Soil CO2 respiration: Comparison of chemical titration, CO2 IRGA analysis and the Solvita gel system

AbstractThe measurement of soil carbon dioxide respiration is a means to gauge biological soil fertility. Test methods for respiration employed in the laboratory vary somewhat, and to date the equipment and labor required have somewhat limited more widespread adoption of such methodologies. The purpose of this research is to compare the results of measured soil CO2 respiration using three methods: (1) titration method; (2) infrared gas analysis (IRGA); and (3) the Solvita gel system for soil CO2 analysis. We acquired 36 soil samples from across the USA for comparison, which ranged in pH from 4.5 to 8.5, organic C from 0.8 to 4.6% and the clay content from 6 to 62%. All three methods were highly correlated with each other after 24-h of incubation (titration and Solvita r2=0.82, respirometer and Solvita r2=0.79 and titration versus respirometer r2=0.95). The 24-h (1-day) CO2 release from all three methods was also highly correlated to both basal soil respiration (7–28 days) and cumulative 28-day CO2 respiration. An additional 24 soil samples were acquired and added to the original 36, for a total of 60 soil samples. These samples were used for calibration of the Solvita gel digital color reader results using CO2-titration results and regression analysis. Regression analysis resulted in the equation y=20.6∗(Solvita number)−16.5 with an r2 of 0.83. The data suggest that the Solvita gel system for soil CO2 analysis could be a simple and easily used method to quantify soil microbial activity. Applications may also exist for the gel system for in situ measurements in surface gas chambers. Once standardized soil sampling and laboratory analysis protocols are established, the Solvita method could be easily adapted to commercial soil testing labs as an index of soil microbial activity.

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Unexpected results in Chernozem soil respiration while measuring the effect of a bio-fertilizer on soil microbial activity

F1000Research ◽

10.12688/f1000research.12936.2 ◽

2017 ◽

Vol 6 ◽

pp. 1950 ◽

Cited By ~ 2

Author(s):

Gabriela Bautista ◽

Bence Mátyás ◽

Isabel Carpio ◽

Richard Vilches ◽

Karina Pazmino

Keyword(s):

Soil Respiration ◽

Moisture Content ◽

Sustainable Agriculture ◽

Microbial Activity ◽

Environmental Quality ◽

Soil Microbial Activity ◽

Soil Samples ◽

Chernozem Soil ◽

Soil Microbial ◽

Optimal Moisture Content

The number of studies investigating the effect of bio-fertilizers is increasing because of their importance in sustainable agriculture and environmental quality. In our experiments, we measured the effect of different fertilizers on soil respiration. In the present study, we were looking for the cause of unexpected changes in CO2 values while examining Chernozem soil samples. We concluded that CO2 oxidizing microbes or methanotrophs may be present in the soil that periodically consume CO2 . This is unusual for a sample taken from the upper layer of well-ventilated Chernozem soil with optimal moisture content.

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Comparison of heat output and CO2 respiration to assess soil microbial activity: a case of ultisol soil

Plant Soil and Environment ◽

10.17221/168/2018-pse ◽

2018 ◽

Vol 64 (No. 10) ◽

pp. 470-478 ◽

Cited By ~ 1

Author(s):

Jia Xiuhong ◽

Cao Haichuan ◽

Jiang Lanlan ◽

Yuan Jihong ◽

Zheng Shixue

Keyword(s):

Microbial Communities ◽

Microbial Activity ◽

Total Phospholipid ◽

Chemical Properties ◽

Soil Microbial Activity ◽

Soil Samples ◽

Heat Output ◽

Mineral N ◽

Soil Microbial ◽

Comprehensive Indicator

Glucose-induced microcalorimetry and carbon dioxide (CO2) production are two widely applied methods to assess microbial activity in soil. However, the links among them, microbial communities and soil chemical properties based on large number of soil samples are still not fully understood. Seventy-two soil samples of different land uses were collected from an ultisol soil area in south China. The best correlation between the rate of heat output and the rate of CO2 respiration occurred in 8–16 h reaction (R2 = 0.64), followed by 0–8 h (R2 = 0.50) (P < 0.001). However, the correlations decreased sharply after 16 h. The heat output per biomass unit (QT/MBC) was well correlated with the total phospholipid fatty acids (PLFAs) (R2 = 0.56) and bacterial PLFAs (R2 = 0.53) (P < 0.001). In contrast, these links were not apparent between soil respiratory quotient (qCO2) and the total PLFAs and microbial communities. Redundancy analysis further confirmed that QT/MBC was a more comprehensive indicator to assess soil microbial activity and soil quality than qCO2, showing a good negative correlation to soil organic carbon, total nitrogen (N) and mineral N, and pH. This work is very helpful to better guide the application of calorimetry and CO2 respiration in assessing microbial activity in soils.

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Unexpected results in Chernozem soil respiration while measuring the effect of a bio-fertilizer on soil microbial activity

F1000Research ◽

10.12688/f1000research.12936.1 ◽

2017 ◽

Vol 6 ◽

pp. 1950

Author(s):

Gabriela Bautista ◽

Bence Mátyás

Keyword(s):

Soil Respiration ◽

Moisture Content ◽

Sustainable Agriculture ◽

Microbial Activity ◽

Environmental Quality ◽

Soil Microbial Activity ◽

Soil Samples ◽

Chernozem Soil ◽

Soil Microbial ◽

Optimal Moisture Content

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Salinity affects the response of soil microbial activity and biomass to addition of carbon and nitrogen

Soil Research ◽

10.1071/sr12191 ◽

2013 ◽

Vol 51 (1) ◽

pp. 68 ◽

Cited By ~ 16

Author(s):

Manpreet S. Mavi ◽

Petra Marschner

Keyword(s):

Wheat Straw ◽

Microbial Activity ◽

Negative Impact ◽

Soil Microbial Activity ◽

Microbial Biomass C ◽

Organic C ◽

Soil Microbial ◽

C And N ◽

Microbial Tolerance ◽

Tolerance To Salinity

Addition of carbon (C) and nitrogen (N) to soil can enhance microbial tolerance to salinity, but it is not known if salinity changes the response of microbial activity and biomass to addition of C and N, or how nutrient addition affects microbial tolerance to salinity. We prepared salinity treatments of non-saline soil [electrical conductivity (EC1 : 5) 0.1 dS m–1] without salt addition or adjusted to four salinity levels (2.5, 5.0, 7.5, 10 dS m–1) using a combination of CaCl2 and NaCl. The soils were amended with 2.5 mg C g–1 as glucose or as mature wheat straw (C/N ratio 47 : 1), with NH4Cl added to glucose to achieve a C/N ratio similar to that of wheat straw, or with NH4Cl added to glucose or wheat straw to achieve a C/N ratio of 20. Soil respiration was measured over 30 days. Microbial biomass C and N (MBC, MBN), dissolved organic C (DOC), and total dissolved N (TDN) were measured on day 30. Cumulative respiration and MBC concentration decreased with increasing EC, less so with glucose than with wheat straw. The MBC concentration was more sensitive to EC than was cumulative respiration, irrespective of C source. Addition of N to glucose and wheat straw to bring the C/N ratio to 20 significantly decreased cumulative respiration and MBC concentration at a given EC. This study showed that in the short term, addition of a readily available and easily decomposable source of energy improves the ability of microbes to tolerate salinity. The results also suggest that in saline soils, irrespective of the C substrate, N addition has no impact, or a negative impact, on microbial activity and growth.

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Evaluation of Soil Microbial Activity and Maize (Zea mays L.) Growth in Soil Amended with Composted Agroindustrial Wastes

ISPEC Journal of Agricultural Sciences ◽

10.46291/ispecjasvol4iss2pp99-113 ◽

2020 ◽

Vol 4 (2) ◽

pp. 99-113

Author(s):

Huseyin Husnu KAYIKCIOGLU ◽

Nur OKUR

Keyword(s):

Microbial Activity ◽

Soil Microbial Activity ◽

The Other ◽

Maize Plant ◽

Control Soil ◽

Total N ◽

Organic C ◽

Amended Soils ◽

Soil Microbial ◽

Tobacco Waste

The present study was performed to emphasize that tobacco waste compost can be used as an organic material resource in soils under semi-arid climate conditions. We determined soil microbial activity as well as the contents of the nutrition and the biomass of maize plant to indicate which compost is the most suitable one for decomposing by microorganisms in the soil. In the greenhouse experiment, the treatments consisted of tobacco waste compost (TWC), tobacco waste+olive pomace compost (TWOPC), tobacco waste+grape pomace compost (TWGPC), tobacco waste+ farmyard manure compost (TWFYC), inorganic fertilization (NPK) and control soil. Soil respiration was higher in TWC amended soils, followed by TWOPC, TWGPC and TWFYC amended soils compared to non-amended soils. The effect of compost applications on enzyme activity of soil was significant. The activities of protease, urease and dehydrogenase were significantly higher in the soil amended with TWC as compared to those of the other composts. Β-Glucosidase activity was highest (21 %) in TWOPC with respect to control soil. Aryl sulphatase activity in the soils amended with the composts increased between 20 to 26 % with respect to the control. Activity of alkaline phosphatase in soils amended with the composts was not different from the amount obtained for control soil. The maximum values of leaf N, K and biomass weight of maize plant were found in inorganic fertilizer treatment (NPK). The biomass weight increased 115 % and 83 %, respectively, in NPK and TWC treatments compared to the control soil. The results suggested that application of the composts including tobacco waste to soil at a rate of 30 t ha-1 increased the amounts of microbial activity, organic C, available P and K in soil. On the other hand, the amount of total N in the composts is not enough for the growth of maize plant.

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Evaluating carbon dynamics and microbial activity in arctic soils under warmer temperatures

Canadian Journal of Soil Science ◽

10.4141/cjss07060 ◽

2008 ◽

Vol 88 (1) ◽

pp. 31-44 ◽

Cited By ~ 12

Author(s):

Maren Oelbermann ◽

Michael English ◽

Sherry L Schiff

Keyword(s):

Microbial Activity ◽

Soil Microorganisms ◽

Microbial Respiration ◽

Soil Microbial Activity ◽

Phase 2 ◽

Metabolic Diversity ◽

Soil Horizons ◽

Organic C ◽

Soil Microbial ◽

Arctic Soils

A large portion of carbon (C) is stored in the world’s soils, including those of peatlands, wetlands and permafrost. However, there is disagreement regarding the effects of climate change on the rate of organic matter decomposition in permafrost soils of the arctic. In this study it was hypothesized that soil exposed to a higher ambient temperature would have a greater flux of CO2 as well as a change in the metabolic diversity of culturable soil microorganisms. To evaluate this hypothesis we determined soil C dynamics, soil microbial respiration and activity, and 13C and 15N fractionation in laboratory incubations (at 14 and 21°C) for an organic-rich soil (Mesic Organic Cryosol) and a mineral soil (Turbic Cryosol) collected at the Daring Lake Research Station in Canada’s Northwest Territories. Soil organic C (SOC) and nitrogen (N) stocks (g m-2) and concentration (%) were significantly different (P < 0.05) between soil horizons for both soil types. Stable isotope analysis showed a significant enrichment in δ13C and δ15N with depth and a depletion in δ13C and δ15N with increasing SOC and N concentration. In laboratory incubations, microbial respiration showed three distinct phases of decomposition: a phase with a rapidly increasing rate of respiration (phase 1), a phase in which respiration reached a peak midway through the incubation (phase 2), and a phase in the latter part of the incubation in which respiration stabilized at a lower flux than that of the first phase (phase 3). Fluxes of CO2 were significantly greater at 21°C than at 14°C. The δ13C of the evolved CO2 became significantly enriched with time with the greatest enrichment occurring in phase 2 of the incubation. Soil microbial activity, as measured using Biolog EcoplatesTM, showed a significantly greater average well color development, richness, and Shannon index at 21°C; again the greatest change occurred in phase 2 of the incubation. Principal component analysis (PCA) of the Biolog data also showed a change in the distinct clustering of the soil microbial activity, showing that C sources from the soil were metabolized differently with time at 21 than at 14°C, and between soil horizons. Our results show that Canadian arctic soils contain large stores of C, which readily decompose, and that substantial increases in CO2 emissions and changes in the metabolic diversity of culturable soil microorganisms may occur when ambient temperatures increase from 14 to 21°C. Key words: CO2 flux, C fractionation, global warming, soil organic C and N, stable isotopes

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