{"type": "FeatureCollection", "features": [{"id": "10.1029/2022gl098700", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:17:27Z", "type": "Journal Article", "created": "2022-07-19", "title": "Drought Legacy in Sub\u2010Seasonal Vegetation State and Sensitivity to Climate Over the Northern Hemisphere", "description": "Abstract

Droughts affect ecosystems at multiple time scales, but their sub\uffe2\uff80\uff90seasonal legacy effects on vegetation activity remain unclear. Combining the satellite\uffe2\uff80\uff90based enhanced vegetation index MODIS EVI with a novel location\uffe2\uff80\uff90specific definition of the growing season, we quantify drought impacts on sub\uffe2\uff80\uff90seasonal vegetation activity and the subsequent recovery in the Northern Hemisphere. Drought legacy effects are quantified as changes in post\uffe2\uff80\uff90drought greenness and sensitivity to climate. We find that greenness losses under severe drought are partially compensated by a \uffe2\uff88\uffbc+5% greening within 2\uffe2\uff80\uff936 growing\uffe2\uff80\uff90season months following the droughts, both in woody and herbaceous vegetation but at different timings. In addition, post\uffe2\uff80\uff90drought sensitivity of herbaceous vegetation to hydrological conditions increases noticeably at high latitudes compared with the local normal conditions, regardless of the choice of drought time scales. In general, the legacy effects on sensitivity are larger in herbaceous vegetation than in woody vegetation.Microorganisms function as open systems that exchange matter and energy with their surrounding environment. Even though mass (carbon and nutrients) and energy exchanges are tightly linked, there is a lack of integrated approaches that combine these fluxes and explore how they jointly impact microbial growth. Such links are essential to predicting how the growth rate of microorganisms varies, especially when the stoichiometry of carbon- (C) and nitrogen (N)-uptake is not balanced. Here, we present a theoretical framework to quantify the microbial growth rate for conditions of C-, N-, and energy-(co-) limitations. We use this framework to show how the C:N ratio and the degree of reduction of the organic matter (OM), which is also the electron donor, availability of electron acceptors (EAs), and the different sources of N together control the microbial growth rate under C, nutrient, and energy-limited conditions. We show that the growth rate peaks at intermediate values of the degree of reduction of OM under oxic and C-limited conditions, but not under N-limited conditions. Under oxic conditions and with N-poor OM, the growth rate is higher when the inorganic N (NInorg)-source is ammonium compared to nitrate due to the additional energetic cost involved in nitrate reduction. Under anoxic conditions, when nitrate is both EA and NInorg-source, the growth rates of denitrifiers and microbes performing the dissimilatory nitrate reduction to ammonia (DNRA) are determined by both OM degree of reduction and nitrate-availability. Consistent with the data, DNRA is predicted to foster growth under extreme nitrate-limitation and with a reduced OM, whereas denitrifiers are favored as nitrate becomes more available and in the presence of oxidized OM. Furthermore, the growth rate is reduced when catabolism is coupled to low energy yielding EAs (e.g., sulfate) because of the low carbon use efficiency (CUE). However, the low CUE also decreases the nutrient demand for growth, thereby reducing N-limitation. We conclude that bioenergetics provides a useful conceptual framework for explaining growth rates under different metabolisms and multiple resource-limitations.Lakes (including reservoirs) are an important component of the global carbon (C) cycle, as acknowledged by the fifth assessment report of the IPCC. In the context of lakes, the boreal region is disproportionately important contributing to 27% of the worldwide lake area, despite representing just 14% of global land surface area. In this study, we used a statistical approach to derive a prediction equation\uffc2\uffa0for the partial pressure of CO2 (pCO2) in lakes as a function of lake area, terrestrial net primary productivity (NPP), and precipitation (r2\uffc2\uffa0=\uffc2\uffa0.56), and to create the first high\uffe2\uff80\uff90resolution, circumboreal map (0.5\uffc2\uffb0) of lake pCO2. The map of\uffc2\uffa0pCO2 was combined with lake area from the recently published GLOWABO database and three different estimates of the gas transfer velocity k to produce a resulting map of CO2 evasion (FCO2). For the boreal region, we estimate an average, lake area weighted, pCO2 of 966 (678\uffe2\uff80\uff931,325) \uffce\uffbcatm and a total\uffc2\uffa0FCO2 of 189 (74\uffe2\uff80\uff93347) Tg\uffc2\uffa0C\uffc2\uffa0year\uffe2\uff88\uff921, and evaluate the corresponding uncertainties based on Monte Carlo simulation. Our estimate of FCO2 is approximately twofold greater than previous estimates, as a result of methodological and data source differences. We use our results along with published estimates of the other C fluxes through inland waters to derive a C budget for the boreal region, and find that FCO2 from lakes is the most significant flux of the land\uffe2\uff80\uff90ocean aquatic continuum, and of a similar magnitude as emissions from forest fires. Using the model and applying it to spatially resolved projections of terrestrial NPP and precipitation while keeping everything else constant, we predict a 107% increase in boreal lake FCO2 under emission scenario RCP8.5 by 2100. Our projections are largely driven by increases in terrestrial NPP over the same period, showing the very close connection between the terrestrial and aquatic C cycle.Draining peatlands for forestry in the northern hemisphere turns their soils from carbon sinks to substantial sources of greenhouse gases (GHGs). To reverse this trend, rewetting has been proposed as a climate change mitigation strategy. We performed a literature review to assess the empirical evidence supporting the hypothesis that rewetting drained forested peatlands can turn them back into carbon sinks. We also used causal loop diagrams (CLDs) to synthesize the current knowledge of how water table management affects GHG emissions in organic soils. We found an increasing number of studies from the last decade comparing GHG emissions from rewetted, previously forested peatlands, with forested or pristine peatlands. However, comparative field studies usually report relatively short time series following rewetting experiments (e.g., 3\uffc2\uffa0years of measurements and around 10\uffc2\uffa0years after rewetting). Empirical evidence shows that rewetting leads to lower GHG emissions from soils. However, reports of carbon sinks in rewetted systems are scarce in the reviewed literature. Moreover, CH4 emissions in rewetted peatlands are commonly reported to be higher than in pristine peatlands. Long-term water table changes associated with rewetting lead to a cascade of effects in different processes regulating GHG emissions. The water table level affects litterfall quantity and quality by altering the plant community; it also affects organic matter breakdown rates, carbon and nitrogen mineralization pathways and rates, as well as gas transport mechanisms. Finally, we conceptualized three phases of restoration following the rewetting of previously drained and forested peatlands, we described the time dependent responses of soil, vegetation and GHG emissions to rewetting, concluding that while short-term gains in the GHG balance can be minimal, the long-term potential of restoring drained peatlands through rewetting remains promising.

Abstract. Riverine Fe input is the primary Fe source to the ocean. This study is focused on the distribution of Fe along the Lena River freshwater plume in the Laptev Sea using samples from a 600\u2009km long transect in front of the Lena River mouth. Separation of the particulate (>\u20090.22\u2009\u00b5m), colloidal (0.22\u2009\u00b5m\u20131\u2009kDa), and truly dissolved (\u200999\u2009% of particulate Fe and about 90\u2009% of the colloidal Fe was observed across the shelf, while the truly dissolved phase was almost constant across the Laptev Sea. Thus, the truly dissolved Fe could be an important source of bioavailable Fe for plankton in the central Arctic Ocean, together with the colloidal Fe. Fe-isotope analysis showed that the particulate phase and the sediment below the Lena River freshwater plume had negative \u03b456Fe values (relative to IRMM-14). The colloidal Fe phase showed negative \u03b456Fe values close to the river mouth (about \u22120.20\u2009\u2030) and positive \u03b456Fe values in the outermost stations (about +0.10\u2009\u2030). We suggest that the shelf zone acts as a sink for Fe particles and colloids with negative \u03b456Fe values, representing chemically reactive ferrihydrites. While the positive \u03b456Fe values of the colloidal phase within the outer Lena River freshwater plume, might represent Fe-oxyhydroxides, which remain in the water column, and will be the predominant \u03b456Fe composition in the Arctic Ocean.

", "keywords": ["particles", "QE1-996.5", "Ecology", "truly dissolved iron", "Geology", "Geokemi", "Lena River Plume", "iron isotopes", "01 natural sciences", "estuarine mixing", "6. Clean water", "Geovetenskap och relaterad milj\u00f6vetenskap", "Geochemistry", "iron particles", "Life", "colloids", "13. Climate action", "QH501-531", "Laptev Sea", "Fe isotopes", "14. Life underwater", "Earth and Related Environmental Sciences", "QH540-549.5", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://bg.copernicus.org/articles/16/1305/2019/bg-16-1305-2019.pdf"}, {"href": "https://doi.org/10.5194/bg-16-1305-2019"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Biogeosciences", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.5194/bg-16-1305-2019", "name": "item", "description": "10.5194/bg-16-1305-2019", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.5194/bg-16-1305-2019"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2018-04-26T00:00:00Z"}}, {"id": "10.5194/bg-19-4387-2022", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:21:08Z", "type": "Journal Article", "created": "2022-02-07", "title": "Consistent responses of vegetation gas exchange to elevated atmospheric CO 2 emerge from heuristic and optimization models", "description": "

Abstract. Elevated atmospheric CO2 concentration is expected to increase leaf CO2 assimilation rates, thus promoting plant growth and increasing leaf area. It also decreases stomatal conductance, allowing water savings that have been hypothesized to drive large-scale greening, in particular in arid and semiarid climates. However, the increase in leaf area could reduce the ameliorating effect of elevated CO2 concentration on soil water depletion. The net effect of elevated CO2 on leaf- and canopy-level gas exchange thus remains unclear. To address this question, a heuristic model based on the Partitioning of Equilibrium Transpiration and Assimilation (PETA) hypothesis and a model based on stomatal optimization theory are used and their outcomes compared. Predicted relative changes in leaf- and canopy-level gas exchange rates are used as a metric of responses to changes in atmospheric CO2 concentration. Both models predict reductions of leaf-level transpiration rate due to decreased stomatal conductance under elevated CO2, but negligible (PETA) or no (optimization) changes in canopy-level transpiration due to the compensatory effect of increased leaf area. Leaf- and canopy-level CO2 assimilation are predicted to increase, with an amplification of the CO2 fertilization effect at the canopy-level due to the enhanced leaf area. The expected increase in vapor pressure deficit (VPD) under warmer conditions is predicted to decrease the sensitivity of gas exchange to atmospheric CO2 concentration in both models except at growth temperatures lower than the photosynthetic thermal optimum. The consistent predictions by different models that canopy-level transpiration varies little under elevated CO2 due to combined stomatal conductance reduction and leaf area increase highlights the coordination of physiological and morphological characteristics in vegetation to maximize resource use (here water) under altered atmospheric conditions.

", "keywords": ["580", "2. Zero hunger", "0106 biological sciences", "QE1-996.5", "Ecology", "Geology", "15. Life on land", "01 natural sciences", "6. Clean water", "Geovetenskap och relaterad milj\u00f6vetenskap", "Physical Geography", "Life", "13. Climate action", "QH501-531", "Earth and Related Environmental Sciences", "QH540-549.5", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://pub.epsilon.slu.se/28959/1/manzoni-s-et-al-20220926.pdf"}, {"href": "https://bg.copernicus.org/articles/19/4387/2022/bg-19-4387-2022.pdf"}, {"href": "https://doi.org/10.5194/bg-19-4387-2022"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Biogeosciences", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.5194/bg-19-4387-2022", "name": "item", "description": "10.5194/bg-19-4387-2022", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.5194/bg-19-4387-2022"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2022-02-07T00:00:00Z"}}, {"id": "10.5194/bg-2018-181", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:21:08Z", "type": "Journal Article", "created": "2018-04-26", "title": "Distribution of Fe isotopes in particles and colloids in the salinity gradient along the Lena River plume, Laptev Sea", "description": "

Abstract. Riverine Fe input is the primary Fe source to the ocean. This study is focused on the distribution of Fe along the Lena River freshwater plume in the Laptev Sea using samples from a 600\u2009km long transect in front of the Lena River mouth. Separation of the particulate (>\u20090.22\u2009\u00b5m), colloidal (0.22\u2009\u00b5m\u20131\u2009kDa), and truly dissolved (\u200999\u2009% of particulate Fe and about 90\u2009% of the colloidal Fe was observed across the shelf, while the truly dissolved phase was almost constant across the Laptev Sea. Thus, the truly dissolved Fe could be an important source of bioavailable Fe for plankton in the central Arctic Ocean, together with the colloidal Fe. Fe-isotope analysis showed that the particulate phase and the sediment below the Lena River freshwater plume had negative \u03b456Fe values (relative to IRMM-14). The colloidal Fe phase showed negative \u03b456Fe values close to the river mouth (about \u22120.20\u2009\u2030) and positive \u03b456Fe values in the outermost stations (about +0.10\u2009\u2030). We suggest that the shelf zone acts as a sink for Fe particles and colloids with negative \u03b456Fe values, representing chemically reactive ferrihydrites. While the positive \u03b456Fe values of the colloidal phase within the outer Lena River freshwater plume, might represent Fe-oxyhydroxides, which remain in the water column, and will be the predominant \u03b456Fe composition in the Arctic Ocean.

", "keywords": ["particles", "QE1-996.5", "Ecology", "truly dissolved iron", "Geology", "Geokemi", "Lena River Plume", "iron isotopes", "01 natural sciences", "estuarine mixing", "6. Clean water", "Geovetenskap och relaterad milj\u00f6vetenskap", "Geochemistry", "iron particles", "Life", "colloids", "13. Climate action", "QH501-531", "Laptev Sea", "Fe isotopes", "14. Life underwater", "Earth and Related Environmental Sciences", "QH540-549.5", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://bg.copernicus.org/articles/16/1305/2019/bg-16-1305-2019.pdf"}, {"href": "https://doi.org/10.5194/bg-2018-181"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Biogeosciences", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.5194/bg-2018-181", "name": "item", "description": "10.5194/bg-2018-181", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.5194/bg-2018-181"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2018-04-26T00:00:00Z"}}, {"id": "10.5194/bg-2022-36", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:21:09Z", "type": "Journal Article", "created": "2022-02-07", "title": "Consistent responses of vegetation gas exchange to elevated atmospheric CO2 emerge from heuristic and optimization models", "description": "

Abstract. Elevated atmospheric CO2 concentration is expected to increase leaf CO2 assimilation rates, thus promoting plant growth and increasing leaf area. It also decreases stomatal conductance, allowing water savings that have been hypothesized to drive large-scale greening, in particular in arid and semiarid climates. However, the increase in leaf area could reduce the ameliorating effect of elevated CO2 concentration on soil water depletion. The net effect of elevated CO2 on leaf- and canopy-level gas exchange thus remains unclear. To address this question, a heuristic model based on the Partitioning of Equilibrium Transpiration and Assimilation (PETA) hypothesis and a model based on stomatal optimization theory are used and their outcomes compared. Predicted relative changes in leaf- and canopy-level gas exchange rates are used as a metric of responses to changes in atmospheric CO2 concentration. Both models predict reductions of leaf-level transpiration rate due to decreased stomatal conductance under elevated CO2, but negligible (PETA) or no (optimization) changes in canopy-level transpiration due to the compensatory effect of increased leaf area. Leaf- and canopy-level CO2 assimilation are predicted to increase, with an amplification of the CO2 fertilization effect at the canopy-level due to the enhanced leaf area. The expected increase in vapor pressure deficit (VPD) under warmer conditions is predicted to decrease the sensitivity of gas exchange to atmospheric CO2 concentration in both models except at growth temperatures lower than the photosynthetic thermal optimum. The consistent predictions by different models that canopy-level transpiration varies little under elevated CO2 due to combined stomatal conductance reduction and leaf area increase highlights the coordination of physiological and morphological characteristics in vegetation to maximize resource use (here water) under altered atmospheric conditions.

", "keywords": ["580", "2. Zero hunger", "0106 biological sciences", "QE1-996.5", "Ecology", "Geology", "15. Life on land", "01 natural sciences", "6. Clean water", "Geovetenskap och relaterad milj\u00f6vetenskap", "Physical Geography", "Life", "13. Climate action", "QH501-531", "Earth and Related Environmental Sciences", "QH540-549.5", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://pub.epsilon.slu.se/28959/1/manzoni-s-et-al-20220926.pdf"}, {"href": "https://bg.copernicus.org/articles/19/4387/2022/bg-19-4387-2022.pdf"}, {"href": "https://doi.org/10.5194/bg-2022-36"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Biogeosciences", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.5194/bg-2022-36", "name": "item", "description": "10.5194/bg-2022-36", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.5194/bg-2022-36"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2022-02-07T00:00:00Z"}}, {"id": "1805/38282", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:24:17Z", "type": "Journal Article", "created": "2022-11-07", "title": "Dryland productivity under a changing climate", "description": "Understanding dryland dynamics is essential to predict future climate trajectories. However, there remains large uncertainty on the extent to which drylands are expanding or greening, the drivers of dryland vegetation shifts, the relative importance of different hydrological processes regulating ecosystem functioning, and the role of land-use changes and climate variability in shaping ecosystem productivity. We review recent advances in the study of dryland productivity and ecosystem function and examine major outstanding debates on dryland responses to environmental changes. We highlight often-neglected uncertainties in the observation and prediction of dryland productivity and elucidate the complexity of dryland dynamics. We suggest prioritizing holistic approaches to dryland management, accounting for the increasing climatic and anthropogenic pressures and the associated uncertainties.", "keywords": ["2. Zero hunger", "0301 basic medicine", "15. Life on land", "ecosystem productivity", "01 natural sciences", "dryland management", "03 medical and health sciences", "Geovetenskap och relaterad milj\u00f6vetenskap", "13. Climate action", "Annan samh\u00e4llsvetenskap", "Earth and Related Environmental Sciences", "dryland dynamics", "future prediction trajectory", "Other Social Sciences", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://re.public.polimi.it/bitstream/11311/1231799/1/2022_NatClimChange_Wang%20et%20al.pdf"}, {"href": "https://www.nature.com/articles/s41558-022-01499-y.pdf"}, {"href": "https://doi.org/1805/38282"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Nature%20Climate%20Change", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "1805/38282", "name": "item", "description": "1805/38282", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/1805/38282"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2022-11-01T00:00:00Z"}}, {"id": "2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/273667", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:24:34Z", "type": "Journal Article", "created": "2017-09-11", "title": "CO2 evasion from boreal lakes: Revised estimate, drivers of spatial variability, and future projections", "description": "Abstract

Lakes (including reservoirs) are an important component of the global carbon (C) cycle, as acknowledged by the fifth assessment report of the IPCC. In the context of lakes, the boreal region is disproportionately important contributing to 27% of the worldwide lake area, despite representing just 14% of global land surface area. In this study, we used a statistical approach to derive a prediction equation\uffc2\uffa0for the partial pressure of CO2 (pCO2) in lakes as a function of lake area, terrestrial net primary productivity (NPP), and precipitation (r2\uffc2\uffa0=\uffc2\uffa0.56), and to create the first high\uffe2\uff80\uff90resolution, circumboreal map (0.5\uffc2\uffb0) of lake pCO2. The map of\uffc2\uffa0pCO2 was combined with lake area from the recently published GLOWABO database and three different estimates of the gas transfer velocity k to produce a resulting map of CO2 evasion (FCO2). For the boreal region, we estimate an average, lake area weighted, pCO2 of 966 (678\uffe2\uff80\uff931,325) \uffce\uffbcatm and a total\uffc2\uffa0FCO2 of 189 (74\uffe2\uff80\uff93347) Tg\uffc2\uffa0C\uffc2\uffa0year\uffe2\uff88\uff921, and evaluate the corresponding uncertainties based on Monte Carlo simulation. Our estimate of FCO2 is approximately twofold greater than previous estimates, as a result of methodological and data source differences. We use our results along with published estimates of the other C fluxes through inland waters to derive a C budget for the boreal region, and find that FCO2 from lakes is the most significant flux of the land\uffe2\uff80\uff90ocean aquatic continuum, and of a similar magnitude as emissions from forest fires. Using the model and applying it to spatially resolved projections of terrestrial NPP and precipitation while keeping everything else constant, we predict a 107% increase in boreal lake FCO2 under emission scenario RCP8.5 by 2100. Our projections are largely driven by increases in terrestrial NPP over the same period, showing the very close connection between the terrestrial and aquatic C cycle.Droughts affect ecosystems at multiple time scales, but their sub\uffe2\uff80\uff90seasonal legacy effects on vegetation activity remain unclear. Combining the satellite\uffe2\uff80\uff90based enhanced vegetation index MODIS EVI with a novel location\uffe2\uff80\uff90specific definition of the growing season, we quantify drought impacts on sub\uffe2\uff80\uff90seasonal vegetation activity and the subsequent recovery in the Northern Hemisphere. Drought legacy effects are quantified as changes in post\uffe2\uff80\uff90drought greenness and sensitivity to climate. We find that greenness losses under severe drought are partially compensated by a \uffe2\uff88\uffbc+5% greening within 2\uffe2\uff80\uff936 growing\uffe2\uff80\uff90season months following the droughts, both in woody and herbaceous vegetation but at different timings. In addition, post\uffe2\uff80\uff90drought sensitivity of herbaceous vegetation to hydrological conditions increases noticeably at high latitudes compared with the local normal conditions, regardless of the choice of drought time scales. In general, the legacy effects on sensitivity are larger in herbaceous vegetation than in woody vegetation.

Abstract. Riverine Fe input is the primary Fe source to the ocean. This study is focused on the distribution of Fe along the Lena River freshwater plume in the Laptev Sea using samples from a 600\u2009km long transect in front of the Lena River mouth. Separation of the particulate (>\u20090.22\u2009\u00b5m), colloidal (0.22\u2009\u00b5m\u20131\u2009kDa), and truly dissolved (\u200999\u2009% of particulate Fe and about 90\u2009% of the colloidal Fe was observed across the shelf, while the truly dissolved phase was almost constant across the Laptev Sea. Thus, the truly dissolved Fe could be an important source of bioavailable Fe for plankton in the central Arctic Ocean, together with the colloidal Fe. Fe-isotope analysis showed that the particulate phase and the sediment below the Lena River freshwater plume had negative \u03b456Fe values (relative to IRMM-14). The colloidal Fe phase showed negative \u03b456Fe values close to the river mouth (about \u22120.20\u2009\u2030) and positive \u03b456Fe values in the outermost stations (about +0.10\u2009\u2030). We suggest that the shelf zone acts as a sink for Fe particles and colloids with negative \u03b456Fe values, representing chemically reactive ferrihydrites. While the positive \u03b456Fe values of the colloidal phase within the outer Lena River freshwater plume, might represent Fe-oxyhydroxides, which remain in the water column, and will be the predominant \u03b456Fe composition in the Arctic Ocean.

", "keywords": ["particles", "QE1-996.5", "Ecology", "truly dissolved iron", "Geology", "Geokemi", "Lena River Plume", "iron isotopes", "01 natural sciences", "estuarine mixing", "6. Clean water", "Geovetenskap och relaterad milj\u00f6vetenskap", "Geochemistry", "iron particles", "Life", "colloids", "13. Climate action", "QH501-531", "Laptev Sea", "Fe isotopes", "14. Life underwater", "Earth and Related Environmental Sciences", "QH540-549.5", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://bg.copernicus.org/articles/16/1305/2019/bg-16-1305-2019.pdf"}, {"href": "https://doi.org/2799682173"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Biogeosciences", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "2799682173", "name": "item", "description": "2799682173", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/2799682173"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2018-04-26T00:00:00Z"}}, {"id": "PMC9152356", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-24T16:27:13Z", "type": "Journal Article", "created": "2022-05-17", "title": "Interacting Bioenergetic and Stoichiometric Controls on Microbial Growth", "description": "

Microorganisms function as open systems that exchange matter and energy with their surrounding environment. Even though mass (carbon and nutrients) and energy exchanges are tightly linked, there is a lack of integrated approaches that combine these fluxes and explore how they jointly impact microbial growth. Such links are essential to predicting how the growth rate of microorganisms varies, especially when the stoichiometry of carbon- (C) and nitrogen (N)-uptake is not balanced. Here, we present a theoretical framework to quantify the microbial growth rate for conditions of C-, N-, and energy-(co-) limitations. We use this framework to show how the C:N ratio and the degree of reduction of the organic matter (OM), which is also the electron donor, availability of electron acceptors (EAs), and the different sources of N together control the microbial growth rate under C, nutrient, and energy-limited conditions. We show that the growth rate peaks at intermediate values of the degree of reduction of OM under oxic and C-limited conditions, but not under N-limited conditions. Under oxic conditions and with N-poor OM, the growth rate is higher when the inorganic N (NInorg)-source is ammonium compared to nitrate due to the additional energetic cost involved in nitrate reduction. Under anoxic conditions, when nitrate is both EA and NInorg-source, the growth rates of denitrifiers and microbes performing the dissimilatory nitrate reduction to ammonia (DNRA) are determined by both OM degree of reduction and nitrate-availability. Consistent with the data, DNRA is predicted to foster growth under extreme nitrate-limitation and with a reduced OM, whereas denitrifiers are favored as nitrate becomes more available and in the presence of oxidized OM. Furthermore, the growth rate is reduced when catabolism is coupled to low energy yielding EAs (e.g., sulfate) because of the low carbon use efficiency (CUE). However, the low CUE also decreases the nutrient demand for growth, thereby reducing N-limitation. We conclude that bioenergetics provides a useful conceptual framework for explaining growth rates under different metabolisms and multiple resource-limitations.