case studies in the use of to study ecological questions ... · present preliminary ecological case...

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Case studies in the use of UAVs to study ecological questions in the in situ oil sands region of Alberta Tobias W.H. Tan 1 & Scott E. Nielsen 1 1 Department of Renewable Resources, University of Alberta Introduction The in situ oil sands region in Northern Alberta contains a substantial energy exploration footprint now undergoing recovery and restoration as part of environmental stewardship efforts. Managers need ecological information about how different forest types, disturbance histories and treatments are regenerating and how to cost effectively monitor recovery in order to satisfy reclamation objectives. Historically, this information was obtained using timeintensive field surveys dependent on human measures of structure and height. More recently, lowcost unmanned aerial vehicle (UAV) platforms, coupled with developing workflows for deriving 3D vegetation data, have been yielding new ways for obtaining ecological information relevant to footprint recovery. We present preliminary ecological case studies using UAVonly data collection from field trials in Northern Alberta to demonstrate how this technology can be used to better understand forest regeneration and processes affecting regeneration patterns by natural and manmade disturbances. Methods UAV surveys using 3DR Iris+, 16mp Ricoh GR camera and Hemisphere S320 RTK for ground control conducted in the Fort McMurray area in Summer 2016. Discussion We found sufficient precision and signal using UAVs and photogrammetry to observe ecologically meaningful trends and patterns in seismic line recovery. More development on standardized and optimized protocols is ongoing and as methods continue to improve and larger areas are surveyed, UAVderived products and findings are expected to improve in accuracy, applicability and their ability to be generalized. We anticipate that UAVphotogrammetry based techniques will become an increasingly useful tool for answering ecological questions, collecting actionable information, and the adaptive management of our environmental footprints in the in situ oil sands region of Alberta. Forest structure point clouds processed using preliminary photogrammetry workflows in Agisoft Photoscan to produce 2 cm pixel forest and terrain models. Acknowledgements We thank Transport Canada and Nav Canada for clearance and assistance conducting UAV Ops in the North Oil Sands ATF area, Brian Hinrichsen for tireless field assistance, and the sponsors of BERA and the ABC Chairs program for supporting this study. 3DR, ESRI, Agisoft, and Benchmark.ca also supported this project with academic discounts for equipment and software. Case 1: Regen by type of line (width) Case 2: Regen post fire Landscape visualization, vegetationonly model construction, and virtual point/zonal transects conducted in ArcGIS; data validated, analyzed and used in ecological modelling. Case 3: Regen by road distance Regeneration was greater in seismic lines burned by the Richardson fire (2011), controlling for line width, age and stand type (F 1,896 = 104.3, p < 0.001, n = 10). At this point, regeneration on burned seismic lines is limited to the shrub and sapling stage so the magnitude of the effect was small (mean difference in cover height = 0.15 m ± 0.01 m), but this is expected to increase over time. At a local scale (<150m), distance from road was found to have no significant effect on seismic line regeneration (F 175,1135 = 1.00, p = 0.494, n = 8). This may change when compared to further distances and at a regional scales where human access and activity differ. 0 0.5 1 1.5 2 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 Mean Regen Height (m) Distance from Road (m) Height of regeneration cover in recently disturbed (10 years since disturbance) seismic lines was found to be greater in 3D seismic lines than 2D seismic lines from the same period (mean difference in cover = 0.13 m ± 0.01 m; F 1,1307 = 23.87, p < 0.001, n =8), while we found no relationship between height of regeneration cover and height of the adjacent forest stand (F 1,1307 = 0.41, p = 0.521, n = 8). 2D seismic lines 3D seismic lines Burnt (2011) Unburnt

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Page 1: Case studies in the use of to study ecological questions ... · present preliminary ecological case studies using UAV‐only data collection from field trials in Northern Alberta

Case studies in the use of UAVs to study ecological questionsin the in situ oil sands region of Alberta

Tobias W.H. Tan1 & Scott E. Nielsen1

1 Department of Renewable Resources, University of Alberta

IntroductionThe in situ oil sands region in Northern Alberta contains a substantial energy exploration footprint now undergoingrecovery and restoration as part of environmental stewardship efforts. Managers need ecological information abouthow different forest types, disturbance histories and treatments are regenerating and how to cost effectively monitorrecovery in order to satisfy reclamation objectives. Historically, this information was obtained using time‐intensive fieldsurveys dependent on human measures of structure and height.

More recently, low‐cost unmanned aerial vehicle (UAV) platforms, coupled with developing workflows for deriving 3Dvegetation data, have been yielding new ways for obtaining ecological information relevant to footprint recovery. Wepresent preliminary ecological case studies using UAV‐only data collection from field trials in Northern Alberta todemonstrate how this technology can be used to better understand forest regeneration and processes affectingregeneration patterns by natural and man‐made disturbances.

Methods

UAV surveys using 3DR Iris+, 16mp RicohGR camera and Hemisphere S320 RTK forground control conducted in the FortMcMurray area in Summer 2016.

DiscussionWe found sufficient precision and signal using UAVs and photogrammetry to observe ecologically meaningful trendsand patterns in seismic line recovery. More development on standardized and optimized protocols is ongoing and asmethods continue to improve and larger areas are surveyed, UAV‐derived products and findings are expected toimprove in accuracy, applicability and their ability to be generalized. We anticipate that UAV‐photogrammetry basedtechniques will become an increasingly useful tool for answering ecological questions, collecting actionableinformation, and the adaptive management of our environmental footprints in the in situ oil sands region of Alberta.

Forest structure point clouds processed usingpreliminary photogrammetry workflows inAgisoft Photoscan to produce 2 cm pixel forestand terrain models.

AcknowledgementsWe thank Transport Canada and Nav Canadafor clearance and assistance conducting UAVOps in the North Oil Sands ATF area, BrianHinrichsen for tireless field assistance, andthe sponsors of BERA and the ABC Chairsprogram for supporting this study. 3DR, ESRI,Agisoft, and Bench‐mark.ca also supportedthis project with academic discounts forequipment and software.

Case 1: Regen by type of line (width) Case 2: Regen post fire

Landscape visualization, vegetation‐only modelconstruction, and virtual point/zonal transectsconducted in ArcGIS; data validated, analyzedand used in ecological modelling.

Case 3: Regen by road distance

Regeneration was greater in seismic lines burnedby the Richardson fire (2011), controlling for linewidth, age and stand type (F1,896 = 104.3, p < 0.001,n = 10). At this point, regeneration on burnedseismic lines is limited to the shrub and saplingstage so the magnitude of the effect was small(mean difference in cover height = 0.15 m ± 0.01m), but this is expected to increase over time.

At a local scale (<150m), distance from road wasfound to have no significant effect on seismic lineregeneration (F175,1135 = 1.00, p = 0.494, n = 8). Thismay change when compared to further distancesand at a regional scales where human access andactivity differ.

0

0.5

1

1.5

2

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150

Mean

 Regen

 Height (m

)

Distance from Road (m)

Height of regeneration cover in recently disturbed(10 years since disturbance) seismic lines was foundto be greater in 3D seismic lines than 2D seismiclines from the same period (mean difference incover = 0.13 m ± 0.01 m; F1,1307 = 23.87, p < 0.001, n= 8), while we found no relationship between heightof regeneration cover and height of the adjacentforest stand (F1,1307 = 0.41, p = 0.521, n = 8).

2D seismic lines

3D seismic lines

Burnt (2011)

Unburnt