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: Bannu SCARP, Pakistan 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 Peshawar, Pakistan *2Transport Department, Government of Khyber Pakhtunkhwa, 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 Bannu Division, 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- 344 Int. Res. J. Agric. Sci. Soil Sci. 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 Marwat. 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 Lakki Marwat 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: Kot Kashmir, 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 Waziristan 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 Khyber Pakhtunkhwa Azad Kashm ir (a) Fa ta # Pun jab Balochistan Sin dh N (b) # 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 8.00 ECe(dS/m) 6.00 4.00 2.00 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 2.