Mark E. Jensen

Knowledge-based assessment of watershed condition

The USDA Forest Service and Environmental Protection Agency have cooperatively developed a knowledge base for assessment and monitoring of ecological states and processes in sixth-code watersheds. The knowledge base provides a formal logical specification for evaluating watershed processes, patterns, general effects of human influence, and specific effects on salmon habitat. The knowledge base was designed in the NetWeaver knowledge base development system and evaluated in the Ecosystem Management Decision Support (EMDS) system. EMDS is an application framework for knowledge-based decision support of ecological landscape analysis at any geographic scale. The system integrates geographic information system and knowledge base system technologies to provide an analytical tool for environmental assessment and monitoring. The basic objective of EMDS is to improve the quality and completeness of environmental assessments and the efficiency with which they are performed. This paper presents an overview of the NetWeaver and EMDS systems, describes the general structure of the knowledge base for watershed assessment, and presents a small example of its use for evaluating erosion processes.

An Automated Technique for Delineating and Characterizing Valley-Bottom Settings

Accurate delineation and characterization of valley-bottom settings is crucial to the assessment of the biological and geomorphological components of riverine systems; yet, to date, most valley-bottom mapping endeavors have been done manually. To improve this situation, we developed automated techniques in a Geographic Information System (GIS) for delineating and characterizing valley-bottom settings in river basins ranging in size from approximately 1,000–10,000 km2. All procedures were developed with ARC/INFO GIS software and fully automated in Arc Macro Language (AML). The GRID module is required for valley-bottom delineation and slope calculations; whereas characterization (i.e., measuring the width of the valley-bottom zone) requires Coordinate Geometry (COGO) in the ARCEDIT module. The process requires three inputs: a polygon coverage of the analysis area; an arc coverage of its hydrography, and a grid representing its digital elevation. The AML is designed to operate within a wide range of computer memory/disk space options, and it allows users to customize several procedures to match the scale and complexity of a given analysis area with available computer hardware.

Mapping Patterns of Human Use and Potential Resource Conflicts on Public Lands

Focusing on a 2.2 million hectare area surrounding the Lolo National Forest in western Montana, USA, we illustrate a GIS method for predicting patterns of human use on public lands and highlighting potential for impacts on fish and wildlife species. Data inputs include human population count (derived from the 1990 Census), roads and trails, and the predicted distributions of bull trout (Salvelinus confluentus) and 41 terrestrial vertebrates of special concern. Because results highlight areas where conflicts between humans and resources may occur, they are of potential use to land managers. This approach can be applied wherever data are available, and inputs can be varied according to the topics of interest.

Ecosystem Characterization and Ecological Assessments

Ecological assessments are an important component of any strategy for making or reevaluating land management and regulatory decisions (see Chapters 1, 9, and 35; also Slocombe, 1993; Jensen and Bourgeron, 1994; Bourgeron et al., 1995). An important objective of ecological assessments is the identification, location, and description of the biotic and abiotic features of a landscape. Landscape features exhibit heterogeneity at a variety of scales (Turner et al., 1995). This heterogeneity is characterized by identifying relevant patterns and the processes that produce patterns in a landscape (Bourgeron and Jensen, 1994). Distinct patterns and processes occur at a variety of spatial and temporal scales of organization (see Chapter 2). For ecological assessments, an explicit understanding is needed of the scaled relationships of biological and biophysical characteristics from site to regional scales (Lessard, 1995; Lessard et al., 1999). Therefore, the characterization process is a multiscaled approach conducted within a hierarchical framework (Bourgeron and Jensen, 1994; Hann et al., 1994; Bourgeron et al., 1995; Jensen et al., 1996).

Application of Ecological Classification and Predictive Vegetation Modeling to Broad-Level Assessments of Ecosystem Health

The Little Missouri National Grasslands (LMNG) of western North Dakota support the largest permitted cattle grazing use within all lands administered by the USDA, Forest Service, as well as critical habitat for many wildlife species. This fact, coupled with the need to revise current planning direction for range allotments of the LMNG, necessitated that a broad-level characterization of ecosystem integrity and resource conditions be conducted across all lands within the study area (approximately 800,000 hectares) in a rapid and cost-effective manner. The approach taken in this study was based on ecological classifications, which effectively utilized existing field plot data collected for a variety of previous inventory objectives, and their continuous spatial projection across the LMNG by maps of both existing and potential vegetation. These two map themes represent current and reference conditions (existing vs. potential vegetation); their intersection allowed us to assign various ecological status ratings (i.e., ecosystem integrity and resource condition) based on the degree of departure between current and reference conditions. In this paper, we present a brief review of methodologies used in the development of ecological classifications, and also illustrate their application to assessments of rangeland health through selected maps of ecological status ratings for the LMNG.

An Overview of Ecological Assessment Principles and Applications

Ecological assessments facilitate understanding of an area’s past, present, and future conditions through comprehensive description of ecosystem patterns, processes, and functions (Lessard et al., 1999). They synthesize our knowledge of ecological Systems and commonly describe the biophysical and social limits of a system, the interrelations of its ecosystem components, and the uncertainties and assumptions that underlie a given assessment effort. Ecological assessments are not decision documents because they do not resolve issues or provide direct solutions to specific policy questions. Instead, they provide the foundation for proposed additions or changes to existing land management plans or regulatory policies and are a critical component for implementing principles of ecosystem management in land management planning (Grossarth and Nygren, 1994; Morrison, 1994; Haynes et al., 1996).

Assessment of Biotic Patterns in Freshwater Ecosystems

Whether curse or blessing, scientists and managers have developed a multitude of approaches to the assessment of patterns in the biota of freshwater ecosystems. Several rather independent traditions in aquatic ecology have focused on the relationship of ecological pattern to physical pattern and process. Approaches that focus on broad-scale, regional patterns may completely miss aspects of the ecosystem that are critical to the survival of rare taxa in special habitats, just as approaches that focus on rare species or endangered populations may provide little information about the broader biotic community and its response to an ecological change (Table 26.1). Today’s natural resource laws, societal expectations, limited fiscal resources, and declining biotic resources demand that these once separate strands converge in a more holistic approach to ecological assessment. This brief review cannot aspire to map a clear path toward meeting that major challenge, but is intended only to till the ground for future synthesis.

General Data Collection and Sampling Design Considerations for Integrated Regional Ecological Assessments

Large-scale data collection is the initial observational phase of integrated regional ecological assessments (IREAs). The data collection methodology determines to a large extent the accuracy and precision of all subsequent analyses, such as pattern recognition (Bourgeron and Jensen, 1994; Bourgeron et al., 1994a; Dale and O’Neill, 1999). The data analysis and interpretative phases of IREAs often tend to be emphasized by scientists over formal data collection procedures (see the case studies in Chapters 30 through 34; for a very formal approach to survey design, see the US-EPA Ecological Monitoring and Assessment Program, O’Neill et al., 1994; Kapner et al., 1995). The lack of formal, consistent data collection protocols for IREAs is unfortunate, because the quality of the characterization of a region and the quality of subsequent interpretations depend on the quality of the data, both in terms of the thoroughness of coverage and the type of information collected.

Elements of Ecological Land Classifications for Ecological Assessments

An ecological land classification (ELC) is the product of the formal definition of land-based ecosystems and ecosystem complexes (Rowe and Sheard, 1981; Sims et al., 1996), based on the ecological and mapping principles of ecosystem characterization (see Chapters 2 and 3). In addition to the specific requirements of ecosystem characterization (see Chapter 3), constructing an ELC requires making decisions about the classification concepts to follow and the specific uses of the ELC (Grossman et al., 1999). In practice, the classification process is a balance between science and art (Sims et al., 1996).

Integrated Ecological Assessments and Land-Use Planning

A requirement for ecological information to identify, quantify, and evaluate the potential impact of land-use decisions on ecosystems has been recognized for some time (Everett et al. 1994; O’Callaghan 1996;Boyce and Haney 1997; Lyle 1999; Treweek 1999; Jensen et al. 2001). The process of integrated ecological assessment (IEA) has been developed to provide a comprehensive description of the ecosystem patterns, processes, and functions, including relevant socio-political factors, needed to synthesize our knowledge of ecological and human systems. IEA techniques are rooted in ecological, social, and economic sciences. IEAs incorporate evaluation of the implications of human activities, including production of land-management scenarios. They should be part of integrated systems of environmental regulation that include strategic planning, objective setting, performance standards, monitoring, and review of the entire process (Treweek 1999). Recent applications of IEAs (see case studies in [1998] and [2001]) represent the integration of a number of approaches developed in response to specific problems, socio-political contexts, national legislation, and international accords (see review in [1999]; see also [1999]; and [1999]). Various terms have been used to describe all or part of the process of assessing the state of the environment and its relationship to economic development.