Search Results (2,406)

Inner Mongolia has the largest sheep population among China’s provinces, resulting in the production of a substantial amount of sheep manure. If left untreated, this manure can contribute to environmental pollution. However, sheep manure serves a dual purpose: it can be both a pollutant and a valuable source of organic fertilizer. Consequently, there is an urgent need to address the environmental issues arising from manure accumulation and its unused status. In this paper, a viable solution is proposed: the conversion of manure into fertilizer through a composting unit incorporating high-temperature aerobic fermentation technology. This unit, tailored for small farms and individual farmers, integrates critical functions such as ventilation, heating, and turning. Additionally, it boasts excellent thermal insulation, enhancing composting efficiency and enabling precise control over fermentation conditions. This design mitigates heat loss and accelerates maturation, addressing common challenges in traditional composting. The design process encompassed both equipment construction and control systems, with a primary focus on compost fermentation and aeration heating. The components were carefully designed or selected based on theoretical analysis and subsequently validated using simulation software, including EDEM and Fluent. The control system seamlessly integrates a touch screen interface, PLC programming, and control circuits to manage air pumps and electric heaters in response to changes in temperature and oxygen concentration. Furthermore, it controls the motors during the recovery phase. A comprehensive performance evaluation was conducted, revealing notable improvements. Under artificially heated conditions, the maximum temperature of the compost increased by approximately 20 °C, the composting cycle was reduced by roughly 4 days, and the seed germination index (GI) rose by about 9% when compared to natural fermentation. Thus, this device significantly accelerates composting and improves fertilizer quality by increasing the decomposition rate. Full article

Solid waste disposal methods within indigenous communities present unique challenges and opportunities for sustainable development. However, the current knowledge on solid waste management focuses on formal waste collection systems, neglecting the practices and sustainability aspects of solid waste management in indigenous communities. Thus, it becomes imperative to undertake research studies that evaluate the sustainability of these practices as they play a pivotal role in ensuring sustainable development. The current study systematically evaluates the views and judgments associated with the sustainability aspects of indigenous waste management practices in the rural communities of South Africa using the Analytic Hierarchy Process (AHP) model. The data analysis was carried out using the AHP model. The findings of this study showed that the rural communities of Bushbuckridge Local Municipality prioritize the sustainability of the environment (weight: 0.590) over the economic (weight: 0.240) and social sustainability (weight: 0.165) based on the AHP evaluative framework. The validity of the priorities was tested through the computed degree of consistency (<10%) and an eigenvalue of 5.107. Furthermore, according to the assessment in the current study, the AHP evaluative framework dominantly prioritizes the sub-criteria of environmental sustainability (composting) at a responding rate of over 70% almost across all indigenous communities except for Acornhoek (30%), Casteel (25%), and Mambumbu (24%). Likewise, the sub-criterion of social sustainability, which is associated with communal cleaning labor, was found to be of extreme importance (60%), outperforming taboos (10%) that are anchored in cultural and spiritual beliefs. With a response rate > 50%, waste trading proved to be of economic efficacy. Using the AHP model to evaluate the sustainability aspects associated with indigenous solid waste management practices addresses a substantial gap in the comprehension of the role of indigenous knowledge towards sustainability in the discipline of solid waste management. However, it also offers a valuable sustainability perception that is associated with indigenous waste disposal methods that local governments and policymakers should include for consideration in integrated waste management plans. This can lead to the development of waste disposal programs that are well-coordinated and in accordance with indigenous sustainable waste management practices that advance the circular economy and promote environmental protection. Full article

The circular economy with compost fertilization is included in the sustainable orchard paradigm, creating a holistic production ecosystem. Modern orchards are mostly intensive and super-intensive, requiring different rootstocks. This research presents the response to compost fertilization of two specific pear rootstocks (quince ‘CTS 212’ and ‘Farold^® 40’) and own-rooted trees, analyzing six resistant cultivars in a circular production system. The dynamic of nitrogen and carbon concentration in leaves, soil respiration coefficient, the evolution of the fruit maturity stage in the field, and some biometric parameters such as trunk cross-section area, the annual vegetative growth, and fruiting shoots annual number were analyzed. The results highlighted that compost fertilization led to increased leaf nitrogen concentration over the first two years while carbon concentration remained relatively stable. Rootstock and compost fertilization influenced the fruit maturity dynamic, but a single pattern was not identified. Quince, as pear rootstock, expressed a higher sensitivity to compost application; the biometric parameters, such as trunk cross-section area, and almost all cultivars’ annual vegetative growth were higher than the controls’. Positive output can lead to future model upscaling in farms and households. Full article

This study focuses on the physiological response of lettuce grown on Technosols designed for the remediation of soils polluted by potentially harmful elements (PHEs: As, Cd, Cu, Fe, Pb, and Zn). Lettuce plants were grown in five treatments: recovered (RS) and polluted soil (PS) as controls, and three Technosols (TO, TS, and TV) consisting of 60% PS mixed with 2% iron sludge, 20% marble sludge, and 18% organic wastes (TO: composted olive waste, TS: composted sewage sludge, and TV: vermicompost of garden waste). The main soil properties and PHE solubility were measured, together with physiological parameters related to phytotoxicity in lettuce such as growth, photosynthetic capacity, oxidative stress, and antioxidant defence. All Technosols improved unfavourable conditions of PS (i.e., neutralised acidity and enhanced OC content), leading to a significant decrease in Cd, Cu, and Zn mobility. Nevertheless, TV was the most effective as the reduction in PHEs mobility was higher. Furthermore, lettuce grown on TV and TO showed higher growth (+90% and +41%) than PS, while no increase in TS. However, lower oxidative stress and impact on photosynthetic rate occurred in all Technosols compared to PS (+344% TV, +157% TO, and +194% TS). This physiological response of lettuce proves that PHE phytotoxicity is reduced by Technosols. Thus, this ecotechnology constitutes a potential solution for soil remediation, with effectiveness of Technosols depending largely on its components. Full article

This study investigated the microbiological and parasitic quality of sewage sludge treated in drying beds in Algeria, aiming to contribute to a better understanding of the factors influencing sludge safety for potential agricultural applications in the Algerian context. The research focused on various sludge types (liquid, semi-solid, and solid) and their behavior across different seasons. Standard microbiological methods were employed to quantify total coliforms, fecal streptococci, E. coli, and Clostridium. Controls were implemented to ensure accuracy, with positive controls validating detection methods using known quantities of microorganisms and parasites, while negative controls confirmed the absence of contamination in the testing environment. Parasitic contamination was assessed through microscopic examination for protozoa and helminths. Results revealed substantial variation in microbial concentrations across sludge types and seasons. Liquid sludge, particularly during summer, exhibited the highest levels of total coliforms (up to 7.021 log10) and E. coli (up to 6.049 log10), while solid sludge showed lower counts. Seasonal trends indicated increased microbial levels during warmer months. Parasitic contamination was prevalent in 81% of samples, with protozoan cysts (e.g., Giardia intestinalis and Endolimax nanus) and helminth eggs detected. Despite reducing microbial loads, drying processes alone were insufficient, leaving significant contamination. Enhanced protocols are needed, such as longer drying periods, chemical disinfectants, or advanced technologies like anaerobic digestion or composting. This highlights the need for locally adapted treatment strategies. Furthermore, this research provides specific recommendations for improving sewage sludge management practices in Algeria, taking into account the unique environmental and agricultural context of the country. Full article

ASGM in the Chocó region (Colombian Pacific) has generated abandoned puddles with concentrations of Hg; however, these sites can generate ecosystem services from contaminated biomass with a circular economy approach. (1) Background: The plant biomass contaminated with Hg from these puddles could be used to produce compost as a bioremediation strategy and as an alternative to generate ecosystem resources (organic fertilizer) with nature-based solutions, representing a circular economy approach and sustainable management of contaminated biomass. (2) Methods: Six treatments were established to produce compost; closed-system plastic composters were used, with a capacity of 15 kg of biomass and organic waste, consisting of contaminated and uncontaminated biomass of macrophytes with Hg and fruit and vegetable waste (fruit and vegetable waste, pruning waste, and poultry manure). The concentrations of As and total and bioavailable Hg were monitored during the composting process by atomic absorption spectroscopy and so were properties such as pH; electrical conductivity; temperature; CO, TN, S, and SiO₂ contents; and C/N ratio. (3) Conclusions: The concentrations of bioavailable Hg during the composting process were between 658.1 and 1.2 µg/kg, decreasing in the following order: T-2 > T-3 > T-1 > C-3 > C-2 > C-1. Composting in the treatments was shown to be an efficient bioremediation technique, as all of the treatments reduced the bioavailability of Hg to below 1.5%, and the physicochemical properties of pH (r: −0.3675; p < 0.007) and %S content (r: −0.6303; p < 0.0025) showed a significant moderate negative correlation with bioavailable Hg concentrations, playing a crucial role in reducing the bioavailability of Hg during the purification process of composting. The results show that all treatments significantly reduced Hg bioavailability below 1.5%; however, T-2 proportionally showed the highest reductions during the process. Compost production was proven to be a sustainable strategy for the management of biomass contaminated with mercury, which is very important for recovering ecosystem services in communities. Full article

Thise study investigated the effect of three lignocellulolytic thermophilic Bacillus strains (F11, Q1, and FP4) on lignocellulose degradation, enzymatic activities, and microbial community structure in composting. The lignin degradation rate reached 36% in the presence of the inoculant, the hemicellulose degradation rate ranged from 43% (F11) to 51% (Q1), and cellulose degradation rates reached 57% in F11 and in FP4, which were significantly higher than the control (CK). The inoculation treatment could explain 28% of the lignin degradation for all three strains. The contribution of FP4 to hemicellulose and cellulose degradation was 30% and 20%, respectively. Compared to CK, lignin peroxidase activity in the water extract of the compost had increased by 66~145% for inoculation treatments, and manganese peroxidase and laccase activity increased by 114% and 78% for Q1. The inoculation stimulated the growth of indigenous bacteria with stronger lignocellulolytic enzyme-producing ability; such shifts in microbial communities were most likely responsible for the improved lignocellulose degradation. Full article

This study investigated treatment methods for urban wastewater sludge, specifically examining natural drying over five years, accelerated freeze–thaw–drying cycles, and composting with and without a zeolite additive. The findings reveal that composting effectively stabilized the sludge while retaining essential nutrients crucial for agriculture. Notably, with the addition of 2% zeolite by total mass, approximately 40% of the total nitrogen was preserved. Adequate aeration during composting maintained acceptable levels of phosphorus compounds, with the phosphorus content expressed as P₂O₅ showing significant retention compared with the natural drying methods. Composting also demonstrated a substantial reduction in petroleum hydrocarbon concentrations, which decreased from 30 mg/kg to 3 mg/kg, thereby showcasing its potential for processing contaminated sludge. The inclusion of zeolite enhanced the nitrogen retention by an additional 10–20% compared with the composting without zeolite, aligning with previous studies on its effectiveness. While composting and thermal treatments, like accelerated freeze–thaw cycles, influenced the physical properties of the sludge—such as reducing the moisture content and altering the volatile substance concentrations—they did not significantly affect the heavy metal levels. Natural drying over five years resulted in reduced metal quantities, which possibly reflected changes in the wastewater characteristics over time. Given that the heavy metal concentrations remained largely unchanged, additional treatment methods are recommended when the initial sludge contains high levels of these contaminants to ensure the safe use of the final product as fertilizer. This study underscored the significant role of biochemical and microbiological processes during composting and natural drying in transforming sludge properties. Future research should focus on establishing upper contamination thresholds and exploring microbiological safety measures to enhance the viability of sludge reuse in agriculture, balancing nutrient preservation with environmental safety. Full article

In general, agricultural productivity in Angola is low due to the limited awareness among stakeholders regarding sustainable development strategies (DSs) and good agricultural practices (GAPs) that could be adjusted to local crops, soil types, and climatic conditions. A structured approach was followed to develop a systematic literature review (SLR) that can address this gap by examining how DSs and GAPs may be adapted for Angola’s context to encourage sustainable agricultural development. Key steps included the selection and exclusion of literature from primary scientific databases based on specific screening indicators such as the publication date, language, relevance to DSs and GAPs, and geographic focus on developing or developed nations with comparable agricultural challenges. The initial search resulted in 11,392 articles, of which 4257 met the primary selection criteria. After further screening for relevance and availability, 98 articles were shortlisted, and 15 studies were ultimately included for in-depth analysis. This strict screening process ensured the inclusion of studies most applicable to Angola’s agricultural context. The key research findings indicate that certain DSs and GAPs have high adaptability potential for Angola. The findings emphasise practices such as drip irrigation and inorganic fertilisation, which are widely implemented in both developed and developing countries due to their efficiency in resource-limited environments. Additional strategies, such as water management systems, organic composting, and agroforestry practices, demonstrate significant potential to enhance soil fertility, water efficiency, and crop resilience against climate variability. By identifying these practices and strategies, this study provides a basic framework for policymakers in Angola to develop targeted implementation guidelines, fostering sustainable agricultural growth and resilience in the face of climatic challenges. Thus, this review contributes to the scientific and practical understanding of sustainable agriculture in developing countries, offering critical insights that support Angola’s efforts to achieve greater self-sufficiency and economic stability through sustainable agricultural practices. Full article

Sustainable development is one of the main directions of modern agriculture. First of all, sustainability in the agricultural sector can be achieved through the possible abandonment of traditional mineral fertilizers. Many decades of using these fertilizers have led to the degradation of arable soils and to soil and environmental pollution. As a result, this causes reductions in yields and the environmental quality of agricultural products and affects the health of the population. An alternative to traditional mineral fertilizers may be the use of innovative organomineral fertilizers obtained from local resources. These include manure, humus, compost, sediments, etc. In recent years, fertilizers obtained from the sapropels of the bottom sediments of lakes have become widespread. Their distinctive feature is the environmental friendliness and completeness of the content of chemical elements and substances necessary for the development and growth of plants. In addition, the methods of obtaining and applying these fertilizers allow us to talk about their effectiveness in use. The range of applications of these fertilizers is diverse, from use in the form of a dry extract applied directly to the soil to the use of liquid suspensions used at various stages of processing and from pre-sowing seed treatment to watering and spraying plants at different periods of vegetation. Moreover, an important aspect is the research work on the variational use of sapropel fertilizers on different crops, with different methods of production and concentrations and at different stages of processing. This publication contains the results of a study of the effect of the obtained innovative sapropel fertilizer on productivity, wheat grain quality, and economic efficiency (Triticum aestivum L.). To identify the optimal concentration of sapropel extract, laboratory studies were carried out to determine the germination energy and germination of wheat seeds of different varieties when they were soaked in various concentrations: 0.4, 0.8, 1.2, 1.6, and 2.0 g/L. The best indicators of germination energy and germination of wheat seeds during treatment with the extract were obtained at a concentration of 1.2 g/L. The research was conducted at an accredited variety testing laboratory. A field experiment was conducted in the fields of the agrobiological station of North Kazakhstan University named after Manash Kozybayev. The treatment of the seeds was carried out by soaking them in sapropel extract to evenly distribute the substance. The scheme of the field experiment included the option of using foliar treatment with a solution of sapropel extract at the tillering stage. As a result of the application of the obtained extract in the field, environmental and socio-economic efficiency was noted. The conducted field studies note its positive effect and effectiveness on the morphological, qualitative, and quantitative indicators of the wheat harvest. In the areas where wheat seeds were pretreated, as well as where foliar treatment with the resulting sapropel suspension was carried out, the best yield indicators were revealed. In these variants of the experiment with pre-sowing and pre-sowing and foliar treatment with the sapropel extract solution, the yield was 3.63 and 3.81 tons per hectare, respectively. The introduction of sapropel extract at the stage of seed treatment before sowing, as well as foliar processing of wheat at the tillering stage, will increase the efficiency and profitability of the agricultural industry and obtain a synergistic effect in the form of socio-economic efficiency and environmental safety of production. In our opinion, this will contribute to the development of sustainable agriculture and the production of environmental products. Full article

The rising demand for climate change mitigation has brought attention to agricultural systems focused on carbon farming and reducing emissions. Composting food wastes and livestock manure not only mitigates environmental concerns but also boosts soil fertility and crop yields as an alternative fertilizer. In this experiment, we investigated the effects of different fertilizer types (chemical and organic waste compost) and crop rotations (rice–fallow, rice–Italian ryegrass, and rice–potato) on rice production, nitrogen use efficiency, and soil carbon stocks. In this experiment, soil carbon and nitrogen retention were more influenced by compost nutrient levels than by crop rotation types. Overall, as the nitrogen levels increased, the rice yields improved with both chemical and organic waste fertilizers. Among the crop rotations, the rice–Italian ryegrass rotation showed a higher nitrogen use efficiency. Optimal fertility levels, balancing nitrogen use efficiency, yield, and soil carbon were observed between 523 and 582 kg N ha⁻¹ when combined with specific crop rotations. Moreover, soil total carbon and soil total nitrogen varied among crop rotation systems. Our results indicate that organic waste compost can be a potential alternative to chemical fertilizers, while crop rotations offer a viable approach for maximizing the environmental benefits. Full article

This research explores how different organic waste transformation methods influence the production of humic substances (HSs) and their impact on soil quality. Using olive and orange wastes as substrates, the study compares vermicomposting, composting, and anaerobic digestion processes to determine which method produces the most humic-substance-rich products. The characterization of HSs in each product included analyses of total organic carbon (TOC), humic and fulvic acid content, humification rate, humification degree, and E4/E6 ratio, with HSs extracted using potassium hydroxide (KOH) and analyzed via Diffuse Reflectance Infrared Fourier-Transform (DRIFT) spectroscopy to assess structural complexity. The results revealed that the chemical composition of the input materials significantly influenced the transformation dynamics, with orange by-products exhibiting a higher humification rate and degree. Vermicomposting emerged as the most efficient process, producing fertilizers with superior humic content, greater microbial biodiversity, and enhanced cation exchange capacity, thus markedly improving soil quality. Composting also contributed to the stabilization of organic matter, albeit less effectively than vermicomposting. Anaerobic digestion, by contrast, resulted in products with lower levels of HSs and reduced nutrient content. Aerobic processes, particularly vermicomposting, demonstrated the most rapid and effective transformation, producing structurally complex, stable humus-like substances with pronounced benefits for soil health. These findings underscore vermicomposting as the most sustainable and efficacious approach for generating HS-rich organic fertilizers, presenting a powerful alternative to synthetic fertilizers. Furthermore, this study highlights the potential of organic waste valorization to mitigate environmental pollution and foster circular economy practices in sustainable agriculture. Full article

The unscientific disposal of agricultural solid waste introduces more antibiotics and other pollutants into the environment. Composting, as an environmentally friendly solid waste disposal method, can be used as a green way to degrade antibiotics, and conditioners can regulate the physicochemical indicators of the composting process. This article investigates the removal mechanism of tetracycline antibiotics (TCs) during the composting process by adding different regulators (biochar, zeolite, and biochar + zeolite). The results showed that the conditioning agent could significantly improve the removal efficiency and removal rate of TCs in compost. Among them, the addition of the zeolite group had the highest degradation rate of TCs, which were 91.39% (Tetracycline), 97.18% (Chlortetracycline), and 95.68% (Oxytetracycline). The combination of biochar and zeolite conditioning agents effectively minimized the migration of TCs into the soil. According to the findings of the artificial neural network model, it was determined that TCs exhibited the highest sensitivity to biochar + zeolite modulators at 31.28%. Conditioners influenced the removal of TCs in compost by impacting their physicochemical properties and microbial community structure. We isolated and domesticated a suitable microbial preparation that promotes the degradation of TCs, including Acinetobacter pittii, Stenotrophomonas maltophilia, Lactobacillus reuteri, Pseudomonas putida, and Trichosporon dohaense. Full article

Soil salinization is considered a major global environmental problem due to its adverse effects on agricultural sustainability and production. Compost is an environmentally friendly and sustainable measure used for reclaiming saline–sodic soil. However, the responses of the physiological characteristics of alfalfa and the structure and function of rhizosphere fungal communities after compost application in saline–sodic soil remain elusive. Here, a pot experiment was conducted to explore the effect of different compost application rates on soil properties, plant physiological traits, and rhizosphere fungal community characteristics. The results showed that compost significantly increased soil nutrients and corresponding soil enzyme activities, enhanced leaf photosynthesis traits, and ion homeostasis compared with the control treatment. We further found that the rhizosphere fungal communities were dominated by Sodiomyces at the genus level, and the relative abundance of pathogenic fungi, such as Botryotrichum, Plectosphaerella, Pseudogymnoascus, and Fusarium, declined after compost application. Moreover, the α-diversity indexes of the fungal community under compost application rates of 15% and 25% significantly decreased in comparison to the control treatment. The soil SOC, pH, TP, and TN were the main environmental factors affecting fungal community composition. The leaf photosynthetic traits and metal ion contents showed significantly positive correlations with Sodiomyces and Aspergillus. The fungal trophic mode was dominated by Pathotroph–Saprotroph–Symbiotroph and Saprotroph. Overall, our findings provide an important basis for the future application of microbial-based strategies to improve plant tolerance to saline-alkali stress. Full article

Municipal solid waste (MSW) generation continues to increase exponentially, leading to the need for better disposal methods. Approximately 50% of the MSW is landfilled in the United States (US). Landfilling is known for its negative effects on the environment and human health. The objective of this study was to conduct a life cycle assessment (LCA) of some of the most common waste treatment methods and propose an alternative and environmentally friendly integrated waste management method (IWM). The LCA was conducted using OpenLCA. Replacing landfilling, incineration, and composting with recycling, gasification, and anaerobic digestion (IWM) reduced the global warming potential from 899 kg CO₂ eq to −14.6 kg CO₂ eq. The same trend was observed for acidification (from 0.21 kg SO₂ eq to −1.1 kg SO₂ eq), ecotoxicity (from 2363.8 CTUe to 1.22 CTUe), eutrophication (from 0.5 kg N eq to 0.3 kg N eq), smog formation (from 4.4 kg O₃ eq to 1.85 kg O₃ eq), ozone depletion (from 2.1 × 10⁻⁵ kg CFC-11 eq to 0 kg CFC-11 eq), respiratory effects (from 2.8 × 10⁻³ kg PM2.5 eq to −7.25 × 10⁻³ kg PM2.5 eq), cancer (from 2 × 10⁻⁵ CTUh to 1.2 × 10⁻⁷ CTUh), and non-cancer effects (from 6 × 10⁻⁵ to 1.4 × 10⁻⁵ CTUh). The results show that an integrated waste management approach with recycling, gasification, and anaerobic digestion can dramatically reduce the environmental and health impacts of municipal solid waste disposal. Policy reforms, technical innovation, economic investment, and social engagement are needed to change waste management paradigm. Full article