John S. Richardson
Mark S. Wipfli
2015
<p>Riparian areas are the terrestrial environment adjacent to water that both influences and is influenced by the aquatic feature (Gregory <i>et al</i>., 1991; Naiman <i>et al</i>., 2010). Riparian areas along streams provide shade, sources of wood and organic matter, contribute to bank stability, filter sediments, take up excess nutrients from groundwater inputs, and other key processes that protect freshwaters (e.g. Naiman <i>et al</i>., 2010; Richardson & Danehy, 2007; Figure 9.1). Riparian areas also increase biodiversity through habitat complexity and close juxtaposition of aquatic and terrestrial environments (Quinn <i>et al</i>., 2004; Naiman <i>et al</i>., 2010). Alterations to riparian areas, despite their small area relative to the landscape, have disproportionate effects on habitats and fish communities (Naiman <i>et al</i>., 2010; Wipfli & Baxter, 2010). Key habitat losses and alterations are derived from modification of riparian areas by reducing instream habitat complexity (Bilby & Ward, 1989; Fausch & Northcote, 1992; Naiman <i>et al</i>., 2010), diminishing the productive basis of freshwater food webs (Belsky <i>et al</i>., 1999; Quinn <i>et al</i>., 2004), increasing nutrient, contaminant and sediment intrusion (Muscutt <i>et al</i>., 1993; Daniels & Gilliam, 1996; Nguyen <i>et al</i>., 1998; Waters, 1999).</p>
<p>Riparian and freshwater ecosystems are typically tightly coupled, especially in their natural states, and the linkages that couple them frequently exert strong influence on their associated invertebrate and fish fauna (e.g. Gregory <i>et al</i>., 1991; Naiman <i>et al</i>., 2010). Riparian habitats, and the condition of these habitats, further plays a key role in the ecology of these fresh waters, influencing critical processes such as water, nutrient and sediment delivery and dynamics; prey resources for fish and other consumers, and other organic materials exchanged between aquatic and terrestrial habitats (Nakano <i>et al</i>., 1999; Naiman <i>et al</i>., 2010); light and water temperature dynamics that in turn affect food web processes and fish metabolism and growth; aquatic physical habitat (wood); and terrestrial consumers that prey upon fishes (Bisson & Bilby, 1998; Naiman <i>et al</i>., 2010; Wipfli & Baxter, 2010). These processes in turn directly or indirectly influence fishes in freshwater systems (Wang <i>et al</i>., 2001; Pusey & Arthington, 2003; Allan, 2004; Richardson <i>et al</i>., 2010a).</p>
application/pdf
10.1017/CBO9781139627085.010
en
Cambridge University Press
Management and the conservation of freshwater ecosystems
chapter