Human alteration of groundwater–surface water interactions (Sagittario River,Central Italy): implication for flow regime,contaminant fate and invertebrate response

Many rivers worldwide are undergoing severe man-induced alterations which are reflected also in changes of the degree of connectivity between surface waters and groundwater. Pollution, irrigation withdrawal, alteration of freshwater flows, road construction, surface water diversion, soil erosion in agriculture, deforestation and dam building have led to some irreversible species losses and severe changes in community composition of freshwater ecosystems. Taking into account the impact of damming and flow diversion on natural river discharge, the present study is aimed at (i) evaluating the effects of anthropogenic changes on groundwater/surface water interactions; (ii) analyzing the fate of nitrogenous pollutants at the floodplain scale; and (iii) describing the overall response of invertebrate assemblages to such changes. Hydrogeological, geochemical and isotopic data revealed short- and long-term changes in hydrology, allowing the assessment of the hydrogeological setting and the evaluation of potential contamination by nitrogen compounds. Water isotopes allowed distinguishing a shallow aquifer locally fed by zenithal recharge and river losses, and a deeper aquifer/aquitard system fed by surrounding carbonate aquifers. This system was found to retain ammonium and, through the shallow aquifer, release it in surface running waters via the hyporheic zone of the riverbed. All these factors influence river ecosystem health. As many environmental drivers entered in action offering a multiple-component artificial environment, a clear relationship between river flow alteration and benthic and hyporheic invertebrate diversity was not found, being species response driven by the combination of three main stressors: ammonium pollution, man-induced changes in river morphology and altered discharge regime.     

Analyzing CO2 emissions mitigation by technology improvement in Central and Eastern Europe

As a legacy of the centrally planned economy, the economies in transition of Central and Eastern Europe (CEE) have a unique potential to reduce their greenhouse gas emissions through the improvement in their high energy intensities. Since much of this `low-hanging fruit' in energy-efficiency improvements can be highly cost-effective, many developed countries facing difficulties in meeting their greenhouse gas (GHG) emission targets domestically are eager to find such opportunities in the CEE region. Therefore, studies analysing the potentials and costs of carbon dioxide reduction through technology improvement in the region have come into the limelight. While there are a few excellent studies in the region aimed at analysing climate change abatement potentials, they all embark on different assumptions, methodologies and boundary conditions. It is hence difficult, if not impossible, to compare and analyse the results of these studies across different authors, countries or time horizons. Consequently, the purpose of this paper is to place four leading studies on GHG mitigation through technology improvement from the CEE region into an internationally comparable framework. Four studies were selected from three countries, Poland, Hungary and Estonia, which are all the results of major national and international efforts to assess costs and potentials of GHG reduction. The paper places their assumptions, methods and final results into a framework which enables policy-makers and project designers to compare these across geographical and technological boundaries. Since other studies from around the globe have been analysed in this framework in the literature, this paper provides a vehicle for the findings of these four studies to be compared to others worldwide. In addition, the paper highlights a few areas where similar studies to be completed in the future in the region may be enhanced by incorporating features used in GHG mitigation research in other parts of the world. This revised version was published online in July 2006 with corrections to the Cover Date.     

Influence of Intra- and Interspecific Interactions on Short-term Movement of the Amphipod Corophium volutator in Varying Environmental Conditions

Movement of animals on intertidal mudflats can have profound consequences for population and community dynamics. Such movement is often influenced by biotic interactions, but the abiotic environment can also be important, affecting the strength of species’ interactions and even changing their outcome. Here, we focused on two biotic interactions and examined their effect on movement of the burrow-dwelling amphipod Corophium volutator: intraspecific interactions (specifically, the effect of conspecific density) and interspecific interactions with a competitor–predator, the mud snail Ilyanassa obsoleta (=Nassarius obsoletus). We assessed the magnitude of the temporal variation and examined the influence of pertinent abiotic variables (lunar cycle, presence of tide pools). Despite substantial temporal variation in movement levels, density of conspecifics did not influence emigration or immigration rates of C. volutator. Mud snails negatively affected immigration of C. volutator, and this was consistent across all lunar phases. However, mud snails influenced mortality and emigration of C. volutator in a contrasting way relative to lunar phases; sometimes amphipods evaded snails and survived, but at other times did not emigrate and were killed. The presence of tide pools did not change the nature or strength of the snail–amphipod interaction. Our results further clarify the complex interactions between C. volutator and I. obsoleta and suggest that resources on the mudflat are sufficient to sustain high densities of amphipods in a density-independent manner. Further, they highlight the importance of considering multiple environmental variables when examining interspecific interactions.     

Socioeconomic vulnerability and electric power restoration timelines in Florida: the case of Hurricane Irma

Large-scale damage to the power infrastructure from hurricanes and high-wind events can have devastating ripple effects on infrastructure, the broader economy, households, communities, and regions. Using Hurricane Irma’s impact on Florida as a case study, we examined: (1) differences in electric power outages and restoration rates between urban and rural counties; (2) the duration of electric power outages in counties exposed to tropical storm force winds versus hurricane Category 1 force winds; and (3) the relationship between the duration of power outage and socioeconomic vulnerability. We used power outage data for the period September 9, 2017–September 29, 2017. At the peak of the power outages following Hurricane Irma, over 36% of all accounts in Florida were without electricity. We found that the rural counties, predominantly served by rural electric cooperatives and municipally owned utilities, experienced longer power outages and much slower and uneven restoration times. Results of three spatial lag models show that large percentages of customers served by rural electric cooperatives and municipally owned utilities were a strong predictor of the duration of extended power outages. There was also a strong positive association across all three models between power outage duration and urban/rural county designation. Finally, there is positive spatial dependence between power outages and several social vulnerability indicators. Three socioeconomic variables found to be statistically significant highlight three different aspects of vulnerability to power outages: minority groups, population with sensory, physical and mental disability, and economic vulnerability expressed as unemployment rate. The findings from our study have broader planning and policy relevance beyond our case study area, and highlight the need for additional research to deepen our understanding of how power restoration after hurricanes contributes to and is impacted by the socioeconomic vulnerabilities of communities.     

Toxic metals in a highly urbanized industry-impacted estuary (Bahia Blanca Estuary,Argentina): spatio-temporal analysis based on GIS

Cadmium, chromium, nickel, and lead were evaluated in the particulate fraction at one of the most industrialized estuaries at the Southwestern Atlantic Ocean, through Geographic Information System (GIS). Concentrations were analyzed at 21 stations during 2008–2010. The highest metal concentrations (Cd: 8,9; Cr: 256,49; Ni: 27,02; Pb: 78,43 µg g^??1 d. w.) were recorded at the stations located near industrial and urban discharges situated along the estuary. In addition, Pb presented a different seasonal and spatial behavior in comparison with Cd, Cr and Ni. Winter and spring presented the higher concentrations of Pb, and the inner stations presented the higher values. The estuary is considered a moderate to strongly polluted and significantly polluted according to the Index of geoaccumulation (I_geo) and the Enrichment Factor of Cd, respectively. The Multidimensional Scaling plot showed three groups of stations: the inner, associated to low levels of metals (G1), middle stations (G2) with intermediate levels and the outer (G3) with the highest ones. In addition, this work reveals the usefulness of the GIS-mapping techniques in the distribution of pollutants along an estuarine environment and the environmental quality assessment of estuarine systems.     

Metals in tidal flats colonized by microbial mats within a South-American estuary (Argentina)

In this study, we measured the concentrations of metals (Cd, Cu, Pb, Ni, Cr, Zn, Hg, Mn, and Fe) and assessed the characteristics of tidal flats (grain size and organic matter content) in sediments and their overlying microbial mats fractions to evaluate the anthropogenic impact within the Bahía Blanca Estuary (BBE). Puerto Rosales (PR) and Almirante Brown (AB), located in the middle and inner zone of the estuary, respectively, were used as sampling sites. Sediments were composed mainly of silt–clay in AB, whereas first fine-grained particles were coarser in depth in PR. Regarding the concentration of metals in both fractions, we found differences between sites: There were higher concentrations of overall metals in AB relative to PR. In addition, higher concentrations of Cu were recorded in the first centimeters of AB tidal flats, whereas higher concentration of Cd were recorded in microbial mats of PR. Considering that the grain size was similar between sites, these results are consistent with the high concentration of organic matter found in AB, probably because this site is close to a former municipal dump and sewage discharges. Also, the higher Cd content found in PR site would highlight both the influence of untreated urban discharges and port anthropogenic activities. In conclusion, this study allowed identifying high values of some metals in the presence of microbial mats in the BBE, thus suggesting a possible interaction between both, at least for metals like Cu or Cd.     

Analysis and farmers’ perception of climate change in the Kashmir Valley,India

Theoretical and Applied Climatology - Analysis of climatic variables is important for the detection and attribution of climate change trends and has received considerable attention from researchers...     

Kinetics of the reactions of Cl atoms with 2-buten-1-ol, 2-methyl-2-propen-1-ol, and 3-methyl-2-buten-1-ol as a function of temperature

The reactions of three structurally similar unsaturated alcohols, 2-buten-1-ol (crotyl alcohol), 2-methyl-2-propen-1-ol (MPO221) and 3-methyl-2-buten-1-ol (MBO321) with Cl atoms, have been investigated for the first time, using a 400 l Teflon reaction chamber coupled with gas chromatograph-coupled with flame-ionization detection (GC-FID). The experiments were performed at atmospheric pressure and at temperatures between 255 and 298 K, in air or nitrogen as the bath gas. The obtained kinetic data were used to derive the Arrhenius expressions , , (in units of cm³ molecule⁻¹ s⁻¹). Finally, atmospheric lifetimes of those unsaturated alcohols with respect to OH, NO₃, O₃ and Cl have been calculated.     

Forecasting the impact of climate on food systems: Model testing and model linkage

This paper discusses the importance of testing models which may be used to forecast the impact of climate on society. Model testing using sensitivity analysis and validation techniques is illustrated with two models: (1) the YIELD model which simulates the impact of climate on crop yields of several major crops, and (2) the International Futures Simulation model which can be used to simulate the impact of crop yield changes on the world food system. The problems of linking such models to each other are also discussed.