Great Basin riparian ecosystems: ecology, management and restoration.

Applied ecosystem scientists tend to share several articles of faith: (1) that a clearer understanding of spatial and temporal patterns will better inform management decisions; (2) that patterns and relationships need to be examined at multiple scales; and (3) that effective study of ecosystems is fundamentally interdisciplinary. Occasionally a project such as the one described in this book affirms those principles. Chambers and Miller’s edited compilation of chapters by a total of 18 investigators summarizes a decade of work by the U.S. Forest Service’s Great Basin Ecosystem Management Project on Restoring and Maintaining Sustainable Riparian Ecosystems. The book is published as part of the Society for Ecological Restoration’s series on The Science and Practice of Ecological Restoration. At the most general level, this book provides a good model of interdisciplinary ecosystem science by describing the research of federal agency scientists and university researchers. The book demonstrates research collaborations between a diverse set of disciplines including plant and animal ecology, fluvial geomorphology, soil science, paleoecology, geology, and hydrology and strikes a good balance between individually credible studies and the synergistic combination of disciplines. Ecosystem restoration, and riverine restoration in particular, is currently grappling with the articulation of general principles and the use of case studies to identify effective procedures and ‘‘lessons learned.’’ This regional analysis of trajectories of ecosystem change, controlling variables, and impact sensitivities offers a real alternative for how ecosystem science might inform restoration actions. Great Basin Riparian Ecosystems focuses on perennial, high-gradient, upland streams in narrow valleys of the Shoshone, Toiyabe, Toquima, and Monitor Mountain Ranges in central Nevada. There are strong elevational gradients in vegetation and precipitation, with riparian zones consistently representing the wet places in a dry landscape. These watersheds are of particular interest to the U.S. Forest Service. However, the book does not encompass lowland and ephemeral streams of the Great Basin and the associated impacts of flow depletion. The topics in the well cross-referenced chapters include paleoecological reconstruction of Holocene climate and vegetation changes (Tausch, Nowak, and Mensing); reconstruction of late Holocene fluvial dynamics (Miller, House, Germanoski, Taush, and Chambers); basin sensitivity to channel incision (Germanoski and Miller); surface water–groundwater interactions at riparian meadow sites (Jewett, Lord, Miller, and Chambers); relations of vegetation pattern to hydrology (Chambers, Tausch, Korfmacher, Germanoski, Miller, and Jewett); water quality characteristics (Amacher, Kotuby-Amacher, and Grossl); patterns of native species richness (Flieshman, Dunham, Murphy, and Brussard); and a synthesis discussion emphasizing implications for management and restoration (Chambers, Miller, Germanoski, and Weixelman). Much of the book concentrates on vegetation as it is influenced by hydrology and the physical variables that determine hydrologic gradients. The chapter on water quality concludes that catchment lithology is the dominant influence on chemical composition, with overall high water quality in mountain streams, and little indication of water quality pattern in these streams due to human activities. Animal distributions, habitat usage, and population dynamics are not strongly considered. The chapter on species richness does provide a thoughtful discussion of alternative general approaches (historical changes, predictive models, surrogate species, and island biogeography) illustrated with data on butterfly distributions. Little attention is given to the currently challenging issues in western riparian management concerning protection and restoration for wide-ranging species, such as neotropical migratory birds and sage grouse, which depend on riparian areas as part of their usage of large landscapes. The most compelling theme of the book is the hydrologic determination of vegetation pattern and dynamics as it is traced back through interactions of surface and subsurface hydrology in a fluvial geomorphic surface responding to local and immediate perturbations, but conditioned by geologic history and long-term climatic variation. For example, riparian wet meadows are the focal point of human impact and restoration actions in these riverine systems. The mesic vegetation of these meadows is linked to high groundwater levels, which often occur upstream of side-valley alluvial fans. Channel incision through these meadow systems produces lowered groundwater levels and shifts in the vegetation toward more xeric species.