Lately I’ve been working with some forest service hydrologists to predict increased water availability resulting from longleaf pine management. This is part of a larger effort to make proposals to national programs from the South Atlantic region more competitive. More and more national programs that fund protection, restoration, and management are including water-related impacts in their scoring criteria. Being able to predict millions of gallons of water per day saved as a result of proposals from the South Atlantic could help make those proposals more competitive and result in more on-the-ground conservation.

The models I’m using are pretty simple and are based on climate and mass balance equations used in the Water Supply Stress Index ecosystem services model (WaSSI). The predictions are based on the changes in leaf area when going from unburned overgrown longleaf to regularly burned longleaf. More leaf area in unburned stands means more evapotranspiration and less water available.

The tricky part is that the models need estimates of the Leaf Area Index (LAI). Unlike DBH, LAI is not a commonly collected metric. There is a 1km GIS based layer available but it’s too coarse to get at stand-level numbers. Based on an literature/internet search, I have some stand level data on regularly burned longleaf in North Florida and Southwest Georgia but nothing in South Carolina, North Carolina, or Virginia. I don’t have any LAI data for regularly burned shortleaf pine savannah. If you know of anyone that might have LAI data on longleaf/shortleaf, or have some yourself, please send me an email at rua@southatlanticlcc.org.