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Available methods for measuring the impact of ocean acidification (OA) and leakage from carbon capture and storage (CCS) on marine sedimentary pH profiles are unsuitable for replicated experimental setups. To overcome this issue, a novel optical sensor application is presented, using off-the-shelf optode technology (MOPP). The application is validated using microprofiling, during a CCS leakage experiment, where the impact and recovery from a high CO2 plume was investigated in two types of natural marine sediment. MOPP offered user-friendliness, speed of data acquisition, robustness to sediment type, and large sediment depth range. This ensemble of characteristics overcomes many of the challenges found with other pH measuring methods, in OA and CCS research. The impact varied greatly between sediment types, depending on baseline pH variability and sediment permeability. Sedimentary pH profile recovery was quick, with profiles close to control conditions 24 h after the cessation of the leak. However, variability of pH within the finer sediment was still apparent 4 days into the recovery phase. Habitat characteristics need therefore to be considered, to truly disentangle high CO2 perturbation impacts on benthic systems. Impacts on natural communities depend not only on the pH gradient caused by perturbation, but also on other processes that outlive the perturbation, adding complexity to recovery.

AbstractResting egg production is considered the most common form of dormancy in aquatic invertebrates. Given that many taxa at least partially terminate resting egg state using environmental cues, knowledge on environmental drivers of hatching success is important, particularly within the context of climate change and environmental degradation. Fairy shrimp (anostracans) are temporary wetland specialists that are reliant on resting egg production for population persistence. Temporary wetlands are common in many arid regions projected to experience increases in temperature, and in areas often compromised by human‐mediated activities. In this study, we assessed the combined effects of light and temperature on the hatching success of Streptocephalus cafer (Anostraca) dormant eggs from temporary wetlands in an arid environment. Both temperature and light altered hatching success, with emergent effects evident. Light caused a significant threefold increase in hatching success overall, while temperature effects were non‐linear, with hatching optimised at 27°C, and especially under light conditions. These results are discussed within the context of shifting climates and disturbances to temporary wetland ecosystems.

Increasing concerns regarding oil spills, air pollution, and climate change associated with fossil fuel use have increased the urgency of the search for renewable, clean sources of energy. This assessment describes the potential of Ocean Thermal Energy Conversion (OTEC) to produce not only clean energy but also potable water, refrigeration, and aquaculture products. Higher oil prices and recent technical advances have improved the economic and technical viability of OTEC, perhaps making this technology more attractive and feasible than in the past. Relatively high capital costs associated with OTEC may require the integration of energy, food, and water production security in small island developing states (SIDSs) to improve cost-effectiveness. Successful implementation of OTEC at scale will require the application of insights and analytical methods from economics, technology, materials engineering, marine ecology, and other disciplines as well as a subsidized demonstration plant to provide operational data at near-commercial scales.

Abstract Next generation turbines can be installed to exploit tidal energy resource in estuaries. However, the ecological implications of such deployments remain unknown. Accordingly, this study is focused on the impact of tidal farms on intertidal areas and associated waterbird habitats in estuaries. A numerical model simulates the hydrodynamic conditions of the Solway Firth, comprising one of the most extensive intertidal zones in the UK. The effects of tidal farms with different turbine densities have been evaluated in terms of changes to the areas of habitat for wetland bird species of conservation importance. The results suggest that any habitat loss may be minor and that in some cases there may be an increase (also small) in the area of important habitat. The percentage change in intertidal areas is also considerably lower than that expected to result from tidal barrages of similar capacities, implying the potential for tidal farms to present an alternative solution for exploiting tidal energy in highly protected areas. The changes in the extent of intertidal habitat are not proportional to the energy dissipated by the tidal farm. Therefore a range of tidal farm designs should be evaluated in order to optimise installed capacity while minimising habitat loss. However, the site-dependency of the impacts and the complex responses to change of estuarine ecosystems reinforce the requirement for detailed studies to be undertaken for each specific location and array configuration. The methodology presented here is appropriate for such assessments as it can be applied to different locations and turbine types.

Presently, two Chlorella sorokiniana strains sampled during summer (CS-S) and winter (CS-W) from a maturation pond and isolated by dominance were studied on their behavior on temperature and light extremes in batch experiments. Although both strains showed no differences in their tolerance of temperatures up to 45 °C, the growth rates, pigment contents and fatty acid compositions in response to PAR at 700 and 1,500 µmol m-2sec-1 differed. CS-W was less affected by photoinhibition and maintained constantly high growth rates. High radiation resulted in both strains in an equivalent decrease of chlorophyll a and accessory pigments indicating that the latter did not function as a light filter. PUFAS (18:3 and 16:3) increased in CS-W at high radiation by > 60% and decreased in CS-S by 8 %. Results indicate that CS-W is highly favorable for mass cultivation particularly in outdoors, in which diurnal variations of solar radiation occur.

BACKGROUND Municipal bio-wastes (MBW) yield soluble bio-based substances (SBO) by anaerobic digestion, composting and chemical hydrolysis. The SBO are known valuable products for multiple uses in the chemical industry, agriculture and animal husbandry. The present work investigates a new SBO property, i.e. reducing the ammonia content in MBW anaerobic digestates. Thus, MBW were fermented under anaerobic conditions with 0.05 or 0.20% SBO added. RESULTS Fermentations were carried out at 55 °C for 14 days using nine batch reactors of 6.5 L capacity working in parallel, each containing 4 L MBW slurry (100 g volatile solids). The control and SBO 0.05% reactors produced 70 L of biogas, and 1.2 g and 0.11 g ammonia N, respectively. The SBO 0.20% reactors produced 73 L biogas and a digestate containing 0.32 g less ammonia N than the starting ammonia content. Oxidation of ammonia to N2 promoted by SBO seemed the most likely reason for the ammonia reduction. The process benefits were evaluated in comparison with conventional technology for the abatement of ammonia. CONCLUSIONS Integration of biochemical and chemical technology yielding multipurpose products from MBW is a potentially viable cost-effective feasible route to turn a MBW treatment plant into a biorefinery. © 2015 Society of Chemical Industry

Abstract The life cycle cost and environmental impacts of electric vehicles are very uncertain, but extremely important for making policy decisions. This study presents a new model, called the Electric Vehicles Regional Optimizer, to model this uncertainty and predict the optimal combination of drivetrains in different U.S. regions for the year 2030. First, the life cycle cost and life cycle environmental emissions of internal combustion engine vehicles, gasoline hybrid electric vehicles, and three different Electric Vehicle types (gasoline plug-in hybrid electric vehicles, gasoline extended range electric vehicle, and all-electric vehicle) are evaluated considering their inherent uncertainties. Then, the environmental damage costs and the water footprint of the studied drivetrains are estimated. Additionally, using an Exploratory Modeling and Analysis method, the uncertainties in the life cycle cost, environmental damage cost, and water footprint of studied vehicle types are modeled for different U.S. electricity grid regions. Finally, an optimization model is coupled with Exploratory Modeling and Analysis to find the ideal combination of different vehicle types in each U.S. region for the year 2030. The findings of this research will help policy makers and transportation planners to prepare our nation's transportation system for the influx of electric vehicles.

Environmental perturbation, climate change and international commerce are important drivers for biological invasions. Climate anomalies can further increase levels of habitat disturbance and act synergistically to elevate invasion risk. Herein, we use a historical data set from the upper San Francisco Estuary to provide the first empirical evidence for facilitation of invasions by climate extremes. Invasive zooplankton species did not become established in this estuary until the 1970s when increasing propagule pressure from Asia coincided with extended drought periods. Hydrological management exacerbated the effects of post-1960 droughts and reduced freshwater inflow even further, increasing drought severity and allowing unusually extreme salinity intrusions. Native zooplankton experienced unprecedented conditions of high salinity and intensified benthic grazing, and life history attributes of invasive zooplankton were advantageous enough during droughts to outcompete native species and colonise the system. Extreme climatic events can therefore act synergistically with environmental perturbation to facilitate the establishment of invasive species.