Although the Northwest currently has the least proportion of non-native invasive plant species relative to other regions of North America, invasions continue to increase into the mountainous areas of the region. Landscape structure, such as the variation found along the complex gradients of the Northwest mountain ecoregions, affects the expansion of invasive plant species and the invasibility of plant communities. Also, the history of land use and current use patterns affect the expansion of invasive plants, and many of the deteriorated environments in the region's mountains may invite and stabilize plant invasions. We examined the patterns of invasive plant diversity in Northwest mountain ecoregions, as derived from literature sources, to analyze which factors influence plant invasions. Our analysis found altered riparian systems and disturbed forests to be especially vulnerable to plant invasion. Conversely, alpine and wilderness areas are still relatively unaffected by invasive plants. Both riparian and alpine communities, while making up a relatively small area across Northwest mountain ecoregions, have significant ecological importance and deserve special protection from invasive plant introductions. Human settlement at low elevations and intense land use of upland forests will likely continue to enhance invasive plant introductions into Northwest mountain ecosystems. Knowledge of the relationships between biological and environmental factors, disturbance, and human land use will be critical for future management strategies that proactively locate, prevent, or contain plant invasions in the mountains of the Northwest.

https://www.fs.fed.us/pnw/pubs/journals/pnw_2005_parks002.pdf

Natural and land-use history of the Northwest mountain ecoregions (USA) in relation to patterns of plant invasions

North American tree species, subspecies and genetic varieties have primarily evolved in a landscape of extensive continental ice and restricted temperate climate environments. Here, we reconstruct the refugial history of western North American trees since the last glacial maximum using species distribution models, validated against 3571 palaeoecological records. We investigate how modern subspecies structure and genetic diversity corresponds to modelled glacial refugia, based on a meta-analysis of allelic richness and expected heterozygosity for 473 populations of 22 tree species. We find that species with strong genetic differentiation into subspecies had widespread and large glacial refugia, whereas species with restricted refugia show no differentiation among populations and little genetic diversity, despite being common over a wide range of environments today. In addition, a strong relationship between allelic richness and the size of modelled glacial refugia (r(2) = 0.55) suggest that population bottlenecks during glacial periods had a pronounced effect on the presence of rare alleles.

/pdf/glacial-refugia-and-modern-genetic-diversity-of-22-western-5960fmb37x.pdf

Glacial refugia and modern genetic diversity of 22 western North American tree species

Summary This paper presents a new approach to the conceptualization and assessment of well-being in forest-dependent communities. Studies of well-being in agrarian communities, boomtowns (communities undergoing rapid growth), and forest-dependent communities are examined to highlight common themes in natural resource-dependent community studies. Social indicators are discussed and a summary of weaknesses presented. The county, a commonly used unit of analysis, is rejected in favor of a more socially relevant unit. This new approach to well-being in forest communities begins with definitions of the terms community and forest dependence. The work of Amartya Sen, whose conceptualization of well-being focuses on the real opportunities people have and their achievements in light of their opportunities, forms the foundation of the new approach proposed here. Sen's conceptualization is broadened by focusing on the community and acknowledging the importance of a sense of place. Methodologically, this new approach...

Assessing Well-Being in Forest Dependent Communities

A framework for ecosystem management is proposed. This framework assumes the purpose of ecosystem management is to maintain the integrity of ecosystems over time and space. It is based on four ecosystem principles: ecosystems are dynamic, can be viewed as hierarchies with temporal and spatial dimensions, have limits, and are relatively unpredictable. This approach recognizes that people are part of ecosystems and that stewardship must be able to resolve tough challenges including how to meet multiple demands with finite resources. The framework describes a general planning model for ecosystem management that has four iterative steps: monitoring, assessment , decision-making, and implementation. Since ecosystems cross jurisdictional lines, the implementation of the framework depends on partnerships among land managers, the scientific community, and stakeholders. It proposes that decision-making be based on information provided by the best available science and the most appropriate technologies for land management. The Interior Columbia Basin Ecosystem Management Project received extensive comments (including anonymous peer reviews) on previous versions of the " Framework for Ecosystem Management in the Interior Columbia Basin. " Lack of clarity was the main complaint. Earlier versions were too vague, conceptual, technical, and contained too much jargon. At the same time, many people requested more detail, and mechanisms for implementing ecosystem management. People wanted to know how to link science and land management planning, how this process would be translated into action, how ecosystem management could be incorporated into existing planning processes and decisions, and how a more effective means of stakeholder participation could be developed. In response to these comments, we prepared a new introduction defining the objectives of ecosystem management and the framework. We expanded the discussion of the science concepts underlying ecosystem management. We expanded the discussion of the general planning model and included a discussion of risk assessments. We expanded the discussion on planning and decision-making to explain the connection between assessments and land-use planning processes. The section also attempts to define broader and more effective mechanisms for stakeholder participation.

/pdf/a-framework-for-ecosystem-management-in-the-interior-2c22p3sk4p.pdf

A framework for ecosystem management in the Interior Columbia Basin including portions of the Klamath and Great Basins.

https://www.fs.fed.us/rm/pubs_other/rmrs_2012_marcot_b001.pdf

Recent advances in applying decision science to managing national forests

Interior Columbia Basin ecosystem management project

/pdf/interior-columbia-basin-ecosystem-management-project-2kz2o36zlm.pdf

J. Stephen. Shelly

Papers

Interior Columbia Basin ecosystem management project

Interior Columbia Basin ecosystem management project : analysis of vascular plants /