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This is the AmeriFlux version of the carbon flux data for the site US-UR0 Baggs - UCRB. Site Description - This tower is located in Baggs, Wyoming, in a grassland ecosystem. The area experiences cold winters and mild summers, with relatively low precipitation and significant snowfall during the winter months. The surrounding landscape consists mainly of grass pastures used for livestock grazing.
This is the AmeriFlux version of the carbon flux data for the site US-UR1 Boulder - UCRB. Site Description - This site is located in Boulder, Wyoming, in a high-altitude grassland ecosystem. The region experiences cold winters and mild summers, with relatively low precipitation throughout the year. Snowfall is common during the winter months, contributing to the seasonal water availability. The landscape is primarily covered by grass vegetation, with some areas supported by a center pivot irrigation system, which helps sustain plant growth in the dry environment.
This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-DFK Dairy Forage Research Center - Kernza. This is the FLUXNET version of the carbon flux data for the site US-DFK Dairy Forage Research Center - Kernza produced by applying the standard ONEFlux (1F) software. Site Description - Crop field (10 acres) in annual and perennial rotation. Alfalfa (2015-2018), intermediate wheatgrass grown for Kernza grain and grass forage (planted September 2019-2023, terminated spring 2024), corn silage (2024), planted in winter wheat (late summer/fall 2024). Winter wheat (2025) followed by alfalfa (to be planted August 2025).
This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-PFr SE4 Tussock-2 CHEESEHEAD 2019. This is the FLUXNET version of the carbon flux data for the site US-PFr SE4 Tussock-2 CHEESEHEAD 2019 produced by applying the standard ONEFlux (1F) software. Site Description - This tower (3m tripod) is located in the southeastern quadrant of the 10 x 10km study domain. It is located in a tussock (0.3 - 1m grasses). Located next to stream.
This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-PAS Florida, Paspalum notatum pasture. This is the FLUXNET version of the carbon flux data for the site US-PAS Florida, Paspalum notatum pasture produced by applying the standard ONEFlux (1F) software. Site Description - Florida cultivated grass (Paspalum notatum) pasture rotationally stocked year-round. Soils are predominatly spodosols, subject to periodoc flooding.
This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site CA-EM2 Shoal Lake Manitoba. This is the FLUXNET version of the carbon flux data for the site CA-EM2 Shoal Lake Manitoba produced by applying the standard ONEFlux (1F) software. Site Description - This tower is located in a freshwater marsh embedded in rangeland/perennial cover in southwestern Manitoba. The wetland is 20.3 ha in size. The wetland vegetation is dominated bulrush with only small pockets of open-water. The surrounding uplands consist of native and tame grasses that are periodically grazed by cattle.
This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site CA-Mtk Mittimatalik (Pond Inlet) Tundra. This is the FLUXNET version of the carbon flux data for the site CA-Mtk Mittimatalik (Pond Inlet) Tundra produced by applying the standard ONEFlux (1F) software. Site Description - Mesic to dry tundra with dwarf shrubs, grasses, forbs, and moss vegitation. Thin organic soil layer of 10 cm with sandy soils.
This is the AmeriFlux version of the carbon flux data for the site US-MCP Moro Cojo Slough, PG&E Treatment Wetland. Site Description - Freshwater coastal wetland, restored in 2016, native grasses and sedges among freshwater ponds, surrounded 400m in each direction by agricultural plots, native plants remove excess agrcultural nitrogen from the soil
This is the AmeriFlux version of the carbon flux data for the site US-ABe Archbold Ungrazed Wetland. Site Description - The studied wetland is embedded within an intensively managed pasture, a common landscape in Florida, with the C4 bahiagrass (Paspalum notatum Flueggé) as forage grass. The wetland is an isolated, seasonal freshwater wetland. Soil was Samsula muck of Samsula Series (hyperthermic Terric Haplosaprists)
This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site CA-SF3 Saskatchewan - Western Boreal, forest burned in 1998. This is the FLUXNET version of the carbon flux data for the site CA-SF3 Saskatchewan - Western Boreal, forest burned in 1998 produced by applying the standard ONEFlux (1F) software. Site Description - The 1998 burn site (F98) was in the east part of Prince Albert National Park, Saskatchewan, in the Waskesiu Fire, ignited by lightning that burned about 1700 ha in July 1998. The pre-fire forest consisted of jack pine and black spruce stands, with some intermixed aspen. The fire was severe, consuming much of the top layer of organic soil and killing all trees. In 2001, much of the regenerating vegetation consisted of aspen saplings about 1 m tall and shorter jack pine and black spruce seedlings. An overstory of dead, leafless jack pine trees dominated at a height of 18 m. Sparse grass and herbs, such as fireweed (Epilobium angustifolium L.) covered the ground. There were a large number of fallen dead trees, mostly perched above the ground and not decomposing quickly.
This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-LS1 San Pedro River Lewis Springs Sacaton Grassland. This is the FLUXNET version of the carbon flux data for the site US-LS1 San Pedro River Lewis Springs Sacaton Grassland produced by applying the standard ONEFlux (1F) software. Site Description - This is a riparian grassland located along an old alluvial terrace along the banks of the entrenched San Pedro River in southeastern Arizona. Site climate is semiarid with monsoonal (Jul-Sep) rainfall. The grasses access groundwater (depth of 2-4 m)from an alluvial aquifer recharged elsewhere. Site water balance is not closed and ET greatly exceeds precipitation. The perennial bunchgrasses use both rainfall, groundwater and occasional flood water. This groundwater-using ecosystem is far more ebulliant and productive than the upland vegetation around it (shrublands and grasslands) outside of the San Pedro River corridor.
This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-CMW Charleston Mesquite Woodland. This is the FLUXNET version of the carbon flux data for the site US-CMW Charleston Mesquite Woodland produced by applying the standard ONEFlux (1F) software. Site Description - Site is a riparian mesquite woodland located along an old alluvial terrace along the banks of the San Pedro River in southeastern Arizona. Site climate is semiarid with monsoonal (Jul-Sep) rainfall. The mesquite trees access groundwater from an alluvial aquifer recharged elsewhere. Site water balance is not closed and ET greatly exceeds precipitation. The understory grasses and forbs are rainfall dependent. This groundwater-dependent ecosystem is far more ebulliant and productive than the upland vegetation around it (shrublands and grasslands).
This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-ABe Archbold Ungrazed Wetland. This is the FLUXNET version of the carbon flux data for the site US-ABe Archbold Ungrazed Wetland produced by applying the standard ONEFlux (1F) software. Site Description - The studied wetland is embedded within an intensively managed pasture, a common landscape in Florida, with the C4 bahiagrass (Paspalum notatum Flueggé) as forage grass. The wetland is an isolated, seasonal freshwater wetland. Soil was Samsula muck of Samsula Series (hyperthermic Terric Haplosaprists)
New capabilities to predict, design and control the chemistries of carbon could answer a global imperative to transition from fossil-based to sustainable transportation fuels. While the use of inexpensive hydrocarbons has been an unparalleled achievement and enabler of economic prosperity for many nations, singular dependence upon crude oil has given rise to systemic vulnerabilities in climate, energy, economic, and national security. Lignocellulosic biomass, a renewable and carbon-neutral resource, has the potential to displace an estimated annual equivalent of three billion barrels of oil in the U.S. alone (National Research Council 2009, U. S. Department of Energy, 2011). However, biomass has only one-third the energy density of crude oil (Agrawal and Singh 2009, Richard 2010) and lacks petroleum’s versatility as a feedstock for fuels and chemicals. These limitations keep biomass conversion below the efficiency level needed for strategic impact while the scientific challenge of routing carbon from one molecular context to another remains unmet. In 2009, the Center for Direct Catalytic Conversion of Biomass to Biofuels (C3Bio) recognized the potential of chemical catalysis and fast pyrolysis to overcome such limitations by transforming the main components of biomass (cellulose, xylan, and lignin) from grasses and trees directly to liquid hydrocarbons and aromatic co-products. Enabled by the EFRC high-risk, high-reward approach to grand challenge science, C3Bio researchers have been key national players in disrupting the conventional paradigm of the cellulosic biorefinery into a new future of “no carbon left behind”—the full utilization of carbon from plant cell walls in energy-dense fuels (Fig. 1). We identified catalytic and fast-pyrolytic pathways that utilize cellulose, xylan and, most significantly, lignin. We developed catalytic processes that deoxygenate and transform monomers and isolated polymers into useful products and tested their use with intact biomass. We gained control of lignin synthesis within plants and initiated tailoring biomass to its end-use through the tools of plant molecular biology and genetic engineering. C3Bio breakthroughs have increased the energy density of biomass-derived substrates via catalytic and pyrolytic conversions into products such as benzoquinones, furfural and hydroxymethylfurfural, levoglucosan and levulinic acid, methoxypropylphenols and propylbenzene. Such advances in biomass conversion would not have been possible without simultaneous advances in analytical instrumentation and methodologies, and imaging technologies and applications. The legacy science developed by C3Bio enables design and control strategies for achieving a targeted product portfolio of fuel and chemical feedstocks from a diverse range of native and tailored biomass. Our research provides the knowledge base required for a bio-economy with product streams as diverse in functionality as those of the petrochemical industry. Coupling targeted computational modeling with experimentation, we achieved: (1) fundamental understanding of biopolymers and cell wall architecture assembly, (2) discovery of new chemistries that allow the development of highly selective pathways to fuels and desirable chemicals, and (3) an integrated systems-level understanding to control catalytic and pyrolytic pathways.
The Site A/Plot M, Decommissioned Reactor Site was inspected on September 24, 2020. Site A/Plot M is located in the Palos Area Preserves, operated by the Forest Preserve District of Cook County. The site was found to be in good condition with minimal erosional concerns across the grass covered mound at Plot M. Landscaping timbers installed along the footpath north of Plot M is effective in reducing erosion down the hill. Erosion concerns at Plot M are being addressed by Argonne National Laboratory (ANL). The bike trail installed by Cook County Forest Preserve to the east of Plot M has helped reduce traffic at the site. The Plot M monument appears solid with no visible cracks. The Site A monument has several cracks present that will possibly widen over time. No cause for a follow up inspection was identified.
Biogeochemical cycles within mountainous watersheds are key regulators of ecosystem carbon storage and downstream nutrient loadings, and they have shown to be particularly vulnerable to climate change impacts. Increasing temperature and persistent droughts have already dramatically changed vegetation cover across the mountainous western US, with unknown consequences for soil carbon and nutrient cycles belowground. What remains elusive is to what extent associated changes in root-soil interactions may mobilize the vast pool of organic matter (OM) that has been stabilized by associations with minerals for centuries or millennia. Although plant root-driven OM mobilization from minerals may be a central control on carbon loss and nutrient export, such mechanisms are currently missing from conceptual and numerical models. The overall objective of this Exploratory Project is to identify the biogeochemical mechanisms by which roots destabilize mineral-associated organic matter (MAOM) and the cumulative impact on carbon and nutrient fate. To accomplish this goal, we integrated well-controlled laboratory experiments with in-field measurements and a scalable modeling approach. First, we conducted model system experiments to assess the vulnerability of MAOM to exudate-mediated mechanisms. Our results show that common root exudates effectively destabilize MAOM not only through direct, ligand-driven mobilization mechanisms, but also indirect, microbially-mediated mechanisms relying on secondary metabolites and enzymes. We further found that OM bound to poorly crystalline Fe and Al (hydr)oxides is more vulnerable to exudate-induced destabilization than OM bound to more crystalline phases, particularly in response to direct, ligand-promoted mechanisms. These findings demonstrate that the stability of MAOM is not just a function of their inherent properties, but also will depend in large parts on the ability of plant roots and microbes to produce exudates capable of triggering suitable mobilization mechanisms. We further employed a well-controlled rhizobox approach, combining advanced microsensor and mass spectrometry techniques, to resolve spatiotemporal variations in the composition and availability of exudates along single growing roots of grasses. Our results show that the composition of functionally relevant exudate compounds varies at extremely short time scales, seemingly shifting from ligands such as aromatic acids around root tips to less reactive metabolites such as amino acids around mature root segments. These results suggest a prevalence of direct MAOM mobilization mechanisms around the root tip, while indirect MAOM mobilization strategies may dominate around more mature root segments. Additionally, we utilized microsensor measurements in rhizoboxes to parameterize a rhizosphere (hydro)biogeochemistry reactive transport model (eSTOMP-ROOTS). The resulting model was used to assess how root exudations affects the stability of MAOM. Model simulations show that diel pulses of root exudation are strong enough to cause oscillations in biogeochemical conditions—particularly in pH, oxygen concentrations, and microbial activity— that repeatedly disrupt MAOM. Finally, we assessed field-scale impacts of root-driven MAOM destabilization over short and long time scales. A combination of in-field incubations and field-based characterizations showed that MAOM may not only be vulnerable to seasonal variations in root activity, but also to root-driven weathering over pedogenic time scales. In sum, results from our Exploratory Award highlight the strong control plant roots exert on MAOM mobilization and, thus, on the potential for carbon and nutrient export from watersheds.
Lignocellulosic biomass has only one-third the energy density of crude oil and lacks petroleum’s versatility as a feedstock for fuels and chemicals. Since 2009, the Center for direct Catalytic Conversion of Biomass to Biofuels (C3Bio) has recognized the potential of chemical catalysis and fast-pyrolysis to overcome such limitations by transforming the main components of biomass (cellulose, xylan, and lignin) from grasses and trees directly to liquid hydrocarbons and aromatic co-products. In 2014, C3Bio proposed to develop critical systems-level understanding of how biomass structural complexity at molecular, nanoscale, and mesoscale levels impacts the yields and selectivities of desired products from catalytic and pyrolytic transformations. Our long-term goal was to gain unprecedented control of effective routing of carbon: we aimed to specify both the structures within, and the reaction products from, lignocellulosic biomass. Enabled by the EFRC high-risk, high-reward approach to grand challenge science, our interdisciplinary team of plant biologists, chemists, and chemical engineers disrupted the conventional paradigm of the cellulosic biorefinery into a new future of “no carbon left behind” - the full utilization of carbon from plant cell walls in energy-dense fuels.
The present document, the Latin American HECAP Physics Briefing Book, is the result of this ambitious grass roots effort. This report contains the work performed by the Preparatory Group to synthesize the main contributions and discussions for each of the topical working groups: Astronomy, Astrophysics and Astroparticle Physics; Cosmology; Dark Matter; Neutrinos; Electroweak and Strong Interactions, Higgs physics, Flavour and CP Physics and Beyond the Standard Model Physics; Instrumentation and Computing. This work aims at providing a landscape of existing expertise and capabilities. It will hopefully instruct some recommendations for further development of strategic research infrastructures relevant for future HECAP efforts in the region as well as for a continuous and successful involvement of Latin American HECAP researchers in the global arena.