Satellite monitoring of prairie wetlands

Satellite monitoring of prairie wetlands has advanced rapidly, providing comprehensive tools for mapping, inventorying, and monitoring the dynamic prairie wetland ecosystems, especially in the Prairie Pothole Region (PPR). Current technologies utilize multi-temporal optical and radar satellite imagery combined with elevation data and advanced machine learning techniques to capture the highly variable conditions of these wetlands^{[1][2][3][4][5]}.

Key methods and findings:

• Multi-sensor satellite imaging: The primary satellites used are Sentinel-1 (Synthetic Aperture Radar - SAR) and Sentinel-2 (optical imagery). Combining radar and optical data addresses varying water levels, vegetation, and cloudy periods, while LiDAR adds critical elevation and structural data^[3][4][5].
• Temporal (time-series) analysis: Wetlands in the prairie regions are highly dynamic, experiencing frequent flooding and drying cycles that can only be captured by analyzing satellite images over multiple seasons and years^[6][3][4]. This approach allows mapping of the hydroperiod (flooding frequency and duration), which is essential for classifying wetland types and permanence^[4].
• Automated classification and mapping: Machine learning and deep learning models trained on multi-temporal, multi-sensor satellite datasets enable identification and delineation of diverse wetland classes (e.g., pothole marshes, shallow open water) with high spatial detail^[3][4]. Detailed inventories can achieve ~95% overall accuracy in differentiating wetland and upland areas; however, distinguishing between specific wetland types can be more challenging, especially for ephemeral or very shallow wetlands^[4].
• Operational frameworks: Platforms like Google Earth Engine facilitate scalable processing and visualization, while dedicated applications (e.g., Wetland Explorer) provide users with up-to-date, interactive wetland maps^[3][4].

Key applications:

• Wetland inventory and status assessment: Satellite data help create comprehensive wetland inventories, surpassing previous field and aerial methods, especially for the numerous small, scattered, and ephemeral wetlands typical of the PPR^[4][7].
• Change detection and management: Monitoring seasonal and interannual fluctuations in wetland water levels supports the assessment of wetland loss, degradation, or recovery in response to climate, agriculture, and conservation initiatives^[8][3][9].
• Ecological and hydrological research: Hydroperiod mapping helps assess wetland function, biodiversity support, and flood mitigation capacity across large and remote regions^[1][4].

Limitations and Considerations:

• Small, temporary wetlands: Although fine-resolution segmentation (down to 2 m) and dense time series improve detection, very small or short-lived wetlands remain underdetected or misclassified in some cases^[4][5].
• Validation: Field validation is still needed for rigorous accuracy assessment, especially due to changing water levels and overlapping classes (e.g., shallow open water vs. marsh)^[4].
• Data gaps: Persistent cloud cover can limit optical data availability; radar can partly compensate, but integration is necessary for best results^[3][5].
• Landscape complexity: Prairie wetlands' high spatial variability and anthropogenic influences (e.g., drainage for agriculture) add complexity to long-term monitoring efforts^[8][3][4].

In summary, satellite monitoring is now an essential, scalable, and cost-effective approach for tracking prairie wetlands. The integration of multi-temporal, multi-sensor satellite data—analyzed with advanced computational methods—enables precise mapping of wetland dynamics and supports better conservation and management decisions, although ongoing field-calibration and methodological refinements are needed^[1][3][4].

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• https://www.mdpi.com/2072-4292/13/19/3878   
• https://opus.uleth.ca/items/c7904878-3e24-4738-a016-b043772aaf66 
• https://dataspace.copernicus.eu/gallery/2020-6-25-wetland-monitoring-canada         
• https://www.mdpi.com/2072-4292/14/14/3401             
• https://www.sciencedirect.com/science/article/abs/pii/S0341816212000471    
• https://abmi.ca/publication/613 
• https://www.ducks.ca/initiatives/canadian-wetland-inventory/ 
• https://wetland-report.abmi.ca/atlas-home/2.0-Alberta-Wetlands/2.3-Wetlands-Prairie-Region.html  
• https://phjv.ca/science-and-planning/habitat-monitoring/