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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.

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.

Since the rapid development of network technology, the rise of live-streaming shopping platforms has followed. Some streamers influence consumers’ preferences for products through their gender role attributes, thus generating great commercial value. Based on attachment theory and using an experimental approach, this study explored the impact of streamers’ gender roles (single gender/androgyny) on consumers’ preferences through 2 studies. Study 1 shows the androgynous streamer elicits a higher product preference than the single-gender (masculine and feminine) streamer. Study 2 demonstrates the moderating effect of gender stereotypes through 2 experiments to construct clear boundary conditions for the main effect and the results show that regardless of whether the streamer is male or female when individuals have a high gender stereotype, the single-gender streamer leads to a higher product preference than the androgynous streamer. When individuals have a low gender stereotype, the androgynous streamer promotes a higher product preference than the single-gender streamer.

Rechargeable sodium-chlorine (Na-Cl2) 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-/Cl2) 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-Cl2 battery delivers a super-long cycle life up to 2000 cycles. An iodine-induced self-depassivation strategy extends Na-Cl2 battery life to 2000 cycles by forming high-reactivity NaCl and lowering the chlorine conversion polarization, which successfully solves a key failure mechanism for superior reversibility. [ABSTRACT FROM AUTHOR]

A fundamental challenge in soil macroecology is to understand how microbial community structure shapes ecosystem function along environmental gradients of the land surface at broad spatial scales (i.e. the horizontal dimension). However, little is known about microbial community structure–function relationships in extreme environments along environmental gradients of soil depth at finer spatial scales (i.e. the vertical dimension). Here, we propose a general spatial dimension partitioning approach for assessing the patterns and drivers of soil microbial community structure–function relationships across horizontal and vertical spatial gradients simultaneously. We leveraged a 200‐km desert soil salinity gradient created by a 12‐year saline‐water irrigation in the Tarim basin of Taklamakan Desert. Specifically, using a general linear model, hierarchical variance partitioning, and a path model, we assessed the patterns and key ecological processes controlling spatial turnover in microbial community structure (i.e. β‐diversity) and enzymatic activity relevant to carbon, nitrogen, and phosphorus cycling along soil salinity gradients across study sites (horizontal dimension) and soil depths (vertical dimension). We found a decoupled relationship between soil microbial β‐diversity and enzymatic activity. Differences in soil depth (on the scale of meters) were as important as geographic distance (on the scale of kilometers) in shaping bacterial and fungal β‐diversity. However, the vertical and horizontal turnover in enzymatic activity was largely attributed to an increase in the heterogeneity of soil properties, such as soil texture, water content, and pH. Our findings suggest that dispersal limitation controls microbial community β‐diversity and that environmental heterogeneity, rather than soil salinization, controls enzymatic activity. Taken together, this work highlights that in the face of ongoing environmental alterations, soil depth is an under‐explored spatial dimension that must be considered in soil conservation efforts as a critical factor in determining microbial community structure and function in extreme environments. [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.

The color of green product advertisements is an important factor affecting consumers’ preferences. Based on the theory of the self-control system, this paper explores the influence mechanism and boundary conditions of green product ad color on consumers’ preferences through three experiments. Experiment 1 tested the effect of advertisement color type (green/color) on consumers’ preferences for green products. The results show that color ad can promote consumers’ preferences for green products compared with green ad. Experiment 1 also analyzed the mediating role of the self-control system between advertisement color type (green/color) and consumers’ preferences. Experiment 2 further clarified the boundary of the main effect. The effect of ad color (green/color) on consumers’ preferences was only effective in the context of green products. Experiment 3 explored the moderating effect of green product type (egoistic/altruistic) on the main effect. The results show that only when the green product type is altruistic, the ad color type (green/color) can significantly affect consumers’ preferences. This study is the first to link the ad color of green products with consumers’ preferences. The findings confirm that the use of color ad for green products can elicit higher consumers’ preferences than pure green ad, which enriches the research on the color of green product advertisements.

This study employs morality preference theory to explore how acknowledgment type (self- vs. other-focused) influences donors' subsequent donation desires. The current research consists of 3 studies. Study 1 finds that an other-focused acknowledgment letter elicits higher subsequent donation desires than a self-focused letter. Study 2 testifies to the mediating role of morality preference between the relationship of acknowledgment type and subsequent donation desires. Study 3 manipulates the moral value on “what is the morally right thing of donation” and developed a new scale to measure morality preference. Study 4 excludes the influence of language structure and tests the main effect in a real donation behavior context.

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 CO2 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.

Improving predictions of soil organic carbon (SOC) dynamics by multi-compartment models requires validation of turnover times of different SOC pools. Techniques such as laboratory incubation and isotope analysis have been adopted to estimate C turnover times, yet no studies have systematically compared these techniques and assessed the uncertainties associated with them. Here, we tested whether C turnover times of soil fractions were biased by methodology, and how this changed across soil particle sizes and ecosystems. We identified 52 studies that quantified C turnover times in different soil particles fractionated either according to aggregate size (e.g., macro- versus micro-aggregates) or according to soil texture (e.g., sand versus silt versus clay). C turnover times of these soil fractions were estimated by one of three methods: laboratory incubation (16 studies), δ13C shift due to C3–C4 vegetation change (25 studies), and 14C dating (19 studies). All methods showed that C turnover times of soil fractions generally increase with decreasing soil particle size. However, estimates of C turnover times within soil fractions differed significantly among methods, with incubation estimating the shortest turnover times and 14C the longest. The short C turnover times estimated by incubation are likely due to optimal environmental conditions for microbial decomposition existing in these studies, which is often a poor representation of field conditions. The 13C method can only be used when documenting a successive C3 versus C4 vegetation shift. C turnover times estimated by 14C were systematically higher than those estimated by 13C, especially for fine soil fractions (i.e., silt and clay). Overall, our findings highlight methodological uncertainties in estimating C turnover times of soil fractions, and correction factors should be explored to account for methodological bias when C turnover times estimated from different methods are used to parameterize soil C models.

As the pace of modern life accelerates, social exclusion occurs more and more frequently in interpersonal interactions. The type of social exclusion can lead to different psychological needs of individuals, and, thus, affects the tendency of word-of-mouth (WOM) recommendation. There are three experiments in this research. Experiment 1 explores the influence of social exclusion types on the willingness of WOM recommendation. The result shows that being rejected increases individuals' willingness to WOM recommendations while being ignored decreases individuals' willingness. Experiment 2 explores the internal psychological mechanism of the influence of social exclusion types on WOM recommendation behavior and proves the mediating role of psychological needs (affiliative-focused needs; power/provocation need). In experiment 3, the moderating effect of product attributes (scarcity/popularity) on the main effect is analyzed. This research is the first to explore the influence of social exclusion types on individuals' willingness to WOM recommendations, which enriches the research on social exclusion in the field of WOM recommendations.

With the increasingly crowded shopping environment, social crowding has become an important factor that affects consumers’ psychology and behavior. However, the impact of social crowding on consumers’ preference for green products hasn’t been focused on. Therefore, the aim of this paper is to empirically investigate the influence of social crowding on consumers’ preference for green products. With four studies, the present research examines how social crowding influences consumers’ preferences and uncovers the underlying psychological mechanism. The research shows that consumers prefer green products more under the condition of high social crowding than low, and safety needs mediate the impact of social crowding on green products preference. However, the impact of social crowding on the preference for products is only significant in green products. It also demonstrates the moderating effect of introversion-extraversion personality traits between social crowding and green products preference. For extraverted consumers, social crowding won’t affect their preference for green products, while for introverted consumers, social crowding is more likely to increase their preference for green products. This study contributes to marketing research by proposing and testing a new mechanism that underlies social crowding.

This study employs entitativity theory to explore how acknowledgment letters from various thankers (e.g., a group of beneficiaries, a charity) influence donors’ subsequent donation desires. This empirical research consists of three experiments. Study 1 reveals that an acknowledgment letter from a group of beneficiaries elicits more favorable subsequent donation desires than an acknowledgment letter from a charity. To shed light on the psychological mechanism underlying this effect, Study 2 shows that a categorical appellation can enhance the effects of an acknowledgment letter sent by a charity. Study 3 reveals that the influence of the thanker is stronger under no external pressure conditions (than under external pressure). The current study offers insightful suggestions for the management and administration of charities.

Accurate estimate of C inputs to soils is important to improve the prediction of changes in global soil organic carbon (SOC) and SOC transformations in a microbial C cycle. In cropland crop yield are well documented and can be used to estimated C inputs accurately, thus processes in SOC biochemical cycle become critical to predict changes in SOC. We modeled the time series data of SOC stock and crop yield of multiple long-term agricultural trials that represent a range of climate, soil texture and agricultural management (e.g. fertilization and rotation) in China. The soil organic carbon (SOC) model comprised physical size and density fractions, where adsorption to minerals and occlusion in soil aggregates are considered as SOC stabilization mechanisms. Physical fractions contents in the model define soil aggregation state and thus a feedback with C stabilization due to spatial restrictions for microbial attack of occluded SOC.The inverse modeling was done with Nelder-Mead optimization algorithm to estimate the reaction rates of SOC transformations in different physical fractions and carbon use efficiency as a density-dependent function or community-level regulation parameters.The current modeling study with data of long-term SOC dynamics at known SOC inputs and texture allows us to improve the model constraints for estimating biological parameters of microbial decomposition for stable and labile organic matter in physical fractions. Further modeling results may inform us on unknown details of soil biochemical processes. [ABSTRACT FROM AUTHOR]

Improving the prediction of changes in global soil organic carbon (SOC) lies in accurate estimate of C inputs to soils and SOC turnover time. Since C inputs to soils in cropland can be estimated due to well documented data of crop yields, SOC turnover rate becomes critical for accurate prediction of changes in SOC. The laboratory incubation is widely used but cannot well represent the turnover of slow soil C that accounts for the majority of total SOC, while the long-term observation of temporal changes in SOC stock offers an opportunity to estimate the turnover of slow soil C. Using the time series data of SOC stock and crop yield of multiple long-term agricultural trials that represent a range of climate, soil properties (e.g. soil pH, texture, and mineralogy), and agricultural management (e.g. fertilization and rotation) in China, we estimated SOC turnover rates and aimed to identify the primary controls of SOC changes across Chinese cropland. We used the first-order kinetic soil C model and the inverse modeling with Markov chain the Monte Carlo algorithm to estimate the turnover rates of SOC fractions and carbon use efficiency. The preliminary results show that the turnover rate of slow soil C is positively correlated with climate (i.e. mean annual temperature and precipitation) but negatively correlated with the clay content, demonstrating that the clay content is important in regulating SOC turnover rates. Further results will inform us the main controls on SOC turnover in Chinese cropland. [ABSTRACT FROM AUTHOR]

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]

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.)