Carbon Transfer Research Articles

Research on China’s Carbon Footprint Accounting Based on a High-Precision CO2 Emission Inventory

Calculating carbon footprints can aid in clarifying the emission reduction responsibilities in various regions. Using an input–output model and the high-precision top-down carbon emission inventory provided by the China Carbon Monitoring, Verification, and Support System for Regional (CCMVS-R), carbon footprint size and transfer direction in China were estimated. From a production responsibility perspective, Shandong, Hebei, and Inner Mongolia presented the greatest carbon footprints, while the production and distribution of electric power and heat power constituted the sector with the highest carbon footprint. From a consumption responsibility perspective, Guangdong, Shandong, and Jiangsu displayed the highest carbon footprints, whereas the construction sector presented the greatest carbon footprint. From the perspective of shared responsibility, Shandong, Guangdong, and Jiangsu experienced the greatest pressure to reduce emissions, and carbon footprint reductions in the production and distribution of electric power and heat power sector are critical for mitigating climate warming. Carbon footprints were generally transferred from economically developed regions with limited natural resources to industrially developed regions with abundant natural resources, and from developed provinces to neighboring provinces. On the basis of these results, it would be helpful for the government to formulate reasonable emission reduction measures to achieve sustainable development.

Arbuscular Mycorrhizal Fungi-Mediated Carbon Sequestration: Mechanisms, Influencing Factors, and Future Directions

Arbuscular mycorrhizal fungi (AMF) are crucial in the fight against climate change as they help store carbon in the soil by forming beneficial relationships with plant roots, boosting nutrient absorption, and driving carbon captured during photosynthesis into the soil. The carbon is stored within the fungi hyphal networks and glomalin-related soil proteins, leading to its long-term stability in the environment. However, the important role of AMF in the global carbon cycle is often underrepresented in climate models. This review discusses how AMF contributes to carbon storage in the soil, focusing on processes such as nutrient cycling, soil aggregation, and interactions with soil microorganisms. It also considers the environmental and biological factors that affect AMF-mediated carbon sequestration, including soil characteristics, climatic factors, land-use practices, and AMF biodiversity. The potential benefits of using AMF to increase carbon storage are explored with a focus on the necessity to integrate AMF inoculation into sustainable land management strategies. Current research gaps, such as the AMF's impact on soil carbon levels and the molecular mechanisms of carbon transfer, are highlighted in this review. Future studies focusing on discovering new AMF strains, considering the effects of climate change on AMF functions, and producing scalable agricultural applications are required. Exploring AMF-mediated carbon sequestration could offer a significant strategy for improving ecosystem resilience and reducing the impacts of global warming.

A multifunctional organelle coordinates phagocytosis and chlorophagy in a marine eukaryote phytoplankton Scyphosphaera apsteinii.

Mixotrophy via phagocytosis can have profound consequences for the survival of marine phytoplankton and the efficiency of carbon transfer in marine systems. Little is known about the cellular mechanisms that underly nutrient acquisition via prey uptake and processing in mixotrophic phytoplankton. We used confocal microscopy, flow cytometry, and electron microscopy to assess phagocytosis and intracellular prey processing in the diploid calcifying coccolithophore Scyphosphaera apsteinii. Bioinformatic analysis was performed to develop a working model of the pathways that likely converge to regulate mixotrophic nutrition and autophagy. We found cells ingested proxy (up to 2 μm diameter) and natural (bacteria and cyanobacteria) prey particles that are processed within a single, prominent acidic vacuole detected in 80-100% of cells during exponential growth. This organelle was constitutive in cells through all growth phases to late stationary and is inherited when cells divide. Chloroplast fragments localized to this digestive organelle. A distinct, nonacidic vacuole containing polyphosphate was also identified in cells with ingested particles. We conclude a novel acidic organelle plays a multifunctional catabolic role in both mixotrophic nutrition (phagotrophy) and autophagy (chlorophagy). This discovery illustrates the dynamic nutritional strategies that marine phytoplankton, such as coccolithophores, have evolved to acquire and conserve nutrients.

Carbon transfer from land to fluvial networks in a typical karst river-reservoir system

Carbon transfer from land to fluvial networks in a typical karst river-reservoir system

A mesocosm study on carbon transfer mechanisms from deadwood to litter through fungal hyphal growth

A mesocosm study on carbon transfer mechanisms from deadwood to litter through fungal hyphal growth

Organic carbon transfer process in advanced oxidation systems for water clean-up

Organic carbon transfer process in advanced oxidation systems for water clean-up

Sediment fluxes dominate glacial–interglacial changes in ocean carbon inventory: results from factorial simulations over the past 780 000 years

Abstract. Atmospheric CO2 concentrations varied over ice age cycles due to net exchange fluxes of carbon between land, ocean, marine sediments, lithosphere, and the atmosphere. Marine sediments and polar ice cores archived indirect biogeochemical evidence of these carbon transfers, which resulted from poorly understood responses of the various carbon reservoirs to climate forcing. Modelling studies demonstrated the potential of several physical and biogeochemical processes to impact atmospheric CO2 under steady-state glacial conditions. However, it remains unclear how much these processes affected carbon cycling during transient changes of repeated glacial cycles and what role the burial and release of sedimentary organic and inorganic carbon and nutrients played. Addressing this knowledge gap, we produced a simulation ensemble with various idealised physical and biogeochemical carbon cycle forcings over the repeated glacial inceptions and terminations of the last 780 kyr with the Bern3D Earth system model of intermediate complexity, which includes dynamic marine sediments. The long simulations demonstrate that initiating transient glacial simulations with an interglacial geologic carbon cycle balance causes isotopic drifts that require several hundreds of thousands of years to overcome. These model drifts need to be considered when designing spin-up strategies for model experiments. Beyond this, our simulation ensemble allows us to gain a process-based understanding of the transient carbon fluxes resulting from the forcings and the associated isotopic shifts that could serve as proxy data. We present results of the simulated Earth system dynamics in the non-equilibrium glacial cycles and a comparison with multiple proxy time series. From this we draw several conclusions. In our simulations, the forcings cause sedimentary perturbations that have large effects on marine and atmospheric carbon storage and carbon isotopes. Dissolved inorganic carbon (DIC) changes differ by a factor of up to 28 between simulations with and without interactive sediments, while CO2 changes in the atmosphere are up to 4 times larger when interactive sediments are simulated. The relationship between simulated DIC (−1800–1400 GtC) and atmospheric CO2 change (−170–190 GtC) over the last deglaciation is strongly setup-dependent, highlighting the need for considering multiple carbon reservoirs and multi-proxy analyses to more robustly quantify global carbon cycle changes during glacial cycles.

Wildfires mediate carbon transfer from land to lakes across boreal and temperate regions

Wildfires can disrupt carbon transport from land to water, but how lake carbon cycling responds to fires remains unclear. Here, we analyzed the concentration and dominance of the main carbon forms in total carbon pools in 54 lakes (34 burned, 20 control) across 3 regions of Quebec, Canada and Minnesota, USA from recent wildfires ( < 1 – 3 years). Lakes in burned watersheds had up to double the dissolved organic carbon concentrations of control lakes, and the fire effect was most apparent when accounting for climate and landscape drivers (e.g., catchment to lake area ratio) of lake carbon cycling. The greater quantity and dominance of dissolved organic carbon in burned lakes over other carbon forms with different turnover rates and fates suggest a potential fire-mediated carbon export up to several years post fire with a yet undetermined fate in northern forested watersheds and with important implications for regional to global carbon budgets.

Impact Factors and Structural Pathways of Carbon Emissions in the Power Sector of the Beijing–Tianjin–Hebei Region Using MRIO Analysis

The accelerated growth of the global economy has given rise to a multitude of environmental concerns that demand immediate attention. At this juncture, the total global carbon emissions are exhibiting a gradual increase. China, the United States, India, Russia, and Japan represent the top five countries in terms of global carbon emissions, collectively accounting for approximately 60% of the global total. Of these, China’s carbon emissions are the highest in the world, representing over 30% of the global total. As urbanization accelerates, the carbon emissions from urban agglomerations constitute a substantial share of the nation’s total emissions, rendering the carbon emissions of urban clusters a critical issue. In the context of China’s urban agglomerations, the Beijing–Tianjin–Hebei region, due to factors such as industrial structure, accounts for a relatively high proportion of carbon emissions, approximately 11% of the national total. The future trajectory of carbon emissions in the Beijing–Tianjin–Hebei region will significantly impact the high-quality development of the entire urban cluster. Consequently, research on carbon emissions in the Beijing–Tianjin–Hebei region is of vital importance. This paper takes the carbon emissions of the power industry in the Beijing–Tianjin–Hebei region as the research subject, analyzes its carbon emissions status, and builds a multi-regional input–output model for the Beijing–Tianjin–Hebei region based on the input–output tables and carbon emissions data of each province. This study explores the key influencing factors of carbon emissions from the power industry in this region from 2012 to 2017 and analyzes the carbon emissions transfer and structural evolution from the perspective of the region and the industry to clarify the carbon reduction responsibilities of the Beijing–Tianjin–Hebei region and provide references and recommendations for the formulation of regional collaborative emission reduction policies. The results show that the direct carbon emissions from the power industry in the Beijing–Tianjin–Hebei region account for a higher proportion compared to the indirect carbon emissions it generates by driving other industries. Industries with relatively high indirect carbon emissions in the key path include coal mining and selection, equipment manufacturing, transportation, services, etc. The capital input process from Tianjin and Hebei to Beijing is accompanied by a relatively high carbon transfer. Promoting the widespread adoption of carbon emission reduction technologies will have an effective suppressive effect on carbon emissions in the Beijing–Tianjin–Hebei region, especially in Hebei; Beijing and Tianjin should pay attention to the stimulating effect of increased final demand on carbon emissions; the transfer of carbon emissions between regions and industries shows a downward trend as the power sector undergoes transformation.

Can We Constrain Geographical Variability in the Biological Carbon Pump's Transfer Efficiency From Observations?

AbstractThe biological carbon pump (BCP) transfers large amounts of carbon from the atmosphere into the ocean's interior, contributing to carbon sequestration. Studies on latitudinal variability in organic carbon transfer to depth have yielded inconsistent results, likely due to methodological differences. To address this, we compiled particulate organic carbon (POC) flux data and BCP metrics from time‐series locations across biogeographically distinct ocean regions. We integrated multiple BCP observational techniques, including diverse collection and processing protocols, capturing diverse facets of POC flux at varying spatio‐temporal resolutions. To ensure comparability, we harmonized errors and used Monte Carlo error propagation to calculate uncertainties consistently. Our analysis reveals large local uncertainties that obscure expected latitudinal variations in BCP metrics. While such variations may exist, they remain difficult to identify with current observational data. Our findings underscore the need for sustained POC flux observations, standardization of protocols, and intercalibration of technologies to identify geographic BCP patterns.

ARE THERE TIME-VARYING CAUSALITIES BETWEEN TRADE POLICY UNCERTAINTY AND CARBON EMISSION TRANSFER? NEW EVIDENCE FROM CHINA

In this paper, we examine the relationship between Chinese carbon emission transfer and trade policy uncertainty. We identify the evidence of bidirectional Granger causality using the bootstrap rolling-window approach, and further test the influence mechanism using a logit model. Empirical results spanning different sub-samples reveal a two-way causal relationship between trade policy uncertainty and carbon emission transfer. Trade policy uncertainty will reduce carbon emission transfer indirectly by limiting international trade and foreign direct investment. Whereas trade policy uncertainty will boost carbon emission transfer by increasing technological innovation hurdles. Conversely, carbon emission transfer exacerbates trade policy uncertainty through strategic environmental policies and carbon tariffs. This discovery broadens the research on trade policy uncertainty to environmental concerns, and time-varying causation expands the impact path of carbon emission transfer while clarifying global carbon emission responsibility. The findings recommend a responsible trading strategy based on environmental considerations and international cooperation to limit carbon transfer.

Transcriptomic Signature of Lipid Production in Australian Aurantiochytrium sp. TC20

Aurantiochytrium not only excels in producing long-chain polyunsaturated fatty acids such as docosahexaenoic acid for humans, but it is also a source of essential fatty acids with minimal impacts on wild fisheries and is vital in the transfer of atmospheric carbon to oceanic carbon sinks and cycles. This study aims to unveil the systems biology of lipid production in the Australian Aurantiochytrium sp. TC20 by comparing the transcriptomic profiles under optimal growth conditions with increased fatty acid production from the early (Day 1) to late exponential growth phase (Day 3). Particular attention was paid to 227 manually annotated genes involved in lipid metabolism, such as FAS (fatty acid synthetase) and subunits of polyunsaturated fatty acids (PUFA) synthase. PCA analysis showed that differentially expressed genes, related to lipid metabolism, efficiently discriminated Day 3 samples from Day 1, highlighting the key robustness of the developed lipid-biosynthesis signature. Highly significant (pFDR < 0.01) upregulation of polyunsaturated fatty acid synthase subunit B (PFAB) involved in fatty acid synthesis, lipid droplet protein (TLDP) involved in TAG-synthesis, and phosphoglycerate mutase (PGAM-2) involved in glycolysis and gluconeogenesis were observed. KEGG enrichment analysis highlighted significant enrichment of the biosynthesis of unsaturated fatty acids (pFDR < 0.01) and carbon metabolism pathways (pFDR < 0.01). This study provides a comprehensive overview of the transcriptional landscape of Australian Aurantiochytrium sp. TC20 in the process of fatty acid production.

Multi-interacting global-change drivers reduce photosynthetic and resource use efficiencies and prompt a microzooplankton-phytoplankton uncoupling in estuarine communities.

Multi-interacting global-change drivers reduce photosynthetic and resource use efficiencies and prompt a microzooplankton-phytoplankton uncoupling in estuarine communities.

Investigation of the Physical Properties of Different Ion Species at Hadron Therapy; A Comprehensive Study

Purpose: Recently, using hadrons as a therapeutic beam has been highly advised for radiation treatment of mainly deep-seated tumors due to the desired conforming of three-dimensional dose conformation onto tumor volume. This refers to the physical properties of commonly available hadrons versus photons and electrons in colliding with patient body atoms which is our main challenge in this study, in a comparative fashion. Materials and Methods: In this work, protons Caron- and Oxygen-Ions are considered as hadron beams while irradiating a given tumor located at soft tissue equivalent phantom to mimic the patient body using FLUKA simulation code. The high-impact properties of available beams implemented at hadron therapy facilities are investigated quantitatively, during the simulation process while no study has been done formerly. Results: Depth dose profiles of hadrons, linear energy transfer, beams lateral divergence, spread out Bragg peak, produced neutrons and positron emitter as radioisotopes produced due to colliding hadrons with the nucleus of the atoms are measured, numerically. The latter case include C10, C11, N13, and O15 in soft tissue which are highly important for proton range verification inside the patient body using positron emission tomography. Conclusion: The physical properties of different therapeutic ion species were compared comprehensively. Among hadrons, linear energy transfer of Carbon- and Oxygen ions is superior versus proton due to their high atomic numbers that reduce treatment sessions remarkably. Furthermore, in proton therapy, the main source of produced neutrons are passive or active modulation devices located in front of the therapeutic beam. Among produced positron emitters, C11 and O15 are remarkable for providing functional images to assess the hadron range inside the patient body.

Spatial Analysis of Carbon Metabolism in Different Economic Divisions Based on Land Use and Cover Change (LUCC) in China

Urbanization has greatly altered Earth’s surface form, and land use changes can lead to significant changes in carbon emissions. However, how these changes affect ecosystems remains unclear. Therefore, this study calculated the carbon absorption and emissions in 31 Chinese provinces using high-resolution (300 m) land use data. Subsequently, a carbon flow model was used to evaluate the carbon transfer that occurred from the changes in land use in every province between 2000 and 2020. The standard deviation ellipse analytic techniques were also employed to research the spatiotemporal evolution features of carbon flow in various economic zones. Furthermore, the flux and utility analysis approaches in ecological network analysis were used to quantitatively examine the interaction relationship between two carbon metabolism land uses. The results revealed that the continuous expansion of China’s construction land has reduced the area of agricultural land, resulting in industrial land (53.14%) and urban land (39.38%) being the main contributors to the total carbon emissions. Among them, the five eastern provinces of Hebei, Jiangsu, Zhejiang, Shandong, and Guangdong had carbon emissions of more than 100 million tons. From 2000 to 2020, the center of gravity of the carbon flow in construction land had shifted significantly from Henan Province to Gansu Province. The ecological relationship of exploitation and control dominated the two land use types. It is mostly found in Xinjiang, Qinghai, Gansu, Inner Mongolia, and Ningxia provinces. The findings could provide relevant policy implications for the Chinese government to mitigate carbon metabolism on land.

Soil Organic Carbon Estimation and Transfer Framework in Agricultural Areas Based on Spatiotemporal Constraint Strategy Combined with Active and Passive Remote Sensing

Mapping soil organic carbon (SOC) plays a crucial role in agricultural productivity and water management. This study discusses the potential of active and passive remote sensing for SOC estimation modeling in agricultural areas, incorporating synthetic aperture radar (SAR) data (L-band quad-polarization and C-band dual-polarization), multi-spectrum (MS) data, and brightness temperature (TB) data. The performance of five advanced machine learning regression (MLR) models for SOC modeling was assessed, focusing on spatial interpolation accuracy and cross-spatial transfer accuracy, using two field observation datasets for modeling and validation. Results indicate that the SOC estimation accuracy when using MS data alone is comparable to that of using TB data alone, and both perform slightly better than SAR data. Radar cross-polarization ratio index, microwave polarization difference index, shortwave infrared reflectance, and soil parameters (elevation and soil moisture) demonstrate high correlation with the measured SOC. Incorporating temporal features, as opposed to single-phase features, allows each regression model to reach its upper limit of SOC estimation accuracy. The spatial interpolation accuracy of each MLR algorithm is satisfactory, with the Gaussian process regression (GPR) model demonstrating optimal modeling performance. When SAR, MS, or TB data are used individually in modeling, the estimation errors (RMSE) for SOC are 0.637 g/kg, 0.492 g/kg, and 0.229 g/kg for the SMAPVEX12 sampling campaign, and 0.706 g/kg, 0.454 g/kg, and 0.474 g/kg for the SMAPVEX16-MB sampling campaign, respectively. After incorporating soil moisture and topographic factors, the above RMSEs for SOC are further reduced by 57.8%, 35.6%, and 3.5% for the SMAPVEX12, and by 18.4%, 8.8%, and 3.4% for the SMAPVEX16-MB, respectively. However, cross-spatial transfer accuracy of the regression models remains limited (RMSE = 0.866–1.043 g/kg and 0.995–1.679 g/kg for different data sources). To address this, this study reduces uncertainties in SOC cross-spatial transfer by introducing terrain factors sensitive to SOC (RMSE = 0.457–0.516 g/kg and 0.799–1.198 g/kg for different data sources). The proposed SOC estimation and transfer framework, based on active and passive remote sensing data, provides guidance for high-resolution regional-scale SOC mapping and applications.

Predicting the impact of dynamic global urban expansion on urban soil organic carbon

Urban expansion has triggered significant changes in soil organic carbon (SOC), profoundly affecting the global carbon cycle. The accurate prediction of the global distribution of urban SOC and assessment of the impact of future urban expansion on SOC are essential for urban soil carbon management. By using data from 377 urban locations, this study estimated the global distribution of urban SOC and projected future SOC changes under two socioeconomic scenarios: SSP126 and SSP585. The results showed that compared with the urban SOC density in 2000 (64.75 Mg C ha− 1), the global urban SOC density by 2100 decreased by 1.19% and 4.72% under the SSP126 and SSP585 scenarios, respectively. However, urban SOC stocks increased by 66.13% and 178.75% by 2100 under SSP126 and SSP585, respectively, reflecting a “carbon transfer” from natural ecosystems to urban land use. This study provides critical insights into the dynamics of urban SOC and underscores the necessity to balance urban expansion with ecosystem protection to reduce carbon loss and stabilise the global carbon balance.

Non-negligible Organic Carbon Transfer during Organic Pollutant Degradation Processes by Advanced Oxidation Technologies

Non-negligible Organic Carbon Transfer during Organic Pollutant Degradation Processes by Advanced Oxidation Technologies

Marine carbon burial enhanced by microbial carbonate formation at hydrocarbon seeps

Some of the carbon removed from Earth’s surface is stored within authigenic carbonate in marine sediments. Methane seeps are crucial sites of global marine carbon cycling sustaining microbial activity, enabling carbonate formation and the transfer of methane-derived carbon to the geosphere. Carbon sequestration rates depend on carbonate precipitation rates, which can be accelerated by mat-forming microorganisms that are ubiquitous at methane seeps and other Earth surface environments today. We investigate a 5-m-long drill core from an active methane seep at 1350 m water depth in the South China Sea with an exceptional abundance of pink and clear aragonite cement derived from the sulfate-driven anaerobic oxidation of methane, yet both cements precipitated under different conditions. Phase-specific 230Th/U-based ages, lipid biomarker compositions, and calcium isotope data suggest that pink aragonite is a product of in situ biofilm mineralization. First estimated precipitation rates of these individual cements in the seep carbonates range from 0.04 cm/ka for clear aragonite to 1.0 cm/ka for pink aragonite, suggesting an up to 25-fold increase in precipitation rates associated with biofilm mineralization. These results provide first kinetic constraints for future quantitative carbon cycle models, emphasizing the role of biofilms in accelerating carbon sequestration in marine authigenic carbonates.

Bottom-up carbon dots: purification, single-particle dynamics, and electronic structure.

The physico-chemical properties of 'bottom-up' carbon dots synthesized from small molecules feature both generalities, such as sp2-networked carbon and core-surface energy transfer, and heterogeneities, due to the unpredictable location of heteroatoms and often non-crystalline structure. Here we focus our review on three aspects of these systems: (1) coupling characterization with bottom-up synthesis to identify and remove confounding byproducts such as small molecules or hydrogen-rich polymers; (2) single-particle characterization to obtain unambiguous information on carbon dots and highlight the distribution of properties around the ensemble average; (3) electronic structure of carbon dots and how it can help elucidate the origin of important properties such as optical absorption and fluorescence from a heterogeneous ensemble of carbon dots.