Biomonitoramento da poluição do ar: uma chave dicotômica para identificação de espécies de líquens

Biomonitoring has been seen as complementary analysis to physicochemical methods and as a low-cost alternative, mainly for regions lacking air pollution control programs. Despite being the most widely used bioindicator for this type of pollution, lichens are not easily identified and this methodology is restricted to groups of expert researchers. Accordingly, the aim of the present study was to analyze lichen diversity in urban and industrial areas, in order to elaborate a dichotomous key to identify the listed species, based on easily visualized features. Lichens with leaf stalks belonging to family Parmeliaceae and genus Parmotrema were the most abundant, which are known for their resistance to air pollution. The study sites generally presented low lichen diversity, which may also have been influenced by the degree of vegetation around them. This result reinforces the importance of green areas for mitigating air pollution in urban environment. The dichotomous key elaborated for the lichen species found aims to support research, environmental education and management activities, and may expand the use of lichens as air-quality bioindicators.O biomonitoramento tem sido considerado como uma análise complementar aos métodos físicoquímicos e como uma alternativa de baixo custo, principalmente para regiões carentes de programasde controle da poluição do ar. Apesar de ser o bioindicador mais utilizado para esse tipo de poluição,os líquens não são facilmente identificados, ficando essa metodologia restrita a grupos depesquisadores especializados. Nesse sentido, o objetivo do presente estudo foi analisar a diversidadede líquens em áreas urbanas e industriais, a fim de elaborar uma chave dicotômica para identificar asespécies listadas, com características de fácil visualização. Líquens foliosos pertencentes à famíliaParmeliaceae e ao gênero Parmotrema foram os mais abundantes, os quais são conhecidos por suaresistência à poluição atmosférica. Os locais do estudo apresentaram, em geral, baixa diversidade delíquens, a qual pode ter sido influenciada também pela grau de vegetação no entorno dos pontos. Esseresultado reforça a importância de áreas verdes para mitigar a poluição do ar em ambiente urbano. Achave dicotômica elaborada para as espécies de líquens encontradas visa apoiar a pesquisa, atividadesde educação ambiental e de manejo, podendo ampliar o uso de líquens como bioindicadores daqualidade do ar

Eficiência do sistema de lodos ativados de uma indústria de equipamentos elétricos

Liquid effluent generation in industrial plants is associated with production processes and employees. Based on the current legislation, these effluents must be subjected to treatment processes in order to be discharged at acceptable levels in receiving waterbodies. The company evaluated in the current study manufactures household and industrial tools and instruments; thus, the aim of the current study is to assess the activated sludge-based effluent treatment system adopted by it. Microscopic analyses of microfauna and biological floc structure, as well as sludge physicochemical and sedimentability analyses, were carried out. The sludge was classified as Pin-Point. Although Arcella sp. prevalence has given sludge a satisfactory clearance feature, the presence of Aspidisca sp. and Trachelophyllum sp. in it has indicated nitrification process and significantly old sludge, respectively. These features combined to low protozoan diversity and lack of micrometazoa have evidenced that sludge quality can be improved. Moreover, sludge overall presented poor settleability. Finally, improvements in the activated sludge system were suggested based on results observed in the current study.A geração de efluentes líquidos em uma planta industrial está associada aos processos produtivos eaos funcionários. Esses efluentes necessitam passar por um processo de depuração que os adequem aníveis aceitáveis para descarte, em corpos hídricos receptores, exigidos pela legislação vigente. Aempresa avaliada neste estudo é fabricante de ferramentas e instrumentos de uso doméstico eindustrial. Com isso, o trabalho teve como objetivo realizar a avaliação do seu sistema de tratamentode efluentes por lodos ativados. Foram realizadas análises microscópicas da microfauna e da estruturado floco biológico, além de análises físico-químicas e de sedimentabilidade do lodo. O lodo foiclassificado como Pin-Point. Apesar da predominância de Arcella sp. conferir ao lodo uma característicade boa depuração, a presença de Aspidisca sp. e Trachelophyllum sp. indicam respectivamente, aocorrência de nitrificação e elevada idade do lodo. Essas características associadas à baixa diversidadede protozoários e a ausência de micrometazoários indicam que a qualidade do lodo pode sermelhorada. Além disso, de forma geral, o lodo apresentou má sedimentabilidade. Por fim, a partir dosresultados, realizou-se a proposição de melhorias

Impact of urbanization on the water quality of the Uberaba River and tributaries

This paper evaluated the quality of the water in Uberaba River and tributaries. Seven sites were sampled, in a 12-km under the influence of the urban area. The sampling site started upstream the raw-water catchment station, passing through the urban perimeter, upstream and downstream the discharge of the effluent treated by the Sewage Treatment Plant. Benthic macroinvertebrates were collected using a Surber net and, after identification, the indices of BMWP, diversity, equitability and dominance were calculated, besides functional group analysis. In each sampling site, it was analyzed microbiological and physicochemical parameters in order to identify possible domestic and/or industrial pollution sources. A rapid assessment protocol (RAP) was also applied, and land use and occupation aspects were mapped. The water collected in the furthest sampling site from the urban area and with vegetation in the surroundings, presented satisfactory quality, based in BMWP index. However, this quality dropped to very poor as the river water crossed the urban perimeter. The land use and occupation map showed a predominance of agriculture/pasture and urbanization. In addition, the presence of E. coli and the high levels recorded for some metals (principally cooper and cadmium), suggested contamination of the water with domestic and industrial effluents.

DIAGNÓSTICO AMBIENTAL DA MICROBACIA DO MUTUM, NA APA DO RIO UBERABA, MINAS GERAIS

A crise mundial da água não se limita em sua disponibilidade, mas também na qualidade da água superficial, que embora em abundância em certas regiões, não é devidamente preservada. A APA do rio Uberaba foi criada principalmente para manutenção dos recursos hídricos para abastecimento público. Contudo, observa-se mudanças no uso e ocupação do solo, resultado da expansão agropecuária nos últimos anos, aumentando a fragmentação florestal, o que favorece o assoreamento e compromete a disponibilidade de água. Assim, o presente estudo realizou o diagnóstico ambiental da microbacia do Mutum, inserida na APA, por meio de biomonitoramento com macroinvertebrados bentônicos, análises visuais, microbiológicas e físico-químicas. Os valores dos parâmetros físico-químicos não ultrapassaram os limites estabelecidos para rios de classe II, com exceção dos metais: Cd, Cu, Fe e Ni, os quais podem ser oriundos de disposição inadequada de resíduos, lixiviação de agrotóxicos e tipo de rocha. A degradação ambiental foi constatada pela aplicação do Protocolo de Avaliação Rápida de Rios (PAR) e confirmada pela presença de E. coli nas amostras de água e pela avaliação dos macroinvertebrados bentônicos. Os índices biológicos mostraram baixa diversidade de táxons e elevada dominância de quironomídeos, larvas de insetos resistentes a estresses ambientais. O ponto com maior estabilidade das margens e proteção pela vegetação ripária apresentou os melhores índices biológicos. Por se tratar de uma Unidade de Conservação de uso sustentável, constituída por propriedades privadas, a qualidade ambiental deve ser monitorada e incentivada na região para que a APA possa manter os serviços ambientais prestados

Eficiência de biocompostos potenciados com adubo químico e aeração facilitada

The aims were to reduce composting time, to evaluate the application of produced composts and to size two composting yards (conventional and potentiated). Eight compost heaps with 400 kg of food industry or urban organic waste were built: 1) control; 2) facilitated aeration; 3) potentiated with facilitated aeration and chemical fertilizer; and 4) chemical fertilizer. The analyzed parameters were pH, temperature, humidity and C/N ratio. Compost heap reached stabilization at 90 days without chemical fertilizer and at 25 days when potentiated, regardless of the waste origin. Stabilized composts were applied to lettuce crop under natural conditions and compared with commercial compost. Composts with chemical fertilizer were the most effective in enabling lettuce seedling growth. For medium-sized cities, the conventional composting yard requires 6.58 ha, whereas the potentiated composting yard requires 1.69 ha, considering the recorded stabilization time of 90 and 25 days, respectively. The potentiated composting was the most efficient because its shorter stabilization time, did not require manual turning and produced compost with higher nutrient content. Besides that, requires an area 74.32% smaller than the conventional yard, fact that enables using this process to treat industrial and urban solid organic waste.Este estudo objetivou reduzir o tempo de compostagem, avaliar a aplicação dos compostos produzidos e dimensionar dois pátios de compostagem (convencional e potencializado). Oito pilhas de compostagem com 400 kg de resíduos orgânicos da indústria alimentícia ou urbanos foram construídos: 1) controle; 2) aeração facilitada; 3) potencializado com aeração facilitada e fertilizante químico; e 4) fertilizante químico. Os parâmetros analisados foram pH, temperatura, umidade e razão C/N. As pilhas de compostagem estabilizaram em 90 dias sem fertilizante e 25 dias quando potencializada. Compostos estabilizados foram aplicados à cultura da alface em condições naturais e comparados com composto comercial. Os compostos com fertilizantes foram os mais eficazes para o crescimento das mudas de alface. Para cidades de médio porte, o pátio de compostagem convencional requer 6,58 ha, enquanto o pátio de compostagem potencializada requer 1,69 ha, considerando o tempo de estabilização de 90 e 25 dias, respectivamente. A compostagem potencializada foi mais eficiente devido ao seu menor tempo de estabilização, por não exigir torneamento manual e produzir composto com maior teor de nutrientes. Ainda, requer uma área 74,32% menor que o pátio convencional, o que possibilita a utilização desse tratamento para resíduos sólidos orgânicos urbanos e industriais

AMENDMENT OF ORGANIC COMPOST PROPRIETIES THROUGH COMPOSTING-VERMICOMPOSTING INTEGRATION

The aim of the current study is to evaluate the effects of integrating composting-vermicomposting to improve the organic compost as from the physicochemical analyses and by their application on Brachiaria decumbens growth. Experiments carried out in composting unit used 30:1 ratio of nitrogen-rich organic waste (raw vegetables, fruits and cooked food) and carbon (dry grass) in 2 pile configurations (with, or without passive aeration). After 60 days, product was subjected to vermicomposting for 45 days. Composts were analyzed to check their quality (temperature, pH, moisture, organic carbon, nitrogen and phosphorus levels), as well as compared to each other as biofertilizers (10% (w/v)) for B. decumbens growth. Data have suggested that the vermicomposting process improved the compost pile by increasing its nitrogen (1.26% to 1.95%), phosphorus (0.64% to 1.2%) and organic carbon contents (17.1% to 18.9%). B. decumbens growth showed no significant differences between those treatments, which indicates that organic fraction should be increased (>10%) to release their nutrients to plant.  O objetivo desse trabalho foi avaliar os efeitos da integração da vermicompostagem no melhoramento de composto orgânico a partir de análises físico-químicas e da sua aplicação no crescimento de Brachiaria decumbens. Os experimentos foram conduzidos em pátio de compostagem (por 60 dias) utilizando 30:1 de resíduos orgânicos ricos em nitrogênio e carbono em duas configurações de pilhas (sem aeração e com aeração facilitada); seguido de tratamento via vermicompostagem (45 dias). Os compostos foram avaliados quanto à temperatura, umidade, carbono orgânico, nitrogênio e fósforo. Após a vermicompostagem, o vermicomposto e composto das pilhas foram comparados com fertilizante sintético (8N:25P) e controle (solo in natura) quanto ao potencial de fertilização 10% (p/v), a partir do crescimento da B. decumbens (22 dias). Os resultados demonstraram que a vermicompostagem aumentou os teores de nitrogênio (1,26 para 1,95%), fósforo (0,64 para 1,2%) e carbono orgânico (17,1 para 18,9%) das pilhas compostadas. O crescimento da B. decumbens não apresentou diferença significativa entre os tratamentos, o que indica que a concentração dos compostos orgânicos deve ser acrescida (>10%), para assim disponibilizar os nutrientes para a planta

The bioremediation potential of filamentous fungi in soil contaminated with lead

Population increase resulting from industrial activities has worsened soil contamination with toxic metals. Given the complex dynamics of these pollutants and the complexity of soil matrices, one of the biggest challenges faced by the environmental field lies on developing effective technologies to remediate contaminated soils. Thus, bioremediation may be a decontamination alternative based on using microorganisms. The aims of the current study are to isolate and characterize filamentous fungi with bioremediation potential to be used in soils contaminated with lead. A soil sample was incubated in Sabouraud Caf Agar medium in BOD at 28ºC. CFUs were counted after 72h of incubation; the three most prominently grown colonies were isolated in new plates containing the same medium. Fungi were transferred to liquid submerged fermentation medium with 20 ppm of lead after 24 h of incubation; they remained in shaker incubator at 30°C, 120 rpm, for 120h. Next, the MP-AES analysis was performed to evaluate the final lead concentration. Isolated fungi such as Aspergillus, Penicillium and Trichoderma removed, 56.82%, 66.77% and 75.29% lead ions, respectively, in comparison to the control. Results confirmed the bioremediation potential of these fungi and their possible use in areas contaminated with the herein investigated metal

BIOMONITORING OF SURFACE WATER TOXICITY RELATED TO URBAN AND INDUSTRIAL WASTEWATER RELEASE

Water toxicity was biomonitoried by Tradescantia pallida, relating the results to physicochemical and qualitative analysis. Two clusters were formed by hierarchical analysis of micronuclei percentage (MN), dissolved oxygen (DO), electrical conductivity (EC) and turbidity. The first cluster corresponded to a stream that receives urban untreated sewage, where the highest MN (6.1%) corroborated the physicochemical results (1.90 mg.L‑1 DO, 575.0 μS.cm‑1 and 115.6 NTU). The other cluster includes sampling sites with pollutants from agriculture, livestock and industry. Some of them presented high MN even with acceptable values of physicochemical parameters, according to the Brazilian legislation. So for a better quality information on water pollution monitoring it is essential to recognize the variables that affect the biotic components, in a holistic approach of aquatic ecosystem. In this sense the bioassay with T. pallida becomes a useful tool that can be applied in many tropical and subtropical regions, because of its widely distribution

Urban influence on the water quality of the Uberaba River basin: an ecotoxicological assessment

Ecotoxicological tests applied to Tradescantia pallida, Allium cepa and Lactuca sativa were used to assess the quality of the Uberaba River basin under urban area influence. Water samples were collected at eight different points during the dry season. The samples were assessed using the following toxicity indicators: micronuclei percentage in T. pallida pollen grains (TRAD-MN), seed germination, root growth, mitotic index (MI) and micronuclei in A. cepa root-cells, and seed germination and root growth in L. sativa. Water physicochemical parameters such as temperature, dissolved oxygen (DO), pH and electric conductivity were assessed in situ. The three plant species were efficient bio-indicators, since they presented good cost-benefit and fast and easily interpreted results, thus completing the physicochemical parameters. There was strong correlation between seed germination and root growth among the ecotoxicological parameters assessed in L. sativa and A. cepa. The micronuclei percentage in T. pallida and the MI in A. cepa presented strong correlation with water electric conductivity and moderate and negative correlation with DO. Water electric conductivity ranged from 75 to 438 µS.cm-1; and the DO concentrations ranged from 0.5 to 6.9 mg.L-1. The importance of pollution control measures in the Uberaba River basin stands out. From the supply-water capture point, the basin is strongly affected by pollution, mainly in the tributaries that cross the city. It presents a short, or almost absent, riparian forest line, residues on the river banks, and it is impacted by discharges of untreated sewage, among other anthropic actions

Urban influence on the water quality of the Uberaba River basin: an ecotoxicological assessment

<div><p>Abstract Ecotoxicological tests applied to Tradescantia pallida, Allium cepa and Lactuca sativa were used to assess the quality of the Uberaba River basin under urban area influence. Water samples were collected at eight different points during the dry season. The samples were assessed using the following toxicity indicators: micronuclei percentage in T. pallida pollen grains (TRAD-MN), seed germination, root growth, mitotic index (MI) and micronuclei in A. cepa root-cells, and seed germination and root growth in L. sativa. Water physicochemical parameters such as temperature, dissolved oxygen (DO), pH and electric conductivity were assessed in situ. The three plant species were efficient bio-indicators, since they presented good cost-benefit and fast and easily interpreted results, thus completing the physicochemical parameters. There was strong correlation between seed germination and root growth among the ecotoxicological parameters assessed in L. sativa and A. cepa. The micronuclei percentage in T. pallida and the MI in A. cepa presented strong correlation with water electric conductivity and moderate and negative correlation with DO. Water electric conductivity ranged from 75 to 438 µS.cm-1; and the DO concentrations ranged from 0.5 to 6.9 mg.L-1. The importance of pollution control measures in the Uberaba River basin stands out. From the supply-water capture point, the basin is strongly affected by pollution, mainly in the tributaries that cross the city. It presents a short, or almost absent, riparian forest line, residues on the river banks, and it is impacted by discharges of untreated sewage, among other anthropic actions.</p></div