Spatial-temporal assessment of pollutions in Ekbatan lake using qualitative indices and statistical methods Abstract The purpose of this study was to use water quality indices and statistical methods based on physicochemical parameters for spatial-temporal assessment of Ekbatan lake pollution. Sampling stations were selected based on systematic, non-random approach, and it was performed in 7 stations, with intervals of 30 days in 2010–2011. At first, indices model of IRWQI, NSFWQI, and TLI was prepared in GIS environment based on qualitative parameters by interpolation functions (deterministic and geostatistical methods). Results demonstrated that qualitative parameters of FC, NO3−, BOD5, DOSat%, pH, PO43− and Turb respectively with annual average quality of 13.5 very bad, 27.4 bad, 46.8, 47.2 and 48.6 moderate, 70 goodish, and 71 good using statistical and geostatistical methods—accounted for highest pollution level and created greatest impact on lake pollution status. This amount was considered as bad and eutrophication quality on the southern and east margins of the lake because of the effluent load of the rivers under high land use activities (especially residential and then agricultural) in comparison with the lake core and north (showing baddish and moderate quality status) has more pollution level than that. Also, all parameters showed a high positive correlation and significance with increased of water temperature owing to increase in pollutant land use activities and condensation of pollutants and decreased of floodrains in warm seasons, and two parameters of TDS and Turb show high significance rather than beginning floodrains in spring and autumn. Also, lake was in qualitative status of baddish 43.7, moderate 58.2, and mild eutrophication 57.2 based on IRWQI, NSFWQI, and TLIChl.a respectively. Further, according to IRWQI index, the quality of lake in summer was in baddish status of 35, in half of initial winter in goodish condition of 56 and spring and autumn in moderate qualitative status of 46.

Determination of antimony and barium in UK air quality samples as indicators of non-exhaust traffic emissions Abstract The aim of this study was to determine concentrations of antimony and barium in air quality samples and assess the potential suitability of these metals as tracer elements for non-exhaust traffic emissions sources. Air quality filters sampled at monitoring sites around the UK for the purposes of the UK Heavy Metals Monitoring Network were subjected to microwave digestion in hydrogen peroxide and nitric acid, then analysed by ICP-MS for a suite of metals including antimony and barium. The average antimony concentration found across all the network sites was 1.84 ng m−3; the average barium concentration was 6.33 ng m−3. The range of antimony concentrations observed was 0.13–8.02 ng m−3; barium concentrations ranged from levels below the detection limit of 0.18 to 39.9 ng m−3. There are no legislative limits for antimony and barium in ambient air, but the maximum concentrations found are well below the Workplace Exposure Limits specified by the UK Health and Safety Executive. The highest concentrations were found at roadside sites situated to monitor traffic environments, supporting the suitability of antimony and barium to be considered tracer elements for traffic emissions sources. Strong correlations were observed between antimony, barium and copper, indicating they share a common traffic-related source. Based on the strong correlation with copper at urban and traffic locations, indicative annual UK atmospheric emission estimates for antimony and barium in brake and tyre wear were calculated as 6 and 19 tonnes respectively.

Toxic heavy metal (Pb and Cd) content in tobacco cigarette brands in Selangor state, Peninsular Malaysia Abstract Cadmium (Cd) and lead (Pb) are ubiquitous metals widely distributed in the environment, resulting in toxic health effects. This project aims to evaluate Pb and Cd as toxic elements in 15 different tobacco cigarette brands produced and/or sold in Selangor state, Peninsular Malaysia. The concentrations of Pb and Cd in all tobacco brands tested in this study were determined using the air-acetylene flame atomic absorption spectrophotometer (AAS). On average, the concentrations of Pb and Cd in different tobacco brand samples ranged from 3.05 and 0.80 μg/g dw, respectively. The results indicate that assessment mean values of Pb inhaled from smoking one packet of 20 cigarettes were in the range of 1.55–3.51 μg. Furthermore, the concentration of Cd inhaled per packet of cigarettes (20 sticks) is estimated to be 0.04–0.36 μg. However, there was a significant difference in the concentrations of Pb and Cd between the different brands of tobacco cigarettes, among cigarette prices (cheap versus expensive) of tobacco brands. In conclusion, cigarette smokers in Selangor, Malaysia, are heavily exposed to Pb and Cd, and such exposure could adversely affect their health in the long term. The impact of toxic heavy metals on smokers in this state would be an area for future research.

Light microscopic studies to evaluate fish scales as non-invasive indicators of heavy metal–contaminated waters Abstract Heavy metal pollution in aquatic bodies is a matter of serious concern for aquatic fauna and human health. This study evaluated the effect of heavy metals on structural aberrations in fish scales of freshwater Indian major carp Labeo rohita. Scales from two size groups—lesser than and equal to 40 cm and greater than 40 cm—collected from three markets of Ludhiana district for a period of 6 months were assessed. The values of Pb, Zn and Cr in fish scales exceeded the permissible limits. Structural alterations such as distorted focus, damaged and eroded circuli, distorted pattern of circuli, damaged margins of scales, dispersed chromatophores, disorganised radii and damaged tubercles were observed on the dorsal surface of scales using light microscopy. It is postulated that heavy metals would be responsible for structural anomalies on scales as their accumulation was higher in larger fishes which have been exposed to metals for longer duration. These observations clearly suggest that fish scales are effective non-invasive indicator of water quality where fish have been reared and cultured.

Potential of urban trees for mitigating heavy metal pollution in the city of Novi Sad, Serbia Abstract The current study analyzed heavy metal (HM) concentrations in the urban soil and tree leaves in the city of Novi Sad, Serbia, with the aim to identify specific tree species with good HM bioaccumulative abilities that can mitigate HM pollution in urban areas. Zinc (Zn), copper (Cu) and lead (Pb) were selected for the analysis of tree leaves and soil at 16 locations close to urban roads, main boulevards and high-traffic streets. Leaf material of four most common tree species: Platanus × acerifolia (Aiton) Willd., Celtis occidentalis L., Tilia argentea L. and Quercus robur L. and soil samples were analyzed with the aim to identify the potential hotspots and sources of pollution. Analysis of variance (ANOVA) and t test was applied to the available data sets to find differences between the HM concentrations in the analyzed trees and soil samples. Geographic information system (GIS) mapping was used for visualization of the concentration distributions and illustration of the HM contaminated hotspots. Bioconcentration factors (BCF) were calculated and they showed that the plants of the species Celtis occidentalis L. have the ability to retain Cu, the species Quercus robur L. retains mostly Zn, Tilia argentea L. accumulates Pb, while Platanus x acerifolia (Aiton) Willd. retains the smallest amount of the tested HMs.

Dynamics of dissolved greenhouse gas response to seasonal water mixing in subtropical reservoirs Abstract Although indispensable, significant uncertainty still exists in the underlying processes of the formation, dynamics, and emission of greenhouse gases (GHGs), the critical elements needed for the accurate estimation of greenhouse gas fluxes in inland lakes and reservoirs. Seasonal changes in water thermal stratification and turbulence strongly influence the concentration and emission of dissolved GHGs in water columns. Here, we studied the stratification and overturn processes of water column in the subtropical Lianhe Reservoir during different seasons and determined the dynamics of dissolved CO2, CH4, and N2O in the reservoir. Observation of temperature and analysis of chlorofluorocarbons (CFCs) clearly suggested that stratification of water column occurred in summer, but not in winter. The results showed that while dissolved oxygen (DO) was high in the top 5-m layer (the upper epilimnion layer), it dropped considerably especially below 10 m, resulting in an increase in concentration of CO2 and CH4. The high concentrations of dissolved N2O and CH4 were related to the decomposition of organic matter in the hypolimnion layer under anaerobic conditions after stratification. In winter overturn period, vertical circulants of water not only homogenized the concentration of DO in the water column, but also potentially moved CO2, CH4, and N2O from the bottom to the surface of the reservoir. The estimated GHG flux from the reservoir was − 7.13 mmol m−2 day−1 in summer and 2.14 mmol m−2 day−1 in winter. There was the potential that CO2 fluxes from subtropical lakes and reservoirs are overestimated by traditional geochemical models.

Spatial and temporal variation of the vegetation of the semiarid Puna in a pastoral system in the Pozuelos Biosphere Reserve Abstract This study aimed to analyze the spatial and temporal variation of the vegetation in the northern Argentine Puna, utilizing both field sampling and remote-sensing tools. The study was performed within the Pozuelos Biosphere Reserve (Jujuy province, Argentina), which aims to generate socio-economic development compatible with biodiversity conservation. Our study was designed to analyze the dynamics of the Puna vegetation at local scale and assess and monitor the seasonal (dry and wet seasons), interannual, and spatial variation of the vegetation cover, biomass, dominant species, and vegetation indices. Ten vegetation units (with differences in composition, cover, and high and low stratum biomass) were identified at our study site. The diversity of these vegetation units correlated with geomorphology and soil type. In the dry season, the vegetation unit with greatest vegetation cover and biomass was the Festuca chrysophylla grassland, whereas in the wet season, the units with greatest cover and biomass were vegas (peatlands) and short grasslands. The Festuca chrysophylla grasslands and short grasslands were located in areas with clay soils, except peatlands, associated with valleys and coarse-texture soils. The vegetation indices used (NDVI, SAVI, and MSAVI2) were able to differentiate functional types of vegetation and showed a good statistical fit with cover values. Our results suggest that the integrated utilization of remote-sensing tools and field surveys improves the assessment of the Puna vegetation and would allow a periodic monitoring at production unit scale taking into account its spatial and temporal variation.

Effect of soil pH and organic matter content on heavy metals availability in maize ( Zea mays L.) rhizospheric soil of non-ferrous metals smelting area Abstract Maize plant tissues and rhizosphere soil were collected from an agricultural area around the Huludao Zinc Plant in Liaoning Province, China, to investigate the effects of soil pH and organic matter content on heavy metal concentration and accumulation in different types of maize tissues. The mean pH of the soil samples was 7.02 (range 5.74–7.86), and the mean organic matter content was 31.03 g kg−1 (range 18.80–52.20 g kg−1). The average Cu, Zn, Pb, and Cd contents in soil were 2.92, 6.72, 7.95, and 16.28 times greater than the corresponding background values, respectively. The geo-accumulation index indicated that the soils were uncontaminated to moderately contaminated by Cu, moderately to strongly contaminated by Pb and Zn, and strongly contaminated by Cd. The average available Cu, Pb, Zn, and Cd contents in the soil samples were 16.34, 6.997, 69.77, and 0.190 mg kg−1, respectively, while their bioavailability coefficients were 28.53%, 1.65%, 40.44%, and 10.83%, respectively. The respective mean Pb and Cd concentrations in grain samples were 0.341 and 0.342 mg kg−1, which exceeded the maximum concentrations permitted by the Chinese National Standard. Thus, the maize grain is not safe for consumption and poses potential risks to human health. With the exception of Cu, the combined effect of pH and organic matter content had a stronger influence on the availability of heavy metals in soil compared with either factor alone. Cd uptake in maize plant tissues was affected by the combination of soil pH, organic matter content, and bioavailable Cd content in soil; however, the combination of these three factors had only slight effects on Cu, Zn, and Pb absorption in maize tissues.

Relations of dissolved-oxygen variability, selected field constituents, and metabolism estimates to land use and nutrients in high-gradient Boston Mountain streams, Arkansas Abstract Continuous monitoring data can be extremely useful for assessing water-quality conditions particularly for variables, such as dissolved oxygen, that exhibit dynamic diel swings. As a means of evaluating stream dissolved oxygen criteria used by the Arkansas Department of Environmental Quality (ADEQ), we compared continuous dissolved oxygen (DO) data collected at five small- to moderate-sized (watersheds 10–100 mi2), high-gradient streams in the Boston Mountains distributed across a land-use and nutrient condition gradient. The sampled streams exhibit a general pattern established for other aquatic systems (e.g., larger streams, low-gradient streams, and lakes) where increasing land-use intensity results in increased nutrient concentrations, stream eutrophication, and increased DO variability. DO concentrations were < 6 mg/L for fewer than 4% of measurements at the two sites identified “a priori” as least disturbed by nutrient and land-use indices, while concentrations at the three sites identified as moderately and most disturbed were < 6 mg/L for 20 to 33% of measurements. These findings demonstrate that the current criterion (10% of the DO measurements are < 6 mg/L) employed by ADEQ was effective at identifying various degrees of DO impairment in Boston Mountain streams. Our analysis also demonstrated that continuous pH and specific conductance data and estimates of stream metabolism were helpful for attributing DO variability to anthropogenic or natural origins. Considerations that were useful for examining these relationships and evaluating ADEQ’s DO criterion should be applicable to DO studies in other locations where stream and geologic characteristics are similar to those of the Boston Mountains.

Development and application of a low-cost rapid assessment system for coastal benthic habitats Abstract Information on community structure and spatial distribution of benthic habitats are important in marine conservation and management. Coral areas, often monitored by trained scuba divers, are of importance for the ecosystem goods and services they provide. The data gathered may, however, be limited due to cost and time constraints. These restrictions and the continuing decline in coral reef health contribute to the need to develop rapid methods to efficiently document the distribution and status of coral reefs. A Rapid Assessment Instrument for Coastal Benthic Habitats (ARAICoBeH) System was developed to enable large-scale but low-cost coastal benthic habitat characterization and mapping without compromising accuracy. Inquiries on community structure and status in coral-dominated areas are also possible with the data collected using the method. The instrument, as well as the data processing and mapping algorithm are described in detail in this paper. A comparative study was conducted between ARAICoBeH and the frequently used underwater photo transect method. Variables compared were percent coral cover, functional group diversity, community structure as well as time and monetary requirements. There were no significant differences in estimates of percent coral cover and diversity of benthic functional groups for majority of sites while estimates of community structure were very similar. ARAICoBeH is cheaper and requires less time to gather the same amount of data as that of the photo transect method. The spatial distribution of coastal benthic habitats and community structure of coral-dominated areas in El Nido, Palawan, Philippines, are included to illustrate the application of the method.