Deriving seasonal dynamics in ecosystem properties of semi-arid savanna grasslands from in situ-based hyperspectral reflectance

Research output: Contribution to journal › Journal article › Research › peer-review

Standard

Deriving seasonal dynamics in ecosystem properties of semi-arid savanna grasslands from in situ-based hyperspectral reflectance. / Tagesson, Håkan Torbern; Fensholt, Rasmus; Huber, S. ; Horion, Stéphanie Marie Anne F; Guiro, Idrissa; Ehammer, Andrea; Ardö, J.

In: Biogeosciences, Vol. 12, No. 15, 2015, p. 4621-4635.

Research output: Contribution to journal › Journal article › Research › peer-review

Harvard

Tagesson, HT, Fensholt, R, Huber, S, Horion, SMAF, Guiro, I, Ehammer, A & Ardö, J 2015, 'Deriving seasonal dynamics in ecosystem properties of semi-arid savanna grasslands from in situ-based hyperspectral reflectance', Biogeosciences, vol. 12, no. 15, pp. 4621-4635. https://doi.org/10.5194/bg-12-4621-2015

APA

Tagesson, H. T., Fensholt, R., Huber, S., Horion, S. M. A. F., Guiro, I., Ehammer, A., & Ardö, J. (2015). Deriving seasonal dynamics in ecosystem properties of semi-arid savanna grasslands from in situ-based hyperspectral reflectance. Biogeosciences, 12(15), 4621-4635. https://doi.org/10.5194/bg-12-4621-2015

Vancouver

Tagesson HT, Fensholt R, Huber S, Horion SMAF, Guiro I, Ehammer A et al. Deriving seasonal dynamics in ecosystem properties of semi-arid savanna grasslands from in situ-based hyperspectral reflectance. Biogeosciences. 2015;12(15):4621-4635. https://doi.org/10.5194/bg-12-4621-2015

Author

Tagesson, Håkan Torbern ; Fensholt, Rasmus ; Huber, S. ; Horion, Stéphanie Marie Anne F ; Guiro, Idrissa ; Ehammer, Andrea ; Ardö, J. / Deriving seasonal dynamics in ecosystem properties of semi-arid savanna grasslands from in situ-based hyperspectral reflectance. In: Biogeosciences. 2015 ; Vol. 12, No. 15. pp. 4621-4635.

Bibtex

@article{1f1ad217a6ce479688805ceb37df970f,
title = "Deriving seasonal dynamics in ecosystem properties of semi-arid savanna grasslands from in situ-based hyperspectral reflectance",
abstract = "This paper investigates how hyperspectral reflectance (between 350 and 1800 nm) can be used to infer ecosystem properties for a semi-arid savanna grassland in West Africa using a unique in situ-based multi-angular data set of hemispherical conical reflectance factor (HCRF) measurements. Relationships between seasonal dynamics in hyperspectral HCRF and ecosystem properties (biomass, gross primary productivity (GPP), light use efficiency (LUE), and fraction of photosynthetically active radiation absorbed by vegetation (FAPAR)) were analysed. HCRF data (ρ) were used to study the relationship between normalised difference spectral indices (NDSIs) and the measured ecosystem properties. Finally, the effects of variable sun sensor viewing geometry on different NDSI wavelength combinations were analysed. The wavelengths with the strongest correlation to seasonal dynamics in ecosystem properties were shortwave infrared (biomass), the peak absorption band for chlorophyll a and b (at 682 nm) (GPP), the oxygen A band at 761 nm used for estimating chlorophyll fluorescence (GPP and LUE), and blue wavelengths (ρ412) (FAPAR). The NDSI with the strongest correlation to (i) biomass combined red-edge HCRF (ρ705) with green HCRF (ρ587), (ii) GPP combined wavelengths at the peak of green reflection (ρ518, ρ556), (iii) LUE combined red (ρ688) with blue HCRF (ρ436), and (iv) FAPAR combined blue (ρ399) and near-infrared (ρ1295) wavelengths. NDSIs combining near infrared and shortwave infrared were strongly affected by solar zenith angles and sensor viewing geometry, as were many combinations of visible wavelengths. This study provides analyses based upon novel multi-angular hyperspectral data for validation of Earth-observation-based properties of semi-arid ecosystems, as well as insights for designing spectral characteristics of future sensors for ecosystem monitoring.",
author = "Tagesson, {H{\aa}kan Torbern} and Rasmus Fensholt and S. Huber and Horion, {St{\'e}phanie Marie Anne F} and Idrissa Guiro and Andrea Ehammer and J. Ard{\"o}",
year = "2015",
doi = "10.5194/bg-12-4621-2015",
language = "English",
volume = "12",
pages = "4621--4635",
journal = "Biogeosciences",
issn = "1726-4170",
publisher = "Copernicus GmbH",
number = "15",

}

RIS

TY - JOUR

T1 - Deriving seasonal dynamics in ecosystem properties of semi-arid savanna grasslands from in situ-based hyperspectral reflectance

AU - Tagesson, Håkan Torbern

AU - Fensholt, Rasmus

AU - Huber, S.

AU - Horion, Stéphanie Marie Anne F

AU - Guiro, Idrissa

AU - Ehammer, Andrea

AU - Ardö, J.

PY - 2015

Y1 - 2015

N2 - This paper investigates how hyperspectral reflectance (between 350 and 1800 nm) can be used to infer ecosystem properties for a semi-arid savanna grassland in West Africa using a unique in situ-based multi-angular data set of hemispherical conical reflectance factor (HCRF) measurements. Relationships between seasonal dynamics in hyperspectral HCRF and ecosystem properties (biomass, gross primary productivity (GPP), light use efficiency (LUE), and fraction of photosynthetically active radiation absorbed by vegetation (FAPAR)) were analysed. HCRF data (ρ) were used to study the relationship between normalised difference spectral indices (NDSIs) and the measured ecosystem properties. Finally, the effects of variable sun sensor viewing geometry on different NDSI wavelength combinations were analysed. The wavelengths with the strongest correlation to seasonal dynamics in ecosystem properties were shortwave infrared (biomass), the peak absorption band for chlorophyll a and b (at 682 nm) (GPP), the oxygen A band at 761 nm used for estimating chlorophyll fluorescence (GPP and LUE), and blue wavelengths (ρ412) (FAPAR). The NDSI with the strongest correlation to (i) biomass combined red-edge HCRF (ρ705) with green HCRF (ρ587), (ii) GPP combined wavelengths at the peak of green reflection (ρ518, ρ556), (iii) LUE combined red (ρ688) with blue HCRF (ρ436), and (iv) FAPAR combined blue (ρ399) and near-infrared (ρ1295) wavelengths. NDSIs combining near infrared and shortwave infrared were strongly affected by solar zenith angles and sensor viewing geometry, as were many combinations of visible wavelengths. This study provides analyses based upon novel multi-angular hyperspectral data for validation of Earth-observation-based properties of semi-arid ecosystems, as well as insights for designing spectral characteristics of future sensors for ecosystem monitoring.

AB - This paper investigates how hyperspectral reflectance (between 350 and 1800 nm) can be used to infer ecosystem properties for a semi-arid savanna grassland in West Africa using a unique in situ-based multi-angular data set of hemispherical conical reflectance factor (HCRF) measurements. Relationships between seasonal dynamics in hyperspectral HCRF and ecosystem properties (biomass, gross primary productivity (GPP), light use efficiency (LUE), and fraction of photosynthetically active radiation absorbed by vegetation (FAPAR)) were analysed. HCRF data (ρ) were used to study the relationship between normalised difference spectral indices (NDSIs) and the measured ecosystem properties. Finally, the effects of variable sun sensor viewing geometry on different NDSI wavelength combinations were analysed. The wavelengths with the strongest correlation to seasonal dynamics in ecosystem properties were shortwave infrared (biomass), the peak absorption band for chlorophyll a and b (at 682 nm) (GPP), the oxygen A band at 761 nm used for estimating chlorophyll fluorescence (GPP and LUE), and blue wavelengths (ρ412) (FAPAR). The NDSI with the strongest correlation to (i) biomass combined red-edge HCRF (ρ705) with green HCRF (ρ587), (ii) GPP combined wavelengths at the peak of green reflection (ρ518, ρ556), (iii) LUE combined red (ρ688) with blue HCRF (ρ436), and (iv) FAPAR combined blue (ρ399) and near-infrared (ρ1295) wavelengths. NDSIs combining near infrared and shortwave infrared were strongly affected by solar zenith angles and sensor viewing geometry, as were many combinations of visible wavelengths. This study provides analyses based upon novel multi-angular hyperspectral data for validation of Earth-observation-based properties of semi-arid ecosystems, as well as insights for designing spectral characteristics of future sensors for ecosystem monitoring.

U2 - 10.5194/bg-12-4621-2015

DO - 10.5194/bg-12-4621-2015

M3 - Journal article

VL - 12

SP - 4621

EP - 4635

JO - Biogeosciences

JF - Biogeosciences

SN - 1726-4170

IS - 15

ER -

ID: 148050173