Oil Contamination in Ogoniland, Niger Delta

The study shows extensive oil contamination of rivers, creeks, and ground waters in Ogoniland, Nigeria. The levels found in the more contaminated sites are high enough to cause severe impacts on the ecosystem and human health: extractable petroleum hydrocarbons (EPHs) (>10-C40) in surface waters up to 7420 μg L⁻¹, drinking water wells show up to 42 200 μg L⁻¹, and benzene up to 9000 μg L⁻¹, more than 900 times the WHO guidelines. EPH concentrations in sediments were up to 17 900 mg kg⁻¹. Polycyclic aromatic hydrocarbons concentrations reached 8.0 mg kg⁻¹, in the most contaminated sites. The contamination has killed large areas of mangroves. Although the natural conditions for degradation of petroleum hydrocarbons are favorable with high temperatures and relatively high rainfall, the recovery of contaminated areas is prevented due to the chronic character of the contamination. Oil spills of varying magnitude originates from facilities and pipelines; leaks from aging, dilapidated, and abandoned infrastructure; and from spills during transport and artisanal refining of stolen oil under very primitive conditions.

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Valuation of ecotoxicological impacts from tributyltin based on a quantitative environmental assessment framework

In the scientific literature, few valuations of biodiversity and ecosystem services following the impacts of toxicity are available, hampered by the lack of ecotoxicological documentation. Here, tributyltin is used to conduct a contingent valuation study as well as cost–benefit analysis (CBA) of measures for improving the environmental status in Swedish coastal waters of the Baltic Sea. Benefits considering different dimensions when assessing environmental status are highlighted and a quantitative environmental assessment framework based on available technology, ecological conditions, and economic valuation methodology is developed. Two scenarios are used in the valuation study: (a) achieving good environmental status by 2020 in accordance with EU legislation (USD 119 household⁻¹ year⁻¹) and (b) achieving visible improvements by 2100 due to natural degradation (USD 108 household⁻¹ year⁻¹) during 8 years. The later scenario was used to illustrate an application of the assessment framework. The CBA results indicate that both scenarios might generate a welfare improvement.

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Estimating biodiversity impacts without field surveys: A case study in northern Borneo

In many regions of the world, biodiversity surveys are not routinely conducted prior to activities that lead to land conversion, such as development projects. Here we use top-down methods based on global range maps and bottom-up methods based on macroecological scaling laws to illuminate the otherwise hidden biodiversity impacts of three large hydroelectric dams in the state of Sarawak in northern Borneo. Our retrospective impact assessment finds that the three reservoirs inundate habitat for 331 species of birds (3 million individuals) and 164 species of mammals (110 million individuals). A minimum of 2100 species of trees (900 million individuals) and 17 700 species of arthropods (34 billion individuals) are estimated to be affected by the dams. No extinctions of bird, mammal, or tree species are expected due to habitat loss following reservoir inundation, while 4–7 arthropod species extinctions are predicted. These assessment methods are applicable to any data-limited system undergoing land-use change.

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Sustainable farming practices of the Chinese mitten crab (<Emphasis Type="Italic">Eriocheir sinensis)</Emphasis> around Hongze Lake,lower Yangtze River Basin,China

Results of a survey of 156 Chinese mitten crab (Eriocheir sinensis) grow-out farms around Hongze Lake (118.48–118.72°E; 33.36–33.38°N) are reported. Area farmed has remained relatively unchanged but production (59 932 t in 2012) increased steadily over the last 7 years, indicative of the viability and sustainability of the farming system that has gradually replaced intensive Chinese major carp polyculture around Hongze Lake. Results showed that production range was 135–2400 kg ha⁻¹ cycle⁻¹ (mean 1144 ± 34). Crab yields correlated linearly to stocking density and conformed to a normal distribution curve, with 66.7 % of farms yielding 900 kg ha⁻¹ cycle⁻¹ or more. Yield was negatively correlated to pond size and capture size (p < 0.01), and farms with macrophyte coverage rate lower than 30 % of water surface were significantly (p < 0.05) lower than those exceeding 30 %.

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Improving Oxygen Conditions in the Deeper Parts of Bornholm Sea by Pumped Injection of Winter Water

Vertical diffusivity and oxygen consumption in the basin water, the water below the sill level at about 59 m depth, have been estimated by applying budget methods to monitoring data from hydrographical stations BY4 and BY5 for periods without water renewal. From the vertical diffusivity, the mean rate of work against the buoyancy forces below 65 m depth is estimated to about 0.10 mW m⁻². This is slightly higher than published values for East Gotland Sea. The horizontally averaged vertical diffusivity κ can be approximated by the expression κ = a₀N⁻¹ where N is the buoyancy frequency and a₀ ≈ 1.25 × 10⁻⁷ m² s⁻², which is similar to values for a₀ used for depths below the halocline in Baltic proper circulation models for long-term simulations. The contemporary mean rate of oxygen consumption in the basin water is about 75 g O₂ m⁻² year⁻¹, which corresponds to an oxidation of 28 g C m⁻² year⁻¹. The oxygen consumption in the Bornholm Basin doubled from the 1970s to the 2000s, which qualitatively explains the observed increasing frequency and vertical extent of anoxia and hypoxia in the basin water in records from the end of the 1950s to present time. A horizontally averaged vertical advection–diffusion model of the basin water is used to calculate the effects on stratification and oxygen concentration by a forced pump-driven vertical convection. It is shown that the residence time of the basin water may be reduced by pumping down and mixing the so-called winter water into the deepwater. With the present rate of oxygen consumption, a pumped flux of about 25 km³ year⁻¹ would be sufficient to keep the oxygen concentration in the deepwater above 2 mL O₂ L⁻¹.     

荧光原位杂交技术在环境微生物生态学解析中的应用研究

近年来 ,诸多国家在环境微生物领域先后开展了分子生物学研究方法的建立和生物学评价工作。一些不依靠纯培养的微生物群落的分析方法已得到广泛应用和发展。荧光原位杂交 (FISH)技术 ,具有细胞在测定过程中不被破坏、形状不改变、特异性强、能够真实反映在自然环境下微生物的情况及分布等特点 ,在环境微生物群落探测分析中已逐渐被广泛应用。该技术利用带有荧光标记的特异性寡核苷酸探针 ,与细胞内相应的靶核糖体结合 ,能将微生物探测、鉴定到属和种的水平。运用于硝化细菌、除磷细菌和丝状微生物等废水处理中常见的特征性微生物种群和群落生态学研究中 ,颇为高效。该技术的应用避免了传统培养方法进行鉴定和计数的局限性 ,在环境微生物生态学解析中具有较高应用价值。     

Human-mediated dispersal of aquatic invertebrates with waterproof footwear

Human-mediated dispersal has rarely been considered in wetland conservation strategies at regional scales, yet high concern exists about this aspect for (inter-)national management considering invasive species in other aquatic systems. In this context, we aim at understanding the role of human-mediated dispersal by footwear in protected wetlands with high conservation value. Zooplankton and zoobenthos were sampled in 13 shallow lakes in central Spain and, at the same time, mud attached to waders was collected and later cultured in deionized water under laboratory conditions for 4 weeks. Two-hundred and four individuals belonging to 19 invertebrate taxa were recovered after hatching; Ostracoda (84 %), Cladocera (53 %), Copepoda (30 %), Anostraca (30 %), and Notostraca (7 %) were the most frequent groups among the hatched crustaceans. NMDS and PERMANOVA analyses showed significant differences between the dispersed (via footwear) and the source active metacommunity, suggesting different dispersal abilities among the species found. Human vectors facilitate dispersal among protected lakes, which could eventuality lead to biotic homogenization and faster spread of non-indigenous species. Preservation strategies and education campaigns associated to target humans in close contact with water bodies should be imperative in conservation management of protected lakes.

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On the decline of ground lichen forests in the Swedish boreal landscape: Implications for reindeer husbandry and sustainable forest management

Lichens are a bottleneck resource for circumpolar populations of reindeer, and as such, for reindeer husbandry as an indigenous Sami land-use tradition in northern Sweden. This study uses ground lichen data and forest information collected within the Swedish National Forest Inventory since 1953, on the scale of northern Sweden. We found a 71 % decline in the area of lichen-abundant forests over the last 60 years. A decline was observed in all regions and age classes and especially coincided with a decrease of >60 year old, open pine forests, which was the primary explanatory factor in our model. The effects of reindeer numbers were inconclusive in explaining the decrease in lichen-abundant forest. The role that forestry has played in causing this decline can be debated, but forestry can have a significant role in reversing the trend and improving ground lichen conditions.

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Total and Methylmercury in Soft Tissues of White-Tailed Eagle (Haliaeetus albicilla) and Osprey (Pandion haliaetus) Collected in Poland

Mercury (Hg) contamination in piscivorous birds, especially methylmercury (MeHg), has been drawing much attention worldwide in regard to its bioaccumulation and biomagnification in food chains. In this study on Hg in the soft tissues of white-tailed eagles (n = 22) and ospreys (n = 2) from Poland, total Hg (THg) range was 0.15–47.6 while MeHg range was 0.11–8.05 mg kg⁻¹ dry weight. In both species, median THg and MeHg concentrations were lower in the muscle and brain than in the liver and kidney. Median nephric residues were just under 3 and 5 mgTHg kg⁻¹ or 0.9 and 3.7 mgMeHg kg⁻¹ for white-tailed eagle and osprey, respectively. In Norwegian data from the 1970s and in our results, MeHg in the muscle of white-tailed eagle was ~60 % THg (%MeHg = MeHg/THg × 100), lower than in other piscivorous birds. A clear similarity in THg tissue levels was found between Polish and German populations of white-tailed eagles.     

Waterfowl foraging in winter-flooded ricefields: Any agronomic benefits for farmers?

Winter-flooding of ricefields provides foraging habitat to waterfowl, which in return may bring agronomic benefits to farmers. Our study experimentally tested the effect of mallards (Anas platyrhynchos) on the standing stalks and weed seed bank in the Camargue (France), both of which present major challenges for farmers. Three duck densities were tested: (D1) 5 ducks ha⁻¹ (historical nocturnal density), (D2) 23 ducks ha⁻¹ (present nocturnal density), and (D3) 300 ducks ha⁻¹ (Asian rice-duck farming density). The ducks reduced the stalks significantly: −27 % (D1), −52 % (D2), and −91 % (D3). Conversely, they decreased the number of seeds by only 3 % (D3) and the seed mass by about 21 % (D1 and D3), which was not significant. Besides they had no effect on seed species richness. This study clearly demonstrates that the winter-flooding effect on straw decomposition can be enhanced by waterfowl foraging, hence showing an agronomic benefit from ducks to farmers. However, there was no clear effect in terms of seed bank reduction.     

生物强化系统微生物分子诊断技术的应用及新发展

现代分子生物技术的飞速发展及其在环境研究领域的应用,为生物强化技术的研究和发展提供了新方法和新思路.本文从生物强化系统特异微生物检测及定量化技术、生物强化系统微生物群落结构组成及动态演替规律研究、生物强化作用机制的分子生物学解析、生物强化菌的基因工程构建、生物强化系统微生物的安全释放及控制技术几方面,对生物强化系统微生物分子诊断技术的应用和发展作了较为全面的综述.     

The sensitivity of current and future forest managers to climate-induced changes in ecological processes

Climate vulnerability of managed forest ecosystems is not only determined by ecological processes but also influenced by the adaptive capacity of forest managers. To better understand adaptive behaviour, we conducted a questionnaire study among current and future forest managers (i.e. active managers and forestry students) in Austria. We found widespread belief in climate change (94.7 % of respondents), and no significant difference between current and future managers. Based on intended responses to climate-induced ecosystem changes, we distinguished four groups: highly sensitive managers (27.7 %), those mainly sensitive to changes in growth and regeneration processes (46.7 %), managers primarily sensitive to regeneration changes (11.2 %), and insensitive managers (14.4 %). Experiences and beliefs with regard to disturbance-related tree mortality were found to particularly influence a manager’s sensitivity to climate change. Our findings underline the importance of the social dimension of climate change adaptation, and suggest potentially strong adaptive feedbacks between ecosystems and their managers.

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Sewage-exposed marine invertebrates: survival rates and microbiological accumulation

A large number of bacteria, including agents responsible for diseases, characterise sewage-polluted seawaters. Apart from standards for bathing waters and bivalve aquaculture waters, there are no general microbiological standards applicable to seawaters to help decide if bacterial pollution is within acceptable ranges. This study represents an attempt towards the issue of comparing the susceptibility of different marine invertebrates subjected to polluted seawater with a high microbial contamination. We explored the survival rates and the microbiological accumulation of mollusc bivalves, echinoderms and crustaceans species exposed to sewage-polluted seawaters. Microbiological analyses were performed on the polluted seawater and on the homogenates of exposed and unexposed specimens. Culturable bacteria (22 °C and 37 °C) and microbial pollution indicators (total coliforms, Escherichia coli and intestinal enterococci) were measured. When exposed to the sewage-polluted seawater, the examined invertebrates showed different survival rates. In the filter feeders, bacterial densities at 22 °C and 37 °C rose after 96 h of exposure to sewage. The highest concentrations of total coliforms and intestinal enterococci were found in exposed bivalve Mytilus galloprovincialis. The concentrations of bacteria growing at 37 °C were lower in the exposed deposit feeders compared to the polluted seawater. Some yeasts were absent in several exposed species although these yeasts were present in the polluted seawater. Our data suggest that the examined filter feeders, given their capability to survive and accumulate bacteria, may counteract the effects of sewage and restore seawater quality.     

Socio-economic vulnerability to climate change in the central mountainous region of eastern Mexico

Climate change effects are expected to be more severe for some segments of society than others. In Mexico, climate variability associated with climate change has important socio-economic and environmental impacts. From the central mountainous region of eastern Veracruz, Mexico, we analyzed data of total annual precipitation and mean annual temperature from 26 meteorological stations (1922–2008) and from General Circulation Models. We developed climate change scenarios based on the observed trends with projections to 2025, 2050, 2075, and 2100, finding considerable local climate changes with reductions in precipitation of over 700 mm and increases in temperature of ~9°C for the year 2100. Deforested areas located at windward were considered more vulnerable, representing potential risk for natural environments, local communities, and the main crops cultivated (sugarcane, coffee, and corn). Socio-economic vulnerability is exacerbated in areas where temperature increases and precipitation decreases.

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Biologic impact on the coastal belt of the province of Venice (Italy,Northern Adriatic Sea): preliminary analysis for the characterization of the bathing water profile

Background, aim and scope  

This paper presents a preliminary study of the water profile with reference to microbiological parameters, required by Directive 2006/07/EC (European Community 2006) concerning the management of bathing water quality, in the coastal belt of the Province of Venice (Italy, Northern Adriatic Sea). A historical database has been implemented with monitoring data for the period 2000–2006 (data on rivers, bathing and marine coastal waters and on the characterization of Wastewater Treatment Plant (WWTP) discharges) from the institutional activity of Veneto Regional Environmental Prevention and Protection Agency (ARPAV). An integrated areal analysis for the microbiological investigation of homogeneous stretches along the coast of the Province of Venice was performed for a preliminary characterization of the bathing water profile considering water quality status and existing pressure sources.     

Climate Change and Population Growth in Timor Leste: Implications for Food Security

The climate in Timor Leste (East Timor) is predicted to become about 1.5 °C warmer and about 10 % wetter on average by 2050. By the same year, the population is expected to triple from 1 to 2.5–3 million. This article maps the predicted changes in temperature and rainfall and reviews the implications of climate change and population growth on agricultural systems. Improved cultivars of maize, rice, cassava, sweet potato and peanuts with high yield performance have been introduced, but these will need to be augmented in the future with better adapted cultivars and new crops, such as food and fodder legumes and new management practices. The requirements for fertilizers to boost yields and terracing and/or contour hedgerows to prevent soil erosion of steeply sloping terrain are discussed. Contour hedges can also be used for fodder for improved animal production to provide protein to reduce malnutrition.     

Climate Variability and Environmental Stress in the Sudan-Sahel Zone of West Africa

Environmental change in the Sudan-Sahel region of West Africa (SSWA) has been much debated since the droughts of the 1970s. In this article we assess climate variability and environmental stress in the region. Households in Senegal, Mali, Burkina Faso, Niger, and Nigeria were asked about climatic changes and their perceptions were compared across north–south and west–east rainfall gradients. More than 80% of all households found that rainfall had decreased, especially in the wettest areas. Increases in wind speeds and temperature were perceived by an overall 60–80% of households. Contrary to household perceptions, observed rainfall patterns showed an increasing trend over the past 20 years. However, August rainfall declined, and could therefore potentially explain the contrasting negative household perceptions of rainfall trends. Most households reported degradation of soils, water resources, vegetation, and fauna, but more so in the 500–900 mm zones. Adaptation measures to counter environmental degradation included use of manure, reforestation, soil and water conservation, and protection of fauna and vegetation. The results raise concerns for future environmental management in the region, especially in the 500–900 mm zones and the western part of SSWA.     

Invisible Face of Boron Pollution in Fluvial Ecosystem: The Level in the Tissues of Sentinel and Nectonic Organisms

Turkey is the largest producer of borate products in the world. Among four largest boron mines in Turkey two of them are located in basins of Orhaneli and Emet Streams. In this study, boron levels in abiotic (water–sediment) and some biotic elements (sentinel organisms; Asellus aquaticus, Gammarus pulex,Chironomus tentans, Limnodrilus hoffmeisteri and nektonic organism; Squalius cii) of Orhaneli and Emet Streams were investigated and their ranks among the food chain were demonstrated. Since Orhaneli and Emet Streams confluence to form Mustafakemalpaşa Brook which feeds Uluabat Lake which is one of the most important Ramsar fields of the world, Boron levels in those two streams have importance in terms of both continuances of aquatic systems. Present study results have shown that boron levels in water of both streams are much higher (vary between 8.64 and 16.73 mg L⁻¹) than not only Turkish Standard but also limits determined by WHO, US EPA, and NAS. Boron levels determined in sediments of two streams vary between 18.05 and 36.7 mg kg⁻¹. The highest boron level in the biotic elements was determined in liver of Squalius cii (34.64 mg kg⁻¹), it is followed by Limnodrilus hoffmeisteri (2.84 mg kg⁻¹), Chironomus tentans (2.11 mg kg⁻¹), and Gammarus pulex (1.98 mg kg⁻¹).     

Comparative analysis of the structure of carbon materials relevant in combustion

The determination of the structure of carbon materials is an analytical problem that join the research scientific communities involved in the chemical characterization of heavy fuel-derived products (heavy fuel oils, coal-derived fuels, shale oil, etc.) and of carbon materials (polycyclic aromatic compounds, tar, soot) produced in many combustion processes.

The knowledge of the structure of these “difficult” fuels and of the carbon materials produced by incomplete combustion is relevant to research for the best low-environmental impact operation of combustion systems; but an array of many analytical and spectroscopic tools are necessary, and often not sufficient, to attempt the characterization of such complex products and in particular to determine the distribution of molecular masses.

In this paper the size exclusion chromatography using N-methyl-pyrrolidinone as eluent has been applied for the characterization of different carbon materials starting from typical carbon species, commercially available like polyacenaphthylene, carbon black, naphthalene pitch up to combustion products like soot and soot extract collected in fuel-rich combustion systems. Two main fractions were detected, separated and molecular weights (MWs) determined by comparison with polystyrene standards: a first fraction consisted of particles with very large molecular masses (>100 000 u); a second fraction consisted of species in a relatively small MW range (200–600 u). The distribution of these fractions changes in dependence on the carbon sample characteristics.

Fluorescence spectroscopy applied on the fractions separated by size-exclusion chromatography has been used and comparatively interpreted giving indications on the differences and similarities in chemical structure of such different materials.     

Evidence for Acidification-Driven Ecosystem Collapse of Danish Erica tetralix Wet Heathland

We report observations of disappearance of Erica tetralix in wet heathland, which is unlikely to be caused by competition, as E. tetralix is dying before its place is taken up by other species. To investigate the causes, we used both old and new data. Results showed that presence of Molinia caerulea and Calluna vulgaris were substantial in the former E. tetralix dominated areas. Measurements of the C/N ratio in the morlayer were between 21 and 26 under the E. tetralix stands. As the expected C/N ratio in a healthy nutrient poor ecosystem like the E. tetralix wet heathland is around 30, this indicates that the ratio is probably decreasing and, correspondingly, the probability of nitrogen leaching from the ecosystem is increasing. The morlayer pH was extremely low—between 3.03 and 3.78. This represents a pH decline since the 1960s, where pH values generally were above 4. This supports the hypothesis that the decrease in morlayer pH is the major factor explaining the disappearance of E. tetralix and that measures to increase pH should be considered as part of the recommendations for relevant future management.

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