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1.
Water Sci Technol ; 80(3): 466-477, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31596258

RESUMO

Wetlands are among the most productive ecosystems that provide services ranging from flood control to climate change mitigation. Wetlands are also critical habitats for the survival of numerous plant and animal species. In this study, we used satellite remote sensing techniques for classification and change detection at an internationally important wetland (Ramsar Site) in Turkey. Sultan Marshes is located at the center of semi-arid Develi closed basin. The wetlands have undergone significant changes since the 1980s due to changes in water flow regimes, but changes in recent years have not been sufficiently explored yet. In this study, we focused on the changes from 2005 to 2012. Two multispectral ASTER images with spatial resolution of 15 m, acquired on June 11, 2005 and May 20, 2012, were used in the analyses. After geometric correction, the images were classified into four information classes, namely water, marsh, agriculture, and steppe. The applicability of three classification methods (i.e. maximum likelihood (MLH), multi-layer perceptron type artificial neural networks (ANN) and support vector machines (SVM)) was assessed. The differences in classification accuracies were evaluated by the McNemar's test. The changes in the Sultan Marshes were determined by the post classification comparison method using the most accurate classified images. The results showed that the highest overall accuracy in image classifications was achieved with the SVM method. It was observed that marshes and steppe areas decreased while water and agricultural areas expanded from 2005 to 2012. These changes could be the results of water transfers to the marshes from neighboring watershed.


Assuntos
Monitoramento Ambiental/métodos , Máquina de Vetores de Suporte , Áreas Alagadas , Conservação dos Recursos Naturais , Ecossistema , Eugenol , Redes Neurais (Computação) , Turquia , Óxido de Zinco
2.
An Acad Bras Cienc ; 91(3): e20180748, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31596390

RESUMO

OBJECTIVE: the aim of this study is to map thermal stress risks for human health at the São Francisco River Basin (SFRB) in the Semiarid region, for climatic scenarios RCP 4.5 and 8.5. METHODS: The heat stress conditions were defined by the Wet Bulb Globe Temperature (WBGT) indicator and by the average number of annual days in which the WBGT values exceeded the 90th percentile of the reference period. The WBGT was estimated for the climate scenarios RCP 4.5 (intermediate) and 8.5 (pessimistic) for the period 2011-2090 comparing to the period of reference (1961-2005). RESULTS: The projections show that for the pessimistic scenario practically all municipalities of the SFRB region can reach values of WBGT that indicate a high risk for heat stress in the period 2071-2099. For this same scenario and period, the municipalities of the Lower and Under-average regions may present values of WBGT above the 90th percentile of the reference period in more than 90% of the days/year. CONCLUSIONS: These results show that, if the emission of greenhouse gases continues in the present proportions, some municipalities of the SFRB region may present a high risk for heat stress affecting the work capacity and the practice of physical exercises.


Assuntos
Monitoramento Ambiental/métodos , Transtornos de Estresse por Calor/etiologia , Temperatura Alta/efeitos adversos , Brasil , Cidades , Exercício/fisiologia , Ocupações em Saúde , Humanos , Umidade , Exposição Ocupacional , Fatores de Risco
3.
An Acad Bras Cienc ; 91(3): e20180692, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31618411

RESUMO

The assessment of biotic-habitat relationships provides key information to predict biotic responses to perturbations and important tools for river management and monitoring. This study aimed to assess the spatial distribution of Ephemeroptera and Trichoptera in mountain streams of central Argentina. We evaluated the effect of seasonality and identified the variables conditioning the abundance of the assemblages and the habitat with the highest taxonomic richness. Sampling was carried out in four streams (Carcarañá River basin) during high and low water periods. Three lotic habitats were sampled: riffles, coarse substrate runs, and fine substrate runs; and physicochemical and habitat variables were measured. We found differences in assemblage composition, among the 25 genera of Ephemeroptera and Trichoptera, at the habitat level. The most important variables affecting distribution patterns were substrate and flow type, but macroalgae and organic matter (twigs, leaves, and detritus) were also important predictors. Riffles maintained the highest richness but when considering only the Ephemeroptera taxa, fine substrate runs emerged also as an important habitat for these taxa. Our study provided valuable ecological information related to habitat preference of taxa with a key role in stream functioning and of great usefulness for the monitoring of lotic systems.


Assuntos
Ecossistema , Monitoramento Ambiental/métodos , Ephemeroptera/fisiologia , Neópteros/fisiologia , Rios , Animais , Argentina , Ephemeroptera/classificação , Neópteros/classificação , Análise de Componente Principal , Especificidade da Espécie
4.
Sci Total Environ ; 692: 1005-1021, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31539933

RESUMO

Temporal and spatial atmospheric deposition trends of elements to the boreal forest surrounding bitumen production operations in the Athabasca Oil Sands Region (AOSR), Alberta, Canada were investigated as part of a long-term lichen bioindicator study. The study focused on eight elements (sulfur, nitrogen, aluminum, calcium, iron, nickel, strontium, vanadium) that were previously identified as tracers for the major oil sand production sources. Samples of the in situ epiphytic lichen Hypogymnia physodes were collected in 2002, 2004, 2008, 2011, 2014, and 2017 within a ~150 km radius from the center of surface oil sand production operations in the AOSR. Site-specific time series analysis conducted at eight jack pine upland sites that were repeatedly sampled generally showed significant trends of increasing lichen concentrations for fugitive dust linked elements, particularly at near-field (<25 km from a major oil sands production operation) sample locations. Multiple regional scale geostatistical models were developed and evaluated to characterize broad-scale changes in atmospheric deposition based on changes in H. physodes elemental concentrations between 2008 and 2014. Empirical Bayesian kriging and cokriging lichen element concentrations with oil sands mining, bitumen upgrading, coke materials handling, and limestone quarry/crushing influence variables produced spatial interpolation estimates with the lowest validation errors. Gridded zonal mean lichen element concentrations were calculated for the two comprehensive sampling years (2008, 2014) and evaluated for spatial and temporal change. Lichen sulfur concentrations significantly increased in every grid cell within the domain with the largest increases (44-88%) in the central valley in close proximity to the major surface oil sand production operations, while a minor nitrogen concentration decrease (-20%) in a single grid cell was observed. The areal extent of fugitive dust element deposition generally increased with significantly higher deposition to lichens restricted to the outer grids of the enhanced deposition field, reflecting new and expanding surface mining activity.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Líquens/química , Alberta , Atmosfera , Poeira/análise , Campos de Petróleo e Gás
5.
Sci Total Environ ; 692: 1234-1241, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31539954

RESUMO

The water quality from rivers near to cities has decreased drastically over the decades due to the environmental pollution. The Ocoa River on its way through the Villavicencio city, Colombia, receives large volumes of domestic and industrial wastewater. In order to establish the effect of the contamination, biochemical and histopathology biomarkers were evaluated in the gills and the liver of two native fish species. Astyanax gr. bimaculatus and Aequidens metae were caught in three sites of the Ocoa River (S1, S2 and S3) and in a reference River during the rainy and dry season. A. metae showed to be more sensitive to water pollution. In general, the rainy season induced a greater negative impact in the fish monitored. At site S3 (after crossing the city where urban runoff and industrial effluents are discharge and close to a landfill), increased inhibition of the antioxidant response and lipid membranes damage were observed; in addition, in this site the histopathological alterations were greater in both fish species. The impact observed in this study on fish health provoked for the Ocoa River contamination demands the need to begin strategies to solve the problem of discharge of domestic and industrial wastewater in aquatic environments in Colombia.


Assuntos
Characidae , Ciclídeos , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/toxicidade , Animais , Colômbia , Poluentes Químicos da Água/análise , Qualidade da Água
6.
Chemosphere ; 235: 1125-1133, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31561303

RESUMO

In many cases, stormwater compliance monitoring is labor intensive, expensive, and largely unsuccessful in providing the data needed to support stormwater management goals. To help address these issues, diffusive gradients in thin film (DGTs), time-integrative passive samplers for metals, were evaluated to monitor copper in stormwater runoff. DGTs were co-located with traditional autosamplers within the stormwater conveyance systems at Naval Base San Diego (NBSD) to provide a direct comparison with composite sampling. DGTs were exposed in the laboratory to flow-averaged composite samples from NBSD stormwater conveyance systems. These experiments showed increasing uptake over time (range = 1.5-24 h) for copper, with positive, linear correlations (r2 > 0.980) between exposure duration and copper mass accumulated. However, it appears that the corresponding calculations of the DGT-labile fraction (CDGT) relative to the dissolved fraction fluctuated across the different exposure durations. In general, trends observed for CDGT measurements from the field were consistent with trends in the lab DGT exposures and traditional dissolved metal measurements from composite samples. Finally, time-weighted average copper concentrations from DGTs deployed for the first and second phases of storm events were within 30% of measurements from DGTs that were deployed for the entire storm event in the same stormwater vault. Cumulatively, these results show promise for continuous monitoring with DGTs as an approach that produces data more representative of exposure to the receiving environment during episodic events than data from traditional grab or composite chemistry sampling, and can represent significant cost savings.


Assuntos
Cobre/análise , Chuva/química , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Metais/análise , Reprodutibilidade dos Testes
7.
Ecotoxicol Environ Saf ; 182: 109458, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31398784

RESUMO

Acid mine drainage (AMD) is a significant contributor of metal pollution leading to ecosystem damage. Bioindicator organisms such as intertidal brown macroalgae have an important role in quantifying the risks of metal bioaccumulation in coastal locations exposed to AMD contamination. Measurement of As, Cd, Cu, Fe, Pb, and Zn accumulation was performed in Fucus serratus, Fucus vesiculosus and Ascophyllum nodosum sampled from two marine locations near to an abandoned Cu mine in Anglesey, Wales, UK. Transect samples were taken from a coastal location (Amlwch) that has seen a substantial increase in AMD contamination over 15 years, in comparison to a nearby estuarine location (Dulas Estuary leading to Dulas Bay) with a historic legacy of pollution. These were compared with samples from the same sites taken 30 years earlier. Some of the Dulas macroalgae samples had Cd, Cu and Zn concentrations that were above background but in general indicated a non-polluted estuary in comparison to substantial pollution over previous decades. In contrast, Fucus samples collected from directly below an AMD outflow at Amlwch showed extremely elevated metal bioaccumulation (>250 mg Fe g-1, >6 mg Cu g-1, >2 mg Zn g-1, >190 µg As g-1) and evidence of macroalgae toxicity, indicating severe pollution at this site. However, the pollution dispersed within 200 m of the outflow source. This study has demonstrated the efficiency of three brown macroalgae species as indicators for metal bioavailability at high spatial resolution and over time.


Assuntos
Monitoramento Ambiental/métodos , Recuperação e Remediação Ambiental , Metais/análise , Mineração , Poluentes Químicos da Água/análise , Biomarcadores Ambientais , Poluição Ambiental , Metais Pesados/análise , Alga Marinha , País de Gales
8.
Environ Monit Assess ; 191(9): 531, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375926

RESUMO

Microbially produced biosurfactants are fast catching up due to their environment-friendly approach over chemical surfactants. But their commercial production is restricted due to poor economy of the production process which could be improved by using high yielding microbial strains and optimizing the process parameters. The present research was directed to optimize the biosurfactant production monitored in terms of oil displacement and emulsification (E24) index, using a promising yeast Meyerozyma guilliermondii YK32. Maximum oil displacement equaling 7.5 cm was obtained with olive oil at 8% (v/v) concentration as carbon source under shaking conditions (150 rpm). Diesel being a complex hydrocarbon was not utilized easily by yeast and showed poor biosurfactant production. Yeast extract at 1.5% (w/v) concentration yielded maximum biosurfactant as evident from maximum oil displacement and E24 index equal to 8.1 cm and 52.6%, respectively. Sodium chloride at the rate of 3% (w/v) supported maximum oil displacement (8.8 cm) using the production broth containing optimized carbon and nitrogen sources. Any increase beyond this level negatively influenced the biosurfactant production. The yield was at its maximum at 30 °C as a shift in temperature either to 35 °C or 25 °C decreased the oil displacement from 8.8 to 5.2 or 7.6 cm, respectively. At 40 °C, oil displacement was decreased to 2.5 cm. Biosurfactant production appeared to be sensitive to varying pH as evident from the E24 index as high as 67.3% at pH 6.0 as compared with 60.2%, 60.1%, and 52.4% at pH 5.0, 5.5, and 7.0, respectively. Yeast biomass yield equivalent to 10.3 g/L and 8.3 g/L was recorded at pH 6 and 7, respectively, during the production process. Elimination of shaking reduced the E24 index from 67.3 to 34.8% under optimized conditions.


Assuntos
Monitoramento Ambiental/métodos , Saccharomycetales/metabolismo , Tensoativos/metabolismo , Biomassa , Carbono/metabolismo , Hidrocarbonetos/metabolismo , Nitrogênio/metabolismo , Saccharomycetales/crescimento & desenvolvimento , Temperatura Ambiente
9.
Environ Monit Assess ; 191(9): 532, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375933

RESUMO

Macajalar Bay in the southern Philippines has become an attractive thoroughfare with recent developments, rendering anthropogenic input to the coastal waters. Expediting coastal resource management strategies necessitates the present study on coastal water characteristics. This was aided with distribution pattern and multivariate analyses for apportioning possible anthropogenic inputs. A total of 15 biophysicochemical characteristics were studied covering two municipalities (Opol and Jasaan) with six subcoastal communities in 2017. Data were all processed for Q test to eliminate outliers before distribution analyses using univariate (descriptive), inferential (t test, one-way ANOVA, Pearson correlation), and multivariate statistics (hierarchal cluster analysis (HCA) and principal component analysis (PCA)). Overall, higher concentrations were determined in the ecotourism site (Opol) than in the industrial site (Jasaan) as sampling months progressed except for oil and grease. Results for total coliform, fecal coliform, heterotrophic plate count (HPC), total suspended solids (TSS), chemical oxygen demand (COD), and oil and grease regardless of spatial-temporal variations exceeded the standards. Distribution pattern revealed variations selectively for pH, temperature, dissolved oxygen (DO), and oil and grease, indicating site-specific distribution. HCA and PCA results corroborated correlation matrices showing elevated concentrations in an ecotourism site (Opol) apportioned anthropogenic input mainly due to rural development and ecotourism. Likewise, in the industrial site (Jasaan), HCA and PCA results reflected possible anthropogenic input from rural development and industries. Overall, anthropogenic apportionment in the bay was influenced by rural development, ecotourism, and industries.


Assuntos
Baías/química , Monitoramento Ambiental/métodos , Atividades Humanas , Poluição da Água/análise , Análise da Demanda Biológica de Oxigênio , Análise por Conglomerados , Monitoramento Ambiental/estatística & dados numéricos , Análise Multivariada , Filipinas , Análise de Componente Principal , Temperatura Ambiente , Urbanização
10.
Environ Monit Assess ; 191(9): 533, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375936

RESUMO

Long-term increased nutrient influx into normally nutrient-limited peatlands in combination with altered hydrological conditions may threaten a peatland's carbon storage function and affect its greenhouse gas (GHG) budget. However, in situ studies on the effects of long-term altered conditions on peatland functioning and GHG budgets are scarce. We thus quantified GHG fluxes in a peatland exposed to enhanced water level fluctuations and long-term nutrient infiltration in Ontario, Canada, via eddy-covariance and flux chamber measurements. The peatland was a prominent sink of - 680 ± 202 g carbon dioxide (CO2) and a source of 22 ± 8 g methane (CH4) m-2 year-1, resulting in a negative radiative forcing of - 80 g CO2 eq. m-2 y-1. During the growing season CH4 fluxes were constantly high (0.1 g m-2 s-1). Further, on three dates, we measured nitrous oxide (N2O) fluxes and observed a small flux of 2.2 mg m-2 day-1 occurring during the thawing period. Taking the studied ecosystem as a model system for other peatlands exposed to long-term increased nutrient infiltration and enhanced water level fluctuations, our data suggest that such peatlands can maintain their carbon storage function and CO2 sequestration may outweigh emissions of CH4.


Assuntos
Sequestro de Carbono , Monitoramento Ambiental/métodos , Gases de Efeito Estufa/análise , Metano/análise , Ciclo Hidrológico , Dióxido de Carbono/análise , Ecossistema , Óxido Nitroso/análise , Ontário , Estações do Ano
11.
Environ Monit Assess ; 191(9): 535, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375991

RESUMO

Selecting the appropriate land use is one of the most important steps toward achieving sustainable development. The main objective of this research is to develop a new method to overcome the contradiction occurring when using the conventional methods to evaluate land suitability for newly reclaimed areas. A spatial model was developed to assess land suitability for wheat in El-Minia Governorate, Egypt, using integration of modeling and geographic information systems-based multi-criteria decision analysis (GIS-MCDA). Land suitability for wheat was performed using two approaches, namely the proposed model (GIS-MCDA) and the parametric method (square root). According to the square root, 75.0% of the study area was classified as not suitable, while the proposed model revealed that 20.5% of the study area was classified as highly suitable and 61.5% as moderately suitable. In order to examine the validity of the proposed model, a comparison was made between the obtained results of both the proposed model and the square root method with the actual yield of the wheat. The correlation coefficient (r) between actual yield and the estimated yield of the square root method was 0.46, while the proposed model gives higher value (r = 0.95), which proves the validity of the proposed model in estimating land suitability for wheat cultivation. The findings of this research revealed that the integration of modeling and GIS-MCDA adopted by the proposed model provides an effective and flexible technique contributing to improve land suitability assessment for wheat in newly reclaimed areas to be more accurate and reliable.


Assuntos
Técnicas de Apoio para a Decisão , Monitoramento Ambiental/métodos , Modelos Teóricos , Desenvolvimento Sustentável , Egito , Sistemas de Informação Geográfica
12.
Environ Monit Assess ; 191(9): 534, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31376029

RESUMO

An assessment of mobility and bioavailability of trace elements present in the soil requires the determination of these elements in soil samples by an appropriate methodology. In such a context, the use of mild extraction reagents-such as water-is considered to be appropriate. On the other hand, performing an analysis of a reference material together with real samples is recommended in order to control the quality of analytical procedure. The quantification of 27 analytes in aqueous extracts of the soil CRMs samples is described. The methodology consisted of single-step extraction of analytes by deionized water (m/v = 1/10) with their subsequent direct determination by inductively coupled plasma-atomic emission spectrometry (ICP-OES). Three certified reference materials (CRM) for soils have been selected as model samples: NCS DC 77302 (alias GBW 07410), Metranal-31, and Metranal-33. Although the recoveries of the selected elements obtained by water extractions are very low (i.e., the values usually do not exceed 1%), the results obtained in this study reveal the elements that by means of ICP-OES can be quantified in the water extracts of unpolluted soils are as follows: Al, Ba, Ca, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, S, Sr, Ti, and V. However, ICP-OES is not sensitive enough to quantify the elements As, Be, Cd, Co, Pb, Sb, Se, Tl, and Zn that are present in the water extracts of clean soil samples in too low mass fractions. The results obtained in this paper are useful for future uses of the three tested CRMs, in the cases of the extraction of the analytes by deionized water at room temperature.


Assuntos
Monitoramento Ambiental/métodos , Metaloides/análise , Metais/análise , Solo/química , Oligoelementos/análise , Água/química , Extração Líquido-Líquido , Espectrofotometria Atômica
13.
Environ Monit Assess ; 191(8): 526, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31363853

RESUMO

Biomonitoring has been used to disclose the public health impact of contaminated sites. This study aimed at setting up good practices to apply biomonitoring targeting animal matrixes to design risk-based surveillance and exposure assessment plans. A nine-step protocol targeting farmed animals was devised and tested in three case study areas including (1) a waste dump, (2) a waste incinerator, and (3) a secondary aluminum smelter. Between 2010 and 2012, in each study area, the following 9-step best practices were applied: hazard identification, GIS project creation, risk area delimitation, control area selection, receptors (livestock) identification, farms and matrixes selection, sampling study design, on-farm secondary sources exclusion, and statistical and geostatistical analysis. Dairy farms and free-range laying hens were the primary targets: eggs from both risk and control areas and milk from risk areas were sampled and submitted for detection of selected tracking contaminants compatible with the putative sources. Comparison data (risk vs. control) of heavy metal concentrations in eggs were available only for case study 2, whereas egg comparison data of persistent organic pollutants were available for all the risk-control pairs. After taking into account potential secondary sources, no concern from metals was arisen, whereas high concentrations of persistent organic pollutants were detected in all risk areas; however, only for the aluminum smelter case study, the contamination was broad and higher in the risk area compared with the control one. The protocol has proved to be easily applicable and flexible to varying contexts and able to provide helpful data to inform risk management decisions.


Assuntos
Ovos/análise , Monitoramento Ambiental/métodos , Monitoramento Ambiental/normas , Poluentes Ambientais/análise , Metais Pesados/análise , Leite/química , Animais , Bovinos , Galinhas , Feminino , Sistemas de Informação Geográfica , Itália , Medição de Risco , Instalações de Eliminação de Resíduos
14.
J Nurs Adm ; 49(9): 418-422, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31436739

RESUMO

The need for continuous observation (1:1) of patients for safety precautions, including fall risk, elopement risk, confusion, and aggressive behavior, is highly variable, and it is therefore difficult to plan accurate staffing levels. The high variability in determining when 1:1 staffing for safety is indicated, and for how long, leads to resource strain and high cost to the hospital. A multidisciplinary team analyzed current processes for assigning, monitoring, and discontinuing safety 1:1 care for nonsuicidal patients using Six Sigma methodologies. The team implemented a standardized weaning process to reduce the duration of time on continuous observation and a standardized 4-hour reassessment using a behavior observation-tracking tool to validate the continued need for 1:1 coverage. The interventions resulted in reducing average monthly safety 1:1 staffing hours by 25.6% and saving an estimated $142 000 annually across 6 units. Phase 2 of the project integrated the observation-tracking tool and reassessment check-in into the hospital's electronic medical record for improved tracking and documentation.


Assuntos
Monitoramento Ambiental/economia , Monitoramento Ambiental/métodos , Segurança do Paciente/economia , Gestão da Segurança/economia , Gestão da Segurança/organização & administração , Gestão da Qualidade Total/organização & administração , Eficiência Organizacional , Humanos , Pennsylvania , Projetos Piloto
15.
An Acad Bras Cienc ; 91(supp 3): e20190445, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365613

RESUMO

If we consider Drosophilidae, the answer to the question above is yes. Many research groups in Brazil and abroad have been showing that assemblages of flies of this family can reflect environmental alteration levels caused by urbanization, and/or by other human disturbances. I will present here a summary of our findings in Drosophilidae assemblages reflecting different degrees of environmental perturbation. These studies were done by graduate students of two post graduate programs of UFRGS, under my supervision, along several decades. I will also present the results stemming from the effort of other Brazilian Drosophilid study groups while identifying the members of those assemblages in different Biomes. As a result of those field studies, several biological invasions were detected and many new important biological problems arose prone to be investigated by genetic, molecular biology and other related approaches.


Assuntos
Drosophilidae/fisiologia , Monitoramento Ambiental/métodos , Animais , Brasil , Drosophilidae/classificação , Densidade Demográfica , População Urbana
16.
Environ Monit Assess ; 191(9): 542, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31385044

RESUMO

The river Ganges, the National Heritage, and the lifeline of millions of Indians, unfortunately, ranked the second most polluted rivers of the world in 2017. This review reveals the current trends of the water quality of the Ganges assessed around 36 stretches during 2012-2016, to indicate an improvement around 6 (16.7%), deterioration around 14 (38.9%), and non-significant changes around 16 (44.4%) stretches. An increase in dissolved oxygen and a decrease in biochemical oxygen demand were observed at six stretches (Devprayag [S5], Rishikesh upstream [S7], Varanasi upstream [S19], Mokama upstream [S25], Mokama downstream [S26], and Munger [S27]). The total and fecal coliform contamination decreased at seven stretches (Rudraprayag [S2 and S3], Devprayag [S5 and S6], Rishikesh [S7], Varanasi upstream [S19], and Munger [S27]) due to improved hygienic conditions, but it increased subsequently at eight stretches (Haridwar [S8], Kanpur [S15], Raibareili [S16], Prayagraj [S17 and S18], Patna [S24], Berhampore [S30], and Serampore [S31]) due to improper defecation and mass bathing during 2007-2016. Dissolved oxygen level declined significantly, and biochemical oxygen demand increased (> 3 ppm), alarmingly at places receiving heavy untreated sewage water. The water quality of the Ganges was good up to Rishikesh, because of an undisrupted flow of the uncontaminated water from the higher altitudes (≥ 372 m) with higher forest cover, lower temperatures (< 21 °C), and higher dissolved oxygen (≥ 8.5 ppm) and due to the dissolution of antipathogenic chemical constituents of the medicinal herbs, pollutant degrading alkaline phosphatase, and bacteriophages. The present review is a systematic collection of data on river pollution, its scientific analyses, and its relationship with 6Ps (namely population, poverty, pollution, precipitation, plantation, and periodicity). Not only that, but the river water restoration measures have also suggested through the novel interlinked water working groups for implementing integrated water management strategies.


Assuntos
Monitoramento Ambiental/métodos , Recuperação e Remediação Ambiental/métodos , Rios/química , Esgotos/análise , Poluição da Água/análise , Qualidade da Água , Bactérias Gram-Negativas/isolamento & purificação , Índia , Oxigênio/análise
17.
Environ Monit Assess ; 191(9): 541, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31385054

RESUMO

Biophysical parameters affecting biomass carbon have been emphasized in the Paris Agreement for realizing climatic benefits from mitigation projects. The present study was conducted to assess the relation of biophysical parameters with forest biomass carbon in north Kashmir region of Himalayas. The relation of biomass carbon was assessed with (1) species type or strata including Cedrus deodara, mixed I (Cedrus deodara-Pinus wallichiana), mixed II (Abies pindrow-Picea smithiana) and Pinus wallichiana, (2) altitude (1292-2911 m amsl), (3) crown density, (4) aspect, (5) tree count or density and (6) location. Using a stratified sampling design, a total of 188 quadrats of 0.1 ha were laid across the entire region representing different biophysical parameters. Field observation including diameter at breast height and height were recorded and sample biomass (t ha-1) was estimated using volumetric equations. The observed relation of aboveground biomass carbon with species revealed a trend of mixed II ˃ Cedrus deodara ˃ mixed I ˃ Pinus wallichiana. A positive but weak correlation (R2 = 0.02) was found between aboveground biomass carbon and altitude. A reasonably good correlation (R2 = 0.40) was observed to exist between aboveground biomass carbon and crown density. The highest value of average biomass carbon (72.63 t ha-1) was recorded for the north-eastern aspect whereas the lowest value (44.60 t ha-1) was recorded for the eastern aspect. The aboveground biomass carbon and tree count was found positively correlated (+ 0.475, R2 = 0.48). Forest biomass carbon fluctuates within the same geographical region with a variety of biophysical factors. The growth rate of species, photosynthetic ability under different crown densities and climatic conditions could address the reasons for this variability. Biophysical relations of forest biomass carbon can be viewed as an important input for guidelines and policy matters on climate change.


Assuntos
Biomassa , Carbono/análise , Cedrus/crescimento & desenvolvimento , Mudança Climática/estatística & dados numéricos , Monitoramento Ambiental/métodos , Pinus/crescimento & desenvolvimento , Altitude , Florestas , Índia , Paquistão , Árvores/crescimento & desenvolvimento
18.
Environ Monit Assess ; 191(9): 543, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31388832

RESUMO

This study evaluates the impact of leachates from a municipal dumpsite on the quality of domestic water sources in the area for potable use. Concentrations of leachate-associated organic contaminants (such as diethyl-phthalate, total organic halogen (TOH); 2,4-dichlorophenol; nonylphenol-ethoxylate; methyl-ethyl-phthalate; borneol; total organic carbon (TOC); total Kjeldahl-nitrogen (TKN); ammonium-nitrogen (NH3-N); nitrate (NO3); nitrate-nitrogen (NO3-N); and total phosphorus (TP)) in rivers and groundwater in the Enugu Metropolis in southeastern Nigeria were assessed in this study. Results of laboratory analyses indicate that the average values of diethyl-phthalate, borneol, TOH, nonylphenol-ethoxylate and TOC are 0.08 mg/l, 0.04 mg/l, 1.05 mg/l, 0.2 mg/l and 1.64 mg/l, respectively for groundwater and 0.1 mg/l, 0.03 mg/l, 0.74 mg/l, 0.19 mg/l and 1.74 mg/l, respectively, for rivers. Three (diethyl-phthalate, borneol and TOH) out of these major five contaminants, in both rivers and groundwater, exceeded the maximum permissible limits, suggesting that the domestic water sources are marginally contaminated by the leachates. ANOVA test result suggests that the data sources were significantly variable, while principal component and correlation analyses identified TOH, 2,4-dichlorophenol, TKN, NO3, NO3-N, TP and borneol, which originated most probably from degradation of plastic materials and organic wastes in the dumpsite, as the priority contaminants. Consumption of domestic water sources within the dumpsite area, in untreated state, could lead to health risks as these priority organic contaminants are mostly carcinogenic, toxic and injurious to human systems.


Assuntos
Monitoramento Ambiental/métodos , Água Subterrânea/química , Rios/química , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água/análise , Compostos de Amônio/análise , Água Potável/química , Humanos , Nigéria , Nitratos/análise , Nitrogênio/análise , Ácidos Ftálicos/análise , Água/química
19.
Environ Monit Assess ; 191(9): 549, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31392440

RESUMO

Children are in direct contact with surface soil and may inadvertently ingest and inhale toxic contaminants while playing; hence, special attention should be given to playgrounds regarding toxic contaminants. The concentrations of ten toxic metals were determined in soil samples collected from school playgrounds and children's parks from the southwest region of Saudi Arabia. The soils were moderately alkaline (pH 7.6-8.8), the texture was dominated by sand particles (54-88%), and the organic matter was in the range of 2.06 to 4.82%. Analytical solutions were prepared by microwave-digestion using a HNO3/H2O2 mixture, and the concentrations of toxic elements were measured by inductively coupled plasma mass spectrometry (ICP-MS). Metal concentrations were recorded in the range of 0.014-0.087, 1.14-3.54, 0.85-23.29, 0.77-36.32, 312.6-2065.7, 285.3-822.6, 75.4-240.8, 0.00-53.12, 0.52-6.80, and 1.25-92.12 mg/kg dry soil for Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, and Zn, respectively. The levels of heavy metals in the studied playgrounds were below the permissible limits, indicating insignificant influence of anthropogenic activities and can be considered as unpolluted soil. Values of the enrichment coefficient (EC) and contamination factor (CF) were found to be less than one, suggesting that the source of these elements is mainly the local soil, with the exception of Ni and Zn in certain playgrounds (CF > 1), which indicates a possible contamination from external sources. The non-carcinogenic hazard index calculated for all of the metals was below one, indicating that the exposure to heavy metal through playground soil is unlikely to produce any adverse health effect in children playing in the playgrounds.


Assuntos
Exposição Ambiental/efeitos adversos , Metais Pesados/análise , Parques Recreativos , Poluentes do Solo/análise , Adolescente , Criança , Monitoramento Ambiental/métodos , Humanos , Peróxido de Hidrogênio/análise , Medição de Risco , Arábia Saudita , Instituições Acadêmicas , Solo/química
20.
Environ Monit Assess ; 191(9): 550, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31396767

RESUMO

A field experiment was conducted at Indian Council of Agricultural Research-National Rice Research Institute, Cuttack, Odisha, India in the dry seasons of 2015 and 2016 to assess the water vapor flux (FH2O) and its relationship with other climatic variables. The FH2O and climatic variables were measured by an eddy covariance system and a micrometeorological observatory. Daily mean FH2O during the dry seasons of 2015 and 2016 were 0.009-0.092 g m-2 s-1 and 0.014-0.101 g m-2 s-1, respectively. Seasonal average FH2O was 14.6% higher in 2016 than that in 2015. Diurnal variation for FH2O showed a bell-shaped curve with its peak at 13:30-14:00 Indian Standard Time (IST) in both the years. Carbon dioxide flux was found higher with rise in FH2O. This relationship was stronger at higher vapor pressure deficit (VPD) (20 ≤ VPD ≤ 40 and VPD > 40 hPa). The FH2O showed significant positive correlation with latent heat flux, net radiation flux, photosynthatically active radiation, air, water and soil temperatures, shortwave down and upwell radiations, maximum and minimum temperatures, evaporation, and relative humidity in both the years. Principal component analysis showed that FH2O was very close to latent heat flux in both the years (Pearson correlation coefficient close to 1). The two-dimensional observation map of the principal component F1 and F2 showed the observations taken during the vegetative stage and panicle initiation stage, and flowering stage and maturity stage were closer to each other. It can be concluded that the most important climatic variables controlling the FH2O were latent heat of vaporization, net radiation, air temperature, soil temperatures, and water temperature.


Assuntos
Ciclo do Carbono/fisiologia , Monitoramento Ambiental/métodos , Oryza/química , Vapor/análise , Agricultura , Dióxido de Carbono/análise , Ecossistema , Índia , Análise de Componente Principal , Estações do Ano , Solo/química , Temperatura Ambiente , Água/química
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