Quantitative Assessment of DESIS Hyperspectral Data for Plant Biodiversity Estimation in Australia

TL;DR

This study evaluates the effectiveness of DESIS hyperspectral satellite data in estimating plant species richness in Australia, demonstrating moderate correlation and accuracy, and supporting future biodiversity remote sensing research.

Contribution

It provides a quantitative assessment of hyperspectral data's capability to infer plant biodiversity, using multiple spectral feature extraction and regression methods.

Findings

Best model achieved r=0.71 and RMSE=5.99 in Southern Tablelands

Moderate correlation (r=0.62) in Snowy Mountains

Supports hyperspectral remote sensing for biodiversity estimation

Abstract

Diversity of terrestrial plants plays a key role in maintaining a stable, healthy, and productive ecosystem. Though remote sensing has been seen as a promising and cost-effective proxy for estimating plant diversity, there is a lack of quantitative studies on how confidently plant diversity can be inferred from spaceborne hyperspectral data. In this study, we assessed the ability of hyperspectral data captured by the DLR Earth Sensing Imaging Spectrometer (DESIS) for estimating plant species richness in the Southern Tablelands and Snowy Mountains regions in southeast Australia. Spectral features were firstly extracted from DESIS spectra with principal component analysis, canonical correlation analysis, and partial least squares analysis. Then regression was conducted between the extracted features and plant species richness with ordinary least squares regression, kernel ridge regression, and Gaussian process regression. Results were assessed with the coefficient of correlation ($r$) and Root-Mean-Square Error (RMSE), based on a two-fold cross validation scheme. With the best performing model, $r$ is 0.71 and RMSE is 5.99 for the Southern Tablelands region, while $r$ is 0.62 and RMSE is 6.20 for the Snowy Mountains region. The assessment results reported in this study provide supports for future studies on understanding the relationship between spaceborne hyperspectral measurements and terrestrial plant biodiversity.