Abstract: Habitat is now the basis of most impact assessments and resource inventories, and it is the basis of many species management plans, mitigation planning, and environmental regulation. Habitats are relatively stable through time, easily defined in intuitive physical terms, and provide a tangible resource for negotiations and decision making. Numerous and varied methods of analyzing and reporting habitat conditions have been developed by federal, state, provincial, and private agencies. Habitat assessment approaches vary greatly among regions of the continent. The great variability in methods and an unusually wide range of practices have impeded the ability of agencies to share and synthesize information. A diversity of methods is desirable in the initial stages of a rapidly developing field, but enough time has passed to assess the state-of-knowledge and identify the best of the currently used methods and techniques. This manual is intended to provide fisheries biologists with a limited set of techniques for obtaining aquatic habitat data. The manual also describes the range of information collected and used in agency habitat analyses. Agencies planning habitat programs should review the synthesis of established and documented methods being used in North America (Appendix 1) and the planning recommendations in Chapter 2. Then, the remaining chapters should be reviewed to determine what types of habitat data should be included in the agency's program.

Increased water resources demand in rivers regulated by U.S. Army Corps of Engineers dams has intensified the conflict between preservation of lotic ecosystems and economic benefits of stream regulatin or channel modification. The Riverine Community Habitat and Restoration Concept (RCHARC) facilitates evaluation of effects of different channel configurations or release patterns on fish habitat and can be used to balance water resources development and natural resource preservation. The RCHARC is applied to the Gavins Point Dam tailwater of the Missouri River as a case history to assess the effects of different reservoir release alternatives on habitat for native riverine warmwater fishes. Application of the RCHARC requires four steps. First a comparison standard must be selected which the project alternatives can be contrasted. Second, hydrologic and hydraulic features of the comparison standard having fish habitat significance are described and summarized as an annual series of monthly depth or velocity frequency distributions. Third, a similar approach is used to describe hydrologic and hydraulic features of the project alternatives. Fourth, the habitat value of each of the project alternatives is determined by similarity of their depth or velocity distributions to the distributions of the standard. The more similar an alternative is to the standard system, the higher it will be ranked.

This open access book surveys the frontier of scientific river research and provides examples to guide management towards a sustainable future of riverine ecosystems. Principal structures and functions of the biogeosphere of rivers are explained; key threats are identified, and effective solutions for restoration and mitigation are provided. Rivers are among the most threatened ecosystems of the world. They increasingly suffer from pollution, water abstraction, river channelisation and damming. Fundamental knowledge of ecosystem structure and function is necessary to understand how human acitivities interfere with natural processes and which interventions are feasible to rectify this. Modern water legislation strives for sustainable water resource management and protection of important habitats and species. However, decision makers would benefit from more profound understanding of ecosystem degradation processes and of innovative methodologies and tools for efficient mitigation and restoration. The book provides best-practice examples of sustainable river management from on-site studies, European-wide analyses and case studies from other parts of the world. This book will be of interest to researchers in the field of aquatic ecology, river system functioning, conservation and restoration, to postgraduate students, to institutions involved in water management, and to water related industries.