International Research Journal of Agricultural Science and Soil Science (ISSN: 2251-0044) Vol. 3(10) pp. 343-352, October, 2013 DOI: http:/dx.doi.org/10.14303/irjas.2013.109 Available online http://www.interesjournals.org/IRJAS Copyright ©2013 International Research Journals

Full Length Research Paper

Evaluation of salinity and sodicity parameters: SCARP,

Mahmood Alam Khan 1, Taj Ali Khan 1, Muhammad Shahzad Khan 1, Tariq Usman Saeed 2* , Daulat Khan 1

1Department of Agricultural Engineering, University of Engineering and Technology , Pakistan *2Transport Department, Government of , Peshawar Pakistan

*Corresponding author`s e-mail: [email protected]

ABSTRACT

Th e research article evaluates the soil s alinity and sodicity levels in the area stuck by water logging and salinity. Soil Sampling was done in the SCARP area of , Khyber Pakhtunkhwa province of Pakistan between December 2010 to March 2011 and tests were performed in Environmental Engineering Lab at Department of Agricultural Engineering, University of Engineering and Technology, Peshawar Pakistan. For this purpose twenty three sampling points were randomly selected and samplings were made at three different depths ranging from 0-0.25, 0.25-0.5 and 0.5 to 1 meter. Soil samples were analyzed and results were prepared for parameters like Electrical Conductivity of Soil Saturate Extract, Na +, Ca ++ , Mg ++ , K +, -- - - CO 3 , HCO 3 , Cl , SAR and RSC. The average value of EC e was 5.69 dS/m which revealed that the + ++ ++ + -- - - soil is saline in nature. The average concentration of Na , Ca , Mg , K , CO 3 , HCO 3 , Cl , SAR and RSC were determined as 2.87 meq/l, 0.28 meq/l, 0.08 meq/l, 1.14 meq/l, 0.78 meq/l, 2.25 meq/l, 18.12 meq/l, 8.46 and 2.67 meq/l respectively. The average values of EC e and SAR are 5.69 dS/m and 8.46 respectively. Based on these findings, the soil of the study area is classified as saline. The average RSC value of the soil is 2.67 meq/l. These average RSC values indicate that concentrations of carbonates and bi-carbonates are high, which cause calcium and magnesium to precipitate in the soil. The results suggested that the study area is facing an acute concentration of soluble salts and reclamation measures are needed to bring this area under cultivation. Irrigation water quality analysis, reclamation of soil and provision of proper drainage system are recommended.

Keywords : Soil salinity; Sodicity; Anions; Cations; Standard Deviation; Coefficient of Variation; SCARP (Salinity Control and Reclamation Project)

INTRODUCTION

Soils with high amounts of soluble salts are called saline physical restrictions to plant growth. Sodium (Na +) is a soils. They often exhibit a whitish surface crust when dry. positively charged component, or cation, of many salts. The solubility of calcium sulphate or gypsum (CaSO 4) is Sodium problems are due to its behavior when attached used as the standard for comparing solubilities of salts. to clay particles. If 15 percent or more of the clay Salts more soluble than gypsum are considered to be adsorption sites are occupied by sodium (sodium-clay), soluble and cause salinity. Examples are sodium poor physical condition of the soil often restricts root sulphate or Glauber’s salt (Na 2SO 4) and sodium chloride, growth and makes tillage difficult (Seelig, 2000). Rise in or table-salt (NaCl). Salts less soluble than gypsum are water table levels contributes significantly to considered insoluble and do not cause salinity. Calcium salinity/sodicity development (Khan and Akram, 1986). carbonate (CaCO 3) or lime is an example of an insoluble Increasing soil salinity is a serious land degradation salt. Soils high in sodium (sodic soils) may present issue, with the area affected by dry land salinity esti-

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mated to be approximately 4 million ha in 2000, and is and sub-tropical continental. The soils are used for dry predicted to increase to 20 million ha by 2020 (National farming and torrent water cultivation (Population Census Land and Water Resources Audit (NLWRA). Agriculture- Organization, Statistics Division of Pakistan. District induced salinity and sodicity not only influences the Census Report of Lakki . 2000). There are two chemical and physical characteristics of soils but also main sources of irrigations, Kurram and Gambila Rivers. greatly affects soil microbial and biochemical properties Kurram and Gambila rivers provide surface irrigation by (Rietz and Haynes, 2003). Soil salinization is one of the canal systems, while ground water is lifted by installing major factors that contribute to land degradation and tube wells. decrease in crop yield (Anjum et al., 2005). It was The study area suffers severely from waterlogging and reported that salinity in the arid and semi-arid regions of salinity. Texture of the soil varied from clay loams, silty the world is a serious threat to agriculture (Rao et al., and fine sandy clay loams. The main factors contributing 2002). Production of grain legumes is severely reduced in to waterlogging problem are: seepage from canals, salt-affected soils because their ability to form and inequity in the civil canal system (due to existing and maintain nitrogen fixing nodules is impaired by both prevailing system of water distribution), unawareness of salinity and sodicity (alkalinity). (Shah and Shah, 2011) farmers of the area about irrigation scheduling and found that salinity is usually combined with high pH unavoidable losses from the irrigation system. The area conditions, due to the presence and enrichment of is facing an acute problem of soil salinity and the levels of calcium carbonate in the upper most soil layers in the arid soil salinity in this area are needed to be identified. The and semi-arid regions of Pakistan. (Khattak et al., 2002) specific objectives of the study area include; investigation evaluated the impacts of groundwater on soil and crops of major cations and anions, and determination of soil in District Karak (arid region). Soil deterioration and salinity and sodicity levels (ECe, SAR and RSC) in Zone reduction in crop yield were noted due to water – A of Bannu SCARP. salinization. Tavakkoli et al. 2010 concluded that multiple factors contributing to subsoil constraints include salinity, sodicity, and high concentrations of chloride which are METHODOLOGY present in many rain-fed farming soils of Southern Australia. Moradi and Abdelbagi 2007 found that salinity This study was conducted from December 2010 to March is a widespread soil problem limiting productivity of cereal 2011, in which soil samples were collected and then crops worldwide. analyzed for salinity and sodicity status of the study area. The project area was surveyed and twenty-three (23) sampling points were selected randomly. From each Study Area sampling point at three different depths (0 – 0.25, 0.25 – 0.50 and 0.50 – 1m) soil samples were taken with the This area lies between 32.70 o to 32.78 o N latitude and help of auger. Thus total of sixty nine (69) soil samples 70.70 o to 70.72 o E longitude with central coordinates of were collected from the whole study area (Figure-1). All 32.73 o N and 70.71 o E. Zone-A of Bannu SCARP is the soil samples were carefully taken to the laboratory in situated in district of Khyber Pakhtunkhwa, plastic bags for its various characteristics following Pakistan, about 180 km south of Peshawar, comprising methods described by Richards, 1959. an area of about 3241 ha with total perimeter of 25.37 km (Figure 1). This zone suffers a very severe water logging and salinity problem. Main villages in Zone-A of Bannu RESULTS AND DISCUSSION SCARP are: , Gandi Khan Khel, Pahar Khel and Serai Gambila (National Drainage Program (NDP) The analysis results have been presented in Figures 2 to PC-I Proforma, Bannu SCARP-II, NWFP Pakistan. 2002). 11. Figure 1 shows the study area and sampling locations.

Geology and Hydrogeology Electrical conductivity of the soil extract

Main constituents of soil in district Lakki Marwat are deep Figure 2 shows average EC e concentrations of the soil at excessively drained calcareous and coarse textured each sampling location. Soil samples taken from 0 – 0.25 (sand and loamy sand) developed from the silwalik sand m depth at different locations had an average EC e value stone of Shin Ghar and Marwat range piedmont material. of 6.15 dS/m, standard deviation of 2.84 dS/m and The fine textured soils (sandy clay and clay loam) of the coefficient of variation of 46.30%. The average value of area are developed from mixed material derived from EC e of soil samples taken from depths 0.25 – 0.50 m was variety of rocks of Bhittani and ranges. The 5.74 dS/m, standard deviation of 2.6 dS/m and coefficient soils occur on leveled to nearly leveled position in of variation of 45.40%. Similarly, the average value of piedmont plains. Climate of the area is arid to semi-arid EC e of the soil samples taken from 0.50 – 1 m depth was

Khan et al. 345

Gilgit Baltista n

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Azad Kashm ir (a) Fa ta #

Pun jab

Balochistan

Sin dh

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# LM 15 # LM 7 # LM 16 LM 17 LM 5 # # LM 6 # LM 4 # LM 2 # LM 3 LM 19 # # LM 18 LM 1 # # LM 20 #

LM 10 #

LM 23 LM 21 Drain # # Cannal LM 12 LM 8 LM 11 Road # ## LM 9 # # Sampling point # Boundary LM 13 LM 22 # LM 14 #

2 0 2 4Kilometers

Figure 1. (a) Map of Pakistan and (b) Study area showing sampling locations

14.00 ECe ECe Avg 12.00

10.00

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0.00 LM1 LM2 LM3 LM4 LM5 LM6 LM7 LM8 LM9 LM10 LM11 LM12 LM13 LM14 LM15 LM16 LM17 LM18 LM19 LM20 LM21 LM22 LM23 Sampling Location

Figure 2. Electrical Conductivity of the soil at various locations

346 Int. Res. J. Agric. Sci. Soil Sci.

5.00 Na Na Avg 4.50

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Figure 3. Sodium concentration of the soil at various locations

5.18 dS/m, standard deviation of 2.55 dS/m and depth was 2.86 meq/l, standard deviation of 0.73 meq/l coefficient of variation of 49.30%. The average values and coefficient of variation of 25.54%. The overall also indicated that salts were high in the upper soil layers average sodium concentration of the soil was 2.87 meq/l. as compared to the lower soil layers. Results reveal that soil salinity was decreased from top to bottoms. The overall average value of EC e has been 5.69 dS/m. Calcium concentration of the soil extract Richards, 1959 reports that soils having EC e greater than 15 dS/m are strongly saline. James et al. 1982 reported Graphical presentation of average calcium concentration that the soils having EC e greater than 4 dS/m are of the soil samples at each sampling location can be classified as saline soils. seen in Figure 4. Calcium concentration for the soil samples taken from 0 - 0.25 m depths, had an average value of 0.35 meq/l, standard deviation of 0.20 meq/l and Soluble cations of soil extract coefficient of variation of 57.18%. Average value of calcium concentration of the soil samples taken from 0.25 The most common cations of soils determined in the – 0.50 m depth was 0.26 meq/l, standard deviation of laboratories were Sodium, Calcium, Magnesium, and 0.19 meq/l and coefficient of variation of 76%. The Potassium. average concentration of calcium of the soil samples taken from 0.50 – 1 m depth was 0.23 meq/l, standard Sodium concentration of the soil extract deviation of 0.17 meq/l and coefficient of variation of 74.40%. The average value of all the depths reveals that Average sodium concentrations of the soil at each calcium content decreased with depths. The overall sampling location are presented in Figure 3. Sodium average value of calcium remained as 0.28 meq/l. concentration of the soil samples, which were taken from 0 - 0.25 m depths had an average value of 2.86 meq/l, Magnesium concentration of the soil extract standard deviation of 0.84 meq/l and coefficient of variation of 29.31%. Average value of sodium Figure 5 shows average concentration of magnesium of concentration from 0.25 – 0.50 m depth was 2.91 meq/l, soil samples at each sampling location. Soil samples, standard deviation of 0.72 meq/l and coefficient of taken from 0 - 0.25 m depths, had an average variation of 24.96%. Similarly average value of sodium magnesium concentration of 0.08 meq/l, standard concentration of the soil samples taken from 0.50 – 1 m deviation of 0.05 meq/l and coefficient of variation of

Khan et al. 347

0.60 Ca Ca Avg

0.50

0.40

0.30 Ca (meq/l)

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0.00 LM1 LM2 LM3 LM4 LM5 LM6 LM7 LM8 LM9 LM10 LM11 LM12 LM13 LM14 LM15 LM16 LM17 LM18 LM19 LM20 LM21 LM22 LM23 Sampling Location

Figure 4. Calcium concentration of the soil at various locations

0.18 Mg Mg Avg 0.16

0.14

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0.06

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Figure 5. Magnesium concentration of the soil at various locations

61.70%. The average magnesium concentration of soil Potassium concentration of the soil extract samples taken from 0.25 - 0.5 m depths was 0.08 meq/l, standard deviation of 0.05 meq/l and coefficient of The average potassium concentration of the soil samples variation of 57.65%. The average value of magnesium at each sampling location has been shown in Figure 6. concentration of the soil sample from 0.50 – 1 m depths Soil samples taken from 0 - 0.25 m depths, had an was 0.07 meq/l with standard deviation of 0.03 meq/l and average value of potassium was 1.34 meq/l, standard coefficient of variation of 47.70%. The average values for deviation of 0.57 meq/l and coefficient of variation all depths show that magnesium content remained almost 43.01%. The average values of potassium concentration same with depth. Its overall average value remained as of soil samples taken from 0.25 - 0.50 m depth, was 1.11 0.08 meq/l. meq/l, standard deviation of 0.45 meq/l and coefficient of

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2.50 K K Avg

2.00

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0.50

0.00 LM1 LM2 LM3 LM4 LM5 LM6 LM7 LM8 LM9 LM10 LM11 LM12 LM13 LM14 LM15 LM16 LM17 LM18 LM19 LM20 LM21 LM22 LM23 Sampling Location

Figure 6. Potassium concentration of the soil at various locations

16.00 SAR SAR Avg 14.00

12.00

10.00

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Figure 7. Sodium Adsorption Ration of the soil at various locations

variation of 40.95%. The average values of potassium Sodium absorption ratio (SAR) of the soil extract concentration of the soil samples taken from 0.50 – 1 m depths, was 0.97 meq/l with standard deviation of 0.44 Average SAR levels of the soil samples at each sampling meq/l and coefficient of variation of 45.10%. The average location can be seen in Figure 6. Soil samples taken from values reveal that potassium content decreased with depths of 0 - 0.25 m, had an average value of SAR as depths from 1.34 to 0.97 meq/l. The 0.50 – 1 m depth 7.77, standard deviation of 5.34 and coefficient of results show that the soil has low content of potassium in variation of 68.70%. The average value of SAR of the the lower depths. The overall average value of Potassium soil samples taken from 0.25 - 0.50 m depths, was 8.63, concentration was 1.14 meq/l.

Khan et al. 349

2.50 CO3 CO3 Avg

2.00

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1.00 CO3 (meq/l)

0.50

0.00 LM1 LM2 LM3 LM4 LM5 LM6 LM7 LM8 LM9 LM10 LM11 LM12 LM13 LM14 LM15 LM16 LM17 LM18 LM19 LM20 LM21 LM22 LM23 Sampling Location

Figure 8. Carbonate concentration of the soil at various locations

standard deviation of 3.98 and coefficient of variation of deviation of 0.84 meq/l and coefficient of variation of 46.10%. The average values of soil samples taken from 99%. The overall average concentration of carbonate of 0.50 – 1 m depth was 8.99, standard deviation of 4.49, the soil samples was 0.78 meq/l. and coefficient of variation of 50.10%. The overall average value for SAR was 8.46. James et al. 1982 Bicarbonate concentration of the soil extract reveals that soils with EC e greater than 4 dS/m and SAR less than 13 can be classified as saline soil. The average Figure 9 shows the average concentration of values reveal that SAR for all soil depths had increased bicarbonates of the soil samples at each sampling from top to lower soil layers. Soil investigation division of location. The average bicarbonate concentration of the WAPDA (Water and Power Development Authority soil samples, taken from 0 - 0.25 m depth had an (WAPDA) reported that SAR of all soils either decreases average value of bicarbonate as 2.34 meq/l, standard or remains unchanged, when irrigated with water having deviation of 0.86 meq/l and coefficient of variation of EC w of 1.5 dS /m, SAR less than 10 and RSC more than 36.80%. The average value of bicarbonate concentration 5.0 meq/l. of soil samples taken from 0.25 - 0.50 m depths was 2.26 meq/l, standard deviation of 1.23 meq/l and coefficient of variation of 54.60%. The average concentration of Soluble anions of the soil extract bicarbonate of the soil samples taken from 0.50 – 1 m depths was 2.17 meq/l, standard deviation of 0.89 meq/l The most common anions of soil determined in the and coefficient of variation of 41%. The overall average laboratories were Carbonate, Bicarbonate and Chloride. value of bicarbonate was 2.25 meq/l.

Carbonate concentration of the soil extract Chloride concentration of the soil extract

Average concentration of carbonates of the soil samples The average chloride concentration of the soil samples at at each sampling location of the study area are seen in each sampling location has been shown in Figure 10. Figure 8. The average carbonates concentration of the The average chloride concentration of the soil samples, soil samples, taken from 0 - 0.25 m depths had an taken from 0 - 0.25 m depth had an average value of average value of 0.78 meq/l, standard deviation 0.53 21.69 meq/l, standard deviation of 17.52 meq/l and meq/l and coefficient of variation 68%. The average value coefficient of variation of 80.75%. The average chloride of carbonates of the soil samples taken from 0.25 - 0.50 concentration of soil samples taken from 0.25 - 0.5 m m depths was 0.69 meq/l, standard deviation of 0.47 depths was 18.11 meq/l, standard deviation of 14.53 meq/l and coefficient of variation of 67.60%. The meq/l and coefficient of variation of 80.20%. Similarly average concentration of carbonate of the soil samples average value of chloride concentration of the soil taken from 0.50 – 1 m depth was 0.85 meq/l, standard samples taken from 0.50 – 1 m depths was 14.53 meq/l,

350 Int. Res. J. Agric. Sci. Soil Sci.

4.50 HCO3 HCO3 Avg 4.00

3.50

3.00

2.50

2.00 HCO3 (meq/l) HCO3 1.50

1.00

0.50

0.00 LM1 LM2 LM3 LM4 LM5 LM6 LM7 LM8 LM9 LM10 LM11 LM12 LM13 LM14 LM15 LM16 LM17 LM18 LM19 LM20 LM21 LM22 LM23 Sampling Location

Figure 9. Bicarbonate concentration of the soil at various locations

60.00 Cl Cl Avg

50.00

40.00

30.00 Cl (meq/l) Cl

20.00

10.00

0.00 LM1 LM2 LM3 LM4 LM5 LM6 LM7 LM8 LM9 LM10 LM11 LM12 LM13 LM14 LM15 LM16 LM17 LM18 LM19 LM20 LM21 LM22 LM23 Sampling Location

Figure 10. Chloride concentration of the soil at various locations

standard deviation of 10.19 meq/l and coefficient of location of the study area. The average value of RSC of variation of 70.09%. The average values of all the depths the soil samples, taken from 0 - 0.25 m depths had an reveal that chloride contents had increased with depth. average value of 2.68 meq/l, standard deviation of 1.31 The overall average value of chloride concentration was meq/l and coefficient of variation of 48.60 %. The 18.12 meq/l. average RSC values of the soil samples taken from 0.25 - 0.5 m depth, was 2.62 meq/l, standard deviation of 1.66 Residual sodium carbonate (RSC) level of the soil meq/l and coefficient of variation of 63.58 %. The extract average RSC value of soil samples from 0.50 – 1 m depths was 2.73 meq/l, standard deviation of 1.32 meq/l Figure 11 shows average values of Residual Sodium and coefficient of variation of 48.50%. The average Carbonate (RSC) of the soil samples at each sampling values of all the soil samples taken from 0.25 – 1 m

Khan et al. 351

5.00 RSC RSC Avg 4.50

4.00

3.50

3.00

2.50

2.00 RSC (meq/l) RSC

1.50

1.00

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0.00 LM1 LM2 LM3 LM4 LM5 LM6 LM7 LM8 LM9 LM10 LM11 LM12 LM13 LM14 LM15 LM16 LM17 LM18 LM19 LM20 LM21 LM22 LM23 Sampling Location

Figure 11. Residual Sodium Carbonate concentration of the soil at various locations

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Tavakkoli E, Jones B, Coventry S, Rengasamy P, McDonald G (2002). How to cite this article: Khan MA, Khan TA, Khan MS, Saeed TU, On-farm Assessment of Sub-soil Salinity and Sodicity Constraints to Khan D (2013). Evaluation of salinity and sodicity parameters: Barley Production in Southern Australia. Proceedings of 15th Bannu SCARP, Pakistan. Int. Res. J. Agric. Sci. Soil Sci. 3(10):343- Agronomy Conference 2010, 15-18 November 2010, Lincoln, New 352 Zealand. Accessed on: 09/04/2013 Water and Power Development Authority (WAPDA). Water Quality and Soil. A note on Soil Studies. Monitoring and Planning Organization, WAPDA Pakistan. 1974.