Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | , and 1,2,3 Sciences Discussions ect of the eco- ff Earth System Hydrology and , D. Y. Wang 1,2,3 , T. L. Qin 1,2 10466 10465 , G. Wang 1,2 , H. H. Li 1,2 , H. Wang 1,2,4 1,2 This discussion paper is/has been under review for the journal Hydrology and Earth System Sciences (HESS). Please refer to the corresponding final paper in HESS if available. State Key Laboratory of Simulation and Regulation of Water CycleWater in Resources River Department, Basin, China Institute of Water Resources and Hydropower Environmental Science and Engineering Department, Donghua University, Shanghai, School of Hydraulic Engineering, Dalian University of Technolgoy, Dalian, 116023, China evaluation of the impact ofof the the project on water the resource water areaenvironmental circulation was impacts and conducted. ecological of evolution The theconcentrated research western on results route two were aspects, project asphase i.e. follows: in of the the dam the construction permanent water and destructionhydrological river resource situation of impoundment, area of and vegetation natural the were during river significant corridorIts the influence after impact on the the on implementation of local waterthe climate, transfer. water vegetation environment ecology, of typical river wetlands, basins natural below reserves the and dam sites was small. simulation model was used toof imitate the the laws water of ecological resourcesis and area and environmental quantitative in change evaluation a wasscheduling, changing placed representative on climate. the river reservoir corridors The constructionter and emphasis and environment wetlands, of operation of natural influence reserves river analy- and basins the below wa- the dam sites. In the end, an overall influence besides, global climate changelogical causes impact the of uncertainty water andenvironmental transfer additive projects. impact e Therefore, of how large-scaleoperation to has water assess triggered transfer the a lot ecological projects ofChina’s and in South-North attention. Water The both Transfer water-output Project construction area wasarticle. of taken and the as western the According route study of area toanalysis of the on relevant present the evaluation eco-environment principlesfied of and and the evaluation on indexes study were the area, established. basis the The influence of climate-hydrology-ecology factors coupled background were identi- The interbasin long-distance water transferallocation project of is water a resources key inporal support a change for large-scale of the area, water reasonable which resourcessources. can to And optimize large-scale reinforce water the the transfer spatiotem- projects guarantee have of a the deep influence access on of ecosystems; water re- Abstract Hydrol. Earth Syst. Sci. Discuss.,www.hydrol-earth-syst-sci-discuss.net/8/10465/2011/ 8, 10465–10500, 2011 doi:10.5194/hessd-8-10465-2011 © Author(s) 2011. CC Attribution 3.0 License. L. H. Wang 1 China Institute of2 Water Resources and Hydropower Research, Beijing, 100038,Research, China Beijing, 100038,3 China 201620, China 4 Received: 19 October 2011 – Accepted:Correspondence 9 to: November 2011 G. – Wang Published: ([email protected]) 30 NovemberPublished 2011 by Copernicus Publications on behalf of the European Geosciences Union. Quantitative analysis on the ecological impact of large-scale water transfer project on water resource areachanging in environment a D. H. Yan 5 25 15 20 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | , 2003; Ghassemi and White, ff et al., 1997; Rosenberg et al., 1997; Friedl 10468 10467 ff cient, and the negative influence of projects in the phase of ffi ¨ uest, 2002; Brismar, 2004; Burke et al., 2009). What’s more, the environmental In the present article, some explorations of the evaluation of the ecological influence Oversize water transfer projects, especially those which cross rivers and are of long typical wetlands and natural reserves; and (4) evaluate the influence of water transfer 2006). of the western routeducted. project This on study its aimsroute to water-output project of contributing area SNWTP to in will show impactand a how, on regions ecology and changing and related to climate environment what to in areevaluate water extent, water resource the con- the transfer. area influence western The ofresource specific the area; objectives (2) reservoir of evaluate construction the thisof influence on paper typical of the water-reduction are water river transfer local to on reaches; climate (1) the (3) of hydrological evaluate situation the the influence water of water transfer on operation is becoming increasinglyNorth significant. Water Transfer The ProjectTibet western (SNWTP) Plateau, route locates which is of its theof China’s water-output sensitive South- the area area of ecological in global influence thetriggered climate evaluation Qinghai- change. a of Therefore, lot studies this of area concerns are (Yang of et great al., importance 2002; and Berko have certain aspect of thetransport ecological patterns influence, and such biodiversity as (Morais, theOuyang 2008; hydrological et Hu situation, et al., al., pollutant 2011), 2008;area, or Koutsos water-intake they et area al., are and 2010; the targeted riverand at delta Cantera, a (Xu 2011). certain et al., And area, 2011;the the such Ligon environmental climate as et impact change assessment al., the of 2011; aspect water-output large Restrepo hasexperiences water of transfer been existing projects. inadequately water Judging transfer treated from projects, in the theand estimation environment of their is impact insu on ecology (Petts, 1984; Casadoand et W al., 1989;and Po ecological influence ofextremely project complex, under thus the there backgroundare of short is global of considerable global, climate uncertainty. comprehensive change and is Present systematic relevant research as studies they are focused on a and therefore impose a broad array of impacts on the ecosystems of a river basin distance, are all huge systematic projects. They have a large span of space and time (Yang, 2003; Wang, 2009).mental Besides, influence studies of on water evaluation transferfield of projects (Doledec, ecological have 1996; gradually and developed Bombino environ- intocompanied et an by al., important the 2006; aggravation of Shahthe the and global ecological Kumar, climate influence 2008). change, of thebecome Meanwhile, evaluation the increasingly concerning ac- valued, water and transfer aand project Moura, few 2009; in studies Olden in a and thisPittock Naiman, changing field and 2010; environment Doll Finlayson, were and 2011). has carried Zhang, out 2010; (Zeilhofer Moiwo et al., 2010; ecological influence caused byal., those 2008; projects Kittinger (Graf, etWu 2006; al., et Morais, 2009; al., 2008; Baran 2010;specialized Braatne and Olden in et Myschowoda, and the 2009; construction Naiman, Grownslished and 2010). et so the al., as At operation 2009; to of the mitigate water same and transfer time, projects even laws prevent were and the pub- ecological regulations and environmental problems projects. From 1940tion to of 1980, large-scale long-distance the interbasin2009). world water After transfer witnessed 1980, projects with the (Yang, the 2003;became uprising peak Wang, consciousness cautious period of of environmental of the protection, people the constructionconcerning the of construc- negative water ecological transfer impacts projects ofprojects both and (Davies construction a and et series operation of al., ofcountries these reports all 1992; over the Meador, worldtransfer 1992; began projects, Nardini, to and conduct 1997) carry ecological came out influence evaluation thorough out. on researches water on Since environmental then, problems and With the increase ofindustry the and world’s the population, increasing urbanization, theter the rapid uneven resource development spatiotemporal and distribution of of its agricultureresource wa- and quality to deteriorate. economic development, To many cope countries with have the undertaken serious water limitation transfer of water 1 Introduction 5 5 25 15 20 10 25 15 20 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | – 0 20 ◦ 10470 10469 N. It covers seven counties in three provinces, 0 20 ◦ –33 0 30 ◦ E and Longitude 31 0 10 ◦ First of all, background analysis on the eco-environment of the study area is con- The water-output area of the western route project is an ecologically fragile region In the end, awater comprehensive resource influence area assessment on ison the conducted. the ecological local The evolution climate of evaluationlogical and the covers situation; vegetation; five (3) (2) aspects: influence influence onof on (1) wetlands; natural typical influence (4) reserves; river influence and corridors onbelow (5) and the the influence hydro- dam climate on sites. and the hydrology water environment of typical river basins tion indexes are determinedthe based eco-environmental on evolution relevant laws evaluationronment criterions. of imitated the Then, by water based the resourcefluence on climate-hydrology-ecology area analysis coupled in and simulation a quantitative model,construction evaluation, changing and the the envi- operation in- emphasis scheduling, of typicalreserves which river and the corridors, are water typical the environment wetlands, of reservoir river natural basins below the dam sites, are performed. According to the characteristicsticle of attaches large-scale water special transfer importancetween projects, projects to the and the present the interrelation ar- correlation amongof all evaluation. and kinds In of superimposed view ecological of influence factorswater the in transfer be- strategic the project level, process is the integrated construction in and the operation evaluation of system. the whole ducted based on existing meteorological,and hydrological, the soil and data vegetation collected information by field survey. And the influence identification and evalua- hydrological control plan so astion to and give operation reasonable of guidance the to project. the planning,2.2 construc- Main considerations and the focus of the evaluation changing climate is of great significance for putting forward a scientific and systematic degrees on the eco-environmentan and objective society eco-environmental evaluation and of economy the of western route this project area. on the To area carry in out a section of the upperand reaches in Marke of and Chuosijia Akeof River, section Dadu the River. of Seven the west water upper branchare: transfer reaches reservoirs of Reba, are of the scheduled Aan, Zumuzu to River, Dadu Renda,rangement be the River, of Luoruo, constructed, east the Zhuanda, which branch western Huona route and project. Keke. Figure 1as shows well the as ar- thethat ecological the shield construction of and running the of upper the stream project of would Yangtze impose River. an It influence of is various probable Province, Rangtang and Aba County ofin Aba Sichuan Tibetan and Province Qiang and autonomousGansu prefecture Maqu Province. County of The Gannan damupper Tibetan reaches sites of autonomous of the prefecture waterper Yalong in transfer River’s reaches are mainstream, of in located the Daqu in Xianshuihe and Ganzi River, Niqu section a section at branch of of the the the up- Yalong River, in Sequ and Duke 2 Materials and methods 2.1 Study area The first-stage of westernof route the project Qinghai-Tibet of102 SNWTP Plateau, is with locatedi.e. the at Banma geographic the County southeast coordinatesDege, edge in of Guoluo Ganzi, Latitude Tibetan 99 Seda autonomous county prefecture of of Qinghai Ganzi Province, Tibetan autonomous prefecture in Sichuan aspects above are basedduced upon in a Sect. simulation 2.5. andmodel forecast However, itself for platform are saving which focused space, will on the be in assessment this intro- results article. other than the on water environment below the dam sites. The quantitative assessment of the four 5 5 15 20 10 20 25 15 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | 10472 10471 erent typical areas for evaluation, are chosen from the above-mentioned ff simulation platform Therefore, the present article gives evaluation on the following three scales: South- changes on the water circulationis and the the ecology key and to environment of the the forecast related area of transferable water amount in the process of operation water-reduction river reaches (river corridors)age below area the above the dam dam sites sites. and the water2.5 stor- Key supporting technology: climate-hydrology-ecology coupled To identify the influence of the westernof route the project of water SNWTP resource onas the area eco-environment well is as the the premise focus of of the arguments planning of and stakeholders. design And of meanwhile, the prevision project, of the above Yibin, the emphasison of local evaluation water is circle placed andclimate on vegetation, change the the and influence role of the ofecological climate local influence environment; change underlying of on surface the water change scaleis transfer in of on focused the the on the area the local of important influence water influence, of circulation the climate and evaluation change and project construction on the typical located in a sensitivethe area to project climate including change, somegory the areas III-C area belonging area). of to climate Category change III imposed should by be includedeast (Cate- Asia, Yangtze River BasinFig. above 3). Yibin andof On the global area the of climate Southeast importantthe change Asia influence underlying on scale, (see surface the the on local main the environment consideration climate and is change; the put on influence to the of the scale changes impact of in Yangtze River Basin global change (Category Iented area), to local i.e. water the resourcesabove allocation Southeast (Category Yibin; Asia; II and area), (ii) (iii) i.e.water medium-scale the the catchment Yangtze area river apparent above basin ori- the influence dam areariver site section (Category (Category below III III-A the area), area) dam which and site typical (Category includes water-reduction III-B area). In addition, since the project is resource area can be divided into three categories, (i) large-scale area oriented to Taking into account the particularof geographical the location western and route of ecological SNWTP, characteristics the influence of the western route project on the water of the western routetarget level, project. which can These basicallyof indexes meet the can the water demand give resource of area aboutaiming the of 70 at eco-environmental the % di diagnosis western information route of project.8 Furthermore, the diagnostic relevant indexes indexes andtransfer used project on to the give eco-environment quantitative in all analysis typical of areas. 2.4 the influence of Evaluation water scope laws in the waterenvironment resource of area the and area. theportance And influence of through of all further indexes water and selectionaccessibility transfer their by of on relation taking the the with information, into ecological the 4 accountin water primary the Table transfer 1, indexes im- project, and are 8 as determined secondary well to as indexes, act as the as shown the diagnostic indexes of the ecological evolution ladder model is built toanalytic form hierarchy a process general is indicator employed system. tothe Then, mark structural the the judgment 1–9 importance matrix scale of for method thethe the in indexes environment. possible and influence Five build of primary the indexes areare western chosen atmosphere, route by water, project analytic creature, on hierarchy soil, process, naturaldexes which disaster based and on soil the deterioration. five primary Andthe indexes 32 ecological are in- evolution determined of to the form westerndexes the chosen route indicator from project system the area. of indicator In system the are end, used direct to relevant determine in- the ecological evolution Firstly, the present articlegeography, atmosphere, employs hydrology, 8 soil, primary biology, populationaster indexes and and and economy, natural 137 soil dis- secondaryterization deterioration indexes of in of the order ecological to environment give of the a upper comprehensive stream and of objective Yangtze River. charac- And a 2.3 Evaluation index system 5 5 25 15 20 10 25 15 20 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | . The wind speed in spring 1 − ciency and service condition of the ffi ects e ff 10474 10473 ected. In future climate scenario, the influence on wind speed is in- ff , is the most significant. In future climate scenario, the project has some ◦ in the northwestof of the the high water temperatureof resource area the area in seasonal decreases Chengdu distribution, while Plain it the in has central the been value observed east that, increases. after In the terms construction of Influence of the reservoirresource construction area. on the localIn energy process historical of climate thespeed background, water in the summer, autumn reservoir andis construction winter by hardly increases 0.3–0.8 a m the s significant, wind while the influence oncant, the which humidity is field reflected at by thein the location decrease the of of 2 Sichuan m humidity region is in in signifi- the the northwestIn east. and historical increase climate background,the the spatial reservoir distribution constructiontemperature of has is no local as influence follows: average after on in temperature. spring, the autumn construction and of The winter the increases,of temporal and reservoir, 0.15 that the change in temperature winter, of with aninfluence annual on increase the spatial distribution of local temperature: the low temperature area Verification of the model in terms of multiple process and scale is listed in Table 3. Under the demand of practical needs, we firstly clarify the mechanism of mutual 1. mate (2040–2049). The resultsthe of construction the of experiments indicated thetemperature, the reservoir following which had conclusion: means little thatundergo influence significant the on change the climatic in wind fielddegree. the speed, of The future. humidity results the However, are and local water specified rainfall as resource will follows: area increase will to some not were set up: theexperiment control B experiment (current A climate with (currentwithout the climate the reservoir), without reservoir) contrast and the experiment contrast C reservoir), experimenthorizontal (future contrast D climate resolution (future climate of with the the reservoir).separate mode periods: The was situation 30 km of and historical climate the (1993–2002) modeling and was situation carried of out future cli- in two scenarios of underlying surface with or without the reservoir. Four sets of experiments Based on Regional Climate Model,tion a on study the on local the climate influence of of the the water reservoir resource construc- area was conducted by setting up two From the verification result, itquantitative can evaluation be of seen that theand the influence environment. model of can meet the the western demand route of the project on local ecology 3 Results and discussion 3.1 Quantitative evaluation on the climate of the water resource area advantages of eachclimate-hydrology-ecology model coupled simulation (Table (Fig. 2), 4), themodular and modeling technology. is under In performed using the the end,unified guidance the physical coupled mechanism. of simulation platform the was framework developed with of a water circulation, ecology and environmenttify of the the main water mechanism resourceit area; of can (2) mutual it objectively action can characterize among iden- ecological the climate, and key hydrology environmental driving and evolutions; mechanism and ecology;circulation, in (4) eco-environmental (3) the evolutions it in water can a circulation simulate comprehensive and the regulation changes context. in water action among energy flow, natural-social waterthe circulation, and carbon ecological process circulation (with as the main line). Then, by giving full play to the simulation project. The keyquire technical the supports development of for a theforecast climate-hydrology-ecology two coupled platform practical simulation with model needs unified anddrology, mentioned mechanism a meteorology/climate above and based ecology. re- on The simulation thefollowing platform multilayer functions: should observation possess (1) on the it hy- can give historical analogue simulation and forecast on the scheduling of the project, which directly a 5 5 25 15 20 10 25 15 20 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | in winter. ◦ ered from the ff water in the first-stage of the western 3 10476 10475 ered from the impact to the most extent in June, ff the reservoir, the localdecreases in temperature spring will and autumn. rise It in increases summerInfluence by of approximately and the 0.28 winter reservoir construction and on slightly In the general, local the water circulation. average annualthe rainfall future climate of scenario, the the reservoir averageIn annual area terms rainfall tends increases of to by about the increase. 22ter, seasonal mm. In spring distribution and of autumn, rainfall,significant. and rainfall Rainfall that tends in in to summer spring, decrease increases by in with about win- a 7 %. decrease of 19 %, is the most With the convergence of water flow from the dam cross-section to the river delta, the 2. with the dam construction begins,widened the water in level the goes river up and reachs the belonging river to cross-section the is backwater area of reservoir, which might weakened. In both drydownstream season flow and below the wet dam season,width sites, at with cross-sections the the of flow remarkable river speed, decrease will water significantly of depth decrease. the and3.3 water surface Quantitative evaluation of the influenceThe on dam typical construction wetlands for water intakewhile has no its influence influence on wetlands on below the those dam above site, the dam site is uncertain. After the water storage ment area below theriver dam reaches sites, rises, the quantity whichindexes of means is water decreasing. the flowing The impact into waterprocess of the transfer of the has water-reduction water flood significant influence transfer season,frequency on on which of the river flood is hydrological hydraulics peaks. mainlyinflow, While reflected the with influence by of the the the increase decrease water of transfer in water on catchment both the hydrologic area flow process and and of water river is gradually 86.3 % of that before the water transfer. 3.2.2 Influence on river hydraulics indexes After the construction of reservoirs,as with well the as decrease the of correspondingand the decrease downstream surface of channel water area flow depth, of flowwithin the speed, the water water-reduction river surface river course width reaches might (see be influenced. Fig. Meanwhile, 5), with the the water increase ecology of the catch- ration that the flow offor control many cross-sections at years the tends lowerflow to reaches at recover takes Lianghekou in gradually of the after totalof Yalong the River that flow water before after the transfer. the water waterChuosijia The transfer; and River transfer cross-section cross-section and can flow Zumuzu be at River restored river after delta to the of 55.2 water % Xianshui River, transfer can be restored to 76.6 %– site decreased by 92.1 %;water and transfer project the in Zumuzu May. River system was most influenced by the mean monthly flow formost many significant years; influence the of the Xianshuiof water River Aan transfer system project and in also Renda June, su reservoirsyears, and decreased in the by June, discharged 88.1 % compared flow and withsystem, 89.6 the %, where respectively; mean the the Luoruo monthly Sequ reservoir flow Riverfer is of for located, Chuosijia project many River was in most influenced October,River, by with the where water its Zhuanda trans- reservoir mean isproject monthly located, in flow was June, decreased most with by influenced the 83.6 by mean %; the monthly the water flow Dukehe transfer of the downstream reach below the dam route project, the channelafter flow the of construction themonthly of downstream distribution water section of will transfermain significantly discharged reservoir stream decrease water is of flow the completed.and Yalong after River the su the Combined discharged with reservoir flow of the water Reba transfer, reservoir the in June accounted for only 11.0 % of the 3.2 Quantitative evaluation on typical water-reduction3.2.1 river reaches Influence on the water amountAccording of to downstream river the reaches diversion plan of 8 billion m 5 5 25 15 20 10 20 25 15 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | ect can ff erent 5 ff can meet 5 of Ake River can meet 5 erent. With consideration ff ect above the dam site is enhanced, ff ect on the biodiversity. Besides, with the ff -N can meet the standard II, with annual 3 10478 10477 -N can meet the standard II. In February of dry 3 -N can meet the standard II. The results indicated and NH 3 Mn and NH of Ake County section in 2020 and 2030 slightly exceed 5 Mn and NH Mn erent target years is listed in Table 7. ff ective pollution control, the water quality of the county town can rise by 1 ff main river reaches below the dam sites below the dam sites For other river reaches, even without pollution control, the water quality ofAfter other the water transfer, the ammonia nitrogen concentration of various river reaches In detail, after the water storage of reservoir begins, it is estimated that 1651 hectares of the water transfer reservoirscentration after at the the water upper transfer reaches. still exceeds Even the though classification the demand of ammonia Standard con- II situations and in di seven rivers in theII, three with target no years change afterwater in the transfer. categories water of transfer water can quality still compared meet to Standard at the the situation before initial the stagesignificantly of decreases the by 27 raining %–41 %. season, compared This is to mainly that caused before by the the water purification transfer, e the standard I, and itsseason, COD except that the BOD the standard II (in linestandard with the I, standard and III), its under COD that, other with conditions, its e BOD to 2 levels. Water environment quality evaluation of Ake River section under di For the Ake River section,meet in the the standard three target I,average years flow and after and COD the without water considerationbefore transfer, of the BOD pollution water control. transfer, Comparedwater the quality to estimated above the and change situation below is Abaof County minor. on pollution Ake In control, River is February all di that of estimation without dry indexes show consideration season, significant offlow, improvement in pollution compared the control. three to target years Under after the the water context transfer, of the BOD annual average 3.5.1 Quantitative analysis of the influence on the water quality of 3.5 Quantitative evaluation of the influence on water environment isfy their need and nothe major influence damage of will the be western caused. route The project comprehensive on evaluation of natural reserves is listed in Table 6. level will lead to the submergenceby of some the fish, torrent all habitats ofincrease and which of spawning will the places exert reservoir required adverse wetland e area,formed new to eco-hydrological provide patterns new of wetland habitatsin will for population, be species. which increases Waterfowls and thebegins, biodiversity wading the to birds discharge some will flow degree. increase below After theto the dam the water site storage decrease will of be significantly availablecounty reduced, water and which in Kasha leads such Lake. natural But reserves the as water Xialatuo available Area in in these Luhuo two zones can basically sat- the water transfer on thebiodiversity forest of vegetation, the the water ecosystem resource area. below the dam siteof and forest the land andlead 2561 hectares to the of destruction shrub ongus forest wild resources. land animals, In will plateau addition, rare be fish medicinal submerged, migration resources route which and is could wild blocked fun- by dam and the rise of water Table 4. In order toecology give a and reasonable evaluation environment, of the theclimate influence evolution scenario of with trend this or of project without on wetland the both western landscape route pattern3.4 project in is analyzed future (Table 5). Quantitative evaluation of the influenceThe on influence natural of reserves the westernthe route project change on of natural reserves water lies quantity in the and impact the of both submergence of the reservoir area caused by riverside wetlands: the situationinto the of opposite. wetlands At the supplyingthus same the time, the the river flooding flooding bed e wetlandincreases could area be the is turned wetland increased areamodel and calculation, above even the the new evaluation dam wetland of site. is the formed, western Based route which on project on theoretical wetlands analysis is and listed in cause changes in the groundwater recharge relationship between the river flow and 5 5 25 15 20 10 25 15 20 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | ected factors ff ect of the reservoir ff ), the purification e 1 − erent control sections is reduced by 13 %– ect on the category of water quality in the ff ff 10480 10479 -N at di 3 , NH Mn ected by the western route project as well as the a ff , the impact of the project on water circulation and water ecology of the 3 of the cross-section at the county town approximately. The influence on thetion climate of has the little waterThe influence resource climate area: on of the the the water reservoirconstruction wind resource of construc- the area speed, reservoir, generally but the has thegree. no local humidity In rainfall major indeed the and changes increases future after to the climate a the situation, certain temperature. the de- annual average rainfall will rise by 22 mm erent scales of space, namely, the Souteast Asia, the river basin above Yibin and As is indicated by the evaluation results, under the planning water transfer of Quantitative and qualitative analyses are both employed in the evaluation of the west- 1. ff di the area of the most influence. The conclusions are as follows: Based on the actual needsof of the the western evaluation route of project ecological ofhydrology-ecology SNWTP and coupled in environmental a simulation influence changing model, climateclimate, the and typical supported present river by article, corridors, climate- typical by wetlands,ment focusing natural of reserves on and river local the basins water below environ- the dam site, has undertaken quantitative analysis in three tation caused by theproject; land the occupation permanent during destruction thegence of caused implementation vegetation by of in the the the water storage;river reservoir water the corridors area transfer influence via after on the the theaspects, hydrologic submer- water situation namely, water transfer of quantity is original of significant, river which channel, is river width mainly and reflected water in depth. three 4 Conclusions influence distribution map ofand the 7. western route project is drawn, as8 billion shown m in Figs.water 6 resource area is focused on three aspects: the permanent destruction of vege- Based on the results of comprehensive evaluation, the comprehensive environmental area. On the basis ofmated single-item evaluation, by threshold expert value estimation of system, influence and degree the is influence esti- levels are classified respectively. Based on analysis and evaluation results previouslytypical stated, landscapes ecology a and environment of and influence degree aresignificant listed influence in on Table flow 8.at speed, the All river water in resource width all, area,wetlands, and while the natural water the reserves western depth influence and route on of water project local environment the below climate has river the and a dam corridors vegetation, site typical ern is route limited. project SNWTP on water circulation and eco-environment in water resource main stream of Yalong River.River The is environment high capacity enough of thattowns both after will Make not the River exceed water and the transfer Duke environment the capacity pollution of discharge county3.6 in town the river county section. Quantitative evaluation of the comprehensive influence After the water transfer, watervironment inflow capacity from of the COD upper32 stream %. is reduced; However, hence theduction the surplus caused en- by environment the capacitydischarge water remains of transfer. the high two Before even county orto with towns after the along some the the environment re- main water capacityindicates stream transfer, of of that the Yalong river the River pollution reach is water far at transfer inferior the has no cross-section e of county town. This (the standard limit valuetends of to which reduce is the 0.5initial mg ammonia l stage pollution of in raining the season, and river the reaches water below quality3.5.2 the is dam significantly enhanced. site Capacity at influence the analysis and sensitivity analysis on the environment 5 5 20 25 15 10 25 20 15 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | ect ff ects of check-dams ff 10482 10481 ers from reduction to a certain degree, which is, ff This study is jointly funded by the National Key Project of Scientific and , J.: China: The South-North Water Transfer Project – is it justified?, Water Policy, 5, ff seven sections in three target yearscontrol, after the can water transfer, still even withoutcompared meet pollution to the that before II theof water water transfer. ammonia standard, In nitrogen addition, withconcentration with of no the of the purification ammonia changes e water at insections transfer the shows water initial reservoir an quality stage apparent at decrease of the by raining 27 upper %–41 season %. in reaches, all the of the river inferior to the IIIall water of the standard. estimationconsideration indexes When of of pollution water pollution control quality control. is decrease compared taken to into For that account, other without sections, the water quality in the The influence on typicalof wetlands: overland there flow is rechargingwetlands generally type above no below the impact the dam on damwetlands site the site. recharging is wetlands the However, river uncertain. the basinsthe influence is It area transformed on is into of the possible wetland opposite. above that the Meanwhile, the dam situation siteThe increases of influence after the on the construction naturalis of reserves: dam. estimated after that the 4212-hectaredegree storage of forests of damage will water to beincrease in the submerged, in the biodiversity wetlands, which reservoir, in new it wetland cause thehabitats ecological natural certain for patterns reserves. species. are formed However, Afterreserves to with at the provide the the new water lower transfer reaches su however, begins, not water severe enough supply to in cause the any natural seriousThe damage. influence on the waterpollution quality control, at the the water lowerthe reaches: quality water with of transfer no the can considerationdry Ake meet of season, section the in the II three water water target quality standard. years of after But the in river February reaches when below it’s Ake in County might be The influence on typical river corridors:reservoir is after completed, the the construction stream of flowdecrease, the below accompanied water the by transfer the reservoir reduction will of gosuch mechanics through indexes a of as sharp the river the course, watersurface area. depth, the This reductionthe flow results river rate, course. in the a Withthe water certain the ration inflow surface impact that of width on the water water the andwater from flow water transfer of the the ecology the takes dam water control of in section sectionsthe to the at project the overall the on river water lower the delta, reaches flow hydrological after dynamics tends the of to the recover river and tends the to be impact weakened. of riparian ecosystems: a reviewthrough of Hells research Canyon, strategies Environ. and Manage., their 41, relevance 267–281, to 2008. the SnakeAssses., River 24, 59–87, 2004. on riparian vegetation inexample application, the Ecol. mediterranean Eng., environment: 27, 134–144, a 2006. methodological approach and Health, 12, 227–234, 2009. 1–28, 2003. In general, the major environmental impacts of the western route project of SNWTP 3. 5. 2. 4. Brismar, A.: Attention to impact pathways in EISs of large dam projects, Environ. Impact Braatne, J. H., Rood, S. B, Goater, L. A, and Blair, C. L.: Analyzing the impacts of dams on Bombino, G., Tamburino, V., and Zimbone, S. M.: Assessment of the e Berko Baran, E. and Myschowoda, C.: Dams and fisheries in the Mekong Basin, Aquat. Ecosyst. Technical Supporting Program (GrantFoundation Programme No. of 2006BAB04A08) Natural Science and Foundation Innovation of Research China (Grant Group No. 51021066). References lies in the permanentand destruction river of impoundment vegetation during asof the well the phase as river of corridors theclimate dam after apparent and construction vegetation, the impact typical implementation wetlands, on natural of reservesthe the and water dam water hydrological sites transfer. environment below is situation Its limited. influence onAcknowledgements. local 5 5 25 20 15 10 25 15 20 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | ect of ects or ff ff , in press, 2011. ects of dams, Bio- ff e macroinvertebrate ffl ects of a water supply ff a River delta, the Colombian ı ´ ects of large dams on American rivers, ff 10484 10483 doi:10.1016/j.jsames.2011.04.006 , 2010. ngton, J. M.: Application of a hierarchical framework for as- ffi ¨ uest, A.: Disrupting biogeochemical cycles: consequences of damming, Aquat. n?, Environ. 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Eng., 33,holistic 233–241, evaluation 2008. and assessment: linkingGorges ecosystems Dam, and Ecohealth, human 6, well-being 601–613, for 2009. the Three and mapping impacts on threateneddam species construction, in Ecol. regions Eng., adjacent 36, to 1017–1027, Natura 2010. 2000 sites due to exploitation on the hydrology3026–3039, and 2010. water storage in Baiyangdian Lake, Hydrol. Process.,opment 24, in an IberianJ. basin Lim., (SW-Europe): 44, 105–117, focus 2008. on the Guadiana estuary, Ann.diguill Limnol.-Int. reservoir (Tallowa Dam) on downstreamassemblages water in quality, substrate the and Shoalhaven ri River, Australia, Mar. Freshwater Res., 60, 594–606, 2009. States, Canada, China, and India, Cambridge Univ. Press, New York,Geomorphology, 2006. 79, 336–360, 2006. science, 45, 183–192, 2011. analysis of ecologically relevant riverdoi:10.5194/hess-14-783-2010 flow alterations, Hydrol. Earth Syst. Sci., 14, 783–799, Sci., 64, 55–65, 2002. basin water transfers, and theirserv., threats 2, to 325–349, river 1992. basin integrity and conservation, Aquat. Con- communities after the completionnatural of change? three Arch. hydroelectric Hydrobiol., schemes: 136, 19–40, anthropogenic 1996. e an irrigation and hydroelectric275–284, 1989. reservoir on its downstream communities, Regul. River., 4, sessing environmental impacts ofrecruitment dam operation: of Changes riparian in224–236, trees streamflow, 2009. bed in mobility a and western North American river, J. Environ. Manage., 90, ¨ oll, P. and Zhang, J.: Impact of climate change on freshwater ecosystems: a global-scale Wang, G. Q.: World water transfer projects, Beijing, Science Press, 2009 (in Chinese). Restrepo, J. D. and Cantera, J. R.: Discharge diversion in the Pat Po Shah, Z. and Kumar, M. D.: In the midst of the large dam controversy: objectives, criteria for Pittock, J. and Finlayson, C. M.: Australia’s Murray-Darling Basin: freshwater ecosystem con- Rosenberg, D. M., Berkes, F., Bodaly, R. A., Hecky, R. E., Kelly, C. A., and Rudd, J. W. M.: Petts, G. E.: Impounded rivers: perspectives for ecological management, Chichester, UK: Wi- Olden, J. D. and Naiman, R. J.: Incorporating thermal regimesOuyang, W., into Hao, environmental F. H., flows Song, as- K. Y., and Zhang, X.: Cascade Dam-Induced Hydrological Dis- Nardini, A., Blanco, H., and Senior, C.: Why didn’t EIA work in the Chilean project canal laja- Kittinger, J. N., Coontz, K. M., Yuan, Z. P., Han, D. J.,Koutsos, Zhao, T. M., X. Dimopoulos, F., G. and C., Wilcox, and B. Mamolos, A.: A. P.: Toward Spatial evaluation model for assessing Morais, P.: Review on the major ecosystem impacts caused by damming and watershed devel- Hu, W. W., Wang, G. X., Deng, W., and Li, S.: The influence of dams on ecological conditions Moiwo, J. P., Yang, Y. H., Li, H. L., Han, S. M., and Yang, Y. M.: Impact of water resource Growns, I., Reinfelds, I., Williams, S., and Goade, G.: Longitudinal e Meador, M. R.: Inter-basin Water Transfer: Ecological Concerns, Fisheries, 17, 17–22, 1992. Graf, W. L.: Downstream hydrologic and geomorphic e Ghassemi, F. and White, I.: Inter-Basin Water Transfer: Case studies from Australia, United Ligon, F. K., Dietrich, W. E., and Trush, W. J.: Downstream ecological e Friedl, G. and W D Doledec, S., Dessaix, J., and Tachet, H.: Changes within the Upper Rhone River macrobenthic Davies, B. R., Thoms, M., and Meador, M.: An assessment of the ecological impacts of inter- Casado, C., Carcia de Jalon, D., Delolmo, C. M., Barcelo, E., and Menes, F.: The e Burke, M., Jorde, K., and Bu 5 5 25 30 20 15 10 30 25 20 15 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | cient 0.1344 ffi coe ff biodiversity index 0.1117 Area of wetlandRun-o γ 0.1656 10486 10485 Water 0.4631Creature Ecological 0.2270 flowDisasters and soildeterioration 0.1418 Soil erosion modulus 0.1745 0.1199 Environmentally and ecologically diagnostic indexes of the western route of SNWTP. the Manso dam: Impact2009. analysis and suggestions for mitigation, Ecol. Eng., 35, 105–117, nese). ation of West Route Area11–18, of 2002 Interbasin (in Water Chinese). Transfer Project, Acta Geographica Sinica, 57, Project on net primary productivity2011. in the reservoir area, Sci. Total Environ., 409, 4656–4662, run-of-river dams on benthic2010. diatoms in the Xiangxi River, China, Aquat. Sci., 72, 117–125, Target levelEcological and hydrologicalcontrol of the water Atmosphere resourcearea 0.1681 of the western routeSNWTP of Annual average temperature 0.0922 Criterion level Index level Annual rainfall Dryness of atmosphere 0.0938 Weight of index 0.1078 Table 1. Zeilhofer, P. and de Moura, R. M.: Hydrological changes in the northern Pantanal caused by Yang, S. T., Liu, C. M., Yang, Z. F., Sun, R., and Zhou, X. D.: Natural Eco-environmental Evalu- Yang, L. X.: Foreign water transfer projects, Beijing, China Water Power Press, 2003 (in Chi- Xu, X. B., Tan, Y., Yang, G. S., Li, H. P., and Su, W. Z.: Impacts of China’s Three Gorges Dam Wu, N., Tang, T., Fu, X., Jiang, W., Li, F., Zhou, S., Cai, Q., and Fohrer, N.: Impacts of cascade 5 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | 0.72 0.75 cient ≥ ≥ ffi the study requirement 4.27.4 – – 10.35.29 8.27 – 6.89 – ≤ ≤ 13.65 – ≤ ≤ ≤ ≤ ≤ 0.65 0.89 0.85 0.81 0.90 0.86 0.70 0.780.78 – – – – cient inaccuracy (%) coe horizontal process of the water circulation and ecological process is left out. ≥ ≥ ≥ ≥ ≥ ≥ ≥ ≥ ≥ ffi coe 10488 10487 ff ff -N 3 NPP NPP Temperature Vegetation type COD NH Essential factors process, underground process,natural hydrological processsuch of as water overland resources flowconcentration and channel flow are takenconcentration, based into social on account; hydrologic criteria bothprocess of technology intake, transportation, using, consumption and vertical anddrainage horizontal and provide optimized basic data of river competition for processes light, are consideredreproduction, species invasion, habitat,bioclimatic such process, as death water and level, soil organic materialdecomposition, simulation of flow quantity,the flow growth speed and and succession of vegetation DSSATenvironment capacity evolution simulate flux natural model; vegetation DGVM can water depth growth and succession; DSSAT environmental succession quantitatively evolutions ecological and process can and simulate to crop growth identify and along river sections. Multi-process and step-by-step verification result of the model. Simulation process of essential factors and the selection of prototypes. ScaleLarge-scale Variable Rainfall Medium-scale Run-o Small-scale Correlation Run-o Relative Nash Ecologicalprocess Net initial productivity, material distribution and transportation, GeoPro, CLM, DGVM and GeoPro mode is based on leafWaterenvironment scale; CLM It contains is canopyprocess able to transformation realize process basic of Transportation and simulation of pollutants, ecological pollution load and dynamic model of water quality transportation and One-dimension transformation of pollutants It is able to simulate the simulation of environment water It is able to realize basic Basic process Selection of process of Prototype selection Characteristics of the modelWatercirculationprocess Satisfaction degree of evaporation and transpiration, Canopy interception, Earth surface water process, Reasonable soil allocation model dynamics process WEP of simulation ecological and process no circulation simulation and to natural-social water It is inaccurate in energy It is able to realize Energyflowprocess Earth surface radiation process, flux, soil CWRF, RegCM3 sensible canopy heat heat flux, flux, latent etc. heat It is good at the simulation of It is able to realize the energy taken into account energy; and only the vertical process is process modeling of all the layers. Table 3. Table 2. Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | ected by the project. ff Restorability Irreversibility 40 % 60 % 20 % 30 % 50 % 70 %30 30 % % 70 % / / climate other human the western route change (%) activities (%) project (%) Influence of Influence of Influence of 0.2 % 5.0 % 3.5 % 1.5 % − ected by the project. ff (percentage of area) − − + + − − + − ect Influence degeree Influence type ff + − + + + 2 % 8 % 0.010 % 0.005 % 0.020 % + + − ) patches (%) geneity tivity tivity 2 9.04.3 0.02 % 20.2 11.5 10490 10489 − − Integral Local Percentage Positive influence influence or negative +− +− − ++ − − + + − − − ected by Influence range Influence e ff 0.005 0.001 0.010 0.020 20 %10 % No Yes They are located at upstream water sources area, not a − + + + overland flow concentration via river Wetlands with water charging via Wetlands with water charging ) patches (%) geneity tivity tivity (km 70 %30 % No They are not within the influence range of the water resource area, therefore not a 2 6.5 3.2 60.8 26.7 − + Area Number of Hetero- Connec- Produc- Area Number of Hetero- Connec- Produc- (km + − sources (percentage of area) Wetland landscape pattern evolution tendency and its influence factors. Comprehensive evaluation of the influence of the western route project on wetlands. route project 1980–2000 2000–2009 Without the western route project With the western according to their the project Situation Wetlands classified Area a Water recharge Water recharging via river via overland flow concentration value) Before current year Current year to 2030 (estimate Table 5. Table 4. Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | -N Water quality 3 erent situations and ff NH Mn BOD 5 10492 10491 201043 km below the county79 town km in below 2020 the countyThe town county in town 2020 in 203079 km – below the county town in – 20302010 – – –43 km below the county79 town km – in – – below 2020 the countyThe town county in – town 2020 in 203079 km I below I the county town – in – I 2030 IV II III I II – II IV III II II II II I V II II II II II II II II II II II Comprehensive evaluation concerning the influence of the western route project on Water environment quality evaluation of Ake River reach under di Situation Index of water quality BOD No water transfer In three target yearsWater transfer Upper stream in 2020 and 2030No water transfer In three I target years IWater transfer Upper II stream II in 2020 and 2030 II II I I II II II II II II II II

erent years. olto control pollution

ff control pollution

With Without Way of influence SubjectInundation of influenceWater transferSpecies Ecosystem Bushes of the natural reserves below the dam site Weak Biodiversity Level of influence Serious Weak in di Table 7. Table 6. natural reserves. Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Influence below Zhuanda Dam site significantly by 20 %–30 % 20 % in April, May and June when fish lay eggs 10494 10493 ected factors Influence degree ff TemperatureRainfallSalix atopantha Water depth at cross-sections Little influence Manzetang wetland and the DugoulaRangtang area County of MonthlyOther average wetlands water Annual depth average decreases rainfall is increased by 22 mm No influence Influence of the western route project on typical landscape ecology and environment Arrangement diagram of the project. Local climateand vegetation Wind speed Humidity fieldTypical rivercorridors Average flow speed at cross-sectionsTypical wetlands River width at cross-sectionsNatural reserves Wetland Decrease landscape larger pattern in index flood Little season influence Significant than at normal the Natural season location reserves of such 2 as m Yanboyeze wetland, Little influence Water environmentbelow Monthly Eutrophication the average at river dam the width site Little water is influence transfer reduced reservoir by about Environment capacity Minor possibility Reduced, but with little influence on water quality of river Eco-environmentof Typical landscape A Fig. 1. Table 8. factors at the water resource area. Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | 10496 10495 The evaluation scope. Main considerations of the evaluation. Fig. 3. Fig. 2. Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper |

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25 15 20 10 5 15 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | 10500 10499 Influence of the project on the ecology and environment of the water resource area (2). Influence of the project on the ecology and environment of the water resource area (1). Fig. 7. Fig. 6.