Compost Research Articles

The Effect of Eco-enzymes and Husk Charcoal on the Growth of Vanilla Seeds

Background: The successful growth and development of the vanilla plant are supported by the availability of soil nutrients that are absorbed by the plant roots. Natural fertilizers derived from plant waste easily decompose in the soil so that they are more quickly absorbed by roots and stored in plant cells. The purpose of this study was to determine the effect of eco-enzymes and husk charcoal on the growth of vanilla seedlings. Methods: This study was designed using a complete randomized block design. The first factor was eco-enzyme (without eco-enzyme and with eco-enzyme 15 ml/plant), namely E0 and E1, the second factor was the husk charcoal dose (0, 5, 10, 15) g/plant, P0, P1, P2, P3. Data were analyzed using ANOVA analysis of variance with Duncan’s multiple range test (DMRT) with a significant difference of 5%. The results showed that the best vanilla growth was obtained by treating it with 15 ml/polybag eco-enzyme and 15 g/polybag coconut shell charcoal (E1P3). Result: The plant height reaches 79.67 cm, the number of leaves reaches 12.67 strands and the width reaches 405.42 mm. The fresh weight of the plants reached 71.33 g, the dry weight of the plants reached 28 g, the fresh weight of the roots reached 8.6 g, and the dry weight of the roots reached 1.27 g. Microscopi observation showed that eco enzymes and coconut shell charcoal infected the roots and filled the tissues, then played a role in increasing the growth of the vanilla seedlings.

Green Manure for Sustainable Crop Production: A Review

Green manuring is an economical and eco-friendly scientific approach to achieve more resilient and sustainable food production for agricultural systems. Incorporation of green manure improves soil condition by increasing soil physical, chemical and biological properties such as organic matter, availability of nitrogen, phosphorus and potassium and also improves soil structure by preventing soil erosion, increasing water holding capacity etc. Green manure acts as a natural fertilizer, releasing nutrients into the soil as it decomposes and increases the nutrient content in the soil and shows positive effect on plant growth and development. Addition of green manure crops contribute to greater fixation of atmospheric nitrogen, and when decomposed, makes the nitrogen availability in the soil, reducing the need for synthetic nitrogen fertilizers in crops. Furthermore, it has a significant impact on several plant growth and yield parameters, resulting in increased agricultural productivity and ecosystem health.

One-third of Southern Ocean productivity is supported by dust deposition.

Natural iron fertilization of the Southern Ocean by windblown dust has been suggested to enhance biological productivity and modulate the climate1-3. Yet, this process has never been quantified across the Southern Ocean and at annual timescales4,5. Here we combined 11 years of nitrate observations from autonomous biogeochemical ocean profiling floats with a Southern Hemisphere dust simulation to empirically derive the relationship between dust-iron deposition and annual net community production (ANCP) in the iron-limited Southern Ocean. Using this relationship, we determined the biological response to dust-iron in the pelagic perennially ice-free Southern Ocean at present and during the last glacial maximum (LGM). We estimate that dust-iron now supports 33% ± 15% of Southern Ocean ANCP. During the LGM, when dust deposition was 5-40-fold higher than today, the contribution of dust to Southern Ocean ANCP was much greater, estimated at 64% ± 13%. We provide quantitative evidence of basin-wide dust-iron fertilization of the Southern Ocean and the potential magnitude of its impact on glacial-interglacial timescales, supporting the idea of the important role of dust in the global carbon cycle and climate6-8.

ORGANIC FARMING: DEVELOPMENT PROSPECTS IN RUSSIA, TAKING INTO ACCOUNT THE INTERNATIONAL MARKET

The production of organic agriculture products has become one of the most growing areas of economic activity, with projected annual growth of 10-12%. At the same time, the demand for organic products significantly exceeds the supply, which is largely due to the lack of land that can be allocated for this production. Russia, which has significant areas of virtually unused land on which mineral fertilizers and pesticides have not been used for a long time, reaching 19.7 million. ha, has a significant potential for development in this direction. At the same time, considering that a significant part of unused territories is located within the zone of risky agriculture, and also has soils with a low level of natural fertility, degraded, arid, waterlogged, etc., the actual amount of land resources that can be involved in organic agriculture is significantly less. For the most complete introduction into circulation of unused agricultural lands, it is necessary to increase the knowledge intensity and manufacturability of organic agriculture, for which research work in the following areas is highly relevant: 1) optimization of the balance of humus and nutrients in soils, 2) breeding and seed production of crops for organic agriculture, 3) development of biological products for disease and pest control, 4) development of optimal farming systems taking into account local soil and climatic conditions, 5) optimization of agricultural landscapes based on increasing the diversity of agricultural land use. Along with the involvement of unused lands in the organic production system, the development of the industry largely depends on the system of training qualified personnel in this area, which should take into account the specifics of the technologies used, which differ significantly from traditional farming systems. To do this, it is necessary to update existing professional standards, which should include generalized labor functions related to the development and implementation of organic farming technologies, as well as knowledge and skills in organizing organic production. On the basis of updated professional standards, universities should form new professional competencies and a corresponding set of academic disciplines. The personnel training system for the industry should include various levels of training: agricultural classes, higher education, additional professional education.

Comparative life cycle assessment and multi-criteria decision analysis of coffee capsules made with conventional and innovative materials

The following study arises from the need to replace aluminum and polypropylene, from fossil and non-renewable sources, with innovative materials to produce coffee capsules. The analysis was carried out using Life Cycle Assessment (LCA) and Multi Criteria Decision Analysis (MCDA). In the comparison were considered different materials: aluminum capsules, polypropylene, biocompostable plastic in an industrial environment (industrial compost) and biocompostable plastic in a domestic environment (home compost). The results indicate that, for current disposal, biocompostable plastic capsules, particularly those suitable for domestic compost, have lower environmental impacts. These results are also confirmed for the 10-year disposal scenario. Polypropylene capsules demonstrate greater environmental sustainability when considering a recovery rate of 100 % of the raw material. The MCDA analysis confirms that, at the moment, bioplastics represent the solution with the least environmental impact. However, this advantage is reduced if the capsules are made of aluminum and polypropylene using exclusively fully recycled raw material. Furthermore, it appears that the recycling of fossil materials is a viable alternative to bioplastics. It should be noted, however, that polypropylene can be recycled up to three times, unlike aluminum which can be recycled an indefinite number of times.

Black soils in the southwest of the Brazilian Pantanal: Organic carbon and secondary carbonates accumulation in Phaeozems–Gleysol-Chernozem

The southwest of the Brazilian Pantanal contains areas formed by calcareous sediments, which give this hydromorphic environment special characteristics in the formation of soils such as Phaeozems, Chernozems and Gleysols. These soils have a dark surface horizon, enriched with organic matter, high natural fertility in the sorption complex and high clay activity. These soils are important because they store large amounts of organic carbon and can be used in carbon sequestration and greenhouse gases studies. However, despite their abundance in the Pantanal region and importance, these soils are few studied. Thus, our study aimed to characterize the morphology, physical, and chemical attributes of black soils in this region, identifying the main mechanisms of organic carbon and secondary carbonate accumulation. Three profiles located in the municipality of Corumbá-MS were studied, namely Phaeozem (profiles P1), Gleysol (profile P2) and Chernozem (profiles P3). In all profiles, high concentrations of Ca2+, Mg2+ and K+ elements were observed, mainly derived from the sediments of the Serra da Bodoquena and the Urucum-Amolar residual plateau, ion transport fluxes and secondary carbonate dissolution. The preservation of these elements and 2:1 clays is closely linked to the rainfall dynamics of the region, alternating between floods and droughts. The high 2:1 clays and exchangeable Ca2+ benefits the stabilization of organic carbon by means of organic–mineral interactions and promote the increase of humin content. In Phaeozem and Chernozem, the highest levels of secondary carbonates were observed at the top of the B horizons of these soils, where the pressure of CO2 is lower. Being a lowland area under the direct influence of flooding, the development of secondary carbonates is limited in the B horizons of the Gleysol, where access to the water table and root activity at depth increases the CO2 pressure and hinders the re-precipitation of carbonates in this soil, precipitating in the capillary bangs and in the upper zone (surface horizons).

Optimal Production and Dispatch of Renewable Natural Gas, Electricity, and Fertilizer in Municipal-Scale Anaerobic Digestion Supply Chains

Optimal Production and Dispatch of Renewable Natural Gas, Electricity, and Fertilizer in Municipal-Scale Anaerobic Digestion Supply Chains

Formulation of Novel Microbial Consortia for Rapid Composting of Biodegradable Municipal Solid Waste: An Approach in the Circular Economy

Urbanization and rapid industrialization have led to the escalation of municipal solid waste generation and accumulation. Composting is widely recognized as a sustainable solution for solid waste management. However, its long-term investment is considered a disadvantage. The present research study discusses the rapid biotransformation of solid waste into valorized compost. Bacteria were isolated from soil, solid waste, and leachate samples from open dump sites. From the 18 different bacterial consortia created using potential isolates, the five most promising consortia were selected based on concurrent different enzyme production. These selected consortia were incorporated into typical compost bins with Municipal Solid Waste (MSW). Daily monitoring of enzymatic activity, pH, conductivity, bulk density, moisture, and temperature, along with other composting parameters, was conducted. The study’s results demonstrated that consortium No. 5, comprising Bacillus haynesii, Bacillus amyloliquefaciens, and Bacillus safensis, exhibited significant (p<0.05) enzyme activity of cellulase, amylase, lipase and proteinase enzymes during composting compared to the control and other treatment setups. Consortium No. 5 also facilitated rapid and successful composting, as evidenced by significant alterations of composting parameters by exhibiting a shorter average composting time, reducing it from 110±10 days to 20±3 days, showcasing the potential applicability of formulated bacterial consortium as a sustainable and greener approach to the global solid waste problem. The novelty of this study lies in the isolation of local bacterial strains from open dump sites soil, MSW, and MSW leachate samples, which were then utilized in the composting organic fraction of MSW, enhancing the potential for effective waste management.

Impact of urban diets on the nutritional physiology of mealworms

Mealworms ( Tenebrio Molitor), the larval stage of yellow mealworm beetles, are a popular feeder insect for birds, amphibians, reptiles, fish, and even human populations throughout the world. As such, the goal of this work was to understand how the diet of mealworms impacts their nutritional quality as variations in quality can impact the animals (and humans) that consume them. We hypothesized that the nutritional quality of mealworms would be altered by dietary intake with urban substrates resulting in reduced nutritional quality. We divided 500 mealworms among each of the following diets designed to model substrates available in urban vs rural, more natural areas: 100% wheat germ (control); 100% Styrofoam; mixture of soil, grasses, and leaves from urban lawns; mixture of soil, grasses and leaves from rural lawns; mixture of wheat germ + carrots; natural organic fertilizer; or natural organic fertilizer with turf builder. The mealworms were maintained at room temperature and the diets were replaced weekly to prevent spoilage and to remove mealworm wastes. Once a week for three weeks, mealworms were sampled and frozen. Data were analyzed by two-way ANOVA with time and substrate as factors. After 3 weeks, mealworms housed in wheat germ + carrots weighed significantly more than all other groups (p<0.05), whereas those housed in styrofoam or urban lawn substrates weighed significantly less at week 3 as compared to week 1 (p<0.01). The urban lawn substrate resulted in greater molting and the highest number of pupae, but also the greatest mortality among the substrates. Moreover, mealworms provided urban lawn weighed less at week 3 as compared to week 1 (p=0.006). Mealworms maintained on wheat germ had significantly greater total protein content (p<0.05) and the greatest increase in protein content from week 0 to week 3 as compared to any other diet (p<0.05). Glucose content, on the other hand, was significantly lower in all groups at week 3 compared to week 0 (p<0.05). Similar trends were seen in total soluble sugars as mealworms housed in styrofoam, urban lawn, rural lawn, natural fertilizer, and fertilizer with turf builder had lower levels of total soluble sugars at week 3 compared to baseline (p<0.03) whereas those fed wheat germ, with or without carrots, had the highest content (vs WG: p≤0.03; vs WGCAR p<0.05). Interestingly, mealworms housed in wheat germ had higher oxidized lipoproteins compared to all other groups (p<0.05) whereas those fed natural fertilizer or wheat germ and carrots had the lowest level of oxidative stress compared to baseline (p<0.05). Together, these variations support our hypothesis that the nutritional quality of mealworms is altered by dietary intake. In general, urban substrates reduced the nutritional content (body mass, protein, and sugar content) of mealworms, which may negatively impact the health and behavior of predators that rely on such prey for food. This study was funded in part by a Jumpstart Grant awarded to RL by the Graduate and Professional Student Association, Arizona State University. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Exploring Household Composting as an Effective Solution for Urban Waste Management

Organic wastes are generated from many sources’ compiles, solid waste, food, kitchens wastes, etc. Disposal of solid waste is stinging and widespread problem in both urban and rural areas in many developed and developing countries. Collection and disposal of solid waste is one of the major problems of urban environment in most countries worldwide today. Improper Solid Waste Management causes many environmental problems. Traditional composting methods have been common practices in many rural/sub urban areas and requires more time for complete degradation. Traditional method requires large sites for disposal, which nowadays is not possible, as limited spaces are available in the cities. So, here comes the need to find new techniques such as Home Composting. The research focuses on understanding the effectiveness of household composting as a waste management technique for household garbage. Household composting is an attractive method in which small bins can be used as an alternative to composting sites to a small scale. This technique helps to decompose the organic matter in lesser time than the traditional methods. Addition of compost accelerators in the bins increases the decomposition rate. Simply by home composting, the quantity of waste can be reduced. Key Words: Solid Waste Management, Composting, Compost Accelerators, Home Composting, Household Garbage

Plastic particles in urban compost and their grain size distribution

Gathering information on plastic particles in composts and the processes they undergo is important in terms of potentially limiting their further entry into the environment, for example, in improving the fertilising properties of soils. Microplastics (MPs) were determined in composts produced from urban greenery. They are present in decreasing order: polyethylene terephthalate, polystyrene, polyethylene, and polypropylene. The determination of polymers and additives used to improve their properties was performed by pyrolysis and gas chromatography with mass spectrometric detection (Py-GC/MS). Additives and microplastics are most concentrated in composts in the 0.315˗0.63 and 0.63˗1.25 mm grain size class, together with the carbon contained in the compost dry matter. Additives form 0.11˗0.13% of MPs in dry matter of compost. The average concentration of microplastics in the particle size class from 0.63 to 1.25 mm is 2434 ± 224 mg/kg; in the total sample of composts, it is 1368 ± 286 mg/kg of P-MPs.For composts with particle size <2.5 mm, a relationship between the C/N ratio and the plastic particle concentration was statistically significant. It documents a similar behaviour of lignocellulose and plastic particles during the degradation processes. A relationship between the concentration of polymer markers and additives in the compost dry matter and their concentrations in the leachate has been demonstrated. The leachability from compost is higher for additives than for chemical compounds originating from the decomposition of the main components of MPs. The suitability of the use of the compost for agricultural purposes was monitored by the germination index (GI) for watercress. The lowest value of the GI was determined in the particle size class from 0.63 to 1.25 mm. The leachability of polymer markers and additives alone cannot explain the low GI value in this grain size class. The GI value is also influenced by the leachability of chemical compounds characterised by the value of dissolved organic carbon (DOC) and water-leachable nitrogen (Nw). A statistically significant dependence between DOC/Nw and the germination index value was found.

The Use of Products from Leonardite to Improve Soil Quality in Condition of Climate Change

Abstract The principle of sustainable fertilisation in modern agriculture, which ensures that the soil is maintained in a fertile state requires the search for alternatives to manure fertilisation for products based on humic substances to increase the organic matter content of soils.The advantage of leonardite over conventional natural and organic fertilisers is mainly due to its high content of organic matter and humic substances (humic and fulvic acids). Leonardite, due to the presence of humic acids in it, can be suitable for soil amendment and yield of barley. In the conducted studies, the yield increase after adding Rosahumus fertilizer to the soil at a rate of 6 kg.ha−1 + NPK (Nitrogen, Phosphorus, Potasssium) was found to be 11% compared to the control (NPK).There were no changes in the Corg. content of the soil as a result of the application of Rosahumus fertilizer with NPK. The fertilizer only slightly modified the fractional composition of humus. In the future, we should expect an increase in the use of leonardite-derived humic substances in fertilizers and soil conditioners to stabilize soil organic matter.

Effects of Organic Amendments and Mineral Fertilizers on Optimizing Nutrient Cycling in Alkaline Soil

Soil microbial biomass carbon (MBC) and nitrogen (MBN) are indicators of microbial size and soil fertility, representing a vital living nutrient reservoir in the soil. This study aimed to evaluate the impact of various organic sources, such as poultry manure (PM), farmyard manure (FYM), compost (CM), and biochar (BC), along with different levels of mineral fertilizers on soil microbial dynamics and nutrient (N, P) mineralization through laboratory incubation experiments. The organic amendments were applied at rates of 0.25%, 0.5%, and 1.0% of soil carbon (w/w), combined with 75%, 50%, and 25% of recommended doses of NPK (120:90 and 60 kg N, P2O5, and K2O ha-1), respectively. Following the application of amendments, the soil underwent a 16-day incubation period to measure CO2 emissions and a 28-day period for N and P mineralization. The rate of CO2 evolution exhibited a significant increase with higher carbon levels but declined over time. Compost showed the highest CO2 evolution at any given time, followed by PM, FYM, and BC, likely due to a higher readily available fraction of carbon. Compost, particularly at the 1% C level in combination with inorganic fertilizer, led to a significant increase in soil microbial biomass C and N. Nitrogen and phosphorous mineralization increased with the duration of the 28-day incubation period. However, the net release of N and P decreased with higher carbon levels, potentially associated with both immobilization and the fact that higher levels received lower (25%) NPK levels. Nevertheless, soils treated with CM and PM maintained higher levels of N and P, associated with their higher fraction of labile nutrients. These findings suggest that the continuous application of organic sources enhances N and P mineralization, soil microbial biomass, and their activity. Therefore, the regular application of carbon sources emerges as a strategic approach to improving the soil health of less fertile alkaline calcareous soils.

MASK FOR MOISTURIZING SKIN AND BODY MADE FROM COLD-PRESSED PASTE OF PEANUTS (Arachis hypogaea L.)

There are food and plant wastes that cause environmental pollution in many countries around the world. Waste materials are one of the most unconscious uses. With the rapid increase in production, consumption and insensitive communities, industrialization and increasing population cause an intense increase in waste. In order to ensure environmental order and balance, waste must be evaluated and reused in recycling facilities. Peanut (Arachis hypogaea L.) is one of the important oilseed plants and is also considered a protein source in many countries. According to current scientific reports it is known that peanuts have many biological activities such as anti-cancer, antioxidant and anti-inflammatory. Peanut pulp can be used as a raw material source in the production of cellulose fiber products and it can be used in food products, agricultural activities, industry and cosmetics. It is especially common in the recycling field to use it as mulch for plant roots, as natural fertilizer and as chipboard in the field of furniture. In our study, cold-pressed peanut pulp was transformed into products and products with high added value with enriched formulations.

HPV infection and ART: the andrologist’s point of view

Human papilloma virus infection is a common sexually transmitted disease. In addition to its tropism for epithelial mucosae and skin, HPV can also infect the male urogenital tract and strongly bind the sperm head, causing a reduction of semen quality, with detrimental effects on both natural and assisted fertility. An association between HPV and assisted reproductive technology (ART) programs has been reported, and HPV infection of semen seems to have a negative influence on the outcome of these procedures. None of the standard procedures commonly used for sperm selection before ART showed efficacy in eliminating HPV from the sperm head. Several strategies have been suggested to improve viral clearance in semen of infertile patients, such as counseling and anti-HPV vaccination. Moreover, these strategies were able to increase the natural fertility of couples with HPV semen infection. Finally, a modified swim-up with the addition of an enzymatic treatment, despite reducing sperm motility, was reported to eliminate the virus from the sperm head. In this manuscript we propose a flow chart for the management of infertile couples with HPV semen infection. KEY WORDS: HPV, HPV semen infection, assisted reproductive techniques, HPV vaccines.

Evaluation of women's aging influence on sperm passage inside the fallopian tube using 3D dynamic mechanical modeling.

The fallopian tubes play an important role in human fertility by facilitating the spermatozoa passage to the oocyte as well as later actively facilitating the fertilized oocyte transportation to the uterus cavity. The fallopian tubes undergo changes involving biological, physical, and morphological processes due to women aging, which may impair fertility. Here, we have modelled fallopian tubes of women at different ages and evaluated the chances of normal and pathological sperm cells reaching the fertilization site, the ampulla. By utilizing a unique combination of simulative tools, we implemented dynamic three-dimensional (3D) detailed geometrical models of many normal and pathological sperm cells swimming together in 3D geometrical models of three fallopian tubes associated with different women's age groups. By tracking the sperm cell swim, we found that for all age groups, the number of normal sperm cells in the ampulla is the largest, compared with the pathological sperm cells. On the other hand, the number of normal sperm cells in the fertilization site decreases due to the morphological and mechanical changes that occur in the fallopian tube with age. Moreover, in older ages, the normal sperm cells swim with lower velocities and for shorter distances inside the ampulla toward the ovary. Thus, the changes that the human fallopian tube undergoes due to women's aging have a significant influence on the human sperm cell motility. Our model of sperm cell motility through the fallopian tube in relation to the woman's age morphological changes provides a new scope for the investigation and treatment of diseases and infertility cases associated with aging, as well as a potential personalized medicine tool for evaluating the chances of a natural fertilization per specific features of a man's sperm and a woman's reproductive system.

The effect of farming techniques on degradation of DDT in historical cotton farms

DDT was used in the mid 20th century for crop and livestock production. After use, DDT and its degradates DDE and DDD (collectively DDX) remain in the environment for decades. A few studies have reported that the rate of degradation of DDT into its metabolites is affected by various farming techniques like tillage, irrigation, and use of fertilizers. However, most of these studies did not evaluate active farms, and none of them focused on the Southeast US or historical cotton farms. Therefore, in this study, we aimed to determine if different farming techniques affect the decomposition of DDT in Walton County, Georgia, where farms historically grew cotton. Five Walton County farms were sampled for soil, and churches were sampled as control sites. The extensive land history of the farms was recorded, and the soil levels of p,p’-DDT, p,p’-DDE, p,p’-DDD, o,p’-DDT, and o,p’-DDE were measured using gas chromatography-tandem mass spectrometry. All farm sites had detectable levels of p,p’-DDT, p,p’-DDE, and p,p’-DDD, while few sites had detectable levels of o,p’-DDT and o,p’-DDE. Tillage was found to speed up p,p’-DDE degradation, but there was no effect on p,p’-DDT degradation. Plowing was associated with an increase in decomposition of p,p’-DDT, but p,p’-DDE and p,p’-DDD were not significantly increased. The largest difference in the degradation of DDT was based on the fertilizer type. Natural fertilizer sped up degradation of p,p’-DDT and p,p’-DDE; synthetic fertilizer increased p,p’-DDE degradation, but not p,p’-DDT degradation.

Studies on Benefits of Organic Food Products in Human Life during Covid-19

Organic food products have gained considerable attention in recent years due to their perceived health and environmental benefits. This comprehensive review examines the scientific evidence surrounding the advantages of consuming organic foods compared to conventionally produced counterparts. Firstly, organic farming practices emphasize the use of natural fertilizers and biological pest control methods, avoiding synthetic pesticides and genetically modified organisms (GMOs). Numerous studies have demonstrated that organic produce tends to have lower pesticide residues, reducing the potential health risks associated with pesticide exposure. Moreover, organic farming promotes soil health and biodiversity by minimizing the use of synthetic chemicals and fostering sustainable agricultural practices. Healthy soils are essential for nutrient-rich crops and contribute to long-term environmental sustainability. Additionally, organic agriculture typically utilizes crop rotation and intercropping techniques, which enhance soil fertility and resilience. Furthermore, organic livestock production adheres to stringent animal welfare standards, including access to outdoor grazing and the prohibition of routine antibiotic use and growth hormones. As a result, organic meat, dairy, and poultry products often contain higher levels of beneficial nutrients such as omega-3 fatty acids and antioxidants. In terms of nutritional quality, several meta-analyses have suggested that organic fruits and vegetables may have slightly higher levels of certain vitamins, minerals, and antioxidants compared to conventionally grown counterparts. While the differences may be modest, the cumulative effects of consuming organic foods over time could contribute to improved overall health outcomes. Beyond individual health benefits, supporting organic agriculture also has positive implications for environmental conservation and sustainable food systems. By minimizing chemical inputs and promoting biodiversity, organic farming helps mitigate soil erosion, water pollution, and greenhouse gas emissions associated with conventional agriculture.

The Identification and Quantification of 21 Antibacterial Substances by LC-MS/MS in Natural and Organic Liquid Fertilizer Samples.

Antibiotics in animal production are widely used around the world for therapeutic and preventive purposes, and in some countries, they still serve as antibiotic growth stimulants. Regardless of the purpose of using antibiotics in livestock, they may be present in animal tissues and organs as well as in body fluids and excretions (feces and urine). Farm animal excrement in unprocessed form (natural fertilizers) or processed form (organic fertilizers) is applied to agricultural fields because it improves soil fertility. Antibiotics present in fertilizers may therefore contaminate the soil, surface, groundwater, and plants, which may pose a threat to the environment, animals, and humans. Therefore, it is important to develop analytical methods that will allow for the control of the presence of antibacterial substances in natural and organic fertilizers. Therefore, in this study, an LC-MS/MS method was developed and validated for the determination of 21 antibacterial substances in natural and organic liquid fertilizers. The developed method was used to analyze 62 samples of natural and organic liquid fertilizers, showing that over 24% of the tested samples were contaminated with antibiotics, mainly from the group of tetracyclines and fluoroquinolones. Studies of post-fermentation sludge from biogas plants have shown that the processes of anaerobic methane fermentation, pH, and temperature changes taking place in bioreactors do not lead to the complete degradation of antibiotics present in the material used for biogas production. For this reason, monitoring studies of natural and organic fertilizers should be undertaken to limit the introduction of antibiotics into the natural environment.

Source apportionment of soil PTE in a northern industrial county using PMF model: Partitioning strategies and uncertainty analysis

Positive matrix factorization (PMF) has commonly been applied for source apportionment of potentially toxic elements (PTE) in agricultural soil, however, spatial heterogeneity of PTE significantly undermines the accuracy and reliability of PMF results. In this study, a representative industrial-agricultural hub in North China (Xuanhua district, Zhangjiakou City) was selected as the research subject, multiple partition processing (PP) strategies and uncertainty analyses were integrated to advance the PMF modeling and associated algorithm mechanisms were comparatively discussed. Specifically, we adopted three methods to split the research area into several subzones according to industrial density (PP-1), population density (PP-2), and the ecological risk index (PP-3) respectively, to rectify the spatial bias phenomenon of PTE concentrations and to achieve a more interpretable result. Our results indicated that the obvious enrichment of Cd, Pb, and Zn was found in the agricultural soil, with Hg and Cd accounted for 83.49% of the overall potential ecological risk. Combining proper PP with PMF can significantly improve the modelling accuracy. Uncertainty analysis showed that interval ratios of tracer species (Cd, Pb, Hg, and Zn) calculated by PP-3 were consistently lower than that of PP-1 and PP-2, indicating that PP-3 coupled PMF can afford the optimal modeling results. It suggested that natural sources, fertilizers and pesticides, atmosphere deposition, mining, and smelting were recognized as the major contributor for the soil PTE contamination. The contribution of anthropogenic activities, specifically fertilizers and pesticides, and atmosphere deposition, increased by 1.64% and 5.91% compared to PMF results. These findings demonstrate that integration of proper partitioning processing into PMF can effectively improve the accuracy of the model even at the case of soil PTE contamination with high heterogeneity, offering support to subsequently implement directional control strategies.