Links between Solar-Induced chlorophyll Fluorescence and isoprenoid emissions from field spectroscopy in low Arctic tundra

As climate warming is expected to extend the growing season and enhance vegetation productivity in the Arctic, a consequent increase in emissions of Biogenic Volatile Organic Compounds (BVOC) is forecasted.

Isoprenoid emissions are known to be driven, among other factors, by photosynthetic processes. Our hypothesis is then that the emissions of particularly isoprenoids can be linked to remotely sensed proxies of photosynthetic activity in typical vegetation of low Arctic tundra.

We tested this hypothesis by examining the relationship between Solar-Induced chlorophyll Fluorescence (SIF) in the O2-A absorption band and BVOC emission rates in a field spectroscopy framework, to further investigate the relationship between the reflectance properties of vegetation and total BVOC/isoprenoid emission rates. The study site is located in the area of Kobbefjord, Greenland.

The results of our analysis demonstrate that SIF and other spectral indices (Enhanced Vegetation Index – EVI, Photochemical Reflectance Index – PRI, MERIS Terrestrial Chlorophyll Index – MTCI) explain a substantial share of the variation in isoprenoid and total BVOC emissions. These findings can potentially be of aid in opening new avenues to model BVOC emissions at larger scales, as SIF and other relevant indices can be directly derived from new-generation UAV and satellite imagery.