White, SM et al 2017 Legacies of stream channel modification revealed using General Land Office surveys, with implications for water temperature and aquatic life. Elem Sci Anth, 5: 3, DOI: https://doi.org/10. 1525/elementa.192 Introduction A major challenge of the Anthropocene-the period in which human activity is the dominant influence on climate and the environment-is to solve the interrelated problems leading to irreversible damage to planetary life support systems. These intertwined problems include human population growth, overconsumption, land use, climate change, and subsequent extinctions to biodiversity and elimination of ecosystem services (Foley et al., 2005; Barnosky et al., 2016). A common approach to forecasting the effects of human activity on the environment is through modeling scenarios of land use change and climate conditions, revealing various possible futures that can be embraced, avoided, or mitigated (Moss et al., 2010;Jantz et al., 2015;Isaak et al., 2016). In order to accomplish this, a comprehensive understanding of past human activities is needed, especially when past actions propagate a legacy extending to the present (Foster et al., 2003). The integrity of rivers and streams is especially vulnerable to human activities because hydrology and water temperature are strongly influenced by climatic effects (Dittmer, 2013) and the landscapes over which they flow (Hynes, 1975; Fausch et al., 2002; Allan, 2004). Streams and rivers provide important ecosystem services including clean and abundant water supply that are difficult to valuate but nonetheless essential (Arthington et al., 2010). Degradation of riverine ecosystems represents an important loss in terms of aquatic biodiversity (Dudgeon et al., 2006) and to people that depend upon rivers for food and other cultural values (Close et al., 2002).Modifications to river ecosystems in Europe, U.S., and other locations across the globe have been well documented. The European subcontinent has experienced land use change-specifically urbanization-since 700 B.C. (Antrop, 2004); these patterns have been manifested in several ways, but primarily as landscape fragmentation (Jaeger et al., 2011) and river channelization (Jurajda, 1995)
RESEARCH ARTICLELegacies of stream channel modification revealed using General Land Office surveys, with implications for water temperature and aquatic life Seth M. White * , Casey Justice * , Denise A. Kelsey * , Dale A. McCullough * and Tyanna Smith † Land use legacies can have a discernible influence in present-day watersheds and should be accounted for when designing conservation strategies for riverine aquatic life. We describe the environmental history of three watersheds within the Grande Ronde subbasin of the Columbia River using General Land Office survey field notes from the 19th century. In the two watersheds severely impacted by Euro-American land use, stream channel widths-a metric representing habitat simplification-increased from an average historical width of 16.8 m to an average present width ...