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Pederson, Taylor

Publications and source records attributed to Pederson, Taylor.

AmeriFlux FLUXNET-1F US-UiA University of Illinois Switchgrass

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-UiA University of Illinois Switchgrass. This is the FLUXNET version of the carbon flux data for the site US-UiA University of Illinois Switchgrass produced by applying the standard ONEFlux (1F) software. Site Description - Field was treated with Potash, lime and diammonium phosphate before planting. Herbicide application included 2,4-D for 2008, 2009. 56 kg/ha nitrogen applied in 2010, 2011, 2012, 2013, 2014, 2016. Measurements were suspended on June 14, 2016 and resumed on May 28, 2024.

Bernacchi, Carl↗

AmeriFlux FLUXNET-1F US-UiB University of Illinois Miscanthus

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-UiB University of Illinois Miscanthus. This is the FLUXNET version of the carbon flux data for the site US-UiB University of Illinois Miscanthus produced by applying the standard ONEFlux (1F) software. Site Description - Diammonium phosphate, potash & lime fertilizer applied before planting in 2008. Prowl & 2,4-D herbicide used. 2,4-D & accent herbicide applied in 2009. No fertilizer applied. Bicep herbicide applied in 2010 & 2011. 56 kg/ha nitrogen applied in 2014, 2015 & 2016. 45 kg/ha nitrogen applied in 2017.

Bernacchi, Carl J [USDA/ARS]↗

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]↗

AmeriFlux FLUXNET-1F US-UiD University of Illinois Restored Native Prairie

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-UiD University of Illinois Restored Native Prairie. This is the FLUXNET version of the carbon flux data for the site US-UiD University of Illinois Restored Native Prairie produced by applying the standard ONEFlux (1F) software. Site Description - Site harvested annually with a mower during winters starting 2009. No fertilizer was applied, and not irrigated. Measurements were paused on March 23, 2016 and resumed in June 2024.

Bernacchi, Carl↗

AmeriFlux US-UiD University of Illinois Restored Native Prairie

This is the AmeriFlux version of the carbon flux data for the site US-UiD University of Illinois Restored Native Prairie. Site Description - Site harvested annually with a mower during winters starting 2009. No fertilizer was applied, and not irrigated. Measurements were paused on March 23, 2016 and resumed in June 2024.

Bernacchi, Carl↗

AmeriFlux US-UiB University of Illinois Miscanthus

This is the AmeriFlux version of the carbon flux data for the site US-UiB University of Illinois Miscanthus. Site Description - Diammonium phosphate, potash & lime fertilizer applied before planting in 2008. Prowl & 2,4-D herbicide used. 2,4-D & accent herbicide applied in 2009. No fertilizer applied. Bicep herbicide applied in 2010 & 2011. 56 kg/ha nitrogen applied in 2014, 2015 & 2016. 45 kg/ha nitrogen applied in 2017.

Bernacchi, Carl J↗

AmeriFlux US-UiC University of Illinois Maize-Soy

This is the AmeriFlux version of the carbon flux data for the site US-UiC University of Illinois Maize-Soy. 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↗

Understanding Growth Dynamics and Yield Prediction of Sorghum Using High Temporal Resolution UAV Imagery Time Series and Machine Learning

Unmanned aerial vehicles (UAV) carrying multispectral cameras are increasingly being used for high-throughput phenotyping (HTP) of above-ground traits of crops to study genetic diversity, resource use efficiency and responses to abiotic or biotic stresses. There is significant unexplored potential for repeated data collection through a field season to reveal information on the rates of growth and provide predictions of the final yield. Generating such information early in the season would create opportunities for more efficient in-depth phenotyping and germplasm selection. This study tested the use of high-resolution time-series imagery (5 or 10 sampling dates) to understand the relationships between growth dynamics, temporal resolution and end-of-season above-ground biomass (AGB) in 869 diverse accessions of highly productive (mean AGB = 23.4 Mg/Ha), photoperiod sensitive sorghum. Canopy surface height (CSM), ground cover (GC), and five common spectral indices were considered as features of the crop phenotype. Spline curve fitting was used to integrate data from single flights into continuous time courses. Random Forest was used to predict end-of-season AGB from aerial imagery, and to identify the most informative variables driving predictions. Improved prediction of end-of-season AGB (RMSE reduction of 0.24 Mg/Ha) was achieved earlier in the growing season (10 to 20 days) by leveraging early- and mid-season measurement of the rate of change of geometric and spectral features. Early in the season, dynamic traits describing the rates of change of CSM and GC predicted end-of-season AGB best. Late in the season, CSM on a given date was the most influential predictor of end-of-season AGB. The power to predict end-of-season AGB was greatest at 50 days after planting, accounting for 63% of variance across this very diverse germplasm collection with modest error (RMSE 1.8 Mg/ha). End-of-season AGB could be predicted equally well when spline fitting was performed on data collected from five flights versus 10 flights over the growing season. This demonstrates a more valuable and efficient approach to using UAVs for HTP, while also proposing strategies to add further value.

54 ENVIRONMENTAL SCIENCES↗

Plot-level rapid screening for photosynthetic parameters using proximal hyperspectral imaging

Abstract Photosynthesis is currently measured using time-laborious and/or destructive methods which slows research and breeding efforts to identify crop germplasm with higher photosynthetic capacities. We present a plot-level screening tool for quantification of photosynthetic parameters and pigment contents that utilizes hyperspectral reflectance from sunlit leaf pixels collected from a plot (~2 m×2 m) in <1 min. Using field-grown Nicotiana tabacum with genetically altered photosynthetic pathways over two growing seasons (2017 and 2018), we built predictive models for eight photosynthetic parameters and pigment traits. Using partial least squares regression (PLSR) analysis of plot-level sunlit vegetative reflectance pixels from a single visible near infra-red (VNIR) (400–900 nm) hyperspectral camera, we predict maximum carboxylation rate of Rubisco (Vc,max, R2=0.79) maximum electron transport rate in given conditions (J1800, R2=0.59), maximal light-saturated photosynthesis (Pmax, R2=0.54), chlorophyll content (R2=0.87), the Chl a/b ratio (R2=0.63), carbon content (R2=0.47), and nitrogen content (R2=0.49). Model predictions did not improve when using two cameras spanning 400–1800 nm, suggesting a robust, widely applicable and more ‘cost-effective’ pipeline requiring only a single VNIR camera. The analysis pipeline and methods can be used in any cropping system with modified species-specific PLSR analysis to offer a high-throughput field phenotyping screening for germplasm with improved photosynthetic performance in field trials.

59 BASIC BIOLOGICAL SCIENCES↗