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1 NEW Allied 26.99 MM DIA GEN3SYS XTK Carbide Drill Insert C2 AMEC AM200 (S838)
$12
1 NEW Allied 26.99 MM DIA GEN3SYS XTK Carbide Drill Insert C2 AMEC AM200 (S838)
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Item specifics
Condition:
New – Open box: An item in excellent, new condition with no functional defects. The item may be ... New – Open box: An item in excellent, new condition with no functional defects. The item may be missing original packaging and may have been used for testing or demo purposes. The item includes accessories found with the original product and may include a warranty. See the seller's listing for full details and description.
Model:
GEN3SYS
Insert Type:
Drill Insert
Country/Region of Manufacture:
United States
MPN:
26.99 MM (1.063")
Brand:
Allied Machine amp; Engineering
Insert Material:
Carbide
1 NEW Allied 26.99 MM DIA GEN3SYS XTK Carbide Drill Insert C2 AMEC AM200 (S838)
The following lists the recent preprints posted on EGUsphere with BG-related topics, the recent preprints posted in BG’s discussion forum, as well as final revised papers published recently in BG.
Fertilizer-induced ammonia detrimentally affects the environment by not only directly damaging ecosystems but also indirectly altering climate and soil fertility. To quantify these secondary impacts, we enabled CESM to simulate ammonia emission, chemical evolution, and deposition as a continuous cycle. If synthetic fertilizer use is to soar by 30 % from today's level, we showed that the counteracting impacts will increase the global ammonia emission by 3.3 Tg N per year.
Arctic permafrost ecosystems may release large amounts of carbon under warmer future climates and may therefore accelerate global climate change. Our study investigated how long-term grazing by large animals influenced ecosystem characteristics and carbon budgets at a Siberian permafrost site. Our results demonstrate that such management can contribute to stabilizing ecosystems to keep carbon in the ground, particularly through drying soils and reducing methane emissions.
Marina Corrêa Scalon, Imma Oliveras Menor, Renata Freitag, Karine Silva Peixoto, Sami W. Rifai, Beatriz Schwantes Marimon, Ben Hur Marimon, and Yadvinder Malhi
Preprint under review for BG(discussion: open, 0 comments)
Short summary
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We investigated dynamic nutrient flow and demand in a typical savanna and a transition forest to understand how similar soils and the same climate dominated by savanna vegetation can also support forest-like formations. Savanna relied in nutrient resorption from wood, and nutrient demand was equally partitioned between leaves, wood and fine roots. Transition forest relied on resorption from the canopy biomass and nutrient demand was predominantly driven by leaves.
Preprint under review for BG(discussion: open, 0 comments)
Short summary
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This study explores the seasonal, interannual and long-term drivers of the South Atlantic air-sea CO2 flux. Our analysis showed seasonally, sea surface temperatures dominate in the subtropics, and the subpolar regions correlated with biological processes. Interannually, the El Nino Southern Oscillation correlated with the CO2 flux by modifying sea surface temperatures and biological activity. Long term trends indicated an important biological contribution to changes in the air-sea CO2 flux.
Rey Harvey Suello, Simon Lucas Hernandez, Steven Bouillon, Jean-Philippe Belliard, Luis Dominguez-Granda, Marijn Van de Broek, Andrea Mishell Rosado Moncayo, John Ramos Veliz, Karem Pollette Ramirez, Gerard Govers, and Stijn Temmerman
This research shows indications that the age of the mangrove forest and its position along a deltaic gradient (upstream–downstream) play a vital role in the amount and sources of carbon stored in the mangrove sediments. Our findings also imply that carbon capture by the mangrove ecosystem itself contributes partly but relatively little to long-term sediment organic carbon storage. This finding is particularly relevant for budgeting the potential of mangrove ecosystems to mitigate climate change.
A 5-year record of long-chain mid-chain diol export flux and composition is presented with a 1- to 3-week resolution sediment trap CBeu (in the NW African upwelling). All environmental parameters as well as the diol composition are dominated by the seasonal cycle, albeit with different phase relations for temperature and upwelling. Most diol-based proxies are dominated by upwelling. The long-chain diol index reflects temperatures of the oligotrophic summer sea surface.
Currently people are very concerned about vegetation changes and their driving factors, including natural and anthropogenic drivers. In this study, a general browning trend is found in Syria during 2001–2018, indicated by the vegetation index. We found that land management caused by social unrest is the main cause of this browning phenomenon. The mechanism initially reported here highlights the importance of land management impacts at the regional scale.
As leaching is a major pathway of nitrogen and phosphorus loss in forest soils, we investigated several potential drivers in two contrasting beech forests. The composition of leachates, obtained by zero-tension lysimeters, varied by season, and climatic extremes influenced the magnitude of leaching. Effects of nitrogen and phosphorus fertilization varied with soil nutrient status and sorption properties, and leaching from the low-nutrient soil was more sensitive to environmental factors.
The threat posed by climate change to prairie pothole wetlands is well documented, but gaps remain in our ability to make meaningful predictions about how prairie pothole wetlands will respond. We integrate aspects of topography, land cover/land use and climate to model the permanence class of tens of thousands of wetlands at the western edge of the Prairie Pothole Region.
Preprint under review for BG(discussion: open, 0 comments)
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In this study, we relied on a properly controlled laboratory experiment to test the model’s capability of simulating the dominant microbial processes and the emissions of one greenhouse gas (nitrous oxide, N2O) from agricultural soils. This study reveals important processes and parameters that regulate N2O emissions in the investigated model framework, and also suggests future steps of model development which has implications on the broader communities of ecosystem modelers.
Preprint under review for BG(discussion: open, 0 comments)
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Reconstructions of past CO2 concentrations rely on proxy estimates, with one line of proxies relying on the CO2-dependence of stable carbon isotope fractionation in marine phytoplankton. Culturing experiments provide insight into which processes may impact this. We found, however, that the methods with which these culturing experiments are performed also influence 13C fractionation. Caution should therefore be taken when extrapolating results from these experiments to proxy applications.
Preprint under review for BG(discussion: open, 0 comments)
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According to our results, we found that the variations of POC were characterized with higher proportions of autochthonous components in summer and the size spectra of DOC illustrated a distinct seasonal variation pattern. Moreover, the strong correlation of δ13C values between HMW-DOC and POC suggested their relationships in origin and composition. Together with available literature data, DOC concentrations, POC (%), δ13C, and δ15N all showed a significant increase over the past decades.
Preprint under review for BG(discussion: open, 0 comments)
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Excess radiation and low temperature exacerbate drought impacts on stomatal conductance (gs) among transects. Primary determinant of drought on gs was soil moisture in Loess Plateau (LP) and Mongolian Plateau (MP), and vapor pressure deficit in Tibetan Plateau (TP). Radiation exhibited negative effect on gs via drought within transects, while temperature had positive effects on gs in LP, no effects in MP, and negative effects in TP.
Maiju Linkosalmi, Juha-Pekka Tuovinen, Olli Nevalainen, Mikko Peltoniemi, Cemal Melih Taniş, Ali Nadir Arslan, Juuso Rainne, Annalea Lohila, Tuomas Laurila, and Mika Aurela
Preprint under review for BG(discussion: open, 0 comments)
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The vegetation phenology was monitored with digital cameras in three northern peatlands during five growing seasons. The greenness index derived from the images was highest at the most nutrient-rich site. Greenness indicated the main phases of phenology and correlated with CO2 uptake, though this was mainly related to the common seasonal cycle. The cameras and Sentinel-2 satellite showed consistent results, but more frequent satellite data are needed for reliable detection of phenological phases.
Wildfire-derived molecules are ubiquitous in the aquatic environment, but their biological fate remains understudied. We have evaluated the compositional changes that occur to wildfire-derived molecules after incubation with soil microbes. We observe a significant degradation but also a production of numerous new labile molecules. Our results indicate that wildfire-derived molecules can be broken down and the carbon and nitrogen therein can be incorporated into microbial food webs.
This work focuses on one of the essential pathways of mycorrhizal impact on C cycles: the mediation of plant litter decomposition. We present a model based on litter chemical quality which precludes a conclusive examination of mycorrhizal impacts on soil C. It improves long-term decomposition predictions and advances our understanding of litter decomposition dynamics. It creates a benchmark in quantitatively examining the impacts of plant–microbe interactions on soil C dynamics.
Preprint under review for BG(discussion: open, 0 comments)
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At low water level parts of the bottom of rivers fall dry. These beaches or mudflats are emitting the greenhouse gas carbon dioxide (CO2) to the atmosphere. We found that those emissions are caused by microbial reactions in the sediment and that they are changing with time. Emissions were influenced by many factors like temperature, water level, rain, plants, and light.
As carbon (C) and greenhouse gas (GHG) research has adopted appropriate technology and approach (AT&A), low-cost instruments, open-source software, and participatory research and their results were well accepted by scientific communities. In terms of cost, feasibility, and performance, the integration of low-cost and low-technology, participatory and networking-based research approaches can be AT&A for enhancing C and GHG research in developing countries.
During an oceanographic cruise conducted in January 2020 in the south-western Indian Ocean, we observed very low CO2 concentrations associated with a strong phytoplankton bloom that occurred south-east of Madagascar. This biological event led to a strong regional CO2 ocean sink not previously observed.
Preprint under review for BG(discussion: open, 0 comments)
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Large-diameter trees have an overwhelming effect on aboveground biomass (AGB) in successional temperate forests. Moreover, they mediate the effects of abiotic drivers on AGBs in overstory and whole community and play an important role in both controlling the diversity and structure of remaining trees. In addition, our study highlights the mechanisms of biomass dominance of large-diameter trees associated with self-thinning process and resource availability in successional forests.
A glacial–interglacial methane-fuelled redistribution of reactive phosphorus between the oceanic and sedimentary phosphorus reservoirs can occur in the ocean when falling sea level lowers the pressure on the seafloor, destabilizes methane hydrates, and triggers the dissolution of P-bearing iron oxides. The mass of phosphate potentially mobilizable from the sediment is similar to the size of the current oceanic reservoir. Hence, this process may play a major role in the marine phosphorus cycle.
Preprint under review for BG(discussion: open, 0 comments)
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Empirical work that estimates the age of respired CO2 from vegetation tissue shows that it may take from years to decades to respire previously produced photosynthates. However, many ecosystem models represent respiration processes in a form that cannot reproduce these observations. In this contribution, we attempt to provide compelling evidence based on recent research, with the aim to promote a change in the predominant paradigm implemented in ecosystem models.
In this study, we investigate the chemical diversity and abundance of microbial lipids as markers of organic matter sources in the deepest points of the Atacama Trench sediments and compare them to similar lipid stocks in shallower surface sediments and in the overlying water column. We evaluate possible organic matter provenance and some potential chemical adaptations of the in situ microbial community to the extreme conditions of high hydrostatic pressure in hadal realm.
Allanah Joy Paul, Lennart T. Bach, Javier Arístegui, Elisabeth von der Esch, Nauzet Hernández-Hernández, Jonna Piiparinen, Laura Ramajo, Kristian Spilling, and Ulf Riebesell
Preprint under review for BG(discussion: open, 1 comment)
Short summary
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We investigated how different deep water chemistry and biology modulate the response of surface plankton communities to upwelling in the Peruvian coastal zone. Our results show that the most influential drivers were the ratio of inorganic nutrients (NOx : PO43-) and the microbial community present in deep water. These led to unexpected responses in the phytoplankton assemblage that could not be predicted by the amount of inorganic nutrients alone.
Preprint under review for BG(discussion: open, 0 comments)
Short summary
Short summary
Marine heatwaves (MHWs) are a frequent event in the Northeast Pacific with a large impact on the region's ecosystems. Large phytoplankton in the Northeast Pacific Transition Zone are greatly affected with less of an impact in the Alaskan Gyre. For small phytoplankton, we find MHWs increase the spring small phytoplankton population in both regions thanks to shallow mixed layers and lower light limitation. In both zones, this results in a 2 % decrease in the ratio of large to small phytoplankton.
Rahayu Adzhar, Douglas I. Kelley, Ning Dong, Charles George, Mireia Torello Raventos, Elmar Veenendaal, Ted R. Feldpausch, Oliver L. Phillips, Simon L. Lewis, Bonaventure Sonké, Herman Taedoumg, Beatriz Schwantes Marimon, Tomas Domingues, Luzmila Arroyo, Gloria Djagbletey, Gustavo Saiz, and France Gerard
The MODIS Vegetation Continuous Fields (VCF) product underestimates tree cover compared to field data and could be underestimating tree cover significantly across the tropics. VCF is used to represent land cover or validate model performance in many land surface and global vegetation models and to train finer-scaled Earth observation products. Because underestimation in VCF may render it unsuitable for training data and bias model predictions, it should be calibrated before use in the tropics.
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Darren R. Clark, Andrew P. Rees, Charissa M. Ferrera, Lisa Al-Moosawi, Paul J. Somerfield, Carolyn Harris, Graham D. Quartly, Stephen Goult, Glen Tarran, and Gennadi Lessin
Measurements of microbial processes were made in the sunlit open ocean during a research cruise (AMT19) between the UK and Chile. These help us to understand how microbial communities maintain the function of remote ecosystems. We find that the nitrogen cycling microbes which produce nitrite respond to changes in the environment. Our insights will aid the development of models that aim to replicate and ultimately project how marine environments may respond to ongoing climate change.
Preprint under review for BG(discussion: open, 0 comments)
Short summary
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Although hydraulic redistribution (HR) is a well-documented phenomenon, whether it is a passive happy accident or actively controlled by roots is not well understood. Our modeling study suggests HR is long-range feedback between roots that inhabit heterogeneously resourced soil regions. When nutrients and organic matter are concentrated in shallow layers that experience frequent drying, root-exudation facilitated HR allows plants to mineralize and extract the otherwise inaccessible nutrients.
Preprint under review for BG(discussion: open, 0 comments)
Short summary
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The distinct carbon isotopic signatures of C3 and C4 plants are widely used to reconstruct past hydroclimate, where more C3 plants represent wetter and C4 plants drier conditions. Here we examine if plant isotopic signatures in the Godavari River basin in peninsular India follow the global patterns. We find that Godavari plants have a distinct isotopic signature and are influenced by drought stress, which introduces a bias in C3/C4 plant estimates and associated hydroclimate reconstructions.
Peatlands have been subject to a range of land management regimes over the past century. This has affected the amount of carbon that drains into surrounding streams and rivers. In our study, we measured carbon concentrations in streams draining from drained, non-drained, and restored areas of the Flow Country blanket bog in N Scotland. We found that drained peatland had higher concentrations and fluxes of carbon relative to non-drained areas. Restored peatland areas were highly variable.
Lena Wohlgemuth, Pasi Rautio, Bernd Ahrends, Alexander Russ, Lars Vesterdal, Peter Waldner, Volkmar Timmermann, Nadine Eickenscheidt, Alfred Fürst, Martin Greve, Peter Roskams, Anne Thimonier, Manuel Nicolas, Anna Kowalska, Morten Ingerslev, Päivi Merilä, Sue Benham, Carmen Iacoban, Günter Hoch, Christine Alewell, and Martin Jiskra
Gaseous mercury is present in the atmosphere all over the globe. During the growing season, plants take up mercury from the air in a similar way as CO2. We investigated which factors impact this vegetational mercury uptake by analyzing a large dataset of leaf mercury uptake rates of trees in Europe. As a result, we conclude that mercury uptake is foremost controlled by tree-intrinsic traits like physiological activity but also by climatic factors like dry conditions in the air and in soils.
Saharan dust deposition of nutrients and trace metals is crucial to microbes in the Mediterranean Sea. Here, we tested the response of microbial and viral communities to simulated dust deposition under present and future conditions of temperature and pH. Overall, the effect of the deposition was dependent on the initial microbial assemblage, and future conditions will intensify microbial responses. We observed effects on trophic interactions, cascading all the way down to viral processes.
Information on the marine carbon dioxide system along the northeast Pacific Inside Passage has been limited. To address this gap, we instrumented an Alaskan ferry in order to characterize the marine carbon dioxide system in this region. Data over a 2-year period were used to assess drivers of the observed variability, identify the timing of severe conditions, and assess the extent of contemporary ocean acidification as well as future levels consistent with a 1.5 °C warmer climate.
Brendan Byrne, Junjie Liu, Yonghong Yi, Abhishek Chatterjee, Sourish Basu, Rui Cheng, Russell Doughty, Frédéric Chevallier, Kevin W. Bowman, Nicholas C. Parazoo, David Crisp, Xing Li, Jingfeng Xiao, Stephen Sitch, Bertrand Guenet, Feng Deng, Matthew S. Johnson, Sajeev Philip, Patrick C. McGuire, and Charles E. Miller
Preprint under review for BG(discussion: open, 0 comments)
Short summary
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Growing season plant growth draws CO2 out of the atmosphere while respiration releases CO2 back to the atmosphere, driving seasonal variations in atmospheric CO2 that can be observed by satellites, such as the Orbiting Carbon Observatory-2 (OCO-2). Using OCO-2 CO2 data with space-based constraints on plant growth, we show that the permafrost-rich northeast Eurasia has a strong seasonal release of CO2 during the autumn, hinting at a unexpectedly large respiration signal from soils.
Preprint under review for BG(discussion: open, 0 comments)
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An important uncertainty in the modelling of methane emissions from natural wetlands is the wetland area. It is important to get the spatiotemporal covariance between the variables that drive methane emissions right for accurate quantification. Using high-resolution wetland and soil carbon maps, in combination with a simplified methane emission model that is coarsened in six steps from 0.005° to 1°, we find a strong relation between wetland emissions and the model resolution.
Part of the organic matter produced by plankton in the upper ocean is exported to the deep ocean. This process, known as the biological carbon pump, is key for the regulation of atmospheric carbon dioxide and global climate. However, the dynamics of organic particles below the upper ocean layer are not well understood. Here we compared the measurements acquired by autonomous robots in the top 1000 m of the ocean to a numerical model, which can help improve future climate projections.
Preprint under review for BG(discussion: open, 1 comment)
Short summary
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Excessive leaching of nitrate from forested catchments during storm events degrades water quality and causes eutrophication in downstream areas. Thus, tracing the source of nitrate increase during storm events in forested streams is important for sustainable forest management. On the basis of the isotopic compositions of stream nitrate, including Δ17O, this study clarified that the source of stream nitrate increase during storm events is soil nitrate in the riparian zone.
Arctic permafrost landscapes feature many water bodies. In contrast to the terrestrial parts of the landscape, the water bodies release carbon to the atmosphere. We compare carbon dioxide and methane fluxes from small water bodies to the surrounding tundra and find not accounting for the carbon dioxide emissions leads to an overestimation of the tundra uptake by 11 %. Consequently, changes in hydrology and water body distribution may substantially impact the overall carbon budget of the Arctic.
Karis J. McFarlane, Heather M. Throckmorton, Jeffrey M. Heikoop, Brent D. Newman, Alexandra L. Hedgpeth, Marisa N. Repasch, Thomas P. Guilderson, and Cathy J. Wilson
Planetary warming is increasing seasonal thaw of permafrost, making this extensive old carbon stock vulnerable. In northern Alaska, we found more and older dissolved organic carbon in small drainages later in summer as more permafrost was exposed by deepening thaw. Younger and older carbon did not differ in chemical indicators related to biological lability suggesting this carbon can cycle through aquatic systems and contribute to greenhouse gas emissions as warming increases permafrost thaw.
Measurements on sea-dwelling shelled organisms called foraminifera retrieved from deep-sea sediment cores have been used to reconstruct sea surface temperature (SST) variation. To evaluate the method, we use a computer model to simulate millions of single foraminifera and how they become mixed in the sediment after being deposited on the seafloor. We compare the SST inferred from the single foraminifera in the sediment core to the true SST in the water, thus quantifying method uncertainties.
Marie Barbieux, Julia Uitz, Alexandre Mignot, Collin Roesler, Hervé Claustre, Bernard Gentili, Vincent Taillandier, Fabrizio D'Ortenzio, Hubert Loisel, Antoine Poteau, Edouard Leymarie, Christophe Penkerc'h, Catherine Schmechtig, and Annick Bricaud
This study assesses marine biological production in two Mediterranean systems representative of vast desert-like (oligotrophic) areas encountered in the global ocean. We use a novel approach based on non-intrusive high-frequency in situ measurements by two profiling robots, the BioGeoChemical-Argo (BGC-Argo) floats. Our results indicate substantial yet variable production rates and contribution to the whole water column of the subsurface layer, typically considered steady and non-productive.
Hanna Maria Kauko, Philipp Assmy, Ilka Peeken, Magdalena Róźańska, Józef M. Wiktor, Gunnar Bratbak, Asmita Singh, Thomas J. Ryan-Keogh, and Sebastien Moreau
Preprint under review for BG(discussion: open, 1 comment)
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This article studies phytoplankton (microscopic plants in the ocean capable of photosynthesis) in Kong Håkon VII Hav in the Southern Ocean. Different species play different roles in the ecosystem and it is therefore important to assess the species composition. We observed that phytoplankton blooms in this area are formed by large diatoms with strong silica armours, which can lead to high silica (and sometimes carbon) export to depth and be important prey for krill.
Faecal biomarker analyses present a useful tool in geoarcheological research. For a better understanding of the lives of our ancestors in alpine regions, we investigated modern livestock faeces and Holocene soils at the prehistorical encampment site of Ullafelsen in the Fotsch Valley, Stubai Alps, Austria. Initial results show a high input of livestock faeces and a negligible input of human faeces for this archeological site. Future studies will focus on mire archives in the Fotsch Valley.
Carbon dioxide and methane contribute to global warming. What can we do? We can build wetlands: they store carbon dioxide and should cause global cooling. But when first built they produce excess methane. Eventually built wetlands will cause cooling, but it may take decades or even centuries. How we build wetlands matters. We show that a common practice, using organic matter, such as manure, can make a big difference whether or not the wetlands we build start global cooling within our lifetime.
James P. J. Ward, Katherine R. Hendry, Sandra Arndt, Johan C. Faust, Felipe S. Freitas, Sian F. Henley, Jeffrey W. Krause, Christian März, Allyson C. Tessin, and Ruth L. Airs
Preprint under review for BG(discussion: open, 1 comment)
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The seafloor plays an important role in the cycling of silicon (Si), a key nutrient that promotes marine primary productivity. In our model study, we disentangle the major controls on the seafloor Si cycle to better anticipate the impacts of continued warming and sea ice melt in the Barents Sea. We uncover a coupling of the iron redox and Si cycles, dissolution of lithogenic silicates and authigenic clay formation, comprising a Si sink that could have implications for the Arctic Ocean Si budget.
Preprint under review for BG(discussion: open, 2 comments)
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The biomass of forests is determined by forest growth and mortality. These quantities can be estimated with different methods such as inventories, remote sensing and modelling. These methods are usually being applied at different spatial scales. The scales influence the obtained frequency distributions of biomass, growth and mortality. This study suggests how to transfer between scales, when using forest models of different complexity for a tropical forest.
James Stegen, Sarah Fansler, Malak Tfaily, Vanessa Garayburu-Caruso, Amy Goldman, Robert Danczak, Rosalie Chu, Lupita Renteria, Jerry Tagestad, and Jason Toyoda
Preprint under review for BG(discussion: open, 2 comments)
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Rivers are vital to Earth and in rivers, organic matter (OM) is an energy source for microbes that make greenhouse gas and remove contaminants. To predict Earth’s future requires understanding how and why river OM is transformed. Our results help meet this need. We found that the processes influencing OM transformations diverge between river water and riverbed sediments. This can be used to build new models for predicting the future of rivers and, in turn, the Earth system.
Preprint under review for BG(discussion: open, 1 comment)
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Cleavage of proteins to smaller nitrogen compounds allows microorganisms and plants to exploit the largest nitrogen reservoir in soils and is considered the bottleneck in soil organic nitrogen cycling. Results from soils covering a European transect show that protein turnover is constrained by soil geochemistry, shifts in climate and associated alterations in soil weathering and should be considered as driver of soil nitrogen availability with repercussions on carbon cycle processes.
A stream is defined by flowing water, but higher flow from storms is also a frequent disturbance. This paper tests how higher flow changes stream metabolism (respiration and photosynthesis, R and P). P was less resistant to changes in flow compared to R, and P took longer to recover from storms than R (2.2 versus 0.6 d). Further work on metabolic responses to flow disturbance is critical given projected increases in storms and the influence of higher flows on ecosystem health and functioning.
Air–sea CO2 fluxes and associated uncertainty over the open ocean to coastal shelves are estimated with a new ensemble-based reconstruction of pCO2 trained on observation-based data. The regional distribution and seasonality of CO2 sources and sinks are consistent with those suggested in previous studies as well as mechanisms discussed therein. The ensemble-based uncertainty field allows identifying critical regions where improvements in pCO2 and air–sea CO2 flux estimates should be a priority.
Preprint under review for BG(discussion: open, 3 comments)
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Our results highlight a marked decrease of high carbon accumulation rates in Andean peatlands over the last decades due to the diminution in melt water inflow generated by the retreat of glaciers as a consequence of regional warming. These marked changes stress the high ecological sensitivity of these peatlands, endangering their outstanding role in the regional (and even global) C cycle as large C sinks that contribute to the mitigation of global climate change.
Preprint under review for BG(discussion: open, 2 comments)
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Our field experiment tested if a mixture of a nitrogen fixing legume and non-legume cover crop could reduce nitrous oxide (N2O) emissions following tillage, compared to the legume grown alone. We found higher N2O following both legume treatments, compared to those without, and lower emissions from the cover crop mixture at one of the two test sites, suggesting that interactions between cover crop types and soil quality influence N2O emissions.
Preprint under review for BG(discussion: open, 1 comment)
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For two consecutive summers, the bottom waters in southern Cape Cod Bay became severely depleted of dissolved oxygen. Low oxygen levels in bottom waters have never been reported in this area before, and this unprecedented occurrence is likely the result of a new algae species that recently began blooming during the late summer months. We present data suggesting that blooms of this new species are the result of regional climate change including warmer waters and changes in summer winds.
Preprint under review for BG(discussion: open, 0 comments)
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Eddies are ubiquitous in the ocean and alter physical, chemical and biological processes. However, how they affect organic carbon production and consumption is largely unknown. Here we show how an eddy triggers a cascade effect on biomass production and metabolic activities of phyto- and bacterioplankton. Our results may contribute to the improvement of biogeochemical models used to estimate carbon fluxes in the ocean.