PROVE Land Cover and Leaf Area of Jornada Experimental Range, New Mexico, 1997

During the NASA Earth Observing System Prototype Validation Exercise (PROVE) at the Jornada Experimental Range, New Mexico, on May 20-30, 1997, we calculated plot-level plant area index, leaf area index, total fractional cover, and green fractional cover with data from four instruments: (1) a Dycam Agricultural Digital Camera (ADC), (2) a LI-COR LAI-2000 plant canopy analyzer, (3) a Decagon sunfleck ceptometer, and (4) a laser altimeter.

Estimates from the LAI-2000 and ceptometer were very similar (plant area index 0.3, leaf area index 0.22, total fractional cover 0.19, green fractional cover 0.14), but the ADC produced values 5 to 10% higher. Laser altimeter values, depending on the height cutoff used to establish total fractional cover, were either higher or lower than the other instruments' values: a 10-cm cutoff produced values approximately 80% higher, whereas a 20-cm cutoff produced values approximately 30% lower.