Participants

Interest Groups

Telecons

All-Hands Telecon, January 22, 2018

All-Hands Telecon, May 17, 2018

All-Hands Telecon, July 18, 2018

  • Agenda
  • Notes
  • Recording unavailable, technical failure

All-Hands Telecon, February 20, 2019

All-Hands Telecon, September 11, 2019

All-Hands Telecon, November 5, 2019

Harvard Forest Calibration Activity Telecons

RCN Meeting at SilviLaser, 1–2 October, 2015

Tree Data and Modeling Workshop, Tampere University of Technology, 7–9 June, 2016

GFOI R&D and GOFC-GOLD Land Cover Science Meeting, The Hague, 31 October – 4 November, 2016

TLS Workshop at Ecological Society of Australia Meeting, 2 December 2016, Fremantle, Western Australia

  • See Google Drive folder of materials, prepared by University of Queensland, DSITI, CSIRO researchers

The Royal Society Theo Murphy Meeting, The Terrestrial Laser Scanning Revolution in Forest Ecology, 27-28 February, Chicheley Hall, Buckinghamshire, England

  • Royal Society Web Page for the meeting, including agenda, abstracts of talks, information about speakers, and recordings of talks
  • Special issue of Interface Focus, “The Terrestrial Laser Scanning Revolution in Forest Ecology”, with papers submitted by meeting participants. A three-page

    Meeting Report V.1.4
    TLS RCN Meeting and Workshop
    Following SilviLaser 2015, Geospatial Week
    La Grande Motte, FR
    1–2 October 2015

    Thursday, October 1

    Welcome and Review of Agenda – Alan Strahler

    Activity Reports (Sessions 1 and 2)

    • Boston U.: Alan Strahler
      • The power of NSF DWEL’s lasers have been significantly increased, which should improve future point clouds and PAI retrieval.
      • Zhan Li’s dissertation, as per SilviLaser presentations: Calibration to apparent reflectance completed; a spatial-spectral classification algorithm nicely separates leaves from woody and ground hits, providing separate LAI and Woody AI profiles. Also, QSM structures show lower variance with leaf hits removed.
    • UMass Boston: Crystal Schaaf
      • Scanning with the CBL at La Selva (Costa Rica) tropical forest; Harvard Forest (photosynthesis fluorescence, wolly adelgid infestation); Plum Island salt marsh (w/ Landsat, GLiHT) and Nantucket salt marsh; California savannas (w/ Susan Ustin); urban trees (w/ Lucy Hutyra); possible simulated ice storm damage at Hubbard Brook; possible La Selva return.
      • Multiple height CBL scanning for better crown delineation; atypical structures (root buttresses, mangrove prop roots); merging CBL and DWEL scans; GEDI connection.
    • CSIRO: Michael Schaefer
      • DWEL scanning at AusCover TERN supersites (3 of 10); separation of wood and foliage profiles at Tumbarumba.
      • Forest growth at ACT Arboretum, DWEL and Zebedee, 5 forest types; growth apparent in point clouds and PAI profiles; Zebedee point clouds denser, less occlusion; year 1 and year 2 heights very similar.
      • Viticulture scanning to monitor grape development, DWEL, CBL, Zebedee, “Grover” SICK side scanner on trolley. CBL doing very well; Zebedee coarser resolution; DWEL NDVI shows grape bunches better.
      • Rangeland biomass project, seeking grass cover and biomass from height/volume from CBL; lots of ground and satellite measurements for support.
    • UQ/DSITI: John Armston
      • Using 3 instruments: Riegl VZ400, CBL-2, Vegnet almucantar scanner; acquiring standardized plots through JRSRP and TERN.
      • Developing open source software, Pylidar and SPDLib for TLS/ALS, combining waveform and discrete-return.
      • Looking at cheap PhotoPanorama measurement of structure (DBH, count density, basal area) vs. Riegl TLS; designing new veg structure site index of “biocondition” (Jasmine Muir Ph.D.).
      • Vegnet PAI and profile compares well with Riegl; provides temporal trend.
      • Other TLS apps: gully erosion; beach erosion and veg dynamics.
    • Beijing Normal U.: Yiming Chen
      • Developing new two-step multiple-scan registration method for Riegl using 1 reflector between every 2 scans; testing in open larch/white birch stand.
      • Uses coarse registration from backsight of most recent instrument position; fine registration extracts stem centers and matches them in multiple scans.
      • Working on improvements and possibly use of intensity info, extraction of LAD.
    • UCL: Mat Disney
      • TLS activities: Riegl VZ400, biomass, structure, QSMs, RT, EO++.
      • Gabon, 2013, Riegl vs allometry, 700 trees, Brazil 2014 transect, dense veg, multiple scan registration, BAAD 2015, allometry testing.
      • Alice Holt destructive sampling, QSM biomass validation; Wytham Woods, 376 scans, 6 ha; Kew Gardens giant bonsais.
      • Branch size/shape, scaling across continental environments.
    • Salford: Mark Danson, Lucy Schofield
      • SALCA: data processing, calibration; validation; 4D phenology.
      • Apparent reflectance using neural net calibration; single tree LAI validation at Alice Holt; tree condition monitoring of isolated paddock oaks.
      • SALCA diaries blog documents activities.
      • Royal Society TSL Meeting application (see Governance Issues, Supplementary Support).
    • Newcastle: Rachel Gaulton
      • Vegetation structure and dynamics, plot to landscape; veg health, plant moisture content; ground-based and UAV validation of satellite imagery; sensor development and calibration (SALCA).
      • Dual wavelength TLS at leaf, canopy scales.
      • Field work: Brisbane, SALCA NVI vs. ASD spectrometer vs. lab EWT; ASD bark and moisture. Alice Holt: ASD leaves, bark by trunk and branch size. Aberfoyle red-band needle blight, UAV thermal and TLS.
      • Hedgerow structure from TLS, Zeb-1, Leica P20, SALCA; willow bioenergy crop biomass from thermal UAV, airborne hyperspectral, TLS, hemiphotos.
      • Future: More Brisbane, Alice Holt ASD-TLS; TLS EWT vs. airborne hyperspectral, UAV thermal at Aberfoyle; UAV lidar for bioenergy crop survey; new structural params in agri-environments; permanent plots in Newcastle U. woodland.
    • FGI: Sanna Kaasalainen
      • Hyperspectral lidar progress:
      • Temporal monitoring, green-up to brown, lab tree, study in press, Biogeosciences.
      • New sensor, higher output, better SNR, distance calibration; effect of focus on intensity.
      • Target identification from 8 bands; leaf backscattering, NDVI, vs. incidence angle.
    • Gent: Sruthi Parvathi, Hans Verbeeck
      • Studying lianas in tropical forests re: climate change and increased abundance; effect on carbon balance.
      • Riegl VZ-400 to measure vertical canopy distribution; 3-D liana vs. tree separation algorithms.
      • 4 study sites, Panama, Brazil, French Guiana; liana removal plots, infestation gradient; plot scans.
    • Exeter/U. Maryland: Steve Hancock
      • Return intensity paper now out; RSE 164: 208-224, 2015
      • Urban BESS (Biodiversity and Ecosystem Service Sustainability) project, UK biomes: field data; ALS + airborne hyperspectral makes land cover 4-class map, tall/short and veg/nonveg.
      • ALS Signal processing: modeling actual profile, visible profile, pulsed profile, measured waveform; denoise, model system pulse, correct attenuation.
      • TLS: Riegl VZ-400 point cloud, process for partial hits, attenuation; generate ALS waveform, compare with observed ALS foliage profile and ALS deconvolved voxel space.
      • SALCA activities: calibration from Cockle Park using math model; intensity and NDI with leaf incidence angle in lab.
      • GEDI ALS/TLS: Optimization, noise tracking, gap correction.
    • RIT: Martin van Leeuwen
      • Dave Kelbe’s bi- and multiscan marker-free registration (Ph.D. thesis): view-invariant tie points at intersections of tree stems and terrain models; SVD for rigid transformation, RANSAC to evaluate correspondences; pairwise, then best weighted average for multiple scans.
      • Pairwise, in press for TGARS; Multiple, in review, RSE.
      • Virtual scenes, clumping simulations: simulation of 3-D lidar metrics and correlation with simulated TRAC data.
      • Ray tracing for GPP partitioning of photosynthesis; leaf spectra; time series analysis; test 0.5 ha, Hawaiian forest.
    • Virginia Commonwealth U.: EAGER-NEON Project: (Alan presenting for Chris Gough)
      • New EAGER-NEON project, PIs Chris Gough, Brady Hardiman, Bob Fahey: Is canopy structural complexity (CSC) a global predictor of primary production; use >10 NEON eastern forest sites to determine.
      • CSC prediction of NPP in temperate forest ecosystems; underlying mechanisms.
      • Use portable canopy lidar, vertical distribution of veg along transect sites; correlating NPP and CSC measures, e.g,, rugosity.
    • Wageningen U.: Avaro Lau, Jose Tanago
      • Alvaro, Jose + Martin Herold, Harm Bartholomeus, Jan Verbesselt; instruments Riegl VZ-400, Zebedee, UAV w/ hyperspectral camera.
      • Prior TLS research: tree metrics, forest structure, biomass w/ QSM, PAI time series, urban trees, tomato 3-D lab growth.
      • Present research: QSM biomass, allometry: Gabon, Peru, Indonesia, Guyana Ethiopia, Ghana; Selective logging in tropical forest; tree architecture, scaling; PAI time seris, Riegl, Vegnet, satellite; Forest structure-insect biodiversity; ESA calibration with UCL.
      • TLS data available, w/ others such as Rapid eye; field spectrometer, UAV hyperspectral, ALS, Vegnet.
    • Zurich: Felix Morsdorf
      • 3D VegLab: TLS scanning of forest; branches and stems manually digitized from single range images, fused with different viewpoints; shoot-level reconstructions.
      • TLS scanning with Riegl VZ-1000, tropical forests; voxel-based occlusion mapping; monitoring debris flow motion; Borneo TLS campaign 10/2015 (Fabian Schneider).
      • Validation: ALS and TLS hard to validate; use physical models and virtual sensors to test structure retrieval methods (Meinrad Abegg).

    Interest Group Reports: Reports and Discussion

    • IG1 Instrument Development: (Crystal Schaaf, Sanna Kaasalainen)
      • Ideal scanner: Multispectral, highly portable, rapid scanning, low cost.
      • Laser scanning developing very rapidly and becoming ubiquitous.
      • Instrument reports:
        • DWELs: Calibration, refinement and power upgrades continue.
        • SALCA: Beam alignment, temperature-power issues, calibration issues resolved.
        • CBL: Calibration, refinement, accuracy assessments underway.
        • Riegl VZ400 at UCL: Multiple deployments, from Wytham Woods to French Guiana and Ghana (with WUR).
        • Hyperspectral/selectable multispectral: (see Sanna activities).
      • Vendor news: Zeb-1 backpack; Riegl VUX-1 UAV (e.g., Jim Kellner, Brown); UAV Lidar + multispectral photog (Ascending Technologies); 3-channel ALS (Optec Titan).
      • 2D scanners: Riegl VUX-1 for UAV; SICK LMS151(on CBL1, 2); Hokuyo UTM30LX-UW (Zebedee).
      • 2D+ scanners: YelloScan, $$$; Velodyne VLP-16 (“Puck”), $.
      • Missing capabilities: no dual/multiple/hyperspectral wavelengths; no green; no full waveform end to end; nothing <5K USD.
    • IG2 Data Preprocessing and Analysis: (John Armston)
      • Scope: Standardized scans (for AGB); intercomparable, calibrated, gridded, auto registered point clouds and attributes; software tools; data and management for RCN activities.
      • Interscan registration is critical need, esp. reflectorless; methods to test and assess registration accuracy needed.
      • Calibration: Panel sharing; TLSIIG cal paper, apparent reflectance.
      • File formats: Need dissemination and working, open formats.
      • TLS processing systems: individual workflows; open source software: Pylidar, point cloud library.
      • Visualization tools: Sketchfab, potree (github).
      • Framework for standard processing levels and data products .
    • IG3 Algorithms for Information Extraction (Steve Hancock)
      • Scope: Methods: Traditional, QSM, RT, leaf scale spectral indexes.
      • Issues: Common: Preprocessing; registration; leaf from wood; occlusion; validation.
      • Issues: Different: RT (LAD, rho-partial; Pgap attenuation); QSM (wind, leaves, finding trees); biochem (upscaling).
      • Activities: Monthly meetings? Review paper(s)? Code repository? RAMI4TLS?
      • Possible new areas: Biomechanics, radar (BIOMASS mission).
      • Discussion: All are interested in algorithms, so need to keep all in loop. Modeling and simulation essential for validation, error analysis.
    • IG4 Ecological Drivers and Applications: (Rachel Gaulton)
      • Aims: Widen uptake of TLS in ecology; increase understanding for ecological research; approaches to new ecological parameters and ecosystems; make TLS products accessible.
      • Subgroups: Two possible structures (see new developments in Friday IG4 meeting notes)
      • Ways Forward: Monthly telecons? strong communications across subgroups; TLS session at ecology mtng; brainstorming on potential new applications; review paper for ecology journal.
    • IG5 Field Measurement Protocols: (Kim Calders, Meinrad Abegg)
      • Topics: Destructive sampling, allometry; sampling designs; long-term plots; training, documentation; links to international monitoring programs.
      • Issues to look at: Reference measurements for validation; sampling, plot size, spatial variance.
      • Objectives: Guide documents (GOFC GOLD, GOFI), review paper?
      • Questionnaire outcome: TLS measurements, evaluating protocols, scanners.
      • Way forward: meetings every 2-3 months?
    • IG6 Fire Hazard Assessment and Modeling (Mark Danson)
      • Topics: Fuel properties, fuel continuity, post-fire effects.
      • Planning a review paper led by Glenn Newnham.

    Brisbane Skype Future Discussion; All-Hands RCN Telecons

    • Discussion points
      • Most important objective is to get planned papers out.
      • Separate Brisbane Skypes no longer needed if RCN includes activities reports.
      • Activities reports could be at longer intervals than one month, as at present for Brisbane Skype.
      • RCN all-hands telecons are too long if they include activities and interest group reports, especially as group is growing.
    • Conclusions
      • Authors of Brisbane papers will convene Skypes, telecons, email rounds or wiki exchanges to move papers to publication independently.
      • All-hands telecons will alternate between Activities Reports and Interest Group Reports and be scheduled every 5-6 weeks.

    Governance Issues

    • Steering Committee Membership Discussion
      • Present composition of Steering Committee is satisfactory, but could change in the future.
    • Outreach to New Participants
      • Alan observes that RCN is open to all as long as they are working directly with TLS and have something to contribute to the group.
      • Felix proposes addition of new participants in Vienna; Alan to contact them with coordinates from Felix after meeting.
      • Francophone TLS group should be included; Alan to contact Richard Fournier for liaison.
      • Interest group conveners can welcome or solicit outside participants as needed without their necessarily joining RCN.
    • Assessment
      • Proposal plan calls for ongoing assessment of success of group.
      • Measures of success: number of attendees at telecons and meetings; review papers from interest groups.
      • Assessment to be item on telecon agenda.
    • Travel and Participant Support
      • NSF Policy: Non-US participants: In-US expenses allowable; US Participants: All travel expenses allowable. Will support meeting costs at domestic and foreign venues.
      • Participant travel support to RCN meetings solicited on web site, approved by Steering Committee members, supported as funds are available.
      • Student exchanges from US to non-US participants may be supported if solicited with a short proposal and approved by the steering committee.
    • Supplementary Support from Participating Groups
      • Mark Danson with Mat Disney, Rachel Gaulton and Crystal Schaaf have proposed a Royal Society Theo Murphy International Scientific Meeting focusing on TLS for ecological and vegetation studies in November, January, or March 2016-2017 that will serve many RCN objectives.
      • Stuart Phinn has provided a list of programs available to Australians with funding for visits and exchanges to other countries that will be circulated to participants. Other steering committee members will be urged to identify similar programs and suggest participants.
    • Diversity
      • NSF has a commitment to increasing diversity in science; BU will hire a summer intern from an underrepresented minority to assist in the project. RCN participants are encouraged to reach out to underrepresented minorities to include in their work.
    • TLSIIG-RCN Relationship
      • TLSIIG to be informed of RCN activities by TLSIIG web site. TLSIIG members may join RCN by request if actively working with TLS.
    • “Brisbane 2” – Possible instrument intercomparison activity
      • Activity approved as part of original proposal; need to wait for good opportunity with ground data and validation (i.e., destructive sampling) available.
      • Harvard Forest might be possible location (see also Way Forward, Instrument Intercomparison below).
    • Automated TLS registration Benchmarking Activity – by Juha Hyyppa and colleagues at FGI. Possible follow-up by RCN participants.
    • Next RCN meeting
      • Possible participation in modeling workshop in Finland, summer 2016, Mikko Kaasalainen to host, with associated RCN activity.
      • Possible Harvard Forest ecological outreach meeting, Fall, 2016.
      • RCN participants will get together at AGU, San Francisco, December, 2015.
      • Possible meeting at ForestSat.
      • Follow up in all-hands telecons.

     

    Friday October 2

    IG4 Meeting and Discussion

    • Led by Rachel Gaulton
    • Other IG members present: Alvaro Lau, Jose Tanago, John Armston, Andy Burt (?), Angela Erb, Steve Hancock, Crystal Schaaf, Michael Schaefer, Martin van Leeuwen (Alan Strahler, Tim Condon).
    • General Discussion Points
      • IG4 members present at SilviLaser more on remote sensing side than ecology side.
      • General lack of intersection between ecologists and remote sensors at the SilivLaser meeting.
      • IG4 overlaps with other IGs, esp. IG3 Algorithms. Need to maintain close communication.
      • For outreach to ecologists, possible special sessions at ecological meetings on TLS apps; Ecol Soc Amer (ESA) meeting a possibility [Deadline for August 2016, meeting, Sept. 17, 2015, has passed, but workshop deadline is Nov. 19.] Also EGU [April, 2016; session deadline September 18, 2015.].
    • Need to be careful in outreach; 2-way interaction required. TLS not a “push button” system, remote sensors not in a position to do data prep and products for ecologists, ecologists need to learn how to use data themselves and develop their own special algorithms.
      • Possible workshops for ecologists before meetings to show what is needed?
    • Subgroup Discussion
      • Two subgroup structures proposed with somewhat different focuses.
      • Suggestion: Possible focus on topics as opposed to subgroups.
      • Possible journal review papers or overview papers on topics as goal.
      • Possible topics: TLS for ecological monitoring; applications in habitats other than forests; TLS for structural complexity and biomass; change monitoring; TLS integration with ALS / radar in ecological applications.
      • Identify topic leaders and interested participants and prepare and lead an IG meeting on the topic; detailed report to all-hands telecon.
      • Possible Google wiki / Google drive / Dropbox for virtual workspace for topic groups.
    • Conclusion
      • Topical focus more workable; will go to full IG4 for approval and further planning with telecon in first week of November.

    Ways Forward Discussions

    Way Forward for ABLS

    • Plan A: Mission-Driven Approach (as proposed in RCN)
      • Identify goals: i.e., true AGB to 10% in a 1 km2 plot of relatively homogeneous vegetation cover.
      • Determine method: e.g., acquire multiple registered scans for point clouds within a sample area, use QSM and wood density information to estimate volume and biomass to proper precision.
      • Specify software tools and candidate algorithms; develop sampling designs to meet criteria.
      • Identify specifications for the point cloud-making instrument: laser wavelength(s), divergence and sampling interval, scan volume, range, full waveform or multiple point, etc.
      • Develop preliminary instrument design to fill specifications.
      • Find funding; build prototype; get industrial partner, sell instruments.
    • Plan B: Technology-Driven Approach
      • Technology is changing very rapidly (see IG1 report on new 2D and 2D+ scanners)
      • TLS costs are dropping as capabilities are increasing.
      • Watch and evaluate new instruments and sensors for the task as they appear.
      • Analyze how each new “generation” of instruments/sensors could be applied to meet the goals and estimate suitability.
      • When technology and the market has provided an efficient and cost-effective solution, work with industrial providers to make the instrument, software, and system available.
    • IG1 members present strongly supported Plan B.
      • IG1 report (see above) already identifies new and lower cost 2D and 2D+ scanners now appearing on market.
      • Precision agriculture is driving new, lower-cost multispectral airborne and UAV laser scanners; airborne devises will migrate to terrestrial devices as we have seen at the top of the market (Riegl).
      • Autonomous autos will also require fast, low-cost scanners.
      • This is the better and faster pathway.

    Way Forward, Ecological Apps

    • Ways to engage ecologists more directly
      • TLS Sessions at Ecological Meetings
      • Michael Schaefer reports that Ecol Soc Australia will meet in Adelaide, 29 Nov – 3 Dec, 2015. Stuart Phinn will attend. Too late for program, but possible informal get-together with ecological TLS users under TLSIIG or RCN? or ad-hoc workshop?
      • Workshops at meetings to explain technology and time commitment required to use TLS.
    • Smaller, regional outreach workshops in regions possibly better than larger meeting/workshop (see Governance above).
      • Possible ecological applications outreach workshops in Europe, Australia, under RCN aegis.

    Way Forward, Instrument Intercomparison Activity

    • Need site with ground data, preferably destructive sampling of biomass.
    • Harvard Forest as possibility, good infrastructure and support for this type of activity; need to see if any destructive sampling is planned in near future.

    Way Forward, Interest Groups

    • Groups are still in evolution, need to evaluate as they progress.