Global soil organic carbon–climate interactions: Why scales matter

Wiley Interdisciplinary Reviews Climate Change, Journal Year: 2022, Volume and Issue: 13(4)

Published: June 2, 2022

Abstract Soil organic carbon (SOC) holds the largest terrestrial stock because of soil conditions and processes that favor persistence. Vulnerable to climate change, SOC may cross a tipping point toward liberating carbon‐based greenhouse gases, implying massive self‐amplifying SOC‐ interactions. Estimates persistence are challenging as we still lack broad mechanistic insights. Upscaling details from small larger scales is driving factors not available at needed resolution. Downscaling problematic many modeling studies highest uncertainties deriving response while models themselves have difficulties in replicating contemporary properties dynamics. To bridge problems scaling, strict process orientation seems adequate. Holdridge Life Zones (HLZ) classification, one example, classification framework mesoscale provides descriptive approach facilitate identification potential hotspots coldspots SOC‐climate interaction. Establishing coordinated experiments across all HLZ, but also including multiple global change drivers, has advance our understanding general principles regulating interaction Therefore, regionally tailored solutions for both urgently can lead better management ecosystem services provided. Improving “translations” relevant decision‐making key good predict fate stock. This article categorized under: Integrated Assessment Climate Change > Scenario Development

Language: Английский

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Benchmarking soil organic carbon to support agricultural carbon management: A German case study#

Journal of Plant Nutrition and Soil Science, Journal Year: 2022, Volume and Issue: 185(3), P. 427 - 440

Published: April 28, 2022

Abstract Background Soil organic carbon (SOC) storage is highly variable across sites and primarily depends on site properties land use. It therefore difficult for farmers to evaluate the actual SOC status of a site. To aid interpretation measured contents, easy‐to‐use frameworks assessment contents are needed. Aims The aim this study was derive site‐specific benchmarks German mineral soils under agricultural use based dataset first Agricultural Inventory. Methods stratified into 33 strata by use, soil texture, C/N ratio mean annual precipitation. Lower upper were calculated all (0.125 0.875 quantile). Results benchmark value ranges lower cropland (6.8–48.9 g kg –1 ) than grassland (14.1–76.6 ), increased with rising clay content Sandy wide high due their heathland or peatland history divided separate strata. number only decreased slightly. Around 15–20 required as minimum quantify one stratum. Conclusions presented framework easy requiring four readily available stratification factors perform comparative classification contents. allows extension services compare where fall within expected range site, can thus help develop an initial evaluation regard soil‐specific differences.

Language: Английский

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Biochemical composition of soil organic matter physical fractions under 32-year fertilization in Ferralic Cambisol

Carbon Research, Journal Year: 2023, Volume and Issue: 2(1)

Published: Jan. 11, 2023

Abstract Biochemical properties of soil organic matter (SOM) are fundamental for fertility and health. However, it is unclear how fertilization regime influences the biochemical compositions oxidation states SOM physical fractions. In this study, issue was studied under four 32-year amendment regimes: unfertilized control, urea (N), N + calcium dihydrogen phosphate potassium chloride (NPK), NPK plus manure (NPKM). Three fractions: coarse particulate (> 250 μm, cPOM), fine (53–250 fPOM) mineral-associated OM (< 53 MAOM) were separated measured by pyrolysis gas chromatography/mass spectrometry (Py-GC/MS). Compared with background in 1986, increased 10.6%, 14.2%, 23% 52% N, NPK, NPKM, respectively. The red here had not reached carbon saturation, because low conversion efficiency (6.8%) from input-carbon to (SOC). Physical size but type primarily regulated molecular composition, relative selective retention aromatics lignin both cPOM fPOM, whereas N-containing compounds (particularly amino-N) enriched MAOM due their high abilities adsorb minerals. C state also mainly dependent on size, highest value fPOM. sources its fractions, dominated microbial-derived (60–90%), independent fertilization. conclusion, arrangement (proxy microbial decomposition degree) played a more important role regulating features than initial quality various amendments. Graphical

Language: Английский

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Organic Carbon and Lignin Protection by Metal Oxides Versus Silicate Clay: Comparative Study Based on Wetland and Upland Soils

Journal of Geophysical Research Biogeosciences, Journal Year: 2023, Volume and Issue: 128(7)

Published: July 1, 2023

Abstract Mineral binding of organic carbon (OC) is one the key mechanisms promoting soil (SOC) persistence, which vital for long‐term sequestration atmospheric dioxide into soils. However, relative importance two main types minerals ‐ metal oxides and silicate clay—in SOC protection remains unclear, hampering our ability to predict protect this important pool persistent SOC. Here, we analyzed OC bound (OC ) versus clay in soils from contrasting environments (i.e., wetlands uplands) using sequential dissolution by dithionite hydrofluoric acid. We found that % was higher than both uplands, indicating dominance protection. The sum constituted a fraction suggesting an underappreciated role mineral (in particular, oxide) wetland preservation. Furthermore, lignin phenol analysis tandem, ∼23% phenols were additionally released after removal clay, providing potential means assess “hidden” matrices. Given wide use as tracers terrestrial plant‐derived OC, results suggest contribution or sedimentary stocks mineral‐protected deserves reassessment. These findings highlight differential various its components environments, warrants better recognition understanding distribution dynamics

Language: Английский

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Characteristics and factors influencing soil organic carbon composition by vegetation type in spoil heaps

Frontiers in Plant Science, Journal Year: 2023, Volume and Issue: 14

Published: Oct. 12, 2023

The variation of organic carbon content in spoil heaps is closely related to improving soil structure, maintaining fertility, and regulating cycling balance. Analyzing the driving factors during natural vegetation restoration process great significance for promoting accumulation heaps.we selected with same number years research variations components under different types (grassland: GL, shrubland: SL, secondary forest: SF) compared results those on bare land (BL).Our showed that type depth significantly affect components. There was no difference between SF but both were considerably superior GL BL (p<0.05), particulate (POC) light fraction (LFOC) contents SL highest. A significant positive linear correlation existed SOC active Pearson's redundancy analysis available potassium (AK) total nitrogen (TN) gravel (GC) impacted carbon. When present, TN, phosphorus (TP), Fine root biomass (FRB) Structural equation modelling (SEM) shows AK moisture (SMC) directly composition BL, there cover, fine had largest effect SEM. Soil bulk density (BD) has a negative impact carbon, especially presence vegetation.These findings suggest can increase content, FRB, AK, TN play important roles enhancing Supplementation should be considered stage, shrubs nitrogen-fixing functions well-developed roots are more beneficial

Language: Английский

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