Comparison of two methods for indirect measurement of atmospheric dust deposition: Street-dust composition and vegetation-health status derived from hyperspectral image data

Abstract

This study presents a statistical comparison between the in situ measurements of the elemental composition of street dust and a forest health status classification derived from aerial hyperspectral image data (HyMap). Combining these two methods allowed us to indirectly pinpoint at a high spatial resolution the atmospheric dust emissions and its effects in a study area around the open-pit lignite mine in Sokolov, Czech Republic. The results reveal a statistically significant relationship between increased Al, Na, Li and Sr levels in street dust and decreased forest health status, and the highest number of statistically significant correlations within a 100 m distance from the street-dust sampling points. Differences in lithological composition were unable to sufficiently explain these changes, therefore anthropogenic factors like dust emissions from coal mining and coal combustion, as well as urbanisation and other industries might be the reason for this link. Such studies are a crucial step in developing new high spatial resolution methods for determining atmospheric dust deposition and their effects.

Keywords: Coal mining; Dust emissions; Forest health; Hyperspectral imaging; Remote sensing; Street dust.

Fig. 1

The study area. 1—quaternary deposits; 2—consolidated Cenozoic sedimentary rocks; 3—mafic igneous rocks; 4—felsic igneous rocks; 5—volcanic- and quartz-rich metamorphic rocks; 6—highly metamorphic rocks; 7—low metamorphic rocks; 8—populated areas; 9—open-pit lignite mines (active and abandoned); 10—highway; 11—rivers; 12—larger industrial facilities; 13—street-dust sampling points; 14—area of Norway Spruce health status measurements

Fig. 2

Scaling of Al and Na levels in street dust and average Norway Spruce Health status 100 m around street-dust sampling points in the Sokolov basin

Fig. 3

Spatial distribution of Norway Spruce health status with general trend (polynomial regression), Na, Al and Li levels in street dust. 1—populated areas; 2—abandoned and active lignite open pits; 3—highway; 4—rivers; 5—street-dust sampling points; 6—larger industrial facilities; 7—Norway Spruce health status measurement area