144 lines
6.0 KiB
Plaintext
144 lines
6.0 KiB
Plaintext
dtyland etap.
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rath new notes that deep dtatnage plus gypsutn at
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ttntate slowlyl sulphut wt“ testete aetdte soils, taut that
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the leaehtng attt at salts that tallows may etteet sttsatn
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health tntereeptor banks leadtng to “ER at nvet lseds
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etteettvelv dean and pettntt teaching at the salted satls,
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Where the pt-t ts more than ttst gypsutn tt alsa
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tndieated ttt asststsodnttn tetnmal.
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Whetever we tmgate wtth saline waters, we tnttst
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tlush salt out at dratn the soils thatattghly, hut tn the
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end she wanders tt etapptng an sueh settls ts tnevttahly
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risky, and il dtverstpn lo enetgy ptaduettan vta nee
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etaps, at the [mp and nyadeat antntal grazing ts not a
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taettet use 0! dt-ylands tn pantculat, flood tmgatutn at
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htrntwed nelds tan result tn a ma evipomflt'e watee
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less, and a lwa» l0 seven-[um tnetease in salt mmznr
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Iriholh Salt tn ttdge and tutraw systems of need
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ttanawt ttrtgattan wtlt tnerease an the rtdges whete
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less tlttshtng aeettts, Thus, tdeatty we should need the
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ndges by cteattng heds wllh raised edges, and flush the
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salt data to the tuttaws.
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teeper tlmt nates the redueed ability 0! erapped
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satls m tnitltt—tte tatnwatet, tn adtatntng ttelds. up ta 30
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etn can he ahsettped by unenapped sells uvet a penad of
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5 hours, while tn tdentteal empped Sell, only me an
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ate ataserhed He notes that thesedtttetenets ate gteater
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than these taetween dtttetent salt types wheatctapptng
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ts thetetate at ttselt a tause ttt tneteased overland flows
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and the subsequent neadtttg 0! lower so)! ptatttes, as ts
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satl eatnpaet-ten by ovemrannx, and the use 0! hnvy
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or last taran tnaehtnery
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As [or pate spate, the speetltt gtavtty tsc.t at an
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apen sott tt (mm ”He (equal to or gteatet than an
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equal volume nt water) the s.c. ttt sull nttnetal
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CmnpflnL-ms is 1 (r3 2 thus, the avetage atr pate spaee
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tn the total valunta ts 50"» at ntnte (genuallv Matt,
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tn a "dotted statl, all ttttt a tew at these pptes ate
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walerrmledt lt that watet atsa eantatns salts, and de
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flmuhliun aeeuts, the sntl enttntt sttueture qeteltly
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ttteata dawn, and pates ate dogged wtth dtspetsed
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stlty partteles, ln wheat lands, etttly me at the salt tnav
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tse well—sttnetnted tttttnths at 0.75 ta 2 mm), whtle tn
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treedratntng ttneleated stttls, me 0! the salt ls tatn-
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pased at stteh parlichs
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Thus. tt ts elear that the sttuttttte nt satlt under
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dryland ettlttvattnn can in ttuth tateat down, and that
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almost all the Soil pate spaee dtsappeats teven thaugh
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enapptng tssttll passtttle at I2’7e entrnhstntehttel
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A may)! taetar tn satl (mmb tannattan ts the ptesente
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ol pnlysatehattdes Hottgrrham sugatst and gels
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ptadueed by lttttnus, thts hutnte tnatenal ts etttteat |n
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gaad wt] snuetute The wtdesptead ptaettee nthuttung
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dtyland gtastes and wheat stuhtate tutther teduees the
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stat htnntts Ftte ean aetttallv latte sttttaee salts sn that
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they tattn tine dusts whteh blow at wash away. tttttnus
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as green etap added ta neutral or alttaltne soils willt
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huweter, testote ettttnb snuentre it salt watet defltknh
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lattttn ean be stopped,
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tn eattapsed sells, ttw and plant rnuts tape lwu tne
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sepatattle ptatalents, even .t nat tlaaded. the reduced
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pate spaees mnlain ltttle atr, tattt tn tatns, satl tarlxtn
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dtaatde levels twaste gases hom mat respirattanl tnay
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reaeh the level at 5% ttt is lvt tn tealthy satts. and-1. tn
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air). This ts a lethal level tor plant mot growth As w¢|lt
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Eu‘phur—mncemmlmg (annembm hatterta ptetdttee
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methane and sulphur dlnxlde ttnatsh gtasat as a ttsult
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at tltedeeay ethntuus tn these anaentltte tdndtttats
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Flnilly, the weakened plant tstdts are stttnett ta taptd
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dtdttght film! by sttttate evapatattan, and taee estatmte
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sness ttptn the salt water in the soil A patnt tarnea
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where satl salts prevent water uptake by teats No
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wander we ate tttttng nees and etaps thruttghmtt the
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dwlands‘
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lt ts MW atavtaus that to plant tnes m setts alteady tn
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prtxess at eallapse ts hutle We need to stop the pm>
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eess ttt soti enllapst tttelt, and H ts here that the
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wash.” gmup have evolved what I helteve Io he a
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ttntque and stteeesstttl West Auslnhan htll tattn
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saltthan lo satl cellapse and desentneattan
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Inmmr stats
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tn earl r tnes. shallaw (0.5 tn deept comm»:
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BANKS wete tnntt la stap salt tastes an stapes, Even
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gentle slopes 0- at test lose soil tn tatn as tatntets n~
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tnttve tree COVE! Beanie lower stapes get there water,
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at flnwdown, satl etpstan ts nat ntueh less ml platns
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than it ta on htll slopes at ltr or so Content hanks dtd
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nut, hawetet. have a prntonttd etteet on WIN! etustun,
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gully tannattan. ttee death. at sotl eallapse by tlapdrng
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tndeed, salt L-vrnlually eauses eantaut bank: ta
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eollapse, and nth-dtttlpadstwer thetn tn hzavy tatns
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Although our salt pntttlents tnst appear in low (lat
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ateas and valleys. the watet that eauses the ptnlsletn
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easeades downslape The wt 5A LT appnaath is to
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tttst taettle the ptalaletn at tts sonrce~|he htll tops
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starting attaut tea tn helaw the ttdgeltnes and plateaus,
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a deep t2 rat and wdde the; tnt dtteh ts lattlldoaed up
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an eontottr Cate. tatten to that push all any tepsatl, ta
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dtg tez tn down th s ttulldaaer lalade ta break up the
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tansteted sttttsmt ttt ts otten neeedary to also rip), and
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then m eetnpaet thls elayey and stany layer by
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ramming it tirtnly against the dorm.“ taantt at the
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dtteh, utteh and pant together are called an
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INTERCEPIUR BANK trtgttte met.
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It the dawnslape bank ts :Kedivdy sealed, all htgh
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tuna" ox ttvetland flow stops at the dtteh. as does the
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slnwer seepage at thraughttaw at the tepsatl, whteh
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petehes on tap at the eantpaeted r horxznn as a
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general seepage ltne. Na floodlllg at duwnslape sotl
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results, and tutther satl eallapse eeases White the
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htghet hank; ate tnade on the level as swales, dawn.
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slape leanle slwpe at grades at 1-3000 ta natutal sheath
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tteds, and thus bath salted and Itesh water are eats-ted
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in sea tn sheaths withtn 24 veats, the stttps between
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the hunts eatnntenee to regenerate grasses, and dytng
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ttees tegatn health.
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Ma ' etseptorttanlts, stttl an mmlmlrt ate “w bulll
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every 3 at (vlflkll hetghtt downhlll ott stapes at
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“345’ at tnate, these term a eanttnuptts series at
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ditches tptped at stdnettlled mt tnaehtnet-y (Whig
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405
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