Volume 17,Issue 1,2019 Table of Contents
2019, 17(1):1-7.
Abstract:
In or der t o assess the risk of r egional droug ht disaster r easo nably, w e too k the monthly precipitatio n data of 14 mete2 o ro log ical stat ions in Minjiang Riv er Basin fr om 1961 to 2012 as the r esear ch o bject, and, with thr esho ld as a variable, set thr ee cutting lev els acco rding to the t heo ry o f runs to identify dro ug ht events. Then w e used the best fit Co pula function t o co nstr uct the joint distribution of droug ht durat ion and severity and analy zed the pr obabilistic char acteristics and r et ur n perio d. The re2 sults show ed that Gumbel Co pula funct ion demonstrated the best fitness for M injiang River Basin. Aft er the analy sis of the spa2 tial distribution of conditional pr obability P( S [ 60 mm| D \3 mo nths) , t he results indicat ed that the pro babilit y of occurrence on t he three cut ting lev els increased from the southeast to the northwest of the basin. T he r esults o f joint r et ur n period demon2 str ated that the dr ought in the no rtheaster n and southern parts o f the basin w as mo re serious than that in the central and w estern re2 g ions, while the results of co2occurrence retur n period showed that the drought in the west of the basin was more serio us than that in the east. The spatial dist ribution cha racterist ics o f joint r eturn period wer e mo re stable than tho se o f co2occurrence r eturn peri2 o d. The jo int return perio ds of the w ho le basin on each cut ting level wer e r elativ ely clo se. This study could pr ovide a basis for sett ing the cutting lev el o f the theor y o f runs, cho osing o pt imal Co pula funct ion, and co nduct ing multivariate dr ought analy sis.
In or der t o assess the risk of r egional droug ht disaster r easo nably, w e too k the monthly precipitatio n data of 14 mete2 o ro log ical stat ions in Minjiang Riv er Basin fr om 1961 to 2012 as the r esear ch o bject, and, with thr esho ld as a variable, set thr ee cutting lev els acco rding to the t heo ry o f runs to identify dro ug ht events. Then w e used the best fit Co pula function t o co nstr uct the joint distribution of droug ht durat ion and severity and analy zed the pr obabilistic char acteristics and r et ur n perio d. The re2 sults show ed that Gumbel Co pula funct ion demonstrated the best fitness for M injiang River Basin. Aft er the analy sis of the spa2 tial distribution of conditional pr obability P( S [ 60 mm| D \3 mo nths) , t he results indicat ed that the pro babilit y of occurrence on t he three cut ting lev els increased from the southeast to the northwest of the basin. T he r esults o f joint r et ur n period demon2 str ated that the dr ought in the no rtheaster n and southern parts o f the basin w as mo re serious than that in the central and w estern re2 g ions, while the results of co2occurrence retur n period showed that the drought in the west of the basin was more serio us than that in the east. The spatial dist ribution cha racterist ics o f joint r eturn period wer e mo re stable than tho se o f co2occurrence r eturn peri2 o d. The jo int return perio ds of the w ho le basin on each cut ting level wer e r elativ ely clo se. This study could pr ovide a basis for sett ing the cutting lev el o f the theor y o f runs, cho osing o pt imal Co pula funct ion, and co nduct ing multivariate dr ought analy sis.
2019, 17(1):8-14.
Abstract:
A lar ge2scale affo restation pro ject has been implement ed in the Lo ess Plateau since 1999, but w hether the pro ject has intensified r egional water supply pr essure is being w idely debated. In o rder to scientifically analyze the w ater cycle process in the Lo ess Plateau, this study calculated the evapot ranspir atio n changes of t he Jing he Riv er basin based on the Choudhury2Yang e2 quation during 2000 to 2014, and quant itativ ely dist ing uished the co nt ributio n o f climatic facto rs and that o f underlying surface facto rs to ev apo transpiratio n chang es. Results show ed that: since the implementat ion o f the afforestation pro ject, the ev apo trans2 pir atio n o f the Jing he River basin has slig ht ly declined at an annual averag e rate of - 21 28 mm. Precipit ation was the dominant facto r o f ev apo transpiratio n chang es in the study period, w ith an averag e co ntribution rate of 761 8% , w hich was far g reater than the contribut ion of potential evapotr anspir ation chang e ( 401 8% ) and underly ing surface change ( - 171 5% ) . This st udy show s that the Choudhury2Yang equatio n has impo rtant scientif ic sig nificance fo r quantitativ ely distinguishing the effects of climat e and underlying surf ace chang es on ev apo transpirat ion.
A lar ge2scale affo restation pro ject has been implement ed in the Lo ess Plateau since 1999, but w hether the pro ject has intensified r egional water supply pr essure is being w idely debated. In o rder to scientifically analyze the w ater cycle process in the Lo ess Plateau, this study calculated the evapot ranspir atio n changes of t he Jing he Riv er basin based on the Choudhury2Yang e2 quation during 2000 to 2014, and quant itativ ely dist ing uished the co nt ributio n o f climatic facto rs and that o f underlying surface facto rs to ev apo transpiratio n chang es. Results show ed that: since the implementat ion o f the afforestation pro ject, the ev apo trans2 pir atio n o f the Jing he River basin has slig ht ly declined at an annual averag e rate of - 21 28 mm. Precipit ation was the dominant facto r o f ev apo transpiratio n chang es in the study period, w ith an averag e co ntribution rate of 761 8% , w hich was far g reater than the contribut ion of potential evapotr anspir ation chang e ( 401 8% ) and underly ing surface change ( - 171 5% ) . This st udy show s that the Choudhury2Yang equatio n has impo rtant scientif ic sig nificance fo r quantitativ ely distinguishing the effects of climat e and underlying surf ace chang es on ev apo transpirat ion.
2019, 17(1):15-19.
Abstract:
Coupling ensemble pr ecipitatio n predictio n w ith hydro lo gical mo dels is an impo rtant develo pment direction o f hydro2 log ical fo recasting. Howev er, due to the uncertaint y of the initial atmo spheric conditions and model physics, numerical pr ecipita2 tion for ecasts inevitably hav e errors. In this study , based on GFS ensemble precipitation r efor ecasts with a 1282day lead time, w e analyzed five statistical po st2pr ocessing models that wer e developed based on extended log istic reg ressio n ( ELR) and heterosce2 dastic ext ended lo gistic r egr essio n ( H ELR) alg orithms, and compared t heir co rr ect ion effects on the GFS ensemble precipitatio n forecasts in Xix ian sub2basin of H uai river basin. T he r esults indicated that these five models all made significant impro vements to the GFS raw for ecast; but w ith the ex tensio n o f t he lead time, their correction effects tended to attenuate. In g ener al, the tw o HELR2based models had better perfo rmance compar ed to the other thr ee ELR2based models.
Coupling ensemble pr ecipitatio n predictio n w ith hydro lo gical mo dels is an impo rtant develo pment direction o f hydro2 log ical fo recasting. Howev er, due to the uncertaint y of the initial atmo spheric conditions and model physics, numerical pr ecipita2 tion for ecasts inevitably hav e errors. In this study , based on GFS ensemble precipitation r efor ecasts with a 1282day lead time, w e analyzed five statistical po st2pr ocessing models that wer e developed based on extended log istic reg ressio n ( ELR) and heterosce2 dastic ext ended lo gistic r egr essio n ( H ELR) alg orithms, and compared t heir co rr ect ion effects on the GFS ensemble precipitatio n forecasts in Xix ian sub2basin of H uai river basin. T he r esults indicated that these five models all made significant impro vements to the GFS raw for ecast; but w ith the ex tensio n o f t he lead time, their correction effects tended to attenuate. In g ener al, the tw o HELR2based models had better perfo rmance compar ed to the other thr ee ELR2based models.
2019, 17(1):20-25.
Abstract:
In order to explore the w ater r eso ur ces security ( WRS) pr oblem in H uaihe Riv er Basin, w e est ablished the w ater re2 sour ces security evaluation index sy stem of the H uaihe River Basin. Using the mult i2criteria decisio n2making method2ELECTRE III, w e evaluated the water resour ces securit y o f four prov inces in the H uaihe Riv er Basin ( Jiangsu, Anhui, Shando ng and Henan) fr om 2006 to 2012 and r anked them by net co nfidence scor e. The results show ed that: ( 1) Amo ng these pr ovinces, Jian2 g su Pro vince had the best WRS situation, followed by Anhui Pro vince and H enan Pro vince, while Shandong Prov ince had the wo rst. ( 2) Thr oughout the years, the WRS sit uation in Huaihe River Basin w as the best in 2011, w ith the highest scor e reaching 7. 62 and the lowest - 0. 82, all at the near2crisis level; the situatio n w as the w o rst in 2006, w ith the hig hest sco re reaching - 21 03 and the low est - 18. 37, a ll at the crisis lev el ex cept fo r Jiang su Pro vince. ( 3) For o ne pr ovince thr oughout the y ears, wit h the chang e of time, the w ater resources security o f the fo ur pr ovinces all showed an M2shaped trend of first increasing , then decreasing , and then increasing and decr easing ag ain. T his method and ev aluatio n index system hav e str ong applicability and can pr ov ide relatively objective evaluation results. T hey pr esent a new perspect ive and a new method for w ater resour ces security e2 v aluatio n in the Huaihe River Basin. The pro per quantitat ive and t rend analysis of WRS will pro vide a scientific basis fo r reasonable development and sustainable ut ilization of w ater r eso ur ces in the H uaihe River Basin.
In order to explore the w ater r eso ur ces security ( WRS) pr oblem in H uaihe Riv er Basin, w e est ablished the w ater re2 sour ces security evaluation index sy stem of the H uaihe River Basin. Using the mult i2criteria decisio n2making method2ELECTRE III, w e evaluated the water resour ces securit y o f four prov inces in the H uaihe Riv er Basin ( Jiangsu, Anhui, Shando ng and Henan) fr om 2006 to 2012 and r anked them by net co nfidence scor e. The results show ed that: ( 1) Amo ng these pr ovinces, Jian2 g su Pro vince had the best WRS situation, followed by Anhui Pro vince and H enan Pro vince, while Shandong Prov ince had the wo rst. ( 2) Thr oughout the years, the WRS sit uation in Huaihe River Basin w as the best in 2011, w ith the highest scor e reaching 7. 62 and the lowest - 0. 82, all at the near2crisis level; the situatio n w as the w o rst in 2006, w ith the hig hest sco re reaching - 21 03 and the low est - 18. 37, a ll at the crisis lev el ex cept fo r Jiang su Pro vince. ( 3) For o ne pr ovince thr oughout the y ears, wit h the chang e of time, the w ater resources security o f the fo ur pr ovinces all showed an M2shaped trend of first increasing , then decreasing , and then increasing and decr easing ag ain. T his method and ev aluatio n index system hav e str ong applicability and can pr ov ide relatively objective evaluation results. T hey pr esent a new perspect ive and a new method for w ater resour ces security e2 v aluatio n in the Huaihe River Basin. The pro per quantitat ive and t rend analysis of WRS will pro vide a scientific basis fo r reasonable development and sustainable ut ilization of w ater r eso ur ces in the H uaihe River Basin.
2019, 17(1):26-38.
Abstract:
In a chang ing env ir onment, wetland hydrolog ical connectivit y decreases significantly, r esulting in the shrinkag e o f w et2 land area and the degr adat ion of eco2hydro lo gical functio ns o f wetlands, and wo rse still, the deterio ration of water envir onment and the incr eased risk o f flo ods and dr oughts in the river basin. On the basis o f defining the connotation and characteristics of wetland hydro lo gical co nnectivity, this article systematically summarizes t he research histo ry o f w etland hydr olo gica l co nnectiv i2 ty . It can be div ided int o the g erminatio n stag e ( from 1980 to 2009) and the ex plo ratio n stag e ( from 2010 to present) . T hen the article focuses on the r esear ch hotspots and pro gr ess of w etland hy dr olog ical connectivity , including quantitative assessment met ho ds for wet land hydro log ical connect ivity, the functio ns of wet land hydro log ical co nnectivity, the applicatio ns of w etland hy dr olog ical connect ivity in w etland pro tect ion and r est orat ion and basin w ater management. Fina lly, in view of the pro blems and weaknesses in the current studies of w et land hydro lo gical co nnectiv ity, co nsidering the major natio na l needs fo r w etland pr otectio n and r esto ration and inter co nnected river system netw or k in the new perio d, this article pro po ses the key directio ns for future r esear ch.
In a chang ing env ir onment, wetland hydrolog ical connectivit y decreases significantly, r esulting in the shrinkag e o f w et2 land area and the degr adat ion of eco2hydro lo gical functio ns o f wetlands, and wo rse still, the deterio ration of water envir onment and the incr eased risk o f flo ods and dr oughts in the river basin. On the basis o f defining the connotation and characteristics of wetland hydro lo gical co nnectivity, this article systematically summarizes t he research histo ry o f w etland hydr olo gica l co nnectiv i2 ty . It can be div ided int o the g erminatio n stag e ( from 1980 to 2009) and the ex plo ratio n stag e ( from 2010 to present) . T hen the article focuses on the r esear ch hotspots and pro gr ess of w etland hy dr olog ical connectivity , including quantitative assessment met ho ds for wet land hydro log ical connect ivity, the functio ns of wet land hydro log ical co nnectivity, the applicatio ns of w etland hy dr olog ical connect ivity in w etland pro tect ion and r est orat ion and basin w ater management. Fina lly, in view of the pro blems and weaknesses in the current studies of w et land hydro lo gical co nnectiv ity, co nsidering the major natio na l needs fo r w etland pr otectio n and r esto ration and inter co nnected river system netw or k in the new perio d, this article pro po ses the key directio ns for future r esear ch.
2019, 17(1):39-45.
Abstract:
Urban water cycle healt h assessment research has pr actical g uiding sig nificance for ur ban planning, develo pment and co nstr uction, and urban r eso ur ce management. Taking Xican as a study case, based on the conno tatio n of ur ban water cy cle and the key at tributes of water r eso urces, f rom the fo ur dimensions o f w ater ecolo gica l level, wat er resources abundance, w ater qualit y, and water resources utilizatio n, w e built a health assessment sy stem o f w ater cycle based o n key performance index ( KPI) w ith 16 indicato rs, and assessed the health status of w ater cycle of the city from 2010 to 2015. T he results showed t hat the w ater cy cle in Xi'an from 2010 to 2015 was in a sub- healt h state, and the health assessment score w as 31 05231 46 points. The health sco res in 201022011 showed a dow nwar d tr end. In 2011, the healt h scor e w as 31 05 points and was the low est. Af2 terwar ds fr om 2011 to 2015, the health scor e incr eased year by y ear, wit h a sig nificant upwar d tr end. T he drinking w ater so ur ce had the hig hest scor e in water quality com pliance rate, and it w as in a very healt hy state from 2010 to 2015. The per ca2 pita w ater resources and the per unit area water r esources had the w orst scores. From 2010 to 2015, they wer e all serio usly un2 healt hy . Enhancing t he r ationality of wat er resour ces utilizat ion and alleviat ing the co nt radictio n between water supply and demand w ere the key to improv ing t he health status of Xican w ater cycle
Urban water cycle healt h assessment research has pr actical g uiding sig nificance for ur ban planning, develo pment and co nstr uction, and urban r eso ur ce management. Taking Xican as a study case, based on the conno tatio n of ur ban water cy cle and the key at tributes of water r eso urces, f rom the fo ur dimensions o f w ater ecolo gica l level, wat er resources abundance, w ater qualit y, and water resources utilizatio n, w e built a health assessment sy stem o f w ater cycle based o n key performance index ( KPI) w ith 16 indicato rs, and assessed the health status of w ater cycle of the city from 2010 to 2015. T he results showed t hat the w ater cy cle in Xi'an from 2010 to 2015 was in a sub- healt h state, and the health assessment score w as 31 05231 46 points. The health sco res in 201022011 showed a dow nwar d tr end. In 2011, the healt h scor e w as 31 05 points and was the low est. Af2 terwar ds fr om 2011 to 2015, the health scor e incr eased year by y ear, wit h a sig nificant upwar d tr end. T he drinking w ater so ur ce had the hig hest scor e in water quality com pliance rate, and it w as in a very healt hy state from 2010 to 2015. The per ca2 pita w ater resources and the per unit area water r esources had the w orst scores. From 2010 to 2015, they wer e all serio usly un2 healt hy . Enhancing t he r ationality of wat er resour ces utilizat ion and alleviat ing the co nt radictio n between water supply and demand w ere the key to improv ing t he health status of Xican w ater cycle
2019, 17(1):46-53.
Abstract:
Based on the meteo rolog ical data of 25 met eo ro lo gical stat ions in Guangx i fr om 1958 to 2016, w e ado pted Daniel trend test method, Lee2H eg hinan test, Morlet wav elet analy sis, R/ S analysis, and Kriging interpolation to analy ze the spatial and tem2 por al v ariat ions of the sunshine duratio n, w ind speed, precipit ation, relat ive hum idity, and temperature data in Guang xi. T he re2 sults show ed that in the past 59 years, the annual sunshine duration, annual av erag e w ind speed, and annual av erag e r elativ e hu2 midit y show ed a decr easing tr end; the annual precipitation and annual aver age t em perat ur e show ed a slight rising tr end; these facto rs r espectively had abr upt chang es in 1979, 1974, 2011, 2002 and 1997; they all show ed the complex char act eristic o f multi - time sca le coupling, and their first main periods w ere 22 a, 29 a, 31 a, 26 a and 13 a, respectiv ely ; the H urst indexes o f these met eo ro lo gical fact ors w ere all g reater than 01 5, indicating that the futur e tr end w ill still be consistent w ith the past tr end. In space, the annual sunshine durat ion in Guangx i declined fr om the northwest to the so utheast, wher eas the annual aver age w ind speed, annual precipitat ion, annual aver age relativ e humidity , and annual aver age temper at ur e showed a rising tr end from north to south.
Based on the meteo rolog ical data of 25 met eo ro lo gical stat ions in Guangx i fr om 1958 to 2016, w e ado pted Daniel trend test method, Lee2H eg hinan test, Morlet wav elet analy sis, R/ S analysis, and Kriging interpolation to analy ze the spatial and tem2 por al v ariat ions of the sunshine duratio n, w ind speed, precipit ation, relat ive hum idity, and temperature data in Guang xi. T he re2 sults show ed that in the past 59 years, the annual sunshine duration, annual av erag e w ind speed, and annual av erag e r elativ e hu2 midit y show ed a decr easing tr end; the annual precipitation and annual aver age t em perat ur e show ed a slight rising tr end; these facto rs r espectively had abr upt chang es in 1979, 1974, 2011, 2002 and 1997; they all show ed the complex char act eristic o f multi - time sca le coupling, and their first main periods w ere 22 a, 29 a, 31 a, 26 a and 13 a, respectiv ely ; the H urst indexes o f these met eo ro lo gical fact ors w ere all g reater than 01 5, indicating that the futur e tr end w ill still be consistent w ith the past tr end. In space, the annual sunshine durat ion in Guangx i declined fr om the northwest to the so utheast, wher eas the annual aver age w ind speed, annual precipitat ion, annual aver age relativ e humidity , and annual aver age temper at ur e showed a rising tr end from north to south.
2019, 17(1):54-60.
Abstract:
With the develo pment of so cial eco nomy, the w ater resources pro blem in Henan Prov ince is becoming incr easing ly seri2 o us. We selected 13 eva luation indexes to constr uct an evaluat ion index system for w ater resources carr ying capacit y in Henan Pro vince, and w e used the principal component ana lysis method to evaluat e the w ater resources carry ing ca pacity in Henan Prov2 ince in both tempo ral and spat ial dimensions. T he results show ed that : ( 1) The tempor al v ariation characteristics o f w ater re2 sour ces carr ying capacit y in H enan Pro vince w ere ma inly related to the lev el of so cial and eco nomic develo pment, the level of water supply and demand, and the intensity of human act ivities. T he water reso ur ces carry ing capacity in H enan Prov ince show ed a fluctuat ing increasing tr end fr om 2007 to 2016. ( 2) The spatial distribution characteristics o f w ater resour ces ca rr ying capacity in Henan Pr ovince w er e mainly related to the level o f socia l and econom ic develo pment, the status of ag ricultur al devel2 o pment, and the nat ur al endow ment o f water resources in differ ent cities. Zheng zhou City had the hig hest level o f water re2 sour ces carr ying ca pacity , w hile Luohe City, Hebi Cit y, and Jiyuan Cit y had the low est level. This study can pr ovide a scientific basis fo r the sustainable utilizatio n of water r eso urces in H enan Pr ovince and the formulatio n of related rational manag ement po licies.
With the develo pment of so cial eco nomy, the w ater resources pro blem in Henan Prov ince is becoming incr easing ly seri2 o us. We selected 13 eva luation indexes to constr uct an evaluat ion index system for w ater resources carr ying capacit y in Henan Pro vince, and w e used the principal component ana lysis method to evaluat e the w ater resources carry ing ca pacity in Henan Prov2 ince in both tempo ral and spat ial dimensions. T he results show ed that : ( 1) The tempor al v ariation characteristics o f w ater re2 sour ces carr ying capacit y in H enan Pro vince w ere ma inly related to the lev el of so cial and eco nomic develo pment, the level of water supply and demand, and the intensity of human act ivities. T he water reso ur ces carry ing capacity in H enan Prov ince show ed a fluctuat ing increasing tr end fr om 2007 to 2016. ( 2) The spatial distribution characteristics o f w ater resour ces ca rr ying capacity in Henan Pr ovince w er e mainly related to the level o f socia l and econom ic develo pment, the status of ag ricultur al devel2 o pment, and the nat ur al endow ment o f water resources in differ ent cities. Zheng zhou City had the hig hest level o f water re2 sour ces carr ying ca pacity , w hile Luohe City, Hebi Cit y, and Jiyuan Cit y had the low est level. This study can pr ovide a scientific basis fo r the sustainable utilizatio n of water r eso urces in H enan Pr ovince and the formulatio n of related rational manag ement po licies.
2019, 17(1):61-69.
Abstract:
During the flooding o f simulated rivers, the same2frequency rainsto rm combination scenario of the ma in str eam and tributary cannot r easo nably reflect the real o verflow situat ion. In view of this defect, considering the difference of actua l pr ecipi2 tat ion conditions bet ween the main stream and tributar y during the flo oding , w e est ablished a MikeFlood coupled hydro dy namic model based on floo ding scenario s of different fr equency combinatio ns of t he main str eam and tributar y. I n this paper, the typical hilly landform area, Xiushui, was taken as the research object. We simulated the 24 combinations in w hich the main stream and the main tributaries r espectively had 202, 502 and 1002year r ainstorms. We compar ed several scenario s w ith the ty pical st orm scenario s in which the ma in str eam and tribut aries had rainsto rms o f the same frequency. The compariso n results show ed t hat the selected combination scenarios pr esented much different distribution and size o f submer ged dept h than the t ypical scenarios. They can div ersely reflect the o verflow situation in the flood, pro viding
During the flooding o f simulated rivers, the same2frequency rainsto rm combination scenario of the ma in str eam and tributary cannot r easo nably reflect the real o verflow situat ion. In view of this defect, considering the difference of actua l pr ecipi2 tat ion conditions bet ween the main stream and tributar y during the flo oding , w e est ablished a MikeFlood coupled hydro dy namic model based on floo ding scenario s of different fr equency combinatio ns of t he main str eam and tributar y. I n this paper, the typical hilly landform area, Xiushui, was taken as the research object. We simulated the 24 combinations in w hich the main stream and the main tributaries r espectively had 202, 502 and 1002year r ainstorms. We compar ed several scenario s w ith the ty pical st orm scenario s in which the ma in str eam and tribut aries had rainsto rms o f the same frequency. The compariso n results show ed t hat the selected combination scenarios pr esented much different distribution and size o f submer ged dept h than the t ypical scenarios. They can div ersely reflect the o verflow situation in the flood, pro viding
2019, 17(1):70-75.
Abstract:
In this study, we used t he labor ator y simulation method to investig ate the changes of the phy sical and chemical pro per2 ties o f bot tom sediment and the overly ing wat er qualit y as a function of the dosage of self2made bio2chemical compounding ag ent ( w ith "denitrifying bacteria2calcium nitrate" as the main raw material) in the in2 situ biochemical remediation o f black2odor sedi2 ment. Based on comprehensive consider atio n, we determined t hat t he o ptimal and cost2saving do sag e of treatment ag ent for the remov al o f black2o do r pollutants should be 2 000 mg / L ( calculated as calcium nitr ate2N) . After bury ing the sediment tr eatment agent in the test sediment fo r 30 day s, w e fo und the T P of the ov erlying w ater ( 400 ml) w as r educed fr om 01 50 mg/ L to 01 36 mg/ L; CODCr , ammonia nitr og en, nitr ate nitr og en, and nitrite nitr og en respect ively increased from 31 mg/ L, 01 10 mg/ L, 01 65 mg/ L, and 01 07 mg / L to 325 mg / L, 301 27 mg / L, 41 91 mg/ L, and 131 55 mg/ L; the sediment AVS w as r educed from 11 31 Lmo l/ g t o 01 35 Lmol/ g ; the sediment looked loo se and ex panded, and tur ned from black to yellow . We judged that this dosag e wo rked w ell on the treatment of black2odor sediment. It can be used as the basis fo r furt her pilo t st udy o n the in2situ remedia2 tion of black2odor sediment in a river co urse in Binhai New Area o f Tianjin, in or der to determine the optimal dosag e.
In this study, we used t he labor ator y simulation method to investig ate the changes of the phy sical and chemical pro per2 ties o f bot tom sediment and the overly ing wat er qualit y as a function of the dosage of self2made bio2chemical compounding ag ent ( w ith "denitrifying bacteria2calcium nitrate" as the main raw material) in the in2 situ biochemical remediation o f black2odor sedi2 ment. Based on comprehensive consider atio n, we determined t hat t he o ptimal and cost2saving do sag e of treatment ag ent for the remov al o f black2o do r pollutants should be 2 000 mg / L ( calculated as calcium nitr ate2N) . After bury ing the sediment tr eatment agent in the test sediment fo r 30 day s, w e fo und the T P of the ov erlying w ater ( 400 ml) w as r educed fr om 01 50 mg/ L to 01 36 mg/ L; CODCr , ammonia nitr og en, nitr ate nitr og en, and nitrite nitr og en respect ively increased from 31 mg/ L, 01 10 mg/ L, 01 65 mg/ L, and 01 07 mg / L to 325 mg / L, 301 27 mg / L, 41 91 mg/ L, and 131 55 mg/ L; the sediment AVS w as r educed from 11 31 Lmo l/ g t o 01 35 Lmol/ g ; the sediment looked loo se and ex panded, and tur ned from black to yellow . We judged that this dosag e wo rked w ell on the treatment of black2odor sediment. It can be used as the basis fo r furt her pilo t st udy o n the in2situ remedia2 tion of black2odor sediment in a river co urse in Binhai New Area o f Tianjin, in or der to determine the optimal dosag e.
2019, 17(1):76-83.
Abstract:
Taking Yong ding Riv er ( Beijing sectio n) as the research object, we monito red the chang es of wat er qualit y in land2 scape w ater bodies w ith different ratios of reclaimed w ater for 24 co nsecutive day s. The monito ring indicato rs included chemical ox yg en demand, ammo nia nitr og en, dissolved o xy gen, pH, co nductivity , and soil micro bial diversity. The r esults show ed that: The micr obial diversity in t he upstream riparian soil of the Yo ngding Riv er is sig nificantly better than that in the dow nstr eam ri2 parian so il. The sand formed by the combination of the two is conducive to enriching so il micr obial diversity. T he wat er body wit h a high ratio o f r eclaimed w ater is mor e sensitive to envir onmental changes. Its w ater qualit y is mo re prone t o changes when influenced by exter nal factors, and deterior at es fast er at high temper atur e. Accor ding to the com pr ehensive analysis of v arious water qualit y indicators monito red by the ex periment , the w ater quality of impounded landsca pe water bodies will deteriorat e co nt inuously if t he ratio of reclaimed water ex ceeds 75% . It is recommended that the r atio of reclaimed w ater in Yongding River be contr olled below 75% .
Taking Yong ding Riv er ( Beijing sectio n) as the research object, we monito red the chang es of wat er qualit y in land2 scape w ater bodies w ith different ratios of reclaimed w ater for 24 co nsecutive day s. The monito ring indicato rs included chemical ox yg en demand, ammo nia nitr og en, dissolved o xy gen, pH, co nductivity , and soil micro bial diversity. The r esults show ed that: The micr obial diversity in t he upstream riparian soil of the Yo ngding Riv er is sig nificantly better than that in the dow nstr eam ri2 parian so il. The sand formed by the combination of the two is conducive to enriching so il micr obial diversity. T he wat er body wit h a high ratio o f r eclaimed w ater is mor e sensitive to envir onmental changes. Its w ater qualit y is mo re prone t o changes when influenced by exter nal factors, and deterior at es fast er at high temper atur e. Accor ding to the com pr ehensive analysis of v arious water qualit y indicators monito red by the ex periment , the w ater quality of impounded landsca pe water bodies will deteriorat e co nt inuously if t he ratio of reclaimed water ex ceeds 75% . It is recommended that the r atio of reclaimed w ater in Yongding River be contr olled below 75% .
2019, 17(1):84-91.
Abstract:
Water env ir onment capacity ( WEC) refers to the max imum amount of po llutants that can be assimilated by a w ater bo dy g iven the co ndition that the w at er enviro nment o f the water function ar ea meets the qualit y standards. The precise determi2 natio n o f WEC has important pr act ical sig nificance for the ratio nal exploitation and effect ive prot ection of wat er resour ces. Wa2 ter conserv ancy pro jects and human activities have changed the o rig inal hydro lo gical sit uation of the river to v ary ing deg rees, and the precise verificat ion of the wat er envir onment capacity under the inf luence of chang es in hy dr olog ical situatio n has gr adually become a pro blem that ur gently needs study and so lutio n. We to ok the H uang bo Riv er in Yang tze River Basin as a case study,select ed three majo r influencing facto rs, including the converg ent tributaries, reserv oirs, and w ater diversion pro jects, and ana2 lyzed their im pacts on the hy dr olog ical situation of the river and on the w ater envir onment capacit y. We put fo rw ard some corre2 sponding parameter determination metho ds, and calculated the w ater environment capacity based on the one2dimensio na l w ater qualit y mathematical mo del. Finally, taking the typical section o f East Br anch Reser ve of the H uang bo Riv er as a case study, w e compar ed the WEC r esults o f the pro po sed method and the tr adit ional metho d. T he results show ed that the pr oposed method wit h co nsideration to the impact o f chang es in hydrolog ical situatio n can contribute to the accurate verificatio n of the w ater env i2 r onment capacity t o a certain ex tent. The research results can pro vide certain technical references for reg io nal effective pr otec2 tion of w ater r eso ur ces, preventio n o f water po llut ion, and improv ement o f water env iro nment.
Water env ir onment capacity ( WEC) refers to the max imum amount of po llutants that can be assimilated by a w ater bo dy g iven the co ndition that the w at er enviro nment o f the water function ar ea meets the qualit y standards. The precise determi2 natio n o f WEC has important pr act ical sig nificance for the ratio nal exploitation and effect ive prot ection of wat er resour ces. Wa2 ter conserv ancy pro jects and human activities have changed the o rig inal hydro lo gical sit uation of the river to v ary ing deg rees, and the precise verificat ion of the wat er envir onment capacity under the inf luence of chang es in hy dr olog ical situatio n has gr adually become a pro blem that ur gently needs study and so lutio n. We to ok the H uang bo Riv er in Yang tze River Basin as a case study,select ed three majo r influencing facto rs, including the converg ent tributaries, reserv oirs, and w ater diversion pro jects, and ana2 lyzed their im pacts on the hy dr olog ical situation of the river and on the w ater envir onment capacit y. We put fo rw ard some corre2 sponding parameter determination metho ds, and calculated the w ater environment capacity based on the one2dimensio na l w ater qualit y mathematical mo del. Finally, taking the typical section o f East Br anch Reser ve of the H uang bo Riv er as a case study, w e compar ed the WEC r esults o f the pro po sed method and the tr adit ional metho d. T he results show ed that the pr oposed method wit h co nsideration to the impact o f chang es in hydrolog ical situatio n can contribute to the accurate verificatio n of the w ater env i2 r onment capacity t o a certain ex tent. The research results can pro vide certain technical references for reg io nal effective pr otec2 tion of w ater r eso ur ces, preventio n o f water po llut ion, and improv ement o f water env iro nment.
2019, 17(1):92-97.
Abstract:
Water quality mo nitoring play s a significant ro le in w ater envir onment impact assessment and water environment man2 ag ement . The current water quality monito ring data hav e the fo llow ing problems: low monit oring frequency , difficult ies in mo ni2 to ring , complex it y of influencing facto rs, and low level o f informatization. T o make up fo r the abo ve disadv antag es, w e used the distribut ed hydro lo gical model to supplement t he w ater quality mo nitoring data and trace the sour ce of pollutants. A case study was conducted in the Jianjiang Riv er basin. We established a SWAT mo del to simulate the tot al pho sphor us po llut ants based o n the hy dr ometeor olog y, the underly ing surface data, and the wat er qua lity data of fo ur sectio ns from 2010 t o 2014. Results indica2 ted that the dist ributed hydro log ical mo del can not only complement the to tal pho sphor us dat a o f the four monito ring sections in the same perio d, but also t race the so ur ce of total phospho rus pollutio n in t his basin to non2po int source po llut ion, and r ev eal the spatial distributio n o f the non2point so ur ce pollution and the pro po rtions of different pollutio n categ ories. Fert ilizer loss is the main po llution source in this basin, particularly in wet y ea rs, in w hich it acco unted for up to 66% o f po llut ion
Water quality mo nitoring play s a significant ro le in w ater envir onment impact assessment and water environment man2 ag ement . The current water quality monito ring data hav e the fo llow ing problems: low monit oring frequency , difficult ies in mo ni2 to ring , complex it y of influencing facto rs, and low level o f informatization. T o make up fo r the abo ve disadv antag es, w e used the distribut ed hydro lo gical model to supplement t he w ater quality mo nitoring data and trace the sour ce of pollutants. A case study was conducted in the Jianjiang Riv er basin. We established a SWAT mo del to simulate the tot al pho sphor us po llut ants based o n the hy dr ometeor olog y, the underly ing surface data, and the wat er qua lity data of fo ur sectio ns from 2010 t o 2014. Results indica2 ted that the dist ributed hydro log ical mo del can not only complement the to tal pho sphor us dat a o f the four monito ring sections in the same perio d, but also t race the so ur ce of total phospho rus pollutio n in t his basin to non2po int source po llut ion, and r ev eal the spatial distributio n o f the non2point so ur ce pollution and the pro po rtions of different pollutio n categ ories. Fert ilizer loss is the main po llution source in this basin, particularly in wet y ea rs, in w hich it acco unted for up to 66% o f po llut ion
2019, 17(1):98-104.
Abstract:
In order to solve the pr oblem of sediment diffusion in dr edg ing pr ojects, we desig ned a cutter suctio n ex periment de2 v ice. The diffusion dist ribution o f sediment was pr edicted by CFD model. CPAM, PSF and CPAM/ PSF w ere added during the cutter suctio n pro cess. We explo red the anti- diffusion effect of anti2diffusion ag ents in cutter suctio n process in terms of the sediment set tling rate, tur bidity o f overly ing w ater, COD, particle size, and SEM mo rpholog y chang es. T he results show ed t hat CPAM had the best effect on preventing sediment diffusio n. When CPAM dosage w as 15 mg/ L, 95% of the mud sam ples basi2 cally sett led in an instant relative to the final sediment settling rat e; after 1 ho ur of sett ling , the turbidity o f the ov erlying w ater reached the low est value o f 101 23 NTU and COD reached the lowest value o f 121 0 mg/ L, w hich w ere respect ively 831 6% and 891 1% low er t han t he turbidity and COD of t he overly ing wat er w itho ut anti2diffusion ag ent. Fr om the SEM pictures o f the sed2 iment samples, it can be seen that t he sediment particle size increased the most obvio usly, with the median particle size reaching 191 250 Lm. which w as 117% higher than that of the sediment w ithout the anti2diffusion agent. T he ag ent showed go od effects in pr event ing the spr ead o f sediment.
In order to solve the pr oblem of sediment diffusion in dr edg ing pr ojects, we desig ned a cutter suctio n ex periment de2 v ice. The diffusion dist ribution o f sediment was pr edicted by CFD model. CPAM, PSF and CPAM/ PSF w ere added during the cutter suctio n pro cess. We explo red the anti- diffusion effect of anti2diffusion ag ents in cutter suctio n process in terms of the sediment set tling rate, tur bidity o f overly ing w ater, COD, particle size, and SEM mo rpholog y chang es. T he results show ed t hat CPAM had the best effect on preventing sediment diffusio n. When CPAM dosage w as 15 mg/ L, 95% of the mud sam ples basi2 cally sett led in an instant relative to the final sediment settling rat e; after 1 ho ur of sett ling , the turbidity o f the ov erlying w ater reached the low est value o f 101 23 NTU and COD reached the lowest value o f 121 0 mg/ L, w hich w ere respect ively 831 6% and 891 1% low er t han t he turbidity and COD of t he overly ing wat er w itho ut anti2diffusion ag ent. Fr om the SEM pictures o f the sed2 iment samples, it can be seen that t he sediment particle size increased the most obvio usly, with the median particle size reaching 191 250 Lm. which w as 117% higher than that of the sediment w ithout the anti2diffusion agent. T he ag ent showed go od effects in pr event ing the spr ead o f sediment.
LIU Jinshan
,
NI Fuquan.
,
DENG Yu
,
LI Linhuan
,
WANG Zhigang
,
ZHOU Dengke
,
NIE Chao
,
ZHANG Yang
,
MA Jie
2019, 17(1):105-112.
Abstract:
Acco rding to the curr ent situation and characteristics o f soil erosio n in t he upper reaches of Minjiang River, after deter2 mining the assessment index es, w e used the metho d o f Weig hted Superposit ion Analysis to ex plor e the ero sion risk. T he r esults are as follow s: ( 1) In t he upper r eaches of Minjiang River, steep slo pes make up 611 20% of the area; annual r ainfa ll v aries sig2 nificantly; the so il is loo se and soft; the impact o f earthquake is stro ng . ( 2) The r atio of moderate and above ero sion risk w as 891 31% in the study ar ea, indicating a serious so il ero sion situat ion. ( 3) T he moderate risk areas a re mainly distributed near the water netw or k, and ar e closely related to land use t ypes and human activit ies; the hig h risk areas ar e mainly distributed in the west, so uthw est and so ut h of the upper reaches of Minjiang River, and are clo sely co nnected w ith the Wenchuan Earthquake. ( 4) Wenchuan County and Lixian County ar e key manag ement r egions of hig h erosion risk, and H eishui County , Maox ian Count y, and Songpan Co unty a re manag ement reg ions of moderate er osion risk.
Acco rding to the curr ent situation and characteristics o f soil erosio n in t he upper reaches of Minjiang River, after deter2 mining the assessment index es, w e used the metho d o f Weig hted Superposit ion Analysis to ex plor e the ero sion risk. T he r esults are as follow s: ( 1) In t he upper r eaches of Minjiang River, steep slo pes make up 611 20% of the area; annual r ainfa ll v aries sig2 nificantly; the so il is loo se and soft; the impact o f earthquake is stro ng . ( 2) The r atio of moderate and above ero sion risk w as 891 31% in the study ar ea, indicating a serious so il ero sion situat ion. ( 3) T he moderate risk areas a re mainly distributed near the water netw or k, and ar e closely related to land use t ypes and human activit ies; the hig h risk areas ar e mainly distributed in the west, so uthw est and so ut h of the upper reaches of Minjiang River, and are clo sely co nnected w ith the Wenchuan Earthquake. ( 4) Wenchuan County and Lixian County ar e key manag ement r egions of hig h erosion risk, and H eishui County , Maox ian Count y, and Songpan Co unty a re manag ement reg ions of moderate er osion risk.
2019, 17(1):113-119.
Abstract:
The dischar ge of ammonium2co nt aining w astewater fr om fertilizer plants may cause g ro undwater contamination. T he adsor pt ion by soil in the vadose zo ne is an important pr ocess t o prevent ammonium from entering the aquifer. We select ed four typical so il samples at differ ent depths in a vadose zo ne, and co nducted batch labor ator y experiments to study the adso rption ki2 netics and iso thermal adsor ption char acteristics of the soils w ith reg ard to ammo nium in wastew ater fr om fertilizer plants. T he ammonium sulfat e solution was prepa red fo r the ex periments. Results show ed that ammonium can be adso rbed easily by v arious so il particles. Some materia ls such as o rg anic matters in the wastew ater can pr olong the adso rptio n equilibrium time, and affect the adsor ption capacity of soils to ammo nium; specifically , they will incr ease the capacity in low2concentr atio n ammo nium so lu2 tion, but their effects in hig h2concent ratio n ammonium so lutio n depend o n the soil or ganic matt er co ntent. Soils w ith differ ent textures have differ ent adso rptio n behav iors. Generally , the adsor ption ca pacity o f co hesiv e so il is better than that of sandy soil. Compar ed w ith the Freund lich and L angmuir iso thermal, BET adsorptio n iso thermal can better f it the ex perimental adso rptio n data. This verifies the feasibility of apply ing BET formula to the study of isotherma l adsor ption of ammonium and indicates t hat the adsor ption of ammonium in soil particles is multi2mo lecular layer adso rption.
The dischar ge of ammonium2co nt aining w astewater fr om fertilizer plants may cause g ro undwater contamination. T he adsor pt ion by soil in the vadose zo ne is an important pr ocess t o prevent ammonium from entering the aquifer. We select ed four typical so il samples at differ ent depths in a vadose zo ne, and co nducted batch labor ator y experiments to study the adso rption ki2 netics and iso thermal adsor ption char acteristics of the soils w ith reg ard to ammo nium in wastew ater fr om fertilizer plants. T he ammonium sulfat e solution was prepa red fo r the ex periments. Results show ed that ammonium can be adso rbed easily by v arious so il particles. Some materia ls such as o rg anic matters in the wastew ater can pr olong the adso rptio n equilibrium time, and affect the adsor ption capacity of soils to ammo nium; specifically , they will incr ease the capacity in low2concentr atio n ammo nium so lu2 tion, but their effects in hig h2concent ratio n ammonium so lutio n depend o n the soil or ganic matt er co ntent. Soils w ith differ ent textures have differ ent adso rptio n behav iors. Generally , the adsor ption ca pacity o f co hesiv e so il is better than that of sandy soil. Compar ed w ith the Freund lich and L angmuir iso thermal, BET adsorptio n iso thermal can better f it the ex perimental adso rptio n data. This verifies the feasibility of apply ing BET formula to the study of isotherma l adsor ption of ammonium and indicates t hat the adsor ption of ammonium in soil particles is multi2mo lecular layer adso rption.
2019, 17(1):120-129.
Abstract:
To learn about the quality of water environment o f Do ng ping Lake in dr y perio d, w e collected hydro gen and ox yg en stable isoto pes samples and analyzed the distributio n of hydro gen and o x yg en isoto pes, deuterium surplus, and eutro phicatio n co nditions in Dongping Lake. We revealed the effect of evapor ation and human factors on w ater quality during dr y period. T he results showed that: ( 1) The sing le2facto r ev aluatio n showed serious eut rophicatio n in Do ng ping Lake during dry period. T he averag e concentr atio ns of COD, TN and TP in Dong ping Lake w ere 161 92 mg / L, 01 80 mg/ L and 01 31 mg / L, respectiv ely . They wer e close to heavy eutr ophicatio n in the dry period. ( 2) The spatial distribut ions of DD and D18O showed a g radual increasing trend from t he southeast to the northw est o f t he lake area, w hile the d value showed an o pposite distribution tr end to that o f DD and D18O. T he d value o f lake wat er is negative between - 41 77 j and - 121 48 j , indicat ing that the eva po ratio n of water is st rong . ( 3) In the dry period,D18O and DD of lake w ater showed a sig nificant correlat ion w ith the COD, pH and EC, w hich re2 flect ed the effect o f evapor ation fr actionatio n o n the content of COD. Howev er, TN and TP had no significant co rr elatio n with DD and D18O iso topic values because the co ntent of T N and TP w as affected by human facto rs.
To learn about the quality of water environment o f Do ng ping Lake in dr y perio d, w e collected hydro gen and ox yg en stable isoto pes samples and analyzed the distributio n of hydro gen and o x yg en isoto pes, deuterium surplus, and eutro phicatio n co nditions in Dongping Lake. We revealed the effect of evapor ation and human factors on w ater quality during dr y period. T he results showed that: ( 1) The sing le2facto r ev aluatio n showed serious eut rophicatio n in Do ng ping Lake during dry period. T he averag e concentr atio ns of COD, TN and TP in Dong ping Lake w ere 161 92 mg / L, 01 80 mg/ L and 01 31 mg / L, respectiv ely . They wer e close to heavy eutr ophicatio n in the dry period. ( 2) The spatial distribut ions of DD and D18O showed a g radual increasing trend from t he southeast to the northw est o f t he lake area, w hile the d value showed an o pposite distribution tr end to that o f DD and D18O. T he d value o f lake wat er is negative between - 41 77 j and - 121 48 j , indicat ing that the eva po ratio n of water is st rong . ( 3) In the dry period,D18O and DD of lake w ater showed a sig nificant correlat ion w ith the COD, pH and EC, w hich re2 flect ed the effect o f evapor ation fr actionatio n o n the content of COD. Howev er, TN and TP had no significant co rr elatio n with DD and D18O iso topic values because the co ntent of T N and TP w as affected by human facto rs.
2019, 17(1):130-137.
Abstract:
Nano2iro n pr oduced by reductio n w ith g reen tea extr act ( GT2NIP) has g ood r emo val efficiency of hexav alent chromi2 um in w ater. It is ex pected that the remov al of hexav alent chr omium from gr oundw ater can be achieved in situ by injecting GT2 NIP into the aquifer; but this has not been verified yet. In this paper, we pr epar ed nano- ir on by reductio n w ith g reen tea ex2 tr act, measured its reductio n effect o n hex av alent chromium in w ater, and then used sand co lumn to study its remo val efficiency on hex avalent chromium in simulated g ro undw ater. The GT2NIP w e made w ere spherical and unifo rm in size, w ith a diameter of 10220 nm and g ood dispersion stability in w ater. They consisted o f 551 6% Fe2+ and 441 4% Fe3+ . When GT2NIP concent ratio n was 120 g/ L, after 1 h of r eact ion, the remo val rate of Cr( VI) w it h an initial concent ratio n o f 100 mg / L reached 9628% . In the co lumn test, GT2NIP could pass thro ug h the sand column, with an aver age outflow per centage o f 681 6% . When a Cr( ? ) so lu2 tion of 100 mg/ L was injected into t he sand co lumn, the concentrat ion of Cr 3+ w as abo ut 01 20 mg / L, and the concentr ation of Cr 6+ in the effluent was 01 10201 25 mg / L; that is, the to tal remo val r ate o f hex avalent chromium by GT2 NIP w as more than 99% .
Nano2iro n pr oduced by reductio n w ith g reen tea extr act ( GT2NIP) has g ood r emo val efficiency of hexav alent chromi2 um in w ater. It is ex pected that the remov al of hexav alent chr omium from gr oundw ater can be achieved in situ by injecting GT2 NIP into the aquifer; but this has not been verified yet. In this paper, we pr epar ed nano- ir on by reductio n w ith g reen tea ex2 tr act, measured its reductio n effect o n hex av alent chromium in w ater, and then used sand co lumn to study its remo val efficiency on hex avalent chromium in simulated g ro undw ater. The GT2NIP w e made w ere spherical and unifo rm in size, w ith a diameter of 10220 nm and g ood dispersion stability in w ater. They consisted o f 551 6% Fe2+ and 441 4% Fe3+ . When GT2NIP concent ratio n was 120 g/ L, after 1 h of r eact ion, the remo val rate of Cr( VI) w it h an initial concent ratio n o f 100 mg / L reached 9628% . In the co lumn test, GT2NIP could pass thro ug h the sand column, with an aver age outflow per centage o f 681 6% . When a Cr( ? ) so lu2 tion of 100 mg/ L was injected into t he sand co lumn, the concentrat ion of Cr 3+ w as abo ut 01 20 mg / L, and the concentr ation of Cr 6+ in the effluent was 01 10201 25 mg / L; that is, the to tal remo val r ate o f hex avalent chromium by GT2 NIP w as more than 99% .
2019, 17(1):138-143.
Abstract:
To fully understand the r eductio n effects of lar ch for est riparian buffer zones o n surface runoff po llutants, w e used am2 mo nium nitr og en and total pho sphor us so lutio ns o f three co ncentrations to irrig ate the larch fo rest riparian buffer zo ne in Weichang Count y of H ebei Pr ov ince at flow r ates o f 0. 67 L/s and 1. 82 L/s. The r esults show ed that the reduct ion effect of ri2 parian buffer zone on the ammonium nit rog en and total phospho rus in surface r unoff wo uld be enhanced w ith the increase of buffer leng th. At the same buffer distance in the riparian buffer zone, the reduction rates of ammonium nitrog en and to tal phos2 phor us in the smaller surface runo ff wer e bo th bet ter t han tho se in the larg er runo ff. With the increase of buffer dist ance, the differ ence of t he r eduction r ate o f ammonium nit rog en between smaller runoff and larg er runoff showed a trend of increasing first and then decr easing . When the polluted water flow ed throug h 20 m la rch for est riparian buffer zo ne, the influence of surface runo ff on the reductio n r ates of ammonium nitro gen and to tal pho sphor us became smaller in all t he po llution co ndit ions. At bo thruno ff vo lumes, the reductio n rat es of ammonium nitr og en and total phosphorus in the lar ch riparian buffer zo ne show ed the law s o f heav y pollutio n reductio n r ate > moderate pollutio n r eduction r ate > lig ht pollution r educt ion rat e.
To fully understand the r eductio n effects of lar ch for est riparian buffer zones o n surface runoff po llutants, w e used am2 mo nium nitr og en and total pho sphor us so lutio ns o f three co ncentrations to irrig ate the larch fo rest riparian buffer zo ne in Weichang Count y of H ebei Pr ov ince at flow r ates o f 0. 67 L/s and 1. 82 L/s. The r esults show ed that the reduct ion effect of ri2 parian buffer zone on the ammonium nit rog en and total phospho rus in surface r unoff wo uld be enhanced w ith the increase of buffer leng th. At the same buffer distance in the riparian buffer zone, the reduction rates of ammonium nitrog en and to tal phos2 phor us in the smaller surface runo ff wer e bo th bet ter t han tho se in the larg er runo ff. With the increase of buffer dist ance, the differ ence of t he r eduction r ate o f ammonium nit rog en between smaller runoff and larg er runoff showed a trend of increasing first and then decr easing . When the polluted water flow ed throug h 20 m la rch for est riparian buffer zo ne, the influence of surface runo ff on the reductio n r ates of ammonium nitro gen and to tal pho sphor us became smaller in all t he po llution co ndit ions. At bo thruno ff vo lumes, the reductio n rat es of ammonium nitr og en and total phosphorus in the lar ch riparian buffer zo ne show ed the law s o f heav y pollutio n reductio n r ate > moderate pollutio n r eduction r ate > lig ht pollution r educt ion rat e.
2019, 17(1):144-149.
Abstract:
This paper takes a long2distance w ater diversion project as the r esear ch object, and analyzes the ice develo pment law and ice hazar d o f the channel in w inter based on pro toty pe observat ion data. This paper intr oduces the lay out features of the channel and other co nstr uctions, the meteoro lo gical char acteristics in w inter, and the w ater convey ance mode in winter. It analy2 zes the ice phenomena in the ice drift period, fr eezing perio d, and thaw ing perio d, and t he ice distribution characteristics in differ2 ent years and areas. It summarizes the basic rules of ice formatio n and melt ing in the lo ng2distance w ater co nv eyance channel. Based on the special ice hazards in ty pical channels in winter, this paper lists such events as ice jam, w ater lev el decrease at fo re2 bay o f pumping station, flow rate decrease at div ersio ns, disto rtion o f instr ument readings, and canal lining fro st heaving . It ana2 lyzes the influence of meteor olog ical conditions, w ater conditio ns, and pr ojects lay out characteristics on the formation of ice haz2 ar ds. Fr om the perspectives of scheduling and engineering measures, this paper puts forwa rds a set of pr otectiv e measur es cover2 ing preventio n, blocking, interfer ence, fishing , and dra inag e acco rding to different channels and positio ns of the constructio ns in differ ent ice periods. It can pro vide t echnical support fo r t he safe and eff icient o perat ion o f long2distance w ater diversio n projects in winter.
This paper takes a long2distance w ater diversion project as the r esear ch object, and analyzes the ice develo pment law and ice hazar d o f the channel in w inter based on pro toty pe observat ion data. This paper intr oduces the lay out features of the channel and other co nstr uctions, the meteoro lo gical char acteristics in w inter, and the w ater convey ance mode in winter. It analy2 zes the ice phenomena in the ice drift period, fr eezing perio d, and thaw ing perio d, and t he ice distribution characteristics in differ2 ent years and areas. It summarizes the basic rules of ice formatio n and melt ing in the lo ng2distance w ater co nv eyance channel. Based on the special ice hazards in ty pical channels in winter, this paper lists such events as ice jam, w ater lev el decrease at fo re2 bay o f pumping station, flow rate decrease at div ersio ns, disto rtion o f instr ument readings, and canal lining fro st heaving . It ana2 lyzes the influence of meteor olog ical conditions, w ater conditio ns, and pr ojects lay out characteristics on the formation of ice haz2 ar ds. Fr om the perspectives of scheduling and engineering measures, this paper puts forwa rds a set of pr otectiv e measur es cover2 ing preventio n, blocking, interfer ence, fishing , and dra inag e acco rding to different channels and positio ns of the constructio ns in differ ent ice periods. It can pro vide t echnical support fo r t he safe and eff icient o perat ion o f long2distance w ater diversio n projects in winter.
2019, 17(1):150-156.
Abstract:
In o rder to study the applicat ion and effect o f sipho n2ty pe pipe sediment2discharg ing techno lo g y in dr edging of Xix i2 a yuan reser vo ir in the m iddle r eaches o f t he Yellow River, based o n the o n2site dredg ing test at the r eserv oir, w e utilized t he siphon effect o f the w ater level differ ence betw een the upper and low er reaches o f Xixiayuan Reserv o ir, alo ng w ith so il breaking jetting suctio n dr ag head fo r sediment reg ulat ion. T hr oug h tr acking and m onitoring the characteristic v alues such a s sediment concentra tion and flow r ate alo ng the sediment tr anspo rt pipeline, w e st udied t he sediment co ncentr atio n v ariatio n rang e, tr end, and particle size g r ada tio n at the measured po int under differ ent t est co nditio ns, and ca rried out qua nt itativ e a2 nalysis of the dr edg ing effect in the test . T he r esults show ed that w ith the incr ease o f the flow rate, the aver ag e sedim ent co ncentrat ion w o uld incr ease w hile the max im um sediment co ncent ration w o uld incr ease first and t hen decr ease. The m ax i2 m um sediment co ncent ration thr oug hout the test r eached 3 421 61 kg / m3 . T he pro duct ion co st fo r dr edg ing 2 0 00 m3 sedi2 m ent w as 105 600 yuan.
In o rder to study the applicat ion and effect o f sipho n2ty pe pipe sediment2discharg ing techno lo g y in dr edging of Xix i2 a yuan reser vo ir in the m iddle r eaches o f t he Yellow River, based o n the o n2site dredg ing test at the r eserv oir, w e utilized t he siphon effect o f the w ater level differ ence betw een the upper and low er reaches o f Xixiayuan Reserv o ir, alo ng w ith so il breaking jetting suctio n dr ag head fo r sediment reg ulat ion. T hr oug h tr acking and m onitoring the characteristic v alues such a s sediment concentra tion and flow r ate alo ng the sediment tr anspo rt pipeline, w e st udied t he sediment co ncentr atio n v ariatio n rang e, tr end, and particle size g r ada tio n at the measured po int under differ ent t est co nditio ns, and ca rried out qua nt itativ e a2 nalysis of the dr edg ing effect in the test . T he r esults show ed that w ith the incr ease o f the flow rate, the aver ag e sedim ent co ncentrat ion w o uld incr ease w hile the max im um sediment co ncent ration w o uld incr ease first and t hen decr ease. The m ax i2 m um sediment co ncent ration thr oug hout the test r eached 3 421 61 kg / m3 . T he pro duct ion co st fo r dr edg ing 2 0 00 m3 sedi2 m ent w as 105 600 yuan.
2019, 17(1):157-163.
Abstract:
The slo pe w ave pressur e calculation is hig hly empirical and has a w ide variety o f calculatio n fo rmulas. In order to ex2 plo re the applicability o f empirical fo rmulas in pr edicting t he pressur e o f landslide2g ener ated impulse w ave on the slo pe, we con2 str ucted a three2dimensio nal phy sical mo del of landslide2generated impulse w ave w ith a g eometric scale o f 1: 70. We studied the variatio n law o f slo pe wav e pressur e under the maximum and the effectiv e landslide2g ener ated impulse w aves under differ ent wo rking conditio ns. Three commo nly used empirical fo rmulas for slope w ave pressur e w ere used for comparison and analysis of the mag nitude, action po int positio n, and distributio n char acteristics of the pressur e of landslide2g ener ated impulse w ave o n the slope that was directly o pposit e the w ater entry point of the landslide. The r esults show ed that the results o f the three empirical formulas w ere quite different. Accor ding t o t he test r esults, the modified Subgr ade Fo rmula can be used to predict t he magnitude of the slo pe w ave pr essure under landslide2generated impulse w ave; the modified Fo rmula can be used to predict the br eaking point position of landslide2generated impulse w ave; the distribution t rend of the w ave pressur e o n the slo pe is consist2 ent w ith the So viet Standard Formula.
The slo pe w ave pressur e calculation is hig hly empirical and has a w ide variety o f calculatio n fo rmulas. In order to ex2 plo re the applicability o f empirical fo rmulas in pr edicting t he pressur e o f landslide2g ener ated impulse w ave on the slo pe, we con2 str ucted a three2dimensio nal phy sical mo del of landslide2generated impulse w ave w ith a g eometric scale o f 1: 70. We studied the variatio n law o f slo pe wav e pressur e under the maximum and the effectiv e landslide2g ener ated impulse w aves under differ ent wo rking conditio ns. Three commo nly used empirical fo rmulas for slope w ave pressur e w ere used for comparison and analysis of the mag nitude, action po int positio n, and distributio n char acteristics of the pressur e of landslide2g ener ated impulse w ave o n the slope that was directly o pposit e the w ater entry point of the landslide. The r esults show ed that the results o f the three empirical formulas w ere quite different. Accor ding t o t he test r esults, the modified Subgr ade Fo rmula can be used to predict t he magnitude of the slo pe w ave pr essure under landslide2generated impulse w ave; the modified Fo rmula can be used to predict the br eaking point position of landslide2generated impulse w ave; the distribution t rend of the w ave pressur e o n the slo pe is consist2 ent w ith the So viet Standard Formula.
2019, 17(1):164-177.
Abstract:
Concrete is a w idely2used building material, but it is pro ne to cracking during its serv ice life, especially in w ater conser2 v ancy pr ojects. The cracks not o nly affect the look of buildings, but also adv ersely affect the securit y of the str ucture. The tech2 nolog y of micro bial induced ca rbonate precipitation ( MICP) can be used to fabricate self2healing co ncr ete. This concrete can self2 heal when it has micro2cr acks, and thus has better durability and saves maintenance costs. T his paper summarizes and analyzes domestic and for eign literatur e o n the w or king mechanism of the self2healing concrete, the prepa ratio n methods, the characteris2 tics o f self2healing co ncr ete, and the affecting factors of self2healing effect. Reg arding the mechanism, it mainly int roduces the select ion of self2r epairing micro org anisms and the mineralization processes. Regar ding the pr epar at ion, it mainly summarizes the bacterial immobilizat ion methods used in self2healing concr ete. Reg arding the perfo rmance, it mainly analyzes the micro sco pic pr operties and macr oscopic propert ies o f self2healing co ncr ete. Reg arding the hea ling effect, it mainly summarizes three influen2 cing facto rs including r epairing agent compositio ns, curing conditio ns, and cracks char act eristics. Acco rding to the literature re2 v iew , the maximum w idt h of cracks that can be healed fo r self2healing concrete is 0. 97mm and the max imum depth is 271 2 mm.The self2healing co ncrete still has g reat dev elo pment po tential. Based on the curr ent research pr og ress, this paper points out the further research directions o f self2healing co ncr ete. It is aimed to push fo rw ard the dev elopment of this techno log y.
Concrete is a w idely2used building material, but it is pro ne to cracking during its serv ice life, especially in w ater conser2 v ancy pr ojects. The cracks not o nly affect the look of buildings, but also adv ersely affect the securit y of the str ucture. The tech2 nolog y of micro bial induced ca rbonate precipitation ( MICP) can be used to fabricate self2healing co ncr ete. This concrete can self2 heal when it has micro2cr acks, and thus has better durability and saves maintenance costs. T his paper summarizes and analyzes domestic and for eign literatur e o n the w or king mechanism of the self2healing concrete, the prepa ratio n methods, the characteris2 tics o f self2healing co ncr ete, and the affecting factors of self2healing effect. Reg arding the mechanism, it mainly int roduces the select ion of self2r epairing micro org anisms and the mineralization processes. Regar ding the pr epar at ion, it mainly summarizes the bacterial immobilizat ion methods used in self2healing concr ete. Reg arding the perfo rmance, it mainly analyzes the micro sco pic pr operties and macr oscopic propert ies o f self2healing co ncr ete. Reg arding the hea ling effect, it mainly summarizes three influen2 cing facto rs including r epairing agent compositio ns, curing conditio ns, and cracks char act eristics. Acco rding to the literature re2 v iew , the maximum w idt h of cracks that can be healed fo r self2healing concrete is 0. 97mm and the max imum depth is 271 2 mm.The self2healing co ncrete still has g reat dev elo pment po tential. Based on the curr ent research pr og ress, this paper points out the further research directions o f self2healing co ncr ete. It is aimed to push fo rw ard the dev elopment of this techno log y.
2019, 17(1):178-185.
Abstract:
Taking a pumping station of South2to2North Water Transfer Project as a model, we conducted full2channel numerical simula2 tion of the cav itation conditions of large2scale axial flow pumps in the pumping station during reverse power gener ation. We studied the steady and unsteady cavitation phenomena under the condition of reverse pow er generatio n, and compared the ex perimental results. We obtained the bubble vo lume distribution law under different cavitation co nditions, and predicted the development characteristics of blade cavitation. The pressure fluctuation of the three mo nitoring surfaces was studied under the condit ion o f r everse power g ener ation. The r esults showed that the pressur e fluctuatio n amplit ude w as the smallest at the g uide blade inlet and the lar gest at the runner outlet, which w as about 7 times of that at the runner inlet. The wat er flow was serio usly affected by the r unner ro tation and the main frequency was the frequency of t he runner. The amplit ude of pressur e fluctuatio n before and after the r unner wo uld in2 cr ease w ith t he decr ease of the cavitation co efficient under differ ent cavitat ion numbers, and the main frequency of pr essure fluc2 tuatio n w as not affected by the cavitation co efficient. T he sma ller t he cav itation number, the less the r adial fo rce o f the blade, the gr eat er the axial force, incr easing the instability o f the runner. To ensur e the stable and efficient operat ion of the axial flow pump in reverser power generation, the dev ice sho uld be running under a hig h cav itation co efficient.
Taking a pumping station of South2to2North Water Transfer Project as a model, we conducted full2channel numerical simula2 tion of the cav itation conditions of large2scale axial flow pumps in the pumping station during reverse power gener ation. We studied the steady and unsteady cavitation phenomena under the condition of reverse pow er generatio n, and compared the ex perimental results. We obtained the bubble vo lume distribution law under different cavitation co nditions, and predicted the development characteristics of blade cavitation. The pressure fluctuation of the three mo nitoring surfaces was studied under the condit ion o f r everse power g ener ation. The r esults showed that the pressur e fluctuatio n amplit ude w as the smallest at the g uide blade inlet and the lar gest at the runner outlet, which w as about 7 times of that at the runner inlet. The wat er flow was serio usly affected by the r unner ro tation and the main frequency was the frequency of t he runner. The amplit ude of pressur e fluctuatio n before and after the r unner wo uld in2 cr ease w ith t he decr ease of the cavitation co efficient under differ ent cavitat ion numbers, and the main frequency of pr essure fluc2 tuatio n w as not affected by the cavitation co efficient. T he sma ller t he cav itation number, the less the r adial fo rce o f the blade, the gr eat er the axial force, incr easing the instability o f the runner. To ensur e the stable and efficient operat ion of the axial flow pump in reverser power generation, the dev ice sho uld be running under a hig h cav itation co efficient.
25 Influence of height of throat section of elbow inlet channel on performance of vertical pump system
2019, 17(1):186-192.
Abstract:
In or der to ensure a goo d flow patter n when the w ater flows into the curv e, the end cr oss2 sectio n of the inlet of the el2 bow inlet flow channel usua lly has a small heig ht, and is called "t he thro at". Based on CFD numerica l simulatio n, we carried o ut scheme desig n and modeling calculatio n, co nduct ed quantitative analysis on the heig ht of the thr oat sect ion of the f low channel, and studied the inter nal flow stat e and pump system perfo rmance in each scheme. The r esults showed that t he scheme w ith a lar ge thro at height had a slow flow velocit y at the cur ve and small hydraulic lo ss, but the flow v elocity changed rapidly w ith un2 ev en distribution. The small height scheme had a fast flow velo city and larg e hydraulic loss, but t he flow v elocit y changed slow2 ly, with high uniform ity at t he o utlet. T he optima l solution fo r the throat heig ht in the study w as 01 8 times t he impeller diame2 ter. T he pum p system efficiency o f this scheme reached 791 08% at 340 L/s.
In or der to ensure a goo d flow patter n when the w ater flows into the curv e, the end cr oss2 sectio n of the inlet of the el2 bow inlet flow channel usua lly has a small heig ht, and is called "t he thro at". Based on CFD numerica l simulatio n, we carried o ut scheme desig n and modeling calculatio n, co nduct ed quantitative analysis on the heig ht of the thr oat sect ion of the f low channel, and studied the inter nal flow stat e and pump system perfo rmance in each scheme. The r esults showed that t he scheme w ith a lar ge thro at height had a slow flow velocit y at the cur ve and small hydraulic lo ss, but the flow v elocity changed rapidly w ith un2 ev en distribution. The small height scheme had a fast flow velo city and larg e hydraulic loss, but t he flow v elocit y changed slow2 ly, with high uniform ity at t he o utlet. T he optima l solution fo r the throat heig ht in the study w as 01 8 times t he impeller diame2 ter. T he pum p system efficiency o f this scheme reached 791 08% at 340 L/s.
2019, 17(1):193-201.
Abstract:
With the r apid urbanization of China, urban pluv ial floo ds and waterlo gg ing become incr easing ly frequent and serio us. Prev ious engineering measur es to alleviate urban w aterlog ging mainly focused o n impro ving the design standards of urban dr ain2 ag e system, lacking consider ation of o ther r elated pr oblems. Thus, we pr oposed a new multifunctional ur ban w aterlog ging con2 tr ol structur e2an under gr ound complex2to tackle the three urban pr oblems: waterlo gg ing, tr affic congestio n, and lay ing pipes & wires in the ut ility tunnel. The r eser ved ro om of the utility tunnel la yer in the under gr ound complex can effectively avo id repeat2 ed ex cavation o f r oads due to installatio n and repair of va rio us pipelines. The differ ent operat ion functions o f the traffic layer can effectively relieve the ur ban waterlo gg ing and t raffic pr essure. We put forw ar d an underg round complex str ucture scheme fo r the first time, established its 3D numerical mo del with ABAQUS, and conducted static analy sis. T he waterlo gg ing co nt rol effect of the underg r ound complex was analy zed based on the hy dr o2dynamic mo del and a case study. T he results show ed that the me2 chanical pro perties of the structure wer e reasonable; the v ertical displacement and stress w ere small in the two o per ating peri2 o ds. However, r einforcement sho uld be applied in t he tensile stress concent ratio n ar ea. The underg round complex can gr eatly al2 leviate the w aterlog ging situation of t he study area.
With the r apid urbanization of China, urban pluv ial floo ds and waterlo gg ing become incr easing ly frequent and serio us. Prev ious engineering measur es to alleviate urban w aterlog ging mainly focused o n impro ving the design standards of urban dr ain2 ag e system, lacking consider ation of o ther r elated pr oblems. Thus, we pr oposed a new multifunctional ur ban w aterlog ging con2 tr ol structur e2an under gr ound complex2to tackle the three urban pr oblems: waterlo gg ing, tr affic congestio n, and lay ing pipes & wires in the ut ility tunnel. The r eser ved ro om of the utility tunnel la yer in the under gr ound complex can effectively avo id repeat2 ed ex cavation o f r oads due to installatio n and repair of va rio us pipelines. The differ ent operat ion functions o f the traffic layer can effectively relieve the ur ban waterlo gg ing and t raffic pr essure. We put forw ar d an underg round complex str ucture scheme fo r the first time, established its 3D numerical mo del with ABAQUS, and conducted static analy sis. T he waterlo gg ing co nt rol effect of the underg r ound complex was analy zed based on the hy dr o2dynamic mo del and a case study. T he results show ed that the me2 chanical pro perties of the structure wer e reasonable; the v ertical displacement and stress w ere small in the two o per ating peri2 o ds. However, r einforcement sho uld be applied in t he tensile stress concent ratio n ar ea. The underg round complex can gr eatly al2 leviate the w aterlog ging situation of t he study area.
2019, 17(1):202-208.
Abstract:
In recent years, the continuous gr ow th moment um o f national wat er consum ption has been effectively cur bed by pro2 mo ting the construction o f water2sav ing societ y comprehensively . T he utilizatio n efficiency o f wat er r eso urces has been sig nifi2 cantly improv ed, and remarkable achievements have been made in w ater conservat ion in v arious industries. Acco rding to statist i2 cal analysis fr om 2010 to 2016, the to tal w ater co nsumpt ion and the proportio n o f each industr y chang ed little; w ater consump2 tion per 10, 000 yuan GDP fell by 36% ; the utilizatio n coefficient o f irrig at ion w ater increased from 01 51 to 01 54; w ater con2 sumpt ion per 10, 000 yuan of added industria l value fell by 42% ; the w ater2r eusing rate of the indust rial secto r increased to 881 3% ; the leakage r ate of ur ban public water supply pipe netw or k maintaied ar ound 15% . T her e is a lar ge gap betw een the current lev el of China and the internatio nal adv anced level in terms of water co nser vatio n in agriculture, industry and urban a re2 as. The co nstr uction of w ater2saving society has a long w ay to g o. As socialism w it h Chinese char act eristics enters the new era, ther e raises higher r equirements o n w ater security. At the same time, climate change has intensified the co nt radiction betw een e2 conom ic and social development and water resources security . T he water conservat ion cause faces a new situat ion and challen2 g es. This r esear ch discussed in2dept h the pro blems ex isting in the curr ent situation o f wat er conservat ion w or k in terms of the leg al standard, policy mechanism, scientific and techno lo gical innov ation, st at istical measur ement, manag ement system, and w ater co nser vatio n publicity . It puts forwar d the key points and sugg est ions for water co nser vatio n w or k in the new situat ion.
In recent years, the continuous gr ow th moment um o f national wat er consum ption has been effectively cur bed by pro2 mo ting the construction o f water2sav ing societ y comprehensively . T he utilizatio n efficiency o f wat er r eso urces has been sig nifi2 cantly improv ed, and remarkable achievements have been made in w ater conservat ion in v arious industries. Acco rding to statist i2 cal analysis fr om 2010 to 2016, the to tal w ater co nsumpt ion and the proportio n o f each industr y chang ed little; w ater consump2 tion per 10, 000 yuan GDP fell by 36% ; the utilizatio n coefficient o f irrig at ion w ater increased from 01 51 to 01 54; w ater con2 sumpt ion per 10, 000 yuan of added industria l value fell by 42% ; the w ater2r eusing rate of the indust rial secto r increased to 881 3% ; the leakage r ate of ur ban public water supply pipe netw or k maintaied ar ound 15% . T her e is a lar ge gap betw een the current lev el of China and the internatio nal adv anced level in terms of water co nser vatio n in agriculture, industry and urban a re2 as. The co nstr uction of w ater2saving society has a long w ay to g o. As socialism w it h Chinese char act eristics enters the new era, ther e raises higher r equirements o n w ater security. At the same time, climate change has intensified the co nt radiction betw een e2 conom ic and social development and water resources security . T he water conservat ion cause faces a new situat ion and challen2 g es. This r esear ch discussed in2dept h the pro blems ex isting in the curr ent situation o f wat er conservat ion w or k in terms of the leg al standard, policy mechanism, scientific and techno lo gical innov ation, st at istical measur ement, manag ement system, and w ater co nser vatio n publicity . It puts forwar d the key points and sugg est ions for water co nser vatio n w or k in the new situat ion.
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