ARPA-E

About: ARPA-E is a government organization based out in Washington D.C., District of Columbia, United States. It is known for research contribution in the topics: Population & Climate change. The organization has 1161 authors who have published 1267 publications receiving 30049 citations. The organization is also known as: Advanced Research Projects Agency - Energy.

Speciation of vanadium in urban, industrial and volcanic soils by a modified Tessier method

Abstract: Vanadium (V) concentrations in industrial, urban and volcanic soils were sequentially extracted using a modified Tessier's method. The voltammetric technique was used to determine V concentrations in solutions obtained from the various extraction steps. At the reference stations, the V concentrations (sum of four individual fractions) in soils ranged from 0.72 to 0.24 g kg(-1) dry weight (d.w.) with a mean value of 0.18 g kg(-1) d.w. V concentrations in soils of the Palermo urban area ranged from 0.34 to 2.1 g kg(-1) d.w., in the Milazzo (industrial) area between 0.26 and 5.4 g kg(-1) d.w. and in the volcanic area near Mt. Etna from 0.91 to 2.9 g kg(-1) d.w. When the V concentrations around Mt. Etna were compared with those obtained at the reference stations, it was confirmed that Mt. Etna is a continuous source of V. In all the samples analyzed, the majority of V (from 94 to 100%) was detected in the fourth fraction.

Statistical Analysis of Bathing Water Quality in Puglia Region (Italy).

Abstract: Geostatistic analysis was applied to the dataset from multi-year monitoring, in the Apulian marine-coastal zone (Mediterranean Sea, Italy), on the presence and abundance of intestinal Enterococci and Escherichia coli, microbiological indicators of faecal contamination at the sea. The same faecal contamination can be considered as the main cause of pollution phenomenon under current Italian and European regulations for the bathing waters (Italian Government Decree 116/2008, European Directive 2006/7/CE). The main objective of the study is to verify, taking into the account the anthropic pressures acting on the coastal zone, the efficiency of the Apulian regional monitoring plan currently in force for the assessment of bathing waters quality, with a view to a hypothetical reduction of sample collection points.

Ecophysiological Responses to Rainfall Variability in Grassland and Forests Along a Latitudinal Gradient in Italy

Abstract: In the Mediterranean region, ecosystems are severely affected by climate variability. The Italian Peninsula is a hot spot for biodiversity thanks to heterogeneous landscape and Mediterranean, Continental, and Alpine climates hosting a broad range of plant functional types along a limited latitudinal range from 40' to 46' N. In this study we applied a comparative approach integrating descriptive statistics, time series analysis, and multivariate techniques to answer the following questions: (i) do the climatic variables affect GPP, Reco, WUE and ET to a similar extent among different sites? (ii) Does a common response pattern exist among ecosystems along a latitudinal gradient in Italy? And, finally (iii) do these ecosystems respond synchronically to meteorological conditions or does a delayed response exists? Six sites along a latitudinal, altitudinal and vegetational gradient from semi-arid (southern Italy) to a mountainous Mediterranean site (central Italy) and sub-humid wet Alpine sites (northern Italy) were considered. For each site, carbon and water fluxes and meteorological data collected during two hydrologically-contrasting years (i.e. a dry and a wet year) were analysed. Principal Component Analysis was adopted to identify temporal and spatial variations in Gross Primary Productivity (GPP), Ecosystem Respiration (Reco), Water Use Efficiency (WUE) and Evapotranspiration (ET). The model outlined differences among Mediterranean semi-arid, Mediterranean mountainous, and Alpine sites in response to contrasting precipitation regimes. GPP, Reco, WUE and ET increased up to 16, 19, 25 and 28 %, respectively in semi-arid Mediterranean sites and up to 15, 32, 15 and 11%, respectively in Alpine sites in the wet year compared to the dry year. Air temperature was revealed to be one of the most important variables affecting GPP, Reco, WUE and ET in all the study sites. While relative air humidity was more important in southern Mediterranean sites, global radiation was more significant in northern Italy. Our work suggests that a realistic prediction of the main responses of Italian forests under climate change should also take in account delayed responses due to acclimation to abiotic stress or changing environmental conditions.

High spatial resolution interpolation of monthly temperatures of Sardinia

Abstract: Interpolation of monthly averages of maximum and minimum temperatures for 1 year data on a 250 m grid by multilinear regression his presented here. The principal aim is to find a suitable parameter for interpolation of minimum temperatures in cases of nocturnal inversion. For this purpose a geostatistical parameter has been calculated and tested. It is related to the height relative to the nearest valley. The second aim is to find how the regression equation depends on the sea distance, if in a linear or non linear form and, if nonlinear, what is the best exponent. The procedure has been tested on a 1 year data set from 60 meteorological stations on Sardinia Island. The selection of parameters has been made by the forward selection method. The interpolation errors (RMSE) on independent stations (i.e. not used to calculate the regression coefficient) have been calculated by the cross-validation method using a developmental data set of size n − 1. The parameter that contains most of the variance is the height: the second one, for minimum temperatures, is the relative height. For maximum temperatures the second parameter is the sea distance, but only in summer months. The RMSE on the independent data ranges from 1.0 to 1.5 °C for minimum temperatures and from 0.5 °C (winter months) to 1.4 °C (summer months) for maximum temperatures. The effect of relative elevation in the regression is a 15% increase of the coefficient of determination. At the same time it lowers the RMSE significantly. Copyright © 2011 Royal Meteorological Society