Greenhouse gas emissions, carbon stocks and wheat productivity following biochar, compost and vermicompost amendments: comparison of non-saline and salt-affected soils.

Understanding the impact of greenhouse gas (GHG) emissions and carbon stock is crucial for effective climate change assessment and agroecosystem management. However, little is known about the effects of organic amendments on GHG emissions and dynamic changes in carbon stocks in salt-affected soils. We conducted a pot experiment with four treatments including control (only fertilizers addition), biochar, vermicompost, and compost on non-saline and salt-affected soils, with the application on a carbon equivalent basis under wheat crop production. Our results revealed that the addition of vermicompost significantly increased soil organic carbon content by 18% in non-saline soil and 52% in salt-affected soil compared to the control leading to improvements in crop productivity i.e., plant dry biomass production by 57% in non-saline soil with vermicompost, while 56% with the same treatment in salt-affected soil. The grain yield was also noted 44 and 50% more with vermicompost treatment in non-saline and salt-affected soil, respectively. Chlorophyll contents were observed maximum with vermicompost in non-saline (24%), and salt-affected soils (22%) with same treatments. Photosynthetic rate (47% and 53%), stomatal conductance (60% and 12%), and relative water contents (38% and 27%) were also noted maximum with the same treatment in non-saline and salt-affected soils, respectively. However, the highest carbon dioxide emissions were observed in vermicompost- and compost-treated soils, leading to an increase in emissions of 46% in non-saline soil and 74% in salt-affected soil compared to the control. The compost treatment resulted in the highest nitrous oxide emissions, with an increase of 57% in non-saline soil and 62% in salt-affected soil compared to the control. In saline and non-saline soils treated with vermicompost, the global warming potential was recorded as 267% and 81% more than the control, respectively. All treatments, except biochar in non-saline soil, showed increased net GHG emissions due to organic amendment application. However, biochar reduced net emissions by 12% in non-saline soil. The application of organic amendments increased soil organic carbon content and crop yield in both non-saline and salt-affected soils. In conclusion, biochar is most effective among all tested organic amendments at increasing soil organic carbon content in both non-saline and salt-affected soils, which could have potential benefits for soil health and crop production.

A critical review on the separation of heavy metal(loid)s from the contaminated water using various agricultural wastes.

Wastewater contamination with heavy metal(loids)s has become a worldwide environmental and public health problem due to their toxic and non-degradable nature. Different methods and technologies have been applied for water/wastewater treatment to mitigate heavy metal(loid)-induced toxicity threat to humans. Among various treatment methods, adsorption is considered the most attractive method because of its high ability and efficiency to remove contaminants from wastewater. Agricultural waste-based adsorbents have gained great attention because of high efficiency to heavy metal(loids)s removal from contaminated water. Chemically modified biosorbents can significantly enhance the stability and adsorption ability of the sorbents. The two mathematical models of sorption, Freundlich and Langmuir isotherm models, have mostly been studied. In kinetic modeling, pseudo-second-order model proved better in most of the studies compared to pseudo-first-order model. The ion exchange and electrostatic attraction are the main mechanisms for adsorption of heavy metal(loid)s on biosorbents. The regeneration has allowed various biosorbents to be recycled and reused up to 4-5 time. Most effective eluents used for regeneration are dilute acids. For practical perspective, biosorbent removal efficiency has been elucidated using various types of wastewater and economic analysis studies. Economic analysis of adsorption process using agricultural waste-based biosorbents proved this approach cheaper compared to traditional commercial adsorbents, such as chemically activated carbon. The review also highlights key research gaps to advance the scope and application of waste peels for the remediation of heavy metal(loid)s-contaminated wastewater.

This review provides new information and insights on the potential utilization of agriculture-based biosorbents for the removal of contaminants, especially heavy metal(loid)s from toxic water/wastewater, as well as their mechanisms, adsorption efficiency, and regeneration ability. For practical perspective, biosorbent adsorption efficiency was elucidated by using various types of wastewater and economic analysis studies.

Organic amendment-mediated reclamation and build-up of soil microbial diversity in salt-affected soils: fostering soil biota for shaping rhizosphere to enhance soil health and crop productivity.

Soil salinization is a serious environmental problem that affects agricultural productivity and sustainability worldwide. Organic amendments have been considered a practical approach for reclaiming salt-affected soils. In addition to improving soil physical and chemical properties, organic amendments have been found to promote the build-up of new halotolerant bacterial species and microbial diversity, which plays a critical role in maintaining soil health, carbon dynamics, crop productivity, and ecosystem functioning. Many reported studies have indicated the development of soil microbial diversity in organic amendments amended soil. But they have reported only the development of microbial diversity and their identification. This review article provides a comprehensive summary of the current knowledge on the use of different organic amendments for the reclamation of salt-affected soils, focusing on their effects on soil properties, microbial processes and species, development of soil microbial diversity, and microbial processes to tolerate salinity levels and their strategies to cope with it. It also discusses the factors affecting the microbial species developments, adaptation and survival, and carbon dynamics. This review is based on the concept of whether addition of specific organic amendment can promote specific halotolerant microbe species, and if it is, then which amendment is responsible for each microbial species' development and factors responsible for their survival in saline environments.

Environmental implications of phosphate-based fertilizer industrial waste and its management practices.

During the green revolution in the mid-twentieth century, the consumption of inorganic phosphorous and phosphate-based fertilizers (P-fertilizers) in the developing world skyrocketed, resulting in a proliferation of P-fertilizer industries. Phosphate-based fertilizer industries are ranked among the most environment-polluting industries. The worldwide phosphorus market, which was 68.5 million metric tons in 2020, is expected to increase at a compound annual growth rate (CAGR) of 2.5% to 81 million metric tons by 2027. The release of untreated hazardous pollutants from these fertilizer industries into the soil, water, and atmosphere has resulted in severe environmental health issues. Excessive surface runoff of phosphorus from agricultural fields and its deposition in water promote the growth of algae and macrophytes and lower dissolved oxygen concentration through eutrophication, which is detrimental to aquatic life. Fluorides (F-) and sulfur dioxide (SO2) and/or heavy metals (potentially toxic elements, PTEs) are also detected in the emissions from these fertilizer industries. The main solid waste generated from the phospho-gypsum plant produced up to 5 tons of di-hydrogen phosphate (H2PO4), including PTEs and radioactive substances. Phosphates and fluorenes from these industries are usually disposed of as sludge in storage ponds or trash piles. Humans inhaling poisonous gases released from the P-fertilizer industries can develop hepatic failure, autoimmune diseases, pulmonary disorders, and other health problems. The objectives of this review are to provide guidelines for eliminating the bottleneck pollutions that occur from the phosphate-based fertilizer industries and explore the management practices for its green development.

TiO2/g-C3N4 Binary Composite as an Efficient Photocatalyst for Biodiesel Production from Jatropha Oil and Dye Degradation.

In the present work, TiO2/g-C3N4 nanocomposites were synthesized by using highly crystalline TiO2 nanorods/rice (NRs) and various percentages of g-C3N4 via a facile, scalable, and inexpensive pyrolysis method. The synthesized nanocomposites were characterized by various techniques, e.g., X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), N2 adsorption and desorption analysis (BET), Fourier transform infrared spectroscopy (FTIR), UV-vis diffuse reflectance spectroscopy (DRS), electrochemical impedance spectroscopy (EIS), and chronoamperometry (CA). It was found that biodiesel production by the esterification reaction can be remarkably enhanced by coupling TiO2 with g-C3N4; hereby, it was observed that with increasing percentage of g-C3N4 from 5 to 10 and 15% with respect to TiO2 NRs, the photocatalytic activity rose and the maximum photocatalytic activity with 97% conversion was observed for NC-3, i.e., 15% g-C3N4/TiO2. Moreover, the photoactivity of pristine TiO2 NR aggregates was contrasted with their nanoparticle morphology and was estimated to be slightly better. When applied for photocatalytic Congo red dye degradation, this sample showed a 91% degradation efficiency using only a very small amount of the catalyst. The high catalytic efficiency is attributed to the narrow band gap, exceptionally high surface area, and efficient charge separation properties of the prepared catalysts.

Unlocking the potential of glyphosate-resistant bacterial strains in biodegradation and maize growth.

Glyphosate [N-(phosphonomethyl)-glycine] is a non-selective herbicide with a broad spectrum activity that is commonly used to control perennial vegetation in agricultural fields. The widespread utilization of glyphosate in agriculture leads to soil, water, and food crop contamination, resulting in human and environmental health consequences. Therefore, it is imperative to devise techniques for enhancing the degradation of glyphosate in soil. Rhizobacteria play a crucial role in degrading organic contaminants. Limited work has been done on exploring the capabilities of indigenously existing glyphosate-degrading rhizobacteria in Pakistani soils. This research attempts to discover whether native bacteria have the glyphosate-degrading ability for a sustainable solution to glyphosate contamination. Therefore, this study explored the potential of 11 native strains isolated from the soil with repeated glyphosate application history and showed resistance against glyphosate at higher concentrations (200 mg kg-1). Five out of eleven strains outperformed in glyphosate degradation and plant growth promotion. High-pressure liquid chromatography showed that, on average, these five strains degraded 98% glyphosate. In addition, these strains promote maize seed germination index and shoot and root fresh biomass up to 73 and 91%, respectively. Furthermore, inoculation gave an average increase of acid phosphatase (57.97%), alkaline phosphatase (1.76-fold), and dehydrogenase activity (1.75-fold) in glyphosate-contaminated soil. The findings indicated the importance of using indigenous rhizobacteria to degrade glyphosate. Therefore, by maintaining soil health, indigenous soil biodiversity can work effectively for the bioremediation of contaminated soils and sustainable crop production in a world facing food security.

Types, sources, socioeconomic impacts, and control strategies of environmental noise: a review.

Noise exposure has reached an alarming degree over the years because of rapid growth in the industry, transportation, and urbanization. Therefore, it is a dire need to provide awareness of the sources and mitigation strategies of noise, and to highlight the health, and socio-economic impacts of noise. A few research studies have documented this emerging issue; however, there is no comprehensive document describing all types of noise, their impacts on living organisms, and control strategies. This review article summarizes the sources of noise; their effects on industrial workers, citizens, and animals; and the value of property in noisy areas. The plethora of literature is showing an increased level of noise in various cities of the world, which have various health consequences such as high blood pressure, insomnia, nausea, heart attack, exhaustion, dizziness, headache, and triggered hearing loss. Apart from humans, noise also affects animal habitat, preying, and reproduction ability; increases heart rate and hearing loss to even death and loss in property value; and impairs the hospital environment. Finally, we have discussed the possible strategies to mitigate the noise problem, policy statements, and regulations to be followed, with future research directions based on the identified research gaps.

Apportionment of heavy metals in a soil-water-plant system via brick kiln emissions in heavily industrialized city of Pakistan.

One of the major environmental problems is the fast accumulation of brick kiln emissions near the peripheries of almost all urban centers. An enormous quantity of substandard coal, wood, rubber tires, or saw wood is used as fuel in these brick kilns, creating environmental pollution through carbon and heavy metals present in the emissions. The present study was designed to determine the distribution pattern of heavy metals in a soil-water-plant system under the influence of brick kiln emissions. Ash, soil (0-15 cm), water, and plant samples were collected from the adjacent areas of the brick kilns. Geo-accumulation index and contamination factors were used to assess the toxicity of metals to soil and plants. It was found that the concentrations of Cd in water, soil, coal, and plant samples were found in the range of 0.004-0.024 mg L-1, 0.02-0.66, 0.002-0.042, and 0.06 to 0.07 mg kg-1, respectively, while Pb concentration was found within the range of 0-0.08 mg L-1, 0.30-8.60, 0.011-0, and 0.01-0.08 mg kg-1 in water, soil, and plant samples, respectively. The concentration of Cd in brick kilns ash was in the range of 0-0.04 mg kg-1 while Pb was found within the range of 0.01-0.05 mg kg-1 for ash. Geo-accumulation index and contamination factor values for Cd were found higher suggesting proper pollution prevention measures to be implemented. Based on the results, it was concluded that Cd concentrations in soil, plants, and water samples were higher in the subject area due to brick kiln emissions and higher Cd concentrations in the fuel material.

Biomagnification of potentially toxic elements in animals consuming fodder irrigated with sewage water.

Globally, sewage water is considered a cheap and effective alternative source of irrigation and nutrient supplement. For example, in Faisalabad, Pakistan untreated sewage water loaded with potentially toxic elements (PTEs) is being routinely used to grow fodder crops in the peri-urban areas, where PTEs accumulate at different trophic levels and contaminate the food chain. Trophic transfer, bioaccumulation, and biomagnification of hazardous metals in food chains had toxic implications for human health. Currently, the major concern is associated with the consumption of PTEs contaminated fodder by animals and the subsequent translocation into humans via consumption of milk and meat from these animals. This study thus analyzed the concentration of Cd, Cu, Pb and Zn in sewage water, sewage irrigated soil, fodder is grown on such soils and the milk of cows and buffalos to calculate the transfer through water and fodder to animal milk. Overall, concentrations and bioaccumulation factors of Cd and Cu in buffalo milk were higher than the cow milk, whereas it was inverse for the concentration of Zn. Non-significant difference in the bioaccumulation factor for Pb in both buffalo and cow milk was observed. Calculation of the estimated daily intake indicated that there was no health risk associated with the consumption of tested milk samples. However, given the widespread exposure of infants to milk, continuous monitoring of milk quality is recommended to preclude a child's exposure to elevated levels of PTEs.

Immobilization of cadmium in soil-plant system through soil and foliar applied silicon.

We conducted a pot experiment to evaluate the potential for soil- and foliar-applied silicon (Si), alone and in combination, to a Cd-contaminated soil in order to evaluate the effects on such amendments on the Cd translocation from soil to wheat root, shoot and grains. Five treatments were used, T1) control with no external factor added, T2 received only Cd, while T3-T5 treatments received Cd in combination with soil, foliar and soil plus foliar applied Si. Except control (T1), soil was contaminated with Cd at 10 mg kg-1 in all the treatments and 1% solution of Si as an amendment was used for soil and/or foliar application or their combination. Overall, while Si application improved both plant growth and yield in Cd-contaminated soil. Control and combined soil- and foliar-applied Si in Cd contaminated treatments showed equally positive (2.5%) increase in plant height over Cd contaminated treatment. Grain yield was also highest in the treatment receiving Cd plus soil-applied Si (29%) followed by control (26%). It was concluded that Si can alleviate Cd toxicity in wheat irrespective of whether the Si was soil-applied or applied via a foliar method, but soil applied Si proved the best in this regard.Novelty statement Immobilization of metals i.e., cadmium (Cd) with soil-applied amendments like biomaterials and organic manure to decrease Cd concentration in plants have already been widely investigated. Silicon (Si) is a cheap in-organic and readily available element in the nature and also used for the same purpose. It can be applied both in soil as well as by foliar and soil + foliar application to decrease the metals concentration in soil and plants. However, comparative effectiveness of these three methods have not been checked simultaneously. In this study, we have studied the comparative effectiveness of Si application to soil, foliar and their combination (soil + foliar) to decrease Cd concentration during wheat crop.

Urban noise assessment and its nonauditory health effects on the residents of Chiniot and Jhang, Punjab, Pakistan.

Elevated noise level is an emerging global problem. Therefore, the present work is conducted that can improve, increase, and integrate the already known issue in literature with new information coming from an emerging country such as Pakistan. The objectives of this study were (i) to assess the urban noise levels and traffic density of Chiniot and Jhang and (ii) to determine nonauditory health effects of noise levels on the residents of both cities. Noise levels were examined from 181 locations (103 from Jhang and 78 from Chiniot) and categorized into hospitals, educational, religious and recreational, residential, industrial areas, and traffic intersections. A-weighted noise level measurements were taken using an integrated sound level meter which recorded short-term road traffic noise continuously for 15 min at each location (LAeq15). The urban noise data showed 82% of the sites in Jhang (LAmax = 103 dB) and 95% in Chiniot (LAmax = 120 dB) exceeded the noise limits set by the National Environment Quality Standard of Pakistan (NEQS-Pak) and World Health Organization (WHO). Moreover, higher intensity of noise levels (LAeq15 ≥ 100 dB) was recorded in Chiniot (17 sites) than in Jhang (1 site). Regression analysis showed a relatively strong relationship of traffic density with noise at Chiniot (R2 = 0.48) compared to Jhang (R2 = 0.31). However, spatial variability of noise with traffic density was observed in both cities. Survey study revealed that all the respondents in Jhang and Chiniot suffered from many noise-related health problems such as annoyance (53 and 51%), depression (45 and 47%), dizziness (61 and 65%), headache (67 and 64%), hypertension (71 and 56%), hearing loss (53 and 56%), physiological stress (65 and 65%), sleeplessness (81 and 84%), and tinnitus (70 and 62%) due to noise, respectively. We conclude that noise levels are higher in Chiniot primarily due to high road traffic and secondarily due to high population density. It is recommended that vehicle maintenance and family and urban planning could be effective measures to reduce urban noise levels.

Surface water quality assessment of Skardu springs using Water Quality Index.

Natural springs which originate from hilly areas of Skardu in Pakistan make their route downward and are utilized by the public as they passes from residential areas. Due to weathering processes in mountainous regions, these springs can be the source of various trace elements and pollutants. Keeping in mind the same concept, ten mostly used freshwater springs were selected to evaluate their drinking water quality in the Skardu region. Three samples of water from each spring (start/mouth, 100 m away from the mouth, and 200 m away from mouth) were collected and analyzed for water quality via Water Quality Index (WQI). The main parameters of spring water were recorded in the laboratory as electrical conductivity (EC), total dissolved solids (TDS), residual sodium carbonate (RSC), and sodium adsorption ratio (SAR), and secondary parameters, i.e., Kelley's ratio (KR), permeability index (PI), and WQI, were derived. Besides these parameters, heavy metal pollutants (Cd, Cr, Mn, and Cu) were also determined from the water samples. The results showed that the assessed parameters TDS, SSP, KR, and PI were found within the safer limits of drinking water as prescribed by the Pak-EPA and WHO. However, among trace elements, only Cd (0.03 mg L-1) was found above the permissible limits of 0.01 mg L-1 as given by the GOP-EPA (2008) and WHO (1996) at Shigri Bala spring 200 m away. Similarly, at 2 ft from the mouth of Chumig S1 spring, its concentrations were recorded 0.03 mg L-1, and at Benazir Chowk spring (100 m away), it was found 0.02 mg L-1. In general, the Water WQI demonstrates that springs have good water quality. Our findings are useful for the environmental protection managers and citizens of the Skardu concerned with the water quality of the springs.

Assessment of noise pollution and its effects on human health in industrial hub of Pakistan.

Faisalabad is one of the major industrial cities of Pakistan, which may cause noise pollution to the local residents due to the development of robust industrial and transport systems. This study aimed at (i) mapping the noise pollution levels at various locations of Faisalabad city; (ii) comparing noise pollution levels in the morning, the afternoon, and the evening for each source; and (iii) assessing nonauditory effects of noise on human health. Two industries and 43 famous/busy locations of Faisalabad Sadar were selected to study noise pollution by using the sound level meter for the period of 24 h. A questionnaire-based survey was carried out near the sampling points to get a public perception about the health impacts of noise pollution. The measured equivalent sound pressure levels (SPLeq) were higher than the permissible limits at all the sampling locations during morning, afternoon, and evening hours. The maximum sound pressure level (SPLmax) was 102 dB inside the production unit in the afternoon at Mian Muhammad Siddiq Textile Loom industry. The average SPL was found at State Bank road (102 dB), Children's Hospital (101 dB), Jhang Bazar (100 dB) in the afternoon and at Punjab Medical College in the evening (97 dB). Based on the survey, 94% of respondents reported headache, 76% sleeplessness, 74% hypertension, 74% physiological stress, 64% elevated blood pressure levels, and 60% dizziness due to noise. Noise pollution is higher than the standard limits and causes auditory as well as nonauditory effects on humans. The vehicles and industrial machinery should be maintained, and sound proofing and protection equipment should be provided to the workforce in order to protect them from extreme noise levels.

The IFN-λ Genetic Polymorphism Association With the Viral Clearance Induced by Hepatitis C Virus Treatment in Pakistani Patients.

BACKGROUND: Polymorphisms in the interferon λ (INF λ) genes on chromosome 19 have been associated with clearance of hepatitis C virus (HCV) induced by interferon and ribavirin therapy however there is no such data available for Pakistani patients with HCV infection. OBJECTIVES: In this study, the effects of single nucleotide polymorphisms (SNPs) have been investigated in response to treatment with interferon-α and ribavirin in a cohort of 75 HCV genotype 3a patients. PATIENTS AND METHODS: A total number of 50 SNPs from the Interferon λ region on chromosome 19 were genotyped to investigate allelic associations with the treatment response in HCV type 3a patients. Thirteen SNPs were associated with HCV clearance, with the most significant alleles being RS8109886 (Fisher's P = 0.0001), RS8113007 (Fisher's P = 0.0001) and RS12979860 (Fisher's P = 0.0002). RESULTS: These SNPs were found to be the most suitable SNPs for predicting treatment response in the present study. These findings support those reported previously. This could be used to improve HCV treatment strategies and suggest that Pakistani patients should be genotyped for the relevant SNPs to identify the patients who are more likely to respond to interferon and ribavirin therapy. CONCLUSIONS: This therapy is costly and can be accompanied by several adverse side-effects, hence pre-treatment prediction of patients who are most likely to benefit would have both economic and patient benefits in the long term.