Modeling winter wheat phenology and carbon dioxide fluxes at the ecosystem scale based on digital photography and eddy covariance data

Abbreviations: GPP, gross primary production; LUE advanced very high-resolution radiometer; MODIS, spectroradiometer; NEE, net ecosystem exchange; APA radiation absorbed; VPM, vegetation photosynthesis m region of interest. ☆ This is an open-access article distributed under the t Attribution-NonCommercial-NoDerivativeWorks License, use, distribution, and reproduction in anymedium, provide are credited. ⁎ Corresponding author. Tel.: +86 10 6488 9599; fax E-mail address: [email protected] (H. He).