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1.
J Environ Manage ; 368: 122157, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39128349

RESUMO

With the growing concerns about the protection of ecosystem functions and services, governments have developed public policies and organizations have produced an awesome volume of digital data freely available through their websites. On the other hand, advances in data acquisition through remote sensed sources and processing through geographic information systems (GIS) and statistical tools, allowed an unprecedent capacity to manage ecosystems efficiently. However, the real-world scenario in that regard remains paradoxically challenging. The reasons can be many and diverse, but a strong candidate relates with the limited engagement among the interest parties that hampers bringing all these assets into action. The aim of the study is to demonstrate that management of ecosystem services can be significantly improved by integrating existing environmental policies with environmental big data and low-cost GIS and data processing tools. Using the Upper Rio das Velhas hydrographic basin located in the state of Minas Gerais (Brazil) as example, the study demonstrated how Principal Components Analysis based on a diversity of environmental variables assembled sub-basins into urban, agriculture, mining and heterogeneous profiles, directing management of ecosystem services to the most appropriate officially established conservation plans. The use of GIS tools, on the other hand, allowed narrowing the implementation of each plan to specific sub-basins. This optimized allocation of preferential management plans to priority areas was discussed for a number of conservation plans. A paradigmatic example was the so-called Conservation Use Potential (CUP) devoted to the protection of aquifer recharge (provision service) and control of water erosion (regulation service), as well as to the allocation of uses as function of soil capability (support service). In all cases, the efficiency gains in readiness for plans' implementation and economy of resources were prognosed as noteworthy.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Sistemas de Informação Geográfica , Brasil , Política Ambiental
2.
Environ Manage ; 67(4): 623-631, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33555407

RESUMO

Hydrographic basins are the fundamental unit for the effective territorial planning. However, areas of higher and lesser susceptibility to degrading processes can occur in the same region, where different actions are required to preserve natural resources, as soil and water. In this context, this study aimed to propose a prioritization model to guide the territorial management in hydrographic basins. The study was conducted in the Tarumã River basin, embedded in the southwest region of the São Paulo State, Brazil. First, the basin was compartmentalized into planning units, based on the delimitation and grouping of small watersheds. In each unit, seven morphometric parameters were calculated. The relationships among the parameters were evaluated by principal component analysis, from which the parameters were weighted. It resulted in an index expressing the environmental fragility of the planning units. Among the planning units, 20% present very-high priority, only 5% very-low priority, and 75% low, moderate, and high priority. Units of higher priority are commonly at the basins' headwaters, where linear channels and steeper slopes are concentrated. Lower priority units present low relief and hydrography conditions that do not favor high-intensity erosive processes. The proposed method is effective in identifying regions of high susceptibility to degradation according to morphometric parameters, which should be prioritized on the basins' territorial management. Since these parameters can be easily calculated, it can be presumed that the results could assist the environmental planning and the optimization of natural resources management within different hydrographic basins.


Assuntos
Rios , Solo , Brasil , Monitoramento Ambiental , Recursos Naturais , Água
3.
Environ Monit Assess ; 191(9): 562, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31410581

RESUMO

Human activities have long been altering the natural conditions of streams, including the quality of their water, throughout most of Brazil. This problem is even worse in regions with low rainfall levels, such as the Brazilian Northeast, where water quality needs to be monitored more carefully. In this context, the present study investigated the effects of environmental integrity on the physicochemical characteristics of the streams of the basin of the Itapecuru River in northeastern Brazil. We tested the hypothesis that streams with lower habitat integrity would have higher conductivity, pH, and temperature, due to the reduced input of allochthonous organic matter and the greater washout of sediments to the stream bed. A total of 15 streams, of a sedimentary basin, were evaluated in the municipality of Caxias, in the Brazilian state of Maranhão, between June 2015, and July 2016; each stream was sampled once a month during the drought period in the region, where physicochemical measurements were taken to determine the environmental integrity of the stream through the application of a habitat integrity index. Streams with greater habitat integrity had lower conductivity, pH, and temperature and had higher discharge rates. The index proved to be not an effective tool for the evaluation of water quality, but was found to be important for the management of hydrographic basins by indicating important changes in environmental variables. In this case, the index can be used primarily for the management of hydrographic basins, given that it can be applied straightforwardly, it can be interpreted easily by decision-makers, and it can quantify alterations to the structure of the system with precision.


Assuntos
Monitoramento Ambiental/métodos , Rios/química , Qualidade da Água , Brasil , Ecossistema , Humanos
4.
Can J Neurol Sci ; 45(4): 478-480, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30056823

RESUMO

The association between environmental exposures and Parkinson's disease continues to garner interest. In the late 1980s, Barbeau et al. reported in the Canadian Journal of Neurological Sciences a heterogeneous distribution of Parkinson's disease cases across the province of Québec by hydrographic region. Here we report the findings of a validation study based on data obtained from the Québec medication insurance program-information which was unavailable to the previous group. Similar to Barbeau et al., our analysis showed a heterogeneous distribution of cases across the province with higher prevalence in the same region of interest, in addition to other areas.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Doença de Parkinson/epidemiologia , Prevalência , Antiparkinsonianos/uso terapêutico , Feminino , Humanos , Masculino , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/etiologia , Quebeque/epidemiologia
5.
J Environ Manage ; 217: 710-717, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29654974

RESUMO

Over the past few years, many sectors such as energy generation, industry, domestic supply, and agriculture have encountered serious environmental problems due to the lack of rainfall. Thus, the purpose of this paper is to review the current methodology of royalties distribution from Itaipu hydroelectric plant. In the proposed approach, two criteria were considered to establish the division of Itaipu royalties: (1) the relative percentage of the water flow in the generation of electricity and, (2) the relative percentage of the drop in the height of water. 62 hydroelectric plants were evaluated in this study. In 52 plants the water flow was the factor that most contributed to the generation of electricity. In 2013, 346 municipalities benefited the Itaipu royalties. With the proposed methodology, 1,327 municipalities will receive the resource, what would increase the revenue of each of these municipalities by, on average, US$ 87,436.91 per year. The methodology presented herein proposes a reduction in the environmental disparity that now exists in Brazil, through improvement to Government instruments and environmental policies. The distribution of royalties throughout the watershed can provide additional resources to support payment programs for environmental services at the state and municipality levels.


Assuntos
Agricultura , Centrais Elétricas , Brasil , Indústrias
6.
Sci Total Environ ; 875: 162499, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36871736

RESUMO

The intensive use of glyphosate around the world in the last few decades demands constant monitoring of this compound and its metabolite in aquatic compartments. This work aimed to develop a sensitive method for the analysis of glyphosate, AMPA and glufosinate in water by liquid chromatography/tandem mass spectrometry (LC-MS/MS). The method involves analyte concentration by lyophilization (20×) and direct injection on the LC-MS/MS, and was satisfactorily validated at a LOQ of 0.0025 µg L-1. A total of 142 samples of surface and groundwater collected during the 2021/2022 dry and rainy seasons in the Rio Preto Hydrographic Basin were analyzed. All the 52 groundwater samples were positive for glyphosate (up to 1.5868 µg L-1, dry season) and AMPA (up to 0.2751 µg L-1, dry season). A total of 27 of the 90 surface water samples were positive for glyphosate (up to 0.0236 µg L-1), and 31 samples for AMPA (up to 0.0086 µg L-1), of which over 70 % collected during the dry season. Glufosinate was detected in only five samples, four in groundwater (up to 0.0256 µg L-1). The levels found in the samples are much lower than the maximum levels established by the Brazilian legislation for glyphosate and/or AMPA and lower than the most critical toxicological endpoints for aquatic organisms. However, constant monitoring is necessary, demanding sensitive methods to allow the detection of the very low levels of these pesticides in water.

7.
Chemosphere ; 283: 131157, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34182633

RESUMO

On November 5th, 2015, a mining dam spilled a huge plume of mining waste in the Doce River. Even though many studies have reported the environmental impact from the Doce River's tragedy, the transport of potentially toxic elements (PTE) by kinetic modeling to determine how long the basin takes to achieve the natural balance has not been described. Therefore, samples of sludge, sediment, and water were collected along the Doce River basin, to assess the elements' total leaching by kinetic modeling. The elements Fe, Al, Mn, Cu, Ag, Pb, Cd, and As were evaluated. An innovative mobilization factor (FS/D) indicated that Mn2+, Ag+, and Cd2+ can be mobilized about 80, 89, and 57 times more than its initial concentration. Besides, in low pH, the Al and Pb ions can be mobilized. The desorption kinetics showed a lower rate constant (k) and higher initial desorption constant (h) for Mn2+ than Cd2+ and Ag+, suggesting both high- and low-affinity interaction sites for Mn2+. The exponential decay demonstrated that metals can leach for months or years. Thus, the long-lasting release of metals from mining tailing waste in concentrations that endanger the ecosystem and human health makes clear the need for long-term monitoring.


Assuntos
Desastres , Metais Pesados , Poluentes Químicos da Água , Brasil , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos , Humanos , Cinética , Metais Pesados/análise , Rios , Poluentes Químicos da Água/análise
8.
Eng. sanit. ambient ; 26(1): 45-51, jan.-fev. 2021. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1154123

RESUMO

RESUMO Objetivou-se, com este estudo, avaliar o impacto ambiental do uso e da ocupação da terra na qualidade da água da bacia hidrográfica do rio Desquite, utilizando a Resolução nº 357/2005, do Conselho Nacional do Meio Ambiente (CONAMA), como legislação balizadora. Foram realizadas coletas de água e determinados os parâmetros físico-químicos: temperatura, pH, condutividade elétrica, oxigênio dissolvido (OD) e sólidos totais dissolvidos (STD), com uma sonda multiparâmetro; demanda química de oxigênio (DQO), fenóis totais, fósforo total e amônia (NH3), com um fotocolorímetro; e os metais cádmio (Cd), chumbo (Pb), cromo (Cr), níquel (Ni) e cobre (Cu), por meio de Espectrometria de Absorção Atômica de Alta Resolução com Fonte Contínua (AR-FC EAA). Para efeitos comparativos, tomando-se como base o ordenamento jurídico, as amostras apresentaram valores acima dos valores máximos permitidos (VMP) para os parâmetros fósforo total, NH3 e Cr. Também foram observadas alterações nos parâmetros: OD, fenóis totais, DQO e Cd. Ao final de um ano de acompanhamento e campanhas amostrais, conclui-se que o rio Desquite seria classificado de acordo com os limites estabelecidos para a classe IV da Resolução CONAMA nº 357/2005, e verificou-se que as principais alterações na qualidade da água ocorrem nas áreas de preservação permanente com ausência de cobertura vegetal ou nos lançamentos de efluentes domésticos e resíduos sólidos nesses locais ou diretamente nos corpos d'água.


ABSTRACT The objective of this study was to evaluate the environmental impact of land use and occupation on the water quality of the Desquite river basin, using CONAMA Resolution no 357/2005, as beacon legislation. Water samples were collected and the physical-chemical parameters were determined: temperature, pH, electrical conductivity, DO and TDS, with a multiparameter probe; COD, total phenols, total phosphorus and ammonia (NH3) with a Photocolorimeter; and the metals Cd, Pb, Cr, Ni and Cu were determined by Continuous Source High Resolution Atomic Absorption Spectrometry (HR-FC EAA). Based on the comparative legal order, the samples presented values above the maximum permitted values for the parameters total phosphorus, ammonia (NH3) and Cr. Changes were also observed in the parameters: OD, total phenols, COD and Cd. At the end of a year of follow-up and sampling campaigns, it was concluded that the Desquite river would be classified according to the limits established for class IV of CONAMA Resolution no 357/2005, the main changes in water quality occur in the areas of permanent preservation with absence of vegetal cover or in the releases of domestic effluents and solid residues in these places or directly in the bodies of water.

9.
Eng. sanit. ambient ; 25(5): 777-787, set.-out. 2020. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1142903

RESUMO

ABSTRACT The protozoa Cryptosporidium spp. and Giardia spp. are etiological agents responsible for the transmission of gastroenteritis, mainly due to the consumption of contaminated water. Their (oo)cysts are resistant to adverse environmental conditions, as well as to most conventional water treatment processes. Thus, the objective of this work was to evaluate the occurrence of (oo)cysts of these protozoans in surface water collected for human consumption in the state of Goiás, Brazil. Fifteen samples of raw water were collected to assess the occurrence of (oo)cysts of the protozoa using the Membrane Filtration method, in addition to turbidity and pH analyses. Recovery rates in tests with ultrapure water reached the USEPA (2012) criteria for Giardia (78.1% ± 0%) and for Cryptosporidium (60.6% ± 32.6%); however, recovery in raw water was lower due to turbidity. All samples (n = 15) were positive for Cryptosporidium spp. oocysts, with a maximum concentration of 250 oocysts/L, demonstrating that these protozoa are disseminated in the aquatic environment of the state of Goiás and pose a risk to public health. Due to the use of water sources for public consumption, it is recommended that public authorities and sanitation companies act to preserve and maintain water courses, carry out periodic monitoring of treatment plants that supply the Cerrado, Santana and São Manoel streams and improve existing treatment technologies. The results did not allow to infer whether animal load and grazing area promote an increase in contamination of the lotic aquatic systems.


RESUMO Os protozoários Giardia spp. e Cryptosporidium spp. são agentes etiológicos responsáveis pela transmissão de gastroenterites, principalmente por causa do consumo de água contaminada. Seus (oo)cistos são resistentes às condições ambientais adversas, bem como à maioria dos processos convencionais de tratamento da água. Assim, o objetivo deste trabalho foi avaliar a ocorrência de (oo)cistos desses protozoários em águas superficiais captadas para consumo humano no estado de Goiás, Brasil. Quinze amostras de água bruta foram coletadas para avaliar a ocorrência de (oo)cistos dos protozoários pelo método de Filtração por Membrana, além da análise de turbidez e pH. As taxas de recuperação nos testes com água ultrapura atingiram os critérios da USEPA (2012) para Giardia (78.1 ± 0%) e para Cryptosporidium (60.6 ± 32.6%), entretanto, em água bruta, a recuperação foi inferior devido à turbidez. Todas as amostras (n = 15) foram positivas para oocistos de Cryptosporidium spp., com valor máximo de 250 oocistos/L, demonstrando que esses protozoários se disseminam no meio aquático do estado de Goiás e geram risco à saúde pública. Devido à utilização de mananciais para consumo público, recomenda-se que as autoridades públicas e as empresas de saneamento atuem na preservação e manutenção dos cursos d'água, realizem o monitoramento periódico das plantas de tratamento que realizam adução no Córrego Cerrado, Córrego Santana e Córrego São Manoel e aprimorem as tecnologias de tratamento existente. Os resultados não permitiram inferir se a carga de animais e a área de pastagem promove o aumento da contaminação dos sistemas aquáticos lóticos.

10.
Rev. luna azul ; (42): 235-255, ene.-jun. 2016. ilus, graf, mapas, tab
Artigo em Espanhol | LILACS | ID: lil-791185

RESUMO

Los problemas ambientales que afectan a las cuencas hidrográficas en Colombia tienen múltiples causas, una de ellas es la ausencia de una cultura ambiental en las comunidades que viven o frecuentan zonas aledañas a las corrientes hídricas. El principal objetivo de este trabajo era recopilar la percepción local sobre el estado ambiental de la cuenca baja del río Manzanares, ubicada en el departamento del Magdalena e incentivar a los pobladores a reflexionar sobre su papel frente a la solución de las principales problemáticas. Para lograr este objetivo se utilizaron diferentes herramientas metodológicas, 1) Encuesta dirigida a los pobladores de la zona, 2) talleres participativos con estudiantes, 3) desarrollo de recorridos de reconocimiento ambiental y territorial. A través de estos últimos se recopiló la percepción de los participantes sobre componentes ambientales básicos: agua, aire, suelo, flora, fauna y saneamiento básico. Se realizaron dos recorridos con grupos diferentes, teniendo un total 50 estudiantes del grado décimo de un colegio ubicado en la zona de estudio y algunos estudiantes universitarios. A través de este estudio se encuentra que la principal problemática percibida por la comunidad de la cuenca baja del río Manzanares en Santa Marta, es la contaminación del agua por el aporte de aguas residuales y la disposición no controlada de residuos sólidos; esta última causa, ligada a la falta de una cultura ambiental no solo en los residentes de la ciudad sino también en sus visitantes.


Environmental problems affecting hydrographic basins in Colombia are generated by multiple factors, being one of them the lack of environmental culture in local communities living in adjacent areas to the water currents. The main objective of this work was to compile the local community perception about the environmental status of the lower basin of the Manzanares River, located in the department of Magdalena, and to encourage settlers to reflect on their role for the solution of the major problems. In order to achieve this objective, different methodological tools were used: 1) A survey with local people, 2) participatory workshops with students, and 3) environmental and territorial recognition routes. By using these tools, it was possible to collect the perception of the participants about basic environmental components: water, air, soil, flora, fauna and basic sanitation. Two routes were done with different groups and a total of 50 tenth grade students from a school in the area and some university students. This study found that the main environmental problem that the community of the lower basin of the Manzanares river in Santa Marta perceives is water pollution generated by the supply of wastewater and by the uncontrolled disposal of solid wastes; this last cause is linked to the lack of environmental culture, not only in the city residents but also in its visitors.


Assuntos
Humanos , Pessoa de Meia-Idade , Percepção , Poluição da Água , Bacias Hidrográficas , Colômbia
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