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Soil – the largest terrestrial pool of actively-cycling carbon – has the potential to sequester vast amounts of carbon globally. Chemical- and physical-associations of organic matter with mineral surfaces are known to play a critical role in this storage and preservation. However, the maximum capacity of soils to store carbon globally, and the role of mineralogy in driving this limit and its spatial variation, is still unknown. Here we present a comprehensive analysis of mineral-associated carbon and auxiliary variables from sites that span diverse biomes and soil types. We find that soil mineralogical properties dictate the maximum capacity of soils to stabilize organic matter associated with minerals, and that this mineral-associated organic matter accounts for the majority of carbon and nitrogen in soil organic matter. Explicit representations of mineral-organic associations are still lacking in Earth system models, and our findings are essential for informing and parameterizing model formulations at global scales. Our results suggest that most soils contain substantially less carbon than their mineral-associated carbon capacity (i.e., they are below carbon saturation), and that this is particularly evident in deeper soils and in poorly-managed and degraded lands. We calculate the mineralogical limit of low- and high-activity mineral soils to stabilize carbon, and use these empirically-derived limits to estimate the global potential for soil minerals to stabilize carbon. This estimate, and the underlying spatial distribution, provides crucial insights and motivation for targeted soil management and conservation efforts. Increasing soil carbon storage through restoration is a promising avenue for mitigating global emissions with lasting co-benefits. [ABSTRACT FROM AUTHOR]

Soil inorganic carbon (SIC) accounts for 30–70% of the total soil C in global drylands. Despite the slow turnover rate, recent studies indicate that SIC could be altered by land-use change as soil organic C (SOC). Neglecting SIC change could contribute greatly to the uncertainty of soil C dynamics in drylands. However, due to the spatial-temporal variation in SIC, the direction and magnitude of SIC change (rate) induced by land-use change at a large spatial scale is understudied and poorly understood. Here, we used the space-for-time approach to test how the SIC change varied with the duration and type of land-use change and soil depth across China's drylands. We assessed the temporal and spatial variations in the SIC change rate and explored the influencing factors based on a regional dataset comprising 424 pairs of data across North China. We found that the SIC change rate of 0–200 cm after land-use change was 12.80 (5.47‒20.03) g C m−2 yr−1 (mean with 95% confidence interval), which was comparable to the SOC change rate (14.72, (5.27-24.15 g C m−2 yr−1)). Increased SIC occurred only in deep soils (>30 cm) and in the conversion from deserts to croplands or woodlands. In addition, the SIC change rate decreased with the duration of land-use change, implying that quantifying the temporal pattern of SIC change is necessary to accurately estimate SIC dynamics. The SIC change was strongly related to changes in soil water content. The SIC change rate was weakly and negatively correlated with the SOC change rate, and this relationship varied with soil depth. Together, this study highlights that to improve the prediction of soil C dynamics following land-use change in drylands, we should quantify the temporal and vertical patterns of both soil inorganic and organic C changes in the region. [Display omitted] • Inorganic C of deep soils increased after land-use change across China's drylands. • The SIC change rate displayed a decreasing trend with duration of land-use change. • The SIC change rates after land-use change were comparable to the SOC change rates. • SIC changes were negatively and weakly correlated with SOC changes. [ABSTRACT FROM AUTHOR]

Straw return as a common and effective management can improve soil carbon (C) sequestration and structure by forming aggregates and aggregate associated C. Quantifying soil aggregation and aggregate associated C is key to predicting soil organic C dynamics using testable models. The relative quantity of C stabilized in soil aggregate is an indicator that can reveal the conversion efficiency of added straw to organic C in aggregate. Straw size is known to alter litter decomposition, but how straw size impacts the dynamics of soil aggregate formation and the relative quantity of C stabilized in soil aggregate after litter addition is not well understood. We conducted an 80-day laboratory incubation with wheat straw addition of two different sizes (1–2 mm and <0.25 mm) to artificial soils of two textures (3 % clay and 7 % clay). The objectives were to examine 1) whether straw size significantly modified litter decomposition and the relative quantity of C stabilized in soil aggregates over time, and 2) what soil physical and biochemical factors determined soil aggregation and the formation of aggregate-associated C over time, such as straw size, soil texture, or enzyme activity. We found that both litter decomposition and the relative quantity of C stabilized in soil aggregates were higher in the treatment with small straw addition than those with large straw addition, but they were not significantly different between two soils with 3 % vs. 7 % clay content. This was due to increased enzyme activities caused by small straw addition, which could enhance dissolved organic C generation and stimulate microbial decomposition. Additionally, the mass proportion of macroaggregate (>2 mm) increased with time while the mass proportion of microaggregate (0.25–2 mm) decreased, suggesting that microaggregate combined to form macroaggregate (>2 mm) in the late stage of incubation (after day 17). Moreover, the relative quantity of C stabilized in microaggregate (<0.053 mm) increased linearly with dissolved organic C, whereas the relative quantity of C stabilized in macroaggregate (>2 mm) increased with the aromaticity of dissolved organic matter as measured by specific ultraviolet absorbance at 254 nm. Together, our findings suggest that straw size remarkably modifies litter decomposition and the relative quantity of C stabilized in soil aggregates by changing the quantity and quality of dissolved organic C at different decomposition stages, whereas small difference in soil clay content has no effects. ● The relative quantity of carbon stabilized in aggregates was higher with small-straw addition than with large-straw addition. ● The relative quantity of carbon stabilized in micro- and macro-aggregates showed opposite trends with time. ● Enzymatic activities were positively related to CO 2 respiration rate after straw addition. ● Dissolved organic C was positively related to the relative quantity of C stabilized in microaggregate (<0.053 mm). ● SUVA 254 was positively related to the relative quantity of C stabilized in large macroaggregate (>2 mm). [ABSTRACT FROM AUTHOR]

• Soil organic carbon (C) content exhibits an increasing trend with elevation (from 481 to 3035 m) in arid regions. • Exchangeable Ca2+ predominantly governs soil organic C content at high elevations. • Amorphous iron is the most important predictor of soil organic C content at low elevations. • Soil Ca2+ competes with iron at high elevations but assists iron at low elevations for organic C stabilization. Elevational gradients offer powerful natural experiments for testing how soil organic carbon (SOC) responds to environmental changes (e.g., climate, plant inputs, and soil geochemistry) across a wide range. Exchangeable calcium (Ca ex) emerges as an important geochemical driving factor of SOC content in arid regions, yet its significance in regulating SOC content across climatic gradients remains poorly understood. Here, we assessed the relative importance of climate variables, plant inputs, and geochemical properties in controlling SOC content along a 2,500-m elevational gradient in the Tianshan Mountains. We explored the roles of Ca ex in regulating the interactions between iron (Fe)-(hydro)oxides and SOC content. We found that soil Ca ex (i.e., Na 2 SO 4 -extracted), likely controlled by biological cycling, was the major contributor to SOC content in cold and wet climatic conditions (1,400–3,035 m a.s.l.), where soils had relatively high Fe o and low pH (5.8‒7.9). In contrast, amorphous Fe, not Ca ex , was the most important regulator for SOC content in warm and dry climatic conditions (481–1,240 m a.s.l.) with Ca-rich and high pH soils (7.6‒9.0). Moreover, the results of partial correlation analysis suggested that Ca ex competed with Fe-(hydro)oxides in modulating SOC content in cold and wet climatic conditions due to low soil pH, but facilitated SOC stabilization by Fe-(hydro)oxides in warm and dry climatic conditions. Although climatic variables and plant inputs were significantly associated with SOC content, our findings indicated that Ca ex and Fe-(hydro)oxides had divergent controls over SOC content across climatic gradients in arid regions, depending on soil pH level. Our study reveals new insights on the potential role of cations in complexation of organic matter with minerals across a wide range of environmental conditions in the field. [Display omitted] [ABSTRACT FROM AUTHOR]

• Electrolyte is optimized for low-temperature LiFePO 4 -graphite battery. • Multi-component solvent system improves the ionic conductivity at low temperature. • Film-forming additives promote the formation of solid electrolyte interface film. • The optimized battery exhibits excellent performance at low temperatures. The design of electrolyte is crucial to improve the low temperature electrochemical performance of the LiFePO 4 -graphite battery. In this paper, by optimizing the solvent composition and introducing film-forming additives in the electrolyte, the low temperature performance of the battery is significantly improved. In detail, the EP (ethyl propionate) solvent with low melting point and low viscosity is added to the original EC (ethylene carbonate)-EMC (ethyl methyl carbonate)-DMC (dimethyl carbonate) solvent systems, which improved the ionic conductivity of the electrolyte, especially at low temperature (−40 °C). On the other hand, the introduction of FEC (fluoroethylene carbonate)/DTD (ethylene sulfate) film-forming agents promotes the formation of SEI (solid electrolyte interface) film, and the SEI is thin and uniform. As a result, the LiFePO 4 -graphite battery exhibits high capacity and long cycle life under low temperature conditions. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) can be defined by measurable chemical and physical pools, such as mineral-associated carbon, carbon physically entrapped in aggregates, dissolved carbon, and fragments of plant detritus. Yet, most soil models use conceptual rather than measurable SOC pools. What would the traditional pool-based soil model look like if it were built today, reflecting the latest understanding of biological, chemical, and physical transformations in soils? We propose a conceptual model-the Millennial model-that defines pools as measurable entities. First, we discuss relevant pool definitions conceptually and in terms of the measurements that can be used to quantify pool size, formation, and destabilization. Then, we develop a numerical model following the Millennial model conceptual framework to evaluate against the Century model, a widely-used standard for estimating SOC stocks across space and through time. The Millennial model predicts qualitatively similar changes in total SOC in response to single factor perturbations when compared to Century, but different responses to multiple factor perturbations. We review important conceptual and behavioral differences between the Millennial and Century modeling approaches, and the field and lab measurements needed to constrain parameter values. We propose the Millennial model as a simple but comprehensive framework to model SOC pools and guide measurements for further model development. [ABSTRACT FROM AUTHOR]

The understanding of soil microbial resource limitation has important implications for belowground nutrient cycling. Climate is a primary factor that regulates microbial resource limitation directly and indirectly. Elevational gradient has been used as a substitution of latitudinal gradient in ecological studies because the former displays a wide range of climate variation as the latter. However, whether the elevational trend of microbial resource limitation follows that of latitudinal pattern is still not well known. Here we aimed to 1) test the elevational patterns (465–3035 m a.s.l.) of microbial carbon (C) and nutrient (P: N) limitations in the Tianshan Mountain by using the enzymatic vector analysis, and 2) examine the importance of microclimate and soil resource in regulating microbial C and P:N limitation along the elevational gradient. We found that microbial C limitation generally decreased and microbial P:N limitation increased with increasing elevation, which were the opposite to those of latitudinal patterns. Our results further indicated that microbial C limitation was primarily controlled by soil microclimate with soil moisture alleviating microbial C limitation in the warm & dry climatic condition (465–1240 m a.s.l.) but intensifying in the cold & wet climatic condition (1400–3035 m a.s.l.). Microbial P:N limitation was mainly regulated by soil available P and by the shared effects of soil microclimate and resource. Moreover, microbial C limitation was negatively correlated with microbial P:N limitation, which implied that soil C and nutrient supplies were strongly coupled. Overall, the spatial changes of microbial resource limitation cannot be simply inferred from latitude to altitude or vice versa, instead we should focus on how the determinants of microbial resource limitation change along these environmental gradients. [ABSTRACT FROM AUTHOR]

A NS-C@b-MoS 2 hybrid is readily fabricated with bilayer MoS 2 molecules grafted onto 3D N/S doped carbon capsule skeleton in one tailored spatial-chemical doubly confined mode. The MoS 2 bilayer can expose more S-Mo-S bonds to adsorb K-ions. Together with the support effect of carbon skeleton, consequently, this NS-C@b-MoS 2 hybrid electrode achieves an ultra-fast and ultra-stable potassium-ion storage capability. [Display omitted] • A tailored induced vapour-deposition strategy to construct a MoS 2 /C hybrid. • MoS 2 with bilayer structure can expose more S-Mo-S bonds to adsorb K-ions. • One spatial-chemical doubly confined mode to enhance the MoS 2 bilayer stability. • The assembled PIC deliver an ultra-stable performance up to 65,000 cycles. Few-layers MoS 2 -based materials have a comprehensive advantage in accommodating potassium-ions due to the rich active S-Mo-S sites and rapid ionic dynamics. Unfortunately, the serious self-stacking of MoS 2 molecular layer resulted in insufficient space to buffer the stress/strain caused by K-ions intercalation, which makes MoS 2 -based electrode exhibits low capacitance and poor cyclic stability in practical studies. To solve this, an in situ induced deposition strategy is proposed to construct a MoS 2 /C hybrid (labelled as NS-C@b-MoS 2). In this NS-C@b-MoS 2 hybrid, the MoS 2 molecular with bilayer structure is grafted onto a 3D N/S dual-doping carbon skeleton in one spatial-chemical doubly confined mode. This unique hybrid mode not only expose more S-Mo-S bonds to adsorb K-ions, but also avoid the structural collapse of electrode by spatial-chemical doubly confinement effect of carbon skeleton. Consequently, the resultant NS-C@b-MoS 2 anode delivers a high specific capacity of 451.2 mAh g−1 at 0.1 A g−1 and an ultra-long cycle stability up to 20,000 cycles with only 0.0013 % fading per cycle. Moreover, the assembled NS-C@b-MoS 2 //NSAC potassium-ion capacitor delivers a high energy density of 126.5 Wh kg−1 and retains 55.2 Wh kg−1 after 65,000 cycles at 3800 W kg−1, which over the state-of-the-art reported performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • The OPID approach, could determine an OPtimal Incubation Duration for ongoing incubation experiment. • SOC decomposability were underestimated or overestimated when incubation period was short. • The accuracy of model projections increases with incubation period but diminishes when longer than an optimum. • Model performs better under lower temperature but reversed with increasing incubation period. Laboratory incubation is a commonly used method to measure the decomposition of soil organic carbon (SOC). While incubation experiments are conducted across a wide range of durations that may vary from hours to years, no method is available to determine an optimal duration of the incubation experiment so that SOC decomposition can be best understood. Here we presented a novel approach to determine the optimal duration called OPtimal Incubation Duration (OPID). The OPID approach quantifies information gained from an ongoing incubation experiment and determines the time point when SOC decomposition rates can be well quantified. Statistically, the OPID approach is based on a progressive data assimilation algorithm that iteratively assimilates data from an ongoing incubation experiment into a three-pool first-order SOC decomposition model. Using a published incubation data set under different temperatures as a case study, we first generated synthetic daily data, and then fed the data into the three-pool model iteratively to observe the changes of model performance. We found that the accuracy of model projections increased with incubation period and exhibited a trade-off between initial model performance and the time towards accurate projection among different temperatures of incubation. The optimal incubation duration was 347, 212, and 126 days under incubation temperatures of 15 °C, 25 °C and 35 °C, respectively. Comparing the parameters with which from the synthetic daily data, if the incubation period was shorter than the optimal durations, then the decomposition rate of the fast-turnover pool was underestimated and those of the slow pools were overestimated. Sensitivity analysis indicated that optimal incubation duration was negatively correlated with proportion of slow-turnover carbon pools, turnover rates, and initial carbon content, respectively. Our study suggested that long-term incubation experiments are necessary for capturing the dynamics of slow-turnover carbon pools. However, the additional data may not be helpful for model performance if the incubation duration is longer than the optimum. Our study provides a tool for soil scientists to design more effective incubation experiments. DA: data assimilation; PDA: progressive data assimilation; Cum CO 2 : cumulative CO 2 emission from soil; opt: optimal duration; [ABSTRACT FROM AUTHOR]

[Display omitted] • Microbial specific growth rates, active microorganisms portion and enzyme activity increase with cropland abandonment. • Microbial community shifts from K - to r -strategy with cropland abandonment. • Enzyme production increases with microbial growth and the portion of active microorganisms. • Microbial carbon use efficiency is directly affected by soil organic C content, pH, and the portion of active microorganisms. Microorganisms are critical for litter decomposition, organic carbon (C) and nutrient transformations in soil, corresponding to the vegetation succession. The dynamics of microbial activities and ecological functions during the soil recovery after agricultural land use (post-agricultural restoration) remains unclear. We investigated the effects of vegetation and soil restoration duration on active microbial biomass, microbial growth rates, C use efficiency (CUE, analyzed by 14C glucose utilization), and enzyme activities in three soil types of Russia: Haplic Luvisol in a deciduous forest (chronosequence from 0 to 37 years), Luvic Phaeozem in forest steppe (0–66 years), and Haplic Phaeozem in forest steppe (0–42 years). The microbial CUE (0.66–0.82) decreased during restoration and was highly dependent on soil type: the lowest in Luvisol and the highest in Haplic Phaeozem. The activities of β-1,4-glucosidase, β-1,4-N-acetylglucosaminidase, leucine aminopeptidase, and acid phosphatase increased during post-agricultural restoration. Microbial growth rates and the proportion of active microorganisms increased with restoration, reflecting a shift of microbial community to fast-growing decomposers (mainly r strategists) caused by large litterfall from recovered natural vegetation. The increase of the portion of active microorganisms and microbial growth rates was correlated with activities of enzymes responsible for C, N and P cycling. In conclusion, the post-agricultural restoration activates microorganisms, raises microbial growth, increases enzyme activities and accelerates microbially-mediated C and nutrient turnover. [ABSTRACT FROM AUTHOR]

[Display omitted] • SOM was mostly derived from plant litter rather than microbial residues. • SOM was associated with vermiculite via surface adsorption. • SOM was associated with illite and kaolinite through pore entrapment. • More plant carbohydrates were associated with 2:1 rather than 1:1 clay minerals. • SOM formation efficiency was affected by clay mineral type more than by plant litter type. Plant litters incorporated in soils are decomposed by microorganisms and partially transformed into soil organic matter (SOM) through mineral-organic association and physical protection in soil aggregates. Few studies have linked the effects of clay mineralogy and plant litter quality on controlling the formation efficiency of SOM. Using model soils, the objectives of this study were (1) to determine the effects of clay mineral type and plant litter quality on soil respiration dynamics, and formation efficiency of SOM, physical fractions, and chemical and microbial compositions of SOM at the end of a 120-day incubation; (2) to unravel SOM protection mechanisms and extents by specific clay minerals; and (3) to understand the key role of clay minerals relative to plant litter quality in controlling SOM formation. The changes in X-ray diffraction peak intensity (in terms of peak height) of the clay minerals during incubation and after H 2 O 2 treatment provided evidence for surface adsorption by vermiculite and pore entrapment by kaolinite and illite assemblages. The SOM protection extent parameter, defined based on accumulative soil respiration dynamics, explained well the variation of the formation efficiency of mineral associated SOM (MAOM) and, to a lesser extent, that of occluded particulate SOM (oPOM) in aggregates. 90–96% of plant litter-derived C was protected in the vermiculite material and 33–60% in the pure kaolinite and illite materials. The pure vermiculite material showed the greatest fractions of MAOM and oPOM, the highest relative abundances of O–alkyls and anomeric from carbohydrates in the MAOM fraction. < 1% of plant litter-derived C was transformed into microbial biomass and residues, and fungal residues only were associated with the pure vermiculite material. These results suggested that plant litter incorporated into the soil was decomposed mainly through the ex vivo modification pathway and transformed into SOM through both mineral-organic association and physical protection pathways. Plant litter-derived C was likely protected through mineral-organic association from the earlier stages of decomposition by vermiculite than kaolinite and illite, resulting in more plant carbohydrates associated with vermiculite. Therefore, clay minerals determined SOM formation pathways and played a greater role in controlling SOM formation efficiency than plant litter quality. [ABSTRACT FROM AUTHOR]

Soil microbial biomass is key to improving the prediction of soil organic carbon (SOC) dynamics by modeling. However, the driving mechanism of microbial biomass of different groups with soil depth is poorly understood across sites. Here, we compiled the biomass of different microbial groups (i.e., fungi, bacteria, gram-positive bacteria G+, and gram-negative bacteria G-) from the surface to a soil depth of 1 m from 71 soil profiles across three continents. We found that the biomass of microbial groups all decreased with soil depth but at different magnitudes, while the relative abundance of microbial groups, except G-, was relatively stable along soil profiles. Soil fungal biomass had a shallower vertical distribution than bacteria, especially G+, with 89% fungi and 76% G+ in the top 10 cm soils. In addition, a greater proportion of microbial biomass (71–89%) compared to SOC (64%) was in the top 10 cm soils, suggesting that microbes and SOC exhibited different vertical distributions. The vertical distributions of microbial biomass of different groups were significantly correlated with SOC and clay content but not with climate, and these distributions were different among land uses, highlighting the great influences of edaphic factors on vertical distributions of microbial biomass. The relationship between microbial biomass and soil depth provides a feasible way to estimate microbial biomass at different soil depths, which can serve as a benchmark to improve the prediction of SOC dynamics of entire soil profile at large scales. [Display omitted] • Absolute biomass not relative abundance of microbes decreases with soil depth. • Fungal biomass has shallower vertical distributions than bacterial biomass. • ~80% microbial biomass and 64% soil organic C are distributed in 0–10 cm soils. • Vertical distributions of microbial biomass are regulated by substrates and clay content. [ABSTRACT FROM AUTHOR]

Rechargeable sodium-chlorine (Na-Cl 2 ) batteries show high theoretical specific energy density and excellent adaptability for extreme environmental applications. However, the reported cycle life is mostly less than 500 cycles, and the understanding of battery failure mechanisms is quite limited. In this work, we demonstrate that the substantially increased voltage polarization plays a critical role in the battery failure. Typically, the passivation on the porous cathode caused by the deposition of insulated sodium chloride (NaCl) is a crucial factor, significantly influencing the three-phase chlorine (NaCl/Na + , Cl - /Cl 2 ) conversion kinetics. Here, a self-depassivation strategy enabled by iodine anion (I - )-tuned NaCl deposition was implemented to enhance the chlorine reversibility. The nucleation and growth of NaCl crystals are well balanced through strong coordination of the NaI deposition-dissolution process, achieving depassivation on the cathode and improving the reoxidation efficiency of solid NaCl. Consequently, the resultant Na-Cl 2 battery delivers a super-long cycle life up to 2000 cycles., (© 2024. The Author(s).)

Rechargeable sodium chloride (Na-Cl 2 ) batteries have emerged as promising alternatives for next-generation energy storage due to their superior energy density and sodium abundance. However, their practical applications are hindered by the sluggish chlorine cathode kinetics related to the aggregation of NaCl and its difficult transformation into Cl 2 . Herein, the study, for the first time from the perspective of electrode level in Na-Cl 2 batteries, proposes a free-standing carbon cathode host with customized vertical channels to facilitate the SOCl 2 transport and regulate the NaCl deposition. Accordingly, electrode kinetics are significantly enhanced, and the deposited NaCl is distributed evenly across the whole electrode, avoiding the blockage of pores in the carbon host, and facilitating its oxidation to Cl 2. With this low-polarization cathode, the Na-Cl 2 batteries can deliver a practically high areal capacity approaching 4 mAh cm -2 and a long cycle life of over 170 cycles. This work demonstrates the significance of pore engineering in electrodes for mediating chlorine conversion kinetics in rechargeable alkali-metal-Cl 2 batteries., (© 2024 Wiley‐VCH GmbH.)

Introduction: The issue of tobacco control remains a significant concern for public health worldwide. In recent years, remarkable progress has been made toward adopting smoke-free measures in indoor public places. Although China has yet to introduce a national regulation, specifically for smoke-free public places, more than a dozen cities have successively approved and implemented comprehensive smoke-free regulations. Different cities in China have diverse attitudes and behaviors toward smoke-free policies; however, the reasons for these policy differences and the influencing factors have not received sufficient attention and research., Methods: On the basis of the multiple streams framework, this study selects 36 key Chinese cities as research samples and uses a directed dyad-year event history analysis method to analyze the factors influencing the implementation of comprehensive smoke-free policies in cities., Results: Results show that the adoption of such policies is positively influenced by scientific evidence, focal events, media coverage, institutional foundations, economic comparisons, and the influence of health departments and of tobacco control groups. By contrast, policy adoption is negatively affected by the differences in administrative levels, central policy signals, and the influence of the tobacco industry., Discussion: This study contributes to understanding the internal logic behind local governments' adoption of comprehensive smoke-free policies, offering insights for further advocacy at the city and national levels in China and providing experiences that can promote the global tobacco control movement., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Feng, Qin, Jin and Li.)

Soil organic carbon (SOC), as a crucial measure of soil quality, is typically low in arid regions due to salinization, which is a global issue. How soil organic carbon changes with salinization is not a simple concept, as high salinity simultaneously affects plant inputs and microbial decomposition, which exert opposite effects on SOC accumulation. Meanwhile, salinization could affect SOC by altering soil Ca 2+ (a salt component), which stabilizes organic matter via cation bridging, but this process is often overlooked. Here, we aimed to explore i) how soil organic carbon changes with salinization induced by saline-water irrigation and ii) which process drives soil organic carbon content with salinization, plant inputs, microbial decomposition, or soil Ca 2+ level. To this end, we assessed SOC content, plant inputs represented by aboveground biomass, microbial decomposition revealed by extracellular enzyme activity, and soil Ca 2+ along a salinity gradient (0.60-31.09 g kg -1 ) in the Taklamakan Desert. We found that, in contrast to our prediction, SOC in the topsoil (0-20 cm) increased with soil salinity, but it did not change with the aboveground biomass of the dominant species (Haloxylon ammodendron) or the activity of three carbon-cycling relevant enzymes (β-glucosidase, cellulosidase, and N-acetyl-beta-glucosaminidase) along the salinity gradient. Instead, SOC changed positively with soil exchangeable Ca 2+ , which increased linearly with salinity. These results suggest that soil organic carbon accumulation could be driven by increases in soil exchangeable Ca 2+ under salinization in salt-adapted ecosystems. Our study provides empirical evidence for the beneficial impact of soil Ca 2+ on organic carbon accumulation in the field under salinization, which is apparent and should not be disregarded. In addition, the management of soil carbon sequestration in salt-affected areas should be taken into account by adjusting the soil exchangeable Ca 2+ level., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Designing Pt-based electrocatalysts with high catalytic activity and CO tolerance is challenging but extremely desirable for alkaline hydrogen oxidation reaction. Herein we report the design of a series of single-atom lanthanide (La, Ce, Pr, Nd, and Lu)-embedded ultrasmall Pt nanoclusters for efficient alkaline hydrogen electro-oxidation catalysis based on vapor filling and spatially confined reduction/growth of metal species. Mechanism studies reveal that oxophilic single-atom lanthanide species in Pt nanoclusters can serve as the Lewis acid site for selective OH - adsorption and regulate the binding strength of intermediates on Pt sites, which promotes the kinetics of hydrogen oxidation and CO oxidation by accelerating the combination of OH - and *H/*CO in kinetics and thermodynamics, endowing the electrocatalyst with up to 14.3-times higher mass activity than commercial Pt/C and enhanced CO tolerance. This work may shed light on the design of metal nanocluster-based electrocatalysts for energy conversion., (© 2023. The Author(s).)

Soil is the largest terrestrial reservoir of organic carbon and is central for climate change mitigation and carbon-climate feedbacks. Chemical and physical associations of soil carbon with minerals play a critical role in carbon storage, but the amount and global capacity for storage in this form remain unquantified. Here, we produce spatially-resolved global estimates of mineral-associated organic carbon stocks and carbon-storage capacity by analyzing 1144 globally-distributed soil profiles. We show that current stocks total 899 Pg C to a depth of 1 m in non-permafrost mineral soils. Although this constitutes 66% and 70% of soil carbon in surface and deeper layers, respectively, it is only 42% and 21% of the mineralogical capacity. Regions under agricultural management and deeper soil layers show the largest undersaturation of mineral-associated carbon. Critically, the degree of undersaturation indicates sequestration efficiency over years to decades. We show that, across 103 carbon-accrual measurements spanning management interventions globally, soils furthest from their mineralogical capacity are more effective at accruing carbon; sequestration rates average 3-times higher in soils at one tenth of their capacity compared to soils at one half of their capacity. Our findings provide insights into the world's soils, their capacity to store carbon, and priority regions and actions for soil carbon management., (© 2022. The Author(s).)

The electrode materials of potassium ion storage system have attracted considerable attention given the promising prospect of a potassium ion system in large-scale electrochemical energy storage applications. Despite the excellent anode performance of metal oxides in Li + and Na + batteries, the study on their K + storage performance is still rarely reported. In this study, we report a safe and low-cost strategy to prepare FeO x /N-doped carbons by using NaHCO 3 and Fe nanopowder. Benefiting from the oxidation of Fe to Fe 3 O 4 , an interesting "one stone, two birds" role of the Fe powder can be identified in the heating process. As a reduction agent, the Fe powder can consume the excess oxygen in the bio-massed carbon framework, facilitating the formation of short-range-ordered domains in the biomass-derived carbon materials (FeO x @GBHCs). Moreover, the close combination of oxidization products (Fe 3 O 4 particles) and carbon matrix leads to numerous FeO x clusters grafted on the surface of the carbon framework via the strong C-O-Fe binding. Therefore, the resultant FeO x /porous carbon exhibits a high reversible capacity of 410 mA h g -1 and an excellent cycling capability. The assembled FeO x @GBHCs//AC potassium-ion hybrid supercapacitor delivers a high energy density of 133 W h kg -1 at a power density of 700 W kg -1 , demonstrating a potential prospect of metal oxides in boosting the potassium ion storage performance.

The design of electrodes with simultaneously high compaction density, developed porosity, and structural stability has always been a challenge so as to meet the demand of high volumetric performance lithium ion storage devices. In this paper, we demonstrate a new compositing method for hollow carbon "room" loading of Fe 3 O 4 nanoparticles (HCR@Fe 3 O 4 ) with the assistance of Na 2 CO 3 salt crystal templates. The as-obtained HCR@Fe 3 O 4 composites have a massive compaction density (1.79 g cm -3 ), abundant multimodal pores (1.26 cm 3 g -1 ), and a large content of Fe 3 O 4 (64.2 wt%), which leads to excellent volumetric capacitive performance. More importantly, the unique compositing model not only provides a fast transmission channel for Li + but also alleviates the mechanical strain efficiently through the cavity between the Fe 3 O 4 nanoparticles and the carbon wall. When evaluated as an anode of lithium ion batteries, the resultant HCR@Fe 3 O 4 electrode exhibits a remarkable volumetric capacity of 2044 mA h cm -3 at 0.2 A g -1 and a stable cycle life of 828 mA h cm -3 after 1000 cycles at 5 A g -1 . The assembled HCR@Fe 3 O 4 //AC lithium ion hybrid capacitor device exhibits a high energy density of 173 W h L -1 at a power density of 190 W L -1 , demonstrating its high-level integrated volumetric density/power density.

The susceptibility of soil organic carbon (SOC) in tundra to microbial decomposition under warmer climate scenarios potentially threatens a massive positive feedback to climate change, but the underlying mechanisms of stable SOC decomposition remain elusive. Herein, Alaskan tundra soils from three depths (a fibric O horizon with litter and course roots, an O horizon with decomposing litter and roots, and a mineral-organic mix, laying just above the permafrost) were incubated. Resulting respiration data were assimilated into a 3-pool model to derive decomposition kinetic parameters for fast, slow, and passive SOC pools. Bacterial, archaeal, and fungal taxa and microbial functional genes were profiled throughout the 3-year incubation. Correlation analyses and a Random Forest approach revealed associations between model parameters and microbial community profiles, taxa, and traits. There were more associations between the microbial community data and the SOC decomposition parameters of slow and passive SOC pools than those of the fast SOC pool. Also, microbial community profiles were better predictors of model parameters in deeper soils, which had higher mineral contents and relatively greater quantities of old SOC than in surface soils. Overall, our analyses revealed the functional potential of microbial communities to decompose tundra SOC through a suite of specialized genes and taxa. These results portray divergent strategies by which microbial communities access SOC pools across varying depths, lending mechanistic insights into the vulnerability of what is considered stable SOC in tundra regions.

Bioinspired mineralization is a powerful method for designing and preparing nanomaterials. In this work, we developed a bioinspired mineralization approach under freezing conditions and fabricated methyl cellulose (MC)/NaHCO 3 flake precursors with a sophisticated hierarchical structure. Based on this, amazing wing-like porous carbon sheets (WPCSs) assembled by numerous interconnected hollow carbon bubbles were obtained after carbonization and removal of inorganic crystals, which are seldom obtained by other artificial methods. Benefiting from their open framework, large surface area, and enlarged interlayer spacing of graphitized nanocrystallites, the obtained WPCSs exhibited an obvious boost in potassium storage performance. As an anode of potassium-ion batteries, they showed high reversible capacities of 347 mAh g -1 at 50 mA g -1 and 122 mAh g -1 at 20 A g -1 and relatively stable cyclability for 3000 cycles. The assembled WPCS//WPCS potassium-ion hybrid supercapacitor delivered a high energy density of 108 Wh kg -1 at a power density of 280 W kg -1 . Given the cost effectiveness and green process, the modified bioinspired mineralization under freezing conditions would provide a facile and green way for exploring porous carbons with controlled structures and rich multifunction.

Objectives: Experimental studies suggested that bisphenol A (BPA) exposure increased the risk of metabolic syndrome (MetS) through the mechanism of insulin resistance. All previous epidemiological studies of BPA and MetS were cross-sectional studies, and their findings were mixed. This study aims to provide further evidence on the association between urinary BPA and risk of MetS using a prospective cohort study in China., Methods: The study population was from the Shenzhen Night shift workers' cohort. A total of 1227 male workers were recruited from the baseline survey in 2013 and then followed until 2017. Modified Adult Treatment Panel III criteria were used to identify the cases of MetS. Urinary BPA concentration was assessed using high-performance liquid chromatography-tandem mass spectrometry, and it was categorised into three subgroups by tertiles to obtain the adjusted HR (aHR) and 95% CI using Cox proportional hazard model., Results: During 4 years of follow-up, 200 subjects developed MetS. Compared with the lowest urinary BPA subgroup, a weakly increased risk of MetS was suggested among those with the middle (aHR=1.19, 95% CI 0.87 to 1.63) and high level of urinary BPA (aHR=1.16, 95% CI 0.84 to 1.59); however, the significant association with MetS was restricted primarily to the smokers, showing a positive gradient with urinary BPA (middle level: aHR=2.40, 95% CI 1.13 to 5.08; high level: aHR=2.87, 95% CI 1.38 to 5.98; p trend= 0.010 )., Conclusion: This prospective cohort study provided further evidence that exposure to BPA may increase the risk of MetS, and this association was further positively modified by cigarette smoking., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Quantifying soil organic carbon (SOC) decomposition under warming is critical to predict carbon-climate feedbacks. According to the substrate regulating principle, SOC decomposition would decrease as labile SOC declines under field warming, but observations of SOC decomposition under warming do not always support this prediction. This discrepancy could result from varying changes in SOC components and soil microbial communities under warming. This study aimed to determine the decomposition of SOC components with different turnover times after subjected to long-term field warming and/or root exclusion to limit C input, and to test whether SOC decomposition is driven by substrate lability under warming. Taking advantage of a 12-year field warming experiment in a prairie, we assessed the decomposition of SOC components by incubating soils from control and warmed plots, with and without root exclusion for 3 years. We assayed SOC decomposition from these incubations by combining inverse modeling and microbial functional genes during decomposition with a metagenomic technique (GeoChip). The decomposition of SOC components with turnover times of years and decades, which contributed to 95% of total cumulative CO 2 respiration, was greater in soils from warmed plots. But the decomposition of labile SOC was similar in warmed plots compared to the control. The diversity of C-degradation microbial genes generally declined with time during the incubation in all treatments, suggesting shifts of microbial functional groups as substrate composition was changing. Compared to the control, soils from warmed plots showed significant increase in the signal intensities of microbial genes involved in degrading complex organic compounds, implying enhanced potential abilities of microbial catabolism. These are likely responsible for accelerated decomposition of SOC components with slow turnover rates. Overall, the shifted microbial community induced by long-term warming accelerates the decomposition of SOC components with slow turnover rates and thus amplify the positive feedback to climate change., (© 2017 John Wiley & Sons Ltd.)