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Estimation of chlorophyll content and the leaf area index (LAI) using remote sensing technology is of particular use in precision agriculture. Wavelengths at the red edge of the vegetation spectrum (705 and 750 nm) were selected to test vegetation indices (VIs) using spaceborne hyperspectral Hyperion data for the estimation of chlorophyll content and LAI in different canopy structures. Thirty sites were selected for the ground data collection. The results show that chlorophyll content and LAI can be successfully estimated by VIs derived from Hyperion data with a root mean square error (RMSE) of 7.20-10.49 μg cm-2 for chlorophyll content and 0.55-0.77 m2 m-2 for LAI. The special index derived from three bands provided the best estimation of the chlorophyll content (RMSE of 7.19 μg cm-2 for the Modified Chlorophyll Absorption Ratio Index/Optimized Soil-Adjusted Vegetation Index (MCARI/OSAVI705)) and LAI (RMSE of 0.55 m2 m-2 for a second form of the MCARI (MCARI2705)). These results demonstrate the possibilities for analysing the variation in chlorophyll content and LAI using hyperspectral Hyperion data with bands from the red edge of the vegetation spectrum. [ABSTRACT FROM AUTHOR]

In recent years, the areas damaged by the East Asia migratory locust plagues (Locusta migratoria manilensis) have enlarged geographically in China. Some outbreaks in parts of the Dagang region, in the east coast of China, have caused drastic reductions in the yield of agricultural reeds and have created a severe threat to local and regional agriculture. Currently, the monitoring system for this species depends on field observations conducted by sparsely distributed observing stations established in the 1950s. This observation network was. in the past, successfully operated to identify major locust outbreaks. However, due lo the expansion of infestation areas and the increase of locust density, spatial information technology was needed to establish a satellite sensor-based monitoring system for the East Asia migratory locust plagues. This Letter outlines the preliminary experimental work conducted in 2001 for a feasibility study in establishing a sensor-based locust monitoring system. In this experiment, sample statistics of biomass and leaf area index (LAI) from the affected and non-affected areas by locusts were calculated, and the spectra of field reed samples from both areas were also evaluated together with synchronous Landsat Enhanced Thematic Mapper (ETM+) multi-spectral data. The study showed that satellite sensors may be used operationally to monitor locust damage. [ABSTRACT FROM AUTHOR]