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<br />
<br />River-Floodplain Environments
<br />
<br />Because of strong economic, political, and social pressures from humans
<br />for multiple use of large river-floodplain systems for hydroelectric power,
<br />agriculture, industry, and municipal uses, it is doubtful that restoration of
<br />rivers (Le., return to a truly original state) (Bradshaw, 1996) is possible.
<br />However, it is possible to mitigate (Le., to moderate), to remediate (Le., to
<br />rectify), or to enhance (Le., to improve) environmental conditions in a river
<br />ecosystem (Stanford et aI., 1996). Any habitat enhancement of structure
<br />and function of river-floodplain ecosystems will allow improvement of
<br />environmental integrity (Stanford et aI., 1996; Poff et aI., 1997).
<br />Although regulated rivers may be hydraulically optimum for human
<br />needs, they are poor ecological systems compared with unaltered rivers.
<br />Attempts to enhance or restore ecologically degraded river ecosystems
<br />are expensive and often cannot entirely restore all natural ecological
<br />conditions (Petts, 1994). Human cultural characteristics, values, percep-
<br />tions, attitudes, and responses to flooding vary considerably in different
<br />parts of the world (White, 1974; Laituri, Chapter 17, this volume) and
<br />exclusion of sustainable use of water resources by humans will prob-
<br />ably result in failure to maintain or enhance the ecological integrity of
<br />aquatic systems (Cairns, 1995). Gore and Shields (1995) provided an ex-
<br />ample of constructing setback levees along the Danube River in the Czech
<br />Republic that provided human safety while recovering some ecologi-
<br />cal function and value of floodplain habitat. In another example, Heiler
<br />et aI. (1995) describe how hydrological connectivity and flood pulses will
<br />be restored in a free-flowing reach of the Danube River, downstream of
<br />Vienna, Austria, as the basis for ecosystem management for a natipnal
<br />park.
<br />Power et aI. (1995a) pointed out that flooding in the Mississippi River
<br />. during 1993 "rekindled the national debate [in the United States] over what
<br />is to be gained by increasing the height and extent of levees and what has
<br />been lost." Aquatic ecosystem management should focus on guiding nat-
<br />ural processes of streamflow, erosion, sedimentation, and seasonal flood
<br />pulses when making decisions related to river management (Sparks, 1995;
<br />Poff et al., 1997). Sparks (1995) stated that "Ecosystem management could
<br />actually save money and increase economic efficiency in the long run, be-
<br />cause natural functions are restored (e.g., flood storage, conveyance, and
<br />moderation; water purification; production of fish and wildlife; and preser-
<br />vation of biodiversity) instead of being maintained by human intervention
<br />at great cost and considerable risk of failure." Re-regulation of streamflows
<br />and reconnection of floodplains, at least periodically, could reestablish
<br />some ecological integrity of river-floodplain ecosystems without signifi-
<br />cantly compromising human uses (Stanford et aI., 1996).
<br />Management decisions related to river-floodplain management must
<br />be made with full consideration of the ecological, economical, political,
<br />and sociological factors (Table 9.8) to reduce conflicts' and avoid polariza-
<br />tion of issues regarding human use of water resources and preservation
<br />of aquatic systems (Brown, 1992). Effective management of multiple-use
<br />rivers through more effective communication among the public, planners,
<br />politicians, engineers, and ecologists can benefit people as well as the
<br />ecological function and integrity of aquatic systems (Brown, 1992; Hey,
<br />1994). Although uncertainty exists with every management decision be-
<br />cause all information required for optimal management decisions usually
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