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This paper constructs an embodied carbon model in inter-provincial trade based on China’s inter-provincial multi-regional input-output table. By analyzing the embodied carbon emissions for Guangdong with the forefront of economic development, this research reveals the impact of trade scale and structure between Guangdong Province and other provinces on embodied carbon emissions, and finds out key provinces and sectors for emission reduction. It can enable national and regional economic and environmental policies to be implemented into specific industries, guide capital flow to key sectors for emission reduction, provide comments for relevant national and provincial decision-making sectors to adjust trade structure, and play the role of inter-provincial trade in energy conservation and emission reduction.

Enterprises are at the forefront of climate actions and multinational enterprises (MNEs) engage in foreign direct investment, allowing them substantial influence over the entire supply chain. Yet emissions embodied in the international supply chains of MNEs are poorly known. Here we trace the carbon footprints of foreign affiliates of MNEs and show that the gross volume of global carbon transfer through investment peaked in 2011, mainly driven by the decline in carbon intensity. Despite declining carbon footprints of developed country-based MNEs, there has been a notable increase in carbon transfer sourced from the Chinese mainland. We propose an investment-based accounting framework to allocate carbon footprints of MNEs to the investing country. Investment-based accounting of emissions could inform targeted and effective climate policies and actions. For instance, some large MNEs play a crucial role in carbon transfer, therefore their originating country should bear more responsibilities of carbon emission reduction as an investor. Multinational enterprises and their international supply chains can have large carbon footprints, but there is mitigation potential. Global carbon transfer through investment has declined in recent years, and this framework, assigning emissions to the investing country, would inform further action.

Since China carries an increasingly significant responsibility in carbon emission reduction, a systematic assessment from the multi-scale and multi-regional perspective is essential to examine the region-specific carbon emissions and different kinds of carbon transfer patterns. By identifying carbon emission flows among 31 domestic provincial administrative regions and 184 foreign countries/economies, this work examines the domestic and foreign carbon emission flows of Chinese provinces/municipalities based on the intra- and inter-national relations. Overall, the provinces and municipalities in China are divided into 4 patterns according to carbon emission flows, among which inland provinces mainly engage in domestic carbon emission transfers, western regions generally receive carbon emissions with main carbon outflows in northeastern and central provinces, and coastal regions play an essential role in balancing carbon emission surpluses and deficits between domestic and foreign regions. For different sub-regions in China, recognizing carbon emission transfer relations contributes to the synergetic and sustainable regional development from a tele-connected perspective. With the nested network analysis, the multi-scale and multi-regional assessments focusing upon China’s provinces and municipalities extend the existing research to both national and global scales, providing a solid foundation for sustainable regional development in China.

The atmosphere–land–water connectivity of dissolved organic carbon (DOC) is not altogether accounted in major rivers of India despite recent researches highlighting its importance. We studied the coupled effect of atmospheric deposition (AD) and local land use on DOC buildup in Ganga River for a period of 6 years. The AD-OC input increased consistently over time and there was over 1.5- to 1.8-fold increase in 2012 relative to 2007. Microbial activity and water soluble organic carbon (WSOC) in sub-catchment and DOC in land surface runoff increased consistently over time along the gradient of AD input. The river DOC showed positive correlation (R 2 = 0.24–0.84; p

Time dependent carbon transfer coefficients are estimated using ecosystem exchange data by minimizing over variable observational intervals, Kalman filter, and variational minimization techniques. Transfer coefficients are determined by application of estimation procedures to subintervals from a partition of the observational time period, minimizing the variance of analyzed errors without the imposition of a priori transfer coefficient models in Kalman filters, and minimization with respect to transfer coefficients in variational fit-to-data functionals. Results are compared between methods and seasonal variability is observed in the transfer coefficients.

Inborn errors of the single-carbon transfer pathway are rare disorders of folate and cobalamin metabolism. They may be complicated by demyelination resembling subacute combined degeneration of the cord and brain. The study of CSF metabolites in children with serial errors affecting the single-carbon transfer pathway has suggested that S-adenosylmethionine deficiency is a cause of the demyelination. This deficiency is corrected by treatment that causes clinical improvement and remyelination. Some treatments can only have an indirect effect on the brain and this is discussed with other evidence that the liver may produce factors that are necessary for the maintenance of central myelin.

The transfer of 14C from Lolium perenne (the donor) to Plantago lanceolata (the receiver), mediated by vesicular-arbuscular (VA) mycorrhizal fungi, was examined when the two species were grown together or separately. The VA mycorrhizal infection led to a significant increase, relative to that in uninfected plants, in the 14C transferred from donor to receiver plants, not only when the roots of the two plants were growing in intimate mixture, but also when they were separated by a root-free zone of 2.33 cm. The majority of isotope transfer between the two plant species was along the direct pathway via VA mycelium.

Lathyrus sylvestris is a pioneer legume often found in disturbed habitats. Mainly reproduced through vegetative propagation, this clonal species presents a system of ramets that remain connected for several years. The existence of carbon transfer among ramets within a clone has been studied using 14C in situ. Assimilate translocation from primary to secondary ramets was observed in all clones when the primary ramet was exposed to 14CO2. The amount of transfer ranged from trace up to 90% of the total 14C incorporated. However, in only half of the clones there was consistent enrichment of the secondary ramet (5 to 89%) suggesting that interramets transfer of carbon may be facultative. Furthermore, when significant export occurred from the primary ramet, it was always principally towards only one ramet even when the clone included more than one. The transfer of 14C from secondary to primary ramets was shown to be significant only when photosynthesis of the latter was decreased by shading. In this case import of carbon was never more than 60% of the incorporated 14C.

Studies using 1010 steel shimstock in a controlled atmosphere tubular furnace have allowed rate constants to be determined for a number of important carburizing and decarburizing reactions. Carburizing data obtained in a small commercial furnace confirm that the combination of CO and H2 to form C and H2O is the major carbon transfer reaction to the parts in a typical furnace system. The hydrocarbon injected in the furnace for enrichment deposits carbon on the heating surfaces initially as a result of catalytic cracking reactions. Due to the temperature differential between heating surfaces and parts, the CO-H2 reaction acts as a “carbon pump” in transferring this carbon to the reactive surface of the parts to be carburized. Carbon control by monitoring the concentration of CO and CO2 or CO, H2, and H2O is most efficient in the later stages of a typical furnace cycle as the carbon concentration at the surface of the parts approaches the carbon potential in the gas phase.

Carbon-isotope ratios were examined as δ(13)C values in several C3, C4, and C3-C4 Flaveria species, and compared to predicted δ(13)C, values generated from theoretical models. The measured δ(13)C values were within 4‰ of those predicted from the models. The models were used to identify factors that contribute to C3-like δ(13)C values in C3-C4 species that exhibit considerable C4-cycle activity. Two of the factors contributing to C3-like δ(13)C values are high CO2 leakiness from the C4 pathway and pi/pa values that were higher than C4 congeners. A marked break occurred in the relationship between the percentage of atmospheric CO2 assimilated through the C4 cycle and the δ(13)C value. Below 50% C4-cycle assimialtion there was no significant relationship between the variables, but above 50% the δ(13)C values became less negative. These results demonstrate that the level of C4-cycle expression can increase from, 0 to 50% with little integration of carbon transfer from the C4 to the C3 cycle. As expression increaces above 50%, however, increased integration of C3- and C4-cycle co-function occurs.

Methods for labelling growing plants by exposing them to C14O2 under a cellulose acetate-butyrate canopy have been developed for laboratory and field use. The length of labelling ranged from 2 to 33 days and the C14O2 content of the atmosphere was automatically controlled. This made it possible to measure carbon assimilation by the plants, transfer of photosynthates beneath ground and respiration of the roots.