Troy Magney
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troymagney.bsky.social
Troy Magney
@troymagney.bsky.social
1.2K followers 370 following 17 posts
Plant ecophysiology, ecosystem ecology, tinkering | Plant Optics Lab @ University of Montana | https://magneylab.ucdavis.edu
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troymagney.bsky.social
This was a big collaborative effort and was so fun to put together. Stemming from a FLUXNET workshop we led in 2023. @ameriflux.bsky.social @fluxnetecn.bsky.social
January 23, 2025 at 6:23 PM
troymagney.bsky.social
New Tansley review paper from Zoe Pierrat & friends in @newphyt.bsky.social linking proximal remote sensing with ecosystem fluxes!

Synergies and best practices for hyperspectral reflectance, SIF, thermal, microwave and lidar 🌈🌲🗼🛰️🧪
nph.onlinelibrary.wiley.com/doi/10.1111/...
Overview of proximal remote sensing instruments at a flux tower site. Shown are three eddy-covariance towers with sonic anemometers collecting data to derive ecosystem fluxes. Shown for spectral reflectance and solar-induced fluorescence (SIF) is a hyperspectral sensor with a narrow field-of-view (FOV) and multi-directional scanning capabilities (Sections II.1 and II.2). We also show the direct emission of SIF from the forest canopy (Section II.2). For thermal infrared radiation, we show a fixed thermal camera and thermal radiation coming from the canopy (Section II.3). For microwave, we show two potential arrangements with antenna A receiving direct signals from under open-sky conditions as well as signals that are reflected from the underlying vegetated surface, and antenna B receiving a direct signal that is propagated downward through the vegetation canopy and attenuated by its moisture content (Section II.4). We also show a light detection and ranging (LiDAR) instrument emitting light to get a 3D representation of canopy structure (Section II.5). Above the forest are a drone, aircraft, and satellite to emphasize the potential of proximal remote sensing to complement observations across scales. In the inset plot, we show sample reflectance spectra for vegetation and wet soil and highlight key wavelength ranges for spectral reflectance. We also show typical SIF retrieval windows and LiDAR emission windows. Next to the reflectance spectra, we show sample radiance in the thermal infrared region, with example spectra for warm soil and cool vegetation. Finally, we show key measurement wavelength bands for microwave backscatter.
January 23, 2025 at 6:23 PM
troymagney.bsky.social
Future #climate projections of tree cover suggest the boreal forest is headed for an open state (⬇️🌲in south & ⬆️🌲in north)

But, how will boreal tree cover dynamics influence—and be influenced by—climate feedbacks?

We discuss this in a new commentary @pnas.org. 🧪
www.pnas.org/doi/10.1073/...
Simplified conceptual diagram of potential feedbacks associated with a projected open forest state in the year 2100. The transition to an open forest state is closely tied to feedback processes such as changes in biomass and species composition, disturbance (wildfire, insects, wind), albedo, water availability, and permafrost dynamics
January 14, 2025 at 3:39 PM
troymagney.bsky.social
This commentary was on a recently published paper by Wu et al. (nph.onlinelibrary.wiley.com/doi/10.1111/...) - who use hyperspectral reflectance to predict leaf dark respiration. It outperforms traditional trait-based approaches by a lot.

I re-analyzed some of their data to try to explain why
Subtle differences in hyperspectral reflectance curves from leaves representing a range of physiological conditions. (a) Reflectance data for the mean (50th percentile, black dashed), high (90th percentile, green), and low (10th percentile, purple) Rdark samples from the Wu et al. (2024; doi: 10.1111/nph.20267) dataset, highlighting key traits associated with regions of interest in the visible (400–700 nm), near-infrared (c. 700–1400 nm), and shortwave infrared (c. 1400–2500 nm). (b) The percent difference between high- and low-Rdark samples from the mean, annotated with the direction of observed differences for key traits. The high-Rdark spectra show increased absorption in the chlorophyll (Chl) regions (c. 400–470 and c. 630–670 nm), while the low-Rdark spectra show decreased reflectance centered at 531 nm, a prominent xanthophyll absorption feature. Additionally, there is greater reflectance in the near-infrared region for high-Rdark spectra, suggesting higher leaf thickness and leaf mass per area (LMA), and higher absorption (lower reflectance) in the water absorption features in the shortwave infrared.
December 16, 2024 at 4:31 PM
troymagney.bsky.social
I sadly won't be at #AGU24 this year, but some of our lab members and science will be! 🍃🌈🌎🧪
December 9, 2024 at 2:17 PM
troymagney.bsky.social
Book chapter pre-print on scaling forest ecophysiology using optical techniques. 🍃->🌲🌳->🌎

It was impossible to cover as much as I wanted to, but wanted to share in case anyone has useful feedback, I'd love to hear from you and change accordingly!

essopenarchive.org/users/534071...
November 13, 2024 at 12:48 AM
troymagney.bsky.social
New paper in Ecology! 🌲❄️

"Seasonal timing of fluorescence and photosynthetic yields at needle and canopy scales in evergreen needleleaf forests" by Zoe Pierrat et al.

esajournals.onlinelibrary.wiley.com/doi/10.1002/...

PS I'm going to start using bsky more :)
August 20, 2024 at 5:24 PM
troymagney.bsky.social
Recent install of TSWIFT (Tower-Spectrometer on Wheels Investigating Frequent Timeseries) at Tonzi Ranch - excited to link optical and energy fluxes at this iconic oak savannah woodland site!

@ucdavisplants.bsky.social
February 21, 2024 at 6:39 PM
troymagney.bsky.social
Really excited to share with my small following here this paper that summarizes the last 5 years of our work trying to understand how to track photosynthesis in evergreen forests across scales 🌲🌈

Led by Zoe Pierrat, and published in BioScience!

tinyurl.com/bioscizp
January 9, 2024 at 8:47 PM
troymagney.bsky.social
Looking forward to #AGU23! Come find these great scientists and humans from the Plant Optics Lab

Scientific Program link to our stuff: tinyurl.com/PlantOpticsL...
December 7, 2023 at 3:49 PM