Delta-X: Fractional Vegetation Cover for Louisiana Wetlands

AVIRIS-NG imagery from 2021 was processed using linear spectral unmixing to estimate fractional cover of green vegetation, non-photosynthetic vegetation, and soil across the Atchafalaya and Terrebonne basins in Louisiana. The analysis combined airborne hyperspectral data with in situ field spectra from the USGS Spectral Library (v7) and ground-level GoPro images. Outputs provide pixel-level fractional composition values scaled from 0 to 1.

Use Cases

• Monitoring wetland health and vegetation succession based on fractional cover estimates.
• Validating ecosystem and biogeochemistry models using spatially explicit vegetation and soil fractions.
• Assessing land cover change in deltaic systems using the 2021 geospatial time slice.
• Calibrating other remote sensing products with high-fidelity spectral unmixing results.

Strengths

• Integrates multiple data sources: AVIRIS-NG airborne imagery, USGS in situ spectral library (v7), and coincident ground imagery.
• Provides specific fractional estimates for three distinct endmembers: green vegetation, non-photosynthetic vegetation, and soil.
• Applies a detailed processing chain including atmospheric correction and BRDF adjustment.

Limitations

• Column names and dataset size (row count, file size) are unspecified across all sources.
• Conflicting update dates: one source lists 2026-04-10, another lists 2021-09-25, creating uncertainty about data currency.
• License is ambiguously listed as 'other-license-specified' without further details.

Provenance

Source

National Aeronautics and Space Administration

Collection Method

Linear spectral unmixing applied to atmospherically corrected, BRDF-adjusted AVIRIS-NG surface reflectance mosaics, using a compiled spectral library.

Time Range

2021

Freshness

2026-04-10 (from datagov), but conflicting with 2021-09-25 (from nasa_earthdata).

Geography

Atchafalaya and Terrebonne basins, Mississippi River Delta (MRD), Louisiana, USA