Improved Estimation of Aboveground Biomass of Disturbed Grassland through Including Bare Ground and Grazing Intensity
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Area
2.2. Field Experiment and Data Collection
2.2.1. Setup of Experimental Plots
2.2.2. UAV Images and Biomass Sampling
2.3. Data Processing
2.3.1. Bare Ground Mapping and RGBVI Calculation
2.3.2. AGB Modelling
3. Results
3.1. Biomass Reference Data and Modification Assessment
3.1.1. Measured AGB and Mowing Modification Ratio (F)
3.1.2. Bare Ground Modification Metrics
3.1.3. Disturbance-Specific Models
3.2. AGB Models and Accuracy
3.3. Effects of Disturbance Severity and Bare Ground on AGB Estimation
4. Discussion
4.1. Comparison of Modifications
4.2. Implications
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Effect | Treatment | Disturbance Severity | |
---|---|---|---|
Pika | Mowing | ||
Reference | PnGn | None | None |
Pika | PmGn | Medium | None |
PhGn | High | None | |
Mowing | PnGm | None | High |
PnGh | None | Medium | |
Joint | PmGm | Medium | High |
PhGm | High | High | |
PmGh | Medium | Medium | |
PhGh | High | Medium |
Treatment | Severity | 2018 AGB (g m−2) | 2019 AGB (g m−2) | ||||||
---|---|---|---|---|---|---|---|---|---|
Min. | Mean ± SD | Max. | LSD | Min. | Mean ± SD | Max. | LSD | ||
Mowing | None | 108.00 | 200.24 ± 52.00 | 303.20 | a | 96.60 | 166.37 ± 30.68 | 219.11 | a |
Medium | 98.03 | 193.80 ± 42.26 | 273.84 | a | 51.98 | 149.90 ± 30.84 | 207.91 | b | |
High | 65.60 | 140.52 ± 34.30 | 218.96 | b | 52.96 | 120.65 ± 26.55 | 174.07 | c | |
Pika | None | 77.92 | 188.46 ± 46.59 | 284.96 | a | 52.96 | 150.21 ± 30.82 | 206.92 | a |
Medium | 71.12 | 166.47 ± 48.78 | 279.36 | a | 51.98 | 138.78 ± 38.41 | 209.43 | a | |
High | 65.60 | 179.66 ± 54.96 | 303.20 | a | 73.39 | 147.93 ± 34.23 | 219.11 | a | |
All | 65.60 | 178.20 ± 51.04 | 303.20 | 51.98 | 145.64 ± 34.97 | 219.11 |
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Shi, Y.; Gao, J.; Li, X.; Li, J.; dela Torre, D.M.G.; Brierley, G.J. Improved Estimation of Aboveground Biomass of Disturbed Grassland through Including Bare Ground and Grazing Intensity. Remote Sens. 2021, 13, 2105. https://doi.org/10.3390/rs13112105
Shi Y, Gao J, Li X, Li J, dela Torre DMG, Brierley GJ. Improved Estimation of Aboveground Biomass of Disturbed Grassland through Including Bare Ground and Grazing Intensity. Remote Sensing. 2021; 13(11):2105. https://doi.org/10.3390/rs13112105
Chicago/Turabian StyleShi, Yan, Jay Gao, Xilai Li, Jiexia Li, Daniel Marc G. dela Torre, and Gary John Brierley. 2021. "Improved Estimation of Aboveground Biomass of Disturbed Grassland through Including Bare Ground and Grazing Intensity" Remote Sensing 13, no. 11: 2105. https://doi.org/10.3390/rs13112105