59
© The Author(s) 2018
E. Wohl, Sustaining River Ecosystems and Water Resources, SpringerBriefs in
Environmental Science, DOI 10.1007/978-3-319-65124-8_3
Chapter 3
Human Alterations of Rivers
People have been altering the environment since prehistory. Archeological records
and the stratigraphy of valley bottoms suggest that prehistoric alteration of native
upland vegetation for grazing and crops resulted in enhanced sediment yields to
river corridors, as well as associated changes in channel dimensions and planform
and channel-floodplain connectivity (e.g., Mei-e and Xianmo 1994; Stinchcomb
et al. 2011). The magnitude of these changes varied through time and space.
Examples of intensive vegetation clearing and valley-bottom aggradation come
from diverse regions. In the southeastern United States, nineteenth century rowcrop agriculture led to floodplain deposition of more than a meter of sediment
(Jackson et al. 2005). In southeastern Australia, nineteenth century land clearance
caused channel and floodplain aggradation (Brooks and Brierley 1997). In southern
Poland, land clearance for agriculture during the late seventeenth to nineteenth centuries triggered increased sediment yields that changed meandering rivers into
braided channels (Latocha and Migoń 2006). Conversely, twentieth century declining resource use, regrowth of upland vegetation, and erosion of channels occurred
in mountainous regions of western and central Europe (Latocha and Migoń 2006).
Understanding the history and characteristics of environmental alteration are
important for effective river management because even activities undertaken more
than a century ago and physically outside of the river corridor can continue to influence river form and process in ways that are not always readily apparent. This chapter reviews the plethora of human activities that have directly and indirectly affected
river ecosystems.
In the context of river networks and river corridors, human environmental alteration can be distinguished as indirect or direct. Indirect alterations are those within
the drainage basin but outside of the river corridor. Changes in land cover or climate, for example, can alter water and sediment yields to river corridors, as well as
nutrient inputs and riverine biota. Direct alterations are those within the river network. Direct alterations affect river corridor configuration and connectivity, as well
as water and sediment regimes. Explicitly distinguishing these categories of altera-
© The Author(s) 2018
E. Wohl, Sustaining River Ecosystems and Water Resources, SpringerBriefs in
Environmental Science, DOI 10.1007/978-3-319-65124-8_3
Chapter 3
Human Alterations of Rivers
People have been altering the environment since prehistory. Archeological records
and the stratigraphy of valley bottoms suggest that prehistoric alteration of native
upland vegetation for grazing and crops resulted in enhanced sediment yields to
river corridors, as well as associated changes in channel dimensions and planform
and channel-floodplain connectivity (e.g., Mei-e and Xianmo 1994; Stinchcomb
et al. 2011). The magnitude of these changes varied through time and space.
Examples of intensive vegetation clearing and valley-bottom aggradation come
from diverse regions. In the southeastern United States, nineteenth century rowcrop agriculture led to floodplain deposition of more than a meter of sediment
(Jackson et al. 2005). In southeastern Australia, nineteenth century land clearance
caused channel and floodplain aggradation (Brooks and Brierley 1997). In southern
Poland, land clearance for agriculture during the late seventeenth to nineteenth centuries triggered increased sediment yields that changed meandering rivers into
braided channels (Latocha and Migoń 2006). Conversely, twentieth century declining resource use, regrowth of upland vegetation, and erosion of channels occurred
in mountainous regions of western and central Europe (Latocha and Migoń 2006).
Understanding the history and characteristics of environmental alteration are
important for effective river management because even activities undertaken more
than a century ago and physically outside of the river corridor can continue to influence river form and process in ways that are not always readily apparent. This chapter reviews the plethora of human activities that have directly and indirectly affected
river ecosystems.
In the context of river networks and river corridors, human environmental alteration can be distinguished as indirect or direct. Indirect alterations are those within
the drainage basin but outside of the river corridor. Changes in land cover or climate, for example, can alter water and sediment yields to river corridors, as well as
nutrient inputs and riverine biota. Direct alterations are those within the river network. Direct alterations affect river corridor configuration and connectivity, as well
as water and sediment regimes. Explicitly distinguishing these categories of altera-