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In response to a strong El Niño, fires in Indonesia during September and October 2015 released a large amount of carbon dioxide and created a massive regional smoke cloud that severely degraded air quality in many urban centers across Southeast Asia. Although several lines of evidence indicate that peat burning was a dominant contributor to emissions in the region, El Niño-induced drought is also known to increase deforestation fires and agricultural waste burning in plantations. As a result, uncertainties remain with respect to partitioning emissions among different ecosystem and fire types. Here we measured the radiocarbon content (14C) of carbonaceous aerosol samples collected in Singapore from September 2014 through October 2015, with the aim of identifying the age and origin of fire-emitted fine particulate matter (particulate matter with an aerodynamic diameter less than or equal to 2.5 μm). The Δ14C of fire-emitted aerosol was -76 ± 51‰, corresponding to a carbon pool of combusted organic matter with a mean turnover time of 800 ± 420 y. Our observations indicated that smoke plumes reaching Singapore originated primarily from peat burning (∼85%), and not from deforestation fires or waste burning. Atmospheric transport modeling confirmed that fires in Sumatra and Borneo were dominant contributors to elevated PM2.5 in Singapore during the fire season. The mean age of the carbonaceous aerosol, which predates the Industrial Revolution, highlights the importance of improving peatland fire management during future El Niño events for meeting climate mitigation and air quality commitments.

In order to realistically fulfil global and national climate protection targets, all potential measures have to be made use of to a maximum extent. Because it is readily available, biomass energy has been playing a key practical role for decades, supported by the traditional assumption of its carbon neutrality: under sustainable conditions, carbon dioxide emitted during combustion is held to be equal to its absorption during plant growth. In order to clarify conditions of carbon (C) neutrality, it is therefore necessary to model the annual natural C cycle on the entire planet and to include changes caused by a variety of growth strategies for biomass fuels. The "Combined Energy and Biosphere Model" CEBM calculates the cycle of plant growth, decay, biomass fuel production and its combustion on 2433 grid elements worldwide. CEBM results suggest that over many decades, the C pools of litter and especially soil organic carbon (i.e., humus layer) deplete considerably as a consequence of the interrupted natural carbon cycle. Overall, based on this finding, the earlier assumption of "carbon-neutral biomass fuels" is disapproved of in a long-term evaluation and—as a coarse rule of thumb—might be reduced to "half as carbon neutral as previously assumed" (when compared to a current fuel mix). On top of this principal effect, it is well known that life-cycle emissions, indirect or secondary emissions such as energy input related to production, transport and conversion into fuels will still add to this already principally highly incomplete carbon neutrality of biomass. [ABSTRACT FROM AUTHOR]

The degree to which elevated CO2 concentrations (e[CO2]) increase the amount of carbon (C) assimilated by vegetation plays a key role in climate change. However, due to the short‐term nature of CO2 enrichment experiments and the lack of reconciliation between different ecological scales, the effect of e[CO2] on plant biomass stocks remains a major uncertainty in future climate projections. Here, we review the effect of e[CO2] on plant biomass across multiple levels of ecological organization, scaling from physiological responses to changes in population‐, community‐, ecosystem‐, and global‐scale dynamics. We find that evidence for a sustained biomass response to e[CO2] varies across ecological scales, leading to diverging conclusions about the responses of individuals, populations, communities, and ecosystems. While the distinct focus of every scale reveals new mechanisms driving biomass accumulation under e[CO2], none of them provides a full picture of all relevant processes. For example, while physiological evidence suggests a possible long‐term basis for increased biomass accumulation under e[CO2] through sustained photosynthetic stimulation, population‐scale evidence indicates that a possible e[CO2]‐induced increase in mortality rates might potentially outweigh the effect of increases in plant growth rates on biomass levels. Evidence at the global scale may indicate that e[CO2] has contributed to increased biomass cover over recent decades, but due to the difficulty to disentangle the effect of e[CO2] from a variety of climatic and land‐use‐related drivers of plant biomass stocks, it remains unclear whether nutrient limitations or other ecological mechanisms operating at finer scales will dampen the e[CO2] effect over time. By exploring these discrepancies, we identify key research gaps in our understanding of the effect of e[CO2] on plant biomass and highlight the need to integrate knowledge across scales of ecological organization so that large‐scale modeling can represent the finer‐scale mechanisms needed to constrain our understanding of future terrestrial C storage. [ABSTRACT FROM AUTHOR]

The degree to which elevated CO2 concentrations (e[CO2]) increase the amount of carbon (C) assimilated by vegetation plays a key role in climate change. However, due to the short‐term nature of CO2 enrichment experiments and the lack of reconciliation between different ecological scales, the effect of e[CO2] on plant biomass stocks remains a major uncertainty in future climate projections. Here, we review the effect of e[CO2] on plant biomass across multiple levels of ecological organization, scaling from physiological responses to changes in population‐, community‐, ecosystem‐, and global‐scale dynamics. We find that evidence for a sustained biomass response to e[CO2] varies across ecological scales, leading to diverging conclusions about the responses of individuals, populations, communities, and ecosystems. While the distinct focus of every scale reveals new mechanisms driving biomass accumulation under e[CO2], none of them provides a full picture of all relevant processes. For example, while physiological evidence suggests a possible long‐term basis for increased biomass accumulation under e[CO2] through sustained photosynthetic stimulation, population‐scale evidence indicates that a possible e[CO2]‐induced increase in mortality rates might potentially outweigh the effect of increases in plant growth rates on biomass levels. Evidence at the global scale may indicate that e[CO2] has contributed to increased biomass cover over recent decades, but due to the difficulty to disentangle the effect of e[CO2] from a variety of climatic and land‐use‐related drivers of plant biomass stocks, it remains unclear whether nutrient limitations or other ecological mechanisms operating at finer scales will dampen the e[CO2] effect over time. By exploring these discrepancies, we identify key research gaps in our understanding of the effect of e[CO2] on plant biomass and highlight the need to integrate knowledge across scales of ecological organization so that large‐scale modeling can represent the finer‐scale mechanisms needed to constrain our understanding of future terrestrial C storage. [ABSTRACT FROM AUTHOR]

Rapid Arctic environmental change affects the entire Earth system as thawing permafrost ecosystems release greenhouse gases to the atmosphere. Understanding how much permafrost carbon will be released, over what time frame, and what the relative emissions of carbon dioxide and methane will be is key for understanding the impact on global climate. In addition, the response of vegetation in a warming climate has the potential to offset at least some of the accelerating feedback to the climate from permafrost carbon. Temperature, organic carbon, and ground ice are key regulators for determining the impact of permafrost ecosystems on the global carbon cycle. Together, these encompass services of permafrost relevant to global society as well as to the people living in the region and help to determine the landscape-level response of this region to a changing climate. [ABSTRACT FROM AUTHOR]

Subterranean ventilation is a non‐diffusive transport process that provokes the abrupt transfer of CO2‐rich air (previously stored) through water‐free soil pores and cracks from the vadose zone to the atmosphere, under high‐turbulence conditions. In dryland ecosystems, whose biological carbon exchanges are poorly characterized, it can strongly determine eddy‐covariance CO2 fluxes that are used to validate remote sensing products and constrain models of gross primary productivity. Although subterranean ventilation episodes (VE) may occur in arid and semi‐arid regions, which are unsung players in the global carbon cycle, little research has focused on the role of VE CO2 emissions in land–atmosphere CO2 exchange. This study shows clear empirical evidence of globally occurring VE. To identify VE, we used in situ quality‐controlled eddy‐covariance open data of carbon fluxes and ancillary variables from 145 sites in different open land covers (grassland, cropland, shrubland, savanna, and barren) across the globe. We selected the analyzed database from the FLUXNET2015, AmeriFlux, OzFlux, and AsiaFlux networks. To standardize the analysis, we designed an algorithm to detect CO2 emissions produced by VE at all sites considered in this study. Its main requirement is the presence of considerable and non‐spurious correlation between the friction velocity (i.e., turbulence) and CO2 emissions. Of the sites analyzed, 34% exhibited the occurrence of VE. This vented CO2 emerged mainly from arid ecosystems (84%) and sites with hot and dry periods. Despite some limitations in data availability, this research demonstrates that VE‐driven CO2 emissions occur globally. Future research should seek a better understanding of its drivers and the improvement of partitioning models, to reduce uncertainties in estimated biological CO2 exchanges and infer their contribution to the global net ecosystem carbon balance. [ABSTRACT FROM AUTHOR]

Rising atmospheric concentrations of carbon dioxide (CO2) and other greenhouse gases are driving modern climate change and, therefore, are having substantial and sustained impacts on natural ecosystems and human populations. In a recent article in this journal, M. F. Hossain (2022. Water, Air, and Soil Pollution. 233:105) calculated how anthropogenic activity has perturbed the global carbon cycle, forecast future increases in atmospheric CO2 concentrations, and discussed possible health consequences from rising CO2 levels. However, Hossain’s article gave an inaccurate representation of how human actions have altered the global carbon cycle. He substantially underestimated the magnitude of anthropogenic disturbances in terms of CO2 emissions from fossil fuel combustion and land use change and also underestimated the role of land and ocean processes in removing some of the emitted CO2 from the atmosphere. At the same time, he overestimated the rate at which atmospheric CO2 levels are increasing, resulting in a highly improbable forecast for atmospheric CO2 concentrations later in this century. He also exaggerated the health impacts from exposure to those CO2 levels as being severe and deadly, when our current understanding suggests that the direct effects are uncertain but likely minor. Because each of the major components of Hossain (2022) contains substantial and fundamental flaws, I warn readers to be skeptical before incorporating its findings into their understanding of carbon cycling, climate change, and human health. [ABSTRACT FROM AUTHOR]

Since the 1950s, observations of radiocarbon (14C) in tropospheric carbon dioxide (CO2) have been conducted in both hemispheres, documenting the so-called nuclear "bomb spike" and its transfer into the oceans and the terrestrial biosphere, the two compartments permanently exchanging carbon with the atmosphere. Results from the Heidelberg global network of Δ14C-CO2 observations are revisited here with respect to the insights and quantitative constraints they provided on these carbon exchange fluxes. The recent development of global and hemispheric trends of Δ14C-CO2 are further discussed in regard to their suitability to continue providing constraints for 14C-free fossil CO2 emission changes on the global and regional scale. [ABSTRACT FROM AUTHOR]

Despite its critical role in regulating the global climate and carbon cycle, the evolution of deep Pacific circulation has not been fully deciphered during the last glacial cycle. The effect of deep Pacific hydrographic change (e.g. oxygenation and circulation) on atmospheric CO 2 variation is still uncertain. Here, we study redox-sensitive elements including V-U-Mn and benthic foraminiferal δ13C at the HYIV2015-B9 site in the southern South China Sea (SCS) to reconstruct the oxygenation and δ13C signals of water masses during the last glacial cycle. The intra-basin benthic foraminiferal δ13C gradient suggests enhanced stratification of the deep Pacific during the glacial compared to the interglacial, implying sluggish abyssal Pacific overturning. This is consistent with weak Pacific Deep Water (PDW) ventilation, as indicated by high contents of authigenic V and U, and low authigenic Mn. The inferred sluggish abyssal Pacific overturning is probably associated with less transport of Lower Circumpolar Deep Water, facilitating the expansion of respired carbon storage in the glacial deep Pacific. Meanwhile, the atmospheric CO 2 rise is closely related to active abyssal Pacific overturning since late MIS 5, particularly when considering the impact of Southern Ocean upwelling modulated by Earth's obliquity. Overall, our data indicate the critical role of abyssal Pacific overturning in the carbon cycle, revealing the potential pathway for deep carbon dioxide outgassing in the North Pacific. • Reconstruction of abyssal Pacific overturning over the past ∼90 ka. • Abyssal Pacific overturning is closely related to atmospheric CO 2. • A potential pathway of deep carbon release in the North Pacific. [ABSTRACT FROM AUTHOR]

We use a statistical emulation technique to construct synthetic ensembles of global and regional sea‐air carbon dioxide (CO2) flux from four observation‐based products over 1985–2014. Much like ensembles of Earth system models that are constructed by perturbing their initial conditions, our synthetic ensemble members exhibit different phasing of internal variability and a common externally forced signal. Our synthetic ensembles illustrate an important role for internal variability in the temporal evolution of global and regional CO2 flux and produce a wide range of possible trends over 1990–1999 and 2000–2009. We assume a specific externally forced signal and calculate the rank of the observed trends within the distribution of statistically modeled synthetic trends during these periods. Over the decade 1990–1999, three of four observation‐based products exhibit small negative trends in globally integrated sea‐air CO2 flux (i.e., enhanced ocean CO2 absorption with time) that are within one standard deviation of the mean in their respective synthetic ensembles. Over the decade 2000–2009, however, three products show large negative trends in globally integrated sea‐air CO2 flux that have a low rate of occurrence in their synthetic ensembles. The largest positive trends in global and Southern Ocean flux over 1990–1999 and the largest negative trends over 2000–2009 fall nearly two standard deviations away from the mean in their ensembles. Our approach provides a new perspective on the important role of internal variability in sea‐air CO2 flux trends, and furthers understanding of the role of internal and external processes in driving observed sea‐air CO2 flux variability. Key Points: We construct synthetic large ensembles of observed sea‐air carbon dioxide flux using a statistical emulation techniqueThe synthetic large ensembles illustrate an important role for internal variability in the temporal evolution of carbon dioxide fluxWe find a wide range of possible decadal trends in carbon dioxide flux over 1990–1999 and 2000–2009 driven by internal variability [ABSTRACT FROM AUTHOR]

The abundance and size distribution of marine particles control a range of biogeochemical and ecological processes in the ocean, including carbon sequestration. These quantities are the result of complex physical‐biological interactions that are difficult to observe, and their spatial and temporal patterns remain uncertain. Here, we present a novel analysis of particle size distributions (PSDs) from a global compilation of in situ Underwater Vision Profiler 5 (UVP5) optical measurements. Using a machine learning algorithm, we extrapolate sparse UVP5 observations to the global ocean from well‐sampled oceanographic variables. We reconstruct global maps of PSD parameters (biovolume [BV] and slope) for particles at the base of the euphotic zone. These reconstructions reveal consistent global patterns, with high chlorophyll regions generally characterized by high particle BV and flatter PSD slope, that is, a high relative abundance of large versus small particles. The resulting negative correlations between particle BV and slope further suggests synergistic effects on size‐dependent processes such as sinking particle fluxes. Our approach and estimates provide a baseline for an improved understanding of particle cycles in the ocean, and pave the way to global, three‐dimensional reconstructions of PSD and sinking particle fluxes from the growing body of UVP5 observations. Key Points: We use optical observations of marine particle size distribution to reconstruct global climatological particle biovolume (BV) and spectral slopeWe describe the importance of different biogeochemical variables on particle BV and spectral slopeSpatial and seasonal variations of BV and slope are likely to have synergistic effects on carbon export [ABSTRACT FROM AUTHOR]

Summary: The significant primary production by ammonia-oxidizing archaea (AOA) in the ocean was reported, but the carbon fixation process of AOA and its community composition along the water depth remain unclear. Here, we investigated the abundance, community composition, and potential carbon fixation of AOA in water columns of the South China Sea. Higher abundances of the amoA and accA genes of AOA were found below the euphotic zone. Similarly, higher carbon fixation potential of AOA, evaluated by the ratios of amoA to accA gene, was also observed below euphotic zone and the ratios increased with increasing water depth. The vertical niche differentiation of AOA was further evidenced, with the dominant genus shifting from Nitrosopelagicus in the epipelagic zone to uncultured genus in the meso- and bathypelagic zones. Our findings highlight the higher carbon fixation potential of AOA in deep water and the significance of AOA to the ocean carbon budget.

Changes in soil carbon (C) sequestration in grassland ecosystems have important impacts on the global C cycle. As such, it is important that researchers better understand the underlying mechanisms affecting soil C. Increasing evidence has shown that atmospheric nitrogen (N) deposition can cause dramatic changes in grassland soil C. It remains unclear whether herbivore grazing, a primary means to manage and utilize grassland resources, can regulate the effects of N deposition on soil C, and whether these effects are dependent on plant community diversity.Here, we examined the joint effects of herbivore grazing and N‐addition on soil organic C (SOC) stocks in two types of communities with low and high plant diversity respectively.Our results showed that the effects of N‐addition and its combination with herbivore grazing on grassland SOC were inconsistent in the two types of communities. In the low‐diversity community, N‐addition greatly decreased SOC stocks, while grazing significantly increased it. Additionally, the grazing‐induced increase in soil C stocks in the presence of N‐addition was so great that it completely counteracted the significant decline in SOC induced by N‐addition. However, in the high‐diversity community, we observed no effects of N‐addition on SOC and grazing increased SOC only in the absence of N‐addition and had no significant effect in the presence of N‐addition.Synthesis and applications. Our study suggests that increased N deposition can trigger a remarkable reduction in soil C sequestration in grasslands with low plant diversity, but that herbivore grazing can offset this decline, which may help to mitigate greenhouse gas emissions caused by atmospheric N deposition. As a result, we suggest that moderate herbivore grazing should be considered as an effective grassland management measure for maintaining and improving grassland soil C sequestration as the increasing global changes such as elevated atmospheric carbon dioxide, N deposition and biodiversity losses threat. [ABSTRACT FROM AUTHOR]

We present a new geo-lithological map for Central Europe (Geo-LiM). It was prepared taking into account the chemical and mineralogical composition of the outcropping rocks and paying attention in discriminating metamorphic rocks, that were classified according to the chemistry of protoliths. The map was used for estimating the atmospheric CO2 consumed by the chemical weathering of silicates and carbonates. The map is made available in vector format [Donnini et al,. 2018. A new Geo-Lithological Map (Geo-LiM) for Central Europe (Germany, France, Switzerland, Austria, Slovenia, and Northern Italy) (Version 1.2) [Data set]. Zenodo Retrieved from https://zenodo.org/record/3530257], together with the computer code used to classify the lithologies and to join original maps. As a consequence, researchers can either replicate the product, or alter the code to derive a different lithological classification of the original geological maps, following the concept of Open Science.

Soil organic carbon (SOC) is significant for soil quality and global carbon cycles. SOC was observed to be related to soil geochemistry, and soils originating from different bedrocks have different geochemical properties, but the effect of bedrock on SOC is still undefined. Soils overlying different bedrocks in Zhenxiong County and Weixin County were sampled. Specifically, soils in the mineral horizon, which are less affected by the external environment than surface soils, are focused on to reveal the effect of bedrock on SOC. Al/Ti, Fe/Ti, and Al/Fe indicate a soil–rock successive relationship. SOC contents in the mineral horizon are 0.19–2.74% (1.24% on average), and those in the surface horizon are 1.26–4.01% (2.63% on average). SOC contents in the surface and mineral horizons of the same bedrock are significantly positively correlated, implying that the bedrock is an important factor affecting SOC. SOC in the mineral horizon is related to the first transition metal ions. Significantly, positive correlations of SOC (p < 0.01) with Co, Cu, Ti, V, and Zn, and a positive correlation (p < 0.05) with Ni were observed in the mineral horizon. Organic transition metal complexation seems to play an important role in governing SOC in the mineral horizon. That is, the complexation maintains organic carbon stability, slows down its decomposition rate, and accumulates organic carbon. The Ca–SOC positive correlation in the mineral horizon exits because Ca also can complex with organic carbon. Co, Cu, and V–SOC positive correlations (p < 0.05) were also observed, but there were no significant positive correlations (p < 0.01) in the surface horizon because surface SOC had diversified sources. An SOC evolution model influenced by the bedrock was forwarded. Thus, the different soil geochemistry originating from different bedrocks should be noticed when SOC and global carbon cycles are discussed.

We explore the response of the Earth’s coupled climate and carbon system to an idealized sequential addition and removal of CO _2 to the atmosphere, following a symmetric and continuous emissions pathway, in contrast to the discontinuous emissions pathways that have largely informed our understanding of the climate response to net zero and net negative emissions to date. We find, using both an Earth system model and an ensemble of simple climate model realizations, that warming during the emissions reduction and negative emissions phases is defined by a combination of a proportionality of warming to cumulative emissions characterized by the transient climate response to emissions (TCRE), and a deviation from that proportionality that is governed by the zero emissions commitment (ZEC). About half of the ZEC is realized before reaching zero emissions, and the ZEC thus also controls the timing between peak cumulative CO _2 emissions and peak temperature, such that peak temperature may occur before peak cumulative emissions if ZEC is negative, underscoring the importance of ZEC in climate policies aimed to limit peak warming. Thus we argue that ZEC is better defined as the committed warming relative to the expected TCRE proportionality, rather than as the additional committed warming that will occur after reaching net zero CO _2 emissions. Once established, the combined TCRE and ZEC relationship holds almost to complete removal of prior cumulative CO _2 emissions. As cumulative CO _2 emissions approach zero through negative CO _2 emissions, CO _2 concentrations drop below preindustrial values, while residual long-term climate change continues, governed by multicentennial dynamical processes.

Carbon capture utilization and storage (CCUS) is an indispensable process to mitigate climate change. However, a precise and feasible CCUS layout with realistic geospatial connectivity is essential to support the prospective deployment of multisectoral plants on a national scale. This study proposed an onshore-offshore CCUS source-sink matching model, distinguished by CO 2 source-sink dataset enhancement, realistic pipeline network optimization, and onshore-offshore geospatial connectivity to accurately map China's high-resolution CCUS layout. The findings showed that China's multisectoral CCUS supply potential of coal-fired power, steel, cement, and coal chemicals was approximately 1.75, 0.77, 0.56, and 0.23 Gt/a CO 2 , respectively. A complete geospatial connectivity pattern was established by connecting 1186 multisectoral CO 2 sources with 307 onshore and 22 offshore storage sites via the shared pipeline network of 80,700 km, involving plant-level cost heterogeneity, industry competition, and CCUS cluster identification. This model can be applied to other countries or globally to enhance CCUS layout strategies., Competing Interests: The authors declare no competing interests., (© 2024 The Author(s).)

The implications of climate change and other human perturbations on the oceanic carbon cycle are still associated with large uncertainties. Global‐scale modelling studies are essential to investigate anthropogenic perturbations of oceanic carbon fluxes but, until now, they have not considered the impacts of temporal changes in riverine and atmospheric inputs of P and N on the marine net biological productivity (NPP) and air–sea CO2 exchange (FCO2). To address this, we perform a series of simulations using an enhanced version of the global ocean biogeochemistry model HAMOCC to isolate effects arising from (1) increasing atmospheric CO2 levels, (2) a changing physical climate and (3) alterations in inputs of terrigenous P and N on marine carbon cycling over the 1905–2010 period. Our simulations reveal that our first‐order approximation of increased terrigenous nutrient inputs causes an enhancement of 2.15 Pg C year−1 of the global marine NPP, a relative increase of +5% over the simulation period. This increase completely compensates the simulated NPP decrease as a result of increased upper ocean stratification of −3% in relative terms. The coastal ocean undergoes a global relative increase of 14% in NPP arising largely from increased riverine inputs, with regional increases exceeding 100%, for instance on the shelves of the Bay of Bengal. The imprint of enhanced terrigenous nutrient inputs is also simulated further offshore, inducing a 1.75 Pg C year−1 (+4%) enhancement of the NPP in the open ocean. This finding implies that the perturbation of carbon fluxes through coastal eutrophication may extend further offshore than that was previously assumed. While increased nutrient inputs are the largest driver of change for the CO2 uptake at the regional scale and enhance the global coastal ocean CO2 uptake by 0.02 Pg C year−1, they only marginally affect the FCO2 of the open ocean over our study's timeline. [ABSTRACT FROM AUTHOR]

In order to realistically fulfil global and national climate protection targets, all potential measures have to be made use of to a maximum extent. Because it is readily available, biomass energy has been playing a key practical role for decades, supported by the traditional assumption of its carbon neutrality: under sustainable conditions, carbon dioxide emitted during combustion is held to be equal to its absorption during plant growth. In order to clarify conditions of carbon (C) neutrality, it is therefore necessary to model the annual natural C cycle on the entire planet and to include changes caused by a variety of growth strategies for biomass fuels. The “Combined Energy and Biosphere Model” CEBM calculates the cycle of plant growth, decay, biomass fuel production and its combustion on 2433 grid elements worldwide. CEBM results suggest that over many decades, the C pools of litter and especially soil organic carbon (i.e., humus layer) deplete considerably as a consequence of the interrupted natural carbon cycle. Overall, based on this finding, the earlier assumption of “carbon-neutral biomass fuels” is disapproved of in a long-term evaluation and—as a coarse rule of thumb—might be reduced to “half as carbon neutral as previously assumed” (when compared to a current fuel mix). On top of this principal effect, it is well known that life-cycle emissions, indirect or secondary emissions such as energy input related to production, transport and conversion into fuels will still add to this already principally highly incomplete carbon neutrality of biomass.

Summary: The conversion of CO2 to value-added products powered with solar energy is an ideal solution to establishing a closed carbon cycle. Combining microorganisms with light-harvesting nanomaterials into photosynthetic biohybrid systems (PBSs) presents an approach to reaching this solution. Metabolic pathways precisely evolved for CO2 fixation selectively and reliably generate products. Nanomaterials harvest solar light and biocompatibly associate with microorganisms owing to similar lengths scales. Although this is a nascent field, a variety of approaches have been implemented encompassing different microorganisms and nanomaterials. To advance the field in an impactful manner, it is paramount to understand the molecular underpinnings of PBSs. In this perspective, we highlight studies inspecting charge uptake pathways and singularities in photosensitized cells. We discuss further analyses to more completely elucidate these constructs, and we focus on criteria to be met for designing photosensitizing nanomaterials. As a result, we advocate for the pairing of microorganisms with naturally occurring and highly biocompatible mineral-based semiconductor nanomaterials.

Accounting for the residual land sink (or missing carbon sink) has become a major budget focus for global carbon cycle modelers. If we are not able to account for the past and current sources and sinks, we cannot make accurate predictions about future storage of fossil fuel combustion emissions of carbon in the terrestrial biosphere. Here, we show that the autochthonous production (AP) in inland waters appears to have been strengthening in response to changes in climate and land use, as evidenced by decreasing CO2 emissions from and increasing dissolved organic carbon storage and/or organic carbon burial in inland waters during recent decades. The increasing AP may be due chiefly to increasing aquatic photosynthesis caused by global warming and intensifying human activities. We estimate that the missing carbon sink associated with the strengthening AP in inland waters may range from 0.38 to 1.8 Gt C yr-1 with large uncertainties. Our study stresses the potential role that AP may play in the further evolution of the global carbon cycle. Quantitative estimates of future freshwater AP effects on the carbon cycle may also help to guide the action needed to reduce carbon emissions, and increase carbon sinks in terrestrial aquatic ecosystems.

Internal climate variability plays an important role in the abundance and distribution of phytoplankton in the global ocean. Previous studies using large ensembles of Earth system models (ESMs) have demonstrated their utility in the study of marine phytoplankton variability. These ESM large ensembles simulate the evolution of multiple alternate realities, each with a different phasing of internal climate variability. However, ESMs may not accurately represent real world variability as recorded via satellite and in situ observations of ocean chlorophyll over the past few decades. Observational records of surface ocean chlorophyll equate to a single ensemble member in the large ensemble framework, and this can cloud the interpretation of long‐term trends: are they externally forced, caused by the phasing of internal variability, or both? Here, we use a novel statistical emulation technique to place the observational record of surface ocean chlorophyll into the large ensemble framework. Much like a large initial condition ensemble generated with an ESM, the resulting synthetic ensemble represents multiple possible evolutions of ocean chlorophyll concentration, each with a different sampling of internal climate variability. We further demonstrate the validity of our statistical approach by recreating an ESM ensemble of chlorophyll using only a single ESM ensemble member. We use the synthetic ensemble to explore the interpretation of long‐term trends in the presence of internal variability and find a wider range of possible trends in chlorophyll due to the sampling of internal variability in subpolar regions than in subtropical regions. Key Points: We statistically emulate the internal variability in the historical record of chlorophyll observationsThe resulting synthetic ensemble of observed chlorophyll is comparable to a large ensemble of an Earth system modelThe synthetic ensemble reveals a wider range of internal trends in subpolar regions than subtropical regions [ABSTRACT FROM AUTHOR]

Tropical forests fix large quantities of carbon from the atmosphere every year; however, the fate of this carbon as it travels through ecosystem compartments is poorly understood. In particular, there is a large degree of uncertainty regarding the time carbon spends in an ecosystem before it is respired and returns to the atmosphere as CO2.We estimated the fate of carbon (trajectory of photosynthetically fixed carbon through a network of compartments) and its transit time (time it takes carbon to pass through the entire ecosystem, from fixation to respiration) for an old‐growth tropical forest located in the foothills of the Andes of Colombia.We show that on average, 50% of the carbon fixed at any given time is respired in <0.5 years, and 95% is respired in <69 years. The transit time distribution shows that carbon in ecosystems is respired on a range of time‐scales that span decades, but fast metabolic processes in vegetation dominate the return of carbon to the atmosphere.Synthesis. The transit time distribution integrates multiple ecosystem processes occurring at a wide range of time‐scales. It reconciles measurements of the age of respired CO2 with estimates of mean residence time in woody biomass, and provides a new approach to interpret other ecosystem level metrics such as the ratio of net primary production to gross primary production. [ABSTRACT FROM AUTHOR]

Global vegetation photosynthesis and productivity is heterogeneous in both time and space. This study found that increasing temperature was still a positive factor for the carbon uptake of ecosystems, but not in regions with more droughts. The carbon benefits from global vegetation greening could disappear in a potentially drier and warmer planet due to soil water deficit. [Display omitted] Global vegetation photosynthesis and productivity have increased substantially since the 1980s, but this trend is heterogeneous in both time and space. Here, we categorize the secular trend in global vegetation greenness into sustained greening, sustained browning and greening-to-browning. We found that by 2016, increased global vegetation greenness had begun to level off, with the area of browning increasing in the last decade, reaching 39.0 million km2 (35.9% of the world's vegetated area). This area is larger than the area with sustained increasing growth (27.8 million km2, 26.4%); thus, 12.0% ± 3.1% (0.019 ± 0.004 NDVI a−1) of the previous earlier increase has been offset since 2010 (2010–2016, P < 0.05). Global gross primary production also leveled off, following the trend in vegetation greenness in time and space. This leveling off was caused by increasing soil water limitations due to the spatial expansion of drought, whose impact dominated over the impacts of temperature and solar radiation. This response of global gross primary production to soil water limitation was not identified by land submodels within Earth system models. Our results provide empirical evidence that global vegetation greenness and primary production are offset by water stress and suggest that as global warming continues, land submodels may overestimate the world's capacity to take up carbon with global vegetation greening. [ABSTRACT FROM AUTHOR]

Here we interpret carbon dioxide (CO2) emissions from fossil fuel burning and land use as a global stress-strain experiment. We use the idea of a Maxwell body consisting of elastic and damping (viscous) elements to reflect the overall behaviour of the atmosphere–land/ocean system in response to the continued increase of CO2 emissions between 1850 and 2015. From the standpoint of a global observer, we see that as a consequence of the increase, the CO2 concentration in the atmosphere increases (rather quickly). Concomitantly, the atmosphere warms and expands, while part of the carbon is locked away (rather slowly) in land and oceans, likewise under the influence of global warming. It is not known how reversible and how much out of sync the latter process is in relation to the former. All we know is that the slower process remembers the influence of the faster one which runs ahead. Here we ask three (nontrivial) questions: (1) Can this global-scale memory?Earth’s memory?be quantified? (2) Is Earth’s memory a buffer which is negligently exploited; and in the case that it is even a limited buffer, what is the degree of exploitation? And (3) does Earth’s memory allow its persistence (path dependency) to be quantified? To the best of our knowledge, the answers to these questions are pending. We go beyond textbook knowledge by introducing three parameters that characterise the system: delay time, memory, and persistence. The three parameters depend, ceteris paribus, solely on the system’s characteristic viscoelastic behaviour and allow deeper insights into that system. We find that since 1850, the atmosphere–land/ocean system has been trapped progressively in terms of persistence (i.e., it will become progressively more difficult to strain-relax the system), while its ability to build up memory has been reduced. The ability of a system to build up memory effectively can be understood as its ability to respond still within its natural regime; or, if the build-up of memory is limited, as a measure for system failures globally in the future. Approximately 60% of Earth’s memory had already been exploited by humankind prior to 1959. We expect system failures globally well before 2050 if the current trend in emissions is not reversed immediately and sustainably. [ABSTRACT FROM AUTHOR]

Soil carbon is an important component of the global carbon cycle and consists of organic carbon (SOC) and inorganic carbon (SIC) pools. Although SIC has been recognized as a large pool, little is known about how it has been influenced by climate change and land degradation on a decadal timescale. Here, we evaluated the magnitude of the SIC stock and detected its changes under different land cover types across the Tibetan Plateau over the past decades based on repeated SIC measurements in the 1980s and 2020s at the same sites. In the soils of the Tibetan Plateau, SIC accounts for 45% and 49% of the total (organic plus inorganic) soil carbon at depths of 0–50 cm and 0–100 cm, with estimated SIC stocks of approximately 15.6 and 20.9 Pg C, and average SIC densities of 7.2 and 9.4 kg C m−2, respectively. Partial correlation and variation partitioning analyses revealed that the spatial distribution of SIC was predominantly influenced by soil properties (soil type, texture, and pH) and climate, explaining 12.1% and 7.5% of the SIC variance, respectively. Between the 1980s and the 2020s, an overall accumulation of SIC was observed for all land cover types, with an average increase of 2.3 and 2.0 g C kg−1 for the topsoil (notably 0–20 cm) and subsoil (notably 20–50 cm), respectively. However, the response of SIC to a changing climate is more nuanced; increased precipitation may reduce SIC stock in arid areas by enhancing leaching, whereas warming temperatures may contribute to SIC accumulation in humid regions. Overall, these findings have important implications for understanding the role of SIC in the global carbon cycle under future climate change events. [Display omitted] • Decadal changes in SIC were detected based on field resampling. • Overall SIC accumulation was observed across the Tibetan Plateau over the past decades. • SIC in arid and humid areas have different responses to climate change. [ABSTRACT FROM AUTHOR]

Summary: The biological carbon pump, in which carbon fixed by photosynthesis is exported to the deep ocean through sinking, is a major process in Earth's carbon cycle. The proportion of primary production that is exported is termed the carbon export efficiency (CEE). Based on in-lab or regional scale observations, viruses were previously suggested to affect the CEE (i.e., viral “shunt” and “shuttle”). In this study, we tested associations between viral community composition and CEE measured at a global scale. A regression model based on relative abundance of viral marker genes explained 67% of the variation in CEE. Viruses with high importance in the model were predicted to infect ecologically important hosts. These results are consistent with the view that the viral shunt and shuttle functions at a large scale and further imply that viruses likely act in this process in a way dependent on their hosts and ecosystem dynamics.

Summary: Atmospheric carbon dioxide concentration ([CO2]) is increasing, which increases leaf‐scale photosynthesis and intrinsic water‐use efficiency. These direct responses have the potential to increase plant growth, vegetation biomass, and soil organic matter; transferring carbon from the atmosphere into terrestrial ecosystems (a carbon sink). A substantial global terrestrial carbon sink would slow the rate of [CO2] increase and thus climate change. However, ecosystem CO2 responses are complex or confounded by concurrent changes in multiple agents of global change and evidence for a [CO2]‐driven terrestrial carbon sink can appear contradictory. Here we synthesize theory and broad, multidisciplinary evidence for the effects of increasing [CO2] (iCO2) on the global terrestrial carbon sink. Evidence suggests a substantial increase in global photosynthesis since pre‐industrial times. Established theory, supported by experiments, indicates that iCO2 is likely responsible for about half of the increase. Global carbon budgeting, atmospheric data, and forest inventories indicate a historical carbon sink, and these apparent iCO2 responses are high in comparison to experiments and predictions from theory. Plant mortality and soil carbon iCO2 responses are highly uncertain. In conclusion, a range of evidence supports a positive terrestrial carbon sink in response to iCO2, albeit with uncertain magnitude and strong suggestion of a role for additional agents of global change. See also the Commentary on this article by Way et al., 229: 2383–2385. [ABSTRACT FROM AUTHOR]

Summary: Atmospheric carbon dioxide concentration ([CO2]) is increasing, which increases leaf‐scale photosynthesis and intrinsic water‐use efficiency. These direct responses have the potential to increase plant growth, vegetation biomass, and soil organic matter; transferring carbon from the atmosphere into terrestrial ecosystems (a carbon sink). A substantial global terrestrial carbon sink would slow the rate of [CO2] increase and thus climate change. However, ecosystem CO2 responses are complex or confounded by concurrent changes in multiple agents of global change and evidence for a [CO2]‐driven terrestrial carbon sink can appear contradictory. Here we synthesize theory and broad, multidisciplinary evidence for the effects of increasing [CO2] (iCO2) on the global terrestrial carbon sink. Evidence suggests a substantial increase in global photosynthesis since pre‐industrial times. Established theory, supported by experiments, indicates that iCO2 is likely responsible for about half of the increase. Global carbon budgeting, atmospheric data, and forest inventories indicate a historical carbon sink, and these apparent iCO2 responses are high in comparison to experiments and predictions from theory. Plant mortality and soil carbon iCO2 responses are highly uncertain. In conclusion, a range of evidence supports a positive terrestrial carbon sink in response to iCO2, albeit with uncertain magnitude and strong suggestion of a role for additional agents of global change. See also the Commentary on this article by Way et al., 229: 2383–2385. [ABSTRACT FROM AUTHOR]

The global carbon cycle connects organic matter (OM) pools in soil, freshwater, and marine ecosystems with the atmosphere, thereby regulating their size and reactivity. Due to the complexity of biogeochemical processes and historically compartmentalized disciplines, ecosystem-specific conceptualizations of OM degradation have emerged independently of developments in other ecosystems. Recent discussions regarding the relative importance of molecular composition and ecosystem properties on OM degradation have diverged in opposing directions across subdisciplines, leaving our understanding inconsistent. Ecosystem-dependent theories are problematic since properties unique to an ecosystem may change in response to anthropogenic stressors, including climate change. The next breakthrough in our understanding of OM degradation requires a shift in focus towards developing a unified theory of controls on OM across ecosystems. Conceptualizations of organic matter (OM) degradation are diverging within and among the soil, freshwater, and marine subdisciplines. There is a need to step back from conceptualizations specific to certain ecosystems to holistically understand what controls the degradation of OM, regardless of the ecosystem. Ecosystem properties are changing rapidly due to anthropogenic stressors, and we encourage the development of conceptual and earth system models to be more flexible and consider conditions that may currently seem atypical for a particular ecosystem. We emphasize that the importance of molecular composition in regulating OM degradation should not be discarded, but rather we should understand when and why it appears more or less relevant than ecosystem properties. [ABSTRACT FROM AUTHOR]

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The aviation industry's emissions have had a significant impact on global climate change. This study focuses on carbon emission trading schemes, sustainable aviation fuels (SAFs), and hydrogen energy, as vital means for the aviation industry to reduce emissions. To evaluate the climate effects of global routes under four scenarios (24 sub-scenarios) until 2100, this study proposes the Aviation-FAIR (Aviation-Finite Amplitude Impulse Response) method. The findings reveal that while CO 2 emissions and concentrations are significant, other emissions, such as N 2 O and CH 4 , have a greater effective radiative forcing (ERF) and contribute significantly to climate change. Moreover, SAFs are more effective in mitigating airline pollutant emissions than relying solely on carbon trading schemes. The effectiveness of hydrogen fuel cells may be hindered by technical limitations compared to hydrogen turbine engines. The findings of this study provide reference for the global aviation industry to adopt emission reduction measures., Competing Interests: The authors declare no competing interests., (© 2024 The Author(s).)

Methane, a greenhouse gas, plays a pivotal role in the global carbon cycle, influencing the Earth's climate. Only a limited number of microorganisms control the flux of biologically produced methane in nature, including methane-oxidizing bacteria, anaerobic methanotrophic archaea, and methanogenic archaea. Although previous studies have revealed the spatial and temporal distribution characteristics of methane-metabolizing microorganisms in local regions by using the marker genes pmoA or mcrA , their biogeographical patterns and environmental drivers remain largely unknown at a global scale. Here, we used 3419 metagenomes generated from georeferenced soil samples to examine the global patterns of methane metabolism marker gene abundances in soil, which generally represent the global distribution of methane-metabolizing microorganisms. The resulting maps revealed notable latitudinal trends in the abundances of methane-metabolizing microorganisms across global soils, with higher abundances in the sub-Arctic, sub-Antarctic, and tropical rainforest regions than in temperate regions. The variations in global abundances of methane-metabolizing microorganisms were primarily governed by vegetation cover. Our high-resolution global maps of methane-metabolizing microorganisms will provide valuable information for the prediction of biogenic methane emissions under current and future climate scenarios.

The frequent trade within and beyond the Belt and Road Initiative (BRI) has prospered the economy but has also expanded carbon emissions. Here, through a multi-regional environmental input-output analysis framework, we explore the patterns and inter-sectoral linkage of trade-embodied carbon emissions among BRI countries during 2015-2019. Then, a dynamic data envelopment analysis model considering carbon inequality as a non-discretionary input is constructed to assess the carbon emission efficiency of the identified key sector. We find that trade-embodied carbon emissions in the BRI steadily increased during 2015-2019. The manufacturing sector was identified as the key sector, exhibiting an overall efficiency of 0.6268 on average, with significant efficiency disparities. Moreover, we validate the positive role of efficiency enhancement in carbon emission mitigation, as well as the negative moderating effect of carbon inequality. Overall, this study provides optimal collaboration and initiatives to mitigate trade-embodied carbon emissions among BRI countries deeply., Competing Interests: The authors declare no competing interests., (© 2024 The Author(s).)

The vast majority of freshly produced oceanic dissolved organic carbon (DOC) is derived from marine phytoplankton, then rapidly recycled by heterotrophic microbes. A small fraction of this DOC survives long enough to be routed to the interior ocean, which houses the largest and oldest DOC reservoir. DOC reactivity depends upon its intrinsic chemical composition and extrinsic environmental conditions. Therefore, recalcitrance is an emergent property of DOC that is analytically difficult to constrain. New isotopic techniques that track the flow of carbon through individual organic molecules show promise in unveiling specific biosynthetic or degradation pathways that control the metabolic turnover of DOC and its accumulation in the deep ocean. However, a multivariate approach is required to constrain current carbon fluxes so that we may better predict how the cycling of oceanic DOC will be altered with continued climate change. Ocean warming, acidification, and oxygen depletion may upset the balance between the primary production and heterotrophic reworking of DOC, thus modifying the amount and/or composition of recalcitrant DOC. Climate change and anthropogenic activities may enhance mobilization of terrestrial DOC and/or stimulate DOC production in coastal waters, but it is unclear how this would affect the flux of DOC to the open ocean. Here, we assess current knowledge on the oceanic DOC cycle and identify research gaps that must be addressed to successfully implement its use in global scale carbon models.

Land-use and land-cover changes (LULCCs) contributed around one third to the cumulative, anthropogenic CO _2 emissions from 1850 to 2019. Despite its great importance, estimates of the net CO _2 fluxes from LULCC (E _LUC ) have high uncertainties, compared to other components of the global carbon cycle. One major source of uncertainty roots in the underlying LULCC forcing data. In this study, we implemented a new high-resolution LULCC dataset (HILDA + ) in a bookkeeping model (BLUE) and compared the results to estimates from simulations based on LUH2, which is the LULCC dataset most commonly used in global carbon cycle models. Compared to LUH2-based estimates, results based on HILDA + show lower total E _LUC (global mean difference 1960–2019: 541 TgC yr ^−1 , 65%) and large spatial and temporal differences in component fluxes (e.g. CO _2 fluxes from deforestation). In general, the congruence of component fluxes is higher in the mid-latitudes compared to tropical and subtropical regions, which is to some degree explained with the different implementations of shifting cultivation in the underlying LULCC datasets. However, little agreement is reached on the trend of the last decade between E _LUC estimates based on the two LULCC reconstructions. Globally and in many regions, E _LUC estimates based on HILDA + have decreasing trends, whereas estimates based on LUH2 indicate an increase. Furthermore, we analyzed the effect of different resolutions on E _LUC estimates. By comparing estimates from simulations at 0.01 ^∘ and 0.25 ^∘ resolution, we find that component fluxes of estimates based on the coarser resolution tend to be larger compared to estimates based on the finer resolution, both in terms of sources and sinks (global mean difference 1960–2019: 36 TgC yr ^−1 , 96%). The reason for these differences are successive transitions: these are not adequately represented at coarser resolution, which has the effect that—despite capturing the same extent of transition areas—overall less area remains pristine at the coarser resolution compared to the finer resolution.

Genes, genetics, genomics, and the roles of mushrooms and toadstools in the global carbon cycle (GCC) are reviewed here. The literature survey is a tribute to the contributions made by Hungary and Hungarian scientists to fungi and mushroom research. For this reason, the names of the fungi discussed are also given in Hungarian. Fungi – like wood eating insects – are the main decomposers (a type of consumers, syn.: heterotrophs) and consequently recycle the biomass produced by photosynthetic organisms (i.e., the producers, syn.: autotrophs). Photosynthesis is driven by the solar energy day by day (by photo-autotrophs) (i.e., primary producers of chlorophyllous plants), and primary production night by night is performed by chemo-autotroph prokaryotes. Only autotrophic organisms can produce organic materials in the Earth to supply food and feed the hetero-trophs (e.g., animals, including Human), and sapro-trophs (i.e., decomposers) including fungi and bacteria. The crucial excess oxygen from the oxygenic photosynthesis supports diverse life on Earth. Mushrooms were found to have 100-1000 times smaller genomes than plants or animals, however, enormous genome expansions e.g., of Armillarias (Eng./Hung.: honey mushrooms / tuskógombák) have indicated recently that fungi continue to expand their genome. Comparative genome analyses of Polyporales mushrooms have recently identified an ongoing transitioning from white-rot (WR) towards brown-rot (BR) life style with loss of genes encoding enzymes to decay cell wall components of plants (and woody plants, the trees) including cellulose, hemicellulases, lignin (the three together are also called lignocelluloses), and pectin. In the case of lignin, genes of ligninase enzymes, which are capable of digesting lignin only, developed only in wood-decay fungi which underscore their role in GCC. Symbiosis between fungi and green algae or cyanobacteria created a new phylum the Lichens (Mycophycophyta) in evolution. A tripartite symbiosis among achlorophyllous (i.e., parasitic) mycoheterotrophic plants ↔ mycorrhizal fungi ↔ and autotrophic green plants were re-discovered recently. Here we review the achievements of research of Di-caria true fungi (Eu-mycota) of both Asco-mycota (Eng./Hung.: Sac fungi / Tömlősgombák) and Basidio-mycota (Eng./Hung.: Club fungi / Bazidiumosgombák) with special emphasis on genes, genetics and genomic and evolutionary relationships. In brackets, the commercial mushroom names of English (Eng.) and Hungarian (Hung.) are given.

We used satellite-derived estimates of global fire emissions and a chemical transport model to estimate atmospheric nitrogen (N) fluxes from savanna and deforestation fires in tropical ecosystems. N emissions and reactive N deposition led to a net transport of N equatorward, from savannas and areas undergoing deforestation to tropical forests. Deposition of fire-emitted N in savannas was only 26% of emissions - indicating a net export from this biome. On average, net N loss from fires (the sum of emissions and deposition) was equivalent to approximately 22% of biological N fixation (BNF) in savannas (4.0 kg N ha-1 yr-1) and 38% of BNF in ecosystems at the deforestation frontier (9.3 kg N ha-1 yr-1). Net N gains from fires occurred in interior tropical forests at a rate equivalent to 3% of their BNF (0.8 kg N ha-1 yr-1). This percentage was highest for African tropical forests in the Congo Basin (15%; 3.4 kg N ha-1 yr-1) owing to equatorward transport from frequently burning savannas north and south of the basin. These results provide evidence for cross-biome atmospheric fluxes of N that may help to sustain productivity in some tropical forest ecosystems on millennial timescales. Anthropogenic fires associated with slash and burn agriculture and deforestation in the southern part of the Amazon Basin and across Southeast Asia have substantially increased N deposition in these regions in recent decades and may contribute to increased rates of carbon accumulation in secondary forests and other N-limited ecosystems. © 2010 Blackwell Publishing Ltd.

The importance of greenhouse gas inventories cannot be overstated: the process of producing inventories informs strategies that governments will use to meet emissions reduction targets. The Intergovernmental Panel on Climate Change (IPCC) leads an effort to develop and refine internationally agreed upon methodologies for calculating and reporting greenhouse gas emissions and removals. We argue that these guidelines are not equipped to handle the task of developing national greenhouse gas inventories for most countries. Inventory guidelines are vital to implementing climate action, and we highlight opportunities to improve their timeliness and accuracy. Such reforms should provide the means to better understand and advance the progress countries are making toward their Paris commitments. Now is the time to consider challenges posed by the current process to develop the guidelines, and to avail the policy community of recent major advances in quantitative and expert synthesis to overhaul the process and thereby better equip multi-national efforts to limit climate change. [ABSTRACT FROM AUTHOR]

We present a new geo-lithological map for Central Europe (Geo-LiM). It was prepared taking into account the chemical and mineralogical composition of the outcropping rocks and paying attention in discriminating metamorphic rocks, that were classified according to the chemistry of protoliths. The map was used for estimating the atmospheric CO2 consumed by the chemical weathering of silicates and carbonates. The map is made available in vector format [Donnini et al,. 2018. A new Geo-Lithological Map (Geo-LiM) for Central Europe (Germany, France, Switzerland, Austria, Slovenia, and Northern Italy) (Version 1.2) [Data set]. Zenodo Retrieved from ], together with the computer code used to classify the lithologies and to join original maps. As a consequence, researchers can either replicate the product, or alter the code to derive a different lithological classification of the original geological maps, following the concept of Open Science. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) uptake by phytoplankton can significantly reduce the partial pressure of CO2 (pCO2) in lakes and rivers, and thereby CO2 emissions. Presently, it is not known in which inland waters on Earth a significant pCO2 reduction by phytoplankton is likely. Since detailed, comparable carbon budgets are currently not available for most inland waters, we modified a proxy to assess the pCO2 reduction by phytoplankton, originally developed for boreal lakes, for application on a global scale. Using data from 61 rivers and 125 lakes distributed over five continents, we show that a significant pCO2 reduction by phytoplankton is widespread across the temperate and sub-/tropical region, but absent in the cold regions on Earth. More specifically, we found that a significant pCO2 reduction by phytoplankton might occur in 24% of the lakes in the temperate region, and 39% of the lakes in the sub-/tropical region. We also showed that such a reduction might occur in 21% of the rivers in the temperate region, and 5% of the rivers in the sub-/tropical region. Our results indicate that CO2 uptake by phytoplankton is a relevant flux in regional and global carbon budgets. This highlights the need for more accurate approaches to quantify CO2 uptake by primary producers in inland waters, particularly in the temperate and sub-/tropical region. [ABSTRACT FROM AUTHOR]