Water stress represents a common mechanism for many of the primary disturbances affecting forests, and forest management needs to explicitly address the very large physiological demands that vegetation has for water. This study demonstrates how state-of-science ecohydrologic models can be used to explore how different management strategies might improve forest health.
Widespread threats to forests due to drought stress prompt re-thinking of priorities for water management on forest lands. In contrast to the widely held view that forest management should emphasize providing water for downstream uses, we argue that maintaining forest health in the face of environmental change may require focusing on the forests themselves and strategies to reduce their vulnerability to increasing water stress in the context of a changing climate. Management strategies would need to be tailored to specific landscapes but could include: a) thinning; 2) encouraging drought-tolerant species; 3) irrigation; and 4) strategies that make more water available to plants for transpiration. Hydrologic modeling reveals that specific management actions could reduce tree mortality due to drought stress. Adopting water conservation for vegetation as a priority for managing water on forest lands would represent a fundamental change in perspective and potentially involve tradeoffs with other downstream uses of water.
Emrys Treasure, Mary Morrison, John Cleeves, Kristen Schmitt
Project process and implementation:
Forest Plan Revision under the 2012 Planning Rule is an iterative process that includes three general phases – 1) assessment; 2) developing, amending or revising the forest plan, and; 3) implementation and monitoring (see fig 1). The plan revision is currently in progress on the Francis Marion, and materials are revised as new information and public input become available. See the Francis Marion Plan Revision webpage for the most current information.
At each of these three phases, there are opportunities to consider climate change, how it will affect forest resources on the Francis Marion, and how to develop appropriate management responses and monitoring efforts. In order to base these climate change considerations on the best available science, the Francis Marion partnered researchers and used TACCIMO for knowledge management. TACCIMO is a web-based information delivery tool that was developed by the Southern Research Station (SRS) Eastern Forest Environmental Threat Assessment Center (EFETAC) and the Forest Service’s Southern Region (R8) to connect climate change science with forest management and planning needs. The TACCIMO support team works directly with national forests on a variety of planning efforts, and these collaborations help TACCIMO tool evolve over time. The forests in the Southern Region are among the first to directly incorporate climate change into their forest plan revisions using the new 2012 Planning Rule, and the TACCIMO team, along with other FS and partner scientists, are supporting these efforts and assisting in interpreting relevant best available scientific information. Members of the TACCIMO team have attended forest planning meetings and presented at public fora on the forest plan revision for the Francis Marion.
Figure 1: A diagram illustrating the three phases of the Forest Plan Revision process
Phase 1: Assessment Draft Assessment Development The assessment for a forest plan revision is designed to rapidly evaluate existing information about relevant ecological, economic, and social conditions and trends, and their context within the broader landscape. TACCIMO reports capturing findings from current and relevant climate change scientific literature was reviewed by the Francis Marion planning team and integrated into the assessment phase of the plan revision process. The planning team also used TACCIMO summaries developed from the Climate Change Tree Atlas to look at future suitable habitat for different tree species, and the Sea Level Rise Affecting Marshes Model (SLAMM) model to examine sea level rise. The draft assessment for the Francis Marion is open for review and input until late 2014.
A small sample of key findings on climate change that were integrated into the Francis Marion assessment include:
Sea level rise and extreme weather - The rate of sea level rise is expected to increase over the next century, as is the potential for severe storms such as hurricanes. Together, these changes could have large consequences for the coastal ecosystems that occur where the FMNF borders the Atlantic Ocean. Ecosystems like maritime forests, saltwater marshes, and tidally influenced riparian zones may be particularly threatened. Sea level rise will also increase the potential for saltwater intrusion into coastal freshwater tables, which could affect groundwater resources.
Synergy between adaptation and restoration goals - Some plant and animal species are expected to do better than others as the climate changes. For example, longleaf pine ecosystems tend to be more tolerant of stressors such as drought, insects, and wind damage, and science suggests that they may be well-suited to future conditions. An ongoing effort on the Francis Marion is restoring native ecosystems and species, including longleaf pine ecosystems which were once dominant across the southeastern U.S. but have lost ground to other species such as loblolly pine. In this situation, forest restoration efforts could have the added benefit of making the forests on the FMNF more resilient to changing climate.
Invasive Species - With a changing climate, invasive species may outcompete or negatively affect native species. Certain invasive plant species such as cogongrass are able to tolerate a wide range of harsh conditions, and have the potential to increase on the FMNF, which could alter entire forest ecosystems. The FMNF is located close to a major harbor that gets shipping traffic from around the world, so the potential for new introductions is also high.
Draft Preliminary Need to Change The Draft Preliminary Need to Change represents the transition from the assessment to the forest plan development phase. It evaluates the existing forest plan in light of new scientific information, laws, and policies, and identifies plan directions that “need to change.” Comments and questions on the draft are being accepted.
Notably, there is no direction for responding to climate change in the 1996 forest management plan for the Francis Marion. Based on assessment findings derived from TACCIMO, the FMNF planning team collaborated with Forest Service and partner scientists to integrate climate change considerations as they developed the ‘need to change’ document.
Sea level rise - The assessment identified current and projected sea level rise that is affecting the FMNF, yet the 1996 forest management plan does not mention this. The ‘need to change’ states that “Forest plan management direction is needed for ecological systems that are in the margin of change due to rising waters, as well as recreation developments and the risks associated with potential new development in the margin of change.” Management and/or monitoring actions to address this point will be included in the forest plan revision.
Longleaf pine restoration - The 1996 forest management plan does place importance on restoring longleaf pine ecosystems. However, in light of new estimates of their historical distribution and their expected resilience to climate changes and disturbances, the ‘need for change ‘ states: “Objectives need to be revised to increase the amount of maintenance or restoration of longleaf pine woodlands, flatwoods, and savannas for at least 50 percent or more of land with the ecological potential to support those ecosystems. Longleaf pine needs to be promoted over loblolly pine to increase sustainability of pine forests to severe wind and hurricane damage.”
Phase 2: Developing the forest plan Identifying Management Strategies The summary of Proposed Management Strategies builds on previous documents to outline some of the actions that may be included in a revised forest plan for the Francis Marion. Many proposed strategies in this document were not necessarily developed as direct responses to climate changes, but were reviewed by the planning team with climate change information in mind, and may have the indirect benefit of making forests more resilient to changes. However, TACCIMO did provide information to deliberately and directly include climate change response strategies in the document’s discussions on forest health and adaptive management, based on the integrated interpretation of resource area experts. This document is under discussion and open for public input.
Strategies proposed primarily to help maintain forest health on the FMNF under climate change include the following:
Reduce vulnerability by maintaining and restoring resilient native ecosystems, including streams and longleaf pine;
Enhance adaptation of species by reducing the effects of serious disturbances where possible and taking advantage of disruptions to convert to more resilient and desirable ecosystems;
Use preventive measures for reducing opportunities for forest pests;
Lessen greenhouse gas emissions by reducing carbon loss from hurricanes and restoring species such as longleaf pine that have higher carbon sequestration rates;
Maintain, improve and restore the diversity within stands to be ecologically sustainable;
Increase resilience of forests to both climate change and hurricane damage through landscape structural diversity;
Plant new trees and improve forest health through thinnings and prescribed burning to increase carbon for the future;
Address ecological systems that are in the margin of change due to rising waters, as well as, recreation developments and the risks associated with potential new development in the margin of change;
Address speedy salvage, road repairs or other ecological damages after major disturbances by tornados, hurricanes, wildfire, floods or drought;
Collaborate with partners and local municipalities to monitor the loss of marshlands, the effects of sea level rise on vegetation, saltwater intrusion, stream water temperatures and flows, and tidal forests and bald cypress for effects of increasing salinity.
Phase 3: Monitoring Integrating Multi-scale Monitoring in Plan Development The FMNF is developing a process for adaptive management and multi-scale monitoring that will play a key role in integrating climate change into the forest plan. Monitoring is essential for detecting changes in a timely manner and being able to respond to them effectively. For example, climate change leads to an increased risk of an invasive species being introduced on the forest. But forest managers have no way of knowing where or when exactly that introduction will happen. By setting up a monitoring strategy that accounts for anticipated climate impacts, the forest will be better able to adjust management approaches quickly to account for changes in the environment.
Currently, TACCIMO is supporting the process to develop a cohesive monitoring strategy along with plan revision team members, RO monitoring staff and South Atlantic Landscape Conservation Cooperative staff. They are collecting ideas on monitoring needs from sub-teams of people responsible for specific sections of the forest plan revision. All ideas are being compiled into a table that describes ecosystem drivers, stressors, indicators of those stressors, current monitoring efforts, and possible changes. Alerts are being developed for each monitoring indicator, that would incite further evaluation if conditions change. The alerts are paired with adaptive management strategies that will help the forest identify potential solutions when problems arise. Collectively, this information will represent the forest monitoring strategy, which closes the adaptive management cycle. For more information on these efforts, see Section 2.8 of the Proposed Management Strategies
Figure 2: The timeline for the Frances Marion National Forest Plan Revision.
Environmental Protection Agency, Oregon State University
The Environmental Protection Agency’s (EPA) Climate Economics Branch (CEB) analyzes cost-effective strategies to reduce greenhouse gas (GHG) emissions, both in the U.S. and internationally. EPA relies on the Forest and Agricultural Sector Optimization Model with Greenhouse Gas (FASOM-GHG) model for analysis of GHG mitigation from the U.S. forest, agriculture and bioenergy sectors. This project will involve model development, results interpretation, testing, analyses, and documentation associated with the forestry and bioenergy sectors and related land use in the FASOM-GHG. The overarching objectives of the project are to make the forest sector portion more flexible, able to simulate a broader range of alternative bioenergy and CO2 sequestration policies, and to simplify the basic model code to reduce compilation and run time.
The Environmental Protection Agency’s (EPA) Climate Economics Branch (CEB) analyzes cost-effective strategies to reduce greenhouse gas (GHG) emissions, both in the U.S. and internationally. EPA relies on the Forest and Agricultural Sector Optimization Model with Greenhouse Gas (FASOM-GHG) model for analysis of GHG mitigation from the U.S. forest, agriculture and bioenergy sectors. The model is developed and maintained by the FASOM-GHG team, with expert members at Texas A&M University, Oregon State University, the Nicholas Institute at Duke University, Research Triangle Institute, Electric Power Research Institute, Environmental Protection Agency, USDA and the U.S. Forest Service.
The CUFR Tree Carbon Calculator (CTCC) provides quantitative data on carbon dioxide sequestration and building heating/cooling energy effects provided by individual trees. CTCC outputs can be used to estimate GHG (greenhouse gas) benefits for existing trees or to forecast future benefits. The CTCC is programmed in an Excel spreadsheet and provides carbon-related information for trees located in one of sixteen United States climate zones.
This Carbon Calculator provides quantitative data on carbon dioxide sequestration and building heating/cooling energy effects provided by individual trees.
The National Climate Change Viewer allows users to visualize projected changes in climate (maximum and minimum air temperature and precipitation) and the water balance (snow water equivalent, runoff, soil water storage and evaporative deficit) for any state, county and USGS Hydrologic Units (HUC) in the continental United States. USGS HUCs are hierarchical units associated with watersheds and analogous to states and counties that span multistate areas. HUC levels 2, 4 and 8 are used in the viewer.
This viewer allows users to visualize past and projected changes in climate and the water balance for any state, county and USGS Hydrologic Unit.
The Water Erosion Prediction Project (WEPP), is a physically-based soil erosion prediction technology. WEPP has a number of customized interfaces developed for common applications such as roads, managed forests, forests following wildfire, and rangelands. It also has a large database of cropland soils and vegetation scenarios. The WEPP model is a distributed parameter, continuous simulation model, and is able to describe a given erosion concern in great detail for an experienced user.
The WEPP model consists of multiple applications that can estimate erosion and sediment processes on hillslopes and small watersheds, taking into account climate, land use, site disturbances, vegetation, and soil properties.
The Southern Regional Extension Forestry Office facilitates programming among professionals who work on many issues and opportunities facing the forestry and natural resources communities, including climate change.
PINEMAP integrates research, extension, and education to enable southern pine landowners to manage forests to increase carbon sequestration; increase efficiency of nitrogen and other fertilizer inputs; and adapt forest management approaches to increase forest resilience and sustainability under variable climates.
This peer-reviewed report is a thorough and comprehensive overview of how climate change is expected to affect the United States. It includes analyses of impacts on seven sectors – human health, water, energy, transportation, agriculture, forests, and ecosystems. The report also assesses U.S. regional impacts and outlines some climate adaptation efforts.