• Energy Research

Pollution is a significant problem in both industrialized and developing countries, as well as in some developed countries. Heavy metal pollution poses a crucial concern for communities due to its detrimental impact on human health and the long-term well-being of the planet. Heavy metals, such as cadmium, chromium, arsenic, lead, and mercury, do not degrade and can enter the food chain, leading to significant health risks. Therefore, it is essential to monitor and take necessary steps to eliminate heavy metal residues that may be present in food, beverages, and the environment. Although the exact role of nanomaterials in pollution cleanup is still unclear, nanotechnology holds promise as a future solution. In the first part of this comprehensive review, a brief overview of nanoremediation is provided. The subsequent sections delve into various nanomaterials and their potential applications in different pollution cleanup scenarios. Following that, critical analysis is conducted on different nano-remediation methods, including oxidation, adsorption, chemical precipitation, filtration, ion exchange, coagulation-flocculation, and photo-catalysis. Lastly, further suggestions are put forward regarding the future utilization of nanotechnology for more effective and enduring pollution cleanup, particularly in eliminating heavy metals.

AbstractThe pollution of soil and aquatic systems by inorganic and organic chemicals has become a global concern. Economical, eco-friendly, and sustainable solutions are direly required to alleviate the deleterious effects of these chemicals to ensure human well-being and environmental sustainability. In recent decades, biochar has emerged as an efficient material encompassing huge potential to decontaminate a wide range of pollutants from soil and aquatic systems. However, the application of raw biochars for pollutant remediation is confronting a major challenge of not getting the desired decontamination results due to its specific properties. Thus, multiple functionalizing/modification techniques have been introduced to alter the physicochemical and molecular attributes of biochars to increase their efficacy in environmental remediation. This review provides a comprehensive overview of the latest advancements in developing multiple functionalized/modified biochars via biological and other physiochemical techniques. Related mechanisms and further applications of multiple modified biochar in soil and water systems remediation have been discussed and summarized. Furthermore, existing research gaps and challenges are discussed, as well as further study needs are suggested. This work epitomizes the scientific prospects for a complete understanding of employing modified biochar as an efficient candidate for the decontamination of polluted soil and water systems for regenerative development.

AbstractDrought poses a significant ecological threat that limits the production of crops worldwide. The objective of this study to examine the impact of soil applied biochar (BC) and peatmoss (PM) on the morpho-biochemical and quality traits of tobacco plants under drought conditions. In the present experiment work, a pot trial was conducted with two levels of drought severity (~ well-watered 75 ± 5% field capacity) and severe drought stress (~ 35 ± 5% field capacity), two levels of peatmoss (PM) @ 5% [PM+ (with peatmoss) and PM- (without peatmoss)] and three levels of rice straw biochar (BC0 = no biochar; BC1 = 150 mg kg− 1; and BC2 = 300 mg kg− 1 of soil) in tobacco plants. The results indicate that drought conditions significantly impacted the performance of tobacco plants. However, the combined approach of BC and PM significantly improved the growth, biomass, and total chlorophyll content (27.94%) and carotenoids (32.00%) of tobacco. This study further revealed that the drought conditions decreased the production of lipid peroxidation and proline accumulation. But the synergistic approach of BC and PM application increased soluble sugars (17.63 and 12.20%), soluble protein (31.16 and 15.88%), decreased the proline accumulation (13.92 and 9.03%), and MDA content (16.40 and 8.62%) under control and drought stressed conditions, respectively. Furthermore, the combined approach of BC and PM also improved the leaf potassium content (19.02%) by limiting the chloride ions (33.33%) under drought stressed conditions. Altogether, the balanced application of PM and BC has significant potential as an effective approach and sustainable method to increase the tolerance of tobacco plants subjected to drought conditions. This research uniquely highlights the combined potential of PM and BC as an eco-friendly strategy to enhance plant resilience under drought conditions, offering new insights into sustainable agricultural practices.

AbstractLarge amount of wastes are burnt or left to decompose on site or at landfills where they cause air pollution and nutrient leaching to groundwater. Waste management strategies that return these food wastes to agricultural soils recover the carbon and nutrients that would otherwise have been lost, enrich soils and improve crop productivity. The incorporation of liming materials can neutralize the protons released, hence reducing soil acidity and its adverse impacts to the soil environment, food security, and human health. Biochar derived from organic residues is becoming a source of carbon input to soil and provides multifunctional values. Biochar can be alkaline in nature, with the level of alkalinity dependent upon the feedstock and processing conditions. This study conducted a characterization of biochar derived from the pyrolysis process of eggplant and Acacia nilotica bark at temperatures of 300 °C and 600 °C. An analysis was conducted on the biochar kinds to determine their pH, phosphorus (P), as well as other elemental composition. The proximate analysis was conducted by the ASTM standard 1762-84, while the surface morphological features were measured using a scanning electron microscope. The biochar derived from Acacia nilotica bark exhibited a greater yield and higher level of fixed carbon while possessing a lower content of ash and volatile components compared to biochar derived from eggplant. The eggplant biochar exhibits a higher liming ability at 600 °C compared to the acacia nilotica bark-derived biochar. The calcium carbonate equivalent, pH, potassium (K), and phosphorus (P) levels in eggplant biochars increased as the pyrolysis temperature increased. The results suggest that biochar derived from eggplant could be a beneficial resource for storing carbon in the soil, as well as for addressing soil acidity and enhancing nutrients availability, particularly potassium and phosphorus in acidic soils.

The Ciprofloxacin (CIP) toxicity and salinity stress in agricultural soils cause risk to environmental and food safety. Consequently, it is essential to devise or use more effective techniques for mitigating salinity and ciprofloxacin-induced stress in soil. This study includes the nZVI-loaded biochar synthesis, integrating the unique characteristics of raw biochar with nZVI. The present study examined the impact of raw and nZVI-loaded biochar on soil quality and the mitigation of salinity stress and Ciprofloxacin toxicity in wheat plants. The results showed that the application of nZVI-loaded biochar treatments led to substantial enhancement in shoot biomass, root biomass, grain biomass, and spike biomass by 152.1, 54.3 %, 59.8 %, and 151 %, respectively compared to control treatment. The treatment with nZVI-loaded biochar significantly increased the rates of photosynthesis and transpiration, as well as the conductance of stomata. It also resulted in higher levels of intercellular CO2, photosynthetic pigments, and water use efficiency with increases of 49 %, 59 %, 57 %, 37 %, 40 %, and 95 %, respectively. The nZVI-loaded biochar significantly decreased electrolyte leakage, malondialdehyde (MDA), and hydrogen peroxide levels compared to the NaCl treatment alone. It also enhanced the activities of enzymatic antioxidants such as peroxidase (POD), superoxide dismutase (SOD), catalase (CAT), guaiacol peroxidase (GPX), and ascorbate peroxidase (APX). The non-enzymatic antioxidants including total soluble sugars (TSS), flavonoids, total soluble proteins (TSP), phenolics, ascorbic acid, anthocyanin, proline, and glycine betaine significantly influenced by the nZVI-loaded biochar. The nZVI-loaded biochar effectively alleviates the stress of soils that are contaminated with hazardous amounts of Ciprofloxacin while improving the soil and plant health.

AbstractFertilizers application are widely used to get a higher yield in agricultural fields. Nutrient management can be improved by cultivating leguminous species in order to obtain a better understanding of the mechanisms that increase the amount of available phosphorus (P) and potassium (K) through fertilizer treatments. A pot experiment was conducted to identify the leguminous species (i.e., chickpea and pea) under various fertilizer treatments. Experimental design is as follows: T0 (control: no fertilizer was applied), T1: P applied at the level of (90 kg ha−1), T2: (K applied at the level of 90 kg ha−1), and T3: (PK applied both at 90 kg ha−1). All fertilizer treatments significantly (p < 0.05) improved the nutrient accumulation abilities and enzymes activities. The T3 treatment showed highest N uptake in chickpea was 37.0%, compared to T0. While T3 developed greater N uptake in pea by 151.4% than the control. However, T3 treatment also increased microbial biomass phosphorus in both species i.e., 95.7% and 81.5% in chickpeas and peas, respectively, compared to T0 treatment. In chickpeas, T1 treatment stimulated NAGase activities by 52.4%, and T2 developed URase activities by 50.1% higher than control. In contrast, T3 treatment enhanced both BGase and Phase enzyme activities, i.e., 55.8% and 33.9%, respectively, compared to the T0 treatment. Only the T3 treatment improved the activities of enzymes in the pea species (i.e., BGase was 149.7%, URase was 111.9%, Phase was 81.1%, and NAGase was 70.0%) compared to the control. Therefore, adding combined P and K fertilizer applications to the soil can increase the activity of enzymes in both legume species, and changes in microbial biomass P and soil nutrient availability make it easier for plants to uptake the nutrients.

Nitrogen (N) losses are prevalent under South East Asia’s due to high N fertilizer inputs, but low N fertilizer use efficiency. This leaves a large quantity of reactive N at risk of loss to the environment. Biochar has been found to reduce N losses across a variety of soil types, however, there is limited data available for semi-arid climates, particularly at a field-scale. Herein we present an exploration of the biological and chemical enhancement effects observed of a cotton stalk-based biochar on wheat growth and yield under arid field conditions. The biochar was treated with urea-N and biofertilizer (bio-power) in different treatment setups. The six experimental treatments included; (i) a full N dose “recommended for wheat crops in the region” (104 kg N ha−1) as a positive control; (ii) a half N dose (52 kg N ha−1); (iii) a half N dose + biofertilizer (4.94 kg ha−1) as a soil mixture; (iv) a half N dose + biofertilizer as a seed inoculation; (v) a full N dose as broadcast + biochar (5 t ha−1) inoculated with biofertilizer; and (vi) a full N dose loaded on biochar + biofertilizer applied as a soil mixture. The half dose N application or biofertilizer addition as soil mix/seed inoculated/biochar inoculation with biofertilizer caused reduced wheat growth and yield compared to the control (conventional N fertilization). However, co-application of chemically enhanced biochar (loaded with a full N dose) and biofertilizer as soil mixture significantly increased the crop growth rate (CGR) and leaf area index (LAI). A significantly higher crop growth and canopy development led to a higher light interception and radiation use efficiency (RUE) for total dry matter (TDM) and grain yield (11% greater than control) production compared to the control. A greater grain yield, observed for the full N dose loaded on biochar + biofertilizer applied as a soil mixture, is attributed to prolonged N availability as indicated by greater plant and soil N content at harvest and different crop growth stages, respectively. The present study has improved our understanding of how the application of nitrogen loaded biochar and biofertilizer as soil mixtures can synergize to positively affect wheat growth and soil-nitrogen retention under arid environmental conditions.

Current industrial developments, advanced farming techniques, and further anthropogenic activities are adding substantial amounts of heavy metals into the ecosystem and having dangerous effects on lifeforms, including plants and animals, and changing their biological activities. Decontamination following the heavy metal contamination is an important point deserving attention in the current scenario. Among all the other approaches used for this purpose, bioremediation is ecofriendly and green approach that can be used to remediate heavy metal toxicity. In plant cells, the regulation of ionic homeostasis is a primary physiological prerequisite for upholding plant development, growth, and production. To avoid the dreadful effects of toxic heavy metal exposure, plants manifest physiological, biochemical, and structural responses. In the present research, we reported on the isolation and molecular identification of an effective heavy-metal-tolerant bacterial strain, Staphylococcus lentus (E3), having a minimum inhibitory concentration of 300 µg/mL for chromium, Cr, taken from soil polluted with industrial effluents at Kasur, Pakistan. Bacterial inoculations enhanced all the growth parameters of Triticum aestivum and Helianthus annus. To observe the physiological strain, the proline content and peroxidase (POD) activities were estimated under Cr stress in the bacterial-inoculated plants. The chlorophyll content and Cr uptake in the aerial parts the of plants were also studied, along with the overexpression of proteins. The bacterial inoculations produced encouraging results. Bioremediation using PGPR is an efficient, convincing, and reliable approach to attenuating heavy metal toxicity.