Integrative sediment assessment at Atlantic Spanish harbours by means of chemical and ecotoxicological tools

This study refers to the integrative assessment of sediment quality in three harbour areas at the Spanish Atlantic Coast: Vigo (Northwestern Spain), Bilbao and Pasajes (Northern Spain). At each site, two lines of evidence have been considered: chemical analyses (metal, PAH and PCB concentrations in sediments and ammonia concentration in bioassays) and toxicity tests (Microtox®, Corophium sp. marine amphipod and Paracentrotus lividus sea urchin larvae). Chemical and ecotoxicological results have been integrated by means of a tabular matrix and a multivariate factorial analysis (FA). Highly toxic samples have been characterised in Vigo and Pasajes harbours while Bilbao samples present toxicity levels ranging from non-toxic to moderately toxic. High toxicity is associated with high levels of contaminants whereas confounding factors (ammonia, organic matter and mud) have been identified to be the main cause of low to moderate toxicity. Based on the obtained results, it can be concluded that deriving potential toxicity of sediments based on comparison with Sediment Quality Guidelines (SQGs) is in agreement to toxicity results in areas presenting high levels of contaminants. However, at lower levels of toxicity (low to moderate), the mismatch between the potential toxicity (SQG approach) and the toxicity measured by bioassays is greater, as the former only accounts for chemical concentrations, without considering the interaction between contaminants and the effect of confounding factors. Contrarily, the multivariate analysis seems to be a robust tool for the integration and interpretation of different lines of evidence in areas affected by different sources of contamination.     

Addressing criticality for rare earth elements in petroleum refining: The key supply factors approach

The group of elements known as the rare earth elements (REEs) is comprised of the 15 lanthanides. REEs are used in a number of technologies including catalysts for automobiles and petroleum refining, magnets for wind turbines and defense technologies, and phosphors in lighting and computer and TV screens. REEs are actually quite abundant in the earth′s crust. The elements are deemed “rare” because they are found in low concentrations and are difficult to extract economically. China holds 48% of the global REE reserves, and until 2012, production of REEs was almost exclusive to China. Over the past decade, China has been steadily decreasing its REE export quotas, reducing the supply of REEs available to the rest of the world. REEs are considered critical materials according to the National Science and Technology Council, which defines critical elements as those serving an essential function in the manufacture of a product, the absence of which would cause significant social consequence. Thus, it is extremely important for consumers of REEs to be aware of and understand the risks facing the supply REEs, as awareness is the first and most important step in developing strategies to mitigate risk. This report presents a mechanism for identifying the risks present in a supply–demand scenario and determining the criticality of an individual rare earth element under specific circumstances.     

Atmospheric emissions of some POPs in Europe: a discussion of existing inventories and data needs

Accurate and complete information on the emissions of persistent organic pollutants (POPs) are essential for interpreting historical, current and future contamination levels in remote areas. However, this information is also crucial for decision makers aiming at further reduction of the environmental loading of these substances on a regional scale. In this study, we identify and discuss specific POP emission inventory features that are deemed essential to understand, predict and control the behaviour of such substances on a European scale. It is shown that the scientific value of official emission data is limited (e.g. for deriving source–receptor relationships on a European scale), as there is insufficient information on spatial, temporal and compound coverage. Likewise, we argue that non-official emission data (i.e. research-driven emission inventories), which are based on aggregated statistics, may be of limited value for the identification of further emission control strategies. It is thus argued that future emission inventories should be developed in a format that is suitable to serve both policy- and research-oriented applications. Further improvement of official emission data with respect to research-driven features seems to be the most sensible way to proceed. Finally, the empirical basis of current emission inventories remains weak, and further research on emission identification and characterisation seem needed (a) to gain confidence in predicted source–receptor relationship as well as (b) for the development of sound control strategies.     

European environmental assistance to the region of Pskov in northwest Russia: sustainability,effectiveness and implications for environmental governance

The paper explores the impact and sustainability of environmental assistance coming to Russia from EU-based public and private foundations, and its implications for environmental governance. Geographically, the study ’encompassed all the assistance projects awarded in 1991–2016 involving beneficiaries from Pskovskaya Oblast’. This region is potentially an important target for EU investments in environmental infrastructure, due to its location by the EU border and high value of natural capital. The study demonstrates how the assumptions offered by the international aid literature (mostly derived from the global South) apply to Russia. We found major limitations to the assumption that co-financing provided by recipients ensures project effectiveness (demonstrating the acceptance of the donor's agenda) or sustainability (providing interest to the maintenance of outputs). Tangible assets are normally co-financed only if the investment was in agenda anyway (and therefore the donor gets only time gains, although this can be a valid purpose too); soft outputs (plans, surveys, policies, etc.) are usually co-financed in-kind, and therefore cannot secure any additional commitment. Likewise, physical infrastructure often ends up mismanaged due to low or no maintenance budgets available, while maintenance of soft outputs is too much dependent on contextual factors beyond the co-finance paradigm.     

Passive acoustic monitoring of the decline of Mexico's critically endangered vaquita

The vaquita (Phocoena sinus) is the world's most endangered marine mammal with approximately 245 individuals remaining in 2008. This species of porpoise is endemic to the northern Gulf of California, Mexico, and historically the population has declined because of unsustainable bycatch in gillnets. An illegal gillnet fishery for an endangered fish, the totoaba (Totoaba macdonaldi), has recently resurged throughout the vaquita's range. The secretive but lucrative wildlife trade with China for totoaba swim bladders has probably increased vaquita bycatch mortality by an unknown amount. Precise population monitoring by visual surveys is difficult because vaquitas are inherently hard to see and have now become so rare that sighting rates are very low. However, their echolocation clicks can be identified readily on specialized acoustic detectors. Acoustic detections on an array of 46 moored detectors indicated vaquita acoustic activity declined by 80% between 2011 and 2015 in the central part of the species’ range. Statistical models estimated an annual rate of decline of 34% (95% Bayesian credible interval –48% to –21%). Based on results from 2011 to 2014, the government of Mexico enacted and is enforcing an emergency 2‐year ban on gillnets throughout the species’ range to prevent extinction, at a cost of US$74 million to compensate fishers. Developing precise acoustic monitoring methods proved critical to exposing the severity of vaquitas’ decline and emphasizes the need for continual monitoring to effectively manage critically endangered species.     

Inorganic arsenic speciation at river basin scales: The Tinto and Odiel Rivers in the Iberian Pyrite Belt, SW Spain

The Tinto and Odiel rivers are heavily affected by acid mine drainage from mining areas in the Iberian Pyrite Belt. In this work we have conducted a study along these rivers where surface water samples have been collected. Field measurements, total dissolved metals and Fe and inorganic As speciation analysis were performed. The average total concentration of As in the Tinto river (1975 μg L⁻¹) is larger than in the Odiel river (441 μg L⁻¹); however, the mean concentration of As(III) is almost four times higher in the Odiel. In wet seasons the mean pH levels of both rivers (2.4 and 3.2 for the Tinto and Odiel, respectively) increase slightly and the amount of dissolved total arsenic tend to decrease, while the As(III)/(V) ratio strongly increase. Besides, the concentration of the reduced As species increase along the water course. As a result, As(III)/(V) ratio can be up to 100 times higher in the lower part of the basins. An estimation of the As(III) load transported by both rivers into the Atlantic Ocean has been performed, resulting in about 60 kg yr⁻¹ and 2.7 t yr⁻¹ by the Tinto and Odiel rivers, respectively.