Determining Subarctic Peatland Vegetation Using an Unmanned Aerial System (UAS)
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Site
2.2. Vegetation Field Plots
2.3. UAS Image Data Collection
2.4. Georectification
2.5. Texture Analysis
2.6. Data Extraction and Statistical Analysis
3. Results
Error Analysis and Cover Class Assessment
4. Discussion
Image Classification and Error Estimates
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Cover Type | Soils and Vegetation | Dominant Vegetative Species | % | Second Dominant Vegetative Species | % | Diversity Index | Connecting Letter Report |
---|---|---|---|---|---|---|---|
Tall Shrub | Ombrotrophic, found in dry areas | Dwarf Birch (Betula nana) | 18.7 | Cloudberry (Rubus chamaemorus) | 11.4 | 1.53 | A |
Hummock | Ombrotrophic, on permafrost | Crowberry (Empetrum hermaphroditum) | 16.9 | Hares Tail (Eriophorum vaginatum) | 16.1 | 1.44 | A |
Semi-Wet | Ombrotrophic or minerotrophic | Spagnum sp. | 43.1 | Hares Tail (Eriophorum vaginatum) | 15.6 | 0.61 | B |
Wet | Ombrotrophic | Open Water | 43.1 | Spagnum | 8.2 | 0.70 | B |
Tall Graminoid | Wet minerotrophic | Carex sp. | 30.7 | Cotton Tail (Eriophorum angustafolium) | 11.5 | 0.90 | B |
Cover Type | Abbrev. | Pixels | Percent |
---|---|---|---|
Other | OT | 1,028,465 | 0.7% |
Rock | RK | 4,882,573 | 3.1% |
Tall Graminoid | TG | 38,379,784 | 24.4% |
Hummock | HM | 42,193,103 | 26.8% |
Tall Shrub | TS | 26,852,493 | 17.1% |
Water | H2O | 787,946 | 0.5% |
Wet | WT | 8,538,871 | 5.4% |
Semi-Wet | SW | 34,574,233. | 22.0% |
Total | TT | 157,237,468 | 100.0% |
Training Prediction Rate | ||||||||
---|---|---|---|---|---|---|---|---|
Classes | H2O | HM | OT | RK | SW | TG | TS | WT |
H2O | 1.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
HM | 0.00 | 0.82 | 0.00 | 0.00 | 0.07 | 0.08 | 0.02 | 0.00 |
OT | 0.00 | 0.00 | 0.96 | 0.04 | 0.00 | 0.00 | 0.00 | 0.00 |
RK | 0.00 | 0.01 | 0.02 | 0.79 | 0.01 | 0.03 | 0.13 | 0.02 |
SW | 0.00 | 0.13 | 0.00 | 0.01 | 0.77 | 0.08 | 0.00 | 0.02 |
TG | 0.00 | 0.13 | 0.00 | 0.01 | 0.11 | 0.50 | 0.25 | 0.00 |
TS | 0.00 | 0.04 | 0.00 | 0.02 | 0.03 | 0.32 | 0.59 | 0.00 |
WT | 0.00 | 0.19 | 0.00 | 0.00 | 0.13 | 0.12 | 0.01 | 0.55 |
Validation Prediction Rate | ||||||||
---|---|---|---|---|---|---|---|---|
Classes | H2O | HM | OT | RK | SW | TG | TS | WT |
H2O | 1.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
HM | 0.00 | 0.84 | 0.00 | 0.00 | 0.07 | 0.08 | 0.02 | 0.01 |
OT | 0.00 | 0.00 | 0.95 | 0.05 | 0.00 | 0.00 | 0.00 | 0.00 |
RK | 0.00 | 0.01 | 0.02 | 0.79 | 0.01 | 0.03 | 0.13 | 0.02 |
SW | 0.00 | 0.14 | 0.00 | 0.00 | 0.75 | 0.08 | 0.00 | 0.02 |
TG | 0.00 | 0.14 | 0.00 | 0.00 | 0.11 | 0.50 | 0.25 | 0.00 |
TS | 0.00 | 0.04 | 0.00 | 0.02 | 0.03 | 0.33 | 0.58 | 0.00 |
WT | 0.00 | 0.20 | 0.00 | 0.00 | 0.13 | 0.11 | 0.01 | 0.55 |
Classes | Training | Error | Validation | Error |
---|---|---|---|---|
Omission | Comission | Omission | Comission | |
H2O | 0.00 | 0.00 | 0.00 | 0.00 |
HM | 0.29 | 0.18 | 0.30 | 0.16 |
OT | 0.03 | 0.04 | 0.02 | 0.05 |
RK | 0.20 | 0.21 | 0.17 | 0.21 |
SW | 0.29 | 0.23 | 0.29 | 0.25 |
TG | 0.52 | 0.50 | 0.52 | 0.50 |
TS | 0.32 | 0.41 | 0.32 | 0.42 |
WT | 0.13 | 0.45 | 0.15 | 0.46 |
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Palace, M.; Herrick, C.; DelGreco, J.; Finnell, D.; Garnello, A.J.; McCalley, C.; McArthur, K.; Sullivan, F.; Varner, R.K. Determining Subarctic Peatland Vegetation Using an Unmanned Aerial System (UAS). Remote Sens. 2018, 10, 1498. https://doi.org/10.3390/rs10091498
Palace M, Herrick C, DelGreco J, Finnell D, Garnello AJ, McCalley C, McArthur K, Sullivan F, Varner RK. Determining Subarctic Peatland Vegetation Using an Unmanned Aerial System (UAS). Remote Sensing. 2018; 10(9):1498. https://doi.org/10.3390/rs10091498
Chicago/Turabian StylePalace, Michael, Christina Herrick, Jessica DelGreco, Daniel Finnell, Anthony John Garnello, Carmody McCalley, Kellen McArthur, Franklin Sullivan, and Ruth K. Varner. 2018. "Determining Subarctic Peatland Vegetation Using an Unmanned Aerial System (UAS)" Remote Sensing 10, no. 9: 1498. https://doi.org/10.3390/rs10091498