High Organic Matter Content Research Articles

Biochar Regulates the Humification of Kitchen Waste and the Effects of the Humic Acid Structure of Products on Black Soil

Kitchen waste is a misplaced resource that is characterized by a high organic matter content, high water content, and a tendency to rot easily. Biochar is a black solid substance produced under high-temperature, anaerobic conditions using agricultural organic wastes as the raw material. It possesses a large specific surface area, a loose and porous structure, and functional groups, which confer high thermal stability and strong adsorption capabilities. However, little is known about how humic products made from biochar affect the composition and structure of soil humus. To solve the above problems, this study carried out a two-year outdoor field experiment by means of element analysis, infrared spectroscopy, and differential thermal analysis (0.4 kg/m2 (W4), 0.8 kg/m2 (W8), 1.2 kg/m2 (W12), 1.6 kg/m2 (W16), and 2.0 kg/m2 (W20)); CK was the blank control (no application). The samples were collected one year and two years after they returned to the field. The results showed that the application of organic materials facilitated the accumulation of soil organic carbon (SOC) and increased the total nitrogen (TN) content. The highest SOC content in the W20 treatment was 12.39 g/kg and 14.67 g/kg in one and two years, respectively. The maximum relative HA content in the W20 treatment was 22.99% one year after returning to the field. The PQ value (the ratio of HA/(fulvic acid (FA) + HA)) for the W20 treatment was 88.21%. The W20 treatment greatly increased the SOC and humus carbon contents. Compared with the CK treatment, all the organic materials applied for one year improved the structure of the humic acid to varying degrees, increased the degree of oxidation, reduced the degree of condensation and thermal stability of the HA in the soil, and gradually simplified the structure of the humic acid; among all the treatments, the W20 treatment had the greatest effect.

The Relationship Standardized Precipitation Evapotranspiration Index (SPEI) and Forage Value of Rubus Species Collected from Türkiye’s Flora

The increasing drought caused by climate change makes it difficult for rural areas reliant on pasture-based livestock farming to sustain their agricultural practices. Blackberries, a spreading species, have been selected as the material for this study due to their perennial shrub nature and their tolerance to adverse environmental conditions. Türkiye, the gene center for blackberries, is part of the Mediterranean belt and is located at the intersection of three flora regions—Mediterranean, Euro-Siberian, and Irano-Turanian. This study aims to determine the forage value of the Rubus species and other shrub/tree species (Quercus, Pistacia, and Rosa) collected and identified from these flora regions. Furthermore, a linear regression analysis established a relationship between the forage values and the SPEI, a drought index, considering the combined effects of rainfall and temperature in the collection regions. Among the Rubus species, the highest organic matter content (887.8 g kg−1) was obtained from R. pruinosus. In comparison, the highest protein content (240.1 g kg−1) was found in cultivated blackberries in the Euro-Siberian flora region. P. lentiscus had the highest Ca content (14.4 g kg−1) and offered feed at the “Prime” level with 154 of RFV. The SPEI explained 87% of the variation in fructan, 89% in Mg, and 92% in ADF. Due to the perennial nature of the species studied, a strong relationship was found between their growth and forage values over a 48-month time scale using the SPEI. Consequently, the equations related to ADF, Mg, and fructan content obtained in this study can be recommended for woody species.

Occurrence and distribution of atrazine in groundwater from agricultural areas in China

There has been heavy application of chemical pesticides to farmland worldwide. As a state with a heavy emphasis on farming, China has extensively applied chemical pesticides to farmlands. Atrazine (ATZ), one of the most widely used herbicide in the world, has been used in large quantities in weed control in many crops, which poses a relatively large threat to groundwater utilization and agricultural safety. A nationwide sampling and analysis of ATZ in 8146 groundwater monitoring wells from 10 main grain producing areas were conducted during 2019. The results showed that the detection rate of ATZ in groundwater was 40.79 %, with detected concentrations up to 2.86 μg/L. ATZ detection rate was significantly higher in phreatic aquifers than confined aquifer. The concentration of ATZ decreased significantly with the depth increasing, the detected depth of ATZ in groundwater was varied from 5 to 1100 m, and 70.27 % of the detected ATZ was distributed in the depth of 0–51.8 m. The detection rate of ATZ in most north regions lower than south regions in China, and ATZ with high concentration was mainly occurred in southern regions. ATZ is more likely to migrate into the groundwater in the water resource rich areas. The concentration of ATZ decreased with TDS increasing, 74.39 % of the ATZ was detected in groundwater with TDS concentration <1 g/L. The hydrochemical type of groundwater in ATZ-enrichment environment were mainly Ca-HCO3 and Mixed type. According to classification and regression tree analysis, the high ATZ detection rate were closely related with groundwater depth (<51.8 m) and high organic matter content.

Improving seedling recruitment and dryland restoration using a targeted fungicide seed coating

The success of seeding projects in dryland systems is sporadic, with failure primarily driven by low seedling emergence and survival. This sporadic nature is influenced by a litany of biotic and abiotic factors that act in synergy to reduce recruitment success. These factors include erratic seasonal weather patterns, competition, predation, plant material selection, and restoration strategies. While some events are unpredictable and uncontrollable, others may be mitigated through thoughtful deliberation. Pathogenesis from soil‐ and seed‐borne fungi is one form of predation that can decrease restoration success. Fungicide seed coatings are technologies used in the agriculture industry to mitigate fungal pathogens, yet these technologies are novel to wildland seeding. We evaluated the ability of a fungicide seed coating to improve bluebunch wheatgrass (Pseudoroegneria spicata) recruitment across a broad range of sites and determined how soil and climate affected seed treatments across six sites over 650 linear kilometers of sagebrush‐steppe habitat in the Great Basin, United States. Treatment effects varied by site; however, on average, the fungicide treatment increased germination by 16%, emergence by 42%, and juvenile plant establishment by 60%. Fungicide seed treatments had a greater effect on seedling emergence in soils with lower pH, reduced wet‐thermal accumulation during the winter, lower bulk density, and higher organic matter content. Most notably, the fungicide seed treatment resulted in higher plant establishment when emerged seedlings were exposed to longer periods of available soil moisture. Fungicide seed treatments can improve the establishment of native bunchgrasses, when soil and climate regimes are considered.

Management and Performance Analysis of Textile Effluent Treatment Plants in Laundries of The Local Productive Arrangement of Pernambuco

Objective: The present study aimed to assess 10 laundries for compliance with Brazilian legislation Theoretical Framework: The Local Productive Arrangement (APL) of Pernambuco plays a crucial role in job creation and economic growth in the state. However, the jeans beneficiation process consumes a significant amount of water and involves the use of various chemicals, which generate effluents with high organic loads, color, and toxicity. This has caused serious environmental problems. The issue is exacerbated during prolonged drought periods and by intermittent river flows, which reduce the natural self-purification capacity of the rivers. Method: A total of 334 influent and effluent samples were collected. All the laundries studied employed physicochemical treatment processes (flocculation followed by sedimentation). Results and Discussion: The WWTPs proved to be efficient in the removal of settleable solids, demonstrating that the coagulation and flocculation processes are effective for this purpose, even in scenarios with management deficiencies. On the other hand, poor operation of the treatment plants has resulted in other parameters, such as pH, oils, and greases, being out of compliance with current legislation. The efficiency in reducing BOD was highly inconsistent, with fluctuations ranging from over 90% efficiency to negative values, indicating significant operational issues. High concentrations of organic matter can compromise oxygen levels in the receiving bodies. It is essential to intensify monitoring and improve treatment processes to mitigate negative environmental impacts.

Exploring soil pedogenesis through frequency-dependent magnetic susceptibility in varied lithological environments

AbstractThe use of percent frequency-dependent magnetic susceptibility (χfd%) is well-established for detecting superparamagnetic (SP) components in fine-grained soils and sediments. This study employs χfd% as a direct indicator of pedogenetic processes in soils from the Moroccan Rif region. Three soil transects (T1, T2, and T3), each comprising four soil cores with depths reaching 100 to 120 cm, were sampled from distinct lithological formations within an area subject to moderate to intense erosion. A total of 272 soil samples were collected and analyzed using MS2 Bartington Instruments, providing values to calculate χfd% and identify ultrafine ferrimagnetic minerals (SP, &lt; 0.03 μm). In Quaternary fluvial terraces (T1) soils, approximately 60% of the samples indicate a mixture of SP, multidomain (MD), and Single Stable Domain (SSD) magnetic grains, while 30% contained coarser MD grains. Only 10% of the samples exhibit predominantly superparamagnetic (SP) grains. Soils on marly substrates (T2) showed 90% of samples with a combination of SP, MD, and SSD, and just 10% had SP grains. In contrast, soils from Villafranchian sandy deposits displayed χfd% values exceeding 10% in over 50% of samples, indicating that almost all iron components consist of SP grains. Physico-chemical analyses of the soils in profiles T1, T2, and T3 reveal distinct characteristics, including variations in clay content, organic matter, nutrient levels, and proportions of free and total iron. These results are important for understanding soil evolution and pedogenesis, with profiles T1 and T3 showing advanced development marked by high mineral iron, clay, and organic matter content. In contrast, profile T2 reflects a weak stage, influencing nutrient availability and contributing to overall soil dynamics in the respective profiles. The results of this study suggest that magnetic susceptibilities in these samples primarily originate from pedogenetic sources, revealing significantly advanced pedogenesis compared to T1 and T2 soils. The findings of this study align with previous research on soil erosion and degradation in the region, demonstrating that soils developed on terraces and marly substrates are more degraded and less stable than those on sandy substrates. This study underscores the utility of magnetic susceptibility as a rapid and effective indicator for initial soil assessment and gauging the degree of pedogenesis.

Characteristics of organic carbon in tobacco-growing soils with different pH

This paper deal with the analysis of the relationship between acidity and alkalinity with organic carbon structure and humus components of tobacco-growing soils in Tengchong city. Under the same level of organic matter and nutrient content, soils with different pH values in Tengchong city were selected for the investigation. Results showed that the HA/FA values of the soil with low organic matter content gradually decreased with increasing pH, indicating a higher content of active carbon components and a lower content of stable carbon components in the soils. In soils with high organic matter content, pH value showed a highly significant negative correlation with HA/FA and PQ values. With increasing acidity, HA/FA became higher, and humus components with high stability increased. At the same level of organic matter content, the infrared A2920/A1630 ratio gradually increased with increasing pH. It indicates that at a certain pH range and the same level of organic matter content, the stable humus component increases, and the soil pH value decreases. Bangladesh J. Bot. 53(3): 745-755, 2024 (September) Special

Biogas production from piloted wood-based bioethanol process using high-rate anaerobic treatment – Focusing for inhibition and improving biodegradability

To promote the bioeconomy, biorefineries with novel processes are developed. Biogas technology is commonly applied in biorefineries, and in this study, its feasibility for biogas production from wastewaters generated in a novel piloted wood-based bioethanol process was examined in expanded granular sludge bed reactors (EGSB). The novel wastewater was found to have high organic matter content and contained potentially inhibitory compounds. Wastewater was diluted with reactor effluent or tap water (control), and the proportion of wastewater in the feed was increased gradually to increase the organic loading rate. The wastewater was acidic (pH 4.2–4.6) and contained high concentrations of soluble chemical oxygen demand (sCOD 21–51 g/L) and sulfate (1–2.5 g/L). EGSB reactors had high sCODww (sCOD in the wastewater) removal of 74–77 % with OLRs up to 22 kg-sCODww/m3d and no inhibition either by the sulfide resulting from the high influent sulfate concentration or by the re-use of reactor effluent was seen. Integration of anodic oxidation (AO) to the EGSB reactor was studied in batch experiments increasing the biodegradability and total sCOD removal to 80–83 % and enhancing the methane production by 3 %. The results provide valuable information to support the implementation of anaerobic treatment plants as part of new industrial scale bioproduct production processes and encourages further studies on AO.

Enhanced remediation of real agricultural runoff in surface-flow constructed wetlands by coupling composite substrate-packed bio-balls, submerged plants and functional bacteria: Performance and mechanisms

Import of agricultural runoff containing nutrients considerably contributes to eutrophication of receiving water bodies. Surface-flow constructed wetlands (SFCWs) are commonly applied for agricultural runoff purification, but the performance is usually unsatisfactory. In this study, suspended bio-balls filled with zeolite and iron-carbon (Fe-C) composite substrates, submerged macrophyte (Ceratophyllum demersum) and functional denitrifying bacteria were collectively added into SFCW microcosms to enhance the remediation efficiency for real agricultural runoff with high nutrient concentrations and low content of bioavailable organic matter. The bio-ball added SFCWs achieved notably higher pollutant removal efficiencies (21.1%, 80.2% and 47.5% for chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP), respectively) than the control (COD: 6.9%, TN: 64.4%, TP: 27.9%), because of the versatile functions of filling materials for pollutant removal. C. demersum plantation (COD: 44.2%, TN: 82.8% and TP: 53.7%) and functional bacteria inoculation (COD: 51.8%, TN: 85.8% and TP: 55.1%) further enhanced the efficiency of the SFCWs for agricultural runoff remediation. Bio-ball addition and C. demersum plantation significantly increased the humification degree and reduced the molecular weight of dissolved organic matter (DOM) in the agricultural runoff. Moreover, the two intensification measures also notably reduced organic and nitrogen contents in the wetland sediment. Remarkable distinction in bacterial community distribution patterns was observed in the SFCW sediment and filling substrates in bio-balls. Keystone genera including Clostridium_sensu_stricto_1 and Bacillus in the zeolite, Sphingomonas and Exiguobacterium in the Fe-C substrates and Sediminibacterium in the sediment might be critical for agricultural runoff remediation in the SFCW microcosms. The study highlights a high potential of the intensified SFCWs by these coupling measures for agricultural runoff remediation.

Cretaceous Petroleum System Elements in the Komombo Basin, Egypt

The petroleum system elements in the Komombo Basin have not yet been fully assessed. This study aims to evaluate source rocks, reservoirs, and seals within the basin by integrating 2D seismic profiles, and well logs together with geochemical, core, and petrophysical data. Four source rocks are identified within the Cretaceous shale intervals of the B member of the Six Hills, upper Maghrabi, Quseir, and Dakhla formations. The quality of the B member, upper Maghrabi, and Quseir source rocks is good to very good, while the Dakhla Formation demonstrates good to excellent quality. Geochemical characteristics vary across the basin, with higher kerogen quality and thermal maturity observed in the depocenter compared to the flanks. Four reservoirs are recognized in the basin, including the A member, C member, sandstones within D-G members of the Six Hills, and Sabaya-Maghrabi formations. The A member reservoir demonstrates moderate reservoir quality, while the C member reservoir displays fair quality. Numerous sandstones with 15-25% porosity values are observed within the D-G members. The Sabaya-Maghrabi reservoir generally exhibits good to very good quality and is characterized by high porosity and varying permeability. Due to their high organic matter content, the Dakhla and Quseir formations show potential as unconventional reservoirs. Several shale units within the Komombo Basin serve as potential seal rocks. These include the B member of the Six Hills, Abu Ballas, upper Maghrabi, and Taref formations, as well as intra-formational shales within the reservoir rocks. Seismic interpretation indicates faults are the predominant trapping mechanism in the basin.

The tectonostratigraphic evolution of a Miocene half-graben, Kerio Valley Basin, East African Rift of Kenya: analysis of a 3 km thick volcano-sedimentary succession

The Kerio Valley Basin is a classic half-graben within the Eastern Branch of the East African Rift System, though to date its tectonostratigraphic evolution has only been interpreted through an incomplete stratigraphic record exposed along structural highs. This study examines a 3 km thick, volcano-sedimentary succession recorded within a hydrocarbon exploration well, Cheptuket-1, located within the hanging wall of the Kerio Valley Basin. A suite of silicic extrusive volcanic and volcaniclastic rocks are also recorded, calibrated by a dense collection of thin-sections from 84 side-wall cores. These volcanic rocks include phonolite lava flows. Through documentation of the well stratigraphy and integrating newly acquired 40 Ar/ 39 Ar age dates from outcrop, we detail a substantially revised, simpler tectonostratigraphic evolution of this basin. Cheptuket-1 penetrated a Middle Miocene to recent stratigraphic succession, bottoming in metamorphic basement, likely through a fault plane. Several phases of lake development are elucidated, including both pre- and syn-mechanical rifting, with the latter phase containing beds exhibiting high organic matter content. This study ultimately represents a rare insight into a near complete rift-basin hanging-wall succession, as well as detailing a workflow for characterising mixed volcanic and sedimentary successions.

Integrated processes for olive mill wastewater treatment and its revalorization for microalgae culture.

The olive oil industry generates 30 million cubic meters of olive mill wastewaters (OMWWs) annually. OMWWs are a major environmental concern in the Mediterranean region due to their high organic matter content, suspended solids, unpleasant odor, and dark color. The application of primary treatments such as coagulation-flocculation, adsorption, and hybrid systems combining coagulation-flocculation with adsorption has enabled to remove part of the organic matter, color, turbidity, and growth-inhibiting compounds from OMWWs. Among these methods, the hybrid system combining activated carbon and chitosan has proven to be the best removal efficiency. Subsequently, secondary treatment involving the cultivation of Chlorella sp. on OMWWs pretreated with chitosan achieved the highest maximal specific growth rate (0.513 ± 0.022day⁻1) and biomass productivity (0.621 ± 0.021g/L/day). Notably, the fatty acids (FA) profile produced by Chlorella sp. cells grown under these conditions differed, underscoring the potential of OMWWs as a microalgal growth medium. This innovative approach not only addresses environmental issues but also opens new avenues for sustainable bioproducts.

Simulation and optimization of cheese whey additive for value-added compost production: Hyperparameter tuning approach and genetic algorithm

Cheese whey is a difficult and costly wastewater to treat due to its high organic matter and mineral content. Although many management strategies are conducted for whey removal, its use in composting is limited. In this study, the effect of cheese whey in the composting of sewage sludge and poultry waste on compost quality and process efficiency was investigated. Also, valid and consistent simulations were developed with Gaussian Process Regression (GPR), Support Vector Regression (SVR), and Neural Network Regression (NNR) Machine Learning (ML) algorithms. The results of all physicochemical parameters determined that 3% of cheese whey addition for both feedstocks improved the composting process's efficiency and the final product's quality. The best results obtained through hyperparameter tuning showed that Gaussian Process Regression (GPR) was the most effective modeling tool providing realistic simulations. The reliability of these simulations was verified by running the GPR process 50 times. MdAPE demonstrated the validity and consistency of the created process simulations. Moreover, a genetic algorithm was used to optimize these dependent simulations and achieved almost 100% desirability. Optimization studies showed that the effective cheese whey ratios were 3.2724% and 3.1543% for sewage sludge and poultry waste, respectively. Optimization results were compatible with the results of experimental studies. This study provides a new strategy for the recovery of cheese whey as well as a new perspective on the effect of cheese whey on both physicochemical parameters and composting phases and the modeling and optimization processes of the results.

Differential hydrocarbon generation characteristics of organic matter with green algae and cyanobateria origins in the Permain Lucaogou Formation of the Santanghu Basin

Organic-rich fine-grained rocks are key carriers of unconventional oil and gas resources, making it crucial to understand their hydrocarbon generation and evolution characteristics. This study examines the fine-grained rocks of the second member of the Lucaogou Formation (P2l2) in the Tiaohu and Malang Sags of the Santanghu Basin, focusing on how different organic matter (OM) backgrounds - primarily green algae and cyanobacteria - affect hydrocarbon generation and crude oil properties. Kinetic analysis and hydrous pyrolysis experiments on shales rich in green algae, cyanobacteria, and their mixtures revealed that green algae - derived OM requires lower activation energy to initiate hydrocarbon generation, results in an earlier oil generation peak, and has a broader oil window. Conversely, cyanobacteria - derived OM needs higher activation energy to start hydrocarbon generation, has a later oil peak, and a more concentrated generation period. These findings led to two models: the "green algae origin - early hydrocarbon generation - early oil peak - broad oil window model" and the "cyanobacteria origin - late hydrocarbon generation - late oil peak - concentrated oil generation model." Correlation analysis showed that aromatic hydrocarbons, resins, and asphaltenes significantly degrade crude oil quality. Hydrous pyrolysis experiments indicated that the heavy component content (aromatic hydrocarbons + resins + asphaltenes) in liquid hydrocarbons follows the order: residual oil > absorbed oil > expelled oil, with content initially increasing and then decreasing with maturity, and the color change of liquid hydrocarbons in dichloromethane reflects heavy component content changes effectively. Calculations of density and viscosity of liquid hydrocarbons, based on heavy component content and crude oil properties, were compared with the longitudinal distribution of crude oil properties in the study area. Results show that the hydrocarbon generation characteristics of green algae and cyanobacteria control crude oil properties, highlighting significant intra-source differentiation in the P2l2 shale and validates the phase separation approach in hydrous pyrolysis experiments. The P2l2 shale, with its high OM content and substantial hydrocarbon generation, holds great potential for shale oil exploration, but both reservoir quality and crude oil property evolution under different OM backgrounds should be considered when selecting favorable areas.

Anaerobic biodegradation of real pharmaceutical-grade lactose manufacturing wastewater in a modified Internal Circulation Reactor

Pharmaceutical-grade lactose (PL) manufacturing generates wastewater containing high concentrations of biodegradable organic matter. In the absence of a suitable alternative, industries handle such concentrated streams by completely evaporating the entire stream and disposing of water-soluble solid residue in a landfill. Such a process is energy-intensive, and nothing useful is recovered from the stream. This study demonstrates the efficient and sustainable anaerobic biodegradation of real PL wastewater using a lab-scale internal circulation reactor (ICR) combined with an external recirculation system. The effects of feed Chemical Oxygen Demand (COD) concentration, organic loading rate (OLR), and hydraulic retention time (HRT) on COD removal efficiency, methane production, and the volatile fatty acids/alkalinity (VFA/ALK) ratio were evaluated. Under the highest feed COD concentration of 60,000mg/L, OLR of 4.5kg/m³∙d, and HRT of 13.33 days, the system achieved an average COD removal efficiency of 93.8% with methane production of 25.2L/d (specific methane generation of 0.32L/g CODremoved). By increasing the up-flow velocity from 0.044m/h (without external recirculation) to 1.5m/h (with external recirculation), COD removal improved from 63.6% to 93.4%, and methane production increased from 7.5L/d to 14L/d. The kinetics of COD removal fitted well in the modified Stover-Kincannon model (R2 = 0.99). A unique finding of this study is that the loose anaerobic sludge became granulated after 120 days, with 50% of the granules having diameters ≥ 2.0mm. The results of this study establish anaerobic biodegradation as a suitable treatment option for PL wastewater, thereby achieving UNSDG 6 (Clean Water and Sanitation) and 7 (Affordable and Clean Energy).

Waste cigarette filters-based polymer blends membrane for filtration of high loaded natural organic matter river water

Waste cigarette filter (WCF) is one of the most common wastes found in the environment. Cigarette filters contain up to 96% cellulose acetate (CA), which can be used as a material for membrane fabrication. However, the CA-based membrane from WCF posed a weak mechanical property (brittle). Therefore, the objective of this work is to improve mechanical property of CA-based membrane from WCF by preparing blend membranes with polyvinylidene fluoride (PVDF) polymer and evaluate their performance for filtration of real river water containing high natural organic matter (NOM) concentrations. The variations of WCF and PVDF used were 100:0, 75:25, 50:50, 25:75, and 0:100. The membranes were then characterized to determine the morphology, pore size and pore size distribution, hydrophilicity, mechanical properties, and filtration performance of the membrane using clean water and river water. The SEM test results showed the presence of spherulites on the surface of the blend membrane, indicating that crystallization occurred during membrane formation. The spherulites resulted in smaller pore size, narrower pore size distribution, higher hydrophilicity, and mechanical properties. Meanwhile, the filtration test results showed that blend membranes produced higher permeability compared to pristine WCF, PVDF, and commercial-based CA membranes, where the result of river water permeability was in the range of 875–1062.5 L/m2.h.bar. The membrane fouling formation was aligned well with the result of permeability and is dominated by irreversible fouling formation from the dynamic cake layer built on the membrane surface, with NOM rejections of 26.6–33.8%, suggesting the need for further developments.

In situ treatment of contaminated soil using persulfate activated by sulfidated zero-valent iron

Soil contamination with hazardous substances like phenol poses significant environmental and health risks. In situ soil mixing can be a promising technological solution to this challenge. A persulfate and sulfidated zero-valent iron (S-ZVIbm) system for remediating contaminated soil was developed and tested to be suited to in situ soil mixing. S-ZVIbm was synthesized using a ball mill process, and the optimal sulfur to iron molar ratio for effectively removing phenol from soil removal without pyrophoric risks was 0.12. Soil slurry experiments were performed, and the best phenol oxidation results (high stoichiometric efficiency and sustained oxidation after mixing) were achieved at a persulfate to S-ZVIbm molar ratio of 2:1 and a persulfate to phenol molar ratio of 8:1. A high organic matter content of the silty clay fraction of the soil strongly suppressed persulfate activation, so suppressed phenol removal and increased persulfate consumption. Electron spin resonance and radical scavenging tests confirmed that hydroxyl and sulfate radicals were present during the degradation of phenol. While sulfate radicals predominantly facilitated degradation in the soil, both sulfate and hydroxyl radicals were crucial in the aqueous phase in the absence of soil organic matter. In situ soil mixing simulation tests indicated that the persulfate and S-ZVIbm doses and the mixing rate and duration strongly affected the efficacy of the system, and the optimal conditions for phenol removal were determined. The results indicated that the persulfate/S-ZVIbm system could be tuned to achieve sustained persulfate activation and to remediate contaminated soil employing in situ soil mixing technique.

Sustainable agriculture through qanat systems in Karabakh: Water and soil characteristics in the context of climate change

This study investigates the water quality and soil characteristics associated with qanat systems in the Cebrail district of the Karabakh region, Azerbaijan. Qanat systems, traditional underground channels designed for water transport, play a crucial role in providing reliable water sources for drinking and irrigation. Water and soil samples were collected from seven qanat systems and analyzed for various physicochemical properties. Water quality parameters included pH, electrical conductivity, hardness, mineralization, and concentrations of calcium, magnesium, sodium, and other ions. Soil analyses focused on pH, electrical conductivity, organic matter content, salinization degree, and the presence of key ions like sulfate and nitrate. The results indicated that qanat water is generally of high quality, with pH levels suitable for both drinking and irrigation. However, some qanat systems exhibited high electrical conductivity and mineralization levels, suggesting potential salinity issues for sensitive crops. Soil samples showed favorable conditions for agriculture, with good pH levels, low salinity, and high organic matter content. The analysis revealed a significant interaction between water quality and soil characteristics, emphasizing the importance of integrated management practices. In the context of climate change, the sustainability of qanat systems is critical. Recommendations include regular monitoring of water and soil quality, soil amendments to mitigate salinity, efficient irrigation techniques, and the use of climate-resilient infrastructure. This study underscores the importance of qanat systems in arid and semi-arid regions and provides practical recommendations for sustainable land and water resource management, enhancing the socio-economic well-being of local communities.

Effect of Biochar on Composting of Cow Manure and Kitchen Waste

Composting is a common method for managing organic waste and creating nutrient-rich soil amendments. Recently, biochar, a carbon-rich material from biomass pyrolysis, has been noted for potentially improving composting. This study examines the impact of adding biochar to compost made from cow manure and kitchen waste through a controlled lab experiment. The treatments were labeled as CMX (cow manure), KWX (kitchen waste), and CMKWX (both) with X being the percentage of CM, KW, and CMKW minus that of biochar in the mixture. Key parameters such as temperature (T), pH, and electric conductivity (EC) were tracked during the composting processes, and the final composts were analyzed for total nitrogen (N), available nitrogen (AN), total phosphorus (TP), available phosphorus (AP), total potassium (TK), organic carbon (OC), calcium (Ca2+), magnesium (Mg2+), and organic matter (OM). The results showed that adding less than 10% biochar influenced composting positively. Specifically, 5% biochar amendment led to higher thermophilic temperatures (45–57 °C) and stable pH levels (6.3–8.7) compared to controls. However, biochar did not significantly enhance EC, which peaked at 1.78 dS/m in both the control and 5% biochar treatments. Nutrient analysis revealed that biochar increased Ca2+ (13.62 meq/g) and Mg2+ (5.73 meq/g) retention in CM composts (CM85 and CM100). The highest OM content was 16.84% in CM90, while the lowest was 3.81% in CM95. Higher OM negatively affected TN, with CM treatments having more OM and KW treatments having more TN. TP and TK were higher in control treatments without biochar. This study highlights the benefits of integrating biochar with organic waste for enhancing compost nutrient profiles and soil fertility. It was observed that the more diverse the compost feedstock, i.e., CMKW, the higher the nutrient content for treatments containing less than 10% biochar.

The role of environment descriptors and seagrass biometrics in shaping macrobenthic assemblages’ structure in intertidal Zostera noltei meadows

The present study describes macroinvertebrate assemblages in three Zostera noltei meadows, following a salinity gradient along the Aveiro lagoon (Portugal). The main environmental descriptors and Z. noltei biometrics were studied to provide a model of the multivariate macroinvertebrate assemblage structure. The macroinvertebrate assemblage structure in the meadow close to the lagoon opening was significantly different. This could be explained by its higher organic matter content and salinity values. Our model highlighted that 72% of the variation on macroinvertebrate assemblage structure was explained by the studied variables, being organic matter, salinity and sediment median grain size the most relevant factors. Moreover, the number of Z. noltei shoots, and cover of the invasive species Agarophyton aff. vermiculophyllum were also significant. The strong relationship between macroinvertebrates, environmental descriptors and Z. noltei biometrics validates the usefulness of macroinvertebrates as indicators of the seagrass condition in intertidal environments. This study provides baseline data that will be crucial to detect anthropogenic disturbances and preserve Z. noltei meadows, including their associated biodiversity. These data will also allow focusing on certain environmental factors and Z. noltei biometrics that have proved shaping the macroinvertebrate assemblages’ structure.