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Population growth has driven an increased demand for solid construction materials, leading to higher amounts of construction and demolition waste (C&DW). Efficient strategies to manage this waste include reduction, reuse, and recycling. Technosols-soils engineered from recycled waste-can potentially help with environmental challenges. However, there is a critical need to explore the potential of Technosols constructed with C&DW for land reclamation, through the growth of native vegetation. The objective of this study was to investigate this potential by studying two Brazilian native tree species (Guazuma ulmifolia and Piptadenia gonoacantha). Technosols were created using C&DW, with and without organic compost and a liquid biofertilizer. A soil health index (SHI) was applied to evaluate the soil quality regarding physical, chemical, and biological indicators of Technosols compared to a control soil (Ferralsol). The results showed that P. gonoacantha plants presented the same height and total biomass in all treatments, while G. ulmifolia plants exhibited greater height and total biomass when grown in Technosols. The enhanced plant development in the Technosols was primarily associated with higher cation exchangeable capacity and nutrients concentration in plant tissues. Technosols with added compost provided higher fertility and total organic carbon. Additionally, Technosols presented higher SHI (∼0.68) compared to control (∼0.38) for both studied species. Our experiment reveals that construction and demolition waste (C&DW) have significant potential to form healthy Technosols capable of supporting the growth of native Brazilian trees. This approach offers a promising alternative for addressing C&DW disposal challenges while serving as a nature-based solution for land reclamation.

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Introduction and aims: In the context of increasing population and decreasing soil fertility, food security is one of humanity's greatest challenges. Large amounts of waste, such as sewage sludge, are produced annually, with their final disposal causing environmental pollution and hazards to human health. Sludge has high amounts of nitrogen (N), and, when safely recycled by applying it into the soil as composted sewage sludge (CSS), its residual effect may provide gradual N release to crops. A field study was conducted in the Brazilian Cerrado. The aims were to investigate the residual effect of successive applications of CSS as a source of N in the common bean (Phaseolus vulgaris L. cv. BRS Estilo)-palisade grass (Urochloa brizantha (A.Rich.) R.D. Webster)-soybean (Glycine max L.) rotation under no-tillage. Additionally, N cycling was monitored through changes in N metabolism; the efficiency of biological N2 fixation (BNF) and its implications for plant nutrition, development, and productivity, was also assessed. Methods: The experiment consisted of a randomized complete block design comparing four CSS rates (10, 15, 20, and 25 Mg ha-1, wet basis) to a control treatment (without adding mineral or organic fertilizer) over two crop years. Multiple plant and soil analyses (plant development and crop yield, Falker chlorophyll index (FCI), enzymatic, biochemical, 15N natural abundance, was evaluated, root and shoot N accumulation, etc.) were evaluated. Results and discussion: Results showed that CSS: i) maintained adequate N levels for all crops, increasing their productivity; ii) promoted efficient BNF, due to the stability of ureide metabolism in plants and increased protein content; iii) increased the nitrate content and the nitrate reductase activity in soybean; iv) affected urease activity and ammonium content due to changes in the plant's urea metabolism; v) increased N accumulation in the aerial part of palisade grass. Composted sewage sludge can be used as an alternative source to meet crops' N requirements, promoting productivity gains and N cycling through forage and improving N metabolism.

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Composted sewage sludge (CSS) is an organic fertilizer that can be used as a source of micronutrients in agriculture. However, there are few studies with CSS to supply micronutrients for the bean crop. We aimed to evaluate micronutrient concentrations in the soil and their effects on nutrition, extraction, export, and grain yield in response to CSS residual application. The experiment was carried out in the field at Selvíria-MS, Brazil. The common bean cv. BRS Estilo was cultivated in two agricultural years (2017/18 and 2018/19). The experiment was designed in randomized blocks with four replications. Six different treatments were compared: (i) four increasing CSS rates, i.e., CSS5.0 (5.0 t ha-1 of applied CSS, wet basis), CSS7.5, CSS10.0, CSS12.5; (ii) a conventional mineral fertilizer (CF); (iii) a control (CT) without CSS and CF application. The available levels of B, Cu, Fe, Mn, and Zn were evaluated in soil samples collected in the 0-0.2 and 0.2-0.4 m soil surface horizons. The concentration, extraction, and export of micronutrients in the leaf and productivity of common beans were evaluated. The concentration of Cu, Fe, and Mn ranged from medium to high in soil. The available levels of B and Zn in the soil increased with the residual rates of CSS, which were statistically not different from the treatments with CF. The nutritional status of the common bean remained adequate. The common bean showed a higher requirement for micronutrients in the second year. The leaf concentration of B and Zn increased in the CSS7.5 and CSS10.0 treatments. There was a greater extraction of micronutrients in the second year. Productivity was not influenced by the treatments; however, it was higher than the Brazilian national average. Micronutrients exported to grains varied between growing years but were not influenced by treatments. We conclude that CSS can be used as an alternative source of micronutrients for common beans grown in winter.

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The black soldier fly, Hermetia illucens (BSF, Diptera: Stratiomyidae) is an insect with high protein value and a potential feed agent for animals aimed for human consumption. The growth parameters of BSF larvae reared on four substrates-restaurant-waste, fruit-waste, fish-waste, and commercial tilapia food-for 41 days before processing for inclusion into Oreochromis niloticus (Perciformes: Cichlidae, Nile tilapia) commercial fry diets at 30% (70:30) were determined. On fly larvae, the food substrate based on restaurant waste yielded the greatest larval weight and length. BSF larvae fed a fish-waste diet showed the shortest developmental time. The fruit-waste diet induced the lowest weight and length in the fly larvae/pre-pupae (immature stage). The pre-pupal protein values were similar to commercial food. On fry-fish, the diets with pre-pupae grown on fish waste showed the greatest yields regarding weight (biomass), length, and nutritional content. These results suggest the BSF has the potential to be used in fish feed and provides an alternative for commercial cultivation.

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RESUMO A crescente geração de resíduos sólidos urbanos é um problema que atinge países de diversos níveis de desenvolvimento. A falta de adequados planejamento e gerenciamento de resíduos sólidos urbanos acarreta prejuízos à qualidade de vida da população e ao ambiente e elevação dos custos do manejo desses resíduos. O presente trabalho apresenta o panorama dos gastos públicos municipais despendidos entre 2009 e 2017 com os serviços de limpeza urbana de 31 dos 34 municípios que compõem a Região Metropolitana de Belo Horizonte. Os municípios foram ordenados por faixas populacionais, conforme classifica o Instituto Brasileiro de Geografia e Estatística. Realizou-se análise estatística descritiva, e a normalidade dos dados foi testada (teste de Shapiro-Wilk; α = 5%). Também avaliou-se a existência de correlação entre as receitas e as despesas municipais com o manejo de resíduos sólidos urbanos (teste de Spearman; α = 5%). Verificou-se, ainda, a existência de diferenças significativas entre grupos de municípios em função do agrupamento por faixas populacionais (teste de Kruskal-Wallis; α = 5%). Os resultados apontaram diferenças significativas do custo per capita despendido pelos municípios com os serviços de manejo de resíduos sólidos urbanos entre as seis faixas populacionais comparadas. Os gastos municipais relativos à faixa populacional "acima de 500.000 habitantes" foram significativamente superiores aos das demais faixas. Embora não discuta qualidade e cobertura dos serviços, este trabalho contribui para a área, visto a escassez de estudos envolvendo custos e resíduos sólidos urbanos, bem como possibilita a criação de estratégias direcionadas à otimização dos gastos públicos visando à sustentabilidade financeira.

ABSTRACT The growing generation of urban solid waste (USW) undistinctively affects countries having different levels of development. The lack of adequate planning and management of USW causes damage to the quality of life of the population and to the environment and increases the costs of handling this waste. This work is aimed to present a panorama of municipal public expenditures between 2009 and 2017 on urban cleaning services in 31 out of 34 municipalities comprising the Metropolitan Region of Belo Horizonte, Brazil. The municipalities were ordered by population groups, according to the classification of the Brazilian Institute of Geography and Statistics. A descriptive statistical analysis was performed and the normality of the data was tested (Shapiro-Wilk test; α = 5%). The existence of a correlation between municipal revenues and expenses relative to the management of USW was also evaluated (Spearman test; α = 5%). The existence of significant differences among groups of municipalities due to the grouping by population (Kruskal-Wallis test; α = 5%) was also verified. In general, the results showed significant differences in the per capita cost spent by municipalities with SUW management services among the six population groups compared. Municipal expenditures for the "over 500,000 inhabitants" population group were significantly higher than for other groups. Although it does not discuss quality and extension of the services, this work contributes to the area, given the scarcity of studies involving costs and SUW, as well as enables the creation of strategies aimed at optimizing public spending aimed at financial sustainability.

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This work presents a study on the use of wood and plastic wastes generated in abundance in Merida, Mexico, to help to reduce them in order to mitigate environmental deterioration. The use of these wastes is proposed to obtain a low-cost building material. So, the escalation process (i.e., extrusion) at the pilot level to obtain a prototype of a wood-plastic composite (WPC) corrugated sheet to evaluate the technical feasibility to make a low-cost product is reported. A corrugated sheet with recycled high-density polyethylene (R-HDPE) was produced. The R-HDPE was collected from Merida's Separation Plant. The wood came from the trimmings of different varieties of trees and shrubs that are periodically pruned. WPC sheets with virgin HDPE were prepared to assess its effect on the materials' mechanical performance. The wood/HDPE weight ratio was 40/60. The performance of the WPC sheets was compared with that of commercial products with similar characteristics, namely acrylic and polyester sheets reinforced with fibreglass, and black asphalt-saturated cardboard sheets. Thus, the effect of natural weathering on the maximum tensile tearing force and on the maximum flexural load of the different types of sheets was evaluated. Although the mechanical performance of the WPC sheets was lower than that of the acrylic and polyacrylic sheets, their performance was much better than that of the cheap black asphalt-saturated cardboard sheets. So, they are a good option to be used as low-cost temporary roofing.

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Sewage sludge (SS) is widely used in agriculture in several countries around the world. However, the impact of successive applications of SS on soil and the risks of nutrient leaching are often neglected. In this study, corn was grown on a constructed wetland for four crop cycles (two years), in which the wetland was subjected to successive SS applications. The objective of this study was to evaluate how the successive applications of SS affect the availability and leaching of nutrients in the soil profile, after two years of cultivation. Experiments were performed using a randomized block design with repeated measurements in time, that is, soil was sampled in each harvest. Six treatments were tested: four fertilizations based on sewage sludge, resulting from biological and anaerobic treatment, calculated to provide 25 (SS25), 50 (SS50), 75 (SS75), and 100% (SS100), of the N required for corn production (140 kg ha-1); a mineral fertilization (NPK) (140 kg ha-1 N, 70 kg ha-1 of P2O5 and 40 kg ha-1 of K2O) and a control (without fertilization). The results showed that four consecutive applications of SS100 for two years caused significant accumulation of nutrients and organic matter in the superficial layers of the soil. The electrical conductivity and the concentration of NO3- in the soil solution were higher than those permitted by Brazilian legislation. The adoption of domestic SS in Brazilian agriculture can be a viable alternative in the search for an environment-friendly and economically feasible method for SS disposal.

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Urban-waste bio-organic substances (UW-BOS) have been shown to be capable of extending the photo-Fenton reaction to mildly acidic conditions. In this study, the effects of pH (3-7), UW-BOS, H2O2 and iron concentrations on the photo-Fenton process were systematically assessed using a Doehlert experimental design and response surface methodology for two UW-BOS (CVT230 and FORSUD). Solutions of the model antibiotic sulfadiazine (SDZ) were irradiated in a solar simulator equipped with a 550 W Xenon lamp. The results showed that for UW-BOS contents below 30 mg L-1, SDZ removal proceeds at pH 5 with similar rates for both CVT230 and FORSUD, regardless of Fe(III) concentration. For 50 mg L-1 of UW-BOS or higher, CVT230 performs better than FORSUD, even for low Fe(III) content (1-3 mg L-1). In contrast, half-life times of 35-40 min can only be achieved under mildly acidic conditions with FORSUD for iron concentrations higher than 10 mg L-1. The better performance of CVT230 can be associated with its high hydrophilic/hydrophobic ratio, low E2:E3, higher iron content and possibly higher yields of triplet reactive species generation upon solar irradiation. The most appropriate conditions for each UW-BOS studied are discussed for the first time, which are advantageous for possible engineered applications.

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Singlet oxygen (1O2), hydroxyl radicals (•OH), and excited triplet states of organic matter (3OM*) play a key role in the degradation of pollutants in aquatic environments. The formation rates and quantum yields (Φ) of these reactive intermediates (RI) through photosensitized reactions of dissolved organic matter (DOM) have been reported in the literature for decades. Urban biowaste-derived substances (UW-BOS), a form of organic matter derived from vegetative and urban waste, have recently been shown to be efficient sensitizers in the photo-degradation of different contaminants. Nevertheless, no quantitative measurements of photo-oxidant generation by UW-BOS have been reported. In this study, the formation quantum yields of 1O2 and •OH, as well as quantum yield coefficients of TMP degradation (indicative of 3OM* formation), were quantified for two UW-BOS samples, under 254-nm UV radiation or simulated sunlight and compared to a DOM standard from the Suwanee River (SRNOM). Values of Φ for UW-BOS samples ranged from Φ(+1O2) = 8.0 to 8.8 × 10-3, Φ(+•OH) = 4.1 to 4.3 × 10-6, and f TMP = 1.22 to 1.23 × 102 L Einstein-1 under simulated sunlight and from Φ(+1O2) = 1.4 to 2.3 × 10-2, Φ(+•OH) = 1.3 to 3.5 × 10-3, and f TMP = 3.3 to 3.9 × 102 L Einstein-1 under UV. Although UW-BOS are not necessarily better than natural DOM regarding photosensitizing properties, they do sensitize the production of RI and could potentially be used in engineered treatment systems.

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RESUMO O artigo apresenta os principais aspectos de uma avaliação da coleta seletiva do bairro de São Francisco em Niterói (RJ), após 28 anos de operação ininterrupta. Destacam-se os seus principais aspectos positivos, como a contribuição na disseminação da importância da coleta seletiva, agora estabelecida como obrigação legal na Política Nacional de Resíduos Sólidos (PNRS), bem como o da participação da população local ao longo dos anos. O fato de ser este trabalho gerenciado pela associação de moradores, o Centro Comunitário de São Francisco (CCSF), estabelece um sentimento de pertinência do morador com o projeto. Também se evidencia a prática de recuperação de materiais culturais que em outras circunstâncias iriam para o lixo, ou, no caso de uma coleta seletiva tradicional, seriam vendidos como material reciclável. Com a receita da venda de, em média, 20 ton/mês de materiais recicláveis, o projeto não consegue cobrir as despesas com quatro empregados registrados e a manutenção dos equipamentos. Depende de apoio externo para subsistir. Isto contribui para a reflexão sobre a necessidade de se definir as fontes de recursos, conforme estabelece a PNRS, para que a coleta seletiva seja implantada nos municípios.

ABSTRACT This work presents the results of an assessment of source-separation collection of recycling materials in São Francisco neighborhood of Niterói municipality in Rio de Janeiro State, Brazil, after 28 years of uninterrupted operation. Main positives aspects are highlighted: its contribution to the dissemination of recycling activity, presently established as a legal municipality obligation by National Policy of Solid Waste (PNRS); the local population participation all these years; and the pertinence feeling of the residents with the project by the fact of the recycling activity be managed by residents' association, the Community Center of São Francisco (CCSF). Also it is highlighted the recovery of cultural materials whose in the mingled waste collection would be thrown out, or in the traditional source-separated collection would be sold as recycling material. Selling an average of 22 tons of recycling materials per month, São Francisco source-separation collection have not been able to cover the costs of the 4 employees and equipment maintenance. So it depends of financial help to exist and may contribute to the reflection about the funding sources to implement recycling collection in the Brazilian municipalities as established by PNRS.

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A instituição da Política Nacional de Resíduos Sólidos a partir da Lei nº 12.305/2010 e sua regulamentação tiveram como alvo a redução da pressão sobre a utilização de recursos naturais, induzindo à menor geração de resíduos e à disposição final de forma ambientalmente adequada. O Plano Nacional de Resíduos Sólidos indicou metas de redução, reutilização e reciclagem de resíduos sólidos urbanos - rsu’s, entre outras. Desta forma, este trabalho objetivou analisar as bases de dados e informações disponíveis sobre os rsu’s no Brasil, a sua acessibilidade, seus pontos frágeis e possíveis interpretações referentes a três grupos distintos de municípios: os situados na faixa até 50 mil habitantes, entre 50 e 100 mil e acima de 100 mil habitantes, dando ênfase às variáveis que compõem os indicadores de cobertura do serviço de coleta de rsu’s; massa coletada per capita e formas de disposição final...

The institution of the National Solid Waste Policy from the Law No. 12,305/2010 and its regulations have targeted the reduction of pressure on the use of natural resources, leading to less waste generation and disposal in an environmentally appropriate way. The National Solid Waste Policy stated goals of reducing, reusing and recycling of urban solid waste - suw, among others. Thus, this study aimed to analyze the databases and available information on the solid urban waste in Brazil its accessibility and weaknesses. Besides, all the analyses and data interpretation are presented by three groups of municipalities organized by population range: until 50 thousand inhabitants, between 50 and 100 000 and above 100 000 inhabitants, emphasizing variables that are part of solid urban waste main indicators: indicators related to collection service; mass collected per capita and forms of final disposal...

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The objective of this experiment was to evaluated the heavy metal, K and Na in the substrate after the harvest of lettuce, in a experiment with cultivars Brasil 48, Regina 71, Vitória Verde Clara e Grand Rapids and doses of organic compost of municipal waste 0, 17.5, 35 e 52.5 t ha-1, in greenhouse. The variables analised were pH in water, electric conductivit, organic carbon, and avaiable contents of Pb, Cu, Mn, Zn, K and Na in the soil. Results demonstrated that doses of organic compost disturbed the values of pH, organic carbon, electric conductivit, and the avaiable contents of Pb, Cu, Mn, Zn, K and Na in the substrate after the harvest of the four cultivars. Lettuce cultivars influenced the values of organic carbon and the contents of Cu, Mn, Zn K and Na of the same substrate. Increasing the dose of organic compost, values of Pb, Cu, Mn, Zn, K, Na, pH, electric condutivit and organic carbon were increased.

Visando a avaliar os teores de metais pesados, K e Na, no substrato, após a colheita da alface, foi instalado um ensaio com os cultivares Brasil 48, Regina 71, Vitória Verde Clara e Grand Rapids e as doses de composto orgânico de lixo urbano 0, 17,5, 35 e 52,5t ha-1, em casa de vegetação. Foram analisados: pH em água, condutividade elétrica, carbono orgânico e teores disponíveis de Pb, Cu, Mn, Zn, K e Na no solo. Os resultados demonstraram que as doses de composto orgânico de lixo urbano alteraram os valores de carbono orgânico, condutividade elétrica, pH e os teores disponíveis de Pb, Zn, Cu, Mn, K e Na do substrato após o cultivo dos quatro cultivares. Estes influenciaram os valores de carbono orgânico e os teores de Zn, Cu, Mn, K e Na do mesmo substrato. Quanto maior as doses utilizadas de composto de lixo urbano, maior o teor de Cu, Mn, Pb, Zn, K, Na e maiores o carbono orgânico, a condutividade elétrica e o pH do substrato após o cultivo da alface.

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The objective of this experiment was to evaluated the heavy metal, K and Na in the substrate after the harvest of lettuce, in a experiment with cultivars Brasil 48, Regina 71, Vitória Verde Clara e Grand Rapids and doses of organic compost of municipal waste 0, 17.5, 35 e 52.5 t ha-1, in greenhouse. The variables analised were pH in water, electric conductivit, organic carbon, and avaiable contents of Pb, Cu, Mn, Zn, K and Na in the soil. Results demonstrated that doses of organic compost disturbed the values of pH, organic carbon, electric conductivit, and the avaiable contents of Pb, Cu, Mn, Zn, K and Na in the substrate after the harvest of the four cultivars. Lettuce cultivars influenced the values of organic carbon and the contents of Cu, Mn, Zn K and Na of the same substrate. Increasing the dose of organic compost, values of Pb, Cu, Mn, Zn, K, Na, pH, electric condutivit and organic carbon were increased.

Visando a avaliar os teores de metais pesados, K e Na, no substrato, após a colheita da alface, foi instalado um ensaio com os cultivares Brasil 48, Regina 71, Vitória Verde Clara e Grand Rapids e as doses de composto orgânico de lixo urbano 0, 17,5, 35 e 52,5t ha-1, em casa de vegetação. Foram analisados: pH em água, condutividade elétrica, carbono orgânico e teores disponíveis de Pb, Cu, Mn, Zn, K e Na no solo. Os resultados demonstraram que as doses de composto orgânico de lixo urbano alteraram os valores de carbono orgânico, condutividade elétrica, pH e os teores disponíveis de Pb, Zn, Cu, Mn, K e Na do substrato após o cultivo dos quatro cultivares. Estes influenciaram os valores de carbono orgânico e os teores de Zn, Cu, Mn, K e Na do mesmo substrato. Quanto maior as doses utilizadas de composto de lixo urbano, maior o teor de Cu, Mn, Pb, Zn, K, Na e maiores o carbono orgânico, a condutividade elétrica e o pH do substrato após o cultivo da alface.