Calibration of QUAL2K model in Brazilian micro watershed: effects of the land use on water quality

Transcription

1 At Limnologi Brsiliensi, 2010, vol. 22, no. 4, p oi: /tl Clirtion of QUAL2K moel in Brzilin miro wtershe: effets of the ln use on wter qulity Clirção o moelo QUAL2K em um miro i rsileir: efeitos o uso e oupção o solo n qulie águ Flávi Bottino 1, Ive Ciol Ferrz 2, Euro Mrio Meniono 1 n Mri o Crmo Clijuri 1 1 Deprtmento e Hiráuli e Snemento, Esol e Engenhri e São Crlos, Universie e São Pulo USP, Av. Trlhor São-Crlense, 400, CEP , São Crlos, SP, Brzil e-mil: flviottino@yhoo.om.r; emm@s.usp.r; lijuri@s.usp.r 2 Deprtmento e Meio Amiente - Coorenori e Reursos Hírios, Av. Prof. Freerio Hermnn Jr., 345, préio 12, 3º nr, CEP , Pinheiros, São Pulo, SP, Brzil e-mil: ive@miente.sp.gov.r Astrt: Aim: This stuy ime to evlute the wter qulity of Cnh River miro wtershe (Rieir e Igupe Vlley, São Pulo Stte, Brzil) n to lirte the QUAL2K moel with fiel t; Methos: Five vriles of wter qulity were nlyze (wter temperture, issolve oxygen, ph, eletri onutivity n turiity), s well s flow n veloity, in eight smpling sttions from Septemer, 2006 to July, It ws performe orreltion test etween oserve t n simulte t; Results: The issolve oxygen onentrtion ws high (over thn 5.0 mg.l -1 ) uring smpling perio. The hewter presente the lowest onentrtions of this vrile. The eletri onutivity i not exee 80 µs.m -1 n the ph i not rnge (0.5 1). The hyruli vriles were in greement with River Continuum Conept. Although orreltion test ws not suessful for some vriles, the simulte t followe oserve t; Conlusions: The rinfll linke to ln use ws importnt for otine results. The wtershe hrteristis, s high slope, for exmple, were essentil minly to issolve oxygen onentrtions. Even though QUAL2K hs some limittions its use is reommene for wter resoures mngement n future purposes. Keywors: moeling, QUAL2K, wter qulity, ln use, rzilin wtershe. Chemil Limnology Resumo: Ojetivo: O presente estuo teve por ojetivo vlir qulie águ miroi o rio Cnh (Bixo Rieir e Igupe, São Pulo, Brsil) e lirr o moelo QUAL2K om os os otios em mpo; Métoos: Form nliss ino vriáveis e qulie águ (tempertur águ, oxigênio issolvio, ph, onutivie elétri e turiez), em omo vzão e veloie e esomento, em oito pontos mostris urnte setemro e 2006 julho e A omprção entre os os simulos e oservos foi feit trvés e um teste e orrelção simples; Resultos: As onentrções e oxigênio issolvio form lts (im e 5,0 mg.l -1 ) urnte too o períoo e mostrgem, seno que n nsente oservrm-se s menores onentrções. A onutivie elétri não ultrpssou 80 µs.m -1 e o ph teve um pequen fix e vrição (0,5 1). As vriáveis hiráulis seguirm teori o Continuum fluvil. Os os simulos seguirm mesm tenêni os os oservos, emor o teste e orrelção não tenh sio stisftório pr tos s vriáveis; Conlusões: A preipitção pluviométri li à moifição o tipo e uso e oupção o solo form os prinipis responsáveis pelos resultos otios. As rterístis i, omo lt elivie, por exemplo, tmém form importntes, priniplmente pr s onentrções e oxigênio. Emor o moelo QUAL2K tenh lgums limitções, seu uso pr gerenimento os reursos hírios e proposts e enários futuros é reomeno. Plvrs-hve: moelgem, QUAL2K, qulie águ, uso e oupção o solo, miro i rsileir.

2 2010, vol. 22, no. 4, p Clirtion of QUAL2K moel in Brzilin Introution The growing rte of the popultion hs use remrkle inrese of the emn for nturl resoures ue to suh proesses s urniztion, griulture n inustriliztion. The iret onsequenes refer to the quntity n qulity of the ville freshwter to humn onsumption. Due to prolems relte to wter resoures it is essentil to improve monitoring, reserh n mngement tions in orer to ensure their effetive mnging. (Clijuri n Buel, 2006). In this regr wter qulity moels hve een use s n importnt tool (Bongrtz et l., 2007; Fng et l., 2008; He et l., 2008; Srinh et l., 2008). These moels re le to preit wter qulity vritions in long n short term linking them to hyrology, river hyruli n ln use. Furthermore some humn tivities n mge quti life n therefore hrm the eosystem lne. This wy moels n hrterize lterntives to support the evlution of ifferent results. Despite the importne of mthemtil moeling on wter qulity reserhes it is essentil tht the moel e ritilly hosen. There re lot of moels ville ut the most pproprite is the one tht meets the reserh ojetives. The QUAL2K moel is the new version of the wiely use QUAL2E. QUAL2K is istriute y USEPA (Unite Sttes Environmentl Protetion Ageny, 2007) n it is se on ifferentil equtions for one-imensionl systems n stey stte flow. This moel is effiient to simulte wter qulity n hyrologil onitions of strems s well s systems with iffusive pollution los. Prk n Lee evelope QUAL2K in orer to orret the QUAL2E limittions. Therefore QUAL2K hs mny new elements; it is useful in t limite onitions, is freely ville n re not reserve for lrge rivers (i.e. eep n wie). Some reserhes use QUAL2K to simulte wter qulity (Prk n Lee, 2002; Knnel et l., 2007) ut in Brzil these stuies re unusul. The present reserh ime the evlution of the wter qulity of miro wtershe use to puli supply tht is unergoing moifitions of ln use. Moreover the lirtion of QUAL2K moel ws performe with the Cnh River t. 2. Mteril n Methos 2.1. Stuy re The miro wtershe of the Cnh River is into the Rieir e Igupe Wtershe tht is lote in the south of São Pulo Stte. This wtershe preserves gret prt of the remnnt re of the Atlnti forest. It is uner ontinuous proess of egrtion ue to the elerte urn growth, eforesttion n inustril tivities (Clijuri et l., 2003). The Cnh River is roun 27.5 km long n it flows through regions of ense forest n nn plnttions. It rosses Jupirng s rurl zone n flows into Jupirng River next to the Sewge Tretment Plnt (ltitue: ; longitue: ). The verge ltitue of the Cnh River oes not exee 200 m. The topogrphy is slightly restrite. As for geology there re preominnt Plins n Wve-Cut Terres. On peology there is preominne of Hpli Cmissol (Clijuri et l., 2003). Aoring to Clijuri et l. (2007), the soils of the region re onsiere with high suseptiility to erosion. The Cnh River is use to puli supply, whih inrese the importne of etermining oth the wter qulity n the hrteriztion of the miro wtershe s one Smplings Smplings were rrie out in ifferent perios (Septemer 2006, Jnury, April n July 2007) in eight smpling sttions long the longituinl xle of the Cnh River (Figure 1). The flow n veloity mesures were performe oring to Righetto (1998). For etermintions of the wter temperture, eletri onutivity, ph n turiity, multiprmetri proe n turiimeter were use. Dissolve oxygen (DO) ws mesure oring APHA (1999). The smples were ollete in wter su-surfe (10 m uner the wter level). All the smpling sttions presente men epth lower thn 1m, inluing the perio of higher rinfll. The moel use in the stuy ws QUAL2K, me ville y the USEPA, whih ws lirte with the fiel t of the Cnh River, suh s flow, slope, ottom with, wter height, smpling sttion istne n wter qulity vriles (wter temperture, eletri onutivity, ph, solis, DO n nutrients). Aoring to QUAL2K mnul (Chpr n Pelletier, 2006) the prmeters (reertion oeffiient, settling oeffiients, DO onsumption, proution, et) were insert in the spresheet of moel to fit the lirtion. The river ws segmente oring to the ln use. The Tle 1 presents this ivision s well s the lol hrteristis. The ivision of elements

3 476 Bottino, F. et l. At Limnologi Brsiliensi Rorim Ampá Are Amzons Prá Rononi Tontins Mto Grosso Cerá Mrnhão Piuí Bhi Rio Grne o Norte Prí Pernnuo Algos Sergipe Gois Mins Geris Mto Grosso o Sul Espirito Snto São Pulo Rio e Jneiro Prná Snt Ctrin Brzil Rio Grne o Sul São Pulo Stte N W E Sete Brrs Juqui Itnhem Monggu Pero e Toleo Mirtu Itriri Peruie S Eloro Registro Igupe Priquer-Açu Jupirng Brr o Turvo Ilh Compri Cnnei Rieir Cnh Wtershe Cnh River Smpling sites Figure 1. Shemti mp showing Rieir e Igupe Wtershe, São Pulo Stte, Brzil, n Cnh River Wtershe with smpling sttions. Fonte: IBGE (2000). Tle 1. Representtion of the simulte segments. Segment En segment Distne (km) Chrteristis Hewter Rurl re 3 Riprin forest/livestok Rurl property Rposo frm 6 Livestok/nn rop Rposo frmer SP 222 Ro 15.2 Bnn rop/urn Are ws me se on the istne etween smpling sttions n is represente in the Tle 2. The hyruli vriles lirtion ws performe oring the following proeures: i) Flow: it ws use the men flow n the ifferene etween ownstrem flow n upstrem flow ws onsiere s iffuse soure. Aoring to QUAL2K moel stey-stte flow is implemente for eh moel element s (Eqution 1): Qi = Qi 1 + Qin,i Qout,i (1) where: Q i = outflow from element i into the ownstrem element i + 1 (m 3-1 ); Q i-1 = inflow from the upstrem element i-1 (m 3-1 ); Q in-1 = totl inflow into the element from point n nonpoint soures (m 3-1 ); Q out,i = totl outflow from the element ue to point n nonpoint withrwls (m 3-1 ). ii) To wter veloity: the moel lultes the epth n the veloity in one of three wys:

4 Clirtion of QUAL2K moel in Brzilin Tle 2. Representtion of simulte elements. Elements Reh (km) weirs, rting urves, n Mnning equtions. This stuy ws performe using Mnning eqution. The men veloity of eh element ws use in the moel n its lirtion ws rrie out oring to the wtershe slope n n of Mnning for nturl hnnels. Uner onitions of stey flow the Mnning eqution n e use to express the reltionship etween flow n epth (Eqution 2): Q S = 01/2 A 5/3 n P 2/3 (2) where: Q = flow (m 3 s -1 ); S 0 = ottom slope (m/m); n = Mnning roughness oeffiient; A = ross setionl re (m 2 ); P = wette perimeter (m). The moel lso provies list of Mnning roughness oeffiient. This list s well s the lssifition of Rosgen (Rosgen n Silvey, 1996) were use in this stuy. iii) The wter qulity vriles were lirte using t of the ifferent smplings n the ifferene etween ownstrem t n upstrem t ws onsiere s iffuse soure. The temperture moel tkes into ount het trnsfer from jent elements, los, withrwls, the tmosphere n the seiment. A het lne n e written for n element s (Eqution 3): T Q = i 1 Q Q out,i E' T i + i 1 i 1 Ti Ti ( Ti 1 Ti) t Vi Vi Vi Vi E' 3 + i Wh,i m ( Ti+ 1 Ti) + ρ 6 3 (3) Vi wcpw Vi 10 m Ji m J + + si m ρwcpwhi 100m ρwcpwhi 100m where:t = temperture in element i ( C); t = time (); E i = ulk ispersion etween elements i n i+1 (m 3-1 ); W h,i = net het lo from non point soures into element i (l -1 ); ρ w = the ensity of wter (g m -3 ); C pw = the speifi het of wter [l (g C) -1 ]; J,i = the ir-wter het flux [l.(m -2-1 )]; J s,i = the seiment-wter het flux [l.(m -2-1 )]. Aoring to QUAL2K mnul (Chpr n Pelletier, 2006), the ph of river is ompute se on equilirium of ron n lklinity. The onutivity is relte to inorgni suspene solis. In regr of the issolve oxygen, it n inrese ue to plnt photosynthesis n lost vi Croneous Biohemil Oxygen Demn (CBOD) oxition, nitrifition n plnt respirtion. Depening on whether the wter is unersturte or oversturte the DO is gine or lost vi reertion. The progrm lultes the DO oring to Eqution 4 elow: So = rophytophoto + robota lg Photo rofstoxi ronnh4nitr rophytore sp rophytore sp robota lg Re sp + Ox Re er (4) where: rophytophoto = phytoplnkton oxygen proue (g O 2-1 ); robotalhphoto = ottom phytoplnkton oxygen proue (g O 2-1 ); rofstoxi = O 2 require for ron ey (go 2 gc -1 ); ronnh 4 Nitr = O 2 require for NH4 nitrifition (go 2 gn -1 ); rophytoresp = phytoplnkton oxygen onsumption (O 2-1 ); rophytoresp = phytoplnkton oxygen onsumption (go 2-1 ); robotalgresp = ottom phytoplnkton oxygen onsumption (go 2-1 ). The inexes (ro, ro, ro, n ron) re prmeters n the vlues use were suggeste y Chpr n Pelletier (2006) (Eqution 5). Ox Re er = k (T)(o s (T,elev) o) (5) where: k (T) = the temperture-epenent oxygen reertion oeffiient ( -1 ); o s (T, elev) = the sturtion onentrtion of oxygen (mg O 2-1 ) t temperture, T, n elevtion ove se level, elev. iv) The prmeters require y the moel (see spresheet Rtes of the moel) were fit oring vlues reommene y mnul of moel (Chpr n Pelletier, 2006) suggestions were employe to lirtion. These t re wiely use on literture n n to e foun in the mnul of the moel. The output t of moel re grphis of the limnologil vrile (onentrtion) versus istne. However in this reserh these grphis

5 478 Bottino, F. et l. At Limnologi Brsiliensi were reme (onentrtion versus hnnel length [%]), in orer to fvor unerstning n isussion of results. For flow t the grphis showe the flow (L.s -1 ) versus hnnel length (%) n in the seonry xis ws use speifi flow (L.s -1 km -2 ). The reltionship etween fiel mesurements n simulte vlues ws performe using orreltion test. 3. Results In Brzil, espeilly in São Pulo Stte, the riny seson is from Otoer to Mrh. However, 2007 ws n typil yer with intense preipittion in July (67 mm seven ys efore the smpling). Higher flows were oserve in July from 19 L.s -1 (hewter) to 4619 L.s -1 (mouth) n lower flows were reore on Septemer (spring) from 14 L.s -1 (hewter) to 595 L.s -1 (mouth). Consiering the speifi los, the higher vlues were otine in hewter n lower in the mouth uring ll sesons (Figure 2). The flow lirtion in the QUAL2K moel ws suessful n the orreltion test etween oserve t n simulte t showe men R 2 = There ws wie vrition of veloity (Figure 3), minly in river meium ourse, whih is insie of rurl properties. The sptil vrition ws higher in the spring n lower in the summer, with vlues rnging from 0.11 to 0.73 m/s n 0.16 to 0.39 m/s, respetively. The highest veloity vlues were otine in the winter n the lowest ones in the utumn. In reltion to simultion the orreltion ws suessful (R 2 = 0.95) As expete, the lowest wter tempertures were reore in the winter n utumn n the highest ones in the summer n in the spring (Figure 4). Consiering the orreltion test, it ws possile oserve in winter R 2 < 0.7 n for the other sesons the men vlue ws 0.9. Regring DO, the lowest onentrtions ourre in the hewter, with inreses t the meium river ourse. During the summer, utumn n winter perios were oserve slight erese of DO in the smpling sttion 5 (meium river ourse). Derese of vlues ws lso foun in smplings sttions ner to the river mouth in ll sesons The highest DO onentrtions were reore uring the winter, n the smpling sttion 4 (meium river ourse) presente the highest vlue of ll sites (9.1 mg.l -1 ). The lowest DO onentrtions ourre uring the summer (hewter: 5.93 mg.l -1 ), followe y utumn n spring (Figure 5). Although orreltion test ws not suessful (R 2 = 0.98 in spring n R 2 < 0.7 for ll sesons) the simulte t followe the oserve t. The eletri onutivity inrese from upstrem to ownstrem in ll sesons (Figure 6). The vlues oserve in the spring n in the summer were quit similr. On the other hn, higher longituinl vrition n lower onutivity vlues were foun uring the winter smpling. Correltion test presente R 2 < 0.7 for spring n utumn, in the summer R 2 ws 0.9 n in the winter the vlue ws 0.8. The ph vlues i not presente longituinl vrition however temporl vrition ws oserve (Figure 7). During the perio of higher rinfll (July) there ws smll erese of ph with vlues etween 5.82 (smpling sttion 8) n 6.06 (smpling sttion 3). In this reserh, this vrile h low vrition (0.5 1). For ph the orreltion nlysis ws unsuessful euse R 2 vlue ws < 0.7 for most of perios. Just in the spring the R 2 ws 0.7. In ll smplings, exept in July (winter), the turiity vlues erese from the hewter to the mouth. The lowest vlue ws reore in Septemer (spring) smpling (Figure 8) n the highest uring in July. It s importnt to mention tht turiity is not n input n output t for the QUAL2K moel simultion. Therefore, the present stuy oes not show the simulte t for this vrile. 4. Disussion Cnh River flow n veloity ynmis followe the River Conitnuum Conept (Vnnote et l., 1980). During ll sesons these vriles presente temporl ptterns, with ontriution of ringe ynmi, minly ue to the high slope ner to the hewter. In ition, the sene of point soure of pollution long the river suggeste ontinuity of the flow n the veloity. The QUAL2K moel oes not use the rinfll s n input t, however the hyruli vriles hve gret orreltion with hyrologi t. This wy the lirtion of flow n veloity my e use to nlyze rinfll ptterns. Moreover, the lirtion wy of these vriles ws suessful. Glrith n Burns (2007) reporte tht the wtershe size, its slope, s well s the hyrology n ln use hve n importnt role in the wter qulity. Thus, it mens tht the wter qulity vriles of the Cnh River re strongly relte to ln use of its thment. The smpling sttions lote in the highlns re surroune y vegettion (out 90% of forest), refleting ifferenes in wter physil

6 Clirtion of QUAL2K moel in Brzilin Figure 2. Flow vrition in Cnh River (inferior siss, left orinte) n speifi flow vrition in the wtershe inrement (superior siss, right orinte), uring the spring ( - Septemer), summer ( - Jnury), utumn ( - April) n winter ( - July) perios, respetively. : oserve flow; : oserve speifi flow; : simulte speifi flow.

7 480 Bottino, F. et l. At Limnologi Brsiliensi Figure 3. Veloity vrition (m/s) in Cnh River, uring the spring ( - Septemer), summer ( - Jnury), utumn ( - April) n winter ( - July) perios, respetively. : oserve veloity; : simulte veloity. Figure 4. Wter temperture vrition (ºC) in Cnh River, uring the spring ( - Septemer), summer ( - Jnury), utumn ( - April) n winter ( - July) perios, respetively. : oserve wter temperture; : simulte wter temperture. n hemil vriles. However, in lowlns n in the meium river ourse the vegettion ws prtilly or totlly remove (out 15% of res with griulture n 40% of urn re). As result, hnges were oserve in the vlues of limnologil n hyrologil vriles. The wter temperture of the Cnh River is in greement with the theory propose y Vnnote et l. (1980) too. As expete, lower tempertures were oserve in res with remining riprin forest. Rivers surroune y forest hve lower wter temperture ue to show. Moreover, smller rivers re suseptile to the lrgest

8 Clirtion of QUAL2K moel in Brzilin Figure 5. Conentrtions of issolve oxygen (mg.l -1 ) in Cnh River, uring the spring ( - Septemer), summer ( - Jnury), utumn ( - April) n winter ( - July) perios, respetively. : oserve issolve oxygen; : simulte issolve oxygen. Figure 6. Eletri onutivity vrition (μs.m -1 ) in Cnh River, uring the spring ( - Septemer), summer ( - Jnury), utumn ( - April) n winter ( - July) perios, respetively. : oserve eletri onutivity; : simulte eletri onutivity. temperture vrition (Vnnote et l., 1980). Cnh River is miro wtershe n its triutries re until thir orer, therefore the wter temperture my e influene y wtershe hrteristis. Aoring to Wetzel (1983) the oxygen soluility in quti systems is relte to temperture. This ft ws oserve in the Cnh River with higher onentrtion reore in July. Cnh River presente DO onentrtions over thn 5.0 mg.l -1 uring ll stuie perio. These high onentrtions shoul e relte to high slope n wter veloity. However, it ws importnt to note tht uring ll sesons, the smpling sttion 1 presente low onentrtions of DO. In utumn were reore the

9 482 Bottino, F. et l. At Limnologi Brsiliensi Figure 7. ph vrition in Cnh River, uring the spring ( - Septemer), summer ( - Jnury), utumn ( - April) n winter ( - July) perios perios, respetively. : oserve ph; : simulte ph. Figure 8. Turiity vrition (NTU) in Cnh River, uring the spring ( - Septemer), summer ( - Jnury), utumn ( - April) n winter ( - July) perios, respetively. : oserve turiity. lowest onentrtion in hewter (5.9 mg.l -1 ). This result my hve ourre ue to orgni mtter from the riprin forest. The influene of orgni mtter on this vrile ws oserve y Srinh et l. (2008) tht reporte reue DO onentrtion in Meio strem (Leme ity, São Pulo Stte, Brzil) with effluent ishrge input. Although the DO onentrtion ws low in hewter of Cnh River, this vlues re high (men of 7.0 mg.l -1 ) when ompre with Cintr River in Brzil (4.4 mg.l -1 ) (Bellut et l., 2009) n Meio strem (1.5 mg.l -1 ). Aoring to Groppo et l. (2008) the mjor ontriution for oxygen epletion is urn growth.

10 Clirtion of QUAL2K moel in Brzilin The urniztion removes the riprin forest esies it ontriutes to input of the sewge n inustril effluent. In espite of sene of riprin vegettion long the Cnh River, the oxygen onentrtions were high in ll smpling sttions. The ereses were higher in meium river ourse uring summer n utumn. The equtions showe in the mnul of QUAL2K moel show oxygen onsumption y BOD, ut in the eqution of issolve oxygen lne this onsumption is not showe. However is not possile to know if this is n error in the mnul or if the lne of issolve oxygen hs filure. Srinh et l. (2008) use QUAL2K moel to simulte the DO in Meio strem. The uthors onlue tht the moel ws onsistent sine the oserve t were fitte with the simulte t. Similr results were otine to Cnh River. The eletri onutivity provies informtion out the metolism of the quti eosystem, showing the reltion mong wters, wtershe geologil formtion n llohthonous mteril input. Donohue et l. (2006) stuying the reltion mong hemil vriles of rivers in Ireln n the eologil sttus of its wtershe note tht the eletri onutivity ts s n importnt initor of wtershe ln use. The longituinl vrition of the eletri onutivity ourre from upstrem to ownstrem in the Cnh River. In ll smpling perio the highest onutivity ws reore in river mouth exept in utumn. This result my e relte to the low rinfll in this seson. Higher eletri onutivity ws lso foun in Cintr River (Brzil) uring ry seson (Bellut et l., 2009). In ition the high onutivity vlues in river mouth (ner urniztion) my e ssoite with input of mteril s lnestine sewge n litter. Mrques et l. (2007) suggeste tht in ry perio there re low onentrtions of issolve ompouns in wter ue to sene of runoff. As result the wter qulity n e etter, lthough in the riny seson the ilution effet improves the river onitions. Cnh River presente lowest eletri onutivity uring riny seson, proly ue to ioni ilution. Regring the QUAL2K moel, there is no mention to the lultion of the eletri onutivity, however it is relte to the suspene inorgni solis. The hewter of the Cnh River presente the lowest ph n the vlues were similr in ll smplings (etween 5.0 n 6.5). The eomposition proesses of vegettion in hewter my e erese the ph vlues. Similr ptterns were foun in Córrego Rio Wtershe (Tquriting ountry, São Pulo Stte, Brzil) tht showe lowest ph in preserve hewter (Donio et l., 2005). The temporl vrition ws in greement with stuy evelope in Rieir e Igupe wtershe with low ph vlues in riny perio (Mrques et l., 2007). It is importnt to highlight tht the ph lirtion in the QUAL2K moel hs iniret reltion with phytoplnkton respirtion; however, no t referent to the lge were lirte t the present reserh, whih my use ifferene etween simulte n oserve vlues of ph. During the winter it ws registere mximum vlue of turiity (60 NTU) next to the river mouth. This ft my e relte to the high rinfll tht ourre in this perio n promote the llohthonous mteril input n resuspension of seiment. The results otine for Rieir e Igupe wtershe were similr (Mrques et l., 2007) with highest vlues oserve uring riny seson. Oliveir et l. (2008) foun 60 NTU in hewter of the Moeneis Strem (Limeir ountry, São Pulo Stte, Brzil) n onlue tht sene of riprin forest ws essentil for this result. The input of llohotonous mteril n resuspension of seiment my improve the longituinl vrition of the turiity in the rier perios. Roy et l. (2003) nlyzing environmentl nswers ue to the ifferent types of ln use in the wtershe of the Etowh River, Georgi, verifie tht the turiity ws relte to the inrese of the urn n griulturl res n erese of the forest overge. In the Cnh River, espite of urn e griulture evelopment in their mrgins, the iffuse soures input seems oes not influene the turiity vlues yet. The QUAL2K moel hs some struturl n funtionl limittions suh s performing simultions in non-permnent wy n the impossiility of to hnge the internl struture of the moel, i.e., insert equtions tht etter represent the relity (Gonçlves, 2009). Despite this informtion, the moel hs een wiely use for wter qulity ssessment. In this reserh QUAL2K showe some limittions, ut the simulte t followe the oserve t (lthough it ws oserve R 2 < 0.7 for some vriles). The orreltion test ws suessful for hyruli t, ut some moel input t (lge respirtion, lge eth or seiment emn) o not llow suitle reltionship for limnologil t suh s oxygen n ph.

11 484 Bottino, F. et l. At Limnologi Brsiliensi The grphs showe in this stuy (% of length or % of wtershe re) llow omprison etween ifferent reserhes in eosystems with ifferent sizes. Furthermore it provies more effetive eision for eh wtershe segment with issimilr ln use n the los linking quntittive n qulittive spets, n effiient pproh for wter resoures mngement. 5. Conlusion The im of this stuy ws to evlute the wter qulity of the Cnh River miro wtershe se on the wter physil n hemil vriles nlysis n in its ln use. QUAL2K moel ws employe for lirtion fiel t. This moel is use for smll rivers with stey stte flow onitions. The riprin forest in the hewter ws the min ftor tht use ifferentitions in the vlues foun for the physil n hemil vriles, s well s, its removl to inlue the nn ulture n the proximity with the urn re of Jupirng influene the vlues foun in the meium river ourse n ownstrem. In these smpling sttions DO onentrtions erese n eletri onutivity inrese. There ws not importnt ph vrition long the river n turiity presente longituinl vrition from hewter to river mouth in ll sesons. The eletri onutivity n turiity ws relte to low rinfll n ph vlues with high rinfll. Flow n veloity were relte to rinfll n it is in greement with the River Continuum Conept propose y Vnnote et l. (1980). The onentrtions of issolve oxygen were elevte uring ll stuy, ue to high slope n sene of point pollution soures. Overll, it s possile to onlue, from fiel t, tht the Cnh River is not pollute ut the onstnt hnge in ln use my hrm the wter qulity. For this reson it is neessry to re-evlute the sttus of this river oring to the Brzilin legisltion. The QUAL2K moel provie stisftory result to the lirtion with the smpling t of the Cnh River. Nevertheless mny prmeters n pplitions presente in the moel re ssigne to tempere environments, whih my ompromise the lirtion of some vriles. Moreover some onsiertions in mnul progrm re not suitle. However, the QUAL2K moel is reommene for wter qulity simultion in orer to mintin n effetive mngement of the wter resoures n propose future senrios. Referenes Amerin Puli Heth Assoition - APHA. Stnr methos of the exmintion of wter n wstewter th e. Wshington: APHA. BELLUTA, I., SILVA, AMM., CAMARGO, CHC. n RALL, VLM Impts on the springs of Cintr Strem (Botutu, São Pulo Stte, Brzil) n ownstrem vrition in wter qulity. At Limnologi Brsiliensi, vol. 21, no. 1, p BONGARTZ, K., TIMOTHY, DS., BABOROWSKI, M. n LINDENSHMIDT, KE Monitoring, ssessment n moeling using wter qulity t in Sle River Bsin, Germny. Environmentl Monitoring Assessment, no. 135, p CALIJURI, ML., LOURES, SSP., SANTIAGO, AF., SCHAEFER, CEGR., LUGÃO, WG. n ALVES, JEM Ientifição e áres lterntivs pr isposição e resíuos sólios n região o Bixo Rieir e Igupe, SP. Engenhri Snitári e Amientl, vol. 12, no. 3, p CALIJURI, MC. n BUBEL, APM Coneitução e mirois. In: LIMA, WP. n ZAKIA, MJB., es. As Florests Plnts e Águ. São Crlos: Rim Eitor. p CALIJURI, MC., MENDIONDO, EM., VARESCHE, MBA., VAZOLLER, RF., DOMINGOS, MD, DOS SANTOS, ACA. n CALIJURI, ML Estuos os sistems nturis e rtifiiis reutores e rgs poluiors pr sustentilie os reursos hírios o Bixo Rieir e Igupe, SP. Projeto temátio FAPESP. CHAPRA, SC. n PELLETIER, GJ QUAL2K A moelling frmework for simulting river n strem wter qulity. Mefor: Doumenttion n users mnul Civil n Environmentl Engineering Dept Tufts University. DONADIO, NMM., GALBIATTI, JA. n PAULA, RC Qulie águ e nsentes om iferentes usos o solo n i hirográfi o Córrego Rio, São Pulo, Brsil. Engenhri Agríol, vol. 25, no. 1, p DONOHUE,.I, GARRILÉ, ML. n MILLS, P Linking thment hrteristis n wter hemistry with eologil sttus of Irish rivers. Wter Reserh, vol. 40, p org/ /j.wtres FANG, X., ZHANG, J., CHEN, Y. n XU, X QUAL2K moel use in wter qulity ssessment of Qintng River, Chin. Wter Environmentl Reserh, vol. 80, no. 1, p org/ / x GALBRAITH, LM.n BURNS, CW Linking ln-use, wter oy type n wter qulity in Southern New Zeln. Lnspe Eology, no. 22, p

12 Clirtion of QUAL2K moel in Brzilin GONÇALVES, JCS Desenvolvimento e moelo numério pr simulção qulie águ em rios utilizno o softwre Vensim PLE. São Pulo: Universie e São Pulo. [Mster Thesis in Hyruli Engineering n Snittion]. GROPPO, JD., MORAES, JM., BEDUSCHI, CE., GENOVEZ, AM. n MARTINELLI, LA Tren nlysis of wter qulity in some rivers with ifferent egrees of evelopment within the São Pulo Stte, Brzil. River Reserh n Appllitions, vol. 24, p HE, H., ZHOU, J., WU, Y., ZHANG, W. n XIE, X Moelling the response of surfe wter qulity to the urniztion in Xi n, Chin. Journl of Environmentl Mngement, no. 86, p KANNEL, PR., LEE, S., LEE, YS., KANEL, SR. n PELLETIER, GJ Applition of utomte QUAL2Kw for wter qulity moeling n mngement in the Bgmti River, Nepl. Eologil Moelling. no. 202, p MARQUES, MN., COTRIM, MB. n PIRES, MAF Avlição o impto griultur em áres e proteção mientl, pertenentes à i hirográfi o rio Rieir e Igupe, São Pulo. Quími Nov, vol. 30, no. 5, p OLIVEIRA, VM., SILVA, MSG., MEDEIROS, CB., JESUS, VE., PIO, EGM., PILLON, JF., LIMA, RP., BOMBO, AL., GODOY, BL., DETONI, AD., CONTER, P., BARONI JUNIOR., M., FRANCISCO, AR., BADDO, B., BROTA, GA. FILHO, JLP., OLIVEIRA-NETO, AL., ALMEIDA, G., ROSSINI, AJ. n PELEGRINI, RT Avlições físis, químis e iológis miroi o Córrego Moeneis em Limeir SP. Engenhri Amientl, vol. 5, no. 1, p PARK, SS. n LEE, YS A wter qulity moeling stuy of the Nkong River, Kore. Eologil Moelling, vol. 152, p RIGHETTO, AM Hirologi e Reursos Hírios. São Pulo: Eitor EDUSP. ROSGEN, D. n SILVEY, HL Applie river morphology. 2th e. Coloro. ROY, AH., ROSEMOND, AD., PAUL, MJ., LEIGH, DS. n WALLACE, JB Strem mroinverterte response to thment urniztion (Georgi, U.S.A.). Freshwter Biology, v. 48, p x.oi.org/ /j x SARDINHA, DS., CONCEIÇÃO, FT., SOUZA, ADG., SILVEIRA, A., JULIO, M. n GONÇALVES, JCSI Evlution of the wter qulity n uto-purifition from the Meio Strem, Leme (SP). Engenhri Snitári e Amientl, vol. 13, no. 3, p Unite Sttes Environmentl Protetion Ageny - USEPA. Aville from: < Aess in: 14 mr VANNOTE, RL., MINSHALL, GW., CUMMINS, KW., SEDELL, JR. n CUSHING, CE The River Continuum Conept. Cnin Journl of Fisheries n Aquti Siene, vol. 1, no. 37, p Reeive: 19 Ferury 2010 Aepte: 03 June 2011