- Himalayan Cedars in the Mist: The new TLSIIG header image is thanks to Michael Schaefer and his recent blog post at the Oz DWEL Blogspot. According to the post, it is produced from a scan acquired at the Australian National Arboretum in Canberra with the Dual Wavelength Echidna Lidar and uses intensity information recorded from the 1556 nm laser. Pictured is a stand of Himalayan cedars — with intensities fading to white with distance, the trees seem to disappear into a misty world.
TLSIIG at AGU 2016
- Abstract submissions have closed and the program committee is now considering posters and presentations at the Fall Meeting of the American Geophysical Union in San Francisco, 12-16 December. If you’re headed that way, be sure to look up AGU Biogeosciences Session #12829: Advancing understanding of ecosystem structure and function through remote sensing, organized by TLSRCN participants Chris Gough and Brady Hardiman, for some of the latest developments in TLS applications.
Quantitative Structure Model (QSM) Papers Online Here
- Have you been meaning to catch up on your reading about QSM? Look no farther than our new page of QSM papers with links to pdfs!
New Posts on TLSIIG Member Sites and Blogs
Click on the links at the left to view the news at the sites below:
- Australian DWEL Blogspot: “Tumbarumba!” Not a pirate’s curse, but the location of a TERN supersite with tower in a wet sclerophyll forest of 40-m eucalypts in southeastern New South Wales. On the scene was the Tumba Laser Scanning Team, with TLSIGers Michael Schaefer, Will Woodgate, and five others, for a week of scanning with the DWEL, Riegl VZ-400, CBL, and two Zebedee scanners. Wow! The goal is to merge the tower’s hyperspectral imager with the scans. Read more at the site.
- Mat Disney’s Blogspot: Back from Gabon, Mat’s group has finished putting together the Mondah plots and is working to link the trees in the scan with the trees on the ground. Take a look at their Zebedee data, too!
- QFo Finland: Tampere Institute of Technology, Finland, held a groundbreaking workshop focused on Tree Data and Modeling, June 7-9. Participants were drawn from laser scanning, functional-structural plant modelling, forest science and mathematical modeling. Visit the workshop site for more info — a meeting report by the organizers is on the way.
- UMass CBL Lidar: Drop in for a new look with lots of photos of the CBL deployed from tropical forest to salt marshes. A tour de force for the “little lidar that could!”
- The SALCA Diaries: TLSIIG members Mark Danson, Mat Disney, Rachel Gaulton, and Crystal Schaaf have won support from the Royal Society to lead a Theo Murphy International Scientific Meeting to be held at The Society’s Chicheley Hall in the UK in February 2017. The subject will be, “The terrestrial laser scanning revolution in forest ecology”. Sixteen invited speakers from the UK, US, Finland, Netherlands, and Australia. A good time will be had by all!
TLS Research Coordination Network
- The TLSRCN web site opened in Fall 2015, to document RCN activities and allow participants to exchange information. Have a look, and if you are interested, see the last paragraph of the Welcome page to apply to join.
- Tired of worrying about using those stock values for the proportion of woody area (α) in the PAI to estimate the LAI from hemiphotos? Take heart — Will Woodgate and friends have a new method for retrieving α from classified imagery or scanner data that works really well. Their new paper in Agricultural and Forest Meteorology provides the details.
- Lambertian leaves? Think again. A new paper by Sanna Kaasalainen and colleagues at QFo Finland uses their hyperspectral lidar to show that leaves do, in fact, have a strong specular component to lidar reflectance. And, the specularity is wavelength dependent — so spectral indexes or even spectral ratios are angle-dependent, too. Hmmm….
- Can TLS actually distinguish between tree species? Apparently so, if you have the right classification features based on TSL structural measurements. Yi Lin and Martin Herold show how in their new paper in Agricultural and Forest Meterology.
- Road trip! Attaching a SICK lidar and an active optical sensor to their 4-wheel drive SUV, Michael Schaefer and Dave Lamb recently cruised through a tall fescue pasture, mapping biomass from height and NDVI. You can read how they did it in their recent article in Remote Sensing.
- Who knew? A five-parameter model for calibrating the Dual Waveform Echidna Lidar? That’s what it took to cover the range from 1 m and beyond, thanks to telescopic effects that decrease the signal from midrange (10-12 m) toward the instrument and Lambert’s Law, which decreases the signal from midrange to far range. See the fit in a new Sensors article by Zhan Li et al.
- Tired of trying to make sense of those intensities that come with the hits in the point cloud? Maybe you should try some calibration. Lucy Schofield’s new paper in Remote Sensing Letters on the calibration of the SALCA bispectral TLS shows how to turn those messy DNs into apparent reflectances, which are much neater. Just use a neural net!
- Trying to remember what that AGU talk was last fall on dual-wavelength TLS? There were actually several — just load the AGU 2015 Meeting page and use the links to the sessions and abstracts.