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2 28
<br />If you have spent any time sitting on the
<br />Riparia export animals to upland areas.
<br />Riverbank wondering how tihe whole thing
<br />Doyle (1990) suggested that riparia act as
<br />works, you have probably arrived at an intu -,...
<br />sources of mammalian species, while uplands
<br />itive feeling for the importance of riparia. In-.:
<br />act as dispersal sinks. Sinks are marginal
<br />this section, I briefly discuss seven scientific''
<br />areas to which surplus individuals disperse,
<br />reasons why riparia are crucial to the Ca-.-'
<br />and where survival and reproduction are
<br />capon's health. c :
<br />poorer than in high - quality habitats.
<br />First, the roots of riparian plants hold soil
<br />Fifth, riparia serve ,as corridors for disper-
<br />particles. Streamflow velocity increases on. thee,
<br />sal. As the forest of the Cacapon River basin
<br />outside of a bend, increasing the drag on the:
<br />more fragmented into isolated wood -
<br />streambank caused by passing water.(Kunzig _lots,
<br />riverside greenbelts will hold together
<br />1989). Thus, all streambanks erode, even in':077
<br />these biological islands, allowing movement
<br />pristine forests (Wehnes 1989). Man - caused,`'
<br />'of living things among patches and consequent
<br />accelerated streambank erosion, however,:,..
<br />outbreeding, and promoting the recolonization
<br />adds excessive silt, which degrades the River F,
<br />of patches that have lost their original natural
<br />(Turner and Speas 1988). :'..
<br />populations (Hunt 1988).
<br />Second, riparian trees contribute to the Ca- c,;. :..
<br />- ...Sixth, riparia contribute to the health of the
<br />capon's fishery. Trees shade the water, keep. :
<br />floodplain. An intact streamside plant com-
<br />ing it cool; they topple into the river, providing
<br />munity slows flood waters, allowing silt to
<br />cover; and they create overhangs, which are yet:;.
<br />, precipitate and enrich the floodplain (Naiman
<br />another kind of cover site (Hunt 1988)..
<br />et al. 1988). During extreme flood, streamside
<br />trees buffer bottomlands from scour and gravel
<br />Third, stream ecosystems receive much of
<br />deposits (Wehnes 1989).
<br />their energy from riparia. Leaves and twigs,,,
<br />from streamside plants fall into the River:.
<br />And seventh, and to me most important, ri-
<br />This organic debris is the food for many types" -.
<br />paria play crucial roles in maintaining .the
<br />of aquatic insects which -in turn - nourish -f`ish `
<br />Cacapon's high water quality. Riparia fulfill
<br />and birds. Bacteria and fungi break this plant
<br />this crucial function by, removing excess sed-
<br />material into even smaller particles (Kundt
<br />iment, nutrients, and other pollutants from
<br />1988). Because of the dependence of aquatic in -;''
<br />water running off the land (Naiman et al.
<br />sects on terrestrial plants, the insect species in :,
<br />1988). In one study, riparian galleries reduced
<br />the Cacapon may actually reflect the`;`.
<br />sediment entering a river by.94 %.
<br />characteristics of the riparian vegetation more
<br />than the River's mainstream _features...
<br />How do riparia neutralize the pollution
<br />(Petersen et al. 1987). ;. ,:�:.;,�
<br />carried by run -oO. Sediment particles precipi- .
<br />tate as the water is slowed by the greenbelt
<br />Fourth, riparia serve as wildlife refuges.
<br />(Hunt 1988). Nutrients, which would cause
<br />There are more individuals and a greater di-
<br />blooms of nuisance plants, are also removed.
<br />versity of species along the Cacapon than else-
<br />For example, phosphorus, carried by sediment
<br />where throughout our basin. One reason for
<br />in surface run -off (Peterson et al. 1987), is
<br />this is that riparia are ecotones, a type of ecolog-
<br />trapped by the forest. Nitrogen, on the other
<br />ical community bordering two different com-
<br />hand, which is primarily carried in the
<br />munities. Ecotones support more species than,
<br />groundwater, is retained within the riparium's
<br />either adjacent habitat because, in addition to
<br />soil, where it is denitrified and contributes to
<br />attracting species typical of each habitat, eco-
<br />the growth of riparian plants (Peterson et al.
<br />tones host organisms that require both. Farm-
<br />1987, Kundt 1988).
<br />stead shelterbelts, another type of ecotone, also
<br />show a high species diversity (Yahner 1983).
<br />Hill and Warwick (1987) provided a spe-
<br />�r,ar,gpl2ZI is published quarterly, with the arrival of each equinox and solstice, by Pine Cabin Run
<br />Ecological Laboratory, Route 1, Box 469, High View, WV 26808; (304) 856 -3911.
<br />Nancy Ailes, George Constantz, Jane Licata, James Matheson and Willard
<br />Wirtz; ,fit Dr. George Constantz, Laboratory Director; Nancy Ailes, Cacauon Editor; Zechnical
<br />Advisors: Dr. Joe Calabrese, Dr. Stephen Freiwell, Dr. Robert Kahn, Charles Licata, J.D., Dr.
<br />Michael Masnik, Dr. Chris Sacchi.
<br />
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