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<br />71
<br />
<br />hl>ls I. c.u,"f1.. of O'.e..i~ "-unet. Ifl LotlC 1~"'f'l_ ("""Ifi.. Ir_ C_.". .... 1.1.... ,,,,).
<br />
<br />lloodr
<br />
<br /> It 'lie.
<br /> 0.4.., "'0"''''0''''''''''
<br /> (I.. \Illje~ ,.."el.I>t'I.J h'd,,,.
<br />ee.....1 ".. ",)01 e/llh"i' C,....~ t'"", ".
<br />....,. 'riu., ""reu "''001'''1 ("PP'o~. ) ...('..."
<br />Appro.. Inn".. (I....t ,-, )-10:1 Scrip...
<br /><500_>10_ fU'1"..,'
<br />A~p_o.. " .. l..u.._ 111&1'1 H 1)-10:t 5~u~,., p.."",
<br />(.......croal... hutl\WI) (11.'1>'''0'' .II..d.....)
<br />>O.~ _ ",nl'" .-, 1..12 1-Doo:I Sh..dd.... <..It",....
<br /> ..'.Ir._".....,u...
<br />,,- .lpUI'" .- .,. 10-DOO'1 SII"dd...
<br /> ..'u.... .- 200~1 300: I' '"'t'dMt. ""'.r""
<br />
<br />O"'''',CO","O,,...I
<br />
<br />PU""~lnn
<br />(.." '''pro<l..~.,. I
<br />
<br />",..,.."""..
<br />(llu,oproo:hlt.,.J
<br />
<br />Iltltll... lp.ulC..ln,
<br />"'I...ocutt.t.POflI
<br />
<br />c..U" (CI'Otl)
<br />
<br />Co....
<br />
<br />)10e. I..l
<br /><l0,.), - ',,4
<br />" - .,p...." .~ I,,)
<br />" _>'0.. Up.lI,..; ""' ,.,
<br /> pro~"""1
<br /><50_)0.'_ Upuu..; ~ '-11
<br /> ,...~.." "I' ~
<br /> floe".lu._.
<br /> .<I.orpl....
<br /><0.'_ U"lr...' "'" 1-12
<br /> I...",,,.. 1,_..4
<br /> ".tn; "........ ~.
<br /> con.__ .....,u..
<br /> .n<l.ntu......
<br /> 1,,"r,.. (.rowtlll 1-0
<br />
<br />20-80:1'
<br />
<br />l/I"dd't"""p'''l
<br />
<br />'I".
<br />
<br />lIu"......~y (,.p.
<br />t..v.......dl..)
<br />
<br />P."..(F,OtlJ
<br />
<br />1-40""
<br />
<br />Collulo., (up.
<br />IlIh"""1t1
<br />
<br />l'lI..fl...(UPOtl)
<br />
<br />'-10:1"
<br />
<br />Coll..~ I ,,,' ! "'P
<br />hl,..,,,ltl
<br />
<br />Ih....I....dor.."1t
<br />_tin (001'{)
<br />
<br />>17']C
<br />
<br />_.
<br />
<br />Anl.,1I
<br />
<br />01'1
<br />(l0)
<br />
<br />'..-i.,.."
<br />
<br />",~ '0
<br />
<br />Appro.. >100_
<br />
<br />!illcro
<br />
<br />A,proll, <100...
<br />
<br />'It,,'~b"l ,ort ,.... 10-11: l.
<br />b~,... v.I~.. .,.1..<11.... III1C" ..jor portlOt\..r Ill.. ..u'...... ,......., ...y'" "i."I, b...I....~.II, "r..~'o... .. Ntll'
<br />r.no .'I"t .."till tll...... of 110"(1"" Dur..." "I,.
<br /><L.b.l. ,..tll" of DOM, ....Ieh t"",. ..." r.,.dly, ,r.......t, (11.
<br />
<br />decreasing input to about 600 g/m2/yr to higher order streams (Vannote
<br />1983). Individual inputs either significantly increase or decrease and
<br />show significant variation in organic matter loading along the continuum
<br />(Figure I).
<br />
<br />pRetention of Benthic Organic Matter (BOM)
<br />
<br />The unidirectional water flow within stream channE,ls creates
<br />~, conduit-like conditions that tend to move the organic matter received and
<br />, produced by streams. However, the unidirectional flow is off-set by a
<br />number of so-called retention structures that slow or prevent the
<br />downstream displacement of the food resource. Retention structures can
<br />"" ,~ take a variety of forms, occur at a wide range of frequencies and function
<br />
<br />~f' ~ :~o~~:~;~~e l~::;:t~:a:f;~~;::~~ ~~i~~::~~/~a~~~/~~~) ;.e ~~'~W~~~~hy~~~al
<br />
<br />~ storage, biological uptake and storage, and deposition. Benthic organic
<br />, . material may be physically retained (and stored) near Its point of origin
<br />~ and downstream movement delayed by wood debris. boulders. macroph,'I:e beds.
<br />,~ pools, etc. Reduced rate of downstream loss may result from biological
<br />. uptake in the form ~f capture, utilization, and (partial) conversion to
<br />~: biomass primarily as plant and animal tissue, but also as fecal pellets and
<br />l;ecretions commonly in the form of shells, cases. and nets. Reduced rates
<br />
<br />..
<br />~~~_u___..__
<br />. ._--~~~~:r~<~;,,'~ ~
<br />
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