Author
Hunt Jr, Earle | |
FAHNESTOCK, J. - UNIVERSITY OF WYOMING | |
KELLY, ROBERT - UNIVERSITY OF WYOMING | |
WELKER, JEFFREY - UNIVERSITY OF WYOMING | |
REINERS, WILLIAM - UNIVERSITY OF WYOMING | |
SMITH, WILLIAM - WAKE FOREST UNIVERSITY |
Submitted to: Remote Sensing Lab Spectroscopy to Remotely Sensed Spectra of Soils Plant
Publication Type: Book / Chapter Publication Acceptance Date: 10/1/2002 Publication Date: N/A Citation: N/A Interpretive Summary: Aircraft measurements of carbon dioxide exchange rates (resulting from photosynthesis and respiration) were acquired in 1999 over four southeastern Wyoming landscapes: a coniferous forest, a mixed dryland/irrigated agricultural area, a mixed-grass prairie, and a sagebrush steppe. A linear relationship between net carbon exchange rate and the amount of absorbed light was used to determine the efficiency of radiation use. This allows the use of weather satellite data to locate areas that are net sinks of carbon dioxide from the air or net sources of carbon dioxide to the air. The sagebrush and forest sites were net carbon sinks, whereas the grassland and agricultural sites were in carbon balance. With large areas of the globe covered by rangelands, the potential for carbon sequestration may be significant. Technical Abstract: Aircraft eddy flux measurements of net ecosystem exchange were acquired in 1999 over four southeastern Wyoming landscapes: a coniferous forest, a mixed dryland/irrigated agricultural area, a mixed-grass prairie, and a sagebrush steppe. A linear relationship between net ecosystem exchange and the absorbed photosynthetically active radiation was used to determine the efficiency of radiation use, which was used with remotely-sensed normalize difference vegetation index to calculate gross primary production. Chamber measurements of total ecosystem respiration for the sagebrush and grassland sites were used to develop a functional relationship with daily average temperature. The sagebrush and forest sites were net carbon sinks, whereas the grassland and agricultural sites were in carbon balance. Combining the use of remote sensing with net ecosystem exchange measurements avoids problems associated with small-scale flux sampling to determine areas of carbon sequestration. With large areas of the globe covered by rangelands the potential for carbon sequestration may be significant. |