Leaf-off scanning at Alice Holt

SALCA was scanning at Alice Holt, Surrey, UK, last week. The weather was showery and cold but Mark and Lucy managed to scan an Oak plot that is subject to long-term monitoring by Forest Research, and three additional plots where we will destructively sample three Oak trees in early July for woody biomass and total leaf area. We aim to test the application of SALCA for determining leaf area distributions, and the leaf-on leaf-off scans will allows us to test the use of SALCA's two wavelengths for automatic point cloud classification and separation of leaf hits from wood hits.

Full resolution SALCA scan in Oak plot at Alice Holt

Eric Casella (UK Forest Research) is coordinating the experiment and he has been busy scanning the various plots with a Leica TLS. He scanned the birch tree area below in leaf-off conditions and destructively sampled three of the trees for total woody biomass. This is really the 'gold standard' for biomass validation but the work involved is truly heroic. Cutting the trees down is just the start...

Now the hard work really starts...

SALCA returns to Delamere

SALCA has returned to Delamere Forest in Cheshire to start a year-long field campaign to monitor canopy phenology. Five plots have been located within the forest:

Plot 1: Mixed deciduous (mainly Oak and Silver birch)

Plot 2: Sweet Chestnut

Plot 3: Common Beech

Plot 4: Mixed evergreen coniferous (Corsican pine and Scots pine)

Plot 5: Japanese Larch (deciduous conifer)

Leaf-off measurements are nearly complete - just in time as green buds have already started appearing in the Silver birch. Spring is a busy time in the canopy so Mark and Lucy plan to scan frequently throughout this period to capture the 3D characteristics of development and activity within the canopy. The data collected at Delamere will form a significant part of Lucy's PhD.

SALCA at Plot 1

Following a review of the data we collected in Australia, and preparation for our upcoming field campaigns, we have recently implemented a couple of improvements to the instrument and scanning procedures. This has included introducing new filter combinatons to balance the power of the lasers and swapping the petrol generator (which gave up on our first day at Delamere!) with a 24v battery - this has the added benefits of being quiet and much easier to carry!

Mark at Plot 3

New TLS research at Forest Research

In mid January the SALCA team participated in discussions at Forest Research UK to plan a new TLS experiment to scan leaf-off and leaf-on woodland at Alice Holt, Surrey. The plan is to scan the plots in March and July and then to carry out destructive sampling to measure the wood biomass and total leaf area of a number of Oak trees. We were hosted by Eric Casella and James Morison (Forest Research) and others from University College London, University of Grenoble, France, and Tampere University of Technology (TUT), Finland

L to R. Andy Burt (UCL), Lucy Walker (USalford), Markku Akerblom (TUT), Rachel Gaulton (UNewcastle), Eric Casella (ForestResearch), Mark Danson (USalford), Pasi Raumonen (TUT), Mikko Kaasalainen (TUT), Mat Disney UCL), James Morison (Forest Research), Frank Hetroy (UGrenoble)

Royal Society Leverhulme Fellowship for Mark Danson

Late breaking news is that Mark Danson has been awarded a Royal Society Leverhulme Senior Research Fellowship to work on SALCA data processing and analysis. The award provides funding to replace Mark's teaching for a period of 12 months and will enable him to work full time on research. The work in Australia set the scene for the project and he will continue to work on SALCA related projects through to October 2014.

Press coverage of the news can be found at the following links:

http://royalsociety.org/news/2013/Leverhulme-Trust-Fellowships-announced/

http://www.salford.ac.uk/news/laser-device-to-give-most-detailed-ever-picture-of-climate-change-effects-on-forests

https://bgreenblue.wordpress.com/tag/biomass/

http://www.surveyequipment.com/news/article/salford-researcher-creates-new-forest-canopy-surveying-technology-191805.html

http://www.electrooptics.com/news/news_story.php?news_id=1859

http://sensorsandsystems.com/news/top-stories/corporate-news/31257-researcher-creates-unique-lasser-for-forest-vegetation-surveys.html

http://www.timeshighereducation.co.uk/news/campus-round-up-22-august-2013/2006578.article

More action from Australia

Tuesday saw us back at Karawatha Forest park to collect SALCA data along side the Riegl VZ400 and Faro instrument. In addition to the laser scanner data the the team are collecting field spectrometer data to characterise the spectral properties of leaves and bark. Sampling the upper canopy requires the use of an oversize slingshot which propels bean bag and string into the canopy; the bean bag wraps around branches and these are then pulled down for sampling - sometimes it works, and sometimes it goes wrong!

Steve Hancock and Andrew Burt (University College London) attempt to untangle the sling-shot string!

Rachel and Mat Disney (University College London) use an ASD Fieldspec to measure leaf reflectance and transmittance

 Short clip of SALCA in action - the noise of the generator wins over the birdsong for most of the clip

SALCA goes to Australia

The SALCA team is in Brisbane, Australia, taking part in an international terrestrial laser scanner inter-comparison study. The experiment has been organized as part of the TLS International Interest Group (TLSIIG) formed at Silvilaser in Vancouver last September. We are joined teams from the US and Australia to compare the data from a range of different TLS instruments for measuring forest canopy structure at two sites close to Brisbane.

The University of Boston and University of Massachusetts have brought the Dual Wavelength Echidna Lidar (DWEL) and the short range but handy Canopy Biomass Lidar (CBL), the Queensland Government Department for Science, Innovation, Technology, Innovation and the Arts (DSITIA) and TERN (University of Queensland) a Riegl 400VZ, and the University of Southern Queensland a Faro Focus 3D.

First obstacle overcome: SALCA makes it in one piece to Australia much to the relief of Mark, Steve, Rachel and Lucy

After spending a day carrying out calibration measurements in the lab we collected the first field data today at Karawatha Forest Park just south of Brisbane. The plots we are using are part of the Australian Terrestrial Ecosystem Research Network (TERN) and the field experiments are coordinated by John Armston (DSITIA) and Glen Newnham (CSIRO). They have done a great job and we had over 30 scientists in the field today.

Another first for the SALCA team: Lucy looks pleased after collecting the first dual wavelength TLS data in the southern hemisphere!

Glen Newnham (CSIRO) takes a close look at SALCA

More on the TLSIIG experiments from TERN here

SALCA down on the farm

June saw SALCA return to Newcastle for NERC-funded field experiments testing the sensitivity of the instrument to changes in canopy moisture content. The (literal) field experiment, involving 22 potted trees at the University’s Cockle Park Farm, involves repeated SALCA scans as drought stress is induced in groups of trees over a period of 1 month, alongside scans of regularly watered controls. The SALCA signal will be compared to a range of physiological measurements and to spectral data acquired with an ASD field spectrometer. The experiment is now well under way, and after initial teething problems with windthrow and over inquisitive and hungry livestock, the drying groups of small-leaved lime (Tilia cordata) and Austrian pine have been gradually wilting for a little over a week. Steve has got to grips with the operation of a cherry picker and fingers are crossed that the so far almost ideal weather will last! Early results from the experiments will be presented in a poster at INTECOL, London in August. 

 

Setting up the experiments

 

 

What happens when sheep get hold of a windblown experimental tree, and a possible culprit.

Clockwise: SALCA in the field, a small-leaved lime drying group with intensity calibration board, measuring stomatal conductance and contact probe measurments of leaf reflectance properties.