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The pollution of soils and groundwater by heavy metal pollutants is a widespread environmental problem, particularly in Iran. One cost-effective method to remediate the polluted soils is phytoremediation, in which different plants are used to extract the heavy metals from soil and accumulate them in their organs. In this study, the phytoremediation potential of native plants of Southwestern Iran in removing nickel and lead from polluted soil was assessed separately and in combination with organic amendments of compost and biochar.Hence, the pot experiments were conducted in the greenhouse using soil gathered from the Pazanan oil refineryin Gachsaran, located at Kohgiluyeh and Boyer-Ahmad Province. Then, the hierarchical cluster analysis was applied to classify the different treatments of amendments.The results indicated that the phytoremediation strength of three native species for Ni uptake was C. procera> St. Plumosa > M. sativa; and for Pb uptake was St. Plumosa > C. procera> M. sativa. Also, the utilisation of organic materials originated from urban waste caused to increase in the Ni and Pb accumulation in root and shoot of these species as well as the residual concentration of the metals in soil. Based on the cluster analysis, the treatment of biochar 2% showed the most effect on the residual concentration of heavy metals in soil (1128.00 mgkg−1);the treatment of biochar 1% represented the highest accumulation of metals at the root (158.82 mgkg−1), while all treatments of different amounts of amendments have the same effect on the accumulation of heavy metals in the shoot (151.38 mgkg−1). In general, cluster analysis showed that the organic amendments, especially biochar even at low amounts can improve the phytoremediation capability of the studied native species in removing Ni and Pb from polluted soil. [ABSTRACT FROM AUTHOR]

In order to investigate the possibility of improvement of yield, yield components and the concentration of some nutrients in rice leaves (Tarom variety) by using rice straw and its biochar, a factorial experiment was conducted in the form of a randomized complete block design in nine treatments and three replications in the farm of Sari Agricultural Sciences and Natural Resources University, Sari, north of Iran, in 2021. The first factor was rice straw (S) at three levels of zero, 2 and 4 tons/ha and the second factor was rice straw biochar (B) at three levels of zero, 1 and 2 tons/ha. The maximum concentration of potassium (1.22%), nitrogen (4.73%) and iron (208 mg/kg) in the flag leaf was observed when rice was grown in the high levels of rice straw and particularly its biochar. Also, the concentration of silicon, manganese and zinc in the flag leaf increased with the increase in the levels of rice straw and its biochar. By increasing the use of rice straw and its biochar, the number of tillers, plant height, panicle length, weight of 1000 seeds and the number of filled seeds increased significantly. The combined use of rice straw and its biochar increased the rice grain yield, indicating a 1.78 times increase in the treatment of 2 tons/ha of rice straw biochar + 4 tons/ha of rice straw (S2B2) compared to the control. Therefore, it can be concluded that the application of 2 tons/ha of biochar and 4 tons/ha of rice straw can lead to the maximum grain yield by increasing the concentration of nutrients in the flag leaf and improving the growth and yield components of rice. [ABSTRACT FROM AUTHOR]

Safflower cultivation has been developed in arid regions of Iran in the recent decade. Potassium (K) is an important plant nutrient and its content has been decreased in arid soils due to the intensive agriculture and no K fertilizer application. We tried to monitor K pools distribution and K release in a calcareous soil cultivated with safflower (Carthamus tinctorius L.) under normal irrigation and water stress when treated with wheat biochar (WB), cotton biochar (CB), nitrogen + phosphorus (N + P), N + P + WB and N + P + CB. All fertilizer treatments except N + P increased the contents of soluble, exchangeable, non-exchangeable and HNO3-extractable K by 81-124, 64-98, 14-28 and 31-50%, respectively. The N + P treatment decreased soluble and non-exchangeable K by 10 and 6%, respectively and increased exchangeable K by 12%. Ten times extraction of control soil with 0.01 M CaCl2, 0.01 M oxalic acid and 1% wood vinegar released 270, 250 and 256 mg K kg−1, respectively and cumulative K release increased with all fertilizer treatments except N + P. The CaCl2 solution extracted more K from soil samples, as compared to the oxalic acid and wood vinegar, and this difference was considerable in the first stages of K extraction. Analysis of Al and Ca release proves that exchange reaction is the main mechanism of K extraction with all solutions. Water stress increased soluble K content by 17%. Cumulative K released from soil samples under normal irrigation and water stress were 404 and 417 mg kg−1, respectively. It is concluded that irrigated agriculture in arid regions may decrease soil available K and use of different biochars improves soil K availability and its K release potential. [ABSTRACT FROM AUTHOR]

Three different levels of biochar addition in soil (0, 1, 2 kg m-2) and simultaneous irrigation treatments (50, 85, and 120% of crop Evapotranspiration (ETc)) were applied to basil (Ocimum basilicum L.) for two consecutive years (2018 and 2019). Central Composite Design (CCD) was used as an experimental optimization method, and 13 given experiments were carried out. The study was performed at the research farm of the Ferdowsi University of Mashhad, Iran. The effects of these treatments were evaluated on biochemical attributes (total chlorophyll, total phenol, and total soluble carbohydrates) and morphological criteria (biological yield, height, seed yield, and harvest index). Then, all the results were statistically analyzed. The results revealed that biochar amendment in the soil decreased all examined biochemical characteristics. Meanwhile, biochar in the soil strengthened the morphological properties of the basil plant. Also, the basil plant significantly responded to the amount of irrigation levels. High levels of water treatments reduced total phenol and total soluble carbohydrates and raised all other measured factors. Statistical analysis shows no significant relationship between 2-way-interaction (biocharxirrigation) and measured factors, except total soluble carbohydrates. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of biochar and humic acid on the rate of remobilization, grain yield and antioxidant content of maize under water deficiency stress, an experiment was conducted as asplit-split plot in the form of a randomized complete blocks design with three replications in Ahvaz, southwest of Iran. The main plot involved water stress with three irrigation levels after depleting 30,40 and 50% of field capacity, non-stress, moderate stress, and severe stress, respectively, asubplot withbiochar with 2 control levels (no use of biochar) and application of 4 tons in biochar hectares and another subplot having humic acid with 4 control levels (no use of humic acid) and application of 2, 4 and 6 liters per hectare of humic acid. The results showed that the effect of water deficit stress, biochar and humic acid on grain yield, remobilization rate, current photosynthesis, share of current photosynthesis, catalase and superoxide dismutase enzymes was significant at the level of 1% probability. The highest grain yield was related to irrigation treatment after depleting 40% of field capacity and application of 4 tons per hectare of biochar. In total, the use of 4 liters per hectare of humic acid in moderate moisture stress conditions due to its positive role on the growth and hence on the 42% increase in the yield, compared to severe stress treatment and no consumption of humic acid, can be recommended under arid and semi-arid conditions to save water consumption, and reduce the effects of water deficit stress. [ABSTRACT FROM AUTHOR]

Summary: The root-knot nematode, Meloidogyne javanica , is the most damaging species of plant-parasitic nematodes in eggplant cultivation in Iran. We studied the effect of pistachio and date palm biochars, vermicompost and a mixture of each of these biochars with vermicompost on M. javanica. To investigate the effect of these organic materials on survival, hatching and attraction of the second-stage juvenile (J2) towards the root, bioassays were performed in the laboratory using extracts of organic material. Vermicompost extract increased J2 mortality and decreased hatching and the number of J2 attracted to the eggplant roots. However, either type of biochar alone or mixed with vermicompost did not cause J2 mortality, nor did they inhibit hatching and attraction of J2 towards the root. To determine the effect of organic matter on J2 invasion and reproduction, pot experiments were performed in a completely randomised design with four replications in the glasshouse. Vermicompost reduced the number of J2 that penetrated the roots, number of egg masses and the final population of M. javanica eggs and J2. The suppressing effect of vermicompost might be attributed to the release of toxic compounds such as ammonium and improved soil nutrient and plant growth, leading to plants more tolerant to nematode damage. Pistachio and date biochars alone or combined with vermicompost had no adverse effect on the nematode reproduction compared to non-treated soil. Both types of biochar reduced the suppressing effect of vermicompost, most probably due to the absorbance of suppressive compounds in vermicompost by the high surface area of the biochar. [ABSTRACT FROM AUTHOR]

• A green value chain-based supply chain is designed for pomegranate fruit. • A circular economy based on biochar production is applied for waste management. • Multi-stage stochastic program is designed to address dynamic uncertainty. • Both EVPI and VSS with new metrics are calculated for validation. • An application of the proposed model is investigated with a real case study. Food security is a fundamental prerequisite of human survival. This study focuses on providing a novel bi-objective model for the design of a green closed-loop pomegranate supply chain based on the value chain. To maximize the benefits of circular economy, we propose a thermochemical conversion process and develop a novel hybrid risk-neutral and risk-averse multi-stage stochastic programming (RNRAMSSP) approach to cope with supply uncertainty. We employ the expected value of perfect information (EVPI) and value of stochastic solution (VSS) to validate the proposed approach. For the VSS metric, we define a novel measure to compare the worst-case cost of the stochastic and deterministic model solutions. To demonstrate the applicability of the proposed model, we provide a real case study in Iran. Based on the VSS metric, the risk-neutral and risk-averse stochastic model solutions save up to 1% and 1.76% in the worst-case cost, respectively, compared to the deterministic model. [Display omitted] [ABSTRACT FROM AUTHOR]

Rangelands are very diverse, and they spread from low vegetation desert areas to those with more rainfall and more cover. In saline and desert areas, there are many restrictions on vegetation establishment, hence the use of amendments. The study area is located south of Nazarabad city in Alborz province, Iran. In this study, different amendments, such as mineral biochar, arbuscular mycorrhiza fungi (AMF), and acrylic resin polymer (ARP) were utilized at the base of Nitraria schoberi seedlings. Each amendment was used at four levels. A total of 13 treatments (each treatment with 10 replicates) were evaluated. Five soil samples were taken from each treatment to determine the physical and chemical properties of soil (pH, EC, C, N, P, K, C/N, bulk density, particle density, pores, moisture, soil texture) for testing. The results showed that on average, more than 60% of the soil texture was clay. Furthermore, the used amendments had different effects on the physical and chemical properties of the soil. Biochar increased the carbon and nitrogen content of the soil at all levels. Moreover, AMF increased soil nitrogen and carbon, and ARP reduced soil bulk density and increased soil porosity, moisture, nitrogen, and carbon content. With increasing the level of biochar and ARP, negative effects were observed, and these amendments increased soil acidity and salinity in the study area; however, AMF reduced the soil salinity in the study area. [ABSTRACT FROM AUTHOR]

Fruits and citrus wastes are generated in the food industry in large quantities. Their management in Iran, as one of the major hubs of fruits and citrus production, is of great importance. In this study, the biochar samples were prepared from pomegranate, orange and lemon peel waste produced in a juice factory using the pyrolysis process in the range of 400- 500 °C; then their efficiency for zinc adsorption from an aqueous solution was investigated. The kinetic and isotherm data of zinc adsorption were fitted by the linear and nonlinear forms of the Langmuir and Frendlich isotherm models and the first-order and second-order pseudo-kinetics models. The results showed that under the experimental conditions applied, the maximum amount of zinc absorption by biochars derived from pomegranate, orange and lemon peel was 2.42, 1.83 and 3.17 mg/g, respectively. The results of adsorption isotherm models also showed that the use of the linear form could lead to a completely different interpretation, as compared to the original form of the model. Based on the linear forms, the Langmuir isotherm was the best; meanwhile, according to the non-linear forms, the Freundlich isotherm was the best model to describe the adsorption data. In addition, the reaction kinetics indicated that both original and linear models had the same results, and the data were better fitted by the pseudo-second order model. [ABSTRACT FROM AUTHOR]

Due to the heavy costs of wind erosion control measures, the correct selection of technical methods is indispensable for a sustainable land management in arid and semiarid regions. Thus, the main goal of this research was to investigate the feasibility of using the clay minerals (i.e., bentonite), polyvinyl acetate and palm biochar for reducing the wind erosion in deserts surrounding the cities. The treatments were sprayed uniformly onto the containers (5 × 35 × 105 cm, 0.37 m2) with sand (collected from sand dunes surrounding Isfahan city, central Iran) in 3 replicates. The experiments were conducted in a wind tunnel with sequential repetitions after 1, 10, and 20 weeks. Among the studied treatments, the bentonite planters demonstrated to be the most effective soil erosion control measure by reducing soil loss and improving sand ablation. On the contrary, the palm biochar had less influence on the soil erosion control and only a slight effect on the threshold speed. For the future, further studies are required to select the best and most relevant soil erosion control measures under field conditions considering all the environmental aspects in arid regions of Iran. [ABSTRACT FROM AUTHOR]

Biochar addition to soil has been found to be a useful practice to control erosion. However, few studies have explored the effects of biochar produced from husk of rice on rill erosion, due to overland flow in deforested areas. This study has evaluated the rill detachment capacity (D c) and erodibility (K r) in soil samples treated with rice husk biochar in comparison to untreated sites (control), collected in deforested hillslopes of Northern Iran. D c was measured in a lab-scale hydraulic flume at four-bed slopes (9.7, 14.3, 19.5, and 24.2%) and five water discharges (0.24, 0.36, 0.47, 0.59, and 0.69 L m−1 s−1). Moreover, organic carbon, aggregate stability and bulk density of soils were measured. D c was lower (on average − 32%) in the treated soil compared to the control. D c was not correlated to the other physico-chemical properties of soil. K r , estimated by linear regressions between D c and shear stress, was noticeably lower (−79%) in the treated soil compared to the control. These results evidence that rice husk biochar is effective at controlling and mitigating soil detachment, and at improving organic matter content and aggregate stability in deforested hillslopes. The proposed values of rill erodibility and shear stress of deforested hillslopes (treated or untreated) are helpful to model soil resistance to rill erosion in process-based erosion models. • Scarce knowledge exists about biochar effects on rill detachment capacity (D c). • D c was lower by 32% in the soil treated with biochar compared to the untreated soil. • This reduction was due to organic matter addition to soil treated with biochar. • D c was not correlated to the other physico-chemical properties of soil. • Rill erodibility was lower (−79%) in the soil treated with biochar. [ABSTRACT FROM AUTHOR]

The use of biochar can improve the various soil properties and reduce erosion. Also, biochar production has caused the optimal use of agricultural and industrial waste and can convert waste into useful compounds. A large mass of leaves and pruned barberry and jujube branches are abandoned annually without planning to use in South Khorasan. Therefore, in this experiment, the impact of biochars produced from barberry and jujube pruned materials (after six months) on the rate of soil erosion, nutrient, and soil properties were studied in the laboratory conditions at the University of Birjand, Iran, in 2021. Biochar treatments were examined at three 0%, 2%, and 5% levels by weight with four replications. Physicochemical and biological properties and soil nutrients were measured before and after adding biochars and applying erosion. The amount of soil loss was calculated by a standard portable rainfall simulator (a rainfall with an intensity of 160 mm/h for 15 min). The data was investigated using variance analysis and mean comparison (by LSD test and P ≤ 0.05), based on a completely randomized design by JMP13 software. The H/C ratio in the barberry and jujube biochars was about 0.33 and 0.53, respectively. Using the biochars at the 2% and 5% application levels significantly decreased soil erosion and improved soil properties. The 5% barberry biochar treatment caused the greatest reduction in bulk density and soil loss. Moreover, this treatment greatly increased the mean weight diameter of aggregates, saturation moisture, cation exchange capacity, organic matter, microbial biomass carbon, microbial respiration, and substrate-induced respiration of the soil compared to the other treatments. It was also more efficient in increasing and retaining soil nutrients. Using the produced biochars is recommended to improve the soil properties. [Display omitted] • Carbon in the barberry and jujube biochars is very stable and stable, respectively. • Using the study biochars significantly improves the important soil properties. • The biochars have a significant effect on the soil nutrients. • The biochars have an important role in decreasing soil erosion. • Use of the barberry biochar 5% level is more efficient to improve soil properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biochar and AM fungi under reduced irrigation regimes were studied on sunflower. • Sunflower physiological performance, seed yield and oil content were evaluated. • Biochar combined with AM fungi improve growth and physiological plant performance. • Antioxidant enzymes were enhanced in drought stressed plants by biochar and AM fungi. • Biochar and AM fungi application may support sunflower yield under drought climate. Arbuscular mycorrhizal (AM) fungi and biochar have been successfully adopted to improve crop growth and yield under water stressed environments, however, to date little evidence of their combined effects has been reported. Field trials were conducted in 2018 and 2019 growing seasons in northern Iran to evaluate how biochar and AM fungi could improve sunflower (Helianthus annuus L.) productivity subjected to reduced irrigation regimes. A randomized complete block design was adopted with the following treatments: three irrigation regimes [no deficit irrigation (NDI), moderate deficit irrigation (MDI) and severe deficit irrigation (SDI) that was calculated as the 50, 30, and 10 % of maximum available water, respectively]; three biochar rates [0 (B 0), 2.5 (B 2.5) and 5 (B 5) t ha−1 of biochar]; and two AM fungi inoculations [inoculated (AM+) and no-inoculated (AM-) plants]. All treatments were replicated three times. Before plowing, biochar (B 2.5 and B 5) was uniformly distributed on the soil surface to incorporate in the soil profile, while AM fungi (AM+) were distributed in the furrow of sunflower rows before sowing. Biochar and AM fungi were not applied in B 0 and AM- treatments, respectively. Sunflower growth rate, pigments, photosynthesis rate and associated aspects, minerals content, antioxidant enzymes, abscisic acid, total phenolics and seed yield were measured. The results showed that growth parameters, radiation use efficiency, leaf pigments and seed yield decreased under irrigation regimes (NDI > MDI > SDI), while malondialdehyde (MDA) and hydrogen peroxide (H 2 O 2) showed opposite trends. The combination AM fungi and biochar enhanced antioxidant enzymes activities, osmoprotectants, nutrient content and relative water content resulting in a significant decrease in oxidative damage in the drought stressed plants. Seed yield ranged from 4.95 to 1.78 t ha−1 and it was increased by the biochar application (+9% and +7% in B 2.5 and B 5 , respectively) and AM fungi inoculation (+21 % in AM+) in all irrigation regimes. Overall, the plant's performance observed in the MDI-B 5 -AM+ was similar to that in NDI-B 0 -AM- indicating that AM fungi and biochar allow a reduction of water irrigation while maintaining crop yield. According to results, the combination of AM fungi and biochar rate should be adopted as a water-saving practice for sustainable production of sunflower cultivated in semi-arid environments, even if further studies should be carried out to evaluate their effects on other crops and environments. [ABSTRACT FROM AUTHOR]

Although pesticides are widely used in agriculture, industry and households, they pose a risk to human health and ecosystems. Based on target organisms, the main types of pesticides are herbicides, insecticides and fungicides, of which herbicides accounted for 46% of the total pesticide usage worldwide. The movement of pesticides into water bodies occurs through run-off, spray drift, leaching, and sub-surface drainage, all of which have negative impacts on aquatic environments and humans. We sought to define the critical factors affecting the fluxes of contaminants into receiving waters. We also aimed to specify the feasibility of using sorbents to remove pesticides from waterways. In Karun River in Iran (1.21 × 105 ng/L), pesticide concentrations are above regulatory limits. The concentration of pesticides in fish can reach 26.1 × 103 μg/kg, specifically methoxychlor herbicide in Perca fluviatilis in Lithuania. During the last years, research has focused on elimination of organic pollutants, such as pesticides, from aqueous solution. Pesticide adsorption onto low-cost materials can effectively remediate contaminated waters. In particular, nanoparticle adsorbents and carbon-based adsorbents exhibit high performance (nearly 100%) in removing pesticides from water bodies. Image 1 • Pesticides concentrations in water varied widely from 6.8 to 121222 ng/L. • A high concentration of Endosulfan was detected in Rohu Fish in India. • Carbon-based adsorbents and nano-adsorbents could remove up to 100% pesticides. • Mostly organic desorbents have been used for regeneration of adsorbents. [ABSTRACT FROM AUTHOR]