Runfa Liao, H. Wen, Jinsong Wu et al.

IEEE Access • 2019

In this paper, we investigate the security threats in mobile edge computing (MEC) of Internet of things, and propose a deep-learning (DL)-based physical (PHY) layer authentication scheme which exploits channel state information (CSI) to enhance the security of MEC system via detecting spoofing attacks in wireless networks. Moreover, three gradient descent algorithms are adopted to accelerate the training of deep neural networks, which enables smaller computation overheads and lower energy consumptions. In addition, the maximum likelihood function of multi-user authentication method is derived, which explains why cross entropy is chosen as the loss function. The vectorization cost function is also derived. The mini batch scheme and $\ell _{2}$ regularization are adopted to improve training accuracy and avoid over-fitting, respectively. Moreover, the simulation and experimental results show that the DL-based PHY-layer authentication approaches can distinguish multiple legitimate edge nodes from malicious nodes and attacker by CSIs, effectively. Our proposed method supports a better performance compared with the traditional hypothesis test based method.

Ehsan Farmahini Farahani, Mohammad Amin Jalali Kondelaji, M. Mirsalim

IEEE Transactions on Magnetics • 2020

In this article, a novel exterior-rotor multiple teeth enhanced-torque switched reluctance motor (SRM) is proposed, which exploits permanent magnets (PMs) inside the end teeth of the neighboring stator poles. First, the topology of the proposed motor, namely PM-SRM, is introduced and its working principle is illustrated. Then, based on the magnetic equivalent circuit (MEC) of the motor, it is proven that the PMs contribute to increase the air-gap flux density and regulate the stator poles flux density. As a result, the output torque of the motor is increased as well. The electromagnetic analyses of the proposed PM-SRM are performed using 3-D finite-element analysis. To validate the improved performance of the proposed PM-SRM, it is compared with its PMless counterpart and a classical 12/10-pole SRM in terms of the output torque and power, losses, and efficiency. It is shown that the proposed motor outperforms the two compared motors in terms of the output power and torque, and efficiency. Finally, a prototype of the motor is fabricated and tested to evaluate the predicted results. Both simulation and experimental results demonstrate the high torque and power production capability of the proposed PM-SRM.

Yu Xu, Tiankui Zhang, Yuanwei Liu et al.

IEEE Internet of Things Journal • 2022

Mobile-edge computing (MEC) networks are facing limited coverage and harsh wireless transmission environments that severely hinder the computation capacity of the Internet-of-Things (IoT) devices. To overcome these issues, this article proposes a novel MEC framework empowered by an unmanned aerial vehicle (UAV) relay and a reconfigurable intelligence surface (RIS). To fully exploit the potentials in terms of computation enhancement brought by the joint UAV and RIS design, we formulate a max–min computation capacity problem via determining the uplink signal detection, active beamforming of UAV, passive beamforming of RIS, time slot partition, computation bits of UAV, and UAV’s trajectory. We develop a concave–convex procedure (CCCP)-based algorithm in an alternating optimization manner over three subproblems to solve the formulated problem. It finds that the CCCP-based algorithm is conducive to decouple the intractable expressions by converting them into new but tractable second-order cone (SOC) constrains. To evaluate the performance of the proposed CCCP-based algorithm, we later design a direct algorithm by exploiting the implicit convexity of the problem. Simulation results demonstrate that the proposed CCCP-based algorithm derives a comparable performance as the direct algorithm, and achieves about 2.57-Mb max-min computation capacity higher compared with the straight flight case, and 8.08-Mb max–min computation capacity higher compared with the case without RIS, which validate the superiority of the joint UAV and RIS design for computation enhancement.

E. Cebrián-Sastre, A. Chiner-Oms, R. Torres-Pérez et al.

Microbiology Spectrum • 2023

Rifampicin is the most important first-line antibiotic against mycobacterial infections, including tuberculosis, one of the top causes of death worldwide. Acquisition of rifampicin resistance constitutes a major global public health problem that makes the control of the disease challenging.

A. Reshetchenko, V. Iurchenko, N. Kurakova et al.

Municipal economy of cities • 2023

In order to implement the state environmental policy and ensure environmental safety, a number of normative legal acts, laws and state standards have been implemented on the territory of Ukraine. Special attention was paid to the State Targeted Environmental Program for the Management of Radioactive Waste, the main principle of which is the implementation of the protection of the population and the natural environment in order to create safe conditions for the existence of current and future generations and ensure sustainable development. The article highlights the results of research and development works on the development and certification of a set of packaging type IR-2 for the transportation and temporary storage of low- and medium-level solid radioactive waste KTTZ-NS-1-02.00.00, as a key element of environmental protection technologies during handling with radioactive waste. The urgent task of handling radioactive waste, which is caused by the accumulation of a significant amount of sludge in the territories of the oil and gas production complex enterprises and requires temporary storage and transportation, has been solved, as a prerequisite for increasing the efficiency of ensuring the environmental safety of the mentioned objects of formation. The technical characteristics of the packaging kit are described in detail, schematic drawings are provided, and the main parameters and dimensions of the developed packaging kit type IR-2 are provided. The scheme of the main stages of the testing of this packaging set and the certificates obtained as a result of such work, which were carried out jointly with representatives of the State Inspection of Nuclear Regulation, are presented. The developed packaging set significantly exceeds the performance of the packaging set currently used in temporary storage facilities. Keywords: environmental safety, technogenically enhanced radioactive waste, protection technologies, containers, low- and medium-level waste.

Samrat MVV Naga, Rao K Kesava, Bernardo Ruggeri et al.

bioRxiv (Cold Spring Harbor Laboratory) • 2017

Abstract The sea contains various microbes which have an ability to reduce and oxidize substances like iron, sulphur, and nitrate. Most of these processes happen in the seawater, but can also be applied for purification of wastewater. In the present work, a consortium of seawater bacteria has been used for the first time in a microbial fuel cell to reduce nitrate in synthetic water samples and produce electricity by oxidizing organic matter. The concentrations of and were reduced to well below their permissible limits. Moreover, the growth of the bacterial consortium at cathode causes an increased electricity production in the cell because of the increased bacterial activity. The performance of the cell with a bicarbonate buffered solution (BBS) at the cathode was superior to that obtained with the commonly used phosphate buffered solution (PBS). As BBS is the natural buffering agent found in the sea, the use of BBS is eco-friendly. The same seawater bacterial consortium could be used at both the anode and the cathode, confirming their adaptability to different environments. Unfortunately, denitrification was accompanied by the generation of high concentrations of at the anode and the cathode, probably because of the use of N 2 gas for sparging the anolyte. This aspect merits further investigation.

Hong Liu, Peiwen Li

ASME 2013 11th International Conference on Fuel Cell Science, Engineering and Technology • 2013

The dimensions of gas flow channels and walls/ribs of PEM fuel cells are optimized using a convenient mathematical model. Experimental work for several PEM fuel cells with modeling-optimized gas flow channels was conducted, and the tested results validate the modeling work and the optimization. The model considered average mass transfer and species’ concentrations in flow channels, which allows the determination of an average concentration polarization, the humidity in anode and cathode gas channels, and thus the proton conductivity of membranes, as well as the activation polarization. An electrical circuit for the current and ion conduction is applied to analyze the ohmic losses from anode current collector to cathode current collector. The modeling computation required relatively less computational time and thus can be applied to compute a large number of cases with various flow channel designs and operating parameters for optimization analysis. Optimum ratio of the width of flow channels against the walls/ribs was found from the modeling analysis. In the experimental work, PEM fuel cells were fabricated based on the flow channel dimensions optimized from the modeling analysis. Experimental results agreed with the modeling analysis satisfactorily in respect to the comparison of V-I performance between fuel cells with several optimized designs. The model is recommended as a tool for optimization design of gas flow channels for PEM fuel cells. The optimization results are of significance to the improvement of PEM fuel cell designs and performance.

Χρυσοβαλάντου Ζιώγου

• 2013

Τα συστήματα κυψελών καυσίμου (ΚΚ) έχουν προσελκύσει το ενδιαφέρον τόσο της βιομηχανικής όσο και της βασικής έρευνας τα τελευταία χρόνια, καθώς αποτελούν μέρος μιας φιλικής προς το περιβάλλον τεχνολογίας για την παραγωγή ηλεκτρικής ενέργειας. Κατά τη διάρκεια της λειτουργίας των ΚΚ εξελίσσονται διάφορα φαινόμενα και η συμπεριφορά τους επηρεάζεται από ένα πλήθος μεταβλητών που σχετίζονται με την θερμοκρασία, τις μερικές πιέσεις των αερίων, τη χρησιμοποίηση των αντιδρώντων και την υγρασία. Σε αυτά τα πλαίσια η ανάπτυξη κατάλληλων μεθόδων ελέγχου κρίνεται επιτακτική καθώς είναι σημαντικό το σύστημα ΚΚ να καθοδηγείται στην κατάλληλη περιοχή λειτουργίας ώστε να επιτυγχάνεται η βέλτιστη απόδοση και να διασφαλίζεται η εύρυθμη λειτουργία του ενώ ταυτόχρονα να διασφαλίζεται η μακροβιότητα του. Η παρούσα διατριβή έχει διττό αντικείμενο ενασχόλησης. Το πρώτο αφορά στην αντιμετώπιση θεμάτων διαχείρισης ενός ολοκληρωμένου συστήματος ΚΚ μέσω της μοντελοποίησης και της βέλτιστης λειτουργίας του. Ενώ το δεύτερο σχετίζεται με την ανάλυση, διερεύνηση και ανάπτυξη μεθόδων προηγμένης ρύθμισης που βασίζονται σε μαθηματικά μοντέλα χρησιμοποιώντας αλγόριθμους προρρητικού ή προβλεπτικού ελέγχου (model predictive control - MPC). Σε αυτό το πλαίσιο το σύστημα ΚΚ αποτελεί το πεδίο πειραματικής εφαρμογής, επιβεβαίωσης και αποτίμησης των αναλυόμενων και προτεινόμενων μεθόδων. Αρχικά αναπτύσσεται ένα μαθηματικό μη-γραμμικό δυναμικό μοντέλο για συστήματα ΚΚ τύπου πολυμερικής μεμβράνης (Polymer Electrolyte Membrane - ΡΕΜ) το οποίο αποτελείται από ένα σύνολο διαφορικών και αλγεβρικών εξισώσεων (ΔΑΕ) που περιγράφουν τα βασικά ισοζύγια μάζας και ενέργειας καθώς και την ηλεκτροχημική συμπεριφορά του συστήματος. Σε αυτές τις εξισώσεις εμφανίζονται κάποιες εμπειρικές παράμετροι, οι βέλτιστες τιμές των οποίων προσδιορίζονται από μια γενικευμένη συστηματική μεθοδολογία εκτίμησης. Ο στόχος της μεθοδολογίας αυτής είναι να προσδώσει πειραματικά επιβεβαιωμένη εγκυρότητα στο μοντέλο που λαμβάνει υπόψη τις αλληλεπιδράσεις των υποσυστημάτων που επηρεάζουν την ΚΚ. Στη συνέχεια παρατίθεται μια εμπεριστατωμένη ανάλυση μεθόδων προηγμένης ρύθμισης που αποτελούν μια ανερχόμενη στρατηγική καθώς μπορούν να αντιμετωπίσουν ταυτόχρονα μη-γραμμικά συστήματα, πολλαπλά κριτήρια βελτιστοποίησης υπό περιορισμούς και να οδηγήσουν το σύστημα στην επιθυμητή κατάσταση μέσω της βέλτιστης λήψης αποφάσεων. Η μελέτη εστιάζει σε δύο μεθόδους προρρητικού ελέγχου, το μη-γραμμικό MPC (NMPC) και το πολυπαραμετρικό MPC (mpMPC). Η πρώτη βασίζεται στην online επίλυση ενός δυναμικού προβλήματος βελτιστοποίησης μη-γραμμικού προγραμματισμού (Nonlinear Programming - NLP), ενώ η δεύτερη βασίζεται στην offline επίλυση ενός προβλήματος πολυπαραμετρικού τετραγωνικού προγραμματισμού (multi-parametric Quadratic Programming - mpQP). Τέλος προτείνεται μία νέα μέθοδος που συνδυάζει τα πλεονεκτήματα των δύο προηγούμενων (mpMPC, NMPC) τροποποιώντας κατάλληλα τον χώρο αναζήτησης των μεταβλητών μέσω της δυναμικής προσαρμογής του, σε ένα υποσύνολο του εφικτού με βάση την πολυεδρική καταμέρισή του. Η συνέργεια αυτή συμβάλει καταλυτικά στην βελτίωση της απόδοσης του βελτιστοποιητή που χρησιμοποιείται για την online επίλυση ενός NLP προβλήματος καιαποτελεί νευραλγική συνιστώσα του προρρητικού ελέγχου. Ακολουθεί η σχεδίαση και ανάπτυξη ενός ολοκληρωμένου πλαισίου ελέγχου το οποίο ενσωματώνει ένα πλήθος πολυμεταβλητών ελεγκτών που βασίζονται στις μεθόδους προηγμένης ρύθμισης που σχεδιάζονται για το πειραματικό σύστημα ΚΚ. Επιπρόσθετα παρουσιάζεται η αρχιτεκτονική του βιομηχανικού συστήματος εποπτικού ελέγχου και της διεπαφής που επιτρέπει τη διασύνδεση των αλγόριθμων προηγμένης ρύθμισης με το σύστημα αυτοματισμού. Το πακέτο λογισμικού που σχεδιάστηκε και αναπτύχθηκε, αναλαμβάνει τη διασύνδεση και το συγχρονισμό της επικοινωνίας μεταξύ των ελεγκτών τύπου MPC και του εποπτικού συστήματος της μονάδας, καθιστώντας με αυτό τον τρόπο εφικτή τη μετάβαση από την θεωρητική μελέτη στην πρακτική εφαρμογή των στρατηγικών προρρητικού ελέγχου. Η μελέτη της απόκρισης των ελεγκτών και της συμπεριφοράς της μονάδας αναλύεται μέσα από ένα πλήθος πειραμάτων (σε επίπεδο προσομοίωσης και online), που παρουσιάζουν τα χαρακτηριστικά της κάθε μεθόδου σε σχέση με τους επιδιωκόμενους στόχους βέλτιστης λειτουργίας που τίθενται για το σύστημα. Για το σκοπό αυτό η μελέτη καλύπτει ένα μεγάλο εύρος λειτουργικών συνθηκών, την ύπαρξη διαταραχών και την έναρξη της λειτουργίας της μονάδας.

Tuba Artan Onat, Özge Çetin

Environmental Research and Technology • 2020

The pollution is a result of drastically rising fossil fuel usage due to increased global population and industrialization. Today’s world needs to replace fossil fuels with new and renewable energy sources. Microbial Fuel Cells (MFCs) are devices that convert the chemical energy to direct electricity by microbial metabolic activity. Microbial growth was actualized at the anodic chamber of MFC and must be controlled carefully by microbial methods. The main aim of this study is optimizing the growth parameters of microorganisms in two-chambered MFC with optical density, dried and wet weight of microorganisms that were grown at the anode chamber of MFC. Moreover, the Chemical Oxygen Demand (COD) values of medium were determined at fed cycles of MFC. The total volume of MFC was 0.7 L and the connection was made with the salt bridge between anode and cathode compartments. The anode chamber was used for bacterial growth that was taken from Akkaya Dam slime, was fed with molasses medium at 5 days intervals. The OD values were determined with a spectrophotometer at 600 nm, COD values were determined with the standard method and wet-dry weight also determined as a function of the incubation period.

Saleema A. Karim, Hsueh-Fen Chen

The Journal of Rural Health • 2020

PURPOSE The United States has experienced a surge of COVID-19 cases and deaths. Regardless of the overall increase in the prevalence and mortality, there are disagreements about the consequences of exposure and contracting COVID-19, specifically in rural areas. Rural areas have inherent characteristics that increase their vulnerability to contracting COVID-19. The objective of this study was to investigate the differences in death rates from COVID-19 between urban and rural areas in the United States. METHODS This study used county-level data. The data set consisted of confirmed COVID-19 cases and deaths along with county-level demographics. The sample consisted of all counties in the 50 US states and DC. Counties were designated as metropolitan, micropolitan, and rural. A zero-inflated negative binomial regression was used to estimate county-level number of deaths conditional on contracting COVID-19. The study focused on COVID-19-related mortality from February 10, 2020, to June 12, 2020. FINDINGS After controlling for county-level characteristics, the rate of COVID-19 deaths was 70.3% (P < .001) for rural counties and 53.4% (P < .001) for micropolitan counties, both significantly lower than metropolitan counties during the study time period. CONCLUSION Over time, rural geography and social isolation may not provide sustainable protection to rural residents from the pandemic. The slow progression provides rural areas additional time and opportunity to learn from the experiences in urban areas that were most affected. Rural areas need to be proactive and develop prevention strategies and response plans to manage and control the spread of COVID-19.

Lisa Cacari Stone, Mary C. Roary, A. Diana et al.

The Journal of Rural Health • 2021

Abstract Purpose In an era of the COVID‐19 pandemic, improving health outcomes for diverse rural communities requires collective and sustained actions across transdisciplinary researchers, intersectoral partners, multilevel government action, and authentic engagement with those who carry the burden—rural communities. Methods Drawing from an analysis of transcriptions and documents from a national workshop on the “State of Rural Health Disparities: Research Gaps and Recommendations,” this brief report underscores the gaps and priorities for future strategies for tackling persistent rural health inequities. Findings Four overarching recommendations were provided by national thought leaders in rural health: (1) create mechanisms to allow the rural research community time to build sustainable community‐based participatory relationships; (2) support innovative research designs and approaches relevant to rural settings; (3) sustain effective interventions relevant to unique challenges in rural areas; and (4) recognize and identify the diversity within and across rural populations and adapt culturally and language‐appropriate approaches. Conclusion The COVID‐19 public health crisis has exacerbated disparities for rural communities and underscored the need for diverse community‐centered approaches in health research and dedicated funding to rural service agencies and populations.

A. Dhesi

• 2018

Stakeholders and involved parties are crucial in a proper management of forest areas, more so in nature park areas. Urban nature areas and more remote peri-urban areas have objectively the most complex management issues due to the potentially high density of visitors and a diverse range of stakeholders. Such areas can also be valuable nature conservation and biodiversity hotspots, further making stakeholder interactions more complex. In this research, we conduct stakeholder identification for two case study areas – an urban forest nature park and a peri-urban forest nature park, with the aim of developing detailed lists of involved parties, including both public and private entities. We identified three main blocks of stakeholders (regulatory, usage, management), and detailed each group and sub-group for the case study areas. Our main results and conclusions include the identification of minor differences particularly explained by geographical and socio-economic contexts for each of the areas, with the regulatory stakeholder group overlapping the most between the two areas. The potential use of such analysis can improve or develop cooperation between previously unobserved stakeholders, and in research contexts, allow for a greater input from various parties that could have been missed in a more broader analysis of a research area.

Sathya V, Swarnatharani C, Indumathi S J et al.

2025 International Conference on Computing and Communication Technologies (ICCCT) • 2025

The Integrated Multi-Phase Energy Harvesting System for urban sewer networks captures renewable energy through a three-stage process. First, Microbial Fuel Cells (MFCs) generate electricity by utilizing microbial digestion of organic matter in wastewater. Next, hydroelectric turbines harness kinetic energy from wastewater flow, even at low rates. Finally, piezoelectric materials convert mechanical stress from pressure variations into electrical power. IoT-enabled smart sensors monitor flow rates and energy production in real-time, while predictive analytics optimize performance by forecasting high-flow events. A centralized battery system, supported by supercapacitors for rapid discharge, manages energy storage. Innovations like debris-resistant turbines and corrosion-resistant materials address operational challenges. This scalable system enhances urban energy recovery, reduces reliance on external power, and aligns with smart city sustainability goals.

R. Premkumar, L. Vijayaraja, R. Dhanasekar et al.

2022 3rd International Conference on Electronics and Sustainable Communication Systems (ICESC) • 2022

Every year, one-third of the food produced in the world, approximately 1.3 billion tons for human consumption is being wasted. Nowadays, tons and tons of foods have been wasted not only by the domestic kitchens but also by the emerging hotel industries. Many new technologies developed to overcome the energy crisis and environmental pollution, but ended up in creating wastages. To get over this problem, energy obtained from renewable resources is the need of the hour. The proposed model mainly deals with the conversion of decomposed food waste into electricity. Microbial Fuel Cells (MFC) are bioreactors that convert chemical energy present in the organic waste into electrical energy through the catalytic reaction of the microorganism which are internally present in the food waste. The efficiency of the MFC mainly depends on the Biological Oxygen Demand (BOD) and the amount of organic matter. The maximum amount of energy obtained is mainly based on the amount of waste in the bioreactor. The significant advantage of the proposed model is "zero waste", as the remaining sludges can be used for fertilizers.

Rachel Armstrong

Journal of Chinese Architecture and Urbanism • 2023

This paper examines the applications of microbial technologies in regenerative architecture, which enliven the built environment and its territories by establishing a different relationship between waste, energy, human inhabitation, and microbial “life.” The specific platform discussed is centered on the microbial fuel cell (an ecologically “just” platform that provides bioelectrical energy, data, and chemical transformation from human waste streams), which are exemplified by a range of demonstrators that establish transactional systems between humans and microbes. These simultaneously “sustainable” and “smart” demonstrators establish operational principles for the wider deployment and uptake of microbial technologies in an urban context. The city-scale implementations of these regenerative systems have the potential to establish the foundations for “living cities,” which are fundamentally bioremediating, resulting in an overall increase in liveliness of our habitats and living spaces.

Smruti Kanwate, V. Tale

Indian Journal of Applied Microbiology • 2018

: Microbial fuel cell (MFCs) uses bacteria to convert organic waste material or chemical energy into electrical energy. These technologies represent various multi-disciplinary approaches for alternate source of energy. By the use of bacteria MFCs turn the energy stored in chemical bonds into the electric current that can use without the need for combustion. The basic working principle of MFCs is based on tenets microbial physiology which is coupled with electrochemistry. The structural design of MFCs consists of components such as cathode, electrolyte, and anode. Electricigens such as Geobacter species are able to oxidize organic matter to CO ₂ . By the use of MFCs electricity is generated by treating urban waste water. MFCs have various practical applications such as waste water treatment, hydrogen production, bioremediation, environmental biosensors etc.

T. Imai, H. Vo, M. Fukushima et al.

Water • 2022

Localized biogenic corrosion and extrication of annoying odors caused by hydrogen sulfide (H2S) have long been a big problem in the management of urban sewer systems. H2S emission control in sewers via chemically or biologically normal oxidation processes has also been investigated extensively and is costly. The objective of this work was to develop a new technology to mitigate the concentration of H2S in sewer pipes using conductive concrete. Experimental results after 66 days show that the concentration of hydrogen sulfide significantly decreased when conductive concrete was used as a microbial fuel cell. Both ordinary Portland cement and conductive concrete were utilized for the target experiment. Elemental sulfur was observed in the coating sludge of conductive concrete, whereas this trend was not observed for ordinary Portland cement. These observations demonstrate that conductive concrete provides an electron pathway from deposited sludge in the bottom of sewer pipes to oxygen dissolved in surface water electrons generated from hydrogen sulfide oxidation in an anaerobic environment via conductive concrete. Finally, regarding the mechanism responsible for hydrogen sulfide oxidation, chemical oxidation was the dominant process, and biological processes did not play a significant role.

S. Hirose, Yugo Nishio, Trang Nakamoto et al.

Resourceedings • 2023

Various issues, such as population growth, agriculture, and urban expansion, have led to the continuous degradation of water resources. To solve this problem, sustainable water treatment technologies are required. In water treatment, microbial fuel cells (MFCs) have attracted attention because of their low cost and low risk of cross-contamination. However, the performance of the MFC degrades because of microbial adhesion to the cathode. In this research, we proposed using a blend of polytetrafluoroethylene (PTFE) and Japanese Sumi ink to prevent the adhesion of microbial cells to the cathode. The hydrophobic properties of PTFE prevented the adhesion of microbes on the cathode surface. In addition, the Sumi ink improved the electrical conductivity and physical stability of the cathode. It was confirmed that the hydrophobic properties of PTFE and the conductive and physical stability of Sumi ink could be fully exploited by adjusting the composition ratio of PTFE and Sumi ink.

M. R. Arredondo

• 2019

Nitrogen removal from wastewaters is necessary to prevent the pollution of receiving water bodies. At the same time, nitrogen is an essential nutrient for plants, so it is used in the production of fertilizers. Both the conventional removal of nitrogen compounds from wastewater and their production are energy intensive. For this reason, recovering nitrogen directly from wastewater, instead of removing it, can result in reduced energy consumption associated with both its production and removal processes. The use of electrochemical systems (ES) and bioelectrochemical systems (BES) for the recovery of ammonia from wastewaters has been investigated over the past few years. These systems have been proposed as a sustainable alternative to conventional processes because they have the potential to recover energy (in the form of electricity or H2) from wastewaters while recovering ammonia. From all the domestic wastewater streams, urine contains most of the nitrogen (around 80%), and represents only 1% of the volume. Urine can be collected by the use of urine-diverting toilets or waterless urinals, preventing the dilution of the nutrients with high volumes of potable water. In this thesis, we evaluated the use of (bio)electrochemical systems for the recovery of total ammonia nitrogen (TAN) from urine. Our focus was on improving the understanding and performance of the system in terms of TAN recovery. This was needed to get the technology closer to application as, at the start of this research, the proof-of-principle had just been demonstrated, and the highest TAN recoveries were around 30%. The feasibility of BES as a technology for energy-efficient TAN recovery was evaluated in Chapter 2. It was shown that BESs can become economically feasible if, on top of electricity or hydrogen production, the benefits of TAN removal are taken into account. According to our analysis, when TAN removal is taken into account, BESs can still be economic at high internal resistances (200 mΩ.m2), which makes it easier for the application of the system at a bigger scale. The need to develop and test a method to effectively extract ammonia from the catholyte solution was identified as one of the main limiting factors of the system. One of the main conclusions from Chapter 2 was that it was crucial to couple an effective TAN stripping system to the BES to increase TAN recovery. This was addressed in Chapter 3, and followed up in Chapters 4 and 5. Finally, it was determined that to improve TAN recovery in BES, the interactions between the factors affecting the recovery of TAN in BES (such as current density, catholyte pH, TAN concentration, etc.) should be studied in more detail. In Chapter 3, we demonstrated that an ES with an integrated gas-permeable hydrophobic membrane unit can effectively recover TAN from urine. Furthermore, the relationship between current density and TAN loading rate was studied in more detail. It was shown that the relationship between the applied current density and the TAN loading, here called the load ratio, is essential to assess the TAN removal efficiency and energy input of (B)ESs. The load ratio is useful to find the conditions in which a (B)ES for the recovery of TAN can be operated optimally, but it does not take into account other parameters essential to assess the performance of (B)ESs. These limitations are discussed throughout the thesis and in Chapter 6. In Chapter 4, a hydrogen-recycling electrochemical system (HRES) was developed to minimize the energy input of electrochemical systems for the recovery of TAN. In this technology, the hydrogen gas produced at the cathode is reused as the electron donor in the anode, allowing for ammonia recovery at high rates and relatively low energy input. This technology can be applied to recover TAN from wastewaters that do not contain enough organic matter to be treated in a BES. Furthermore, it lowers the risk of chloride oxidation, which typically occurs in electrochemical systems treating wastewaters with high concentrations of chloride, such as urine. Chloride oxidation can result in the formation of harmful compounds such as chlorine gas, chlorination byproducts and adsorbable organic halides (AOX). At a load ratio of 1.2-1.3, the system accomplished TAN removal efficiencies of 73-82% and recoveries of 60-73%. Additional hydrogen needed to be supplied by a supporting electrolyzer, which accounted for 4-9% of the total energy demand of the system. Finally, in Chapter 5, we tested the concept of load ratio in a BES. The load ratio can be manipulated either by changing the current density or the TAN loading rate. In a BES the current density cannot be controlled as easily as in an electrochemical system, because it depends on the oxidation of organic matter by microorganisms. At the same time, manipulating the TAN loading rate would directly affect the organic loading rate, and therefore the current density. We ran the BES coupled to a gas-permeable hydrophobic membrane on synthetic urine and urine. Both influents were fed at different dilutions, flow rates and certain modifications (such as removing TAN from urine prior to feeding it to the cell) in order to obtain a variety of load ratios. We found out that there was a clear increasing trend in TAN removal efficiency with respect to load ratio for both human and synthetic urine. We did not obtain load ratios higher than 0.8, which means that the current was not enough to transport all the TAN across the membrane. This resulted in overall low removal efficiencies (2 to 47%, with 3 exceptions from 52- 61%). In Chapter 6, we discuss what may cause these low current densities. In this last chapter, we also focus on the reasons why (B)ESs have not been applied at larger scales yet, and give future perspectives and recommendations to bring this promising technology closer to application.

Zeynal Topalcengiz, L. Strawn, M. Danyluk

PLOS ONE • 2017

The microbial quality of water that comes into the edible portion of produce is believed to directly relate to the safety of produce, and metrics describing indicator organisms are commonly used to ensure safety. The US FDA Produce Safety Rule (PSR) sets very specific microbiological water quality metrics for agricultural water that contacts the harvestable portion of produce. Validation of these metrics for agricultural water is essential for produce safety. Water samples (500 mL) from six agricultural ponds were collected during the 2012/2013 and 2013/2014 growing seasons (46 and 44 samples respectively, 540 from all ponds). Microbial indicator populations (total coliforms, generic Escherichia coli, and enterococci) were enumerated, environmental variables (temperature, pH, conductivity, redox potential, and turbidity) measured, and pathogen presence evaluated by PCR. Salmonella isolates were serotyped and analyzed by pulsed-field gel electrophoresis. Following rain events, coliforms increased up to 4.2 log MPN/100 mL. Populations of coliforms and enterococci ranged from 2 to 8 and 1 to 5 log MPN/100 mL, respectively. Microbial indicators did not correlate with environmental variables, except pH (P<0.0001). The invA gene (Salmonella) was detected in 26/540 (4.8%) samples, in all ponds and growing seasons, and 14 serotypes detected. Six STEC genes were detected in samples: hly (83.3%), fliC (51.8%), eaeA (17.4%), rfbE (17.4%), stx-I (32.6%), stx-II (9.4%). While all ponds met the PSR requirements, at least one virulence gene from Salmonella (invA-4.8%) or STEC (stx-I-32.6%, stx-II-9.4%) was detected in each pond. Water quality for tested agricultural ponds, below recommended standards, did not guarantee the absence of pathogens. Investigating the relationships among physicochemical attributes, environmental factors, indicator microorganisms, and pathogen presence allows researchers to have a greater understanding of contamination risks from agricultural surface waters in the field.

T. Ahmed, M. Noman, Yetong Qi et al.

Plants • 2023

Microbial compost plays a crucial role in improving soil health, soil fertility, and plant biomass. These biofertilizers, based on microorganisms, offer numerous benefits such as enhanced nutrient acquisition (N, P, and K), production of hydrogen cyanide (HCN), and control of pathogens through induced systematic resistance. Additionally, they promote the production of phytohormones, siderophore, vitamins, protective enzymes, and antibiotics, further contributing to soil sustainability and optimal agricultural productivity. The escalating generation of organic waste from farm operations poses significant threats to the environment and soil fertility. Simultaneously, the excessive utilization of chemical fertilizers to achieve high crop yields results in detrimental impacts on soil structure and fertility. To address these challenges, a sustainable agriculture system that ensures enhanced soil fertility and minimal ecological impact is imperative. Microbial composts, developed by incorporating characterized plant-growth-promoting bacteria or fungal strains into compost derived from agricultural waste, offer a promising solution. These biofertilizers, with selected microbial strains capable of thriving in compost, offer an eco-friendly, cost-effective, and sustainable alternative for agricultural practices. In this review article, we explore the potential of microbial composts as a viable strategy for improving plant growth and environmental safety. By harnessing the benefits of microorganisms in compost, we can pave the way for sustainable agriculture and foster a healthier relationship between soil, plants, and the environment.

Meitong Jiang, M. Delgado‐Baquerizo, M. Yuan et al.

New Phytologist • 2023

Soil microbial inoculants are expected to boost crop productivity under climate change and soil degradation. However, the efficiency of native vs commercialized microbial inoculants in soils with different fertility and impacts on resident microbial communities remain unclear. We investigated the differential plant growth responses to native synthetic microbial community (SynCom) and commercial plant growth-promoting rhizobacteria (PGPR). We quantified the microbial colonization and dynamic of niche structure to emphasize the home-field advantages for native microbial inoculants. A native SynCom of 21 bacterial strains, originating from three typical agricultural soils, conferred a special advantage in promoting maize growth under low-fertility conditions. The root : shoot ratio of fresh weight increased by 78-121% with SynCom but only 23-86% with PGPRs. This phenotype correlated with the potential robust colonization of SynCom and positive interactions with the resident community. Niche breadth analysis revealed that SynCom inoculation induced a neutral disturbance to the niche structure. However, even PGPRs failed to colonize the natural soil, they decreased niche breadth and increased niche overlap by 59.2-62.4%, exacerbating competition. These results suggest that the home-field advantage of native microbes may serve as a basis for engineering crop microbiomes to support food production in widely distributed poor soils.

Cheng Gao, Ling Xu, Liliam Montoya et al.

Nature Communications • 2022

Plant response to drought stress involves fungi and bacteria that live on and in plants and in the rhizosphere, yet the stability of these myco- and micro-biomes remains poorly understood. We investigate the resistance and resilience of fungi and bacteria to drought in an agricultural system using both community composition and microbial associations. Here we show that tests of the fundamental hypotheses that fungi, as compared to bacteria, are (i) more resistant to drought stress but (ii) less resilient when rewetting relieves the stress, found robust support at the level of community composition. Results were more complex using all-correlations and co-occurrence networks. In general, drought disrupts microbial networks based on significant positive correlations among bacteria, among fungi, and between bacteria and fungi. Surprisingly, co-occurrence networks among functional guilds of rhizosphere fungi and leaf bacteria were strengthened by drought, and the same was seen for networks involving arbuscular mycorrhizal fungi in the rhizosphere. We also found support for the stress gradient hypothesis because drought increased the relative frequency of positive correlations. Fungi are expected to be more resistant and less resilient than bacteria to environmental disturbances. Here, the authors report complex responses by microbial co-occurrence networks to drought in an agricultural system, challenging simple predictions of fungal and bacterial drought responses.

Jennifer E. Schmidt, R. Vannette, Alexandria N. Igwe et al.

Applied and Environmental Microbiology • 2019

Agriculture relies, in part, on close linkages between plants and the microorganisms that live in association with plant roots. These rhizosphere bacteria and fungi are distinct from microbial communities found in the rest of the soil and are even more important to plant nutrient uptake and health. Evidence from field studies shows that agricultural management practices such as fertilization and tillage shape microbial communities in bulk soil, but little is known about how these practices affect the rhizosphere. We investigated how agricultural management affects plant-soil-microbe interactions by comparing soil physical and chemical properties, plant nutrients, and rhizosphere microbial communities from paired fields under organic and conventional management. Our results show that human management effects extend even to microorganisms living in close association with plant roots and highlight the importance of these bacteria and fungi to crop nutrition and productivity. ABSTRACT Agricultural management practices affect bulk soil microbial communities and the functions they carry out, but it remains unclear how these effects extend to the rhizosphere in different agroecosystem contexts. Given close linkages between rhizosphere processes and plant nutrition and productivity, understanding how management practices impact this critical zone is of great importance to optimize plant-soil interactions for agricultural sustainability. A comparison of six paired conventional-organic processing tomato farms was conducted to investigate relationships between management, soil physicochemical parameters, and rhizosphere microbial community composition and functions. Organically managed fields were higher in soil total N and NO3-N, total and labile C, plant Ca, S, and Cu, and other essential nutrients, while soil pH was higher in conventionally managed fields. Differential abundance, indicator species, and random forest analyses of rhizosphere communities revealed compositional differences between organic and conventional systems and identified management-specific microbial taxa. Phylogeny-based trait prediction showed that these differences translated into more abundant pathogenesis-related gene functions in conventional systems. Structural equation modeling revealed a greater effect of soil biological communities than physicochemical parameters on plant outcomes. These results highlight the importance of rhizosphere-specific studies, as plant selection likely interacts with management in regulating microbial communities and functions that impact agricultural productivity. IMPORTANCE Agriculture relies, in part, on close linkages between plants and the microorganisms that live in association with plant roots. These rhizosphere bacteria and fungi are distinct from microbial communities found in the rest of the soil and are even more important to plant nutrient uptake and health. Evidence from field studies shows that agricultural management practices such as fertilization and tillage shape microbial communities in bulk soil, but little is known about how these practices affect the rhizosphere. We investigated how agricultural management affects plant-soil-microbe interactions by comparing soil physical and chemical properties, plant nutrients, and rhizosphere microbial communities from paired fields under organic and conventional management. Our results show that human management effects extend even to microorganisms living in close association with plant roots and highlight the importance of these bacteria and fungi to crop nutrition and productivity.

Vanessa L. Brisson, Jennifer E. Schmidt, T. Northen et al.

Scientific Reports • 2019

Maize domestication and breeding have resulted in drastic and well documented changes in aboveground traits, but belowground effects on root system functioning and rhizosphere microbial communities remain poorly understood, despite their critical importance for nutrient and water acquisition. We investigated the rhizosphere microbial community composition and structure of ten Zea mays accessions along an evolutionary transect (two teosinte, three inbred maize lines, and five modern maize hybrids) grown in nutrient depleted soil from a low input agricultural system. Microbial community analysis revealed significant differences in community composition between soil compartments (proximal vs. distal rhizosphere) and between plant genetic groups (teosinte, inbred, and modern hybrid). Only a small portion of the microbial community was differentially selected across plant genetic groups: 3.7% of prokaryotic community members and 4.9% of fungal community members were significantly associated with a specific plant genetic group. Indicator species analysis showed the greatest differentiation between modern hybrids and the other two plant genetic groups. Co-occurrence network analysis revealed that microbial co-occurrence patterns of the inbred maize lines’ rhizosphere were significantly more similar to those of the teosintes than to the modern hybrids. Our results suggest that advances in hybrid development significantly impacted rhizosphere microbial communities and network assembly.

R. Schmidt, Kelly Gravuer, A. V. Bossange et al.

PLOS ONE • 2018

Reducing tillage and growing cover crops, widely recommended practices for boosting soil health, have major impacts on soil communities. Surprisingly little is known about their impacts on soil microbial functional diversity, and especially so in irrigated Mediterranean ecosystems. In long-term experimental plots at the West Side Research and Extension Center in California’s Central Valley, we characterized soil microbial communities in the presence or absence of physical disturbance due to tillage, in the presence or absence of cover crops, and at three depths: 0–5, 5–15 and 15–30 cm. This characterization included qPCR for bacterial and archaeal abundances, DNA sequencing of the 16S rRNA gene, and phylogenetic estimation of two ecologically important microbial traits (rRNA gene copy number and genome size). Total (bacterial + archaeal) diversity was higher in no-till than standard till; diversity increased with depth in no-till but decreased with depth in standard till. Total bacterial numbers were higher in cover cropped plots at all depths, while no-till treatments showed higher numbers in 0–5 cm but lower numbers at lower depths compared to standard tillage. Trait estimates suggested that different farming practices and depths favored distinctly different microbial life strategies. Tillage in the absence of cover crops shifted microbial communities towards fast growing competitors, while no-till shifted them toward slow growing stress tolerators. Across all treatment combinations, increasing depth resulted in a shift towards stress tolerators. Cover crops shifted the communities towards ruderals–organisms with wider metabolic capacities and moderate rates of growth. Overall, our results are consistent with decreasing nutrient availability with soil depth and under no-till treatments, bursts of nutrient availability and niche homogenization under standard tillage, and increases in C supply and variety provided by cover crops. Understanding how agricultural practices shift microbial abundance, diversity and life strategies, such as presented here, can assist with designing farming systems that can support high yields, while enhancing C sequestration and increasing resilience to climate change.

Chao Zhang, Daoji Wu, Huixue Ren

Scientific Reports • 2020

Agricultural wastes, such as wheat bran and swine wastewater, were used for bioremediation of oil-contaminated soil. Two optimised strains that could degrade oil efficiently were selected. The result showed that the best ratio of strain A to strain B was 7:3. Swine wastewater could be a replacement for nitrogen source and process water for bioremediation. Next, the Box-Behnken design was used to optimise the culture medium, and the optimal medium was as follows: microbial dosage of 97 mL/kg, wheat bran of 158 g/kg and swine wastewater of 232 mL/kg. Under the optimal medium, the oil degradation rate reached 68.27 ± 0.71% after 40 d. The urease, catalase, and dehydrogenase activities in oil-contaminated soil all increased, and the microbe quantity increased significantly with manual composting. These investigations might lay a foundation for reducing the pollution of agricultural wastes, exploring a late model for bioremediation of oil-contaminated soil.

Jennifer E. Schmidt, A. Kent, Vanessa L. Brisson et al.

Microbiome • 2019

Rhizosphere microbial communities are key regulators of plant performance, yet few studies have assessed the impact of different management approaches on the rhizosphere microbiomes of major crops. Rhizosphere microbial communities are shaped by interactions between agricultural management and host selection processes, but studies often consider these factors individually rather than in combination. We tested the impacts of management (M) and rhizosphere effects (R) on microbial community structure and co-occurrence networks of maize roots collected from long-term conventionally and organically managed maize-tomato agroecosystems. We also explored the interaction between these factors (M × R) and how it impacts rhizosphere microbial diversity and composition, differential abundance, indicator taxa, co-occurrence network structure, and microbial nitrogen-cycling processes. Host selection processes moderate the influence of agricultural management on rhizosphere microbial communities, although bacteria and fungi respond differently to plant selection and agricultural management. We found that plants recruit management-system-specific taxa and shift N-cycling pathways in the rhizosphere, distinguishing this soil compartment from bulk soil. Rhizosphere microbiomes from conventional and organic systems were more similar in diversity and network structure than communities from their respective bulk soils, and community composition was affected by both M and R effects. In contrast, fungal community composition was affected only by management, and network structure only by plant selection. Quantification of six nitrogen-cycling genes (nifH, amoA [bacterial and archaeal], nirK, nrfA, and nosZ) revealed that only nosZ abundance was affected by management and was higher in the organic system. Plant selection interacts with conventional and organic management practices to shape rhizosphere microbial community composition, co-occurrence patterns, and at least one nitrogen-cycling process. Reframing research priorities to better understand adaptive plant-microbe feedbacks and include roots as a significant moderating influence of management outcomes could help guide plant-oriented strategies to improve productivity and agroecosystem sustainability.

Ziheng Peng, Xun Qian, Yu Liu et al.

Nature Communications • 2024

Agriculture contributes to a decline in local species diversity and to above- and below-ground biotic homogenization. Here, we conduct a continental survey using 1185 soil samples and compare microbial communities from natural ecosystems (forest, grassland, and wetland) with converted agricultural land. We combine our continental survey results with a global meta-analysis of available sequencing data that cover more than 2400 samples across six continents. Our combined results demonstrate that land conversion to agricultural land results in taxonomic and functional homogenization of soil bacteria, mainly driven by the increase in the geographic ranges of taxa in croplands. We find that 20% of phylotypes are decreased and 23% are increased by land conversion, with croplands enriched in Chloroflexi, Gemmatimonadota, Planctomycetota, Myxcoccota and Latescibacterota. Although there is no significant difference in functional composition between natural ecosystems and agricultural land, functional genes involved in nitrogen fixation, phosphorus mineralization and transportation are depleted in cropland. Our results provide a global insight into the consequences of land-use change on soil microbial taxonomic and functional diversity.

Samir K. Banerjee, Florian Walder, L. Büchi et al.

The ISME Journal • 2018

Root-associated microbes play a key role in plant performance and productivity, making them important players in agroecosystems. So far, very few studies have assessed the impact of different farming systems on the root microbiota and it is still unclear whether agricultural intensification influences the structure and complexity of microbial communities. We investigated the impact of conventional, no-till, and organic farming on wheat root fungal communities using PacBio SMRT sequencing on samples collected from 60 farmlands in Switzerland. Organic farming harbored a much more complex fungal network with significantly higher connectivity than conventional and no-till farming systems. The abundance of keystone taxa was the highest under organic farming where agricultural intensification was the lowest. We also found a strong negative association (R2 = 0.366; P < 0.0001) between agricultural intensification and root fungal network connectivity. The occurrence of keystone taxa was best explained by soil phosphorus levels, bulk density, pH, and mycorrhizal colonization. The majority of keystone taxa are known to form arbuscular mycorrhizal associations with plants and belong to the orders Glomerales, Paraglomerales, and Diversisporales. Supporting this, the abundance of mycorrhizal fungi in roots and soils was also significantly higher under organic farming. To our knowledge, this is the first study to report mycorrhizal keystone taxa for agroecosystems, and we demonstrate that agricultural intensification reduces network complexity and the abundance of keystone taxa in the root microbiome.

O. Fasusi, C. Cruz, O. Babalola

Agriculture • 2021

The world’s human population continues to increase, posing a significant challenge in ensuring food security, as soil nutrients and fertility are limited and decreasing with time. Thus, there is a need to increase agricultural productivity to meet the food demands of the growing population. A high level of dependence on chemical fertilizers as a means of increasing food production has damaged the ecological balance and human health and is becoming too expensive for many farmers to afford. The exploitation of beneficial soil microorganisms as a substitute for chemical fertilizers in the production of food is one potential solution to this conundrum. Microorganisms, such as plant growth-promoting rhizobacteria and mycorrhizal fungi, have demonstrated their ability in the formulation of biofertilizers in the agricultural sector, providing plants with nutrients required to enhance their growth, increase yield, manage abiotic and biotic stress, and prevent phytopathogens attack. Recently, beneficial soil microbes have been reported to produce some volatile organic compounds, which are beneficial to plants, and the amendment of these microbes with locally available organic materials and nanoparticles is currently used to formulate biofertilizers to increase plant productivity. This review focuses on the important role performed by beneficial soil microorganisms as a cost-effective, nontoxic, and eco-friendly approach in the management of the rhizosphere to promote plant growth and yield.

Qianying Zhang, Tianfei Zheng, Zhenggang Yang et al.

Frontiers in Microbiology • 2023

The agricultural fermentation processing of cigar tobacco leaves (CTLs), including air-curing and agricultural fermentation, carried out by tobacco farmers has rarely been studied. In this study, we have investigated the microbial community in the CTLs during air-curing and agricultural fermentation by 16S rRNA and ITS gene high-throughput sequencing. The results showed that the richness of microbial communities gradually increased with the development of agricultural fermentation, which means that not all microorganisms in CTLs come from the fields where tobacco grows, but gradually accumulate into CTLs during the fermentation process. Enterobacteriaceae, Chloroplast, and Alternaria were the dominant genera in the air-cured CTLs. Aquabacterium, unclassified Burkholderiaceae, Caulobacter, Brevundimonas, and Aspergillus were the dominant genera in the agriculturally fermented CTLs. Acinetobacter, Methylobacterium, Sampaiozyma, and Plectosphaerella first significantly increased, and then significantly decreased during agricultural processing. The changes in microbial communities are mainly related to their different functions during fermentation. This means that when the fermentation effect of the original microbial community in cigar tobacco leaves is not ideal, we can optimize or design the microbial community based on the fermentation function that the microbial community needs to achieve. These results may help adjust and optimize the agricultural fermentation process of CTLs, and help develop the quality of CTLs and increase the income of tobacco farmers.

Yang Zhou, Ming-Rong Deng, Juan Du et al.

Chinese Journal of Engineering Science • 2022

: Agricultural microbial industry belongs to a biotechnology industry with high value addition. It utilizes agricultural microbial resources and biotechnologies, involves fields such as planting, breeding, and agricultural environment, and is crucial in ensuring food security, improving cultivated land quality, and promoting agricultural emission reduction. In this study, we reviewed the development status of agricultural microbial industry in China from the aspects of microbial fertilizer, microbial feeds, microbial pesticide, and microbial enzyme preparation. Then we summarized the development trends of the agricultural microbial technology and industry. Considering the challenges faced by the industry in terms of germplasm resources, technical research, product development, and industry standards, we proposed several key measures including establishing special projects for scientific research platforms, building data information systems, strengthening innovation in the microbial seed industry, and building systems of laws and regulations. To contribute to the high-quality development of China’s agricultural microbial industry, we suggest that an industrial policy system and related supporting measures should be established, the innovation system for the industry should be improved, and high-tech enterprises participating in international competition should be built.

Mihret Frew, Kiros Abebe

Agricultural Reviews • 2020

Milk and milk products play a vital role in human nutrition all over the world. In addition to being a nutritious food for humans, milk and milk products provide a favorable environment for the growth of spoilage and pathogenic microorganisms. Thus, this paper aims to review the microbial properties of milk and fermented milk products produced in different parts of Ethiopia. Microbial contamination may generally occur from within the udder, exterior to the udder, from the surface of milk handling and storage equipment and the traditional practice. The status of the cleanliness of the milkers could be the primary sources of the initial milk contamination. The reviewed dairy products are Milk, Ergo (naturally fermented milk), Kibe (traditional butter), Arera (defatted sour milk) and Ayib (Ethiopian cottage cheese). The existing microbial quality of dairy products produced in the rural part of Ethiopia was poor and did not meet the acceptable quality requirements. The problem was compounded from limited knowledge of the hygienic production, processing and handling of dairy products coupled with inadequate dairy processing infrastructures. Strict hygienic control measures along the value chain to improve the hygienic conditions of milk starting from production to consumption are necessary to provide safe products to the consumer.

PRANITA JAISWAL, YUDH VIR SINGH, NEHA SHARMA et al.

The Indian Journal of Agricultural Sciences • 2020

A field experiment was conducted to study the comparative influence of microbial preparations ,viz. phosphate solubilizing fungi (Jumpstart 2.0), phosphate solubilizing bacteria (PSB), Arbuscular mycorrhiza fungi and humic acid formulation (Bolt GR), in different combinations on soil microbial population and properties (Alkaline phosphatase, dehydrogenase, FDA hydrolytic activity, soil microbial biomass). Bacteria dominated the microbial population, with initial cfu level of 1.73 × 107 to a maximum of 6.2 × 107 gm-1 soil on 90 days after sowing (DAS) in plot, where PSB was applied @ 500 g/ ha, while plots with Jumpstart 2.0 application (@1.65 ml/ kg seed) recorded higher fungal population (7.4 × 106 cfu/g). Treatments and crop age had significant impact on microbial population and their interaction was also found to be significant. Soil microbial properties also increased significantly with crop aging and reached to a higher level on 90 DAS for all the treatments. Microbial activity was invariably found to be highest in T7 treatment (application of PSF @ 0.83 ml/kg seed with humic acid @ 10 kg/ha), and lowest in control plots irrespective of sampling intervals. Results concluded that application of PSF, PSB, AM Fungi and organic formulations in different combination had favourably influenced the microbial properties of soil.

Tim Dumonceaux

Microorganisms • 2023

Peter Kropotkin (1842–1921) is well known as an anarchist intellectual, an amiable mass of contradictions who loved humanity and was highly regarded in academic and intellectual circles, yet also penned “fiery peans to violence” in Le Révolté, the anarchist journal he established with Elisée Reclus in the 1870s [...]

, Sivakumar K, Babu R et al.

Madras Agricultural Journal • 2021

Field investigations were conducted to assess the effect of conservation agricultural practices on soil biological properties and yield of cotton during the kharif season of 2018 and 2019. The experiments were laid out in a split plot design with four main factors viz., conventional tillage with irrigation schedule of 0.8 IW/CPE ratio (M1), conventional tillage with irrigation schedule of 0.6 IW/CPE ratio (M2), minimum tillage with irrigation schedule of 0.8 IW/CPE ratio (M3) and minimum tillage with irrigation schedule of 0.6 IW/CPE ratio (M4). Sub plot had six treatments of weed and nutrient management viz., crop residue mulch with 100% RDF (S1), crop residue mulch with 75% RDF (S2), pre-emergence application of pendimethalin fb one hand weeding with 100% RDF (S3), pre-emergence application of pendimethalin fb one hand weeding with 75% RDF (S4), mechanical weeding twice with 100% RDF (S5) and mechanical weeding twice with 75% RDF (S6). Total microbial populations viz., bacteria, fungal, and actinobacteria were higher in cotton rhizosphere soil with the minimum tillage of irrigation at 0.8 IW/CPE ratio (M3) in the main plot treatments. Cotton rhizosphere soil with crop residue mulch with 100% RDF (S1) recorded a higher microbial population and it was statistically similar with pre-emergence application of pendimethalin fb one hand weeding with 100% RDF (S3) in the sub plot treatments. Among the treatment combination, minimum tillage with irrigation at 0.8 IW/CPE ratio (M3) and crop residue mulch with 100% RDF (S1) recorded a higher microbial population. Similarly, a higher seed yield of cotton was also recorded with minimum tillage and irrigating the crop at 0.8 IW/CPE ratio and pre-emergence application of pendimethalin fb one hand weeding along with application of 100% RDF (M3S3)

Ali YETGİN

Journal of Agricultural Production • 2023

The world is facing a hidden hunger crisis, where millions of people are suffering from nutritional deficiencies despite having access to food. While much research has focused on the quality and quantity of food, recent studies have shown that soil microbial diversity may also play a crucial role in human nutrition. Soil microbes interact with plants in complex ways, influencing the absorption of nutrients and producing compounds that are essential for human health. However, factors such as intensive agriculture, climate change, and soil pollution can lead to a decline in soil microbial diversity, which may contribute to the rise of hidden hunger. In this paper, we explore the link between soil microbial diversity and nutritional deficiencies, examining the latest research on the topic and discussing potential solutions to this pressing global issue. Our findings suggest that promoting soil health and biodiversity could be a key strategy for addressing hidden hunger and improving global nutrition.

A. S. Wieczorek, S. A. Hetz, S. Kolb

• 2014

Abstract. Chitin is the second most abundant biopolymer in terrestrial ecosystems and is subject to microbial degradation. Chitin can be deacetylated to chitosan or can be hydrolyzed to N,N′-diacetylchitobiose and oligomers of N-acetylglucosamine by aerobic and anaerobic microorganisms. Which pathway of chitin hydrolysis is preferred by soil microbial communities has previously been unknown. Supplementation of chitin stimulated microbial activity under oxic and anoxic conditions in agricultural soil slurries, whereas chitosan had no effect. Thus, the soil microbial community likely was more adapted to chitin as a substrate. In addition, this finding suggested that direct hydrolysis of chitin was preferred to the pathway that starts with deacetylation. Chitin was apparently degraded by aerobic respiration, ammonification, and nitrification to carbon dioxide and nitrate under oxic conditions. When oxygen was absent, fermentation products (acetate, butyrate, propionate, hydrogen, carbon dioxide) and ammonia were detected, suggesting that butyric and propionic acid fermentation were along with ammonification likely responsible for apparent anaerobic chitin degradation. In total, 42 different chiA genotypes were detected of which twenty were novel at an amino acid sequence dissimilarity of &gt;50%. Various chiA genotypes responded to chitin supplementation and affiliated with a novel deep-branching bacterial chiA genotype (anoxic conditions), genotypes of Beta- and Gammaproteobacteria (oxic and anoxic conditions), and Planctomycetes (oxic conditions). Thus, this study provides evidence that detected chitinolytic bacteria were catabolically diverse and occupied different ecological niches with regard to oxygen availability enabling chitin degradation under various redox conditions at the level of the community.

Jon Cotton, Veronica Acosta‐Martínez

Agricultural &amp; Environmental Letters • 2018

Core Ideas Decreased CRP funding is resulting in US grassland being tilled. Intensive tillage of grassland rapidly decreases soil health indicators. One month after tilling grassland surface microbial biomass (0–10 cm) decreased 52%. Soil organic C decreased by 20% in the top 30 cm after one growing season. Alternative grassland conversion methods are needed to sustain soil health. Intensive tillage of grassland has negative long‐term effects on soil health, but little data exist to understand how quickly this decline occurs. We sampled a commercial field in the semiarid Southern Plains of the United States before and after tilling grassland and compared the results to adjacent row crop and perennial grass fields. Within the first month of tillage, we detected losses of 52% of microbial biomass C (505 to 241 mg kg −1 soil), 33% of organic C (11.6 to 7.78 g kg −1 soil), 30% of total N (1.09 to 0.760 g kg −1 soil) and 64 to 70% of β‐glucosidase and phosphodiesterase activities. The rapid decreases in these soil health indicators demonstrate that tillage management decisions are crucial for maintaining soil health if perennial grasses are converted to row cropping.