Assessment and management of underground water quality in different land slopes of calcareous soils

Transcription

1 An Asian Journal of Soil Science Volume 7 Issue 2 December, 2012 A Case Study Assessment and management of underground water quality in different land slopes of calcareous soils MEMBERS OF RESEARCH FORUM : Corresponding author : H.P. PATEL, Department of Agricultural Chemistry and Soil Science, Junagadh Agricultural University, JUNAGADH (GUJARAT) INDIA hiren_agri36@yahoo.co.in Coauthors : S.G. SAVALIA, Directorate of Research, Junagadh Agricultural University, JUNAGADH (GUJARAT) INDIA sgsavalia@yahoo.co.in M.C. CHOPADA, Department of Agrometereology, Junagadh Agricultural University, JUNAGADH (GUJARAT) INDIA mcchopada@jau.in Received : ; Accepted : Summary A Case study was undertaken to attempt the assessment and management of underground water quality in different land slopes of calcareous soils (India). The underground water of open/tube wells situated at higher elevation have low ph, EC, water soluble Mg 2+,Na +, CO 3 2, HCO 3, Cl, SSP and SAR than in lower elevations. The SSP and SAR also increased with increase in EC and ph. The underground water from undulating upper pediment (typic ustothrents) as well as upper pediment (typic ustothrents) and lower pediment (Vertic Haplustepts) of calcareous soils were placed under safe class of C 2 and C 3, respectively. Whereas the alluvial plain (Calcic Haplustepts) and coastal plain (Fluventic Haplustepts) in doubtful class of C 4, respectively. In general, underground water samples from different land slopes of calcareous soils were placed under C 3 water quality class. Key words : Characterization, Assessment, Underground water quality, Calcareous soils, Land slopes, South Saurashtra, Gujarat How to cite this article : Patel, H.P., Savalia, S.G. and Chopada, M.C. (2012). Assessment and management of underground water quality in different land slopes of calcareous soils. Asian J. Soil Sci., 7(2):. Introduction Under ground waters in different land slopes of calcareous soils in southern Saurashtra region in Gujarat (India) have diversity of quality problems. Irrigation water of good quality is usually not available in sufficient quantities to satisfy the water requirement of crops in the southern Saurashtra region of Gujarat (India) as there are limited canal water facilities. Under these conditions, the farmers are obliged to use underground of water with high quantities of dissolved salts, invariably accompanied with yield reduction in most of the crops being grown. Indiscriminate use of such water often leads to crop failures and development of the saline or sodic soils, which are in turn, require expensive treatment to make them productive again. On the other hand judicious use of saline water can contribute to the sustainable production of various crops particularly in light textured welldrained soils. Attempts have been made in the present case study to assess quality of underground water in different land slopes of calcareous soils in Meghal Irrigation Command area of Southern Saurashtra in Gujarat (India) and to suggest management strategies. Resources and Research Methods The study area comprises of south Saurashtra agroclimatic zone covering major part of calcareous soils of Junagadh district in Southern Saurashtra region of Gujarat (India). It lies between to N latitude and to E longitude and 5 to 115 m above MSL. The area climatically falls under semiarid (dry) climate with a mean annual rainfall of 815 mm. The maximum, minimum and mean temperatures are 33.8 o C, 19.8 o C and o C, respectively. The temperature regime of the study area is hyperthermic in undulating upper pediment, upper pediment and lower pediment, while isohyperthermic in alluvial plain HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE

2 and coastal plain. The representative water balance of the study area is given in Fig. A. Out of the 80 open wells / bore wells underground water samples distributed in (Maliya and Veraval taluka of Junagadh district of calcareous soilzs having adjoining 16 water samples to each profiles in different land forms (Fig. B) viz., undulating upper pediment (Typic Ustothrents, LS1), upper pediment (Typic Ustothrents, LS2), lower pediment (vertic haplustepts, LS3), alluvial plain (Calcic Haplustepts, LS4) and coastal plain (Fluventic Haplustepts, LS5) were collected during month of May2009 from areas of Meghal Irrigation Command area of Southern Saurashtra of Gujarat (India) and analysed for ph, EC, cationic and anionic composition according to methods as out lined by Richards (1954). The underground waters were categorized for their classes according to the USSL staff (Richards, 1954). These guidelines are practical and usable, in general, for irrigation agriculture. The water quality guidelines suggested are intended to cover a wide range of conditions in irrigated agriculture and incorporate the newer concept in soilwaterplant relationship. (a) pedonsp 1, p 2, p 3, and p 4 (b) pedons p 5 Rainfall (mm) and pet (mm) Temp. ( 0 C) and 1/2 pet (mm) Rainfall (mm) and pet (mm) Temp. ( 0 C) and 1/2 pet (mm) Months Months Fig. A: Representative water balance diagrams of the study area Fig. B: Site of pedons in different land slopes of calcareous soils in Southern Saurashtra of Gujarat HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 397 Asian J. Soil Sci., (Dec., 2012) 7 (2) :

3 ASSESSMENT & MANAGEMENT OF UNDERGROUND WATER QUALITY IN DIFFERENT LAND SLOPES OF CALCAREOUS SOILS Research Findings and Discussion The experimental findings of the present study have been presented in the following sub heads: Characterization and classification of water resources : The range of chemical characteristics of calcareous soils irrigated with corresponding open wells/ tube wells is presented in Table 1. The soils of the study area are very shallow to deep, sandy loam to clay loam in texture, moderately alkaline in reaction and highly calcareous in nature (Table 1). Characterization of underground waters in different land slopes of calcareous soils in Meghal Irrigation Command area of Southern Saurashtra are reported in Table 2. The data on water table depth presented in (Table 2) reveal that the depth of water table ranged from 6 to 29 m with overall mean of 20 m. The depth of water table in different land slopes of calcareous soils observed in order of undulating upper pediment (29 m) (Typic Ustothrents) > upper pediment (Typic Ustothrents) and lower pediment (22 m) (Vertic Haplustepts) > alluvial plain (21 m) (Calcic Haplustepts) >coastal plain (6 m) (Fluventic Haplustepts). The availability of ground water was scarce and greater depth in undulating upper pediment (Typic Ustothrents) as compared to coastal plain (Fluventic Haplustepts). Besides the soil, water is a natural resource, which is essential for crop production. The semi arid region is dependent on irrigated agriculture underground waters in different land slopes of calcareous soils of southern Saurashtra have diversity of quality problems. Irrigation water of good quality is usually not available in sufficient quantities to satisfy Table 1 : Chemical characteristics of calcareous soils Irrigated with corresponding open wells/tube wells in representative pedons of different land slopes of calcareous soils (Weighted mean) Pedon and toposequence Depth (m) Clay (%) ph (1:2.5) EC (dsm 1 ) O.C. (%) CaCO 3 (%) CEC (cmol (p + ) kg 1 ) ESP LS1 Undulating upper pediment, MSL : 115 m, Typic Ustothrents P LS2 Upper pediment, MSL : 90 m, Typic Ustothrents LS3 Lower pediment, MSL : 45 m, Vertic Haplustepts LS4 Alluvial plain, MSL : 15 m, Calcic Haplustepts LS5 Coastal plain, MSL : 5 m, Fluventic Haplustepts Overall mean Table 2 : Chemical composition of irrigation water collected during month of may (mean of sixteen wells /bores adjoining to each profile) in different land slopes of calcareous soils EC Cations (mel 1 Total Pedon and Water table ) Anions (mel 1 Water ) ph (dsm toposequence depth (m) 1 ) cations SSP SAR quality at 25 0 C Ca 2+ Mg 2+ Na + K + (mel 1 2 ) CO 3 HCO 3 Cl class LS1 Undulating Upper Pediment, MSL : 115 m, Typic Ustothrents P C 2 LS2 Upper Pediment, MSL : 90 m, Typic Ustothrents C 2 LS3 Lower Pediment, MSL : 45 m, Vertic Haplustepts C 3 LS4 Alluvial Plain, MSL : 15 m, Calcic Haplustepts C 4 LS5 Coastal Plain, MSL : 5 m, Fluventic Haplustepts C 4 Overall mean C 3 Note: RSC found absent in all water samples HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 398 Asian J. Soil Sci., (Dec., 2012) 7 (2) :

4 the water requirement of all the crops grown in the Southern Saurashtra region as there are limited canal water facilities. Under these conditions, the farmers are obliged to use underground water with high quantities of dissolved salts, invariably accompanied with yield reduction in most of the crops being grown. Indiscriminate use of such water often leads to crop failures and development of the saline or sodic soils, which are in turn, require expensive treatment to make them productive again. On the other hand judicious use of saline water can contribute to the sustainable production of various crops particularly in light textured well drained soils. Overall underground water quality in different land slopes of calcareous soils : The data on depth of underground water table, ph, EC, water soluble cations (Ca 2+, Mg 2+, Na + and K + ) and anions (CO 3 2, HCO 3 and Cl ) of underground water from different wells/bores adjoining to pedons P 1 to in different land slopes of calcareous soils are presented in Table 2 and are discussed as under : The results reveal that the water table depth ranged from 6 to 29 m with the overall mean of 20 m. The depth of underground water table in different land slopes in calcareous soils was found in the order of undulating upper pediment Table 3 : Evaluation of underground water for irrigation based on combined effect of EC and SAR in different water quality class (based on semilogarithmic USSL diagram) in different land slopes of calcareous soils Water quality Pedon Well / Bore No. of Distribution Guideline for suitability and management class No. well Sr.No. Samples (%) C 2 P 1 C 3 P 1 C 4 P 1 C 4 P 1 1,2,3,4,7 to 15,16 17,19,20,22,23, 24,26 to ,6 18,21,25 33 to 41 and 43 to 48 49,50,52 59 to 64 65,75 51,53 to to 67, 69 to 74, 76 to ) Water can be used with moderate leaching HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 399 Asian J. Soil Sci., (Dec., 2012) 7 (2) : 2) Plants with moderate salt tolerance can be grown in most cases without special practices for salinity control. 3) Water can be used for all soils with little danger of harmful Na level development. 4) The Na sensitive crops might be affected ) Water cannot be used on soils with restricted drainage. Even with adequate drainage, special management for irrigated crops may be required. 2) Plants with good salt tolerance should be selected. 3) Water can be used for all soils with little danger of harmful Na level development. 4) The Na sensitive crops might be affected ) Water is not suitable for irrigation under ordinary conditions, but may be used occasionally under very special circumstance. The soil must be permeable, drainage must be adequate and irrigation water must be applied in excess to provide considerable leaching. 2) Very salt tolerant crops should be selected. 3) Water can be used for all soils with little danger of harmful Na level development. 4) The Na sensitive crops might be affected ) Water is not suitable for irrigation under ordinary conditions, but may be used occasionally under very special circumstance. The soil must be permeable, drainage must be adequate and irrigation water must be applied in excess to provide considerable leaching. 2) Very salt tolerant crops should be selected. 3) Sodium hazard likely occurred in fine textured soil. 4) Water can be used on soil having high permeability.

5 ASSESSMENT & MANAGEMENT OF UNDERGROUND WATER QUALITY IN DIFFERENT LAND SLOPES OF CALCAREOUS SOILS (Typic Ustothrents) > upper pediment (Typic Ustothrents) = lower pediment (Vertic Haplustepts) > alluvial plain (Calcic Haplustepts) > coastal plain (Fluventic Haplustepts). It is observed that the availability of ground water was scare and at greater depth in undulating upper pediment (Typic Ustothrents) as compared to coastal plain (Fluventic Haplustepts). The ph of underground water of well / bores of different land slopes in calcareous soils ranged between 8.06 and 8.17 with the overall mean of The EC ranged between 0.64 and 6.90 dsm 1 with the overall mean of 2.50 dsm 1 (Table 2). The ph and EC increased with decreasing elevation from undulating upper pediment to coastal plain of calcareous soils (Fig. 1). This can be ascribed to the accumulation of soluble salts at the lower elevation carried by the percolating water. Undulating upper pediment Upper pediment Lower pediment Alluvial plain Coastal plain Fig. 1 : Variations in ph, EC and SAR of the underground water of different land slopes in calcareous soils Out of the 80 wells / bores underground water samples, only 29 samples (Table 3)were placed under very high (C 4 ) salinity water class as per the limits outlined by Richards (1954). Similar, results were also reported by Singh et al. (1967), DACS (1988) and Savalia et al., (2006). Among the cations, Na + was dominant in different land slopes of calcareous soils varied from 1.37 to 14.7 me l 1 followed by Mg 2+, Ca 2+ and K + with a range of 2.23 to 12.9, 3.56 to 7.70 and 0.03 to 1.40 mel 1, respectively. The corresponding mean values of these cations were 5.91, 5.74, 5.51 and 0.33 me l 1 (Table 2). The total water soluble cations ranged from 7.18 to me l 1 with a mean value of me l 1, which increased with decreasing elevation from 7.18 me l 1 in the undulating upper pediment to me l 1 at coastal plain (Table 2). Similar results were also reported by Savalia et al. (2006). The concentration of Ca 2+ and Na + increased with an increase in EC (Gupta, 1986 and Savaliaet al., 2006). Among the anions, CO 3 2, HCO 3 and Cl ranged from 0.00 to 1.20, 3.30 to 5.50 and 2.10 to me l 1 with the mean values of 0.69, 4.27 and me l 1, respectively (Table 2). The HCO 3 was the dominant anion followed by Cl in undulating upper pediment and upper pediment whereas the Cl was dominant followed by HCO 3 in lower pediment to coastal plain (Table 2). Similar observations have been made by Savalia et al. (2006). The total water soluble cations as well as anions were highest in coastal plain (Fluventic Haplustepts). This might be due to the ingress of sea water (Patel et al., 1982) caused as a result of over exploitation of groundwater for irrigation, in areas near to the sea. The SSP of irrigation water ranged from to me l 1 with a mean value of me l 1 indicating the irrigation water is not harmful (< 60 SSP) with respect to Na + ion. The SAR of underground water ranged from 0.81 to 4.57 with a mean value of 2.14 indicating the irrigation water of different land slopes in calcareous soils have low sodium hazard. The SAR and SSP increased with increasing ph and EC (Savalia et al., 2006). The RSC was absent in all water samples. These results are in conformity to those reported by Savalia (2005). The results indicated that the continuous and indiscriminate use of such underground water is expected to buildup excessive sodium in soil solution and an exchange complex and will also clog the soil pores, which may lead to drainage problems in lower elevation (Table 1). These results are in conformity to those reported by Sood et al. (1998). Assessment and management of underground water quality: The evaluation of underground water was carried out based on combined effect of EC and SAR classes. As per the limits proposed by USSL staff (Richard, 1954), the underground water from undulating upper pediment as well as upper pediment (Typic Ustothrents) and lower pediment (Vertic Haplustepts) of calcareous soils were placed under safe class of C 2 and C 3 whereas the alluvial plain (Calcic Haplustepts) and coastal plain (Fluventic Haplustepts) in doubtful class of C 4, respectively. In general, underground water samples from different land slopes of calcareous soils were placed under C 3 water quality class (Table 2). Out of 80 well / bore, water samples from different land slopes of calcareous soils, only twenty one water samples from alluvial plain to coastal plain were poor in quality C 4 andc 4 class, respectively as per the limit outlined by Richards (1954). The per cent distribution of underground water for irrigation of the different land slopes of calcareous soils (based on semilogarithmic USSL diagrams) are presented in Table 3. The results reveal that out of 80 wells/tube wells water samples, 35.0, 28.8, 10.0 and 26.2 per cent were placed in C 2, C 3, C 4 water quality class, respectively. The guideline for its suitability and management are given in Table 3. The guidelines for suitability and management of different water samples adjoining to respective pedons of different land slopes of calcareous soils are discussed in Table 3. The different quality of irrigation water is not suitable directly to the particular location. It is just guideline for use as irrigation purpose. HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 400 Asian J. Soil Sci., (Dec., 2012) 7 (2) :

6 Conclusion: From the above discussion, it appears that physiographic position is definitely affected in underground water quality. The ph, EC, total water soluble cations and anions, SSP and SAR of underground water were higher in lower elevated area as compared to higher elevated area. The underground water of open wells/tube wells situated in alluvial plain (Calcic Haplustepts) and coastal plain (Fluventic Haplustepts) were placed under doubtful class of C 4 water quality, respectively. The guideline for its suitability and management strategy are also discussed in the text. Literature Cited DACS (1988). Annual Research Report. Department of Agricultural Chemistry and Soil Science, Gujarat Agricultural University, Junagadh (GUJARAT) INDIA. Gupta, T. C. (1986). Quality of irrigation water recent criteria and classification. Curr. Agric., 10: 115. Patel, M.S., Kanzaria, M.V., Qureshi, A.U., Patel, C.L. and Hadiyal, T.M. (1982). Irrigation water quality of coastal and interior area in Saurashtra region of Gujarat. Proceeding, Seminar on the Management of Saline and Alkali Soil in Gujarat held at April, 1982 at Gujarat Agricultural University, Junagadh (GUJARAT) INDIA. pp Richards, L. A. (1954). Diagnosis and improvement of saline and alkali soils. USDA Hand Book No. 60. Government Printing Office, Washington, D.C., USA. Singh, K. S., Lal, P. and Lal, F. (1967). Preliminary studies on the effect of irrigation waters on the properties of soils of Jobner tract, Jaipur, Rajasthan. J. Indian Soc. Soil Sci., 15: Savalia, S. G. (2005). Characterization, classification and evaluation of soil and water resources across the toposequences of Southern Saurashtra. Ph.D. Thesis, Junagadh Agricultural University, Junagadh, GUJARAT (INDIA). Savalia, S.G., Gundalia, J.D. and Mathukiya, R.K. (2006). Assessment and management of underground water quality in different land slopes of South Saurashtra (Gujarat). Internat. J. Tropical Agric., 24(12): Sood, A., Verma, V.K., Thomas, A., Sharma, P.K. and Brar, J.S. (1998). Assessment and management of underground water quality in Talwandi Sabo Tehsil of Bathinda District (Punjab). J.Indian Soc. Soil Sci., 46: ******** ****** **** HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 401 Asian J. Soil Sci., (Dec., 2012) 7 (2) :