Crop Coefficients Derived from Reflected Canopy Radiation: A Concept

摘要: ABSTRACT SIMILARITIES between the crop coefficient curve and a vegetation index showed potential for modeling into coefficient. Therefore, possibility of directly estimating from measured reflectance properties crop/soil scene was investigated. Reflected canopy radiation in 0.63 to 0.69 jwm 0.76 0.90 jjim band widths normal two meters above corn (Zea mays L.), normalized difference (ND) computed. The seasonal ND curvilinear resembled basal (K^b) corn. Leaf area shading were 3.2 77.6%, respectively, when reached its maximum valvue. A linear transformation developed by equating at effective cover dry, bare soil experimental site K^b dry evaporation, respectively. This produced very similar named spectral (K^J. Crop coefficients derived measurements are independent usual time base parameters, planting date date, associated with traditional coefficients. Thus, is real-time that permits express response weather, management practices, stresses.