Ecological Forestry & DoD’s Carbon Footprint
The Department of Defense (DoD) strives for ecologically sustainable management of its forests to maintain desired ecosystem services, including realistic training settings, native biological diversity, and carbon storage. In a carbon-constrained world, how DoD manages its forested land base will determine whether alternative land use and silvicultural practices within these ecosystems will be a positive or negative contribution to an installation’s overall carbon footprint.
SERDP initiated a suite of four projects in FY 2011 focused on developing the fundamental and applied science required to manage and restore forested ecosystems on DoD lands in accordance with the principles of ecological forestry, a silvicultural approach that perpetuates ecosystem integrity at landscape spatial scales while continuing to provide wood products and other ecosystem services. These projects are investigating the interactions between ecological forestry-based silvicultural prescriptions and carbon management in the context of maintaining other desired ecosystem services.
Information on the carbon cycle is available for certain forest types and at differing spatial scales. Ultimately, however, DoD needs refined information at appropriate spatial scales that is applicable to the forest types it manages and the silvicultural prescriptions it applies. Another consideration, especially in the Southeast, is that DoD-managed forests are transitioning from a commercial plantation forest model to a more natural stand model that favors native species and restoration of historic structure and ecological processes. It is important to understand the carbon cycle changes that will occur and the potential effects on DoD’s carbon footprint as these forest transitions progress.
Forest restoration in the south-central United States typically involves thinning of the overstory and re-introduction of surface fires, resulting in an open pine-oak savanna that was historically common across much of the region. These treatments cause a shift in ecosystem productivity from the overstory trees to a vigorous grass and forb understory that is beneficial to many wildlife species. This shift in the plant community also changes the carbon dynamics from largely aboveground to largely belowground sequestration. In the SERDP project Statistically Rigorous Carbon Stock Predictions of Forest Restoration in the Southern United States (RC-2116), Dr. Duncan Wilson of Oklahoma State University and his team are developing a mechanistic model that describes how carbon sequestration changes in a newly restored savanna. The field calibration and statistical approaches to estimating carbon stocks will be directly transferable to other forested lands.
For the longleaf pine ecosystem in particular, modeling tools and basic information at the ecosystem level are needed to assess how restoration and management practices, in particular prescribed fire, impact carbon pools over time and under a range of soils and stand structures. As part of SERDP project Developing Tools for Ecological Forestry and Carbon Management in Longleaf Pine (RC-2115), Dr. Lisa Samuelson and her team at Auburn University are developing and coupling forest carbon cycle models that simulate the range of management activities that occur on DoD installations, with a focus on the transition between even-age and uneven-age stand management, across the longleaf pine range. The suite of simulations will demonstrate how land use practices and silvicultural prescriptions influence the life-cycle carbon balance of longleaf pine ecosystems, biodiversity, and sustained ecological yield of forest products over short, intermediate, and long horizons.
Although forest carbon sequestration can be used to mitigate changing climatic conditions, sequestering carbon in forests carries a risk that disturbance will revert this carbon back to the atmosphere. In fire-prone forests, carbon reversal risk can be mitigated using ecologically based silvicultural prescriptions. Through SERDP project Modeling the Carbon Implications of Ecologically Based Forest Management (RC-2118), Dr. Matthew Hurteau of Northern Arizona University and his team are developing a methodology for modeling forest carbon sinks and sources on DoD lands that can be used to quantify the carbon impacts of different forest management regimes, including those directed toward reducing fire emissions.
In a novel approach, under SERDP project Developing Novel Ecosystems that Enhance Carbon Storage, Native Biodiversity, and Human Mobility in Lowland Hawaiian Forests (RC-2117), Dr. Rebecca Ostertag of the University of Hawaii and her team are developing and evaluating a set of "hybrid ecosystems" in which a mix of native and non-native species maintain valuable forest structure and ecosystem services. The introduction and establishment of non-native species is so pervasive in the Hawaiian Islands that often it is not possible, economically or practically, to return to all-native ecosystems. Some non-native species, however, may be playing important roles in the community in terms of providing ecosystem goods and services. Utilizing ecological assembly rules and species-level information, these researchers are designing combinations of species that balance trade-offs between supporting native biodiversity and providing for carbon storage and military training environments.
The knowledge and products collectively generated by these SERDP research efforts will enable DoD managers to better determine appropriate objectives for carbon management that ensure compatibility with maintaining other desired ecosystem services, supporting the military mission, and maintaining native biological diversity.
- SERDP and ESTCP Ecological Forestry Featured Initiative
- Developing Novel Ecosystems that Enhance Carbon Storage, Native Biodiversity, and Human Mobility in Lowland Hawaiian Forests
- Modeling the Carbon Implications of Ecologically Based Forest Management
- Statistically Rigorous Carbon Stock Predictions of Forest Restoration in the Southern United States
- Developing Tools for Ecological Forestry and Carbon Management in Longleaf Pine