Anaerobic co-digestion was conducted on the solid residues after three-phase separation of kitchen waste (KWS) and waste-activated sludge (WAS), the synergistic effects and process performance were studied during co-digestion at different ratios of KWS to WAS. KWS and WAS mix ratios of 0:1, 1:4, 1:3, 1:2, 1:1, 2:1, 3:1, 4:1 and 1:0 (based on TS). The results showed that a ratio of KWS to WAS of 1:1 got a very high methane recovery with a methane yield of 310.45 ± 30.05 mL/g VSadded. The highest concentration of free ammonia among all reaction systems was only 70.23 ± 5.53 mg/L, which was not enough to produce ammonia inhibition in the anaerobic co-digestion system. However, when the KWS content exceeded 50%, methane inhibition and prolongation of the lag phase were observed due to the accumulation of volatile fatty acids (VFAs), and during the lag phase. Microbial community analysis showed that various bacterial groups involved in acid production and hydrolysis were mainly dominated by phylum Firmicutes, Chloroflexi, Proteobacteria and Bacteroidetes. Hydrogenotrophic methanogen was found to dominate all archaeal communities in the digesters. Co-digestion of KWS with WAS significantly increased the relative abundance of Methanobacterium compared with anaerobic digestion of WAS alone.

This study assessed the effects of the addition of biochar prepared at 700 °C with different dosages on the anaerobic digestion of food waste. The biochar addition at a concentration of 10.0 g/L increased the cumulative methane yield by 128%, and daily methane production was also significantly promoted. The addition of biochar derived from poplar sawdust significantly increased the relative abundance of dominant bacteria for anaerobic digestion by 85.54-2530% and promoted the degradation of refractory organic matter and the transfer of materials between the hydrolysis and acid production stages. Further analysis has demonstrated that Bathyarchaeia and hydrogenotrophic methanogens were enriched by the biochar addition. Meanwhile, the relative abundances of functional genes, including C5-branched dibasic acid metabolism, and pyruvate metabolism, were increased by 11.38-26.27%. The relative abundances of genes related to major amino acid metabolism, including histidine metabolism, lysine biosynthesis, and phenylalanine, tyrosine, and tryptophan biosynthesis, were increased by 11.96-15.71%. Furthermore, the relative abundances of genes involved in major replication and repair were increased by 14.76-22.76%, and the major folding, sorting, degradation, and translation were increased by 14.47-19.95%, respectively. The relative abundances of genes related to major membrane transport and cell motility were increased by 10.02 and 83.09%, respectively.

In the context of China\'s garbage classification policy, on-site aerobic food waste (FW) digestion is crucial for reducing transportation and disposal costs. The efficiency of this process is largely determined by the microbial community structure and its functions. Therefore, this study aimed to analyze the impact of a personalized microbial consortium (MCM) on the efficiency of aerobic FW digestion and to reveal the underlying mechanisms. An MCM, sourced from naturally degrading FW, was selected to enrich degrading bacteria with relatively high hydrolyzing ability. The functionality of the MCM was evaluated by tracing the successions of microbial communities, and comparing the differences in the forms of organic compounds, metabolic functions, and hydrolase activities. X-ray photoelectron spectroscopy demonstrated that the MCM metabolized faster, and produced more acidic metabolites. Metagenomic analysis indicated that FW inoculated with the personalized MCM increased abundance of Bacillaceae producing hydrolysis enzymes and promoted glycolysis metabolic pathways, enhancing energy generation for metabolism, compared to the commercial effective bacterial agent. This paper provides both theoretical and practical evidence for the improvement of biochemical processor of FW with the personalized MCM, which has promising application prospects and economic value.

A key question in anaerobic microbial ecology is how microbial communities develop over different stages of waste decomposition and whether these changes are specific to waste types. We destructively sampled over time 26 replicate bioreactors cultivated on fruit/vegetable waste (FVW) and meat waste (MW) based on pre-defined waste components and composition. To characterize community shifts, we examined 16S rRNA genes from both the leachate and solid fractions of the waste. Waste decomposition occurred faster in FVW than MW, as accumulation of ammonia in MW reactors led to inhibition of methanogenesis. We identified population succession during different stages of waste decomposition and linked specific populations to different waste types. Community analyses revealed underrepresentation of methanogens in the leachate fractions, emphasizing the importance of consistent and representative sampling when characterizing microbial communities in solid waste.

Studies on food waste in Southeast Asia are currently limited, with a notable absence of comparative analyses investigating the volume and composition of food waste in urban and rural areas through direct measurement. This study aimed to analyze the differences in the quantity, composition, and drivers of household food waste between urban and rural areas. Household food waste was assessed through waste compositional analysis for food and diaries for beverages. This cross-sectional study included 215 households in Bogor Regency, Indonesia. Comparisons between the two areas were performed using an independent t-test. The average of household food waste in Bogor Regency was 77 kg/cap/year (edible 37.7%, inedible 62.3%). Household food waste was higher in urban areas (79.4 kg/cap/year) than in rural areas (45.8 kg/cap/year) (p<0.001). Cereals, tubers and their derivatives (especially rice) and vegetables were the major contributors to edible food waste, whereas fruits were the main contributors to inedible food waste in both areas. Food waste drivers were spoilage/staleness/moldiness, changes in texture, short shelf life, cooking too much, and plate leftovers. Households in urban areas had a higher quantity of food waste and disposed of more edible food than those in rural areas. Meanwhile, the drivers of food waste generation were similar in both areas. Understanding the quantity, composition, and drivers of household food waste is pivotal for developing effective awareness campaigns and fostering behavioral changes to prevent household food waste.

Aedes aegypti mosquitos are the primary vector for dengue, chikungunya, and Zika viruses and tend to breed in small containers of water, with a propensity to breed in small piles of trash and abandoned tires. This study piloted the use of aerial imaging to map and classify potential Ae. aegypti breeding sites with a specific focus on trash, including discarded tires. Aerial images of coastal and inland sites in Kenya were obtained using an unmanned aerial vehicle. Aerial images were reviewed for identification of trash and suspected trash mimics, followed by extensive community walk-throughs to identify trash types and mimics by description and ground photography. An expert panel reviewed aerial images and ground photos to develop a classification scheme and evaluate the advantages and disadvantages of aerial imaging versus walk-through trash mapping. A trash classification scheme was created based on trash density, surface area, potential for frequent disturbance, and overall likelihood of being a productive Ae. aegypti breeding site. Aerial imaging offers a novel strategy to characterize, map, and quantify trash at risk of promoting Ae. aegypti proliferation, generating opportunities for further research on trash associations with disease and trash interventions.

UNASSIGNED: Uncertainty exists in the drinking water, sanitation, hygiene, and health conditions due to mosquitoes and flies across India. Therefore, this study aimed to assess the availability of drinking water, sanitation, hygiene, and health in India.
UNASSIGNED: We used secondary analysis data on 95,548 household members from the National Sample Survey, which included 113,822 homes and 555,351 persons across India between June 2017 and 2018.
UNASSIGNED: About 36.4% of household members stated that tube wells or boreholes outside the property at a distance of less than 0.2 km were their main source of drinking water. More than 87% of respondents said that the water they drank was free of impurities, and 55.1% said that it had not been treated. About 45.7% of respondents stated that there were no bathrooms in the dwellings. More than 50% of the time, according to the respondents, garbage was not collected. A flea or mosquito problem was reported by about 97% of households. Around 97% of households reported fevers that were caused by a disease.
UNASSIGNED: In India, poor access to drinking water, sanitary facilities, good hygiene, and healthcare existed. The results will support the next visionary programs to increase living standards in the country.

Inevitably, aerobic biological treatment processes generate emissions of ammonia (NH3) and greenhouse gas (GHGs) emissions, especially nitrous oxide (N2O). The rapid bio-drying process (RBD) for food waste (FW) alleviates issues arising from its substantial growth. However, its emissions of NH3 and N2O remain unknown, and the correlation with nitrogen components in the substrate remains unclear, significantly impeding its widespread adoption. Here, the nitrogen loss and its mechanisms in RBD were investigated, and the results are as follows: The total emission of NH3 and N2O were1.42 and 1.16 mg/kg FW (fresh weight), respectively, achieving a 98 % reduction compared to prior studies. Structural equation modeling demonstrates that acid ammonium nitrogen (AN) decomposition chiefly generates NH3 in compost (p < 0.001). Strong correlation (p < 0.001) exists between amino acid nitrogen (AAN) and AN. In-depth analysis of microbial succession during the process reveals that the enrichment of Brevibacterium, Corynebacterium, Dietzia, Fastidiosipila, Lactobacillus, Mycobacterium, Peptoniphilus, and Truepera, are conducive to reducing the accumulation of AN and AAN in the substrate, minimizing NH3 emissions (p < 0.05). While Pseudomonas, Denitrobacterium, Nitrospira, and Bacillus are identified as key species contributing to N2O emissions during the process. Correlation analysis between physicochemical conditions and microbial succession in the system indicates that the moisture content and NO3- levels during the composting process provide suitable conditions for the growth of bacteria that contribute to NH3 and N2O emissions reduction, these enrichment in RBD process minimizing NH3 and N2O emissions. This study can offer crucial theoretical and data support for the resource utilization process of perishable organic solid waste, mitigating NH3 and GHGs emissions.

Anaerobic co-digestion (AcoD) with kitchen waste (KW) is an alternative utilization strategy for algal bloom waste (AW). However, the kinetic characteristic and metabolic pathway during this process need to be explored further. This study conducted a comprehensive kinetic and metagenomic analysis for AcoD of AW and KW. A maximum co-digestion performance index (CPI) of 1.13 was achieved under the 12% AW addition. Co-digestion improved the total volatile fatty acids generation and the organic matter transformation efficiency. Kinetic analysis showed that the Superimposed model fit optimally (R2Adj = 0.9988-0.9995). The improvement of the kinetic process by co-digestion was mainly reflected in the increase of the methane production from slowly biodegradable components. Co-digestion enriched the cellulolytic bacterium Clostridium and the hydrogenotrophic methanogenic archaea Methanobacterium. Furthermore, for metagenome analysis, the abundance of key genes concerned in cellulose and lipid hydrolysis, pyruvate and methane metabolism were both increased in co-digestion process. This study provided a feasible process for the utilization of AW produced seasonally and a deeper understanding of the AcoD synergistic mechanism from kinetic and metagenomic perspectives.

Plastic pollution is becoming a global problem due to its ubiquitous occurrence and the impacts detected for many species. However, the research about plastics in nests of terrestrial bird species has remained relatively overlooked in comparison to those devoted to marine ecosystems. Here we study the occurrence and patterns of use of anthropogenic material in nests of two passerine birds, the Eurasian magpie (Pica pica) and the European serin (Serinus serinus), breeding in an orange tree cultivation in Mediterranean Spain. Our results show that both species use extensively plastic debris as nest material; almost 71% of the European serin nests and 96% of nests of Eurasian magpies contained plastic debris. Furthermore, by analyzing the plastic debris availability in the agricultural landscape surveyed we confirmed a selection pattern in the two species. Thus, both species preferably select plastic filaments over other plastic debris. The Eurasian magpie does not select plastic based on size or color but the European serin avoid black plastics prefer smaller fragments in comparison to the average size available. Moreover, we suggest the apparent similarity of plastic filaments with the natural materials typically used by these species, as well as how they use the plastic in their nests could influence their selection behavior. More studies focused on terrestrial birds inhabiting human modified habitats could offer a deeper approach to how plastic debris interacts with wildlife in different ways.