Abstract
Extensive studies have focused on assessing leaf chlorophyll content through spectral indices; however, the accuracy is weakened by limited wavebands and coarse resolution. With hundreds of wavebands, hyperspectral data can substantially capture the essential absorption features of leaf chlorophyll; however, few such studies have been conducted on same species in various degraded vegetations. In this investigation, complete combinations of either original reflectance or first‐order derivative spectra we conducted a complete combination on either original reflectance or its first‐order derivative value from 350 to 1000 nm to quantify leaf total chlorophyll (Chll), chlorophyll‐a (Chla), and chlorophyll‐b (Chlb) contents. This was performed using three hyperspectral datasets collected in situ from lightly, moderately, and severely degraded vegetations in temperate Helin County, China. Suitable combinations were selected by comparing the numbers of significant correlation coefficients with leaf Chll, Chla, and Chlb contents. The combinations of reflectance difference (D ij), normalized differences (ND), first‐order derivative (FD), and first‐order derivative difference (FD(D)) were found to be the most effective. These sensitive band‐based combinations were further optimized by means of a stepwise linear regression analysis and were compared with 43 empirical spectral indices, frequently used in the literature. These sensitive band‐based combinations on hyperspectral data proved to be the most effective indices for quantifying leaf chlorophyll content (R 2 > 0.7, p < 0.01), demonstrating great potential for the use of hyperspectral data in monitoring degraded vegetation at a fine scale.
Highlights
One-third of earth’s continents are covered by degraded land, with various intensities of vegetation degradation (FAO, 2014)
It can reasonable to deduce that hyperspectral indices developed on narrow bands sensitive to leaf Chll content could perform better than empirical spectral indices solely based on several bands
The complete combinations of reflectance and its first-order derivative value across the entire band acquired by the ASD spectrometer were constructed
Summary
One-third of earth’s continents are covered by degraded land, with various intensities of vegetation degradation (FAO, 2014). The monitoring of degraded vegetation is an important issue for grazing management, the identification of conservation area, ecological restoration of degraded land across the globe. This requires an accurate and fast estimation of plant physiological parameters at multiple scales (Yuan et al, 2011; Xia et al, 2014). | 7069 and assessment of the overall health of the vegetation, indicating its degradation status (Gottardini et al, 2014; Peng et al, 2014) This will allow us to conduct restoration and revegetation actions where they are required. It can reasonable to deduce that hyperspectral indices developed on narrow bands sensitive to leaf Chll content could perform better than empirical spectral indices solely based on several bands
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
