Socioeconomic development and vulnerability to land degradation in Italy

In recent years, the surface area affected by land degradation (LD) has significantly increased in southern European regions where the socioeconomic development has been proposed as a basic factor underlying the degree of vulnerability to LD. This paper investigates the correlation between several socioeconomic indicators and the level of vulnerability to LD in Italy, expressed as changes (1990–2000) in a composite index of land vulnerability (ΔLVI). The analysis was carried out over 784 local districts. The impact of per capita value added, agricultural intensity, industrial and tourism concentration, and urban growth was separately tested on ΔLVI. Results indicate that a lower district value added, crop intensification, irrigation, and the level of land vulnerability to degradation are strongly associated with the increasing level of land vulnerability over time, highlighting the role of the socioeconomic development as a main process underlying LD. In this framework, spatially equitable sustainable development may represent the effective strategy to mitigate the detrimental effects of economic growth and regional disparities on Mediterranean LD.     

Wildfire seasonality and land use: when do wildfires prefer to burn?

Because of the increasing anthropogenic fire activity, understanding the role of land-use in shaping wildfire regimes has become a major concern. In the last decade, an increasing number of studies have been carried out on the relationship between land-use and wildfire patterns, in order to identify land-use types where fire behaves selectively, showing a marked preference (or avoidance) in terms of fire incidence. By contrast, the temporal aspects of the relationship between landuse types and wildfire occurrence have received far less attention. The aim of this paper is, thus, to analyze the temporal patterns of fire occurrence in Sardinia (Italy) during the period 2000–2006 to identify land-use types where wildfires occur earlier or later than expected from a random null model. The study highlighted a close relationship between the timing of fire occurrence and land-cover that is primarily governed by two complementary processes: climatic factors that act indirectly on the timing of wildfires determining the spatial distribution of land-use types, and human population and human pressure that directly influence fire ignition. From a practical viewpoint, understanding the temporal trends of wildfires within the different land-use classes can be an effective decision-support tool for fire agencies in managing fire risk and for producing provisional models of fire behavior under changing climatic scenarios and evolving landscapes.     

Techniques for the stabilization and assessment of treated copper-, chromium-, and arsenic-contaminated soil

Remediation mainly based on excavation and burial of the contaminated soil is impractical with regard to the large numbers of sites identified as being in need of remediation. Therefore, alternative methods are needed for brownfield remediation. This study was conducted to assess a chemical stabilization procedure of CCA-contaminated soil using iron (Fe)-containing blaster sand (BS) or oxygen-scarfing granulate (OSG). The stabilization technique was assessed with regard to the feasibility of mixing ameliorants at an industrial scale and the efficiency of the stabilization under different redox conditions. The stability was investigated under natural conditions in 1-m3 lysimeters in a field experiment, and the effect of redox conditions was assessed in a laboratory experiment (10 L). The treatments with high additions of ameliorant (8% and 17%) were more successful in both the laboratory and field experiments, even though there was enough Fe on a stochiometric basis even at the lowest addition rates (0.1% and 1%). The particle size of the Fe and the mixing influenced the stabilization efficiency. The development of anaerobic conditions, simulated by water saturation, increases the fraction of arsenic (AsIII) and, consequently, As mobility. The use of high concentrations of OSG under aerobic conditions increased the concentrations of nickel (Ni) and copper (Cu) in the pore water. However, under anaerobic conditions, it decreased the As leaching compared with the untreated soil, and Ni and Cu leaching was not critical. The final destination of the treated soil should govern the amendment choice, that is, an OSG concentration of approximately 10% may be suitable if the soil is to be landfilled under anaerobic conditions. Alternatively, the soil mixed with 1% BS could be kept under aerobic conditions in a landfill cover or in situ at a brownfield site. In addition, the treatment with BS appeared to produce better effects in the long term than treatment with OSG.     

Speciation of Cr and its leachability in coal by-products from spanish coal combustion plants

This study evaluates the behaviour of total Cr and Cr (VI) during coal combustion in two Spanish power stations. The content and distribution of Cr in the feed coal and combustion wastes was determined and the Cr contents were normalized using enrichment factor indexes. The speciation of Cr in the fly ash fractions from the different hoppers of the electrostatic precipitators was established and the possibility that the Cr (VI) might lixiviate when ashes are disposed of at landfill sites was assessed. Differences in the distribution and behavior of Cr in the two power stations were observed. According to European directive 1999/31/CEE, soluble Cr(VI) in the fly ashes studied would be unlikely to pose an environmental or health risk when the ash is disposed of.     

Composition and source apportionment of dust fall around a natural lake

The aim of this study was to determine the source apportionment of dust fall around Lake Chini, Malaysia. Samples were collected monthly between December 2012 and March2013 at seven sampling stations located around Lake Chini. The samples were filtered to separate the dissolved and undissolved solids. The ionic compositions(NO-3, SO2-4, Cl-and NH+4) were determined using ion chromatography(IC) while major elements(K, Na, Ca and Mg) and trace metals(Zn, Fe, Al, Ni, Mn, Cr, Pb and Cd) were determined using inductively coupled plasma mass spectrometry(ICP-MS). The results showed that the average concentration of total solids around Lake Chini was 93.49 ± 16.16 mg/(m2·day). SO2-4, Na and Zn dominated the dissolved portion of the dust fall. The enrichment factors(EF) revealed that the source of the trace metals and major elements in the rain water was anthropogenic, except for Fe. Hierarchical agglomerative cluster analysis(HACA) classified the seven monitoring stations and 16 variables into five groups and three groups respectively. A coupled receptor model, principal component analysis multiple linear regression(PCA-MLR), revealed that the sources of dust fall in Lake Chini were dominated by agricultural and biomass burning(42%),followed by the earth's crust(28%), sea spray(16%) and a mixture of soil dust and vehicle emissions(14%).     

The influence of light exposure,water quality and vegetation on the removal of sulfonamides and tetracyclines: A laboratory-scale study

The effect of aquatic vegetation (Spyrogira sp. and Zannichellia palustris), light exposure and water quality (secondary-treated wastewater vs. ultrapure water) on the removal efficiency of six antibiotics (sulfonamides and tetracyclines) is studied in laboratory-scale reactors. After 20 d of treatment, 3–59% of sulfonamides were eliminated in the reactors exposed to light. Removal was about 10% in unplanted reactors in darkness. The elimination of tetracycline (TC) and oxytetracycline (OTC) ranged between 83% and 97% in both planted and unplanted reactors. However, in dark unplanted reactors, OTC was largely removed (88%) while only 15% of TC was eliminated. These results suggest that TC was mainly removed by photodegradation whereas biodegradation or hydrolysis process seems to be significant processes for OTC. Sulfonamides were mainly eliminated by biodegradation or indirect photodegradation processes. Pseudo-first order kinetics removal rates ranged from 0.003 and 0.007 d^?1 for Sulfamethazine and TC in the covered control reactors to 0.13 and 0.21 d^?1 for TC and OTC in the uncovered control reactors, with half-lives from 3 to 350 d. A TC photodegradation product was tentatively identified in uncovered reactors. This study highlights the important role played by light exposure in the elimination of antibiotics in polishing ponds.     

Tissue localisation of tetra- and pentabromodiphenyl ether congeners (BDE-47, -85 and -99) in perinatal and adult C57BL mice

The distribution of polybrominated diphenyl ether (PBDE) congeners was followed in C57BL mice. The animals were subjected to whole-body autoradiography using (14)C-labelled 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), 2,2',3,4,4'-pentabromodiphenyl ether (BDE-85) and 2,2',4,4',5-pentabromodiphenyl ether (BDE-99). Labelled BDE-85 and -99 were also used in quantitative studies on milk transfer and tissue concentrations during the neonatal period (12-15 days post partum), by use of liquid scintillation technique. The results show that in adult mice the studied PBDEs were effectively taken up, retained in fatty tissues and concentrated in some specific organs, i.e. the liver, adrenal cortex, ovary, lung and (initially) the brain. At longer post-injection time, the concentration in most tissues was considerably lower, and radioactivity was mainly found in fat depots and the liver. No significant difference in distribution between the three studied congeners was observed. Following maternal exposure, the foetal uptake was limited. On the other hand, during lactation a considerable fraction of the dose (about 20% of the studied penta-BDEs) given to the dam was transferred to the offspring. As in several cases the presently observed organ accumulation corresponds with earlier reports on PBDE effects in the same organs, the present results should be taken into consideration in the risk assessment of this compound group.     

Occurrence of a crinotoxin and hemagglutinin in the skin mucus of the moray eel Lycodontis nudivomer

The tropical Indo-Pacific moray eel Lycodontis nudivomer possesses a mucous skin secretion which shows hemolytic, toxic and hemagglutinating activities. The active components were extracted from the mucous secretion with 0.02 M phosphate buffer (pH 7.5) and purified by DEAE-cellulose and Sephadex G-200 column chromatography. The component(s) responsible for the hemolytic-toxic activities differ(s) from that (those) causing the hemagglutinating activity. The hemolysin was unstable in the presence of heat, acidic and alkaline media, and several organic solvents. It was undialyzable throught a cellophane membrane, and showed an absorption maxium at 280 nm in the phosphate buffer (pH 7.5). The hemolytic activity was completely lost when treated with trypsin, indicating that the hemolysin is a protein. Histochemical examination on the epidermis of L. nudivomer revealed the presence of clubbed peculiar cells, in addition to common mucous cells, which we speculate produced the hemolytic-toxic component(s). Eight other species of morays were found to possess clubbed peculiar cells similar to those of L. nudivomer in their epidermis. There are marked differences, however, in the abundance of these cells among these muraenids.