Laserfiche WebLink
<br />communities along the Roanoke are thought to be distributed along a gradient of inundation <br /> <br />duration (or anoxic stress). With the elimination of high-magnitude flooding, higher <br /> <br />floodplain surfaces are now seldom if ever inundated, enabling less flood tolerant species to . <br /> <br />become established on lower sites, resulting in lowered overall vegetation diversity. This. <br /> <br />forest has been heralded as being the "highest quality and most extensive" bottomland ~u,n <br /> <br />hardwood forest on the southeastern Coastal. Plain (Lynch 1991). Changes in the forest could: <br /> <br />have serious implications,for.neotropical,migratoryrbirds using this area (Zeller 1993). <br /> <br />~~~~i: <br /> <br />,--'<", .- <br /> <br />", <br /> <br />:.~,. <br /> <br />-.,--' <br /> <br />Edwards Aquifer, Texas . <br /> <br />~~ <br />i~ ~.J-i' <br />'-, <br /> <br />been obtained by the USGS since 1932 in "Well J-17" near San Antonio, Texas. More- .. \ <br />';~k~;;t<:t;;:: <br />4000 water-supply wells have been drilled into the Edwards Aquifer since the early 1940's,..:~:::, <br />""'_:~>;1"-,'~;,r,'-~~;>>;_: <br />and'iiiecity of San Antonio depends entirely upon the aquifer for its water supplies. ~~"~.;'>' <br /> <br />the J-17 well is located near the aquifer's outflow point and is downgradient from most otller:F <br /> <br />wells, the hydrologic.:record,ac.the,J=l7-,welUntegrates the pumping effects of a great nuIilIlCr" <br /> <br />of upgradient wells. Since ground water pumping effects accumulate over time with <br /> <br />.,~~..,,"., <br /> <br />^ :j~s~t~{?~ ,.' <br />increasing numbers of wells, we have selected the first 20 years of aquifer monitoring r~ ' " <br /> <br /> <br />;'._;, <br /> <br />(1933-1952) uHepresent II pre-impact period. and the most recent20 years (1974-1993) fjd...._ <br /> <br /> <br />post-impact period. ' ";'-d;~I~~t, <br /> <br /> <br />Table 4 presents the IHA results for the Edwards Aquifer analysis, In reading the, ':'~." <br /> <br /> <br />table, it isimportant to bear in mind that larger water values indicate greater depths to ~'.' , <br /> <br />;,".',., .-- <br />_~ :i~f.<,,\'\.~-i~ '_',' _. <br />The relative difference between means ranged from -28% (Julian date of annuaP<"!~..,::~. . <br />. - ---:-'_-.-- ". ~,,~ <br /> <br />the well. <br /> <br />20 <br /> <br />