Landscape-scale forest restoration decreases vulnerability to drought mortality under climate change in southwest USA ponderosa forest
Lisa A. McCauley, John. B. Bradford, Marcos D. Robles, Robert K. Shriver, Travis J. Woolley, Caitlin A. Andrews
Climate Change, Fire, Forest Restoration Benefits
Drought is projected to increase tree mortality in many western US forests due to climate change and could result in large-scale tree die-offs, altering forest composition and ecosystem services. Tree mortality has also been found to be higher in forests with greater tree density. Southwestern US forests are particularly susceptible to increased tree mortality due to the predicted temperature increases, drier soils, and forests with high tree density. The goal of this study was to examine how the Four Forests Restoration Initiative (4FRI), a large-scale forest restoration currently being implemented to reduce the risk of severe wildfire, will affect ponderosa pine mortality under climate change. We found that without thinning, mid-century changes in climate could increase annual ponderosa pine mortality rates by 45–57% over contemporary rates. However, with 4FRI thinning, mid-century mortality was predicted to remain near or below contemporary rates and these rates are 31–35% less than the mid-century scenarios without thinning. Our study shows that while climate change is likely to increase tree mortality rates, large-scale forest restoration projects, such as 4FRI, have the potential to ameliorate the effects of climate change and keep mortality rates near contemporary levels for decades.
Aerial view of the Parks West restoration site overseen by TNC. Taken March 16, 2020.
Conservancy staffers, Dale Turner and Amanda Rebore, helping to map the Sabn Pedro River in Arizona. They use a GPS unit to denote the end of the water flow on the LowerSan Pedro River. They hiked through the Conservancy’s San Pedro Preserve.
Our Approach to Science
The Nature Conservancy’s conservation science program in Arizona engages stakeholders and expertise in applied science and policy to develop new information, ideas, and tools that can help solve some of our most pressing challenges affecting people and nature
Explore Our Science
We are working with partners and stakeholders to accelerate the pace and scale of forest restoration for a healthy Arizona
Mapping the Status of River Streams
Wet/dry mapping provides a low-cost, river-wide snapshot of hydrologic conditions for rivers with interrupted perennial surface flows.
Every June groups of volunteers walk the entire 170 mile length of the San Pedro River and record where it is wet and where it is dry during the hottest, driest time of the year. Twenty years’ worth of data on summertime surface flows in the San Pedro River within the San Pedro Riparian National C[…]
Arizona, Geo Region
Forest Restoration Benefits, Topic
Jamie L Peeler, Lisa McCauley, Kerry L Metlen, Travis Woolley, Kimberley T Davis, Marcos D Robles, Ryan D Haugo, Karin L Riley, Philip E Higuera, Joseph E Fargione
Identifying opportunity hot spots for reducing the risk of wildfire-caused carbon loss in western US conifer forests
As both the climate and wildfire crises intensify and investments are made to dramatically increase the pace of forest restoration across dry forests in the western U.S. through the Wildfire Crisis Strategy, an understanding of where Nature-Based Solutions are the most optimal in lessening climate i[…]
Arizona, Colorado River Basin, Western U.S.
Climate Change, Forest Restoration Benefits
Collaboration, USDA ARS
Ravindra Dwivedi, Joel A. Biederman, Patrick D. Broxton, Kangsan Lee, Willem J.D. van Leeuwen, Jessie K. Pearl
Forest density and snowpack stability regulate root zone water stress and percolation differently at two sites with contrasting ephemeral vs. stable seasonal snowpacks
Much of the western United States depends on high elevation snowpack in forested watersheds for water supply, wildlife habitat, and recreation in both adjacent and downstream communities. The forest-snow-water relationship is well studied in areas with stable – that is, cold – seasonal s[…]