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Concept: Environmental impact assessment


Indian Himalayan basins are earmarked for widespread dam building, but aggregate effects of these dams on terrestrial ecosystems are unknown. We mapped distribution of 292 dams (under construction and proposed) and projected effects of these dams on terrestrial ecosystems under different scenarios of land-cover loss. We analyzed land-cover data of the Himalayan valleys, where dams are located. We estimated dam density on fifth- through seventh-order rivers and compared these estimates with current global figures. We used a species-area relation model (SAR) to predict short- and long-term species extinctions driven by deforestation. We used scatter plots and correlation studies to analyze distribution patterns of species and dams and to reveal potential overlap between species-rich areas and dam sites. We investigated effects of disturbance on community structure of undisturbed forests. Nearly 90% of Indian Himalayan valleys would be affected by dam building and 27% of these dams would affect dense forests. Our model projected that 54,117 ha of forests would be submerged and 114,361 ha would be damaged by dam-related activities. A dam density of 0.3247/1000 km(2) would be nearly 62 times greater than current average global figures; the average of 1 dam for every 32 km of river channel would be 1.5 times higher than figures reported for U.S. rivers. Our results show that most dams would be located in species-rich areas of the Himalaya. The SAR model projected that by 2025, deforestation due to dam building would likely result in extinction of 22 angiosperm and 7 vertebrate taxa. Disturbance due to dam building would likely reduce tree species richness by 35%, tree density by 42%, and tree basal cover by 30% in dense forests. These results, combined with relatively weak national environmental impact assessment and implementation, point toward significant loss of species if all proposed dams in the Indian Himalaya are constructed. Efectos Potenciales del Desarrollo Hidroeléctrico Actual y Propuesto sobre la Diversidad Biológica Terrestre en el Himalaya Hindú

Concepts: Biodiversity, River, Extinction, Dam, Impact assessment, Hydroelectricity, Himalayas, Environmental impact assessment


The persistence of chemicals is a key parameter for their environmental risk assessment. Extrapolating their biodegradability potential in aqueous systems to soil systems would improve the environmental impact assessment. This study compares the fate of (14/13)C-labelled 2,4-D (2,4-dichlorophenoxyacetic acid) and ibuprofen in OECD tests 301 (ready biodegradability in aqueous systems) and 307 (soil). 85% of 2,4-D and 68% of ibuprofen were mineralised in aqueous systems, indicating ready biodegradability, but only 57% and 45% in soil. Parent compounds and metabolites decreased to <2% of the spiked amounts in both systems. In soil, 36% of 2,4-D and 30% of ibuprofen were bound in non-extractable residues (NER). NER formation in the abiotic controls was half as high as in the biotic treatments. However, mineralisation, biodegradation and abiotic residue formation are competing processes. Assuming the same extent of abiotic NER formation in abiotic and biotic systems may therefore overestimate the abiotic contribution in the biotic systems. Mineralisation was described by a logistic model for the aquatic systems and by a two-pool first order degradation model for the soil systems. This agrees with the different abundance of microorganisms in the two systems, but precludes direct comparison of the fitted parameters. Nevertheless, the maximum mineralisable amounts determined by the models were similar in both systems, although the maximum mineralisation rate was about 3.5 times higher in the aqueous systems than in the soil system for both compounds; these parameters may thus be extrapolated from aqueous to soil systems. However, the maximum mineralisable amount is calculated by extrapolation to infinite times and includes intermediately formed biomass derived from the labelled carbon. The amount of labelled carbon within microbial biomass residues is higher in the soil system, resulting in lower degradation rates. Further evaluation of these relationships requires comparison data on more chemicals and from different soils.

Concepts: Evaluation, Soil, Environmental remediation, C, Bioremediation, Impact assessment, Extrapolation, Environmental impact assessment


As part of global efforts to reduce dependence on carbon-based energy sources there has been a rapid increase in the installation of renewable energy devices. The installation and operation of these devices can result in conflicts with wildlife. In the marine environment, mammals may avoid wind farms that are under construction or operating. Such avoidance may lead to more time spent travelling or displacement from key habitats. A paucity of data on at-sea movements of marine mammals around wind farms limits our understanding of the nature of their potential impacts.Here, we present the results of a telemetry study on harbour seals Phoca vitulina in The Wash, south-east England, an area where wind farms are being constructed using impact pile driving. We investigated whether seals avoid wind farms during operation, construction in its entirety, or during piling activity. The study was carried out using historical telemetry data collected prior to any wind farm development and telemetry data collected in 2012 during the construction of one wind farm and the operation of another.Within an operational wind farm, there was a close-to-significant increase in seal usage compared to prior to wind farm development. However, the wind farm was at the edge of a large area of increased usage, so the presence of the wind farm was unlikely to be the cause.There was no significant displacement during construction as a whole. However, during piling, seal usage (abundance) was significantly reduced up to 25 km from the piling activity; within 25 km of the centre of the wind farm, there was a 19 to 83% (95% confidence intervals) decrease in usage compared to during breaks in piling, equating to a mean estimated displacement of 440 individuals. This amounts to significant displacement starting from predicted received levels of between 166 and 178 dB re 1 μPa(p-p). Displacement was limited to piling activity; within 2 h of cessation of pile driving, seals were distributed as per the non-piling scenario. Synthesis and applications. Our spatial and temporal quantification of avoidance of wind farms by harbour seals is critical to reduce uncertainty and increase robustness in environmental impact assessments of future developments. Specifically, the results will allow policymakers to produce industry guidance on the likelihood of displacement of seals in response to pile driving; the relationship between sound levels and avoidance rates; and the duration of any avoidance, thus allowing far more accurate environmental assessments to be carried out during the consenting process. Further, our results can be used to inform mitigation strategies in terms of both the sound levels likely to cause displacement and what temporal patterns of piling would minimize the magnitude of the energetic impacts of displacement.

Concepts: Pinniped, Wind power, Wind farm, Floating wind turbine, Wind power in Denmark, Environmental impact assessment, Wind power in the United States, Pile driver


Hydraulic fracturing (fracking) has been used extensively in the US and Canada since the 1950s and offers the potential for significant new sources of oil and gas supply. Numerous other countries around the world (including the UK, Germany, China, South Africa, Australia and Argentina) are now giving serious consideration to sanctioning the technique to provide additional security over the future supply of domestic energy. However, relatively high population densities in many countries and the potential negative environmental impacts that may be associated with fracking operations has stimulated controversy and significant public debate regarding if and where fracking should be permitted. Road traffic generated by fracking operations is one possible source of environmental impact whose significance has, until now, been largely neglected in the available literature. This paper therefore presents a scoping-level environmental assessment for individual and groups of fracking sites using a newly-created Traffic Impacts Model (TIM). The model produces estimates of the traffic-related impacts of fracking on greenhouse gas emissions, local air quality emissions, noise and road pavement wear, using a range of hypothetical fracking scenarios to quantify changes in impacts against baseline levels. Results suggest that the local impacts of a single well pad may be short duration but large magnitude. That is, whilst single digit percentile increases in emissions of CO2, NOx and PM are estimated for the period from start of construction to pad completion (potentially several months or years), excess emissions of NOx on individual days of peak activity can reach 30% over baseline. Likewise, excess noise emissions appear negligible (<1dBA) when normalised over the completion period, but may be considerable (+3.4dBA) in particular hours, especially in night-time periods. Larger, regional scale modelling of pad development scenarios over a multi-decade time horizon give modest CO2 emissions that vary between 2.5 and 160.4kT, dependent on the number of wells, and individual well fracking water and flowback waste requirements. The TIM model is designed to be adaptable to any geographic area where the required input data are available (such as fleet characteristics, road type and quality), and we suggest could be deployed as a tool to help reach more informed decisions regarding where and how fracking might take place taking into account the likely scale of traffic-related environmental impacts.

Concepts: Carbon dioxide, Population density, Natural gas, Greenhouse gas, Emission standard, Kyoto Protocol, Environmental impact assessment, Hydraulic fracturing


ABSTRACT Seeking economic growth and job creation to tackle the nation’s extreme poverty, the Nicaraguan government awarded a concession to build an inter-oceanic canal and associated projects to a recently formed Hong Kong based company with no track record or related expertise. This concession was awarded without a bidding process and in advance of any feasibility, socio-economic or environmental impact assessments; construction has begun without this information. The 278-km long inter-oceanic canal project may result in significant environmental and social impairments. Of particular concern are: damage to Lake Cocibolca, a unique freshwater tropical lake and Central America’s main freshwater reservoir; damage to regional biodiversity and ecosystems; and socio-economic impacts. Concerned about the possibly irreparable damage to the environment and to native communities, conservationists and the scientific community at large are urging the Nicaraguan government to devise and reveal an action plan to address and mitigate the possible negative repercussions of this inter-oceanic canal and associated projects. Critical research needs are herein identified to inform a comprehensive benefit-cost assessment for this megaproject. Keywords: Nicaragua, interoceanic canal, HKND, environmental impacts, social impacts.

Concepts: Natural environment, Environmentalism, Central America, Nicaragua, Environmental impact assessment, Lake Nicaragua, Ometepe, Managua


Assessing and managing the cumulative impacts of human activities on the environment remains a major challenge to sustainable development. This challenge is highlighted by the worldwide expansion of marine renewable energy developments (MREDs) in areas already subject to multiple activities and climate change. Cumulative effects assessments in theory provide decision makers with adequate information about how the environment will respond to the incremental effects of licensed activities and are a legal requirement in many nations. In practise, however, such assessments are beset by uncertainties resulting in substantial delays during the licensing process that reduce MRED investor confidence and limit progress towards meeting climate change targets. In light of these targets and ambitions to manage the marine environment sustainably, reducing the uncertainty surrounding MRED effects and cumulative effects assessment are timely and vital. This review investigates the origins and evolution of cumulative effects assessment to identify why the multitude of approaches and pertinent research have emerged, and discusses key considerations and challenges relevant to assessing the cumulative effects of MREDs and other activities on ecosystems. The review recommends a shift away from the current reliance on disparate environmental impact assessments and limited strategic environmental assessments, and a move towards establishing a common system of coordinated data and research relative to ecologically meaningful areas, focussed on the needs of decision makers tasked with protecting and conserving marine ecosystems and services.

Concepts: Biodiversity, Ecology, Natural environment, Sustainability, Impact assessment, Environmental impact assessment, Strategic Environmental Assessment, Convention on Environmental Impact Assessment in a Transboundary Context


Beetles are the most diverse group of animals, and are crucial for ecosystem functioning. In many countries, they are heavily used for environmental impact assessment, but even in the well-studied Central European fauna, species identification can be very difficult. A comprehensive and taxonomically well curated DNA barcode library could remedy this deficit and also could link hundreds of years of traditional knowledge with next generation sequencing technology. However, such a beetle library is missing to date. This study provides the globally largest DNA barcode reference library for Coleoptera for 15,948 individuals belonging to 3,514 well-identified species (53% of the German fauna) with representatives from 97 of 103 families (94%). This study is the first comprehensive regional test of the efficiency of DNA barcoding for beetles with a focus on Germany. Sequences >500bp were recovered from 63% of the specimens analyzed (15,948 of 25,294) with short sequences from another 997 specimens. Whereas mostspecimens (92.2%) could be unambiguously assigned to a single known species by sequence diversity at CO1, 1089 specimens (6.8%) were assigned to more than one Barcode Index Number (BIN), creating 395 BINs which need further study to ascertain if they represent cryptic species, mitochondrial introgression, or simply regional variation in widespread species. We found 409 specimens (2.6%) that shared a BIN assignment with another species, most involving a pair of closely allied species as 43 BINs were involved. Most of these taxa were separated by barcodes although sequence divergences were low. Only 155 specimens (0.97%) show identical or overlapping clusters. This article is protected by copyright. All rights reserved.

Concepts: Species, Germany, Beetle, DNA barcoding, Barcode, Cryptic species complex, Identification, Environmental impact assessment


This review summarizes the recent research and development pertaining to the topic of mine drainage which were published in 2016 and early 2017. The review includes three main sections: Mine Drainage and its Environmental Impact, Prediction and Prevention, and Treatment Technologies. The first section covers the characterization of mine drainage and its related environmental impacts, including three subsections focused on physiochemical characterization, microbiological characterization, and environmental impacts. The second section of the review is divided into two subsections focused on either the prediction or prevention of acid mine drainage. The final section focuses on treatment technologies for mine drainage, including physiochemical treatment, biological treatment, passive treatment, and beneficial uses of mine drainage and treatment wastes.

Concepts: The Final, Innovation, Research and development, Section, Acid mine drainage, Environmental impact assessment


The construction of high-voltage direct current (HVDC) lines for the long-distance transport of energy is becoming increasingly popular. This has raised public concern about potential environmental impacts of the static electric fields (EF) produced under and near HVDC power lines. As the second part of a comprehensive literature analysis, the aim of this systematic review was to assess the effects of static EF exposure on biological functions in invertebrates and plants and to provide the basis for an environmental impact assessment of such exposures.

Concepts: Electricity, Direct current, Electrical engineering, Rectifier, Environmental impact assessment, Thomas Edison, Electric power transmission, High-voltage direct current


Hydrodynamics and sediment transport are key physical processes contributing to habitat structure within the marine environment. Coastal development that results in the alteration of these processes (e.g., changing water flushing and/or sedimentation rates) can have detrimental impacts on sensitive systems. This is a current relevant issue in Qatar as its coastal regions continue to be developed, not only around the capital of Doha, but in many areas around this Arabian Gulf peninsula. The Northeastern Qatari coast is comprised of diverse and sensitive flora and fauna such as seagrass and macro-algae meadows, coral reefs/patches, turtles and dugongs that tolerate harsh environmental conditions. In the near future, this area may see a rise in anthropogenic activity in the form of coastal development projects. These will add to existing natural stresses, such as high temperature, high salinity and low rates of precipitation. Consequently, there is a need to characterize this area and assess the potential impacts that these anthropogenic activities may have on the region. In this study, a novel sediment transport model is described and used to demonstrate the potential impact of altering hydrodynamics and subsequent sediment transport along the northeastern Qatar near shore marine environment. The developed models will be tested using potential scenarios of future anthropogenic activities forecasted to take place in the area. The results will show the effects on water and sediment behavior, and provide a scientificapproach for key stakeholders to make decisions with respect to the management of the considered coastal zone. Furthermore, it provides a tool / framework that can be utilized in environmental impact assessment and associated hydrodynamic studies along other areas of the Qatari coastal zone. This article is protected by copyright. All rights reserved.

Concepts: Water, Sediment, Arabian Peninsula, Environmental science, Qatar, Persian Gulf, Environmental impact assessment, Sediment transport