|
<br />"
<br />
<br />.
<br />
<br />?88?
<br />
<br />rACrOas AFFECTING SEDIMEHT nELD 111 M PACInC SOUTBWEST
<br />
<br />SlO'dilllent Yield
<br />
<br />A
<br />
<br />.
<br />
<br />c
<br />
<br />,
<br />
<br />.
<br />
<br />,
<br />
<br />G
<br />
<br />.
<br />LAKD EROSION
<br />
<br />I
<br />ClWfNEL EKOSIOlI &
<br />SEDIMENT TlWISPOIlT
<br />
<br /> Level.. SURFACE GEOLOGY SOlLS CLIHAIE RUNOFF TOPOCRAPHY , CllOIJND COVEll LAND USE "'
<br /> (l0)* (IO) (10) (0) (20) (lO) (10) (25) (25)
<br /> a, Marine shales a, Fill" textured; a, StOr1ll3 of several 0, High peak flows o. Steep upland lIlopes . Ground cover 40es o. Kore"than 5'0% s. Hote tlum 501 of a, Erodius banks con-
<br /> and related mud- easilydispeued; days' dutati<lll per unit areS (in exc.ella of 30%) tIOt ezeeed 201~ cultivated the area cbar- tinuously or at
<br /> stolles and 811t- saline-alkaline; IIithshor:tperlods >, LarllevolUllllOof KiSh relief; 11ttl." ...Vegetation.parae; b, AIllIOat all of acl;-edzed by rill frequent intervals
<br /> 1118h stones. high $hdllk-swell of intense r.lo- flolfp<"runlt or no floodplain Uttleo!:" no 8'tealntenalvely 811dllllllyor vith large depths aud
<br /> characteristics. fall. area developaumt litter Irazed lapQslideero$ioD lonl flow duratiop
<br /> b, Sipgle lrain sUts b, Frequent intense 0, All of area re- b, Ac:tiveheadcuu and
<br /> and fine sand.s convective stot1llS b. No tack ill surface centl)' burned degradation in tdb-
<br /> 11011 uury channels
<br /> <, Freeze-thaw
<br /> occurrence
<br /> ..
<br />i
<br /> (5) (5) (') ('l (10) (0) (0) (10) (10)
<br /> a, Rockll of mediUlll a, Medium textured &, StormsofllOder- s. Moderate peak 0, Moderate upland Cover not exceed- 0, Less than 25% 0, About 25% of the 0, Hoderate flow depths,
<br /> hardness soU ate duration and nOtols slopes (less. than ing 40% cultivated area character- lIed1U11l flow duraUon
<br /> b, Moderately b, Occa$ional rock intensity b, 20%) 0, Noticeable litter b, 50%orleasre- bed b)' rill and ..ith occasionall}.
<br /> Moderate volume . gully or 1..nd- eroding banks orbed
<br /> Moderate weathered frapetlts b, Infrequentcon_ of flow per unit b. Koderat~ faD or b, If tree. present cently 10Ued
<br /> 0, Moderately frac- <, Caliche layen vective storu area floodplain develop- undentory not <, Less than 50% .1n- slide erosion
<br /> tured ~"' well developed teasivelygrued b, Wind er-oa1ol> with
<br /> d, Or-.Unary road and deposition in
<br /> other construction atr-eaIII channels
<br /> .. . I
<br /> (0) (8) (0) (8) (0) (-10) (-10) (0) (0) I
<br /> ", .x..~sl.ve, hard 0, High percentage 0, HlDIIid c:liSlate with 0, Low peak flows 0, Gentle upland &, Area completely a, Noc:ultivation o. Ho apparent s1ftnS 0, Wide shallow chanllels
<br /> for_tiom. of rock fragments raiafa..lof lw per unit area slopes (lesa than protectedbyveg- b, No recent 108liag of erosion with flat gradienta.
<br /> b, Aggregated e1ays intensity b. Low volume of '" etation, rock <. Low intensity short flow duration I
<br /> Low Precipitation in ftapeats, litter
<br /> <, High in organic b, runoff per unit b, Exteoaive alluvial gradng b. Ch.annels ia IUII:l,ive J
<br /> IlUttter fora of SDOW area plaill$ Little opportunity rnet.. large boulden; i
<br /> e. Arid cl1aat.e, low <, Il.ar-e runoff for raiofall to .or well vegetated ,
<br /> inteusityatoJ:lllS eventa reach erodible c. Artificially controlled.l
<br /> d. ~::d. c~~t~~ rar~ ..terial .~l.,' :
<br /> ,
<br />
<br />.. THE NUMBERS III SPECIFIC BOns UDIChTE VALUES TO BE ASSIGNED APPROPRIATE. CIlARACTEKISnCS.
<br />THE SHALL LETTERS a. b, C, 1tEFER. roo INDEPENDENT CftARACTERISTICS TO WHICH fULL VALUE HAY BE ASSIGNED.
<br />.... IF EXPERIENCE SO INDICATES. INTERPOlATION BETWEEN THE 3 SEDIHEKr YIELD LEVELS KAY BE KADE.
<br />
|