scholarly journals Improvement of Soil Respiration Parameterization in a Dynamic Global Vegetation Model and Its Impact on the Simulation of Terrestrial Carbon Fluxes

2018 ◽  
Vol 32 (1) ◽  
pp. 127-143 ◽  
Author(s):  
Dongmin Kim ◽  
Myong-In Lee ◽  
Eunkyo Seo
Keyword(s):  
Spatial Distribution ◽  
Soil Respiration ◽  
Soil Temperature ◽  
Vegetation Type ◽  
Carbon Fluxes ◽  
Decomposition Process ◽  
Spatial And Temporal Variation ◽  
In Situ Observation ◽  
Terrestrial Carbon ◽  
Soil Temperature And Moisture

Abstract The Q10 value represents the soil respiration sensitivity to temperature often used for the parameterization of the soil decomposition process has been assumed to be a constant in conventional numerical models, whereas it exhibits significant spatial and temporal variation in the observations. This study develops a new parameterization method for determining Q10 by considering the soil respiration dependence on soil temperature and moisture obtained by multiple regression for each vegetation type. This study further investigates the impacts of the new parameterization on the global terrestrial carbon flux. Our results show that a nonuniform spatial distribution of Q10 tends to better represent the dependence of the soil respiration process on heterogeneous surface vegetation type compared with the control simulation using a uniform Q10. Moreover, it tends to improve the simulation of the relationship between soil respiration and soil temperature and moisture, particularly over cold and dry regions. The modification has an impact on the soil respiration and carbon decomposition process, which changes gross primary production (GPP) through controlling nutrient assimilation from soil to vegetation. It leads to a realistic spatial distribution of GPP, particularly over high latitudes where the original model has a significant underestimation bias. Improvement in the spatial distribution of GPP leads to a substantial reduction of global mean GPP bias compared with the in situ observation-based reference data. The results highlight that the enhanced sensitivity of soil respiration to the subsurface soil temperature and moisture introduced by the nonuniform spatial distribution of Q10 has contributed to improving the simulation of the terrestrial carbon fluxes and the global carbon cycle.

scholarly journals Improvement of Soil Respiration Parameterization in a Dynamic Global Vegetation Model and Its Impact on the Simulation of Terrestrial Carbon Fluxes

2017 ◽  
Author(s):  
Dongmin Kim ◽  
Myong-In Lee ◽  
Eunkyo Seo
Keyword(s):  
Spatial Distribution ◽  
Soil Respiration ◽  
Soil Temperature ◽  
Numerical Models ◽  
Gross Primary Production ◽  
Substantial Reduction ◽  
Observation Data ◽  
Terrestrial Carbon ◽  
Dynamic Global Vegetation Model ◽  
Soil Temperature And Moisture

Abstract. Soil decomposition is one of the critical processes for maintaining a terrestrial ecosystem and the global carbon cycle. The sensitivity of soil respiration (Rs) to temperature, the so-called Q10 value, is required for parameterizing the soil decomposition process and is assumed to be a constant in conventional numerical models, while realistically it is not in cases of spatiotemporal heterogeneity. This study develops a new parameterization method for determining Q10 by considering the soil respiration dependence on soil temperature and moisture obtained by multiple regression. This study further investigates the impacts of the new parameterization on the global terrestrial carbon flux. Our results show that non-uniform spatial distribution of Q10 tends to represent the dependence of the soil respiration process on heterogeneous surface vegetation type compared with the control simulation using a uniform Q10. Moreover, it tends to improve the simulation of the observed relationship between soil respiration and soil temperature and moisture, particularly over cold and dry regions. The new parameterization improves the simulation of gross primary production (GPP). It leads to a more realistic spatial distribution of GPP, particularly over high latitudes (60–80 N) where the original model has a significant underestimation bias. In addition, overestimation bias of GPP in the tropics and the midlatitudes is significantly reduced. Improvement in the spatial distribution of GPP leads to a substantial reduction of global mean bias of GPP from +9.11 to +1.68 GtC yr−1 compared with the FLUXNET-MTE observation data.

Interpreting the dependence of soil respiration on soil temperature and moisture in an oasis cotton field, central Asia

2013 ◽  
Vol 168 ◽  
pp. 46-52 ◽  
Author(s):  
Zhi Min Zhao ◽  
Cheng Yi Zhao ◽  
Ying Yu Yan ◽  
Ju Yan Li ◽  
Jun Li ◽  
...  
Keyword(s):  
Soil Respiration ◽  
Soil Temperature ◽  
Central Asia ◽  
Cotton Field ◽  
Soil Temperature And Moisture

scholarly journals Effects of Soil Temperature and Moisture on Soil Respiration on the Tibetan Plateau

PLoS ONE ◽  
2016 ◽  
Vol 11 (10) ◽  
pp. e0165212 ◽  
Author(s):  
Xiaoying Bao ◽  
Xiaoxue Zhu ◽  
Xiaofeng Chang ◽  
Shiping Wang ◽  
Burenbayin Xu ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
Soil Respiration ◽  
Soil Temperature ◽  
The Tibetan Plateau ◽  
Soil Temperature And Moisture

scholarly journals Spatial and temporal variation of CO<sub>2</sub> efflux along a disturbance gradient in a <i>miombo</i> woodland in Western Zambia

2011 ◽  
Vol 8 (1) ◽  
pp. 147-164 ◽  
Author(s):  
L. Merbold ◽  
W. Ziegler ◽  
M. M. Mukelabai ◽  
W. L. Kutsch
Keyword(s):  
Soil Respiration ◽  
Soil Temperature ◽  
Temporal Variation ◽  
Carbon Content ◽  
Ecosystem Respiration ◽  
Spatial And Temporal Variation ◽  
Co2 Efflux ◽  
Forest Reserve ◽  
Disturbance Gradient ◽  
Total Ecosystem Respiration

Abstract. Carbon dioxide efflux from the soil surface was measured over a period of several weeks within a heterogeneous Brachystegia spp. dominated miombo woodland in Western Zambia. The objectives were to examine spatial and temporal variation of soil respiration along a disturbance gradient from a protected forest reserve to a cut, burned, and grazed area outside, and to relate the flux to various abiotic and biotic drivers. The highest daily mean fluxes (around 12 μmol CO2 m−2 s−1) were measured in the protected forest in the wet season and lowest daily mean fluxes (around 1 μmol CO2 m−2 s−1) in the most disturbed area during the dry season. Diurnal variation of soil respiration was closely correlated with soil temperature. The combination of soil water content and soil temperature was found to be the main driving factor at seasonal time scale. There was a 75% decrease in soil CO2 efflux during the dry season and a 20% difference in peak soil respiratory flux measured in 2008 and 2009. Spatial variation of CO2 efflux was positively related to total soil carbon content in the undisturbed area but not at the disturbed site. Coefficients of variation of efflux rates between plots decreased towards the core zone of the protected forest reserve. Normalized soil respiration values did not vary significantly along the disturbance gradient. Spatial variation of respiration did not show a clear distinction between the disturbed and undisturbed sites and could not be explained by variables such as leaf area index. In contrast, within plot variability of soil respiration was explained by soil organic carbon content. Three different approaches to calculate total ecosystem respiration (Reco) from eddy covariance measurements were compared to two bottom-up estimates of Reco obtained from chambers measurements of soil- and leaf respiration which differed in the consideration of spatial heterogeneity. The consideration of spatial variability resulted only in small changes of Reco when compared to simple averaging. Total ecosystem respiration at the plot scale, obtained by eddy covariance differed by up to 25% in relation to values calculated from the soil- and leaf chamber efflux measurements but without showing a clear trend.

Significance of soil temperature and moisture for soil respiration in a Chinese mountain area

2008 ◽  
Vol 148 (3) ◽  
pp. 490-503 ◽  
Author(s):  
Hong-jian Li ◽  
Jun-xia Yan ◽  
Xiao-feng Yue ◽  
Meng-ben Wang
Keyword(s):  
Soil Respiration ◽  
Soil Temperature ◽  
Mountain Area ◽  
Soil Temperature And Moisture

Climate factors mediate soil respiration dynamics in Mediterranean agricultural environments: an empirical approach

Soil Research ◽  
2014 ◽  
Vol 52 (6) ◽  
pp. 543 ◽  
Author(s):  
Sergio González-Ubierna ◽  
María Teresa de la Cruz ◽  
Miguel Ángel Casermeiro
Keyword(s):  
Soil Respiration ◽  
Soil Temperature ◽  
Coefficient Of Determination ◽  
Temperate Climate ◽  
Climate Factors ◽  
Simple Effect ◽  
Soil Co2 Emissions ◽  
Precipitation Pulses ◽  
Mediterranean Conditions ◽  
Soil Temperature And Moisture

Soil CO2 emissions, the result of soil respiration processes, may be essential in climate change modelling. The complex phenomenon of soil respiration is regulated by a range of mainly climate-related environmental factors. We tested the latest published empirical models in a field experiment in an agricultural soil under Mediterranean conditions. Soil respiration was monitored biweekly with a portable infrared gas analyser, and climate features were monitored for 1 year (2010–11). An additional rewetting assay (watering the soil) was done at the end of the experiment in summer when the soil water content was dry. We tested different approaches to represent the simple effect of climate factors on soil respiration and found Gaussian models to be the best. We also tested the most recent models designed to represent the synergic effects of climate factors, and our modification of the Martin and Bolstad model showed the best coefficient of determination. The results suggest that linear approaches and the use of a fixed Q10 value should be revised to represent climate and soil respiration relations, especially in high-variability environments where soil respiration variability is controlled by soil temperature and moisture interactions, while precipitation pulses induce CO2 emission peaks. Finally, our results showed that the influence of soil temperature and moisture on soil respiration is lower under Mediterranean conditions than in temperate climate types.

Spatial and temporal effects of soil temperature and moisture and the relation to fine root density on root and soil respiration in a mature apple orchard

2010 ◽  
Vol 342 (1-2) ◽  
pp. 195-206 ◽  
Author(s):  
Christian Ceccon ◽  
Pietro Panzacchi ◽  
Francesca Scandellari ◽  
Luca Prandi ◽  
Maurizio Ventura ◽  
...  
Keyword(s):  
Soil Respiration ◽  
Soil Temperature ◽  
Fine Root ◽  
Apple Orchard ◽  
Root Density ◽  
Temporal Effects ◽  
Mature Apple ◽  
Fine Root Density ◽  
Soil Temperature And Moisture

Effects of Soil Temperature and Drought on Root–Soil Respiration in Apple under Field Conditions

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 453a-453
Author(s):  
Liqin Wang ◽  
David M. Eissenstat ◽  
Dora E. Flores-Alva
Keyword(s):  
Soil Moisture ◽  
Soil Respiration ◽  
Soil Temperature ◽  
Root Respiration ◽  
Hot Water ◽  
Field Conditions ◽  
Drought Treatment ◽  
Dry Soil ◽  
Heated Soil ◽  
Soil Temperature And Moisture

Root respiration is very important to root efficiency, root lifespan, and carbon cycling in plant ecosystems. Yet, the effects of soil temperature and moisture on root respiration are poorly understood, especially under field conditions. In this study, we manipulated soil temperature and moisture by six bearing `Red Chief' Delicious/M26 trees near State College, Pa. Soil temperature was elevated 5 °C at 5-cm depth using circulating hot water and stainless steel grids. Soil temperature was monitored using thermocouples and a data logger, and soil moisture was monitored using TDR. Root–soil respiration was determined by static trapping at the soil surface. Heating was conducted from 8 May to 28 Oct. Drought was initiated on 21 Aug. and lasted 2 months. Root–soil respiration was lowest in spring and increased from June to late August. After September, respiration decreased until the experiment ended in November. Root-soil respiration was not correlated with root length density. Heating enhanced root–soil respiration about 15% to 20% in spring (May) and 10% in summer (June–August). After the drought treatment began, heating increased root-soil respiration about 42% in wet soil, but did not influence respiration in dry soil. Heating accentuated the effect of the drought treatment on soil moisture. After 2 months of no irrigation and no rain, soil moisture was reduced 5% in unheated soil and 10% in heated soil. Drought slowed root–soil respiration 17% in unheated soil and 36% in heated soil, mainly because heating increased respiration in wet soil, but compared to the unheated treatment, had no effect in dry soil.

Does rhizosphere priming effect explain the greater soil respiration in well-watered and drought stressed maize?

2020 ◽  
Author(s):  
Khatab Abdalla ◽  
Mutez Ahmed ◽  
Johanna Pausch
Keyword(s):  
Soil Moisture ◽  
Soil Respiration ◽  
Soil Temperature ◽  
Root Exudates ◽  
Carbon Sink ◽  
Anthropogenic Activities ◽  
Agricultural Practice ◽  
Priming Effects ◽  
Soil Layers ◽  
Soil Temperature And Moisture

&lt;p&gt;The projected global warming risks due to high emissions of greenhouse gases, mainly from anthropogenic activities, increases the need for an agricultural practice with high carbon sink capacity and low water requirements without compromising on environment and productivity. On one hand, it&amp;#8217;s well accepted that soil moisture directly affects microbial activity, whereas on the other hand, drought stress was recently postulated to increase root exudates, which in turn will accelerate soil organic matter mineralization &amp;#8220;priming effects&amp;#8221;. Thus, the objective of this study was to investigate the interplay between soil moisture (well-watered and drought stressed) and maize (Zea mays L.) root exudates on soil CO&lt;sub&gt;2&lt;/sub&gt; efflux. The experiment consisted of three treatments, which are well-watered, drought stressed maize plus a control (without plants) lysimeters (1 m&lt;sup&gt;3&lt;/sup&gt;), Soil CO&lt;sub&gt;2&lt;/sub&gt; efflux, soil temperature and moisture content were measured weekly during the growing season (April to September) and monthly in the fallow period. Under well-watered conditions, the annual average of CO&lt;sub&gt;2&lt;/sub&gt; efflux was 0.12 g CO&lt;sub&gt;2&lt;/sub&gt;-C m&lt;sup&gt;-2&lt;/sup&gt; hr&lt;sup&gt;-1&lt;/sup&gt;, which was 24.5 and 20% significantly higher than under drought stressed and the control, respectively. Moreover, well-watered treatment had significantly greater primed carbon than drought stressed maize. Soil temperature in deeper soil layers (25, 50 and 75 cm) correlated positively (with the CO&lt;sub&gt;2&lt;/sub&gt; efflux, while soil moisture correlated negatively at the 5 cm and 25 cm. Overall, these results suggested that the root exudates decreased under drought conditions, which decreasing soil respiration. Drought tolerance varieties could be an option to decrease soil respiration and maintain productivity.&lt;/p&gt;

Sign in / Sign up

Export Citation Format

Share Document