No abstract

Statistical descriptions of reconstructed fire regimes are often extrapolated from a composite of small forest stands to represent extensive geographical areas. However, statistical properties of fire regimes are scale‐dependent, thus causing some extrapolations from fine scale to coarse scale and comparisons between fire‐scar‐based reconstructions to be inappropriate. We assessed landscape fire regimes of the Sacramento Mountains, in southern New Mexico, using dendrochronological methods and a variety of fire statistics and analysis filters. We reconstructed historical and recent fire regimes for the Mescalero Apache Tribal Lands (MATL) at tree and site scale (25 ha). We then estimated the Sacramento Mountains historical and recent fire regimes by combining paleo fire data from this study with published data from the adjacent Lincoln National Forest (LNF). We applied filters to provide fire statistics that are relatively unbiased to the different spatial measurement extent of the studies. This is the first study to assess fire regime in the MATL over multiple spatial and temporal scales. The results show that frequent surface fires occurred at all scales in the Sacramento Mountains until fire was excluded from the landscape in the early 1900s. Historical fires were found to be synchronous with drought years, typically La Niña events, and often preceded by wet years. We did not find evidence supporting differences in fire regimes between the MATL and the LNF, suggesting that fire cessation following intensive Euro‐American settlement was widespread. The interruption of frequent surface fires, together with other changes in forest structure and climate, pose a significant threat to sustainability of forest ecosystems on Native American tribal lands.

The Mescalero Apache Tribal Lands (MATL) provide a diverse range of ecosystem services, many of which are of fundamental importance for the Mescalero Apache Tribe’s well-being. Managing forests on MATL, especially under climate change, involves prioritizing certain ecosystem services. We used an iterative survey of experts’ opinions to identify those ecosystem services that 1) have high utility—services that the Tribe uses, or could use, and are obtained directly or indirectly from the MATL; 2) are irreplaceable—services that cannot be provided by any other natural resource; and 3) are under a high level of threat—services at risk of declining or being lost directly or indirectly by climate change and thus are critical for management. Both scientists and practitioners identified water and cultural services as management priorities. Management recommendations to mitigate and adapt to climate change effects include reintroduction of fire in the landscape, assisted migration, creation of age/size mosaics across the landscape, and incorporation of green energy. Incorporating human perspectives into natural resource management is a critical component to maintain and adapt social–ecological systems to climate change, especially for Indigenous communities with inherent rights of sovereignty who are deeply connected to natural resources. This study demonstrates how knowledge systems are complementary: diverse perspectives related to values and threats of ecosystems can be incorporated to coconstruct ecosystem management decisions.

Forests are critically important for the provision of ecosystem services. The Sacramento Mountains of New Mexico, USA, are a hotspot for conservation management and the Mescalero Apache Tribe's homeland. The multiple ecosystem services and functions and its high vulnerability to changes in climate conditions make their forests of ecological, cultural, and social importance. We used data from the Mescalero Apache Tribal Lands (MATL) Continuous Forest Inventory over 30 yr to analyze changes in the structure and composition of ecosystems as well as trends in ecosystem services. Many provisioning, regulating, cultural, and supporting services were shared among the MATL ecosystems and were tied to foundational species dominance, which could serve as a reliable indicator of ecosystem functioning. Our analysis indicates that the MATL are in an ongoing transition from conifer forests to woodlands with declines in two foundation species, quaking aspen and ponderosa pine, linked to past forest management and changing climate. In addition, we detected a decrease in species richness and tree size variability, amplifying the risk of forest loss in a rapid climatic change. Continuous permanent plots located on a dense grid (1 × 1 km) such as the ones monitored by the Bureau of Indian Affairs are the most detailed data available to estimate forests multiresource transitions over time. Native lands across the USA could serve as the leading edge of detecting decadal‐scale forest changes and tracking climate impacts.