Integrated assessment of CCS in the German power plant sector with special emphasis on the competition with renewable energy technologies

The study presents the results of an integrated assessment of carbon capture and storage (CCS) in the power plant sector in Germany, with special emphasis on the competition with renewable energy technologies. Assessment dimensions comprise technical, economic and environmental aspects, long-term scenario analysis, the role of stakeholders and public acceptance and regulatory issues. The results lead to the overall conclusion that there might not necessarily be a need to focus additionally on CCS in the power plant sector. Even in case of ambitious climate protection targets, current energy policy priorities (expansion of renewable energies and combined heat and power plants as well as enhanced energy productivity) result in a limited demand for CCS. In case that the large energy saving potential aimed for can only partly be implemented, the rising gap in CO₂ reduction could only be closed by setting up a CCS-maximum strategy. In this case, up to 22% (41 GW) of the totally installed load in 2050 could be based on CCS. Assuming a more realistic scenario variant applying CCS to only 20 GW or lower would not be sufficient to reach the envisaged climate targets in the electricity sector. Furthermore, the growing public opposition against CO₂ storage projects appears as a key barrier, supplemented by major uncertainties concerning the estimation of storage potentials, the long-term cost development as well as the environmental burdens which abound when applying a life-cycle approach. However, recently, alternative applications are being increasingly considered?Cthat is the capture of CO₂ at industrial point sources and biomass based energy production (electricity, heat and fuels) where assessment studies for exploring the potentials, limits and requirements for commercial use are missing so far. Globally, CCS at power plants might be an important climate protection technology: coal-consuming countries such as China and India are increasingly moving centre stage into the debate. Here, similar investigations on the development and the integration of both, CCS and renewable energies, into the individual energy system structures of such countries would be reasonable.     

Precipitation-driven decrease in wildfires in British Columbia

Trends of summer precipitation and summer temperature and their influence on trends in summer drought and area burned in British Columbia (BC) were investigated for the period 1920–2000. The complexity imposed by topography was taken into account by incorporating high spatial resolution climate and fire data. Considerable regional variation in trends and in climate–fire relationships was observed. A weak but significant increase in summer temperature was detected in northeastern and coastal BC, whereas summer precipitation increased significantly in all regions—by up to 45.9 %. A significant decrease in province-wide area burned and at the level of sub-units was strongly related to increasing precipitation, more so than to changing temperature or drought severity. A stronger dependence of area burned on precipitation, a variable difficult to predict, implies that projected changes in future area burned in this region may yield higher uncertainties than in regions where temperature is predominantly the limiting factor for fire activity. We argue that analyses of fire–climate relationships must be undertaken at a sufficiently high resolution such that spatial variability in limiting factors on area burned like precipitation, temperature, and drought is captured within units.     

Contaminants in water: non-target UHPLC/MS analysis

Contamination of water resources is one of the major problems to be faced for environment preservation and sustainability. The monitoring of target compounds based on mass spectrometry and selected reaction monitoring mode is often insufficient to definitely assess the quality of surface water. Also potentially harmful non-target pollutants simultaneously present must be taken into account. Liquid chromatography coupled with tandem mass spectrometry is suitable to obtain complete information on water composition. Hybrid mass spectrometers such as triple quadrupole/linear ion trap, hybrid quadrupole/time-of-flight and linear ion trap/orbitrap analyzers should be used. Here, we review ultra-high performance liquid chromatography coupled with mass spectrometry methods developed for post-target and non-target screening analysis of water emerging contaminants, such as pesticides and their degradation products, pharmaceuticals and drug side-reaction products, surfactants and illicit drugs. The major points are the following: (1) the possibility of performing retrospective analysis only by high-resolution mass analyzer; (2) the compatibility of mass analyzer with ultra-high performance liquid chromatography; (3) the use of deconvolution software to detect unknowns; and (4) the limited availability of library database.     

A decade of investigations on groundwater arsenic contamination in Middle Ganga Plain,India

Groundwater arsenic (As) load in excess of drinking limit (50 µg L^?1) in the Gangetic Plains was first detected in 2002. Though the menace was known since about two decades from the downstream part of the plains in the Bengal Basin, comprising of Lower Ganga Plain and deltaic plains of Ganga–Brahmaputra–Meghna River system, little thought was given to its possible threat in the upstream parts in the Gangetic Plains beyond Garo-Rajmahal Hills. The contamination in Bengal Basin has become one of the extensively studied issues in the world and regarded as the severest case of health hazard in the history of mankind. The researches and investigations in the Gangetic Plains during the last decade (2003–2013) revealed that the eastern half of the plains, also referred as Middle Ganga Plain (MGP), is particularly affected by contamination, jeopardising the shallow aquifer-based drinking water supply. The present paper reviews researches and investigations carried out so far in MGP by various research institutes and government departments on wide array of issues of groundwater As such as its spatio-temporal variation, mobilisation paths, water level behaviour and flow regime, configuration of contaminated and safe aquifers and their recharge mechanism. Elevated conc. of groundwater As has been observed in grey and dark grey sediments of Holocene age (Newer Alluvium) deposited in a fluvio-lacustrine environment in the floodplain of the Ganga and most of its northern tributaries from Himalayas. Older Alluvium, comprising Pleistocene brownish yellow sediment, extending as deeper aquifers in Newer Alluvium areas, is low in groundwater As. Similarities and differences on issues between the MGP and the Bengal Basin have been discussed. The researches point towards the mobilisation process as reductive dissolution of iron hydroxide coating, rich in adsorbed As, mediated by microbial processes. The area is marked with shallow water level (<8.0 m below ground) with ample monsoonal recharge. The infiltrated rainwater and percolating water from surface water bodies carry organic carbon from sediments (particularly from the clay plugs in abandoned channels), abetting microbial processes, spread of anoxic front and release of As.     

Evaluation of microelement contents in <Emphasis Type="Italic">Clethra barbinervis</Emphasis> as food for human and animals in contrasting geological areas

The young leaves of Clethra barbinervis Sieb. et Zucc, which is a deciduous tree species found in secondary forests widely in Japan, are used in spring as a local traditional food by local populations, and the bark of this plant is also preferred by sika deer, Cervus nippon. However, C. barbinervis has been known to accumulate heavy metals in its leaves. Then, we aimed to clarify the characteristics of microelement contents in C. barbinervis and to discuss the value of this species as food for humans and animals through the analysis of seasonal changes and distribution in various organs of C. barbinervis growing under two different geological conditions. We found that C. barbinervis is an accumulating and tolerant plant for Ni, Co and Mn. It accumulates Ni from serpentine soil containing Ni at high concentration, and Co and Mn from acidic soils based on crystalline schist. The seasonal variation in element concentrations in leaves indicates that the young leaves contain Cu at high concentration and that eating them in spring season may be advantageous to humans, due to the associated increase in Cu intake. The high concentrations of Cu and Zn in the bark of C. barbinervis might explain why deer prefer to eat the bark of this species.     

Lithological and hydrochemical controls on distribution and speciation of uranium in groundwaters of hard-rock granitic aquifers of Madurai District,Tamil Nadu (India)

Uranium is a radioactive element normally present in hexavalent form as U(VI) in solution and elevated levels in drinking water cause health hazards. Representative groundwater samples were collected from different litho-units in this region and were analyzed for total U and major and minor ions. Results indicate that the highest U concentration (113 µg l^?1) was found in granitic terrains of this region and about 10 % of the samples exceed the permissible limit for drinking water. Among different species of U in aqueous media, carbonate complexes [UO₂(CO₃) ₂ ^2? ] are found to be dominant. Groundwater with higher U has higher pCO₂ values, indicating weathering by bicarbonate ions resulting in preferential mobilization of U in groundwater. The major minerals uraninite and coffinite were found to be supersaturated and are likely to control the distribution of U in the study area. Nature of U in groundwater, the effects of lithology on hydrochemistry and factors controlling its distribution in hard rock aquifers of Madurai district are highlighted in this paper.     

Chemically modified biochar produced from conocarpus waste increases NO<Subscript>3</Subscript> removal from aqueous solutions

Biochar has emerged as a universal sorbent for the removal of contaminants from water and soil. However, its efficiency is lower than that of commercially available sorbents. Engineering biochar by chemical modification may improve its sorption efficiency. In this study, conocarpus green waste was chemically modified with magnesium and iron oxides and then subjected to thermal pyrolysis to produce biochar. These chemically modified biochars were tested for NO₃ removal efficiency from aqueous solutions in batch sorption isothermal and kinetic experiments. The results revealed that MgO-biochar outperformed other biochars with a maximum NO₃ sorption capacity of 45.36 mmol kg^?1 predicted by the Langmuir sorption model. The kinetics data were well described by the Type 1 pseudo-second-order model, indicating chemisorption as the dominating mechanism of NO₃ sorption onto biochars. Greater efficiency of MgO-biochar was related to its high specific surface area (391.8 m² g^?1) and formation of strong ionic complexes with NO₃. At an initial pH of 2, more than 89 % NO₃ removal efficiency was observed for all of the biochars. We conclude that chemical modification can alter the surface chemistry of biochar, thereby leading to enhanced sorption capacity compared with simple biochar.     

Residual veterinary antibiotics in pig excreta after oral administration of sulfonamides

Sulfonamides (SAs) are applied widely as feed additives in the farming of livestock and poultry. It can lead to the excretion of large amounts of SAs in manure and result in persistent environmental pollution. We evaluated the fate of four SAs, sulfamerazine (SM₁), sulfachloropyridazine (SCP), sulfadimoxine (SDM′) and sulfaquinoxaline (SQ), from oral administration to excretion in urine and feces in pigs. The four SAs were added to homemade feed to make them reach the required concentration gradient, which were 0, 50 and 100 mg/kg (low, normal and high concentrations, respectively). In different treatments, excretions of the four SAs were 35.68–86.88 %. With regard to total excretion, the order was SQ > SCP > SM₁ > SDM′ for all treatments. The concentration of SAs in the feed had significant effects on the amount of the four SAs excreted every day. The concentration of SAs in feces and in the urine for different treatments was 15.03–26.55 and 14.54–69.22 %, respectively. In each treatment, excretions of SCP, SDM′ and SQ in feces were lower than that in urine. The four SAs remained longer in urine than in feces. Excretions in urine and feces were lower if SAs were administered orally rather than by injection.     

Products of biotransformation of polycyclic aromatic hydrocarbons in fishes of the Athabasca/Slave river system,Canada

Concentrations of products of biotransformation of polycyclic aromatic hydrocarbons (PBPAH) were measured in bile of five fishes of nutritional, cultural and ecological relevance from the Athabasca/Slave river system. Samples were collected in Alberta and the Northwest Territories, Canada, during three seasons. As a measure of concentrations of PBPAHs to which fishes are exposed and to gain information on the nature and extent of potential exposures of people or piscivorous wildlife, concentrations of biotransformation products of two- and three-ringed, four-ringed and five-ringed PAHs were measured using synchronous fluorescence spectroscopy. Spatial and seasonal differences were observed with greater concentrations of PBPAHs in samples of bile of fish collected from Fort McKay as well as greater concentrations of PBPAHs in bile of fish collected during summer compared to those collected in other seasons. Overall, PBPAHs were greater in fishes of lower trophic levels and fishes more closely associated with sediments. In particular, goldeye (Hiodon alosoides), consistently contained greater concentrations of all the PBPAHs studied.     

Estimated lead (Pb) exposures for a population of urban community gardeners

Urban community gardens provide affordable, locally grown, healthy foods and many other benefits. However, urban garden soils can contain lead (Pb) that may pose risks to human health. To help evaluate these risks, we measured Pb concentrations in soil, vegetables, and chicken eggs from New York City community gardens, and we asked gardeners about vegetable consumption and time spent in the garden. We then estimated Pb intakes deterministically and probabilistically for adult gardeners, children who spend time in the garden, and adult (non-gardener) household members. Most central tendency Pb intakes were below provisional total tolerable intake (PTTI) levels. High contact intakes generally exceeded PTTIs. Probabilistic estimates showed approximately 40 % of children and 10 % of gardeners exceeding PTTIs. Children’s exposure came primarily from dust ingestion and exposure to higher Pb soil between beds. Gardeners’ Pb intakes were comparable to children’s (in µg/day) but were dominated by vegetable consumption. Adult household members ate less garden-grown produce than gardeners and had the lowest Pb intakes. Our results suggest that healthy gardening practices to reduce Pb exposure in urban community gardens should focus on encouraging cultivation of lower Pb vegetables (i.e., fruits) for adult gardeners and on covering higher Pb non-bed soils accessible to young children. However, the common practice of replacement of root-zone bed soil with clean soil (e.g., in raised beds) has many benefits and should also continue to be encouraged.