H. S. Hundal

Occurrence and Geochemistry of Arsenic in Groundwater of Punjab, Northwest India

Abstract Arsenic (As) is a deadly poison at high concentrations. It is mysterious in the sense that people are exposed to it most of the time through drinking groundwater, fortunately at much lower concentrations than the deadly levels, and usually without knowing it. Arsenic content in alluvial aquifers of Punjab varied from 3.5 to 688 µg L−1. Arsenic status of groundwater is classified into low (<10 µg L−1), moderate (≥10 to <25 µg L−1), high (≥25 to <50 µg L−1), and very high (>50 µg L−1). In zone I, the concentration of As in groundwater varied from 3.5 to 42 µg L−1 with a mean value of 23.4 µg L−1. On the basis of these limits, only 8% of samples were low, whereas 51 and 41% of the total samples collected from this region fall in the moderate and high As categories. The concentration of As in groundwater of zone II varied from 9.8 to 42.5 µg L−1 with a mean value of 24.1 µg L−1. Arsenic concentration in the alluvial aquifers of the central plain of zone II is 2 and 52% in the low and moderate limits. In this region, 46% of groundwater sites contain high As concentrations. Arsenic concentrations in the aridic southwestern parts are significantly different from other two provinces. The As concentration ranged from 11.4 to 688 µg L−1 with average value of 76.8 µg L−1. Eleven percent of the aquifers of the southwestern region of zone III are in the moderate category, 54% in the high, and 35% in the very high. According to safe As limits (<10 µg L−1), only 3 and 1% of the groundwater samples collected from zones I and II were fit for dinking purposes with respect to As content. In the aridic southwest, zone III, all water samples contained As concentrations greater than the safe limits and thus are not suitable for drinking purposes. The presence of elevated As concentrations in groundwater are generally due to the results of natural occurrences of As in the aquifer materials. The concentration of other competitive oxyanions in waters such as phosphate, sulfate, and borate also depressed the adsorption of As on the sorption sites of aquifer materials and thereby eventually elevate the As concentration in groundwaters. In groundwater of alluvial aquifers of Punjab, released from sulfide oxidation and oxyhydroxide of iron, elevated (>10 µg L−1) concentrations of As were widespread because of high pH (>8.0) and higher concentrations of phosphate, borate, sulfate, and hydroxyl anions. It is conclusively evident that geochemical conditions, such as pH, oxidation–reduction, associated or competing ions, and evaporative environments have significant effects on As concentration in groundwater. These conditions influence how much As is dissolved or precipitated into the water and how much is bound to the aquifer materials or the solid particles in water.

Monitoring Nutrient Status of Guava Fruit Trees in Punjab, Northwest India through the Diagnostic and Recommendation Integrated System Approach

Abstract The Diagnostic and Recommendation Integrated System (DRIS) was employed for interpreting nutrient analyses of leaf tissue of guava fruit trees (Psidium guajava L.) cultivated in Punjab, northwest India. Standard reference DRIS norms were established for various nutrient ratios and used to compute DRIS indices, which assessed nutrient balance and order of limitation to yield. The DRIS evaluation and sufficiency range approach were equally effective and in agreement for diagnosing deficiencies of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), sulfur (S), manganese (Mn), zinc (Zn), and copper (Cu). The results also show that the position of leaf tissue sampled does not have a major effect on the DRIS diagnosis. Nutrient sufficiency ranges derived from DRIS norms were 1.41–1.65, 0.10–0.17, 0.51–0.97, 1.16–2.12, 0.31–0.51, 0.18–0.28% for N, P, K, Ca, magnesium (Mg), and S and were 105–153, 58–110, 15–29, and 6–16 mg Kg−1 for iron (Fe), Mn, Zn, and Cu, respectively. According to these sufficiency ranges 35, 62, 51, 75, 70, and 68% of samples were sufficient, and 4, 29, 36, 9, 10, and 22% of samples were low in N, P, K, Ca, Mg, and S, respectively. More than 50 and 2% of the guava trees selected for sampling was found to deficient in N and P, respectively. For micronutrients, 15, 6, and 7% of samples were found to be low in Mn, Zn, and Cu.

Diagnosis and recommendation integrated system for monitoring nutrient status of mango trees in submountainous area of Punjab, India

Abstract The Diagnosis and Recommendation Integrated System (DRIS) was used to identify nutrient status of mango fruit trees in Punjab, India. Standard norms established from the nutrient survey of mango fruit trees were 1.144, 0.126, 0.327, 2.587, 0.263, 0.141% for nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S), and 15, 3.5, 145, 155, and 30 mg kg−1, respectively, for zinc (Zn), copper (Cu), iron (Fe), manganese (Mn), and boron (B) in dry matter. On the basis of DRIS indices, 16, 15, 12, 17, and 16% of total samples collected during nutrients survey of mango trees were low in N, P, K, Ca, and Mg, respectively. For micronutrients, 19, 18, 12, 20, and 6% samples were inadequate in Zn, Cu, Fe, Mn, and B, respectively. DRIS‐derived sufficiency ranges from nutrient indexing survey were 0.92–1.37, 0.08–0.16, 0.21–0.44, 1.71–3.47, 0.15–0.37, and 0.09–0.19% for N, P, K, Ca, Mg, and S and 11–19, 1–6, 63–227, 87–223, and 16–44 mg kg−1 for Zn, Cu, Fe, Mn, and B, respectively.

DIAGNOSIS AND RECOMMENDATION INTEGRATED SYSTEM (DRIS) FOR EVALUATING NUTRIENT STATUS OF COTTON (GOSSIPIUM HIRSUTUM)

Diagnosis and Recommendation Integrated System (DRIS) approach was employed to monitor the nutrient status of cotton (Gossipium hirsutum) in southwestern districts of Punjab, North-West India. DRIS norms for macro, secondary and micro nutrients in cotton plant are developed. Considering these DRIS norms, the most limiting nutrient for cotton plant in the region is identified along with the order in which the other nutrients become limiting. The DRIS approach indicated that 11, 3, 8, 5, 2, 4, 2, 3, 6 and 2 percent of the total cotton leaf samples collected were low in nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu), respectively. Leaf tissues of cotton plant were also found to contain high to excessive content of N, P, K, Ca, Mg, S, Fe, Mn Zn and Cu in 11, 7, 15, 19, 25, 18, 66, 33, 9 and 25 percent samples, respectively. DRIS derived sufficiency concentration ranges obtained from survey of cotton fields in this region were 2.22 to 5.20% N, 0.20 to 0.47% P, 1.05 to 2.14% K, 1.66 to 2.86% Ca, 0.34 to 0.57% Mg, 0.65 to 1.11% S, 106 to 172 mg kg−1 Fe, 35 to 68 mg kg−1 Mn, 18 to 33 mg kg−1 Zn, and 5 to 8 mg kg−1 Cu. The results elucidate that DRIS technique can be used for macro, secondary and micro nutrients indexing of cotton crop irrespective of its cultivar.

Adsorption of Arsenate on Coarse Loamy Mixed Hyperthermic Fluventic Haplustept Soil of Punjab, Northwest India

A laboratory experiment studied the adsorption of arsenate on coarse loamy mixed hyperthermic Fluventic Haplustept soil of Punjab to serve as cheap materials for removal of arsenic (As) from water with elevated As concentration. The arsenate adsorptions onto soil and soil + iron fillings are described by a two‐region Langmuir isotherm equation; that is, the plots showed two distinct linear portions. The bonding energy and adsorption maxima for arsenate adsorption by soil increased slightly at higher equilibrium temperature of 305 K relative to 280 K in the Langmuir plot for region I but followed an appreciative decline in both parameters for region II. The addition of iron fillings enhanced the adsorption maxima of arsenic soils by 2.5‐fold because of physical adsorption and 4.44‐fold because of chemisorptions or precipitation at weak and strong As concentrations, respectively, in soil–water equilibrated systems. Thus, the results of the present investigation suggest that water withdrawn from shallow aquifer containing elevated As concentrations should be equilibrated with mixtures of soil and iron fillings for removal of As. After an equilibration period, separation of water by decantation or filtration could be used for drinking purposes for humans and domestic animals.

Monitoring Nutrient Status for Maize in Northwestern India through Diagnostic and Recommendation Integrated System Approach

Diagnostic and recommendation integrated system (DRIS) norms were established for various nutrient ratios obtained from the high-yield population of maize cultivated in submountainous areas of Punjab and were used to compute DRIS indices. Nutrient sufficiency ranges derived from DRIS norms were 1.67–3.12, 0.23–0.43, 0.89–2.56, 0.21–0.50, 0.1–0.32, and 0.10–0.20% for nitrogen (N), phosphorous (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S) and were 181–278, 27–75, 14–29, and 4–8 mg kg−1 for iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu), respectively. According to these DRIS-derived sufficiency ranges, 95, 94, 95, 87, 90, and 86% of samples were sufficient whereas 4, 3, 4, 2, 2, and 2% of samples were low in N, P, K, Ca, Mg, and S, respectively. In micronutrients, 80, 90, 85, and 68% of samples were sufficient, whereas 36 17, 10, 14, and 31% samples had excessive Fe, Mn, Zn, and Cu, respectively. Thus, the DRIS approach can be employed to obtain the fertility status of the soil, and the amount of each nutrient can be computed for balanced utilization of fertilizers.

Monitoring Nutrient Status of Ber (Zizyphus mauritiana) Fruit Trees in Semi-arid and Arid Regions of Northwest India through Diagnostic Recommendation and Integrated System Approach

The Diagnostic Recommendation and Integrated System (DRIS) was employed to interpret nutrient analyses of leaf tissues from ber fruit tree orchards grown in semi-arid and arid areas of Punjab in northwest India. The DRIS norms were established for various nutrient ratios obtained from the high-yield population and were used to compute DRIS indices, which assessed nutrient balance and their orders of limitation to yield. Nutrient sufficiency ranges derived from DRIS norms were 0.688–1.648%, 0.184–0.339%, 1.178–1.855%, 1.064–1.768%, 0.234–0.391%, and 0.124–0.180% for nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S) and were 55–205, 26–80, 17–33, and 5–11 mg kg−1 for iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu), respectively. According to these DRIS-derived sufficiency ranges, 79%, 76%, 76%, 75%, 84%, and 72% of samples were sufficient, whereas 13%, 15%, 21%, 14%, 7%, and 18% of total samples were low in N, P, K, Ca, Mg, and S, respectively. For micronutrients, 84%, 85%, 77%, and 86% of samples were sufficient, whereas 6%, 3%, 8%, and 2% of samples were low in Fe, Mn, Zn, and Cu, respectively.