Hyperspectral spectroscopy provides the opportunity to estimate key ecosystem traits beyond those derived from traditional remote sensing techniques due to the increased spectral resolution. The HyspIRI project attempts to make measurements of ecosystem metabolism, and we hope to characterize variations in metabolism across a landscape due to climate and species composition.

We are using imaging spectroscopy (AVIRIS) and thermal imagery (MASTER) to estimate two key parameters of photosynthesis: the maximum rate of RuBisCO carboxylation (Vcmax) and the maximum rate of electron transport/RuBP regeneration (Jmax). These two parameters are traditionally determined via gas exchange measurements, but recent work has enabled us to estimate them with leaf spectroscopy by linking leaf-level spectroscopy with leaf-level gas exchange measurements.

A big challenge for the project is scaling leaf-level measurements of Vcmax/Jmax to a canopy level, and linking AVIRIS estimates of Vcmax/Jmax with our ground level measurements.

The study sites comprise key agricultural canopies and two climate-elevation gradients, which span broad vegetation types from desert chaparral to oak woodlands and closed canopy needle-leaf forests.

See also HyspIRI Flux Tower Project

Collaborators

• Ankur Desai
• Mike Goulden
• Eric Kruger
• Shawn Serbin
• Dar Roberts
• Susan Ustin