Enrichments of the mantle sources beneath the Southern Volcanic Zone (Andes) by fluids and melts derived from abraded upper continental crust

Mafic basaltic-andesitic volcanic rocks from the Andean Southern Volcanic Zone (SVZ) exhibit a northward increase in crustal components in primitive arc magmas from the Central through the Transitional and Northern SVZ segments. New elemental and Sr–Nd-high-precision Pb isotope data from the Quaternary arc volcanic centres of Maipo (NSVZ) and Infernillo and Laguna del Maule (TSVZ) are argued to reflect mainly their mantle source and its melting. For the C-T-NSVZ, we identify two types of source enrichment: one, represented by Antuco in CSVZ, but also present northward along the arc, was dominated by fluids which enriched a pre-metasomatic South Atlantic depleted MORB mantle type asthenosphere. The second enrichment was by melts having the characteristics of upper continental crust (UCC), distinctly different from Chile trench sediments. We suggest that granitic rocks entered the source mantle by means of subduction erosion in response to the northward increasingly strong coupling of the converging plates. Both types of enrichment had the same Pb isotope composition in the TSVZ with no significant component derived from the subducting oceanic crust. Pb–Sr–Nd isotopes indicate a major crustal compositional change at the southern end of the NSVZ. Modelling suggests addition of around 2 % UCC for Infernillo and 5 % for Maipo.     

Securing the Neoliberal City: Discourses of Creativity and Priority Neighborhoods in Toronto,Canada

This paper examines the convergence between the discourse of the creative city and the discourse on priority neighborhoods within urban policy imaginaries in Toronto, Canada. In particular, it examines the development of a number of arts programs targeted at low-income neighborhoods in the city. The twin objectives of these programs are to (a) foster creative and entrepreneurial subjectivities among “at-risk” youth, and (b) reduce the risk of violence that is presumed to be associated with youths living in poor neighborhoods. The paper analyzes how these two discourses are intertwined in a neoliberal politics devoted to enhancing regional quality-of-life competitiveness and to branding Toronto as an attractive creative-class destination. [Key words: creative city, poverty, low-income neighborhoods, neoliberalism, Toronto.]     

Monitoring heat losses using Landsat ETM+ thermal infrared data — a case study at Kuju fumarolic area in Japan

To monitor heat losses using Landsat 7 thermal infrared data from 2002 to 2010 within the active fumarolic region of Kuju volcano in Japan, we used the Stefan-Boltzmann equation for radiative heat flux (RHF) estimation. Heat discharge rate (HDR) was calculated by using the relationship coefficient of RHF and HDR, obtained from two previous studies. The highest total RHF was found to be about 57.7 MW in 2002 and the lowest was about 21.1 MW in 2010. We found the highest HDR, of about 384.5 MW, in 2002 and the lowest, of about 140.8 MW, in 2010. The RHF anomalous areas were showing a declining trend during our study period. The relationship between the land surface temperature (LST) above ambient and RHF was, as expected, in a strong correlation for each result during our study period. Overall, our study was able to delineate the declining trend of heat losses that supports a previous study of similar declining trend of HDR using steam maximum diameter method from the active fumarolic region of Kuju volcano.     

Induction of Metamorphosis in the Asian Shore Crab <Emphasis Type="Italic">Hemigrapsus sanguineus</Emphasis>: Effects of Biofilms and Substratum Texture

Since its initial invasion in the late 1980s, the Asian shore crab Hemigrapsus sanguineus has spread over 650 km along the Atlantic Coast of the United States. Larvae of this species can live in the water column for over 3 weeks, which provides ample time for transport to new locations. Previous research on the settlement and metamorphosis of H. sanguineus showed that postlarvae (megalopae) accelerate metamorphosis in response to very specific water-soluble cues. However, the response to substratum cues appears to be much broader. The experiments presented here were designed to test the metamorphic response to biofilms and substratum texture. We found that nylon mesh with pore size of 100 and 1,000 μm had a greater effect on mean time to metamorphosis than 10 and 2,000 μm mesh. Results also showed a positive response to natural rock substrata, and this response was most pronounced when megalopae were exposed to substrata with rough texture. In addition, we found that a combination of a textured surface and a natural biofilm accelerated metamorphosis more than either an abiotic substratum or a smooth surface covered with natural biofilm. A final experiment compared the effect of textural cues to that of a water-soluble cue found in exudate from adult H. sanguineus. Results indicated that both types of cue-induced metamorphosis to the same extent.     

Monitoring Heat Losses Using Landsat ETM + Thermal Infrared Data: a Case Study in Unzen Geothermal Field, Kyushu, Japan

The Unzen geothermal field, our study area, is situated in the Shimabara Peninsula of Kyushu Island in Japan and is an area of active fumaroles.. Our prime objectives were (1) to estimate radiative heat flux (RHF), (2) to calculate approximately the heat discharge rate (HDR) using the relationship of RHF with the total heat loss derived from two geothermal field studies, and (3) finally, to monitor RHF as well as HDR in our study area using seven sets of Landsat 7 ETM + images from 2000 to 2009. We used the normalized differential vegetation index (NDVI) method for spectral emissivity estimation, the mono-window algorithm for land surface temperature (LST), and the Stefan–Boltzmann equation analyzing those satellite TIR images for RHF. We estimated that the maximum RHF was about 251 W/m² in 2005 and minimum was about 27 W/m² in 2001. The highest total RHF was about 39.1 MW in 2005 and lowest was about 12 MW in 2001 in our study region. We discovered that the estimated RHF was about 15.7 % of HDR from our studies. We applied this percentage to estimate HDR in Unzen geothermal area. The monitoring results showed a single fold trend of HDR from 2000 to 2009 with highest about 252 MW in 2005 and lowest about 78 MW in 2001. In conclusion, TIR remote sensing is thought as the best option for monitoring heat losses from fumaroles with high efficiency and low cost.     

Trace elements in tissues of cetacean species rarely stranded along the Israeli Mediterranean coast

In this paper we present the concentrations of Hg, Cd, Se, Pb, Cu, Mn, Zn and Fe in organs of 6 non-common specimens of cetaceans that were stranded along the Israeli Mediterranean coast (IMC), during 2002–2010: two fin whales, one minke whale, one Cuvier’s beaked whale, one rough-toothed dolphin, and one Risso’s dolphin. Most of the specimens were calves stranded by accident. Concentrations of Hg and Cd were low in tissues of the baleen whales and higher in the toothed whales, with maximum concentrations of 1067 mg kg⁻¹ Hg in the liver of the Risso’s dolphin and 29 mg kg⁻¹ Cd in the kidney of the Cuvier’s beaked whale. As far as we are aware, this is the first report of trace elements in baleen whales in the Eastern Mediterranean, and the first report of trace elements in minke whale and rough-toothed dolphin in the Mediterranean.     

The social construction of the service sector: institutional structures and labour market outcomes

I argue that the characterisation of the lower end of the service sector as innately poorly paid, casualised and unorganised confuses cause and effect. It describes the effects of an institutional vacuum that allows this sector to suffer severe wage competition, which results in low wages and poor working conditions. There is nothing innate in the lower end of the service sector that makes these jobs poorly paid except the lack of institutions, such as unions and the state, structuring this segment of the labour market. Pay and working conditions vary within the sector and between specific locations, and depend on institutions, or the lack of institutions, to structure the local labour market. I use the case of hotel employees and restaurant employees in Las Vegas to show that not only can high union densities affect wages and other measurable benefits but a strategically unionised labour market also can transform the structure of the labour market itself.     

Annually laminated sediments date the drainage of the Ancylus Lake and early Holocene shoreline displacement in central Finland

Three independent varve (annually laminated) chronologies, verified by paleomagnetic dating, were used in the present biostratigraphical study to investigate the history of the Baltic basin in central Finland. Diatom analyses of the studied sediment sequences show the transition from the Ancylus Lake taxa to small-lake diatoms at the isolation boundary. These three varved profiles provide the following data and information on early Holocene events in central Finland: (i) a shoreline displacement curve between the deglaciation at ca. 9000 BC and ca. 7000 BC, (ii) relative emergence of the land area between 116 and 96 m above the present day sea level, which proceeded at a rate of ca. 2.6 cm year⁻¹, (iii) the calendar year age for the Lake Ancylus at ca. 8250–8200 BC, and (iv) the calendar year age for the Betula/Pinus pollen zone boundary (ca. 8100 BC) and Alnus arrival (ca. 7100 BC).     

Holocene records of carbon and hydrogen isotope ratios of organic matter in annually laminated sediments of Lake Korttajärvi, central Finland

An 11.6 m long continuous succession of annually laminated sediments from Lake Korttajärvi in central Finland was investigated for the isotopic composition of carbon and hydrogen in organic matter. The sequence covers a time period of 9590 years, and the varve chronology has been thoroughly described in earlier studies. From 7100 to 4400 BC the lake was part of the Ancient Lake Päijänne, but in 4400 BC it became separated and formed the present independent lake system. Two organic fractions were investigated. One fraction obtained by HCl-treatment was analyzed for δ¹³C and another HCl-HF-digested organic fraction was analyzed for both δ¹³C and δD. The isotopic data were compared to atomic C/N ratios, carbon contents, diatom-inferred pH values and other environmental parameters. The diatom-inferred pH values and organic carbon contents provide evidence for a long-term change towards more acidic conditions and lower productivity in Lake Korttajärvi. The inferred pH values decrease from 7.0 to 6.1, followed by a slight increase during the last millennia. Variations in pH are accompanied by an increase in the δ¹³C_HCl-HF values of organic matter from ?31.6 to $-29.2\permilleAn 11.6 m long continuous succession of annually laminated sediments from Lake Korttaj?rvi in central Finland was investigated for the isotopic composition of carbon and hydrogen in organic matter. The sequence covers a time period of 9590 years, and the varve chronology has been thoroughly described in earlier studies. From 7100 to 4400 BC the lake was part of the Ancient Lake P?ij?nne, but in 4400 BC it became separated and formed the present independent lake system. Two organic fractions were investigated. One fraction obtained by HCl-treatment was analyzed for δ¹³C and another HCl-HF-digested organic fraction was analyzed for both δ¹³C and δD. The isotopic data were compared to atomic C/N ratios, carbon contents, diatom-inferred pH values and other environmental parameters. The diatom-inferred pH values and organic carbon contents provide evidence for a long-term change towards more acidic conditions and lower productivity in Lake Korttaj?rvi. The inferred pH values decrease from 7.0 to 6.1, followed by a slight increase during the last millennia. Variations in pH are accompanied by an increase in the δ¹³C_HCl-HF values of organic matter from −31.6 to , followed by a subtle decrease to . The changes in pH and δ¹³C_HCl-HF are closely related (r = − 0.91, P < 0.01), and apparently reflect changing environmental conditions in the lake and in its catchment area. δD values show a marked shift to higher values during the early Holocene, which may be partly related to a climatic amelioration leading to the Holocene Climatic Optimum in 6000–2500 BC. The Medieval Warm Period in AD 980–1250 is associated with a local maximum in δD, lending support for a significant warming during that time.