| The study area located in the lower reaches of Yellow River in Henan province.Because the water table of Yellow River higher than the groundwater table of tworiversides in this section, the reaches section in study area is called over-ground river.To the whole Yellow River basin, the most cities located in the study area, and thepopulation centralized, industrial and agriculture economic developed, the amount ofwater consumption and water demand is large.Yellow River flow across the central section of study area, and the water tableof Yellow River is 3～10m higher than the ground of the river fluvial plainbetween Zhengzhou and Kaifeng section. The Yellow River water and the tworiversides groundwater has directly relation. To the whole Yellow River basin, thewater cycle among the atmospheric water, the surface water and the groundwatertakes on the most representativity.For near Yellow River, In longer time developing ,the region of two sides of theYellow River, the pattern of mainly using Yellow River water and groundwatersupplement is come into being. Yellow River is the most important water resourcesto the industry and agriculture production of two Riversides areas.For the reasons of high content of silt and sand of Yellow River water, runoffdecreasing, River water quality pollution, etc, the directly using Yellow River waterfaces more and more problems, and can't meet the growing water demand of theindustrial, agriculture and cities.To assure the study area economic continue development, on the basis of fullyusing the Yellow River water, groundwater must be scientifically developed andused. The precondition of scientific groundwater development is to have a clearlyunderstand for the groundwater circulation characters, including groundwater origin,formation, circulation velocity, renewable period, water connection andtransformation relations among different types of water bodies.The traditional methods to study the water circulation include hydrogeologicalstructure analysis , hydraulics analysis, hydrochemical analysis, and hydrochemicalkinetics analysis, etc. The isotopic techniques, as a effective method to studygroundwater ages, circulation velocity, renewable periods, recharge origin, rechargealtitude, water transformations between or among different water bodies, Sincebeing introduced into groundwater research in the fifty years last century, have beenplaying significant roles in water circulation qualitative or/and quantitative studies.That applying isotopic techniques to investigate and ascertain the hydrologicalcycle characters of study area takes on very important practical meaning andacademic significance.For the close transformation relations among atmospheric water, the surfacewater and the groundwater , the groundwater cycle research must be combined thecharacters of atmospheric water and Yellow River water.In the study, based on the precipitation isotopes data of and around study area,collected from IAEA, the characters of deuterium (D), oxygen(18O) and tritium(3H)in the precipitation of study area are comprehensive analyzed. The followingvariations of isotopic characters in precipitation are discovered:The correlations between D and 18O in precipitation is very well, and therelationships of D, 18O with the precipitation and air temperature are negativecorrelation, and the highest D and 18O occurs respectively around March and July.The whole variation tendency of D and 18O in precipitation is that, in the time fromMarch to May, the first wave peak occurs, and then the value slowly decreases, inthe time of June to September, a wave trough occurs, and in the time of Septemberto November the second wave peak presents, and then December to February nextyear, the second wave trough occurs.The tritium peak presents in warmer half-year, and according to the hightemperature period. No well correlation between Monthly precipitation and thetritium of it. The yearly variation of tritium in precipitation is large. And thevariation of tritium value of monthly precipitation in a year take on gradually changein warm half-year (April to September) , and take on oscillate variation in cool half-year (October to March) when the tritium value of July being get rid of.The affect factors are analyzed to the variation characters of D,18O and 3H inprecipitation of study area. Through research, the representative monsoon climateand the oneness topography and geography of the study area are the essential factorsto control the isotopes in precipitation taking on upper variation rules to study area.Additionally, the unique source or multi-sources of isotopes in precipitation is one ofimportant factors too. In the study, the deuterium excess is discovered being a goodparameter to reflect the different water origin of precipitation to different seasons instudy area.Including Hélène method recommended by IAEA, etc ,four methods have beenused to recovery the historical tritium concentration series in precipitation of studyarea. By comparing the results obtained via different methods, the final result of thetritium concentration series in precipitation of study area is determined, and soproviding the base data for the groundwater age determination via tritium method.The study about isotopes to Yellow River in study area is precondition toascertain the influence range of Yellow River .For being over-ground River, theisotopes characters of Yellow River in study area is determined by the isotopes of theupstream water. In this research, from the relations of up reaches and lower reaches,the Yellow River isotopes are analyzed, and the variation rules of isotopes in timeand space are discovered. The isotopes variety characters of Yellow River aredifferent in different seasons and different sections. To analyze the variety charactersand the affect factors to isotopes of Yellow River, the following aspects are analyzed,including the altitude effect, the continental effect, seasonal positive or negativeeffect, the variable contribution of the recharge sources in different season, theevaporation effect, the sole source or multi-sources of isotopes in precipitation , andthe deuterium excess characters, the hydraulic engineering , and the correspondingrelations between the isotopes of Yellow River and the "three large terrace ofChina",the climate zone, the temperature zone of china continent. And so supplyingthe necessary conditions to ascertain the influence range of Yellow River.The groundwater cycle study is the main content in this dissertation. Becausethe close relationships of "three water" cycle in study area, the groundwatercirculation research must be combined the study results of precipitation and YellowRiver water.Based on more than 100 groundwater isotopes data collected in three periodsfrom 2000 to 2001, combining the hydrogeologic conditions and the meteorologicconditions and the hydrologic conditions, the characters of D, 18O,3H,d,13C(2000.8),and the hydrochemical data(2000.8,2001.4), are comprehensive analyzed inplane, section lines and different depth in vertical sections in specific zones. On thebasis of isotopes and the chemical data study, the following news about the watercycle in the study area are obtained.The origins of the phreatic water and the confined water are precipitation, andin the formation process, both are affected by evaporation. The formationenvironment of the phreatic water and confined water are a little difference.According to the 18O temperature indication relation, the confined water formationenvironment is 2.2℃ lower than that of phreatic water. The recharge source of theunconfined water of study area mainly from the local precipitation water. And thewater cycle mainly takes place on vertical direction, including infiltration fromprecipitation and irrigation, the evaporation and exploitation. And the lateral watercycle velocity is slow.The isotopic values of Yellow River are close to the riversides phreatic waterand large different relatively to confined water. The peculiarity indicate the closerelations between the Yellow River water and the unconfined water near riversides,and this is according to the practical hydrogeological conditions of the study area.From the tritium characters of the Yugong spring water (the Ordovician karstwater), the spring received precipitation water recharge after nuclear test. And thewater cycle velocity is fast and the cycle period is shorter than the quarternaryconfined water. And the recharge area is located in northern Taihang Mountains.The deuterium excess character indicates the exchange effect between water androcks is little. And further indicating the good runoff conditions and the short cycleperiod of the Yugong spring water. That the chemical water type becomes complexin dry season (Ca-Mg-HCO3-SO4 in April) compare to rainy season (Ca-Mg-HCO3in August) indicate the water cycle velocity is obviously affected by the variationhydraulics kinetic conditions, and at the same time, indicating the fast response ofthe Yugong spring water system to environment.Compare to the ordovician karst water(40,44), the chalky clay water(41,42)northern of Xixiang have the higher oxygen-18 and lower deuterium excess in2001, indicating the slower water cycle velocity ,the longer water cycle period, thelonger residence time, and the obviously oxygen-18 exchanging between karst waterand rock.There are some abnormal isotope value samples in the collected samples. Thesample of number 92 in Liuji village of Zhongmou county has been affected bymixing role of evaporation water. And the number 82 in Xinxiang showingobviously mixing role. Most of samples of the phreatic water and part samples ofconfined water(for instance, near Yellow River ,among the confined watersamples ,the number 12 , 76(north in Zhengzhou city) and 49(Yuanyangcounty))collected in April 2001 have been recharged by the precipitation afteratomic test. Some samples among the unconfined water are recharged before 1953,for instance the number 32(Puyang), 45(Funingji village of Xinxiang county),91(Liangjia village of Zhongmou county), reflecting the water cycle velocity is slowin these locations. The reason for the low tritium phenomena to the unconfinedwater is correlated to the heterogeneous of aquifer in the location, and besides, thatthe depth of the water samples collected may be a affected factor too.The width of Yellow River is ascertained by the isotopes D,18O,3H ,andconfirmed by deuterium excess.Comparing to the isotopes of the phreatic water in study area, Yellow River hasthe characters of lower deuterium and oxygen and higher tritium. This characterprovides favorable conditions to ascertain the affection width and depth of theYellow River water.Via the "∧"shape of deuterium excess along the section lines, the affect widthof Yellow River determined by the isotopes of deuterium ,oxygen-18 and the tritiumis verified and confirmed . Through comprehensive analyses, the affect width ofYellow River water to the groundwater in four section lines are ascertained asfollowing:Zhengzhou section line: northern bank of Yellow River is 8km, southern bankof Yellow River is 4.9km;Xinxiang to Zhongmou section line: northern bank of Yellow River is 24km,southern bank of Yellow River is 14.7km;Fengqiu to Kaifeng section line: northern bank of Yellow River is 23km,southern bank of Yellow River is 17.8km;Puyang section line: northern bank of Yellow River is 4.9km.The affect depth of Yellow River is determined via isotopes as following:Zhengzhou section: the affect depth is small than 300m , corresponding to thenumber 76.Xinxiang-Zhongmou section: the affect depth is 160m, corresponding to thenumber 49.Fengqiu-Kaifeng section: the affect depth arrive to 175m, corresponding to thenumber 17.Considering two instances in the shallow water age determination, one ignoresthe infusion and mixing of tritium in aquifer media by using the TRACER model,and another considering the infusion and mixing of tritium in aquifer media byPCFLOW model. The results indicate that considering the infusion and mixing oftritium in aquifer media is better quality and according to practical conditions.Considering the residence time of tritium in vadose zone, the shallowgroundwater transit time (including the infiltration time in vadose zone and theresidence time in saturated zone) is 27.7a, and the phreatic water age is 20.85a .According to the characters of deuterium and oxygen in vertical profile, therecharge velocity and recharge amounts of precipitation to groundwater in study sitais calculated by using the method of isotopes peak displacement. By comparing tothe result of the field infiltrometer method and precipitation coefficient method, theisotopes method result is ascertained and the results is reliable and accurate.The isotope method is proved a convenient, efficient, and economic method tostudy the recharge of precipitation to groundwater. And the method has considerablyapplying potentiality and utilizing value.The carbon-14 age of deep groundwater is Corrected ,and then the hydraulickinetic characters of the deep confined water is researched. The following watercycle news are obtained:Southern of Yellow River ,with the distance far away from Yellow River, theconfined water age is gradually old ,and the representative samples are number12 →76, and number 17→ 27.From the top to the edge of the alluvial fan of Yellow River, along the flowingpath, the age of groundwater gradually increasing.From Huayuankou (number 73 , 75), the upper reaches →Yuanyang(number49,56) →Yanjin→Puyang(number34,35),the lower reaches,the groundwater age gradually increasing. That the water age in ZhengzhouHuayuankou(upper reaches) is minimum (bound in 430-1985a),and the water age inPuyang(lower reaches)is maximum(bound in 24000～27400a).The velocity range of deep confined water is 0.19～6.5m/a .According to the distance and the difference of water age of two adjacentsamples, the velocity in different routes is determined as follow:Number 12→76: the velocity of confined groundwater is 0.19m/a.Number 17→27: the velocity of confined groundwater is 1.76m/a.Number 75→49: the velocity of confined groundwater is3.45m/a.Number 75→56: the velocity of confined groundwater is 6.5m/a.Number 49→34: the velocity of confined groundwater is 5.76m/a.Number 49→35: the velocity of confined groundwater is 5.83m/a.Number 56→34: the velocity of confined groundwater is 4.75m/a.Number 56→35: the velocity of confined groundwater is 4.8m/a.Number 80→90: the velocity of confined groundwater is 2.15m/a.The groundwater age obviously increase with the depth increasing.Therepresentative sample is that the number 73 in Zhengzhou(150m)with the age lessthan 430a → number 76 in Zhengzhou(300m)with the age more than 16000a.Reflecing the water cycle velocity slowering with the depth increasing, and therenewable period enlargement.The sample well of number 73 with the depth of 150m, in Zhengzhou, has theminimum water age(little than 430a), considering the sample location , we cananalyze that large amounts of shallow water mixing into the deep water with theexploitation of deep groundwater.The water age of number 82(confined water) in Xinxiang varied obviously inrainy season and in dry season, and the water age in rainy season less than the age indry season. This reflects the deep water in this location is obviously affected by thehydraulic kinetic conditions variation. And at the same time, reflecting the leakingrecharge of upper shallow water to lower deep water, ascertaining the watercorrelation between shallow water and the deep water in the location. In contrast, thewater age of 49(Yuanyang paper manufactory) and the 90 (Zhongmou fertilizermanufactory) are no change in rainy season and in dry season, considering thedegree of accuracy of carbon-14 in aging the groundwater. The phenomena reflectsthe hydraulic kinetic information of the slow groundwater velocity, and the watercycle information of no mixing happens between shallow water and deep water inthese locations.In research, the water cycle characters of study area are systematicly studied byusing isotopes techniques. By using the isotopes method, the influence width and thedepth of Yellow River, the recharge velocity and the amount of precipitation togroundwater, the age and transit time of shallow water, and the hydraulic charactersof deep water, and the transformation between the shallow water and the deep water,etc. are determined. The results obtained by isotopes according to thehydrogeological conditions of the study area. This ascertains the isotopes techniquebeing a good method in water cycle characters study.
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