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1.
J Environ Qual ; 49(3): 582-592, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-33016386

RESUMO

We developed a GIS-based tool that values, in a spatially explicit way, the ecosystem services generated by water quality improvements resulting from adoption of agricultural best management practices (BMPs). The tool is calibrated for watersheds in the Chesapeake Bay drainage and includes the benefits from water quality improvements within targeted watersheds, water quality improvements downstream from targeted watersheds, and reductions in pollutant loadings to Chesapeake Bay. The tool is used to investigate specific BMP scenarios adopted within specific watersheds. The results show that (i) BMP adoption generates large positive net benefits to society, with benefit/cost ratios ranging from 22 to 276; (ii) by selecting cost effective BMPs and placing them in the most appropriate places, the cost of meeting pollutant reduction targets would be reduced by 34-71%; and (iii) net benefits from BMP adoption are higher when they are implemented close to or upstream from population centers.


Assuntos
Ecossistema , Qualidade da Água , Agricultura , Água , Abastecimento de Água
2.
J Environ Manage ; 275: 110239, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33059842

RESUMO

PURPOSE: The water footprint provided a full methodology to operationalise the virtual water concept (the volume of water used along a supply chain to produce products and services). A key theme in the water footprint literature is the efficient allocation of water resources at the global scale given the feasibility of trading water intensive commodities from water rich to water poor areas: this is an economic problem of resource allocation between alternative and competing demands, albeit with a novel international component. Moreover, given that price signals indicating relative scarcity are usually either absent or distorted for water, it is also a problem that can be seen through the lens of environmental (or non-market) valuation. However, to date environmental valuation has not been used to inform the efficient use and allocation of water within and between the different locations encompassed by international supply chains. METHODS: Drawing on an agri-food supply chain framework that we propose in this paper, we begin by conceptualising the economic values that accrue to water consumption (blue and green water) and degradation (grey water) at different points along a supply chain. Based on this conceptualisation, we assess the extent to which it is possible to approximate these economic values by relying on existing secondary data on the shadow value of water in different contexts. The use of secondary data in this way is known as benefit (or value) transfer. To achieve this, 706 unit estimates of the economic value of water are collected, standardised and reviewed encompassing off-stream water applications (agriculture, industry and municipal) and in-stream ecosystem services (waste assimilation, wildlife habitat, recreation, hydrological functions and passive uses). From this, a proposed methodology for valuing virtual water is presented and illustrated using the case study of global durum wheat pasta production. RESULTS: The case study shows the total value of the virtual water used to produce one tonne of durum wheat pasta ($212). More importantly, the case study also highlights how variations in economic value between multiple locations where durum wheat is cultivated (Saskatchewan $0.10 m3, Arizona $0.08 m3 and Baja California $0.24 m3) indicate relative water scarcity and thus impact, as well as the potential for a more efficient allocation of virtual water. CONCLUSIONS: The main conclusion from this research is that when geographical disparities in the economic value of water use within a supply chain are accounted for, what was perhaps considered sustainable in volume terms, might not, in fact, represent the optimal allocation. However, future research opportunities highlight the need for additional data collection on the economic value of water in several contexts. This additional data would help the environmental valuation community to undertake a more comprehensive and robust approach to virtual water valuation. This paper is accompanied by the Data in Brief article entitled "Dataset on the in-stream and off-stream economic value of water."


Assuntos
Abastecimento de Água , Água , Arizona , Ecossistema , México
3.
J Korean Med Sci ; 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32924345

RESUMO

The advent of the global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) necessitates a thorough study of the stability and transmissibility in the environment. We characterized the stability of SARS-CoV-2 in three water matrices: fresh, tap, and seawater. The minimum infective dose of SARS-CoV-2 in Vero cells was confirmed to be 10³ PFU/mL. The stability of SARS-CoV-2 varied according to the water matrix: infective SARS-CoV-2 was undetectable after treatment with fresh water and seawater, but remained detectable for 2 days in tap water, when starting with an initial concentration of 104 PFU/mL. When the starting concentration was increased to 105 PFU/mL, a similar trend was observed. In addition, viral RNA persisted longer than infectious virus in all water matrices. This study was conducted in stagnant water containing a significantly high titer of virus, thus, human-to-human transmission of SARS-CoV-2 through the actual aquatic environment is expected to be rare.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/virologia , Água Potável/virologia , Água Doce/virologia , Pneumonia Viral/virologia , Água do Mar/virologia , Microbiologia da Água , Abastecimento de Água , Animais , Betacoronavirus/fisiologia , Chlorocebus aethiops , Infecções por Coronavirus/transmissão , Pandemias , Pneumonia Viral/transmissão , Células Vero , Carga Viral , Cultura de Vírus , Inativação de Vírus
4.
Environ Res ; 189: 109936, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32980018

RESUMO

COVID-19 is an active pandemic that likely poses an existential threat to humanity. Frequent handwashing, social distancing, and partial or total lockdowns are among the suite of measures prescribed by the World Health Organization (WHO) and being implemented across the world to contain the pandemic. However, existing inequalities in access to certain basic necessities of life (water, sanitation facility, and food storage) create layered vulnerabilities to COVID-19 and can render the preventive measures ineffective or simply counterproductive. We hypothesized that individuals in households without any of the named basic necessities of life are more likely to violate the preventive (especially lockdown) measures and thereby increase the risk of infection or aid the spread of COVID-19. Based on nationally-representative data for 25 sub-Saharan African (SSA) countries, multivariate statistical and geospatial analyses were used to investigate whether, and to what extent, household family structure is associated with in-house access to basic needs which, in turn, could reflect on a higher risk of COVID-19 infection. The results indicate that approximately 46% of the sampled households in these countries (except South Africa) did not have in-house access to any of the three basic needs and about 8% had access to all the three basic needs. Five countries had less than 2% of their households with in-house access to all three basic needs. Ten countries had over 50% of their households with no in-house access to all the three basic needs. There is a social gradient in in-house access between the rich and the poor, urban and rural richest, male- and female-headed households, among others. We conclude that SSA governments would need to infuse innovative gender- and age-sensitive support services (such as water supply, portable sanitation) to augment the preventive measures prescribed by the WHO. Short-, medium- and long-term interventions within and across countries should necessarily address the upstream, midstream and downstream determinants of in-house access and the full spectrum of layers of inequalities including individual, interpersonal, institutional, and population levels.


Assuntos
Infecções por Coronavirus/epidemiologia , Armazenamento de Alimentos , Pneumonia Viral/epidemiologia , Saneamento , Abastecimento de Água , Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Feminino , Humanos , Masculino , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , África do Sul , Água
5.
J UOEH ; 42(3): 237-249, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32879188

RESUMO

Access to water and sanitation remain a challenge in many developing countries, especially in pro-poor urban informal settlements where socioeconomic livelihoods are generally low. The aim of this study was to characterise the water and sanitation facilities in the informal settlements of Kisumu City and to evaluate their effect on community hygiene and health. The study focussed on the five urban informal settlements of Nyalenda A, Nyalenda B, Manyatta A, Manyatta B and Obunga, and the three Peri-urban informal settlements of Kogony, Usoma and Otonglo. Using descriptive techniques, the researcher surveyed 114 water sources and all sanitation facilities within 0-15 m and 15-30 m radii of the water sources. The findings revealed dominance of shallow wells and traditional pit latrines as the primary water sources and sanitation facilities, respectively. Out of the water sources studied, 87.7% (100) were shallow wells (mean depth 1.5 m), 9.6% (11) springs and 2.6% (3) boreholes. Most of these shallow wells (83%) were within the urban informal settlements where uses range from washing and cleaning, cooking, and even drinking (13.5%), despite the majority being unprotected. The analysis of the density of sanitation facilities near the water points showed that 32.3% existed within a 15 m radius of the nearest water sources, in violation of the recommended safe distance of 30 m. With an increased density of toilets near critical water sources and other sanitary practices, public health is highly compromised.


Assuntos
Planejamento em Saúde , Pobreza , Saneamento , Classe Social , Toaletes , Saúde da População Urbana , Abastecimento de Água , Humanos , Quênia
6.
Wei Sheng Yan Jiu ; 49(4): 540-545, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-32928345

RESUMO

OBJECTIVE: To understand the rural sanitary conditions in different geographical areas of Shaanxi Province. METHODS: According to the stratified random sampling method, 30 agriculture-related counties were selected(The central area includes 13 counties in Xi'an, Tongchuan, Weinan, Xianyang and Baoji cities. The southern area includes 10 counties in Hanzhong, Ankang, Shangluo cities. The northern area includes 7 counties in Yulin, Yan'an cities. ). Five townships were selected randomly in each county(excluding Chengguan Town), and 4 administrative villages were selected randomly in each township as survey villages, which were collected the soil samples for testing lead, cadmium and chromium in each subject village, and 5 households were randomly selected in each villages as survey households. The data was obtained through data reading, interviews, on-site observations, and laboratory testing, etc. The detection of soil lead and cadmium was carried out according to the Measurement of Soil Quality Lead and Cadmium by Graphite Furnace Atomic Absorption Spectrophotometry(GB/T 17141-1997), and the detection of chromium was carried out according to the Determination of Total Chromium in Soil by Flame Atomic Absorption Spectrometry(HJ 491). The data was statistically analyzed and evaluated according to the central, southern and northern regions. RESULTS: The population coverage of rural centralized water supply in the three regions(central、southern and northern area) was 92. 86%, 75. 49% and 70. 41%, respectively. The penetration rate of sanitary toilets was 28. 18%, 45. 38% and 9. 90%, respectively. The proportion of villages where domestic garbage was randomly stacked was 0. 38%, 4. 00% and 32. 86%, respectively. The proportion of villages where domestic sewage was randomly discharged was 30. 38%, 40. 00% and 60. 00%, respectively. The heavy metals exceeding the standard in the soil were mainly cadmium. The over-standard rates were 4. 62%, 21. 50% and 0. 71%, respectively. The three regional differences of the above result were statistically significant(χ~2=57 676. 74, 18 143. 94, 124. 86, 33. 15 and 54. 12, P<0. 01). CONCLUSION: There was still some decentralized water supply population in the province. The coverage rate of the centralized water supply population and the proportion of drinking water after complete treatment projects were both higher in the central area than in the southern area and northern area. Sanitation toilets have a low penetration rate in the province, which was higher in the southern area than in the central area and the northern area. The domestic garbage was randomly discarded, and domestic sewage was randomly discharged, which was more in the northern area than in the central area and the southern area. Soil cadmium pollution was relatively heavy, mainly in the southern area.


Assuntos
Água Potável , Metais Pesados , Cidades , Humanos , Saneamento , Abastecimento de Água
7.
BMC Public Health ; 20(1): 1385, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32912177

RESUMO

BACKGROUND: In El Salvador, Aedes aegypti mosquitoes transmitting Zika and other arboviruses use water storage containers as important oviposition sites. Promotion of water storage container cleaning is a key element of prevention programs. We explored community perceptions surrounding cleaning practices among pregnant women, male partners of pregnant women, and women likely to become pregnant. METHODS: Researchers conducted 11 focus groups and 12 in-depth interviews which included individual elicitations of Zika prevention measures practiced in the community. Focus group participants rated 18 images depicting Zika-related behaviors according to effectiveness and feasibility in the community context, discussed influencing determinants, voted on community intentions to perform prevention behaviors, and performed washbasin cleaning simulations. In-depth interviews with male partners of pregnant women used projective techniques with images to explore their perceptions on a subset of Zika prevention behaviors. RESULTS: General cleaning of the home, to ensure a healthy environment, was a strong community norm. In this context, participants gave water storage container cleaning a high rating, for both its effectiveness and feasibility. Participants were convinced that they cleaned their water storage containers effectively against Zika, but their actual skills were inadequate to destroy Aedes aegypti eggs. A further constraint was the schedule of water availability. Even during pregnancy, male partners rarely cleaned water storage containers because water became available in homes when they were at work. Furthermore, prevailing gender norms did not foster male participation in domestic cleaning activities. Despite these factors, many men were willing to provide substantial support with cleaning when their partners were pregnant, in order to protect their family. CONCLUSIONS: Behavior change programs for the prevention of Zika and other arboviruses need to improve community members' mosquito egg destruction skills rather than perpetuate the promotion of non-specific cleaning in and around the home as effective. Egg elimination must be clearly identified as the objective of water storage container maintenance and programs should highlight the effective techniques to achieve this goal. In addition, programs must build the skills of family members who support pregnant women to maintain the frequency of effective egg destruction in all water storage containers of the home.


Assuntos
Aedes/virologia , Conhecimentos, Atitudes e Prática em Saúde , Controle de Mosquitos/métodos , Abastecimento de Água , Água , Infecção por Zika virus/prevenção & controle , Zika virus , Adolescente , Adulto , Animais , El Salvador , Feminino , Grupos Focais , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Pesquisa Qualitativa , Características de Residência , Adulto Jovem , Zika virus/crescimento & desenvolvimento , Infecção por Zika virus/transmissão , Infecção por Zika virus/virologia
8.
Environ Monit Assess ; 192(10): 631, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32902699

RESUMO

In recent years, it has been difficult to establish a supply-demand balance between urban growth, increasing population, and existing water resources in many countries. In this study, the Bodrum Peninsula, which is an important tourism center for Turkey, was examined in terms of the relationship between the urban growth of the peninsula, population projections, the need for drinking and potable water, and the availability of the existing water resources. Using the Geographic Information System, it has been determined that the urban growth of the peninsula increased by 11.36% between 1985 and 2010. Urban growth is mostly concentrated in the coastal areas where 2 houses are densely built. The population is expected to increase approximately six times between 2010 and 2060. The amount of drinking and potable water required according to the population projection is 12.38, 26.50, 69.12, and 109.50 hm3/year for 2010, 2030, 2050, and 2060 respectively. The existing water resources of the peninsula will be able to meet the requirements until 2030. In order to meet the water needs of the peninsula until 2055, the Bozalan and Gökçeler dams located nearby as well as the Namnam dam located at mid-range to the peninsular should be built. It is not possible to meet the water needs of the peninsula in 2060 with just the near and medium distance water resources. However, by supplying water from the Akköprü dam located at a further distance, it is possible that 2060 water needs can be met.


Assuntos
Crescimento Demográfico , Recursos Hídricos , Conservação dos Recursos Naturais , Monitoramento Ambiental , Turquia , População Urbana , Abastecimento de Água
9.
Water Sci Technol ; 82(1): 81-96, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32910794

RESUMO

Allocating effluent of wastewater treatment plants to users of economic sectors and satisfying their requirements has created a challenging debate and a need for prioritization. This study assesses the importance of sectors that utilize treated wastewater (TWW) using risk and social acceptability indexes based on expert-oriented approaches. Considered sectors are agriculture, industry, urban green space and natural resources and the study area is located in Iran, around the Isfahan North Wastewater Treatment Plant. The risk index is calculated using Frank and Morgan model and consequently TWW use in the industrial sector is less dangerous than other sectors. Moreover, the social acceptability index, which was determined using Mamdani fuzzy inference set, indicates higher acceptability of TWW use in natural resources sector compared with other sectors. By constructing the conceptual model, generating the decision matrix and using the results of gray relational analysis decision-making model for the four sectors, the allocation priorities of TWW became industry, natural resource, green space, and agriculture respectively. It is suggested that Water and Wastewater Company grant permission for TWW use to water-consuming industries and man-made forests development, which result in increasing employment, reduction of harmful effects of dust, and water consumption decrease.


Assuntos
Agricultura , Águas Residuárias , Conservação dos Recursos Naturais , Irã (Geográfico) , Abastecimento de Água
10.
Infect Dis Poverty ; 9(1): 124, 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32867851

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19) was confirmed in Brazil in February 2020. Since then, the disease has spread throughout the country, reaching the poorest areas. This study analyzes the relationship between COVID-19 and the population's living conditions. We aimed to identify social determinants related to the incidence, mortality, and case fatality rate of COVID-19 in Brazil, in 2020. METHODS: This is an ecological study evaluating the relationship between COVID-19 incidence, mortality, and case fatality rates and 49 social indicators of human development and social vulnerability. For the analysis, bivariate spatial correlation and multivariate and spatial regression models (spatial lag model and spatial error models) were used, considering a 95% confidence interval and a significance level of 5%. RESULTS: A total of 44.8% of municipalities registered confirmed cases of COVID-19 and 14.7% had deaths. We observed that 56.2% of municipalities with confirmed cases had very low human development (COVID-19 incidence rate: 59.00/100 000; mortality rate: 36.75/1 000 000), and 52.8% had very high vulnerability (COVID-19 incidence rate: 41.68/100 000; mortality rate: 27.46/1 000 000). The regression model showed 17 indicators associated with transmission of COVID-19 in Brazil. CONCLUSIONS: Although COVID-19 first arrived in the most developed and least vulnerable municipalities in Brazil, it has already reached locations that are farther from large urban centers, whose populations are exposed to a context of intense social vulnerability. Based on these findings, it is necessary to adopt measures that take local social aspects into account in order to contain the pandemic.


Assuntos
Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , Determinantes Sociais da Saúde , Adolescente , Brasil/epidemiologia , Criança , Pré-Escolar , Intervalos de Confiança , Infecções por Coronavirus/mortalidade , Educação , Emprego , Humanos , Incidência , Renda , Longevidade , Análise Multivariada , Pandemias , Pneumonia Viral/mortalidade , Pobreza , Análise de Regressão , Saneamento , Esgotos , Condições Sociais , Análise Espacial , Abastecimento de Água/normas , Adulto Jovem
11.
Sci Total Environ ; 737: 140291, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32783865

RESUMO

This paper presents information on the concentration of radioactivity and chemicals at 12 water stations that used groundwater as their raw water supply source. The groundwater's radioactivity was higher than the treated, tap, and surface water, but lower than the national and international recommendations. At five stations (41.7%), the gross alpha contents were higher than the levels advised by Vietnam's regulations, but met the WHO and IAEA's recommendations. The mean activity (Bq L-1) gross alpha, gross beta, Ra-224, Ra-226, and Ra-228 were 0.093 ± 0.012, 0.221 ± 0.020, 0.031 ± 0.004, 0.028 ± 0.004, and 0.035 ± 0.001, respectively. The contribution of Ra-226 to the gross alpha was in a range of 23%-60% (r = 0.91, p value <0.001), and the ratio of Ra-226/Ra-228 ranged from 0.49-1.06. For the treated and tap water, each age groups' annual committed effective dose was lower than the international regulations. The concentration of the total dissolved solids, sulfate, chloride, sodium, barium, and manganese met the national regulations. However, during the rainy season, the surface water in the area was affected by saltwater intrusion, with salinity up to 4.1‰. Discriminant analysis was applied to study the differences among the water groups. As a result, the treated and tap water were separated from the others.


Assuntos
Monitoramento de Radiação , Radioatividade , Poluentes Radioativos da Água/análise , Saúde Pública , Vietnã , Abastecimento de Água
12.
Sci Total Environ ; 737: 140296, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32783866

RESUMO

Disinfection byproducts (DBPs) in drinking water is an issue in many countries. Many DBPs are possible or probable human carcinogens while few DBPs pose cyto- and genotoxic effects to the mammalian cells. The populations are likely to consume DBPs with drinking water throughout their lifetimes. A number of DBPs are regulated in many countries to protect humans. In this study, human exposure, risk and disability-adjusted life years (DALY) were predicted from DBPs in multiple water supply systems, including groundwater (GW), desalinated water (DW) and blend water (BW). The averages of lifetime excess cancer risks from GW, DW and BW were 4.15 × 10-6, 1.75 × 10-5 and 2.59 × 10-5 respectively. The populations in age groups of 0 - <2, 2-16 and >16 years contributed 25.4-25.7%, 28.6-29.6% and 45.0-45.7% to the total risks respectively. The DALY from GW, DW and BW were estimated to be 5.8, 27.0 and 39.9 years, respectively while the corresponding financial burdens were US$ 0.63, 2.93 and 4.34 million respectively. The findings are likely to assist in selecting the supply water sources to better control human exposure and risk from DBPs.


Assuntos
Desinfetantes/análise , Água Potável/análise , Poluentes Químicos da Água/análise , Purificação da Água , Animais , Desinfecção , Halogenação , Humanos , Anos de Vida Ajustados por Qualidade de Vida , Arábia Saudita , Abastecimento de Água
13.
Water Sci Technol ; 81(11): 2281-2290, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32784273

RESUMO

The history of water supply and wastewater engineering in Crete Island (Greece) dates back more than ca 4,500 years, since the early Bronze Ages. In the Minoan era, it was recognized that the removal of wastewater and storm-water were necessary for communal living. The early Minoan developments in wastewater and storm-water collection and removal are the cornerstones on which modern cities are built. The evolution of wastewater and storm-water management from prehistoric to modern times in Crete is examined briefly in this paper. Information on the current status and future strategies for wastewater and storm-water management is also presented.


Assuntos
Águas Residuárias , Água , Cidades , Grécia , Ilhas , Eliminação de Resíduos Líquidos , Abastecimento de Água
14.
J Environ Manage ; 274: 111202, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32784082

RESUMO

In this research, multivariate statistical analysis was performed on twenty water quality parameters (WQP) collected on tri-monthly basis (four times/year) from 441 drinking water sources in Newfoundland and Labrador (NL), Canada for 18 years (1999-2016). The WQP included alkalinity (Alk), color (Col), conductivity (Cond), hardness (Hard), pH, total dissolved solids (TDS), turbidity (Turb), bromide (Br), calcium (Ca), chloride (Cl), fluoride (F), potassium (K), sodium (Na), sulfate (SO4), dissolved organic carbon (DOC), ammonia (NH3), nitrate (NO3), Kjeldahl nitrogen (N), total phosphorus (P) and magnesium (Mg). The assessment was conducted on surface water (SWS) and groundwater (GWS) sources separately. In SWS and GWS, number of samples analyzed for each WQP were in the ranges of 3434-6057 and 1915-1919 respectively. Averages of DOC and pH showed increasing trends (SWS: DOC = 0.0722 mg/L/year; pH = 0.0375 units/year; GWS: DOC = 0.0491 mg/L/year; pH = 0.0441 units/year) while the other WQP showed variable characteristics, which could increase treatment cost and deteriorate tap water quality. Strong correlations were observed for Ca-Hard (r = 0.97-0.98), TDS-Cond (r = 0.91-0.99) and Na-Cl (r = 0.87-0.96). In SWS, Alk had stronger correlations with Cond, Hard, pH, TDS, Ca and Mg (r = 0.62-0.94) than GWS (r = 0.56-0.63). Principal Component Analysis revealed separate clusters for DOC-Col, Na-Cl, TDS-Cond, Ca-Alk and Mg-Hard, indicating that these WQP moved together. In SWS and GWS, six principal components were significant (eigenvalue ≥ 1.0), and explained 74.8% and 72.9% of overall variances respectively. In Factor Analysis, six varifactors explained 73.4% and 70.5% of total variances in SWS and GWS respectively. For SWS and GWS, eleven and ten WQP, respectively explained these variances, indicating 45% and 50% data reduction respectively. The findings can assist in controlling water quality through monitoring reduced number of WQP, which is likely to minimize the monitoring cost.


Assuntos
Água Potável/análise , Água Subterrânea , Poluentes Químicos da Água/análise , Canadá , Monitoramento Ambiental , Análise Multivariada , Terra Nova e Labrador , Qualidade da Água , Abastecimento de Água
15.
J Environ Manage ; 274: 111166, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32835871

RESUMO

Reliance on new and alternative water supply sources is a desirable option for upgrading existing and ageing urban water system infrastructure that is no longer able to cater for steadily increasing water demand. This transformation will increasingly involve the use of decentralised, more complex and energy intensive urban water systems. Modelling capability that takes a holistic systems approach to optimize the dynamic interactions between water and energy is needed to evaluate the performance of fit-for-purpose water supply systems for the urban sector. This paper presents a simulation-optimisation model to concurrently simulate and optimize an urban water supply system based on minimum energy use when water of alternative quality is supplied to different users on a 'fit-for-purpose' basis. The model uses a System Dynamics approach to simulate the energy use of different water supply systems in the form of stocks and flows combined with a Genetic Algorithm (GA) technique to optimize energy use while satisfying all the water demands. The comprehensive model framework is built on a Matlab/Simulink® platform. Life Cycle Energy Assessment (LCEA) is used to generate the embodied energy use variables which are input to the simulation-optimisation model. The model is sufficiently flexible to accommodate water supply systems of variable spatial scales and analyse water and energy use at variable time scales. The application of the modelling framework on the Aurora urban development estate, Australia, shows that the model produces essential information about the water supply and energy use intensity according to specified criteria.


Assuntos
Modelos Teóricos , Água , Austrália , Cidades , Reforma Urbana , Abastecimento de Água
16.
Environ Monit Assess ; 192(8): 558, 2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32740690

RESUMO

The objective of this study is to propose and apply a novel approach to develop a drinking water quality index that enables water managers to routinely identify the vulnerabilities in a distribution system (DS) while taking into account the priorities of water managers and operators. Here, we propose an innovative approach based on the participation of eight researchers and water managers. The input from these participants was included through a combination of the Delphi and MACBETH (Measuring Attractiveness by a Categorical-Based Evaluation Technique) methods, which were applied to an index developed using fuzzy logic. The index was then validated by conducting sensitivity and comparative analyses on a database from field sampling campaigns conducted in various small municipal DSs in two Canadian provinces: Quebec and Newfoundland and Labrador. Finally, the drinking water quality index was applied to a database of the DS in Quebec City, Canada. Sensitivity and comparative analyses revealed that the developed index could allow for the characterization of water sample quality and could prove useful for prioritizing interventions in the DS. The index was also useful for representing the spatial variability of water quality, and provided nuanced information about water quality, especially when the water quality parameter values complied with guidelines and regulations. These results provide a transferable and integrated approach for developing customized drinking water quality indices. This study will help pave the way for water quality managers to better prevent episodes of possible water quality deterioration.


Assuntos
Água Potável , Qualidade da Água , Canadá , Monitoramento Ambiental , Terra Nova e Labrador , Quebeque , Abastecimento de Água
18.
Environ Monit Assess ; 192(9): 607, 2020 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-32860540

RESUMO

The present study aimed to propose a water quality index (WQI) for the Federal District, Brazil, as a management tool for water resources used in irrigation. Irrigated agriculture is a sector that has been growing in the region, with a consequent demand for quality water. One strategy for assessing water quality in rural areas is to adopt monitoring programs, which generate a large amount of data that often needs to be synthesized. The use of indexes is a way of organizing data in a synthetic and easy to understand format. Although initially formulated to assess the quality of drinking water, it is believed that a similar logic can easily be applied to assess the quality of irrigation water. Studies that evaluate the quality of water for irrigation are very common in arid or semi-arid regions, due to the problems of saline water in the soil and crops. On the other hand, the microbiological approach to water is poorly investigated, since contamination of crops can pose a risk to food security. In this work, three water bodies were selected in rural areas due to their preponderant use: irrigation. The monitoring occurred between May 2012 and April 2013 in 9 sampling points. For each sample collected, 22 physical, chemical, and biological parameters were established. Principal component analysis (PCA) was used in the evaluation and selection of water quality variables to compose the WQI. From PCA, it was possible to reduce the number of parameters from 16 to 6 main ones that reflect the water resources characteristics in the region, which were pH, electrical conductivity, total hardness, sodium absorption ratio, nitrate, and Escherichia coli. Of the five classes proposed for WQI, two points were classified as "very good." The other sample points were classified as "good" and "average" for the irrigation practice. The adapted WQI proved to be a good tool in the management of the water quality of the three rivers, and it can be easily used to assess the quality of water for irrigation in the region.


Assuntos
Poluentes Químicos da Água/análise , Qualidade da Água , Irrigação Agrícola , Brasil , Monitoramento Ambiental , Abastecimento de Água
19.
Science ; 369(6507): 1058, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32855327
20.
Braz J Microbiol ; 51(3): 1109-1115, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32809115

RESUMO

COVID-19 has killed more than 500,000 people worldwide and more than 60,000 in Brazil. Since there are no specific drugs or vaccines, the available tools against COVID-19 are preventive, such as the use of personal protective equipment, social distancing, lockdowns, and mass testing. Such measures are hindered in Brazil due to a restrict budget, low educational level of the population, and misleading attitudes from the federal authorities. Predictions for COVID-19 are of pivotal importance to subsidize and mobilize health authorities' efforts in applying the necessary preventive strategies. The Weibull distribution was used to model the forecast prediction of COVID-19, in four scenarios, based on the curve of daily new deaths as a function of time. The date in which the number of daily new deaths will fall below the rate of 3 deaths per million - the average level in which some countries start to relax the stay-at-home measures - was estimated. If the daily new deaths curve was bending today (i.e., about 1250 deaths per day), the predicted date would be on July 5. Forecast predictions allowed the estimation of overall death toll at the end of the outbreak. Our results suggest that each additional day that lasts to bend the daily new deaths curve may correspond to additional 1685 deaths at the end of COVID-19 outbreak in Brazil (R2 = 0.9890). Predictions of the outbreak can be used to guide Brazilian health authorities in the decision-making to properly fight COVID-19 pandemic.


Assuntos
Infecções por Coronavirus/epidemiologia , Previsões/métodos , Pneumonia Viral/epidemiologia , Algoritmos , Brasil/epidemiologia , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/prevenção & controle , Detergentes/provisão & distribução , Educação/estatística & dados numéricos , Humanos , Análise dos Mínimos Quadrados , Dinâmica não Linear , Pandemias/prevenção & controle , Pneumonia Viral/mortalidade , Pneumonia Viral/prevenção & controle , Política , Densidade Demográfica , Pobreza , Fatores Socioeconômicos , Estatística como Assunto , Fatores de Tempo , Abastecimento de Água/normas
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