The native diversity of vegetation types includes many types that are quite common and abundant across the landscape as well as those that are quite rare or considered at-risk of range-wide loss. The latter vegetation types may represent uncommon environmental conditions, such as serpentine or limestone outcroppings, where soil characteristics limit the pool of native plant species that could survive, and result in distinct plant assemblages.
In other instances, long histories of intensive land uses have resulted in the decline in extent and/or condition of the vegetation types to the point where there is significant conservation concern across their range of distribution. NatureServe and its network of state/tribal Network Programs conduct biodiversity field inventories and apply systematic criteria to determine the relative at-risk status of ecosystem and vegetation types. These criteria factor together trends in community extent, condition, and change agents to assign ranks from critically imperiled to relatively secure. In addition, the International Union for the Conservation of Nature (IUCN) has initiated efforts globally to “red list” ecosystem types for targeted conservation. Red listing identifies types that are considered “critically endangered,” “endangered,” or “vulnerable” throughout their range of distribution. Progress in this global effort includes vegetation types managed by the DoD in North America.
Planners should consult with NatureServe and Natural Heritage programs in their area to determine if there are at-risk ecosystems and vegetation types that they should be planning for their conservation.
In some cases, allowable actions may need to be more restrictive to protect sensitive ecosystem types occurring in easily disrupted environments. For example, this could be the case where surface soil disturbance could result in permanent damage or require decades for recovery. However, there are also many cases where active management—such as maintaining natural disturbance processes like wildfire—or some form of vegetation treatment are entirely appropriate to restore and maintain at-risk ecosystem types.
Landscape and ecosystem goals and objectives
Desired outcomes for landscape and ecosystems might be established at multiple scales. For example, this could include identifying areas of ecological importance that, at a regional scale, represent characteristic and at-risk ecosystem types and provide habitat for special-status species. They may also identify regional to local land use restrictions and/or treatment zones to achieve desired vegetative states and conditions. Often, implementation decisions identify the site-specific management practices, such as vegetation treatments to achieve desired vegetation structure and composition.
First, assessment could address a range of management questions regarding ecosystem types, including where is each type? Are there types considered to be endangered or vulnerable? What proportion of the type occurs on DoD lands vs. other agencies vs. private lands? How much of each type occurs within different levels of protective management, such as in parks and wilderness areas? What is the current ecological condition of the type occurring on the installation? Is there a need for actions for restoration or maintenance?
The results of these assessments could identify needs for changing current resource management on the installation. They could suggest goal statements, such as securing high-condition examples and/or some proportion of the distribution of each vegetation type within protected or compatible managed lands on or adjacent to the DoD installation. These areas could provide habitat to head off listing of species that could become listed under the Endangered Species Act. They could also serve as “reference locations” for each major vegetation type to provide context and perspective for vegetation management throughout the region over time.
Related objectives could then specify locations and/or specific areal extents by ecosystem type that should be secured in this form within some time period, such as a stated percentage secured by ecoregion, major watershed, or other geographic unit. Both desired outcomes (representing diversity) and allowable uses (under some form of compatible management regime) are captured in this type of goal and objective statement.
Next Page: Resources
Author
Patrick Comer, Ph.D., Chief Ecologist
NatureServe
Managing Landscapes and Ecosystems
Managing Landscapes and Ecosystems
Box 8.2: Conserving rare and special status vegetation types