Dynamics of the soil respiration response to soil reclamation in a coastal wetland

AbstractThe soil carbon (C) pools in coastal wetlands are known as “blue C” and have been damaged extensively owing to climate change and land reclamation. Because soil respiration (RS) is the primary mechanism through which soil carbon is released into the atmosphere at a global scale, investigating the dynamic characteristics of the soil respiration rate in reclaimed coastal wetlands is necessary to understand its important role in maintaining the global C cycle. In the present study, seasonal and diurnal changes in soil respiration were monitored in one bare wetland (CK) and two reclaimed wetlands (CT, a cotton monoculture pattern, and WM, a wheat–maize continuous cropping pattern) in the Yellow River Delta. At the diurnal scale, the RS at the three study sites displayed single-peak curves, with the lowest values occurring at midnight (00:00 a.m.) and the highest values occurring at midday (12:00 a.m.). At the seasonal scale, the mean diurnal RS of the CK, CT and WM in April was 0.24, 0.26 and 0.79 μmol CO2 m−2 s−1, and it increased to a peak in August for these areas. Bare wetland conversion to croplands significantly elevated the soil organic carbon (SOC) pool. The magnitude of the RS was significantly different at the three sites, and the yearly total amounts of CO2 efflux were 375, 513 and 944 g CO2·m−2 for the CK, CT and WM, respectively. At the three study sites, the surface soil temperature had a significant and positive relationship to the RS at both the diurnal and seasonal scales, and it accounted for 20–52% of the seasonal variation in the daytime RS. The soil water content showed a significant but negative relationship to the RS on diurnal scale only at the CK site, while it significantly increased with the RS on seasonal scale at all study sites. Although the RS showed a noticeable relationship to the combination of soil temperature and water content, the synergic effects of these two environment factors were not much higher than the individual effects. In addition, the correlation analysis showed that the RS was also influenced by the soil physico-chemical properties and that the soil total nitrogen had a closer positive relationship to the RS than the other nutrients, indicating that the soil nitrogen content plays a more important role in promoting carbon loss.

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Effects of Soil Temperature, Water Content, Species, and Fertilization on Soil Respiration in Bamboo Forest in Subtropical China

Forests ◽

10.3390/f11010099 ◽

2020 ◽

Vol 11 (1) ◽

pp. 99 ◽

Cited By ~ 1

Author(s):

Houxi Zhang ◽

Zhuangzhuang Qian ◽

Shunyao Zhuang

Keyword(s):

Soil Respiration ◽

Soil Temperature ◽

Water Content ◽

Management Practices ◽

Clay Content ◽

Bamboo Forest ◽

Subtropical China ◽

Bivariate Model ◽

Natural Factor ◽

Change Pattern

Understanding the change pattern of soil respiration (SR) and its drivers under different bamboo species and land management practices is critical for predicting soil CO2 emission and evaluating the carbon budget of bamboo forest ecosystems. A 24-month field study was performed in subtropical China to monitor SR in experimental plots of local bamboo (Phyllostachys glauca) without fertilization (PG) and commercial bamboo (Phyllostachys praecox) with and without fertilization (PPF and PP, respectively). The SR rate and soil properties were measured on a monthly timescale. Results showed that the SR rate ranged from 0.38 to 8.53 µmol CO2 m−2s−1, peaking in June. The PPF treatment had higher SR rates than the PP and PG treatments for most months; however, there were no significant differences among the treatments. The soil temperature (ST) in the surface layer (0–10 cm) was found to be the predominant factor controlling the temporal change pattern of the monthly SR rate in the PG and PP treatments (i.e., those without fertilization). A bivariate model is used to show that a natural factor—comprised of ST and soil water content (SWC)—explained 44.2% of the variation in the monthly SR rate, whereas biological (i.e., bamboo type) and management (i.e., fertilization) factors had a much smaller impact (less than 0.1% of the variation). The annual mean SR showed a significant positive correlation with soil organic matter (SOM; r = 0.51, P < 0.05), total nitrogen (TN; r = 0.47, P < 0.05), total phosphorus (TP; r = 0.60, P < 0.01), clay content (0.72, P < 0.05) and below-ground biomass (r = 0.60*), which altogether explain 69.0% of the variation in the annual SR. Our results indicate that the fertilization effect was not significant in SR rate for most months among the treatments, but was significant in the annual rate. These results may help to improve policy decisions concerning carbon sequestration and the management of bamboo forests in China.

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Spatial and seasonal variability of heterotrophic and autotrophic soil respiration in a winter wheat stand

Biogeosciences Discussions ◽

10.5194/bgd-7-9137-2010 ◽

2010 ◽

Vol 7 (6) ◽

pp. 9137-9173 ◽

Cited By ~ 10

Author(s):

N. Prolingheuer ◽

B. Scharnagl ◽

A. Graf ◽

H. Vereecken ◽

M. Herbst

Keyword(s):

Soil Respiration ◽

Winter Wheat ◽

Spatial Variability ◽

Soil Temperature ◽

Water Content ◽

Sampling Point ◽

Soil Organisms ◽

Area Index ◽

Temporal And Spatial Variability ◽

Temporal And Spatial

Abstract. Soil respiration (Rs), the sum of respiration by soil organisms (Rh) and roots (Ra), is known to be highly variable in both, space and time. There is less information available about the behaviour of Rh and Ra in time and particularly in space. The objective of this study was to quantify the contribution of each component to the temporal and spatial variability of soil respiration in a winter wheat stand. We measured soil respiration from March to July 2009 by closed-dynamic chambers for 61 sampling points in a 50×50 m plot in a winter wheat stand close to Jülich, Germany. Each sampling point was equipped with a 7 cm soil collar to measure total Rs and a 50 cm soil collar to exclude roots and to measure Rh only. Ra was assumed to equal Rs−Rh. Simultaneously, soil temperature and soil water content were measured in 6 cm depth. Biweekly the temporal development of the leaf area index was measured. On average, the heterotrophic contribution to Rs was 69% and thus higher than the autotrophic contribution. Seasonal changes of soil temperature and especially water content explained well the temporal variability of Rs (r2=0.74) and Ra (r2=0.80). Spatial variability of Ra was on average much higher (CV=88%) than the spatial variability of Rh (CV=30%). However, Rh was mainly randomly distributed in space, whereas Ra showed spatial autocorrelation. Spatial correlation and cross-variograms showed a significant spatial dependence of Rs on Ra. From our results we concluded that spatial variability of soil respiration in a winter wheat stand represented mainly the spatial variability of the autotrophic component.

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Variations in Soil Respiration at Different Soil Depths and Its Influencing Factors in Forest Ecosystems in the Mountainous Area of North China

Forests ◽

10.3390/f10121081 ◽

2019 ◽

Vol 10 (12) ◽

pp. 1081

Author(s):

Dandan Wang ◽

Xinxiao Yu ◽

Guodong Jia ◽

Wei Qin ◽

Zhijie Shan

Keyword(s):

Seasonal Variation ◽

Soil Respiration ◽

Soil Temperature ◽

Water Content ◽

Soil Water Content ◽

North China ◽

Forest Ecosystems ◽

Mountainous Area ◽

Forest Types ◽

Root Cutting

An in-depth understanding of the dominant factors controlling soil respiration is important to accurately estimate carbon cycling in forest ecosystems. However, information on variations in soil respiration at different soil depths and the influencing factors in forest is limited. This study examined the variations in soil respiration at two soil depths (0–10 and 10–20 cm) as well as the effects of soil temperature, soil water content, litter removal, and root cutting on soil respiration in three typical forest types (i.e., Pinus tabulaeformis Carrière, Platycladus orientalis (L.) Franco, and Quercus variabilis Bl.) in the mountainous area of north China from March 2013 to October 2014. The obtained results show that soil respiration exhibited strong seasonal variation and decreased with soil depth. Soil respiration was exponentially correlated to soil temperature, and soil respiration increased with soil water content until reaching threshold values (19.97% for P. tabulaeformis, 16.65% for P. orientalis, and 16.90% for Q. variabilis), followed by a decrease. Furthermore, interactions of soil temperature and water content significantly affected soil respiration at different soil depths of forest types, accounting for 68.9% to 82.6% of the seasonal variation in soil respiration. In addition to soil temperature and water content, aboveground litter and plant roots affected soil respiration differently. In the three forest types, soil respiration at two soil depths decreased by 22.97% to 29.76% after litter removal, and by 44.84% to 53.76% after root cutting. The differences in soil respiration reduction between the two soil depths are largely attributed to variations in substrate availability (e.g., soil organic content) and soil carbon input (e.g., litter and fine root biomass). The obtained findings indicate that soil respiration varies at different soil depths, and suggest that in addition to soil temperature and water content, soil carbon input and dissolved organic substances may exert a strong effect on forest soil respiration.

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Effects of Throughfall Exclusion on Soil Respiration in a Moso Bamboo Forest Soil in Southeast China

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.726-731.3762 ◽

2013 ◽

Vol 726-731 ◽

pp. 3762-3766

Author(s):

Qian Li ◽

Ben Zhi Zhou ◽

Xiao Ming Wang ◽

Xiao Gai Ge ◽

Yong Hui Cao

Keyword(s):

Soil Respiration ◽

Soil Temperature ◽

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Bamboo Forest ◽

Monthly Variation ◽

Exclusion Experiment ◽

Throughfall Exclusion ◽

And Control

Both soil temperature and soil water condition are important factors that influence soil respiration at different forest. In this study, a throughfall exclusion experiment was carried out to explore effects of increased soil temperature and decreased soil water content on soil respirations in the bamboo forest in North Zhejiang of China. The results showed that 1) monthly variation in soil respiration ranges from 2.00 to 0.63μmol·m-2·s-1 and 2.20 to 0.66μmolm-2s-1in throughfall exclusion and control plots respectively. The soil respiration monthly variation following the monthly variation of soil temperature and in contrast to the monthly soil water content. 2) Soil temperature can explain 65.5%and 73.9% of the variance of soil respiration in throughfall exclusion and control plots respectively. Multivariate linear model based on temperature and soil water content explained 66.9% and 73.4% of the variance of soil respiration in throughfall exclusion and control plots respectively. Soil water content had no significant relationship with soil respiration. Q10 values of throughfall exclusion and control plots were 5.99 and 4.44.

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Changes in soil carbon sequestration and emission in different succession stages of biological soil crusts in a sand-binding area

10.21203/rs.3.rs-258954/v1 ◽

2021 ◽

Author(s):

Bo Wang ◽

Jing Liu ◽

Xin Zhang ◽

Chenglong Wang

Keyword(s):

Soil Temperature ◽

Soil Carbon ◽

Water Content ◽

Desert Soil ◽

Desert Ecosystems ◽

Organic C ◽

Desert Soils ◽

Soil C ◽

C Cycle ◽

Spatio Temporal

Abstract Background We investigated the spatio-temporal dynamics of soil carbon dioxide (CO2) and soil methane (CH4)-flux during biological soil crust (BSC) deposition in a sand-binding area in the eastern Chinese Hobq Desert. The trends in soil organic carbon (C) content and density were analyzed during this process. The sampling sites comprised a mobile dune (control) and those with algal, lichen, and moss crust-fixed sands. The desert soil CO2 and CH4-flux, temperature, and water content were measured from May to October in 2017 and 2018. Simultaneously, organic C content and density were measured and analyzed by stratification. Results The spatio-temporal variation in desert soil CO2-flux was apparent. The average CO2- fluxes in the control, algal, lichen, and moss sites were 1.67, 2.61, 5.83, and 6.84 mmol·m− 2·h− 1, respectively, during the growing season, and the average CH4-fluxes in the four sites were − 1.13, -1.67, -3.66, and − 3.77 µmol·m− 2·h− 1, respectively. Soil temperature was significantly positively correlated with CO2-flux but could not influence CH4 absorption, and C flux had minimal correlation with soil water content. The soil total organic C density at all sites was significantly different and decreased as follows: moss > lichen > algal > control; moreover, it decreased with soil depth at all sites. The accumulation of desert soil organic C could enhance soil C emissions. Conclusion In a semi-arid deserts, artificial planting could promote sand fixation and BSC succession; therefore, increasing the C storage capacity of desert soils and decreasing soil C emissions could alter the C cycle pattern in desert ecosystems. Soil temperature is the major factor controlling desert soil CO2 flux and vegetation restoration, and BSC development could alter the response patterns of C emissions to moisture conditions in desert soils. The results provide a scientific basis for studying the C cycle in desert ecosystems.

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Ensuring the effects of climate warming; the sensitivity of controlling factors on soil respiration in Sub-Tropical grassland

Tropical Plant Research ◽

10.22271/tpr.2020.v7.i3.065 ◽

2020 ◽

Vol 7 (3) ◽

pp. 529-540

Author(s):

Deepa Dhital ◽

◽

Suman Prajapati ◽

Sanu Raja Maharjan ◽

Toshiyuki Ohtsuka ◽

...

Keyword(s):

Carbon Dioxide ◽

Soil Respiration ◽

Soil Temperature ◽

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Exponential Function ◽

Plant Biomass ◽

Carbon Dioxide Emission ◽

Tropical Grassland

Prevailing climate change is expected due to carbon dioxide emission to the atmosphere through soil respiration and perhaps the alteration in the terrestrial carbon cycle. The measurements to establish the effect and sensitivity of soil temperature, soil water content and plant biomass on soil respiration was performed in the sub-tropical grassland located in Central Nepal. Field measurements of soil respiration was conducted by using the closed-chamber method, and soil temperature, soil water content and plant biomass were monitored in the years 2015 and 2016. The soil respiration showed positive significant exponential function which accounted for 74.6% (R2=0.746, p<0.05) of its variation with the soil temperature. The temperature sensitivity of soil respiration, Q10 value obtained was 2.68. Similarly, soil respiration showed a positive significant exponential function that accounted for 37.2% (R2=0.372, p<0.05) of its variation with the soil water content. Remarkable seasonal and monthly variations were observed in soil respiration, soil temperature and soil water content, and the plant biomass as well followed the seasonal trend in variation of the soil respiration. Average soil respiration during measurements period was observed 325.51 mg CO2 m-2 h-1 and the annual soil respiration of the grassland in the years 2015 and 2016 was estimated 592.35 g C m-2 y-1. The study confirmed that soil temperature is the most influential primary factor in controlling soil respiration along with the soil water content and plant biomass. This research indicates that through emissions under the increasing temperature and precipitation, in the changing climate, the sub-tropical grassland could be an additional source of carbon dioxide to the atmosphere that might spur risk for further warming.

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Soil Respiration Dynamics in Bromus erectus-Dominated Grasslands under Different Management Intensities

Agriculture ◽

10.3390/agriculture10010009 ◽

2019 ◽

Vol 10 (1) ◽

pp. 9 ◽

Cited By ~ 1

Author(s):

Matteo Francioni ◽

Laura Trozzo ◽

Marco Toderi ◽

Nora Baldoni ◽

Marina Allegrezza ◽

...

Keyword(s):

Climate Change ◽

Soil Respiration ◽

Soil Temperature ◽

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Short Term ◽

Intensive Use ◽

Main Driver ◽

Bromus Erectus

Reduction of soil greenhouse gas emissions is crucial to control increases in atmospheric CO2 concentrations. Permanent grasslands are of considerable importance in climate change mitigation strategies as they cover about 13% of the global agricultural area. However, uncertainties remain for the effects of management practices on soil respiration, especially over the short term. This study investigated the influence of different mowing intensities on soil respiration over the short term for Bromus erectus-dominated grasslands in the central Apennines. From 2016 to 2018, soil respiration, temperature, and moisture were measured under three different management systems: customary management, intensive use, and abandonment. Both soil water content and temperature changed over time, however mowing did not affect soil water content while occasionally altered soil temperature. The intensive use promoted higher seasonal mean soil respiration compared to the abandonment only during the 2016 growing season. Soil temperature was the main driver of soil respiration above a soil water content threshold that varied little among treatments (18.23–22.71%). Below the thresholds, soil moisture was the main driver of soil respiration. These data suggest that different mowing regimes have little influence on soil respiration over the short term in Bromus erectus-dominated grasslands. Thus, more intensive use would not have significative impacts on soil respiration, at least over the short term. Future studies need to clarify the role of root mycorrhizal and microbial respiration in the light of climate change, considering the seasonal redistribution of the rainfall.

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