학술논문

Accounting for non-photosynthetic vegetation in remote-sensing-based estimates of carbon flux in wetlands.
Document Type
Article
Source
Remote Sensing Letters. Jun2013, Vol. 4 Issue 6, p542-551. 10p.
Subject
*WETLANDS monitoring
*WETLAND biodiversity
*CARBON sequestration
*CLIMATE change mitigation
*PHOTOSYNTHETICALLY active radiation (PAR)
*PRIMARY productivity (Biology) measurement
*CHLOROPHYLL analysis
*LIGHT transmission
Language
ISSN
2150-704X
Abstract
Monitoring productivity in coastal wetlands is important due to their high carbon sequestration rates and potential role in climate change mitigation. We tested agricultural- and forest-based methods for estimating the fraction of absorbed photosynthetically active radiation (fAPAR), a key parameter for modelling gross primary productivity (GPP), in a restored, managed wetland with a dense litter layer of non-photosynthetic vegetation, and we compared the difference in canopy light transmission between a tidally influenced wetland and the managed wetland. The presence of litter reduced correlations between spectral vegetation indices andfAPAR. In the managed wetland, a two-band vegetation index incorporating simulated World View-2 or Hyperion green and near-infrared bands, collected with a field spectroradiometer, significantly correlated withfAPARonly when measured above the litter layer, not at the ground where measurements typically occur. Measures of GPP in these systems are difficult to capture via remote sensing, and require an investment of sampling effort, practical methods for measuring green leaf area and accounting for background effects of litter and water. [ABSTRACT FROM AUTHOR]