Measuring Vegetation Phenology with Near-Surface Remote Sensing in a Temperate Deciduous Forest: Effects of Sensor Type and Deployment
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Area
2.2. Field Measurements
2.2.1. Digital Camera Measurements
2.2.2. Spectroradiometer Measurements
2.2.3. Radiometer Measurements
2.3. Data Analysis
2.3.1. Vegetation Index from Digital Camera
2.3.2. Vegetation Index from Spectroradiometer
2.3.3. Vegetation Index from Radiometer
2.3.4. Phenophase Extraction
2.3.5. Statistical Analysis
3. Results and Discussion
3.1. Inclination-Angle Effect on the Vegetation Indices and Phenophases
3.2. Azimuth-Angle Effect on the Vegetation Indices and Phenophases
3.3. Sensor-Type Effect on the Vegetation Indices and Phenophases
4. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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VI | Inclination Angle | 2015 | 2016 | 2018 | |||
---|---|---|---|---|---|---|---|
Spring | Autumn | Spring | Autumn | Spring | Autumn | ||
GCCC | 30° | 0.987 | 0.993 | 0.991 | 1.000 | 1.000 | 1.000 |
45° | 0.982 | 0.984 | 1.000 | 1.000 | 0.991 | 1.000 | |
60° | 0.982 | 0.989 | 1.000 | 1.000 | 0.891 | 1.000 | |
NDVIN | 30° | 0.984 | 0.951 | 1.000 | 1.000 | 1.000 | 1.000 |
45° | 0.982 | 0.945 | 0.817 | 1.000 | 1.000 | 1.000 | |
60° | 0.973 | 0.951 | 0.830 | 0.964 | 1.000 | 0.983 | |
NDVIB | 81° | 0.980 | 0.992 |
VI | Year | Inclination Angle | SOS | MOS | POS | SOF | MOF | EOF | LOS1 | LOS2 |
---|---|---|---|---|---|---|---|---|---|---|
GCCC | 2015 | 30° | 0 ± 5 | −1 ± 2 | −1 ± 5 | 4 ± 7 | 2 ± 3 | 1 ± 7 | 3 ± 3 | 1 ± 9 |
45° | −5 ± 7 | −2 ± 2 | 0 ± 7 | 0 ± 8 | 1 ± 3 | 2 ± 8 | 3 ± 4 | 7 ± 10 | ||
60° | −12 ± 8 * | −6 ± 4 * | −1 ± 8 | −11 ± 12 | −2 ± 5 | 6 ± 12 | 4 ± 6 | 18 ± 15 | ||
2016 | 30° | −2 ± 8 | −2 ± 3 | −3 ± 8 | −1 ± 4 | 1 ± 2 | 3 ± 4 | 3 ± 4 | 5 ± 9 | |
45° | −3 ± 8 | −3 ± 3 | −4 ± 8 | 0 ± 4 | 1 ± 2 | 1 ± 4 | 4 ± 4 | 4 ± 9 | ||
60° | −3 ± 8 | −5 ± 3 | −6 ± 8 | −3 ± 5 | 1 ± 2 | 5 ± 5 | 6 ± 4 | 8 ± 10 | ||
2018 | 30° | 0 ± 5 | −1 ± 2 | −3 ± 5 | 0 ± 8 | 0 ± 3 | 0 ± 8 | 2 ± 4 | 1 ± 10 | |
45° | 0 ± 4 | −2 ± 2 | −4 ± 4 | 0 ± 8 | 0 ± 3 | 0 ± 8 | 2 ± 4 | 0 ± 9 | ||
60° | 1 ± 4 | −3 ± 2 * | −7 ± 4 * | −2 ± 9 | 0 ± 4 | 2 ± 9 | 3 ± 4 | 1 ± 10 | ||
NDVIN | 2015 | 30° | 3 ± 12 | −1 ± 4 | −6 ± 12 | −8 ± 9 | −1 ± 4 | 7 ± 9 | 0 ± 6 | 3 ± 15 |
45° | 4 ± 11 | −2 ± 4 | −8 ± 11 | −8 ± 10 | −1 ± 4 | 7 ± 10 | 1 ± 6 | 3 ± 15 | ||
60° | 6 ± 10 | −4 ± 4 | −14 ± 10 * | 2 ± 7 | 1 ± 3 | 0 ± 7 | 5 ± 5 | −6 ± 12 | ||
2016 | 30° | 7 ± 12 | 0 ± 5 | −7 ± 12 | −4 ± 11 | −1 ± 5 | 3 ± 11 | −1 ± 7 | −5 ± 16 | |
45° | 10 ± 12 | −1 ± 5 | −12 ± 12 | −6 ± 11 | −1 ± 5 | 4 ± 11 | −1 ± 7 | −6 ± 16 | ||
60° | 12 ± 12 | −1 ± 5 | −14 ± 12 | −3 ± 11 | −2 ± 5 | 0 ± 11 | −1 ± 7 | −12 ± 16 | ||
2018 | 30° | −3 ± 7 | −1 ± 3 | 2 ± 7 | −2 ± 6 | −1 ± 3 | −1 ± 6 | −1 ± 4 | 2 ± 10 | |
45° | −2 ± 6 | −1 ± 3 | 1 ± 6 | −4 ± 8 | −2 ± 3 | −1 ± 8 | −1 ± 5 | 2 ± 10 | ||
60° | −3 ± 6 | −3 ± 3 | −3 ± 6 | 0 ± 8 | −1 ± 3 | −2 ± 8 | 1 ± 4 | 1 ± 10 | ||
NDVIB | 2016 | 81° | 0 ± 4 | 0 ± 2 | 1 ± 4 | 1 ± 11 | −2 ± 5 | −5 ± 11 | −2 ± 6 | −5 ± 12 |
Year | Inclination Angle | SOS | MOS | POS | SOF | MOF | EOF | LOS1 | LOS2 |
---|---|---|---|---|---|---|---|---|---|
2015 | 30° | −1 ± 7 | 2 ± 2 | 2 ± 7 | 0 ± 11 | 0 ± 5 | 0 ± 11 | −2 ± 5 | −1 ± 13 |
45° | −3 ± 11 | 3 ± 3 | 8 ± 11 | −3 ± 12 | −1 ± 4 | 1 ± 12 | −4 ± 6 | 3 ± 16 | |
60° | −10 ± 10 | −1 ± 3 | 8 ± 10 | −2 ± 17 | −1 ± 6 | 1 ± 17 | 0 ± 7 | 10 ± 19 | |
2016 | 30° | 2 ± 13 | −1 ± 6 | −4 ± 13 | 0 ± 8 | 0 ± 3 | 0 ± 8 | 1 ± 7 | −1 ± 15 |
45° | −1 ± 11 | −2 ± 5 | −4 ± 11 | 0 ± 8 | 1 ± 3 | 2 ± 8 | 3 ± 6 | 2 ± 13 | |
60° | −1 ± 11 | −3 ± 5 | −4 ± 11 | 0 ± 9 | 1 ± 4 | 3 ± 9 | 4 ± 6 | 4 ± 14 | |
2018 | 30° | 0 ± 8 | 0 ± 3 | 0 ± 8 | −1 ± 9 | 0 ± 3 | 0 ± 9 | 0 ± 5 | 1 ± 12 |
45° | 1 ± 7 | −1 ± 3 | −3 ± 7 | 0 ± 8 | 0 ± 3 | 1 ± 8 | 2 ± 4 | 0 ± 11 | |
60° | 0 ± 7 | −2 ± 3 | −5 ± 7 | 0 ± 11 | 1 ± 4 | 2 ± 11 | 3 ± 5 | 2 ± 13 |
VI | Azimuth Angle | 2015 | 2016 | 2018 | |||
---|---|---|---|---|---|---|---|
Spring | Autumn | Spring | Autumn | Spring | Autumn | ||
GCCC | E | 0.970 | 0.993 | 0.991 | 1.000 | 0.745 | 1.000 |
S | 0.994 | 0.974 | 1.000 | 0.986 | 0.945 | 0.967 | |
W | 0.997 | 1.000 | 0.991 | 1.000 | 0.955 | 0.983 | |
NDVIN | E | 0.951 | 0.991 | 0.976 | 1.000 | 0.855 | 1.000 |
S | 0.956 | 0.965 | 0.988 | 0.976 | 0.855 | 1.000 | |
W | 0.979 | 0.996 | 0.952 | 1.000 | 0.900 | 0.983 |
VI | Year | Azimuth Angle | SOS | MOS | POS | SOF | MOF | EOF | LOS1 | LOS2 |
---|---|---|---|---|---|---|---|---|---|---|
GCCC | 2015 | E | −12 ± 6 * | −8 ± 3 * | −4 ± 6 | 1 ± 12 | 2 ± 5 | 4 ± 12 | 11 ± 5 * | 16 ± 13 |
S | −17 ± 7 * | −7 ± 3 * | 3 ± 7 | 2 ± 10 | 1 ± 4 | 1 ± 10 | 9 ± 5 | 18 ± 13 | ||
W | −6 ± 7 | −2 ± 2 | 3 ± 7 | −7 ± 13 | −1 ± 5 | 5 ± 13 | 1 ± 5 | 11 ± 14 | ||
2016 | E | 0 ± 6 | −4 ± 3 * | −9 ± 6 | −4 ± 9 | 2 ± 3 | 8 ± 9 | 6 ± 4 | 7 ± 11 | |
S | 0 ± 7 | −2 ± 3 | −5 ± 7 | −7 ± 13 | −2 ± 5 | 2 ± 13 | 0 ± 6 | 2 ± 15 | ||
W | 2 ± 6 | −1 ± 2 | −4 ± 6 | −1 ± 8 | 1 ± 3 | 3 ± 8 | 2 ± 4 | 1 ± 10 | ||
2018 | E | 2 ± 5 | −1 ± 2 | −4 ± 5 | 1 ± 10 | 1 ± 4 | 1 ± 10 | 2 ± 4 | −1 ± 11 | |
S | 1 ± 5 | −2 ± 2 | −4 ± 5 | 2 ± 8 | 0 ± 3 | −2 ± 8 | 1 ± 4 | −3 ± 9 | ||
W | 1 ± 5 | 0 ± 2 | −1 ± 5 | −3 ± 10 | −1 ± 4 | 2 ± 10 | −1 ± 4 | 1 ± 11 | ||
NDVIN | 2015 | E | −3 ± 8 | −5 ± 3 * | −7 ± 8 | −3 ± 11 | 0 ± 5 | 2 ± 11 | 4 ± 6 | 5 ± 14 |
S | −10 ± 10 | −9 ± 4 * | −7 ± 10 | 1 ± 13 | 0 ± 6 | −2 ± 13 | 8 ± 7 | 8 ± 16 | ||
W | −10 ± 9 | −6 ± 3 * | −1 ± 9 | 0 ± 10 | 1 ± 4 | 1 ± 10 | 6 ± 5 | 11 ± 14 | ||
2016 | E | −2 ± 7 | −2 ± 3 | −2 ± 7 | −11 ± 10 | −4 ± 4 | 2 ± 10 | −2 ± 5 | 5 ± 12 | |
S | −6 ± 7 | −3 ± 3 | 0 ± 7 | −4 ± 12 | −2 ± 5 | −1 ± 12 | 1 ± 6 | 6 ± 14 | ||
W | −6 ± 6 | −4 ± 3 | −1 ± 6 | −1 ± 12 | 0 ± 5 | 2 ± 12 | 4 ± 6 | 8 ± 13 | ||
2018 | E | 8 ± 6 | −1 ± 3 | −10 ± 6 | 5 ± 7 | 2 ± 3 | 0 ± 7 | 3 ± 4 | −8 ± 9 | |
S | 6 ± 6 | −2 ± 3 | −10 ± 6 | 7 ± 6 | 2 ± 3 | −3 ± 6 | 4 ± 4 | −9 ± 8 | ||
W | 7 ± 6 | −2 ± 3 | −10 ± 6 | 4 ± 9 | 1 ± 4 | −2 ± 9 | 2 ± 5 | −9 ± 11 |
VI | Year | SOS | MOS | POS | SOF | MOF | EOF | LOS1 | LOS2 |
---|---|---|---|---|---|---|---|---|---|
GCCC vs. NDVIN | 2015 | 1 ± 7 | 4 ± 3 * | 8 ± 7 | −4 ± 14 | −1 ± 6 | 3 ± 14 | −5 ± 7 | 1 ± 16 |
2016 | 2 ± 6 | 3 ± 3 * | 5 ± 6 | −5 ± 9 | 0 ± 4 | 4 ± 9 | −4 ± 5 | 2 ± 11 | |
2018 | 4 ± 3 * | 2 ± 1 | −1 ± 3 | 4 ± 8 | 3 ± 3 | 3 ± 8 | 2 ± 3 | −2 ± 8 | |
GCCC vs. NDVIB | 2015 | 14 ± 9 * | 7 ± 3 * | −1 ± 9 | 7 ± 11 | 3 ± 5 | 0 ± 11 | −4 ± 6 | −15 ± 15 |
2016 | 4 ± 5 | 4 ± 1 * | 4 ± 5 | −9 ± 11 | 0 ± 5 | 9 ± 11 | −4 ± 6 | 5 ± 12 | |
2018 | 4 ± 3 | 0 ± 1 | −4 ± 3 | 18 ± 8 * | 8 ± 4 * | −3 ± 8 | 7 ± 4 * | −7 ± 9 | |
NDVIN vs. NDVIB | 2015 | 13 ± 10 | 2 ± 4 | −8 ± 10 | 10 ± 11 | 4 ± 5 | −3 ± 11 | 1 ± 6 | −16 ± 14 |
2016 | 2 ± 6 | 1 ± 3 | −1 ± 6 | −4 ± 11 | 0 ± 6 | 5 ± 11 | 0 ± 6 | 3 ± 13 | |
2018 | 0 ± 2 | −2 ± 1 * | −3± 2 | 14 ± 8 * | 4 ± 3 | −6 ± 8 | 6 ± 4 | −5 ± 8 |
VI | Year | SOS | MOS | POS | SOF | MOF | EOF | LOS1 | LOS2 |
---|---|---|---|---|---|---|---|---|---|
GCCN vs. GCCC | 2015 | 1 ± 7 | −2 ± 3 | −5 ± 7 | 5 ± 15 | 2 ± 6 | −1 ± 15 | 4 ± 6 | −2 ± 16 |
2016 | 1 ± 5 | −3 ± 2 | −6 ± 5 | −3 ± 11 | −1 ± 4 | 2 ± 11 | 2 ± 5 | 1 ± 12 | |
2018 | −2 ± 3 | 0 ± 2 | 1 ± 3 | 1 ± 8 | 0 ± 3 | −1 ± 8 | 0 ± 4 | 1 ± 9 | |
NDVIBS vs. NDVIB | 2015 | 23 ± 11 * | 13 ± 4 * | 3 ± 11 | 1 ± 14 | −1 ± 6 | 4 ± 14 | −15 ± 7 * | −27 ± 18 |
2016 | 12 ± 5 * | 5 ± 2 * | −2 ± 5 | −15 ± 17 | −5 ± 7 | −4 ± 17 | −10 ± 7 * | −8 ± 18 | |
2018 | 5 ± 5 | 1 ± 2 | −3 ± 5 | 8 ± 10 | 2 ± 5 | 5 ± 10 | 1 ± 5 | −10 ± 11 |
© 2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
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Liu, F.; Wang, X.; Wang, C. Measuring Vegetation Phenology with Near-Surface Remote Sensing in a Temperate Deciduous Forest: Effects of Sensor Type and Deployment. Remote Sens. 2019, 11, 1063. https://doi.org/10.3390/rs11091063
Liu F, Wang X, Wang C. Measuring Vegetation Phenology with Near-Surface Remote Sensing in a Temperate Deciduous Forest: Effects of Sensor Type and Deployment. Remote Sensing. 2019; 11(9):1063. https://doi.org/10.3390/rs11091063
Chicago/Turabian StyleLiu, Fan, Xingchang Wang, and Chuankuan Wang. 2019. "Measuring Vegetation Phenology with Near-Surface Remote Sensing in a Temperate Deciduous Forest: Effects of Sensor Type and Deployment" Remote Sensing 11, no. 9: 1063. https://doi.org/10.3390/rs11091063