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At least 163 records · Page 9

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DOE OSTI2022

AmeriFlux FLUXNET-1F US-Me2 Metolius mature ponderosa pine

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-Me2 Metolius mature ponderosa pine. This is the FLUXNET version of the carbon flux data for the site US-Me2 Metolius mature ponderosa pine produced by applying the standard ONEFlux (1F) software. Site Description - Site Description before Fire (January, 2002 - August, 2020): The mean stand age is 71 years old and the stand age of the oldest 10% of trees is about 108 years old. This site is one of the Metolius core cluster sites with different age and disturbance classes and part of the AmeriFlux network. The overstory is almost exclusively composed of ponderosa pine trees (Pinus ponderosa Doug. Ex P. Laws) with a few scattered incense cedars (Calocedrus decurrens (Torr.) Florin) and has a peak leaf area index (LAI) of 2.1 m2 m-2. Tree height is relatively homogeneous at about 18 m, and the mean tree density is approximately 339 trees ha-1 (Irvine et al., 2008). The understory is sparse with an LAI of 0.2 m2 m-2 and primarily composed of bitterbrush (Purshia tridentata (Push) DC.) and greenleaf manzanita (Arctostaphylos patula Greene). Soils at the site are sandy (69%/24%/7% sand/silt/clay at 0–0.2 m depth and 66%/27%/7% at 0.2–0.5 m depth, and 54%/ 35%/11% at 0.5–1.0 m depth), freely draining with a soil depth of approximately 1.5 m (Irvine et al., 2008; Law et al., 2001b; Schwarz et al., 2004). Green Ridge Fire: On August 20, 2020, the Green Ridge Fire burned through Us-Me2. The fire was ignited by lightning on August 16th, and grew rapidly to the east over the first few days driven by strong, downslope (westerly) afternoon winds. Fire behavior and observed fire effects were highly heterogeneous due to the localized wind pattern carrying the flaming head of the fire forward, and the efforts being made by suppression resources to contain the fire. The site experienced the full range of fire effects, from <1 m high surface fire that charred litter and duff and only consumed shrubs and herbaceous material to full tree (>15 m) crown fire that consumed 100% of needles, small limbs, and surface fuels at high intensity, leaving only ash and bare soil post-fire. Salvage Logging: From late March to late April 2021, salvage logging by the landowner occurred at the site. Almost all trees within the flux footprint were logged except a small area with lower burn severity, where sap flow and automatic soil respiration measurements are continued since the fire. In August 2022 the primary flux system was moved from the top of the damaged tall tower to a nearby shorter tower centering on the salvage/regenerating footprint.

Hanson, Chad↗

DOE OSTI2022

AmeriFlux FLUXNET-1F US-MOz Missouri Ozark Site

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-MOz Missouri Ozark Site. This is the FLUXNET version of the carbon flux data for the site US-MOz Missouri Ozark Site produced by applying the standard ONEFlux (1F) software. Site Description - The site is located in the University of Missouri Baskett Wildlife Research area, situated in the Ozark region of central Missouri. The site is uniquely located in the ecologically important transitional zone between the central hardwood region and the central grassland region of the US. The land has been publically owned since the 1930s, and is on a land tract that was forested with the same dominant species before settlement in the early 1800s.

Wood, Jeffrey↗

DOE OSTI2022

AmeriFlux FLUXNET-1F US-GLE GLEES

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-GLE GLEES. This is the FLUXNET version of the carbon flux data for the site US-GLE GLEES produced by applying the standard ONEFlux (1F) software. Site Description - The Glacier Lakes Ecosystem Experiments Site (GLEES) site is located on land owned by the U.S. government and managed by US Forest Service as part of the Medicine Bow National Forest. Many of the trees in the immediate vicinity of the site are older than 400 years, inter-dispersed among trees much younger in age. This widespread age distribution is most likely a derivation of one of two scenarios: 1) A widespread stand replacement about 400 years ago followed by a slow replacement; 2) Intermittent random disturbances over the past 400 years (Bradford et al. 2008). A decade long spruce beetle outbreak that peaked in 2008 resulted in the mortality of 85% of the forested basal area. There are a few private land holdings in the area, with scattered uncorked mining claims. Following the establishment of the National Forest, mining was banned and grazing was closed in the early 1990's in the upper portion of the GLEES site. Recreation in the winter, when snow can remain in patches into the summer months, snow mobiling and cross country skiing are popular. During the limited summer, hiking, camping and fishing are common activities. The site is accessible by vehicle only during the summer on Forest Road FDR 317, and in the winter, the tower is only reachable via snowmobile.

Frank, John↗

DOE OSTI2022

AmeriFlux FLUXNET-1F US-Sne Sherman Island Restored Wetland

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-Sne Sherman Island Restored Wetland. This is the FLUXNET version of the carbon flux data for the site US-Sne Sherman Island Restored Wetland produced by applying the standard ONEFlux (1F) software. Site Description - A new restored wetland on the old Sherman Pasture site. The new tower is about 67m northwest (300deg) of the old tower site (US-Snd). On Jan 30, 2020 a temporary tower was set up in the western portion of Sherman Wetland to capture the more vegetated areas and compare with the main tower.

Shortt, Robert↗

DOE OSTI2022

AmeriFlux FLUXNET-1F US-CF2 CAF-LTAR Cook West

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-CF2 CAF-LTAR Cook West. This is the FLUXNET version of the carbon flux data for the site US-CF2 CAF-LTAR Cook West produced by applying the standard ONEFlux (1F) software. Site Description - CF2 has operated since May 2017 at the R.J. Cook Agronomy Farm outside of Pullman, Washington, and monitors the conventionally tilled side of a paired-catchment study that is part of the Longterm Agroecosystem Research (LTAR) site common experiment. CF2 is located in “Cook West,” a field that has been in conventional tillage since prior to 1998 and constitutes the Prevalent treatment of the common experiment. In this case, conventional tillage involves chisel plowing after the winter wheat phase of rotations (approximately every 3-4 years) and occasional harrowing. CF2 is paired with the CF1 tower location in “Cook East,” which has been in no-till since 1998 and represents the Alternative treatment of the common experiment. Both fields are planted in the same crops every year. Cook Agronomy Farm is in the high precipitation agroecological zone of the Columbia Plateau’s dryland cropping region. Crop rotations are wheat-based and include winter wheat, spring wheat, chickpea, spring canola, and winter peas. Wheat is the principal cash crop, with other crops grown in rotation for diversity, nutrient, and pest management. Soils are predominantly silt loam texture Mollisols in the Palouse, Thatuna, Naff soil series. The CF2 tower replaced US-RC2, which operated 2012-2016 in a neighboring field that was also conventionally tilled. CF2 and RC2 have distinct footprints, aspects, and soil series compositions.

Huggins, Dave↗

DOE OSTI2022

AmeriFlux FLUXNET-1F US-Jo1 Jornada Experimental Range Bajada Site

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-Jo1 Jornada Experimental Range Bajada Site. This is the FLUXNET version of the carbon flux data for the site US-Jo1 Jornada Experimental Range Bajada Site produced by applying the standard ONEFlux (1F) software. Site Description - The Jornada Basin Experimental Range (JER) covers 783 km2 in the La Jornada del Muerto Plain of the northern Chihuahuan Desert and is located 20km of Las Cruces, NM. Extensive livestock grazing at the JER and througout the US Southwest was coincident with large-scale grassland deterioration and transition to shrubland begining in the 1800s. The JER was established n 1912 to investigate these rangeland changes and has since become a central location for understanding dryland ecology. This flux tower monitors CO2 and H2O dynamics in a representative shrubland on the piedmont slope (bajada) of the San Andreas mountains. The dominant shrubs are evergreen Larrea tridentata (Creosote) and winter-deciduous Prosopis glandulosa (Honey Mesquite). Other cover types include Flourensia cernua (tarbush) and patchy occurences of the grasses Muhlenbergia porteri (Bush Muhly) and Dasyochloa pulchella (Fluff Grass). The site is occasionally visited by stray domestic cattle, free-ranging introduced Oryx, and other native herbivores (Jack Rabbits, Desert Pronghorn). Soils at the site are Ustic Calciargids and parent material consists of limestone, other sedimentary rock, and some igneous rock. Virtual Site Visit: https://youtu.be/v1uJCKuicqs

Tweedie, Craig↗

DOE OSTI2023

AmeriFlux FLUXNET-1F US-ALQ Allequash Creek Site

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-ALQ Allequash Creek Site. This is the FLUXNET version of the carbon flux data for the site US-ALQ Allequash Creek Site produced by applying the standard ONEFlux (1F) software. Site Description - From Turner et al (2019): The 32 ha fen wetland is situated in Trout Lake Basin in northern WI (46.030759,−89.606730). It is part of the National Science Foundation’s North Temperate Lakes Long-Term Ecological Research (NTL-LTER) as formerly as part of the US Geological Survey’s Water, Energy and Biogeochemical Budgets Program (WEBB) Trout Lake site. The soil comprises outwash sand and gravel atop crystalline bedrock. Due to the glacial outwash, the soil is highly conductive and promotes groundwater discharge to the nearby creek. A headwater stream, Allequash Creek, flows from the southeast to the northwest through the fen. The eddy covariance flux tower is located along the stream which is surrounded by tree stands to the northeast and southwest that create a “valley” and cause channelized flow in the direction of the stream.

Desai, Ankur↗

DOE OSTI2023

AmeriFlux FLUXNET-1F US-Me6 Metolius Young Pine Burn

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-Me6 Metolius Young Pine Burn. This is the FLUXNET version of the carbon flux data for the site US-Me6 Metolius Young Pine Burn produced by applying the standard ONEFlux (1F) software. Site Description - The study site is located east of the Cascade mountains, near Sisters, Central Oregon and is part of the Metolius cluster sites with different age and disturbance classes within the AmeriFlux network. After a severe fire in 1979, the site was salvage logged, was acquired by the US Forest Service land and re-forested in 1990. The dominant overstory vegetation are 20-year old ponderosa pine trees with an average height of 5.2 +/- 1.1 m. The season maximum overstory half-sided LAI was 0.6 m2 m-2 in 2010. Tree density is low, with ca. 162 trees ha-1.

Hanson, Chad↗

DOE OSTI2023

AmeriFlux FLUXNET-1F US-SRG Santa Rita Grassland

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-SRG Santa Rita Grassland. This is the FLUXNET version of the carbon flux data for the site US-SRG Santa Rita Grassland produced by applying the standard ONEFlux (1F) software. Site Description - Semidesert C4 grassland, lies in Pasture 1 on the Santa Rita Experimental Range. This is the companion site for US-SRM, but has much less mesquite encroachment.

Scott, Russell↗

DOE OSTI2023

AmeriFlux FLUXNET-1F US-Vcm Valles Caldera Mixed Conifer

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-Vcm Valles Caldera Mixed Conifer. This is the FLUXNET version of the carbon flux data for the site US-Vcm Valles Caldera Mixed Conifer produced by applying the standard ONEFlux (1F) software. Site Description - The Valles Caldera Mixed Conifer site is located in the 1200 km2 Jemez River basin in north-central New Mexico. Common to elevations ranging from 3040 to 2740 m in the region, the mixed conifer stand, within the entirety of the tower footprint in all directions, provides an excellent setting for studying the seasonal interaction between snow and vegetation. In late May 2013, this site experienced a stand-replacing wildfire. It was a very hot fire that killed every single tree, and burned off a lot of surface organic matter. We have a big gap in fluxes from May 2013- Jan 2014. We were not even allowed in to the site until Oct 2013, and it took us 2-3 months to clean up the debris, remove burned infrastructure, have the tower structure assessed, and resinstrument the site.

Litvak, Marcy↗

DOE OSTI2024

AmeriFlux FLUXNET-1F US-ASM USSL San Joaquin Valley Almond Medium Salinity

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-ASM USSL San Joaquin Valley Almond Medium Salinity. This is the FLUXNET version of the carbon flux data for the site US-ASM USSL San Joaquin Valley Almond Medium Salinity produced by applying the standard ONEFlux (1F) software. Site Description - almond orchard in San Joaquin Valley. Different water source and water quality than adjacent site US-SAH

Anderson, Ray G.↗

DOE OSTI2025

AmeriFlux FLUXNET-1F US-GL1 Stannard Rock

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-GL1 Stannard Rock. This is the FLUXNET version of the carbon flux data for the site US-GL1 Stannard Rock produced by applying the standard ONEFlux (1F) software. Site Description - Stannard Rock is located 39 km from the nearest shore (Keweenaw Peninsula) in Lake Superior, 44 miles NNE of Marquette, Michigan, and 24 miles ESE of Manitou Island. The site is located on the historic Stannard Rock Lighthouse, which was completed in 1882. Eddy covariance instrumentation was installed in 2008 by a network of scientists from both US and Canada, eventually to be called the Great Lakes Evaporation Network (GLEN). The intent of GLEN has been to provide observations of over-lake meteorology and evaporation, improve forecasting of Great Lakes water levels, and support a wide variety of stakeholders, including the National Weather Service (NWS), Environment and Climate Change Canada, National Oceanic and Atmospheric Administration, U.S. Coast Guard, recreational boaters and commercial shipping, emergency management officials, and the Great Lakes research community. The eddy covariance station along with other ancillary meteorological instrumentation is located at an approximate elevation of 39.2 meters above mean lake water level. Meteorological data from the lighthouse are sent to the National Data Buoy Center, where they can be viewed in real-time at http://www.ndbc.noaa.gov/station_page.php?station=stdm4 Uncorrected half-hour fluxes were computed directly on the logger using a 30-minute block averaging period as high-frequency data were not available. The half hour flux measurements downloaded from the datalogger were post-processed with the following filters and corrections. Latent and sensible heat and carbon dioxide fluxes were corrected with 2-D coordinate rotation. Although the primary objective of data collection at Stannard Rock was to quantify the evaporative flux, additional preliminary measurements of the carbon dioxide concentration and flux from the LI-7500 are also included in this dataset but it is advised to use the carbon data with caution. Carbon data reported in this dataset includes turbulent fluxes of CO2 with no storage correction (FC, µmol m-2 s-1) and CO2 density in mole fraction of wet air (CO2), which was originally output on the datalogger as average CO2 density (mg m-2 s-1) and converted into µmol mol-1 using air temperature and pressure in post-processing. Webb, Pearman, and Leuning terms were applied to account for density fluctuations for water vapor and CO2. Sonic path length, high-frequency attenuation and sensor separation were accounted for according to Horst and Massman, and the oxygen absorption correction for the KH2O hygrometer was also applied. Latent and sensible heat fluxes were assumed to be unrealistic above an absolute value of 1000 W m-2 and were removed. Both carbon flux (FC) and carbon dioxide mole fraction in wet air (CO2) and were assumed to be unrealistic above 1000 µmol m-2 s-1 and 1000 µmol mol-1 respectively. Spikes in latent and sensible heat and carbon fluxes and densities (often due to periods of precipitation) were identified by computing the mean and standard deviation over a moving, overlapping window of 336 half-hours (7 days), similar to Shao et al., and were removed when the flux was more than 1.5 standard deviations from the moving window’s mean. While Vickers and Mahrt use a threshold of 3.5 standard deviations from the mean, a conservative value of 1.5 was chosen due to the noisy nature of over-lake data at this particular site. This process was repeated twice for latent and sensible heat, and carbon dioxide fluxes and densities and therefore it is possible that some real, realistic data was filtered out in this process. No detrending was performed. As per AmeriFlux standards, no friction velocity (USTAR, m s-1) filtering was performed.

Spence, Chris [Environment and Climate Change Cana↗

DOE OSTI2026

AmeriFlux FLUXNET-1F US-Los Lost Creek

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-Los Lost Creek. This is the FLUXNET version of the carbon flux data for the site US-Los Lost Creek produced by applying the standard ONEFlux (1F) software. Site Description - Shrub wetland site, chosen to be representative of the wetlands within the US-PFa tall tower flux footprint. This is a deciduous shrub wetland. Coniferous and grassy stands also exist within the fux footprint. Solar power. The site has excellent micrometeorological characteristics.

Desai, Ankur [University of Wisconsin]↗

DOE OSTI2026

AmeriFlux FLUXNET-1F US-RC2 Cook Agronomy Farm - Conventional Till

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-RC2 Cook Agronomy Farm - Conventional Till. This is the FLUXNET version of the carbon flux data for the site US-RC2 Cook Agronomy Farm - Conventional Till produced by applying the standard ONEFlux (1F) software. Site Description - RC2 operated from 2013-2016 at the R.J. Cook Agronomy Farm, as part of a cluster of 5 towers (RC1 to RC5) operated for the Regional Approaches to Climate Change (REACCH) USDA-supported research project. The tower predates the Longterm Agroecosystem Research (LTAR) site common experiment, which was established in nearby fields at the Cook Agronomy Farm in 2017. Cook Agronomy Farm is in the high-precipitation agroecological zone of the Columbia Plateau’s dryland cropping region. Wheat-based crop rotations are grown annually. RC2 had conventional tillage management (reduced-till) since at least 1998. It was contrasted with RC1, which had no-till management over the same time period. RC2 captured the same tillage practices as the US-CF2 site established in 2017 as part of LTAR common experiment. However, the towers have distinct footprints, aspects, and soil series composition.

Chi, Jinshu [The Hong Kong University of Science a↗

DOE OSTI2026

AmeriFlux FLUXNET-1F US-RC1 Cook Agronomy Farm - No Till

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-RC1 Cook Agronomy Farm - No Till. This is the FLUXNET version of the carbon flux data for the site US-RC1 Cook Agronomy Farm - No Till produced by applying the standard ONEFlux (1F) software. Site Description - RC1 operated from 2013-2016 at the R.J. Cook Agronomy Farm, as part of a cluster of 5 towers (RC1 to RC5) operated for the Regional Approaches to Climate Change (REACCH) USDA-supported research project. The tower predates the Longterm Agroecosystem Research (LTAR) site common experiment, which was established in nearby fields at the Cook Agronomy Farm in 2017. Cook Agronomy Farm is in the high precipitation agroecological zone of the Columbia Plateau’s dryland cropping region. Wheat-based crop rotations are grown on an annual planting schedule. RC1 was in no-till management since 1998, and was contrasted with RC2, which had conventional, reduced-tillage management. RC1 captured the same tillage practices as the US-CF1 site established in 2017 as part of LTAR common experiment. However, the towers have distinct footprints, aspects, and soil series composition.

Chi, Jinshu [The Hong Kong University of Science a↗

DOE OSTI2026

AmeriFlux FLUXNET-1F US-UiC University of Illinois Maize-Soy

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-UiC University of Illinois Maize-Soy. This is the FLUXNET version of the carbon flux data for the site US-UiC University of Illinois Maize-Soy produced by applying the standard ONEFlux (1F) software. Site Description - Agricultural field planted with maize in a three year rotation with soy (maize-maize-soy). The first soy rotation year was 2010. This field is typically planted in May and harvested in October. This site is located at an experimental farm approximately 2 miles south of the University of Illinois at Urbana Champaign and is colocated with (500-1000m distance) all other Us-Ui sites.

Bernacchi, Carl J [USDA/ARS]↗

DOE OSTI2026

AmeriFlux FLUXNET-1F US-UiE University of Illinois Sorghum-Soy

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-UiE University of Illinois Sorghum-Soy. This is the FLUXNET version of the carbon flux data for the site US-UiE University of Illinois Sorghum-Soy produced by applying the standard ONEFlux (1F) software. Site Description - Agricultural field planted with photoperiod-sensitive ("energy") sorghum bicolor in a three year rotation with soy (sorghum-sorghum-soy). The first soy rotation was in 2019. This field is typically planted in May and harvested for biomass (sorghum) or grain (soy) in October. This site is located at an experimental farm approximately 2 miles south of the University of Illinois at Urbana Champaign and is colocated with (500-1000m distance) all other Us-Ui sites.

Bernacchi, Carl J [Department of Crop Sciences, Un↗

DOE OSTI2026

AmeriFlux FLUXNET-1F US-WCr Willow Creek

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-WCr Willow Creek. This is the FLUXNET version of the carbon flux data for the site US-WCr Willow Creek produced by applying the standard ONEFlux (1F) software. Site Description - Upland decduous broadleaf forest. Mainly sugar maple, also basswood. Uniform stand atop a very modest hill. Clearcut approximately 80 years ago. Chosen to be representative of the upland deciduous broadleaf forests within the US-PFa tall tower flux footprint. It appears to be more heavily forested and more productive than most of the upland deciduous broadleaf forests in the region. Extensive forest thinning in 2013-2014 removed 30% of overstory biomass in flux footprint.

Desai, Ankur↗