This study highlights the impact of formal agricultural practices and their adverse effect on the deterioration of underground water quality, with special emphasis on toxic elements, including pesticides, herbicides, fungicides, plasticizer accumulation and heavy-metal contamination. A comprehensive study was conducted at various recently developed societies of Sadiqabad that were formerly used for agricultural purposes. Ten various societies were selected, and three samples from each society were collected from different regions of these areas. Data regarding the physicochemical properties, metal contamination and accumulation of pesticide residues were determined using standard protocols. The results revealed that almost all the physicochemical properties of water samples selected from these sites were close to the WHO’s recommended limits. The range for physicochemical properties was pH (6.4–7.7), electrical conductivity (168–766 µ S cm⁻¹), turbidity (6–17 NTU), total hardness (218–1030 mg L⁻¹), chloride contents (130–870 mg L⁻¹) and phosphate contents (2.55–5.11 mg L⁻¹). Among heavy metals, lead and arsenic concentrations in all sampling sites were found to be above the recommended limits. The decreasing pattern in terms of water-quality deterioration with respect to physicochemical properties was FFT > USM > CRH > UCS > CHS > MAH > FFC > CGA > GIH > AGS. Overall, 95 different kinds of toxic elements, including pesticides, herbicides, plasticizer, etc., were detected in the groundwater samples. The toxic compounds in the groundwater were categorized into pesticides, herbicides, plasticizer, plant growth regulators, fungicides, acaricides and insecticides. Most of these parameters showed peak values at the Fatima Fertilizer Company area and Chief Residencia Housing Society. Pesticide contamination showed that water-filtration plants have a big positive impact on the drinking quality of water. Proper monitoring of the pesticides must be performed, as the majority of the pesticides showed low priority. The monitoring method of the pesticides needs to be updated so that the occurrence of recently authorized pesticides is demonstrated.

The present study aimed to assess the relationship of soil properties in salt-affected soils. The soil samples were collected from 14 districts of Pakistan. Soil salinity and sodicity are the common features of the arid and semiarid regions. The effects of the salt’s interactions with soil micronutrients have not been well studied. Therefore, saline and non-saline soil samples were collected from different locations. The microelements (Fe, Cu, Mn, and Zn) were fractionated into water-soluble, exchangeable, carbonate, Fe + Mn oxide, organic, and residual fractions. Univariate and multivariate analysis (PCA) was carried out to determine the linear relationship between soil properties and micronutrients fractions. Results showed that the magnitude of micronutrients appeared to be affected by the salinity in soils. In saline soil, the Fe fractions differed in the order of residual > organic bound > Fe + Mn bound > carbonate bound > exchangeable > water soluble. Iron fractions varied in the non-saline soils as residual > Fe + Mn bound > organic bound > exchangeable > carbonate bound > water soluble. Copper concentration was higher in the residual and carbonate forms, and the amount was lower in the exchangeable and water-soluble forms under both saline and non-saline conditions. The water-soluble Mn fraction was lower, and the residual Mn fraction was proportionately higher than other forms of Mn in soils. Zinc was found mostly in the residual fraction in both saline and non-saline soils. The mobility factor of micronutrients in non-saline soil was greater than in saline soil. PCA revealed that organic matter (OM) and pH directly affected the fractionation of Cu, Mn, Zn, and Fe in soil. Thus, it could be inferred that salts can bring changes to the composition of micronutrients depending on the nature of the soil and the magnitude of salts.

Phosphorus (P) fractionation is the validation of the nature, solubility and relative bioavailability of P. A sequential P extraction was used to determine the distribution of plant-available P fractions in soils. The relationships of these P fractions to soil properties and foliar P contents were also determined. Results of this study showed substantial differences in soil properties among orchards. Higher amounts of soil organic matter (SOM), cation exchange capacity (CEC) and major plant nutrients were found under orchard soils when compared with control soil. Most of the soil variables varied among orchard species as loquat > citrus > guava. The orchard soil exhibited a slightly higher soil pH. Overall, the P fractions were higher in all types of orchard soils and lowered in the control soils. Among tree species, P fractions in soils were achieved as loquat > citrus > guava. The extracting agents differed for P in the order residual P > HCl-P > NaOH-P > NaHCO₃-P > H₂O-P. Mostly higher amounts of the P fractions were achieved in the topsoil. The average amount of extractable P was found significantly higher in those soils of fruit orchards where the total amount of P was actually higher. The higher r² values between P fractions versus SOM, clay and CEC of soils predicted a strong interrelationship among these soil variables. Leaf N contents of loquat and guava trees were consistently higher, and leaf P contents varied as loquat > citrus > guava. Potassium and Ca contents were higher in citrus than in the other two species. Micronutrients were found as Fe > Zn > Mn > Cu in the leaves. Regression models indicated a sufficient relationship between Hedley P fractions and the foliar P contents in tree species. This study indicates that the above soil properties can be used to ascertain soil P fractions, and that can influence the bioavailability of P from orchard soils.

This study investigated the ability of a HYDRUS 1D model for predicting the vertical distribution of potassium iodine (200 ppm) in soil columns after amendment with five different common remediation materials (gypsum, lime, fly ash, charcoal, and sawdust) at a rate of 2.5% (w/w), relative to an unamended control soil. Results showed that relative to the unamended soil, iodine leaching was decreased by all amendments but that the magnitude of the decreases varied with the soil amendment applied. Iodine content was highest in the upper layer of the soil columns and decreased progressively with soil depth. The model was evaluated via comparison of the model simulated values with measured values from the soil column studies. The results showed that the HYDRUS 1D model efficiency was near to 1, indicating the stimulated results near to the measured values. Therefore, this study showed that iodine leaching through a soil could be ascertained well using a HYDRUS 1D model. The model over predicted iodine leaching, results in a weak correspondence between the simulated and the measured results for iodine leaching. This suggests that the HYDRUS-1D model does not explain accurately different organic and inorganic amended soil and the preferential flow that occurs in these columns. This may be due to the fact that Freundlich isotherm, which is part of the transport equations, does not sufficiently describe the mechanism of iodine adsorption onto the soil particles. This study would help to select an amendment for an effective management strategy to reduce exogenous iodine losses from agro-ecosystems. This would also improve scientific understanding of iodine transport in soil profile.

Globally, the rapid growth of the population over the past century has put enormous pressure on freshwater resources. Pakistan, as a developing country, also faces a freshwater crisis. Rawal Lake, an essential freshwater reservoir near Pakistan’s capital, has been showing signs of deterioration for the past few years. Therefore, a brief study was planned to analyze the water quality of the lake and the associated recharge streams. Twelve physical and chemical parameters were selected along with the total bacterial and Escherichia coli count. Five sampling points were selected for water sampling. Results showed that the Mallpur stream significantly has higher pH, total suspended solids, and total dissolved solids values than the other sampling points and was not within the permissible limits of the World Health Organization. In the case of total bacterial count and Escherichia coli count, except Spillway, water samples showed higher concentrations than the permissible limits of world health organization. However, the mineral content such as Calcium, Magnesium, Nitrogen, Potassium, Chloride, and sulphate concentration at all sampling points are within the permissible limits of the world health organization’s drinking water standard. Results also showed that the water sampled from the Korang River tributary has more deterioration in physicochemical properties as well as in total bacterial count than the Mallpur tributary. Due to the deterioration of the water quality parameter, it is suggested that Rawal Lake water is not suitable for human consumption.