PINSTECH/RIAD-132
ISOTOPIC STUDY OF WATERLOGGING AND SALINIZATION IN PESHWAR VALLEY
R. M. QURESHI M. I. SAJJAD M. AHMED S. D. HUSSAIN M. A. TASNEEM P. FRITZ
RADIATION AND ISOTOPE APPLICATIONS DIVISION Pakistan Institute of Nuclear Science & Technology P. O. Nilore, Islamabad April, 1992 PINSTBCH/RIAD-132
ISOTOPIC STUDY OF WATERLOGGING AND SALINIZATION IN PESHAWAR VALLEY
R. M. QURE8HI M. I. 8AJJAD M. AHMED S. D. HUSSAIN M. A. TA8NEEM P. FRITZ *
RADIATION AND ISOTOPE APPLICATION DIVISION PAKISTAN INSTITUTE OF NUCLEAR SCIENCE AND TECHNOLOGY P. O. NILORE, ISLAMABAD
April, 1992
* Scientific Director General, Umwelt Forschungzentrum, Liepzig, F. R. Germany inil*n**
.* f \
ABSTRACT
A detailed account of the application of isotope and geochemical techniques in the study of waterlogging and salinization of agricultural lands in the Peshawar valley area is presented. Precipitation samples, surface/groundwater samples and aqueous sulphate were analysed for tritium and stable isotope ratios of hydrogen, oxygen and sulphur. The data show that the artesian aquifer is recharged by the precipitation at high mountains whereas local precipitation and irrigation canal waters are mainly responsible for the recharge and waterlogging in the unconfined aquifer. In some parts of the valley, upward leakage from artesian water is found to cause waterlogging. The valley area contains water recharged after 1953. The chemical quality of the shallow groundwater is quite poor as compared to that of deep groundwater.
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"™^»! CONTENTS 1. INTRODUCTION 1 2. PROJECT AREA 1 3. ISOTOPIC AND HYDROCHEMICAL INVESTIGATIONS 3 3.1 FIELD AND LABORATORY METHODS 3 4. RESULTS AND DISCUSSION 4 4.1 ISOTOPE INPUT FUNCTIONS 4 4.2 ISOTOPIC COMPOSITION OF GROUNDWATER 5 4.2.1 SPATIAL DISTRIBUTION OF ISOTOPIC DATA 5 4.2.2 VERTICAL DISTRIBUTION OF ISOTOPIC DATA 6 4.2.3 RELATIVE CONTRIBUTIONS FROM DIFFERENT INPUT SOURCES 6 4.2.4 SULPHUR ISOTOPE COMPOSITION OF SULPHATE 7
4.2.4.1 34S INSULPHATES OF SOIL CORES 8 4.3 CHEMICAL QUALITY OF SURFACE AND SUB-SURFACE WATERS 8 5. CONCLUSIONS 9 6. REFERENCES 10 ISOTOPIC STODY OF WATERLOGGING AND 8ALINIZATION IN THE PESHAWAR VALLEY
1. Introduction A detailed account of the application of isotope and geochemical techniques in the study of waterlogging and salinization in the Peshawar valley is presented. Water samples from the irrigation canals, open wells and pumping wells were analyzed for tritium and stable isotope ratios of hydrogen and oxygen. Aqueous sulfate from water samples and sulfate (soluble as well as adsorbed)extracted from the soil cores were also analyzed for £3AS. In addition, precipitation samples have been collected to determine the isotopic index of rain water. These analyses were used to determine : a) the potential sources of recharge in the shallow unconfined aquifer and the artesian aquifer, and b) the extent of mixed waters in the Peshawar valley in terms of effects on the chemical quality of shallow groundwaters.
2. Project Area The Peshawar Valley with a gross area of 911 square kilometer (of which 773 square kilometer are culturable) is situated between longitutdes 7l°-23' to 71°-55'E and latitudes 33°-50 to 34°-10'N (figure 1). The area has a subtropical and semi-arid climate. Summers are hot and dry in June and and very humid in July and August. Winters are relatively cold with light frost in December and January. The mean monthly maximum and minimum temperatures range from 17-40 °C and 4-26 °C respectively. The average annual precipitation amounts to about 380 mm. The Peshawar valley is tectonically unstable and has many faults and folds. The mountain ranges bordering the valley area on the west, southwest and southeast consist of a complex and highly indurated and structurally deformed sedimentary and metamorphic rocks ranging in age from Precambrian to Tertiary. The extension of these mountains form the bed rock under the alluvium of the valley area. Simultaneous deposition of the alluvium and erosion gradually changed the land surface. The land altitude varies from 290 m to 442 m above the mean sea level with a general slope of 3 m per kilometer towards north-east.
Hydrologic characteristics of the sediments in the valley were obtained by the Water and Soil Investigations Division (WASID) of the Water & Power Development Authority (WAPDA). The average porosity determined from the repacked drill cuttings is about 42.4 percent. Groundwater in the valley mainly occurs in the alluvial deposits of quarternary age. The rocks on
1 the west, southwest and south form the impermeable boundary of the groundwater reservoir. The groundwater occurs under water table conditions and also under artesian conditions. The general movement of the groundwater is from the southwest towards the river Kabul. The exact extent of the artesian zones is not yet defined and it appears to extend from the Khyber hills towards the city of Peshawar where it has been observed at shallow depths of 15 m [WAPDA, 1973]. History of canal irrigation in the valley dates back to some 300 years - the time of Moghul Emperor Aurangzeb. Regulated canal system came into being with the construction of the Kabul river canal in 1893 and with the development of Warsak Dam high level canal system (Gravity flow canal and the Lift canal). Several small inundation channels known as Kaphas offtake from the Kabul and the Bara rivers. Also, the valley is traversed by numerous torrents locally known as Khawars coming down from the hill ranges in the south and southwest. In the Peshawar valley, the geological formations contain extensive clayey deposits with shingle beds, silt and clayey stratifications. The sandy beds in the area are also not as much water yielding as under the Indus plains. The water table and soil salinity levels of the valley have been continuously increasing since the development of canal irrigation system. This irrigation scheme has resulted in the rise of water table within a meter or so of the general land surface in some parts of the irrigated areas of the valley alongwith the development of soil salinity which retards the crop growth considerably. According to a study by WASID the water table was rising by 1.5-2.5 m per year adjacent to the Warsak canal system. Nearly 10 percent (91 square km ) of the area was affected by salinity of which 4.1 percent was severely saline. Since 1979-80, WAPDA installed more than 200 pumping wells (tube wells) and a number of dug wells in the area, under the SCARP program to pump groundwater continuously from depths of 15-60 meter in order to decrease the water table [WAPDA,1973]. However, the water table has not significantly dropped and a considerable portion of the valley still shows patches of surface water. A number of open wells in the area show water table 1 meter below general land surface. A number of tube wells are flowing under artesian conditions. Although the surface salts have been washed down at many places due to the recycling of canal-fed irrigation waters, the SCARP programme, in general, has not yet resulted in a perma nent solution to the problem [Mushtaq, 1985]. In many areas, the continuous pumping by the tube wells has not proved efficient in lowering the water table and the salts reappear on surface in the early winter season. Previous studies by the WAPDA indicated that a major emphasis was given to the physical hydrology of the Kabul river basin for water resources development for agricultural purposes and no particular attempt was made to look at the origin of salinity and the long term consequences of the
2 extensive unlined canal irrigation practices towards waterlogging. In this report an attempt is made to utilize i sot ope- geochemical techniques in order to identify various hydrological and hydrogeochemical features developed after the completion of SCARP programme in the Peshawar valley. 3. Isotopic and Hydrochemical Investigations 3.1 Field and Laboratory Methods a) Water Samples: Figure 2 shows the location of sampling points in. the Peshawar valley. Water samples from open wells, pumping wells (tube wells) and irrigation canals were collected on quarterly basis. Only those open wells were sampled which are frequently used by the local population for drinking/irrigation purposes. Canal samples were taken at specific locations during each sampling trip. All water samples were collected in doubly stoppered bottles to avoid evaporation losses. These samples were used for isotopic and chemical analyses. pH, EC and temperature of all samples were measured in the field. Aqueous sulphate was precipitated in the field as barium sulphate by the addition of barium chloride in mildly alkaline water samples. Precipitation samples after each rain event were collected at a permanent station located in the Peshawar city. Due to the sensitive nature of the area it was not possible to install a proper meteorological station in the mountainous areas. Therefore, all the isotopic data for precipitation correspond to the single sampling station. Precipitation samples were collected with a simple funnel-and-bottle arrangement.
180,2H,3H in water molecules and all hydrochemical analyses were performed in the Isotope Hydrology Laboratories at PINSTECH. All stable isotope analyses are expressed in the conventional s%o(delta per mil) notation and referred to the standard SMOW (Standard Mean Ocean Water) for all 180, 2H analyses and to CDT (Canon Diablo Troilite) for all 3t,S analyses of sulphate. Measurements of standards and samples indicate the overall analytical error below + 0.1 %o for 180 and ± 1 %o for ZH in case of water samples. 34S composition of the aqueous sulphate was performed at the Isotope Geochemistry Laboratory, Department of Earth Sciences, University of Waterloo, Canada. Measurements of sulfate standards and samples indicate the overall analytical error below ± 0.3 %o for3 *S.
Tritium analysis was mostly performed using direct counting method (precision ± 10 TU).
b) Soil Core Samples: Soil cores from 1-1.5 meters depth were collected from various representative soils in the Peshawar valley as described by WASip. Each core was divided into 10 cm samples and packed in polyethylene bags. Each soil sample was
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manually mixed and the soil soluble as well as soil adsorbed sulphate was extracted in the laboratory by shaking a portion of the soil sample in 0.1M NaCl water (water to soil ratio = 1:1 by weight). These solutions were first coarse filtered through Watman #40 filters and then through 0.45 micron nitrocellulose filters. A portion of the filtered solution was analysed for sulphate ion concentrations, The remaining portion was treated with BaCl,.2H 0 to precipitate barium sulphate for sulphur isotope analysi2s of aqueous sulphate. 4. Results and Discussion 4.1. Isotope Input Functions a) Precipitation: Figure 3 shows the 180 and 2H data obtained from precipitation in the Peshawar valley for the period 1982-1985. The regression line is obtained by considering all the monthly weighted isotopic data. It thus represents the local meteoric water line (LHWL) which is as:
SD = (7.1 ± 0.43) 5180 + (9.6 ± 2.54), Coff.corr= 0.97 Leaving the isotopic values greater than 0 %o, the regression line for local meteoric water(LHWL) becomes:
SD = 7.47 6180 + 10.41
Averaging all monthly weighted isotopic data for 618o and SD, and assuming the slope of '8' , the LMWL becomes:
SD = 8 £180 + 13.37 This line as shown in figure 4 is identical to the regression line of precipitation data at Sargodha [ Hussain,et. al., 1990] which is as:
SD = 8 «180 + 14 The isotopic data of two artesian wells(45,ill) fits exactly in the above equation. This data is a true representation of rainfall at the mountains as it is least affected by any other source because of the nature of the aquifer and recharging zone. This further supports the above findings. The weighted annual averages for precipitation for the years 1983-85 are:
*1sO =-5.7 %o SD = -30.8 %o
3H - 36 TU d = 14.8 %o
4 b) Surface waters: Figure 5 shows the seasonal variations in the irrigation canal waters derived from the Warsak dam/Kabul river. The stable isotope contents of these waters are significantly depleted as compared to the local precipitation because these waters originate from the snow-melt areas in Afghanistan. Notable are the depletions during summer (July -Sep.) which is the period of significant snow-melt. The range of isotopic variations of the irrigation canal waters is:
5180 = -13 to -11 %o, 5D = -82 to -72 %o and 3H = 54 to 64 TU In the absence of enough available isotopic data of canal samples, the average isotopic value of the canal waters was evaluated by taking into account the average isotopic composition (1982-85) of the pumping wells #18, 19, 21 and 22. These wells are grouped together and are enclosed by the canals namely: Kabul river canal and Bundni canal, very near to Warsak H/works. Moreover, the location of these wells is such that any influence of irrigation water and local rains is not possible. The computed isotopic values of the irrigation canals are:
5180 = -11.4 %o, SD = -71 %o and
3H =58 TU
The average isotope composition of 634S in the aqueous sulphate of irrigation canal waters is +3.2 %o. 4.2 Isotopic Composition of Groundwater
Figures 6-15 show the spatial variations of £180, SD, tritium contents; SD-S^O diagrams of the isotopic data for the months of July 1982, November 1982, June 1984 and mean values of all isotopic data of groundwater over the period of study; normal cumulative probability plot; frequency histograms of 5180 and tritium data. 4.2.1 Spatial distribution of isotopic data Figures 6 & 7 show spatial distribution of 6180 and 5 \ -12 and -6.5 %o are common. Tritium data of groundwater do not show any specific spatial trend (figure 14), however, its frequency histogram (figure 15) shows three major peaks at 30, 55 and 70 TU. 4.2.2 Vertical Distribution of Isotopic Data Figure 13 depicts 5180 frequency histogram of deep and shallow waters. The deep waters have a major peak around *180 = -6.5%o while the shallow waters around -10.5 %o. There is no specific trend in the tritium data. 4.2.3 Relative contributions from Different Input Sources Figure 12 shows a normal cumulative probability plot of £180 of groundwater. The plot has four straight lines 1-4 indicating different types of waters recharging the aquifer. Line no.l has middle point at £180 = -5.3 %o close to the isotopic index of local rains (5180 = -5.7 %o). Sampling points lying on this line are recharged by local rains. Line no.2 has mean 5180 value equal to -6.3 %o. Sampling stations of this line belong to the Peshawar city and its nearby area. Two flowing artesian wells (sampling well nos. 45 & 111) have mean 5180 = -6.2%o. As these wells are flowing under pressure, any contribution from other sources would be the least. The source of recharge to this artesian aquifer seems to be the rainfall on the outcrop hills surrounding the Peshawar valley. The difference in £180 of this source from the local rainfall is [-6.3-(-5.7)] -0.6 %o. Assuming the altitude effect in £180 equal to -0.3 %o per 100 m, the mean altitude of mountains recharging the confined aquifer is about 200 m. Line no.3 represents mixing from canal system, and the artesian aquifer(which is recharged by the rains). Mixing of the two systems is through leakage from the artesian aquifer to the unconfined shallow aquifer through the screen of the tubewells penetrating the artesian aquifer. Because the tubewells are not uniformly screened and are installed at different depths, they tap variable proportions of the shallow unconfined aquifer and in certain cases also tap the artesian aquifer. Therefore, waters discharging from such wells have isotopic compositions which depend upon the degree of mixing between waters from the pre- irrigation watertable in the unconfined aquifer, artesian waters with shallow subsurface waters and/or the induced infilteration from canals. This, however, does not hold true for the Peshawar city where the stable isotopic composition of the cased wells is similar to the stable isotope composition of precipitation at mountains. The irrigation canals are not properly lined in the city area and the leakage from canals has contributed to the shallow groundwaters in the city area as well. The extent of mixing of canal waters with the precipitation waters can also be seen from figure 12. 6 \ Line no.4 has central value at $inO = -11.6 %o identical to the isotopic index of canals (-11.4 %o). Sampling points on this line represent areas which are recharged exclusively by the canal system. 4.2.4. sulphur Isotope Composition of sulphate Figures 16 and 17 show the sulphur isotopic composition and the concentration of the aqueous sulphate in surface and subsurface waters of the Peshawar valley. Sulphur compounds in groundwaters have the similar sources as those in surface waters. However, the isotopic composition of groundwater sulphur compounds may be affected more by geochemical processes than surface water sulphate. Sulphate in surface waters may come from and have 5WS values characteristics of sulphate in atmospheric dust dissolved in precipitation, solution of soil sulphate, evaporite minerals, from oxidation of sulphide minerals and soil organic sulphur. Early isotopic studies of sulphates in atmospheric precipitation found £34S values in the limited range of + 3.2 to +8.2 %o in the non- industrial regions, but high values as +15.6 %o in industrial areas, correspond to the 3*S contents of coal burned locally [Fritz & Fontes, 1985]. In the New Zealand study, Mizutani and Rafter [1969c] found that the isotopic composition of excess sulphate {that sulphate present above sulphate which would be present from sea spray alone} itself was in the range of -2 to -4 %o. Other sources of excess sulphate in rainfall, particularly in arid zones, may be the dispersion of mineral sulphates by wind from evaporite deposit at the surface or from sulphate minerals which have precipitated from terrestrial surface water in playa or saline environments or in oil. In case of Peshawar valley, the sulphur isotopic data clearly indicate two distinct areas as mentioned below: a) Positive £3*S values dominate in the sulphates of canal/local rain recharged areas or in the areas having greater proportion of canal/local rain water. b) Negative S34S values dominate in the sulphates of artesian aquifer recharged areas or in the areas having more proportion of rains at mountains. Canal R«charg«d Areas: The areas in which the de values of groundwater are between -11.4 to -7.0 %o are believed to be recharged by canal system. We see that the river/canal system have «S"S in dissolved sulphate equal to +3.2 %o and the river is fed by snowmelt and rainfall at high mountains where industrial influence would be minimum. Therefore, we believe that the local rainfall have 534S more than +3.2 %o. Consequently, all the wells solely taping the unconfined aquifer have positive cS3*S values in the range 2-7 %o. So the source of sulphate here is 7 river and local rainfall. Another process which would have slightly enhanced the sulphur isotopic composition of aqueous sulphate, is the bacterial sulphate reduction which is common to water-logged areas. Confined Artesian Aquifer: Wells taping confined artesian aquifer (with £180 around -6.5 %o) have very depleted «34S values in the range of -7.0 to -0.1 \o, with quite different source of sulphates compared to unconfined aquifer. These depleted values could be due to excess sulphate in rainfall at mountains recharging the confined aquifer (as discussed above) or these waters might have received sulphate presumably derived from sulphide at the source of recharge or along their flow path. This is due the fact that sulphide minerals which tend to be isotopically lighter than sulphate minerals, the sulphate produced by oxidation of sulphide minerals may be more depleted in34 S. 4.2.4.1 «34S in sulphates of Soil Cores Figure 18 shows the concentration of soil-extracted sulphate and the respective £3*S values with depth for three cores taken from active saline and water-logged zones in the Peshawar valley. Soil core no. 5 is taken from the water-logged zone near sampling location no. 45, soil core no. 10 near location no. 55 and soil core no. 20 in the Kafur Dheri Banda area close to Warsak dam. Soil cores 5 and 20 indicate an enrichment in the 53*S with depth. The enrichment in 53*S associated with loss of sulphate concentration as in this case, is due to bacterial sulphate-reduction in the upper soil layers. In the deeper soil layers both sulphate concentration and 534S become more or less constant. Soil core no. 5 being located close to flowing artesian well no. 45, has depleted £34S values (-4 %o) compared to soil core no. 20 which has mean £34S equal to +8 %o. Soil core no. 20 is recharged only by rains and as a consequence its sulphate isotope composition is reflected in the soil core. Soil core 10 has large fluctuations in 534S with depth while its sulphate concentration is rather low and constant. Its 53*S has rang.3 of +14 to +30 %o. Its sulphate cannot be derived from oceanic evaporite( 534S = +20 ± 10 %o) as the sulphate concentrations are very low compared to other two soil cores. The high enrichment in 5"S can perhaps only be due to bacterial reduction process of sulphate in which the remaining sulphate becomes enriched and such a process is always associated with the loss of sulphate concentration. 4.3. Chemical Quality of Surface and Subsurface Waters Groundwater quality studies carried out by WASID in the valley prior to the development of the SCARP indicate that the salt concentrations in the shallow groundwaters (from 1-25 m) were between 185-3200 ppm and that in the deep groundwaters (from 8 25-140 m) were between 196-2000 ppm. Analyses of soil series in the valley area gave soil pH values between 7.6 to 9.2 [WAPDA, 1973]. The chemical quality of surface and subsurface waters in the Peshawar valley several years after the establishment of the Peshawar SCARP programmes by WAPDA and during the period 1982-83 have been investigated. The analyses show that the pH values of surface waters (irrigation canals) is higher than the subsurface waters by about 0.4 to 1.4 pH units. The pH of most subsurface waters is around 7.5. The electrical conductivity of surface waters is very low (155-171 umhos/cm.) upstream and increases downstream by a factor of two for the Kabul River Canal near the Peshawar city area and by a factor of about four at the end of Jue-Zardad (a branch of the Budni Canal). This increase in the electrical conductivity is due to the input of domestic waste water into the canals. Significantly high electrical conductivity (upto 2070 umhos/cm.) is seen in shallow groundwaters (open wells) as compared to the deep groundwater of the unconfined aquifer and the artesian waters. The present water quality survey indicates that the SCARP program has overcome the problem of salinization of the groundwater and that the electrical conductivity values for the shallow groundwater are within the marginal limits (1500- 3000 umhos/cm.) for agricultural purposes and those for the pumping wells are within the usable limits (0-1500 umhos/cm.) for agricultural purposes. The chemical analyses of surface and subsurface waters show that sulfate and bicarbonate are the major anions in the water of the Peshawar valley area. There again, the irrigation canal waters have very low concentrations of these anions. These analyses are in agreement with the previous analyses carried out by WASID [WAPDA, 1973). 5. Conclusions The available isotopic data of the water molecules clearly shows that precipitation at mountains is the single major source of recharge to the artesian aquifer whereas local precipitation as well as significant amounts of irrigation canal waters are responsible for the recharge and waterlogging in the shingle clayey layers of the unconfined aquifer. High tritium data show that the aquifer system of the Peshawar valley area contains water recharged after 1953. This indicates that the residence times of waters are short possibly due to significant withdrawal of the aquifers which also enhances the recharge of precipitation as well as induced infilteration from canals. In general, high tritium contents are associated with very depleted stable isotopic contents of the water molecules. This in other words indicates that canal infilteration and possibly recharga of farm irrigation waters has significantly affected the isotopic composition of the shallow waters in the 9 unconfined aquifer. The isotope geochemical profiles based on soil soluble and adsorbed sulfate indicate significant variations in the 63*S at different locations in the valley. Higher *34S values are associated with unconfined aquifer being recharged by canals and local rains. The 634S values of the surface waters and the subsurface waters in the well irrigated areas of the unconfined aquifer are quite positive (0 %o to +6.3 %o CDT) as compared to those in the confined artesian aquifer (-7.1 %o to -0.1 %o CDT). This difference also indicates two different sources of sulfate in the aquifer system of the Peshawar valley area. The chemical quality of the shallow groundwater is quite poor as compared to that for the irrigation canals and the deep groundwaters. The higher salinity levels of the shallow groundwaters is attributed to the chemical reactions between recharging waters and the soil sediments, soil evaporation and evapotranspiration, use of fertilizers and the use of sodium chloride as bacterial disinfectant in the open wells. It is suggested that in the clayey aquifers of the Peshawar valley , the problem of waterlogging and salinization can be overcome by proper lining of the irrigation canal channels, by readjusting the delta for farm irrigation practice to reduce the recharge from farm irrigation and by abandoning the pumping wells penetrating to the artesian aquifer. 6. References Hussain, S.D., Sajjad, M.I., Akram, W., Ahmad, M., Rafiq, M. and Tariq, J.A., Surface water/Groundwater relationship in Chaj Doab, Pinstech/Riad-122, 1990. Mizutani,Y. and Rafter, T.A., Oxygen isotopic composition of sulphates, 5. Isotpic composition of sulphates in rain water, Gracefied, New Zealand. N.Z. J. Sci., 12(1969c)69-80. Mushtaq M., Waterlogging in the Rechna Doab:- A geographical study. The geological bulletin of the Punjab university- Pakistan. No. 20, (1965) 49-59. Fritz, P. and Fontes, J. ch., Handbook of Environmental Isotope Geochemistry, Vol.1, Elsevier Scientific Publishing Company, New York, 1980;pp 237. WAPDA., Project Report - Peshawar SCARP, Draft Publication No. 12, Water And Power Development Authority, Project Planning Organization (N.Z), Planning and Investigation Division,-27-E/l Gulberg III, Lahore, Pakistan (1973). 10 il!l*J*t.tl' < LU < o UJ 3 cz a_ u_ o a. < 2 o < o sV o t LU S N ,^l ^ S> • J***** \ >- LU d cc < txo UJ a. o O a. < CuO. o < o fSJ 1 UJ rr: z> o u. U) a. _l 2 Si WE L in -j 7. < •* UJ z a2: a < < a. < a a o <-> o o o y *** 6D(V„) 20 -20 -40 -60 X Precipitation data -80 — 8D-880l8->H[SargodaJ — SD-7.lSOl8*9.5[Reg.] -100 -14 -12 -10 -8 m -6 -4 0 18 18 8 0(%o) Fig. 3: 6 O vs 6D of All Monthly Averaged Rain Samples VK y •si*.& €D (%o) -20 - -40 •60 -80 3K Precipitation data 60-7.6*018*10.4 SD'8*018*13.4 -100 J i i J I I I I 1 L. -13 -12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0 S180 (%o) 18 Fig. 4: 8 O vs SD of Rain Samples of Peshawar City V -60 DEUTERIUM ( V..) -70 -80 -90 -11 — c OXYGEN-18 (V..) -12 - -13 -H i 1 1 1 1 1 ..J_ L_ , MJJASOND MONTHS FIGURED SEASONAL VARIATIONS OF18OAND2H IN THE IRRIGATION CANAL WATERS- \ r \ t *W5^** \ UJ UJ 3 CD 3 *U3 l/> > < *x I UJ cr O N < z < UJ _J < -J J Ul J d a ui »- w ? > N w £ < UJ z < z UJ g > z irt ui z 5 3 £ < < a. < 6 o. a u o o «-> f- ^ 8D (%o> -20 a ^a a .•» a iT • -40 ^ SF^ •" a >^a a y -80 a *>/• *y • 01/0 Wells -80 + C««*rf M«//« */^ ^ Canal* SD ' 8 * SOW * 14 -100 I . i i.. 1 I i i i i -14 -13 -12 -11 -10 -9 -8 -7 -6 -S -4 18 S 0(%0) ,18, Fig. 8: 8 O vs SD of Water Samples Collected in July, 1982 *** 6D (%o) -20 -40 y<9 y\ + • -60 m • 01/t? H%//« -80 + CMfd Wilt * CanalB 8D - « • 6OI0 • M -100 i " i ._ i . . i i i i -14 -13 -12 -11 -10 -9 -8 -7 -6 -5 -4 18 M S 0(%o) .18 Fig. 9: 8 O vs SD of Water Samples Collected in Nov. 1982 / w •sf'.&. 6D (%o) -20 -40 - •a." -60 4" y * • Dug Mfe//s -ao y^ ^ Canals — so - a • sor« • /* -10C i i i ' i 1 . i , ,.!... -/4 -fJ -12 -11 -10 -9 -8 -7 -6 -5 S O (%o) 13, Fig. 10: S O vs 3D of Water Samples Collected in June 1984 •ww .** SD (%o) -20 J^ -40 - -50 ~ • y/f + •ft' • a £71/0 Mfe//* -80 + (?««• S180 (%0> Fig. ii S18. O vs 80 of Water Samples (Mean Values) ^ i* 99.9 PRECIPITATION INDEX 99 / ARTESIAN VWVTEFL 95 MIXING WITH ARTESIAN WATER, U) o PREIRRIGATION UNCONPINED GROUNDWATER UJ 90 MIXING ZONE a Uj UJ > 50 20 5 o 5 1 0.1 _i L± L -12 -10 -8 -6 -4 6 0-18 (per mil. SMOW) FIG-12> NORMAL PROBABILIY PLOT OF 6 0-18 OF GROUNDWATER s Deep Qroundweter i—>- -t -i ~i 5 12 j— S P -1 2" BE-: .3 r. hrr iVi I ' 1 H 1 1 < * * ^ > i -12 -10 -8 SO-75 (%o) 8hmllow Groundwater 10 1 i ' — i — - • Tin •~ T- v-, ' 'V h- Hi "h.i r "i -12 -10 • -6 80-18 <%o) Deep A Shallow Groundwater 30 1 :i£ •-I 12 L. 1 r (••.••'••.I. ,••:.•• . . .. -i -i ! I- :;.:'-:'-::-l- ^#-:^*^ -i: 80-18 <*o) Fig. 13: Histograms of 80-18 of Groundwater **<*&** \ 1 / jaieMpunojQ uf umiiiji ;o IUBJBOISIH Aouanbajj :QI -dij Jmk. J~4. :>:>:: j_k UUi It. L.I, •Ixi. J 01 1 H—U* s uaJ ST .L oe. « '*fs- X»«V%W \ UJ o u* or Z) in UJ •— r> to in in % — in in m f? ^ OQ o z t ID UJ a: D i5 IS* < Z < O * UJ < VIL I a UJ i/> UJ UJ a n _) N. N UJ z < Z I in UJ z < UJ < < a. < o 3 a. a u o <-> —( xs&* LEGEND PROJECT BOUMfcRY RIVERS CANALS CASED WELLS OPEN WELLS CANAL SAMPLES TOWN/VILLAGE JUE.ZEROAD( CANAL) JZ FIGURE 17« SULFATE CONCENTRATIONSm) IN SURFACE AND SUBSURFACE WATERS- V V' S \ \ 3A S S (V..) (mg SO, /kg SOIL)* 100 A 12 -8 -A 0 A 0 10 20 30 AO 50 60 70 _i i i i i_ -J 1 I I L___J l_ 0 — -o 20 r AO 60 80 100- SOIL CORE N05 (TIRAHI PAYAN) 120 A 1A0 10 1A 18 22 26 30 0 A 8 12 16 20 i i i t i i i i i i i i o- ? 20- i ^ 4 A0- <> \ SOIL CORE NO-10 60- UDALA-ZAK RD- END) 80- > 100- r^ -2 2 6 10 1A 0 A 8 12 16 20 2A i i lit i i i i i i i 0- 20- A0- \S0IL CORE NO-20 i 60- >(KFD- BANDA) / 80- FIGURE-18- PROFILES OF CONCENTRATION OF SOIL EXTRACTED SULfftTE AND ITS34S COMPOSITIONS.