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<br /> <br />.i:~~..' <br />,"I' <br />.. <br />..':'~ <br />"',;; <br /> <br />the lll:ttM i.J. cU4pl4ced 41td 'O!l.C.ed to devdop 4 deepe;t., <br />naM.OWe.t clutnneL The teJlm ".'teVWftent" appUu to the. <br />vcvU.oUJ; typu 0' .s.ta.b.<U.za-tiDn 4t11uetu.-\u that Me eon- <br />.stJw.c.ted a..long Oil lleaJL the baIIIu 0' the /l.i.vtJt o.pp.\OWrtatdy <br />paIl.aU.el to the CUMen.t '.s . ,tow. RevWftenU Me al.60 COII- <br />.s.tltuc.ted 0& .stone Oil p.Uu 0It 4 comb.i.n4.ti.oll 0' .stolle 4IId <br />p.Uu. The deeput. '/l.4tut /l.i.vM 't0w6 Me UJ;u.4U.Ij on <br />the. outl..(de, 0It COlIC4ve, lo-ide 06 CUJlVU 0.\ be.nd4. ltlkU.e <br />d.i.ku Me lL6ed to IIOve 41td hotd the 'low aga..i.nt.t the. eon- <br />cave bank, ilevWftenU Me neeu.saJty to p1U1ttc.t thue banIu <br />'1lOlII eJlO.s.wn. RevWftenU Me geneMUy eon.t.Ulu0u.6 a..lons <br />the. e.nt.iJLe concave po,u,wn 0' ea.ch bend, t~ /l.4 <br />the. /l.i.vM beg.uu. to CUJlve.in 4 JtevM6e cUAeet.iDll. Reva- <br />men.t then .s.ta.U.6 011 the oppoUte bank /l.4 it beeomu the. <br />eollC4ve bank." (36) <br /> <br />The stabilization necessitates a continual replacement of <br />the revetments. Since slumping of the rock is a continual <br />process, it must be freshly applied at approximately three- <br />year intervals throughout the channelized portion of the <br />river. Figure 3 is provided to clarify this discussion. <br /> <br />5. Sediment Transport <br /> <br />~~'V~n~I~~~il~~iI~~{~~~~~e~~r:f~:~ ~~~ s <br /> <br />primary productivity of the river is a crucial factor in <br />comprehending the biotic characteristics. Tables 6 &.7 provide <br />annual sediment load and concentration averages. Table 8 <br />indicates the impact this has on light penetration. Light <br />penetration data from the unchannelized portion of the Mis- <br />souri River with lower suspended solids concentrations indi- <br />cate substantial light reduction at two feet below the <br />surface (43). Secchi disk measurements in the channelized <br />portion of the Missouri River with higher suspended solids <br />concentrations indicate substantial light reduction at less <br />than 12 to 14 inches below the surface (44. 45). <br /> <br />6. Sediment Deposition <br /> <br />As indicated previously, sediment depositing occurs whenever <br />velocity drops sufficiently to permit settling. This occurs <br />on a large scale behind the projecting dikes, but it occurs <br />continually throughout the river on a highly variable sched- <br />ule. For example, the moving sand dunes at the river bottom <br />are sites of deposition on their downstream slopes, crevices <br />in the rock revetment provide loca11zed slack water which <br />drops its sediment load until the crevice no longer exists <br />to prov1de the decreased flow circumstance. snagged debris <br />provides temporary sedimentation sites. With changes 1n flow <br />rate, slumping of rocks, dune movement, etc., the depos1ted <br />sediment is once again exposed to the flow that 1s sufficient . <br />to resuspend it J.9r further transport and ~ventual rede~ 10n. <br />'1lelc;Jftfft"9]:Oro1ie~~l:l1'"st'iiV~"bt fSu . . .rs-c <br />je(ffililr l~4$P9( tf~~eJ1"!\CI#!ferdiii . <br /> <br /> <br />31 <br /> <br /> <br /> <br />