential drivers. However, small-scale spatial (10-30 m) and temporal changes in SOC stocks, particularly pronounced in arable lands, are hard to assess. The main reasons for this are limitations of the well-established methods. On the one hand, repeated soil inventories, often used in long-term field trials, reveal spatial patterns and trends in Delta SOC but require a longer observation period and a sufficient number of repetitions. On the other hand, eddy covariance measurements of C fluxes towards a complete C budget of the soil-plant-atmosphere system may help to obtain temporal Delta SOC patterns but lack small-scale spatial resolution. To overcome these limitations, this study presents a reliable method to detect both short-term temporal dynamics as well as small-scale spatial differences of Delta SOC using measurements of the net ecosystem carbon balance (NECB) as a proxy. To estimate the NECB, a combination of automatic chamber (AC) measurements of CO2 exchange and empirically modeled aboveground biomass development (NPPshoot / were used. To verify our method, results were compared with Delta SOC observed by soil resampling. Soil resampling and AC measurements were performed from 2010 to 2014 at a colluvial depression located in the hummocky ground moraine landscape of northeastern Germany. The measurement site is characterized by a variable groundwater level (GWL) and pronounced small-scale spatial heterogeneity regarding SOC and nitrogen (Nt) stocks. Tendencies and magnitude of Delta SOC values derived by AC measurements and repeated soil inventories corresponded well. The period of maximum plant growth was identified as being most important for the development of spatial differences in annual Delta SOC. Hence, we were able to confirm that AC-based C budgets are able to reveal small-scale spatial differences and short-term temporal dynamics of Delta SOC.
Biogeosciences
a comparison between automatic chamber-derived C budgets and repeated soil inventories
10.5194/bg-14-1003-2017
1726-4170
1726-4189
wos:2017
WOS:000395322400002
Hoffmann, M (reprint author), Leibniz Ctr Agr Landscape Res ZALF, Inst Soil Landscape Res, Eberswalder Str 84, D-15374 Muncheberg, Germany., mathias.hoffmann@zalf.de
2022-06-17T07:28:14+00:00
sword
importub
filename=package.tar
63ba29c4323c8be38bcebdfe7b713015
false
true
Mathias Hoffmann
Nicole Jurisch
Juana Garcia Alba
Elisa Albiac Borraz
Marten Schmidt
Vytas Huth
Helmut Rogasik
Helene Rieckh
Gernot Verch
Michael Sommer
Jürgen Augustin
Geowissenschaften
Institut für Geowissenschaften
Referiert
Import
55531
2017
2017
eng
109
118
10
1
10
article
Copernicus
Göttingen
1
2017-01-06
2017-01-06
--
A simple calculation algorithm to separate high-resolution CH4 flux measurements into ebullition- and diffusion-derived components
Processes driving the production, transformation and transport of methane (CH4 / in wetland ecosystems are highly complex. We present a simple calculation algorithm to separate open-water CH4 fluxes measured with automatic chambers into diffusion-and ebullition-derived components. This helps to reveal underlying dynamics, to identify potential environmental drivers and, thus, to calculate reliable CH4 emission estimates. The flux separation is based on identification of ebullition-related sudden concentration changes during single measurements. Therefore, a variable ebullition filter is applied, using the lower and upper quartile and the interquartile range (IQR). Automation of data processing is achieved by using an established R script, adjusted for the purpose of CH4 flux calculation. The algorithm was validated by performing a laboratory experiment and tested using flux measurement data (July to September 2013) from a former fen grassland site, which converted into a shallow lake as a result of rewetting. Ebullition and diffusion contributed equally (46 and 55 %) to total CH4 emissions, which is comparable to ratios given in the literature. Moreover, the separation algorithm revealed a concealed shift in the diurnal trend of diffusive fluxes throughout the measurement period. The water temperature gradient was identified as one of the major drivers of diffusive CH4 emissions, whereas no significant driver was found in the case of erratic CH4 ebullition events.
Atmospheric measurement techniques : an interactive open access journal of the European Geosciences Union
10.5194/amt-10-109-2017
1867-1381
1867-8548
wos:2017
WOS:000391281800002
Hoffmann, M (reprint author), Leibniz Ctr Agr Landscape Res ZALF eV, Inst Soil Landscape Res, Eberswalder Str 84, D-15374 Muncheberg, Germany., mathias.hoffmann@zalf.de
2022-07-08T12:06:01+00:00
sword
importub
filename=package.tar
9b328647b24bfed1463cf31e69731615
false
true
Mathias Hoffmann
Maximilian Schulz-Hanke
Juana Garcia Alba
Nicole Jurisch
Ulrike Hagemann
Torsten Sachs
Michael Sommer
Jürgen Augustin
Geowissenschaften
Institut für Geowissenschaften
Referiert
Import
41665
2017
2017
eng
109
118
10
604
postprint
1
2019-02-14
2019-02-14
--
A simple calculation algorithm to separate high-resolution CH4 flux measurements into ebullition- and diffusion-derived components
Processes driving the production, transformation and transport of methane (CH4) in wetland ecosystems are highly complex. We present a simple calculation algorithm to separate open-water CH4 fluxes measured with automatic chambers into diffusion- and ebullition-derived components. This helps to reveal underlying dynamics, to identify potential environmental drivers and, thus, to calculate reliable CH4 emission estimates. The flux separation is based on identification of ebullition-related sudden concentration changes during single measurements. Therefore, a variable ebullition filter is applied, using the lower and upper quartile and the interquartile range (IQR). Automation of data processing is achieved by using an established R script, adjusted for the purpose of CH4 flux calculation. The algorithm was validated by performing a laboratory experiment and tested using flux measurement data (July to September 2013) from a former fen grassland site, which converted into a shallow lake as a result of rewetting. Ebullition and diffusion contributed equally (46 and 55 %) to total CH4 emissions, which is comparable to ratios given in the literature. Moreover, the separation algorithm revealed a concealed shift in the diurnal trend of diffusive fluxes throughout the measurement period. The water temperature gradient was identified as one of the major drivers of diffusive CH4 emissions, whereas no significant driver was found in the case of erratic CH4 ebullition events.
Postprints der Universität Potsdam : Mathematisch Naturwissenschaftliche Reihe
10.25932/publishup-41665
urn:nbn:de:kobv:517-opus4-416659
1866-8372
online registration
Atmospheric Measurement Techniques 10 (2017) 1, pp. 109–118 DOI 10.5194/amt-10-109-2017
<a href="http://publishup.uni-potsdam.de/55531">Bibliographieeintrag der Originalveröffentlichung/Quelle</a>
CC-BY - Namensnennung 4.0 International
Mathias Hoffmann
Maximilian Schulz-Hanke
Juana Garcia Alba
Nicole Jurisch
Ulrike Hagemann
Torsten Sachs
Michael Sommer
Jürgen Augustin
Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
604
eng
uncontrolled
water methane emissions
eng
uncontrolled
chamber system
eng
uncontrolled
CO2
eng
uncontrolled
lake
eng
uncontrolled
fen
eng
uncontrolled
exchange
eng
uncontrolled
mechanism
eng
uncontrolled
turbulence
eng
uncontrolled
transport
eng
uncontrolled
reservior
Geowissenschaften
open_access
Mathematisch-Naturwissenschaftliche Fakultät
Referiert
Open Access
Universität Potsdam
https://publishup.uni-potsdam.de/files/41665/pmnr604.pdf
41711
2017
2019
eng
17
666
postprint
1
2019-03-04
2019-03-04
--
Detecting small-scale spatial heterogeneity and temporal dynamics of soil organic carbon (SOC) stocks
Carbon (C) sequestration in soils plays a key role in the global C cycle. It is therefore crucial to adequately monitor dynamics in soil organic carbon (Delta SOC) stocks when aiming to reveal underlying processes and potential drivers. However, small-scale spatial (10-30 m) and temporal changes in SOC stocks, particularly pronounced in arable lands, are hard to assess. The main reasons for this are limitations of the well-established methods. On the one hand, repeated soil inventories, often used in long-term field trials, reveal spatial patterns and trends in Delta SOC but require a longer observation period and a sufficient number of repetitions. On the other hand, eddy covariance measurements of C fluxes towards a complete C budget of the soil-plant-atmosphere system may help to obtain temporal Delta SOC patterns but lack small-scale spatial resolution.
To overcome these limitations, this study presents a reliable method to detect both short-term temporal dynamics as well as small-scale spatial differences of Delta SOC using measurements of the net ecosystem carbon balance (NECB) as a proxy. To estimate the NECB, a combination of automatic chamber (AC) measurements of CO2 exchange and empirically modeled aboveground biomass development (NPPshoot / were used. To verify our method, results were compared with Delta SOC observed by soil resampling.
Soil resampling and AC measurements were performed from 2010 to 2014 at a colluvial depression located in the hummocky ground moraine landscape of northeastern Germany. The measurement site is characterized by a variable groundwater level (GWL) and pronounced small-scale spatial heterogeneity regarding SOC and nitrogen (Nt) stocks. Tendencies and magnitude of Delta SOC values derived by AC measurements and repeated soil inventories corresponded well. The period of maximum plant growth was identified as being most important for the development of spatial differences in annual Delta SOC. Hence, we were able to confirm that AC-based C budgets are able to reveal small-scale spatial differences and short-term temporal dynamics of Delta SOC.
Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
a comparison between automatic chamber-derived C budgets and repeated soil inventories
10.25932/publishup-41711
urn:nbn:de:kobv:517-opus4-417118
1866-8372
online registration
Biogeosciences 14 (2017), pp. 1003–1019 DOI 10.5194/bg-14-1003-2017
false
true
CC-BY - Namensnennung 4.0 International
Mathias Hoffmann
Nicole Jurisch
Juana Garcia Alba
Elisa Albiac Borraz
Marten Schmidt
Vytas Huth
Helmut Rogasik
Helene Rieckh
Gernot Verch
Michael Sommer
Jürgen Augustin
Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
666
eng
uncontrolled
net ecosystem exchange
eng
uncontrolled
North Central region
eng
uncontrolled
no-till ecosystem
eng
uncontrolled
eddy covariance
eng
uncontrolled
CO2 fluxes
eng
uncontrolled
dioxide exchange
eng
uncontrolled
United States
eng
uncontrolled
gas-exchange
eng
uncontrolled
agricultural landscapes
eng
uncontrolled
monitoring networks
Geowissenschaften
Biowissenschaften; Biologie
open_access
Mathematisch-Naturwissenschaftliche Fakultät
Referiert
Open Access
Universität Potsdam
https://publishup.uni-potsdam.de/files/41711/pmnr666.pdf