Enhanced optical sensing methods:
From the article
New interpretations of established optical sampling methods, including the photochemical reflectance index (PRI) and solar-induced chlorophyll fluorescence (SIF),are discussed within the context of the LUE model. Multi-scale analysis across temporal and spatial axes is a central theme because such scaling can provide links between eco-physiological mechanisms detectable at the level of individ-ual organisms and broad patterns emerging at larger scales,enabling evaluation of emergent properties and extrapolationto the flux footprint and beyond. Proper analysis of the sampling scale requires an awareness of sampling context thatis often essential to the proper interpretation of optical sig-nals. Additionally, the concept of optical types, vegetation exhibiting contrasting optical behavior in time and space, is explored as a way to frame our understanding of the controls on surface–atmosphere fluxes. Complementary normalized difference vegetation index (NDVI) and PRI patterns across ecosystems are offered as an example of this hypothesis, with the LUE model and light-response curve providing an integrating framework. Experimental approaches allowing systematic exploration of plant optical behavior, particularly in the context of the flux tower network, provides a unique way to improve our understanding of environmental constraints and ecophysiological function. In addition to an enhanced mechanistic understanding of ecosystem processes, this integration of remote sensing with flux measurements offers many rich opportunities for upscaling, satellite validation, and informing practical management objectives ranging from assessing ecosystem health and productivity to quantifying biospheric carbon sequestration.
Read the open access article here: https://digitalcommons.unl.edu/natrespapers/777/