Lead isotope ratios in lichen samples evaluated by ICP-ToF-MS to assess possible atmospheric pollution sources in Havana,Cuba

Epiphytic lichens, collected from 119 sampling sites grown over “Roistonea Royal Palm” trees, were used to assess the spatial distribution pattern of lead (Pb) and identify possible pollution sources in Havana (Cuba). Lead concentrations in lichens and topsoils were determined by flame atomic absorption spectrophotometry and inductively coupled plasma (ICP) atomic emission spectrometry, respectively, while Pb in crude oils and gasoline samples were measured by ICP-time of flight mass spectrometry (ICP-ToF-MS). Lead isotopic ratios measurements for lichens, soils, and crude oils were obtained by ICP-ToF-MS. We found that enrichment factors (EF) reflected a moderate contamination for 71% of the samples (EF > 10). The ²⁰⁶Pb/²⁰⁷Pb ratio values for lichens ranged from 1.17 to 1.20 and were a mixture of natural radiogenic and industrial activities (e.g., crude oils and fire plants). The low concentration of Pb found in gasoline (<7.0 μg L^?1) confirms the official statement that leaded gasoline is no longer used in Cuba.     

Photobiology of corals from Brazil’s near-shore marginal reefs of Abrolhos

Coral communities were examined from highly turbid near-shore marginal reefs of Abrolhos (Brazil) to test a paradigm previously developed from observations in clear water reefs; specifically, that coral photobiological properties follow a highly conserved linear relationship with optical depth (ζ) via preferential ‘non-photochemical’ over ‘photochemical’ dissipation of absorbed light energy. PAM flourometry in situ was used to examine the photobiology of the most dominant coral species throughout the platform surfaces and bases of Abrolhos’ characteristic ‘chapeir?es’ reef framework; however, none of the species consistently adhered to the ‘clear water paradigm’. PAM measurements further demonstrated that species conformed to two different strategies of non-photochemical energy dissipation: transient but relatively rapid for the two closely related endemic species (Mussismilia braziliensis and Mussismilia harttii) as opposed to more persistent for Montastrea cavernosa, Porites astreoides and Siderastrea stellata. Further experiments demonstrated that tolerance to anomalous stress amongst species did not correspond with the non-photochemical energy dissipation strategy present but was consistent with the relative dominance of species within the chapeir?es coral communities.     

Accumulation of heavy metals in native Andean plants: potential tools for soil phytoremediation in Ancash (Peru)

Metal contamination is a recurring problem in Peru, caused mainly by mine tailings from a past active mining activity. The Ancash region has the largest number of environmental liabilities, which mobilizes high levels of metals and acid drainages into soils and freshwater sources, posing a standing risk on human and environmental health. Native plant species spontaneously growing on naturally acidified soils and acid mine tailings show a unique tolerance to high metal concentrations and are thus potential candidates for soil phytoremediation. However, little is known about their propagation capacity and metal accumulation under controlled conditions. In this study, we aimed at characterizing nine native plant species, previously identified as potential hyperaccumulators, from areas impacted by mine tailings in the Ancash region. Plants were grown on mine soils under greenhouse conditions during 5 months, after which the concentration of Cd, Cu, Ni, Pb, and Zn was analyzed in roots, shoots, and soils. The bioaccumulation (BAF) and translocation factor (TF) were calculated to determine the amount of each metal accumulated in the roots and shoots and to identify which species could be better suited for phytoremediation purposes. Soil samples contained high Cd (6.50–49.80 mg/kg), Cu (159.50–1187.00 mg/kg), Ni (3.50–8.70 mg/kg), Pb (1707.00–4243.00 mg/kg), and Zn (909.00–7100.00 mg/kg) concentrations exceeding national environmental quality standards. After exposure to mine tailings, concentrations of metals in shoots were highest in Werneria nubigena (Cd, 16.68 mg/kg; Cu, 41.36 mg/kg; Ni, 26.85 mg/kg; Zn, 1691.03 mg/kg), Pennisetum clandestinum (Pb, 236.86 mg/kg), and Medicago lupulina (Zn, 1078.10 mg/kg). Metal concentrations in the roots were highest in Juncus bufonius (Cd, 34.34 mg/kg; Cu, 251.07 mg/kg; Ni, 6.60 mg/kg; Pb, 718.44 mg/kg) and M. lupulina (Zn, 2415.73 mg/kg). The greatest BAF was calculated for W. nubigena (Cd, 1.92; Cu, 1.20; Ni, 6.50; Zn, 3.50) and J. bufonius (Ni, 3.02; Zn, 1.30); BCF for Calamagrostis recta (Cd, 1.09; Cu, 1.80; Ni, 1.09), J. bufonius (Cd, 3.91; Cu, 1.79; Ni, 18.36), and Achyrocline alata (Ni, 137; Zn, 1.85); and TF for W. nubigena (Cd, 2.36; Cu, 1.70; Ni, 2.42; Pb, 1.17; Zn, 1.43), A. alata (Cd, 1.14; Pb, 1.94), J. bufonius (Ni, 2.72; Zn, 1.63), and P. clandestinum (Zn, 1.14). Our results suggest that these plant species have a great potential for soil phytoremediation, given their capability to accumulate and transfer metals and their tolerance to highly metal-polluted environments in the Andean region.     

Year-long continuous personal exposure to PM2.5 recorded by a fast responding portable nephelometer

Personal exposure to particulate matter of aerodynamic diameter under 2.5 μm (PM_2.5) was monitored using a DustTrak nephelometer. The battery-operated unit, worn by an adult individual for a period of approximately one year, logged integrated average PM_2.5 concentrations over 5 min intervals. A detailed time-activity diary was used to record the experimental subject’s movement and the microenvironments visited. Altogether 239 days covering all the months (except April) were available for the analysis. In total, 60 463 acceptable 5-min averages were obtained. The dataset was divided into 7 indoor and 4 outdoor microenvironments. Of the total time, 84% was spent indoors, 10.9% outdoors and 5.1% in transport. The indoor 5-min PM_2.5 average was higher (55.7 μg m^?3) than the outdoor value (49.8 μg m^?3). The highest 5-min PM_2.5 average concentration was detected in restaurant microenvironments (1103 μg m^?3), the second highest 5-min average concentration was recorded in indoor spaces heated by stoves burning solid fuels (420 μg m^?3). The lowest 5-min mean aerosol concentrations were detected outdoors in rural/natural environments (25 μg m^?3) and indoors at the monitored person’s home (36 μg m^?3). Outdoor and indoor concentrations of PM_2.5 measured by the nephelometer at home and during movement in the vicinity of the experimental subject’s home were compared with those of the nearest fixed-site monitor of the national air quality monitoring network. The high correlation coefficient (0.78) between the personal and fixed-site monitor aerosol concentrations suggested that fixed-site monitor data can be used as proxies for personal exposure in residential and some other microenvironments. Collocated measurements with a reference method (β-attenuation) showed a non-linear systematic bias of the light-scattering method, limiting the use of direct concentration readings for exact exposure analysis.     

A Simplified Dynamic Model for the Activated Sludge Process with High Strength Wastewaters

A simplified dynamic model for the activated sludge process with high-strength wastewaters is presented. The model is based on activated sludge models and predicts effluent chemical oxygen demand concentration using only four parameters. Experimental data for testing the model were obtained in an activated sludge plant using flax retting wastewater. The proposal of the model is described: mass balance to the system, selection of variables and behaviour of the theoretical values versus experimental results.     

Post-breeding migration in male great bustards: low tolerance of the heaviest Palaearctic bird to summer heat

Radio tracking of 142 males captured at 44 leks in Spain showed that partial migration of great bustard males in summer is a widespread behaviour in many Iberian populations, in contrast to their previously assumed sedentariness. A variable number of males migrated immediately after mating to summering areas with lower temperatures and human population densities and more trees and rainfall levels than the breeding sites. Birds selected there fields with trees and sunflower crops which provided shade during the hottest midday hours and protective cover against predators. Males breeding in areas with higher July temperatures had a higher tendency to migrate, and males from hotter, southern regions migrated longer distances than those from milder, northern regions and showed a preferred northward direction. These results confirmed various predictions from the weather sensitivity hypothesis, suggesting that summer migration of great bustard males represents primarily an adaptation to escape the summer heat of most breeding areas in central and southern Iberia. The hypothesis that males migrated to benefit from higher food availability at the summering areas could not be rejected by our results. Finally, migrating males also gained more tranquillity during the post-breeding moult due to the lower human population density at the summering areas. Summer migration of Iberian great bustard males may thus be interpreted as a form of behavioural thermoregulation which has not been described for other Palaearctic populations of this species or for other bird species breeding in temperate latitudes.     

Additional disturbances as a beneficial tool for restoration of post-mining sites: a multi-taxa approach

Open interior sands represent a highly threatened habitat in Europe. In recent times, their associated organisms have often found secondary refuges outside their natural habitats, mainly in sand pits. We investigated the effects of different restoration approaches, i.e. spontaneous succession without additional disturbances, spontaneous succession with additional disturbances caused by recreational activities, and forestry reclamation, on the diversity and conservation values of spiders, beetles, flies, bees and wasps, orthopterans and vascular plants in a large sand pit in the Czech Republic, Central Europe. Out of 406 species recorded in total, 112 were classified as open sand specialists and 71 as threatened. The sites restored through spontaneous succession with additional disturbances hosted the largest proportion of open sand specialists and threatened species. The forestry reclamations, in contrast, hosted few such species. The sites with spontaneous succession without disturbances represent a transition between these two approaches. While restoration through spontaneous succession favours biodiversity in contrast to forestry reclamation, additional disturbances are necessary to maintain early successional habitats essential for threatened species and open sand specialists. Therefore, recreational activities seem to be an economically efficient restoration tool that will also benefit biodiversity in sand pits.     

Wind energy in the Isthmus of Tehuantepec: conflicts and social implications

Social acceptance is fundamental, and directly affects the installation of wind farms. In this paper, the factors that have had the greatest influence on the development of wind energy in the Itsmo region of Tehuantepec, Mexico are identified. The data were collected face to face through a semi-structured questionnaire of 31 people: owners, municipal authorities, opposition groups, and academic members. The results of the interview highlight the social impact, the lack of application, and concerning ILO Convention 169, the abuse of community rights. As a result, people interviewed perceive that the environmental impact of the installation, and operation of wind farms has been ambivalent: positive due to the intrinsic benefits that wind energy generates compared to other energy sources, and negative in terms of affectation by the noise, and the landscape. However, the income received by the owners of land in which wind facilities are located is lower compared to other parts of the world. In general, the facts show a disintegration between the authorities (federal, state, and municipal), universities are isolated from wind projects, communities are not consulted in projects, and large companies are the main beneficiaries.

     

Using electrical resistivity tomography to assess the effectiveness of managed aquifer recharge in a salinized coastal aquifer

Over 40 years, the detrital aquifer of the Plana de Castellón (Spanish Mediterranean coast) has been subjected to seawater intrusion because of long dry periods combined with intensive groundwater exploitation. Against this backdrop, a managed artificial recharge (MAR) scheme was implemented to improve the groundwater quality. The large difference between the electrical conductivity (EC) of the ambient groundwater (brackish water due to marine intrusion) and the recharge water (freshwater) meant that there was a strong contrast between the resistivities of the brackish water saturated zone and the freshwater saturated zone. Electrical resistivity tomography (ERT) can be used for surveying similar settings to evaluate the effectiveness of artificial recharge schemes. By integrating geophysical data with lithological information, EC logs from boreholes, and hydrochemical data, we can interpret electrical resistivity (ER) with groundwater EC values and so identify freshwater saturated zones. Using this approach, ERT images provided a high-resolution spatial characterization and an accurate picture of the shape and extent of the recharge plume of the MAR site. After 5 months of injection, a freshwater plume with an EC of 400–600 μS/cm had formed that extended 400 m in the W-E direction, 250 m in the N-S direction, and to a depth of 40 m below piezometric level. This study also provides correlations between ER values with different lithologies and groundwater EC values that can be used to support other studies.     

Why are Prices in Wild Catch and Aquaculture Industries so Different?

Through a comparative analysis of prices in capture fisheries and aquaculture sectors, the objectives of this paper are a) to investigate three the trends in prices of forage catches to feed the aquaculture species, b) to analyze the amount of fish species need to feed aquaculture species in order to assess the level of efficiency in resource use, and c) to examine the degree of economic concentration either in wild-catch industry and aquaculture sectors. The results show that prices of cultivated species are higher than prices of the same species when harvested from the sea. We explain this fact by the interplay of three forces. First, the amount of wild fish to feed aquaculture species continues to improve over time. Second, the pressure of fishing activities has not been reduced since catches of most forage fishes are declining, which induce higher prices of capture species that feed aquaculture production. Third, the level of seafood market concentration is significantly higher in aquaculture than in wild catches, which generates higher prices in aquaculture.