Category: Identifying Invasive Species Extent & Critical Species Habitat
Project Team: Northern Great Plains Ecological Forecasting
Team Location:åÊNASA Goddard Space Flight Center ÛÒ Greenbelt, Maryland
Dr. Kenton Ross (NASA Langley Research Center)
Sean McCartney (Center Lead)
Cheatgrass (Bromus tectorum) and Japanese brome (Bromus japonicus) are widespread invasive annual brome grasses that are distributed throughout the western United States. In the Northern Great Plains (NGP), the presence of these invasive brome species has led to a decrease in native plant diversity, reduced soil water content, and altered fire regimes—leading to more frequent fires of higher intensity. The National Park Service Northern Great Plains Network (NGPN) Inventory & Monitoring Program conducts vegetation monitoring throughout national park units to develop management practices for habitat restoration and invasive species control. Incorporating remotely sensed NASA Earth observations data enables the NGPN to efficiently monitor the regional extent of brome abundance over time. The spatial and temporal resolution of Aqua/Terra Moderate Resolution Imaging Spectroradiometer (MODIS), Landsat 8 Operational Land Imager (OLI), Landsat 5 Thematic Mapper (TM), and Sentinel-2 Multispectral Instrument (MSI) were leveraged to capture the vegetation phenology of these invasive brome species across the NGP.
The satellite-derived Normalized Difference Vegetation Index (NDVI) was used to determine the distinct and early green up and senescence patterns of brome. Using unsupervised classification methods, the invasive bromes were identified from the surrounding native grassland species and associations were made between brome abundance and NDVI phenology metrics. Understanding the behavior of these invasive species through space and time will aid managers in developing a successful annual brome management strategy for NGP park units and identify areas for targeted management efforts.