Yeasts recovered in tannery wastes: candidates for decontamination?

Field and laboratory investigations were carried out in Fès, Morocco to identify yeasts growing in river waters contaminated with tannery wastes and to determine if one or several yeast species are possible candidates to remove chromium and polyphenols present in such wastes. Samples of river water were collected from 22 sites contaminated with tannery wastes and four sites not polluted with tannery wastes. Fifteen yeast species were identified in the sites polluted with tannery wastes and Debaryomyces hansenii was the major species. High values of electrical conductivity, inorganic and organic matter in suspension, salinity, ammonium ions, chlorides, chromium, nitrates, sulphates and polyphenols were found in waters collected from these sites. By contrast, in the four sites not polluted with tannery wastes, 14 yeast species were identified and five belonged to the Candida genus. D. hansenii was not recovered in these last sites. Because of its high frequency in waters polluted with tannery wastes, the ability of D. hansenii to remove the main polluting agents (chromium and/or polyphenols) from tannery wastes in a Mediterranean climate should be tested.     

Hepatic elemental contents and antioxidant enzyme activities in Algerian mice (Mus spretus) inhabiting a mine area in central Portugal

In this study the effects of heavy metals (manganese, iron, copper, zinc) and selenium exposure on the hepatic activity of antioxidant enzymes, superoxide dismutase (SOD) and glutathione S-transferases (GST), were appraised on a seasonal basis in Algerian mice (Mus spretus) inhabiting an active copper mine area. A reference population of the same species was considered for comparative purposes. Different patterns of seasonal variation were found in both populations for the manganese, iron and selenium hepatic concentrations and SOD activity. When the two populations were compared, iron and selenium concentrations were enhanced in mice from the polluted area. In addition, SOD activity was significantly decreased in summer in exposed mice, but no other significant changes in SOD and GST activities between sites throughout the year were recorded. However, when seasonal data within each group of mice were pooled, significant differences were found between sites for the average concentrations of manganese, iron and selenium, which are higher in the polluted site. In addition, significant differences were obtained for the average values of SOD and of GST activities, due to simultaneously higher GST values and slightly lower SOD values in the polluted site. The population from the reference site was more homogeneous for all parameters measured than the population from the polluted area. These results, in particular the higher variability in data collected from mice exposed to heavy metals and selenium, combined with the negative associations between biochemical markers and heavy metals, may suggest, despite the good adaptability of the mice to their habitat, biochemical stress due to diminished environmental quality.     

Multi-biochemical responses of benthic macroinvertebrate species as a complementary tool to diagnose the cause of community impairment in polluted rivers

Biological indexes, based on benthic macroinvertebrate taxa, are currently used worldwide to measure river ecological quality. These indexes assign a global ecological status of the biotic community, but not necessarily may detect specific effects of water pollutants. Conversely a large set of biochemical markers measured in macroinvertebrate benthic species can detect sublethal effects and inform us about additional environmental factors that are impairing benthic communities. This is especially interesting in moderately polluted sites, where other stressors are already affecting communities but not too strongly to be detected by biotic indexes. Up to ten different markers belonging to distinct metabolic paths and 42 contaminants measured in sample collections of the caddis fly Hydropsyche exocellata were assessed across a polluted gradient in the industrialized Mediterranean River basins of Besós and Llobregat (NE, Spain). Twenty four sample collections were selected to include macroinvertebrate communities representing the five impairment degrees defined by the Spanish Environmental authorities using the biotic metrics. Results evidenced a clear deterioration of the ecological water quality parameters and benthic communities towards downstream reaches. Biochemical responses varied significantly across the studied samples and were able to differentiate samples within communities having a good and deteriorated ecological stage. Principal Component Analyses indicated that salinity was one of the major stresses affecting macroinvertebrate assemblages, whereas antioxidant and metabolizing enzymes responded differently and were closely related to high and presumably toxic levels of accumulated organic pollutants. Therefore these results indicate that the use of multiple -markers sensitive to water pollution may provide complementary information to diagnose environmental factors that are impairing macroinvertebrate communities.     

Determination of anthropogenic and biogenic compounds on atmospheric aerosol collected in urban, biomass burning and forest areas in São Paulo, Brazil

This study was conducted at three sites of different characteristics in São Paulo State: São Paulo (SPA), Piracicaba (PRB) and Mata Atlântica Forest (MAT). PM₁₀, n-alkanes, pristane and phytane, PAHs, water-soluble ions and biomass burning tracers like levoglucosan and retene, were determined in quartz fiber filters. Samplings occurred on May 8th to August 8th, 2007 at the MAT site; on August 15th to 29th in 2007 and November 10th to 29th in 2008 at the PRB site and, March 13th to April 4th in 2007 and August 7th to 29th in 2008 at the SPA site.Aliphatic compounds emitted biogenically were less abundant at the urban sites than at the forest site, and its distribution showed the influence of tropical vascular plants. Air mass transport from biomass burning regions is likely to impact the sites with specific molecular markers.The concentrations of all species were variable and dependent of seasonal changes. In the most dry and polluted seasons, n-alkane and cation total concentrations were similar between the megacity and the biomass burning site. PAHs and inorganic ion abundances were higher at São Paulo than Piracicaba, yet, the site influenced by biomass burning seems to be the most impacted by the organic anion abundance in the atmosphere. Pristane and phytane confirm the contamination by petroleum residues at urban sites; at the MAT site, biological activity and long range transport of pollutants might influence the levels of pristane.     

Intense winter atmospheric pollution episodes affecting the Western Mediterranean

The geographic location of the Western Mediterranean Basin and its peculiar topography, the climatic conditions and the intense anthropogenic and natural emissions of atmospheric pollutants are key factors necessary to interpret the atmospheric aerosol phenomenology over this area. During the cold season it is common to have severe atmospheric particulate matter (PM) pollution episodes (of an anthropogenic origin) affecting this region, not only in the urban and industrial areas but also in the regional and rural sites. During these episodes, the midday hourly PM₁ levels at regional background sites are in many cases higher than those at urban areas. Around 10% of the days under winter anticyclonic conditions registered similar PM₁ levels at the regional background than at the urban area and, sporadically the daily PM₁ levels at the regional background sites may exceed those at urban sites. Furthermore, the very high hourly PM₁ levels measured at regional background sites during these episodes are not regularly attained in the closest urban areas, which leads to the hypothesis that an important formation of secondary aerosols occurs during the transport of the polluted air masses towards the elevated rural sites.The interpretation of the variability of PM levels and composition (2002-2008) at one urban site (Barcelona) and at one regional background site (Montseny) allows us to illustrate the phenomenology of these scenarios, to quantify the mean annual contributions to the PM levels and to identify their main tracers. Ammonium nitrate appears to be the most abundant compound during these scenarios, although organic species and trace metals also increase markedly. Owing to the intensity, composition and recurrence of these atmospheric pollution episodes, important health, climatic and ecological implications may be derived.     

Establishing physico-chemical reference conditions in Mediterranean streams according to the European Water Framework Directive

Type-specific physico-chemical reference conditions are required for the assessment of ecological status in the Water Framework Directive context, similarly to the biological and hydro-morphological elements. This directive emphasises that natural variability of quality elements in high status (reference condition) needs to be quantified. Mediterranean streams often present a marked seasonal pattern in hydrological, biological and geochemical processes which could affect physico-chemical reference conditions. This study establishes general physico-chemical reference conditions (oxygenation, nutrient, salinity and acidification conditions) for different Mediterranean stream types. 116 potential reference sites located in 23 Mediterranean catchments in Spain were sampled in spring, summer and autumn in 2003. All sites were subjected to a screening method for the selection of reference sites in Mediterranean streams (Mediterranean Reference Criteria) and classified using a pre-established stream typology that establishes five different stream types (temporary streams, evaporite-calcareous at medium altitude, siliceous headwaters, calcareous headwaters and large watercourses). Reference conditions (reference value and reference threshold equivalents to high-good class boundary) were calculated using two different methods according to the availability of reference sites: the reference site 75th percentile approach of all reference sites and the 25th percentile of the population approach. The majority of the studied potential reference sites (76 out of 116) were selected as reference sites. Regarding type-specific reference conditions, only siliceous headwaters could be considered different from the rest of stream types because lower conductivity and pH. All reference stream types presented seasonal differences as regards some parameters, except for temporary streams due to the high natural variation of this stream type. For those parameters which presented seasonal differences in a specific stream type, the least restrictive values were proposed as reference conditions.     

Letter to the editor

Fifty-one surficial sediment samples were collected from 21 stations situated in the nearshore area of the central Red Sea. Sediments were analysed for the major elements Ca, Mg, Al and Fe and the trace elements Mn, Cu, Zn, Ni, Cr, Co, Cd and Pb. The major grain-size classes gravel, sand and mud as well as organic carbon and carbonates were determined. Some samples were subjected to X-ray mineralogy. Sediments were generally coarse-grained but the fine fraction increased in the sheltered areas. The major mineralogical constituents of the sediments were carbonate minerals (calcite and aragonite) and detrital silicates (quartz and feldspars). Organic carbon was low (0.38%) in the northern part of the area but greatly increased in areas receiving direct sewage discharge (1-9.5%). Concentrations of trace elements were highly variable and appeared to be related to the grain size and the mineralogical composition. Generally, trace element concentrations were positively correlated with the mud and Al and Fe contents. In the polluted sites these regular associations were perturbed and trace elements were associated with organic matter. Element/Al ratios were used to group the sampling sites according to their degree of enrichment. The resulting order was different from that based on the absolute concentrations. The use of a combination of the element/Al ratio and the absolute concentration resulted in the distinction of highly and moderately contaminated and uncontaminated sites.     

Associations between shell strength, shell morphology and heavy metals in the land snail Cepaea nemoralis (Gastropoda, Helicidae)

In snails there is an intimate relation between shell size, thickness, strength and calcium content that may be influenced by environmental factors such as predation and heavy metal pollution. The snail Cepaea nemoralis shows variability for shell colour and banding pattern, and frequencies of colour morphs are highly variable in natural populations. We used C. nemoralis to investigate (i) the relations between shell morphology, shell Ca and heavy metal content (Cd, Cr, Pb, Zn), and shell strength, (ii) differences in shell morphology and shell strength among localities and yellow and pink shells and (iii) whether snails from polluted sites show increased levels of heavy metals in their shell. Larger shells were heavier, thicker, needed a higher force to be crushed but did not have a higher Ca concentration. Cd and Zn concentrations were higher in shells from polluted plots compared to shells from unpolluted plots but Ca levels in the shell were comparable among plots. Zn concentration was negatively correlated with shell traits. Although there was substantial variation in shell strength, thickness and dry weight among localities, none of the shell traits differed between individuals from polluted and reference plots nor between colour morphs. Our results suggest that the effect of heavy metal pollution on shell strength and morphology is limited in the investigated populations.     

Distribution of trace elements in organs of six species of cetaceans from the Ligurian Sea (Mediterranean), and the relationship with stable carbon and nitrogen ratios

Mercury (total and organic), cadmium, lead, copper, iron, manganese, selenium and zinc concentrations were measured in different organs of 6 different cetacean species stranded in an area of extraordinary ecological interest (Cetaceans' Sanctuary of the Mediterranean Sea) along the coast of the Ligurian Sea (North-West Mediterranean). Stable-isotopes ratios of carbon ((13)C/(12)C) and nitrogen ((15)N/(14)N) were also measured in the muscle. A significant relationship exists between (15)N/(14)N, mercury concentration and the trophic level. The distribution of essential and non-essential trace elements was studied on several organs, and a significant relationship between selenium and mercury, with a molar ratio close to 1, was found in the cetaceans' kidney, liver and spleen, regardless of their species. High selenium concentrations are generally associated with a low organic to total mercury ratio. While narrow ranges of concentrations were observed for essential elements in most organs, mercury and selenium concentrations are characterised by a wide range of variation. Bio-accumulation and bio-amplification processes in cetaceans can be better understood by comparing trace element concentrations with the stable-isotopes data.     

Impacts of pollution in feral Mya arenaria populations: The effects of clam bed distance from the shore

This study examined the relationships between population characteristics and the expression of physiological biomarkers of stress in an intertidal clam population under pollution at sites differing in thermal history and coastline distance. The clam population metrics were age distribution, growth, condition factor, distance of the clam beds from the shore, and gonad development. Physiological biomarkers comprised biomarkers of defence such as superoxide dismutase, labile IIb metals in tissues, redox status of metallothioneins and glutathione S-transferase, of tissue damage such as lipid peroxidation and DNA strand breaks, of reproduction as determined by vitellogenin-like proteins and gonadosomatic index and immunocompetence such as phagocytosis and hemocyte viability. Age-related pigments were also examined to compare the physiological age of the clams with their chronological age. The results showed that all the above biomarkers were significantly affected at one of the two polluted sites at least. Distance from the shore was significantly correlated with most (81%) of the biomarkers examined. Clams collected at one polluted site were physiologically older than clams from the corresponding reference site. Canonical and adaptive regression (artificial neural networks) analyses found that the biomarkers measured in this study were able to predict the ecologically relevant endpoints. Biomarkers implicated in defense mechanisms, tissue damage and age-related pigments were most closely related to the clam population characteristics. Sensitivity analysis of the learning algorithm found that the following physiological and biochemical markers were the most predictive, in decreasing order, of clam population characteristics: glutathione S-transferase, phagocytosis, age pigments, lipid peroxidation in the gills, labile IIb metals and total MT levels. These biomarkers were affected by the distance of the clam beds from the shore, site quality (pollution) and reproduction activity.     

Red Books for threatened Mediterranean landscapes as an innovative tool for holistic landscape conservation. Introduction to the western Crete Red Book case study

In view of the alarming threats to our planet Earth and its natural and cultural diversity, the IUCN World Conservation Organization must broaden the scale of its efforts from the species and ecosystem level to the landscape level. For this purpose new, more comprehensive strategies and powerfuls tools, based on holistic landscape planning and dynamic conservation management, are urgently needed. The Mediterranean Basin, presently undergoing an alarming process of biological, cultural and scenic degradation can serve as a good example for these needs. Here, as elsewhere, almost all conservation efforts have been devoted to the protection of restricted areas such as nature reserves or parks without much regard for the fate of the open landscape as a whole and the need for the conservation and restoration of its great natural and cultural assets. In order to gain greater public awareness and apprehension of these threats, to change the attitudes of politicians and decision-makers, and to provide practical guidance for holistic, sustainable and multibeneficial land use planning and management, a new tool of ‘Red Books for Threatened Landscapes’ is offered. These should present in clear non-technical terms, with ample maps and illustrations, recent, adverse biological, ecological, cultural and socio-economic changes in highly valuable and not yet irreversibly despoiled landscapes and their future threats, and suggest alternative, sustainable land use strategies with sounder conservation and restoration options. The Western Crete study, is the first Mediterranean Red Book case study, carried out by a multinational and multidisciplinary team. It will serve as an important example for a Red Book blueprint, to be prepared by the IALE-IUCN-CESP Working Group on Red Books for Threatened Landscapes.     

Antioxidant enzymes in brackishwater oyster, Saccostrea cucullata as potential biomarkers of polyaromatic hydrocarbon pollution in Hooghly Estuary (India): seasonality and its consequences.

Use of antioxidant enzymes as biomarkers often becomes a complicated process at application level because they show considerable seasonal fluctuation due to both natural and biological factors. In this study, we studied the consequences of seasonal variation of antioxidant enzymes [catalase (EC 1.11.1.6), superoxide dismutase (SOD, EC 1.15.1.1), glutathione peroxidase (GPX, EC 1.11.1.9) and microsomal NADPH-DT diaphorase (EC 1.6.99.2)] in the digestive gland of wild brackishwatcr oysters, Saccostrea cucullata for biomonitoring against polyaromatic hydrocarbon (PAH) contamination in Hooghly Estuary, north-eastern coast of India. As a general trend, maximum antioxidant enzyme activities were detected in pre-monsoon period or summer (March-June) followed by a gradual decrease during monsoon (July-October) with a minimum in post-monsoon period or winter (November-February) and this pattern was similar to tissue concentrations of PAHs also. The physiological fluctuations of the antioxidant defense systems were inversely-related to the lipid peroxidation indicating an enhanced susceptibility of oyster tissues to oxidative stress during post-monsoon or winter period. However, the oysters from polluted populations exhibited consistent very high PAHs load in their tissues as well as significant increases in the activities of antioxidant enzymes than in non-polluted populations in all three seasons. The results indicated that the antioxidant enzymes, catalase, SOD and microsomal NADPH-DT diaphorase in digestive gland of S. cucullata could be useful biomarkers of PAHs contamination. It also emphasized that seasonal variation of potential biomarkers like such enzymes should be incorporated into interpretation of biomonitoring studies by the use of appropriate controls and identical treatment in analysis of polluted and non-polluted samples.     

The effects of organic pollution on benthic organisms near Marseille

A quantitative survey of sublittoral marine organisms was carried out in polluted and unpolluted waters near Marseille (France). Samples from rocky substrates indicate that organic pollution effects have not decreased since earlier surveys.

Studies of beds of Posidonia oceanica, the dominant Mediterranean sea grass, show that its biomass is low in the polluted Gulf of Marseille compared with that in unpolluted bays near Marseille and with data from Malta. Crops were particularly low in shallow water to 15m where it is suggested that grazing by echinoids, whose numbers are probably encouraged by high levels of organic material, could be an important factor limiting growth, as well as other factors such as low underwater irradiance and detergent toxicity.

Along the most polluted coastline near the main sewer outlet at Cortiou, Posidonia was absent and is probably excluded by indirect and direct effects of the effluent. The decline of these sea grass beds has serious implications for sediment stability and the survival of associated biota.     

In situ tests for water quality assessment: a case study in Pampean rivers

Two invertebrate species (Hyalella curvispina and Palaemonetes argentinus) and one macrophyte (Egeria densa) from a naturally high nutrient content system (Pampean rivers of La Plata, Argentina) were evaluated for their potential use in situ assays aiming to assess changes in water quality. Invertebrates were individually placed in cylindrical chambers in polluted sections of rivers and in reference upstream sites. Mortality after 48 h was high in polluted and reduced in control sites. Mortality was also higher in situ assays than in laboratory static tests. Standard sections of the macrophyte were also deployed at the reference and control sites. Growth (7 days) in terms of mass increment (but not in length) was consistently reduced in polluted sites. Results of benthic invertebrate and periphitic algae surveys were consistent with the in situ tests: pollution resulted in a decrease in the number of taxa, taxa replacement and in changes in the value of the biotic indices Indice Biótico PAMPeano and Indice de Diatomeas Pampeano, indicating deterioration of water quality. In situ assays have a high potential as environmental tools in integrated approaches of bioassessment programs.     

Response of antioxidant enzymes in freshwater fish populations (Leuciscus alburnoides complex) to inorganic pollutants exposure.

Evidence is accumulating indicating the importance of antioxidant enzyme activity measurements in eco-toxicological studies, as they may constitute markers for exposure to a large variety of pollutants. Variation of antioxidant enzymes, superoxide dismutase (SOD) and glutathione S-transferases (GST) and the effect of heavy metals and selenium exposure on these enzymes were investigated in the livers of Iberian endemic minnows (Leuciscus alburnoides complex) captured in a copper (Cu) mining area. Higher hepatic levels of copper and selenium were always observed in fish captured at the polluted site relative to the reference area population, reflecting the environmental monitoring results. A seasonal fluctuation in zinc and selenium levels for both populations was also observed which could be related to gonad maturation. The activity of SOD did not show significant regional alterations, but a seasonal variation occurred presumably associated with the Leuciscus life cycle. The GST activity was higher in the fish population from the polluted area (except in spring) and GST variability was associated with selenium and copper levels when both regions were compared. The increased GST activity was probably a metabolic adaptation to the continuous exposure to higher levels of those elements.     

Transfer of heavy metals in the food chain earthworm Black-tailed godwit (Limosa limosa): comparison of a polluted and a reference site in The Netherlands

The Black-tailed godwit (Limosa limosa) is a migratory wader that favours wet meadows for breeding. The species has a Red List status in The Netherlands, as it strongly declined in numbers since the 1960s. Intensification of agriculture and land use change resulting in habitat loss are considered major causes of this decline. In some areas the breeding habitat is contaminated with heavy metals. Adult godwits mainly feed on earthworms in the breeding season, which are known to accumulate heavy metals from the soil. In this paper we investigate the transfer of heavy metals from the soil to the Black-tailed godwit, which may have an additive negative effect on the viability of local populations. We measured heavy metal concentrations in soil, earthworms, and godwit eggs and feathers at a polluted and a reference site. The results suggest that Lead, Mercury and Cadmium are transferred from the soil to godwits even though the species spends only a few months in the breeding area during the year.     

活性炭在微污染水源水处理中的应用综述

介绍了活性炭在微污染水源水处理中的应用情况,包括活性炭吸附、生物活性炭、臭氧活性炭技术等的对水源中有机物的去除效果和工艺特点,指出活性炭对去除水中微量有机物污染方面是其他水处理单元难以取代的,在微污染水源水处理中有较广泛的应用.     

Response of antioxidant enzymes in freshwater fish populations (Leuciscus alburnoides complex) to inorganic pollutants exposure

Evidence is accumulating indicating the importance of antioxidant enzyme activity measurements in eco-toxicological studies, as they may constitute markers for exposure to a large variety of pollutants. Variation of antioxidant enzymes, superoxide dismutase (SOD) and glutathione S-transferases (GST) and the effect of heavy metals and selenium exposure on these enzymes were investigated in the livers of Iberian endemic minnows (Leuciscus alburnoides complex) captured in a copper (Cu) mining area. Higher hepatic levels of copper and selenium were always observed in fish captured at the polluted site relative to the reference area population, reflecting the environmental monitoring results. A seasonal fluctuation in zinc and selenium levels for both populations was also observed which could be related to gonad maturation. The activity of SOD did not show significant regional alterations, but a seasonal variation occurred presumably associated with the Leuciscus life cycle. The GST activity was higher in the fish population from the polluted area (except in spring) and GST variability was associated with selenium and copper levels when both regions were compared. The increased GST activity was probably a metabolic adaptation to the continuous exposure to higher levels of those elements.     

Biodiversity of Jal Mahal Lake and Kalakho Lake,Rajasthan, India with special reference to avifauna

This paper reports ecological studies with special reference to avifauna at Jal Mahal Lake (urban) and Kalakho Lake (rural), Rajasthan. Both lakes provide habitats for various migratory and resident birds. More than 180 species of birds, some listed in the Red Data Book, belonging to 49 families were recorded. The birds commonly sighted included some endangered, uncommon, vulnerable, threatened and near threatened species. The overall status of avifaunal species recorded was much better at the less polluted Kalakho Lake than at the Jal Mahal Lake. The human activity around the Jal Mahal Lake and agricultural practices in the dried up area seem to be responsible for the decline in the number of bird species. Drastic regulations are warranted to save these wetlands.     

Feasibility study of wind energy utilization in Saudi Arabia

The wind map of Saudi Arabia indicates that the Kingdom is characterized by the existence of two vast windy regions along the Arabian Gulf and the Red Sea coastal areas. The mean annual wind speed in these two windy regions exceeds 9 knots (16.7 kmph) and ranges from about 14 to 22 kmph and 16 to 19 kmph over the Arabian Gulf and Red Sea coastal areas, respectively. The main characteristic features of the wind field of these regions are presented.Four sample sites are selected for possible installation of both small and large wind energy conversion systems. These sites are: Yenbo and Al-Wajh on the Red Sea coast, Dhahran on the Arabian Gulf coast and Quaisumah in the north east of the Kingdom. The manufacturers pre-mass production unit capital costs ($/kW) are used to estimate the cost of electricity produced, in cents/kW h. The estimated costs of electricity produced by WEC systems of various rated powers when installed at the four sites are presented. A further reduction in the manufacturers unit capital cost is still required to enable wind energy to compete with other conventional energy sources. For oil-producing countries, it may be a few decades before wind energy can become cost-competitive with other energy sources.