The impact of climate change on tourism in Germany,the UK and Ireland: a simulation study

We downscale the results of a global tourism simulation model at a national resolution to a regional resolution. We use this to investigate the impact of climate change on the regions of Germany, Ireland and the UK. Because of climate change, tourists from all three countries would spend more holidays in the home country. In all three countries, climate change would first reduce the number of international arrivals—as Western European international tourist demand falls—but later increase numbers—as tourism demand from increasingly rich tropical countries grows. In Ireland and the UK, the regional pattern of demand shifts is similar to the international one: tourism shifts north. In Germany, the opposite pattern is observed as the continental interior warms faster than the coast: tourism shifts south.

Temporal and spatial trends in water quality of Lake Taihu,China: analysis from a north to mid-lake transect, 1991–2011

Interpretations of state and trends in lake water quality are generally based on measurements from one or more stations that are considered representative of the response of the lake ecosystem. The objective of this study is to examine how these interpretations may be influenced by station location in a large lake. We addressed this by analyzing trends in water quality variables collected monthly from eight monitoring stations along a transect from the central lake to the north in Lake Taihu (area about 2,338 km²), China, from October 1991 to December 2011. The parameters examined included chlorophyll a (Chl a), total nitrogen (TN), and total phosphorus (TP) concentrations, and Secchi disk depth (SD). The individual variables were increasingly poorly correlated among stations along the transect from the central lake to the north, particularly for Chl a and TP. The timing of peaks in individual variables was also dependent on station location, with spectral analysis revealing a peak at annual frequency for the central lake station but absence of, or much reduced signal, at this frequency for the near-shore northern station. Percentage annual change values for each of the four variables also varied with station and indicated general improvement in water quality at northern stations, particularly for TN, but little change or decline at central lake stations. Sediment resuspension and tributary nutrient loads were considered to be responsible for some of the variability among stations. Our results indicate that temporal trends in water quality may be station specific in large lakes and that calculated whole-lake trophic status trends or responses to management actions may be specific to the station(s) selected for monitoring and analysis. These results have important implications for efficient design of monitoring programs that are intended to integrate the natural spatial variability of large lakes.     

Immobilization of mercury by pyrite (FeS2)

Elemental mercury (Hg⁰) is a metal with a number of atypical properties, which has resulted in its use in myriad anthropogenic processes. However, these same properties have also led to severe local subsurface contamination at many places where it has been used. As such, we studied the influence of various parameters on Hg(II) sorption onto pyrite (pH, time, Hg(II) concentration), a potential subsurface reactive barrier. Batch sorption studies revealed that total Hg(II) removal increases with both pH and time. X-ray absorption spectroscopy analysis showed that a transformation in the coordination environment at low pH occurred during aging over 2 weeks, to form an ordered monolayer of monodentate Hg-Cl complexes on pyrite. In column studies packed with pure quartz sand, the transport of Hg(II) was significantly retarded by the presence of a thin pyrite-sand reactive barrier, although dissolved oxygen inhibited Hg(II) sorption onto pyrite in the column.     

Ice Shelf Microbial Ecosystems in the High Arctic and Implications for Life on Snowball Earth

 The Ward Hunt Ice Shelf (83°N, 74°W) is the largest remaining section of thick (>10 m) landfast sea ice along the northern coastline of Ellesmere Island, Canada. Extensive meltwater lakes and streams occur on the surface of the ice and are colonized by photosynthetic microbial mat communities. This High Arctic cryo-ecosystem is similar in several of its physical, biological and geochemical features to the McMurdo Ice Shelf in Antarctica. The ice-mats in both polar regions are dominated by filamentous cyanobacteria but also contain diatoms, chlorophytes, flagellates, ciliates, nematodes, tardigrades and rotifers. The luxuriant Ward Hunt consortia also contain high concentrations (10⁷–10⁸ cm^–2) of viruses and heterotrophic bacteria. During periods of extensive ice cover, such as glaciations during the Proterozoic, cryotolerant mats of the type now found in these polar ice shelf ecosystems would have provided refugia for the survival, growth and evolution of a variety of organisms, including multicellular eukaryotes. Received: 30 August 1999 / Accepted in revised form: 15 December 1999     

The long-term environmental behaviour of strontium and barium released from former mine workings in the granites of the Sunart region of Scotland, UK

The concentrations of strontium and barium have been measured in water, sediment and the shells of mussels (Mytilus edulis) from a river system in the Sunart region of Scotland, UK. The aim was to establish the fate and mobility of these elements, which are slowly being released from old mine workings on the Strontian granites. Enhanced strontium (1500-2000 microg l(-1) and 250-290 microg l(-1)) and barium concentrations (316 microg l(-1) and 83 microg l(-1)) were found in the waters originating from the two mine drains studied. Both element were also found at significant levels in the river sediments taken from the vicinity of each drainage site (Sr: 225 microg g(-1) and 120-125 microg g(-1); Ba: 1380 microg g(-1) and 126-170 microg g(-1)). The data suggests that the sediments are acting as a reservoir for these group II cations from where they become distributed throughout the river system. Strontium is found to be incorporated into the shells (3.16-3.46 microg g(-1)) and pearls (3.57 microg g(-1)) of the blue mussel, located at the estuarine margin some 10 km downstream, at values close to the maximum expected (3.3% by weight of the calcium content). The study presents a view of the fate of barium and strontium in a river system over a prolonged period of time. As such it provides valuable information for studies that seek to model the impact of the accidental release of barium and strontium (including the important radionuclide 90Sr) into the environment.     

Octachlorodibenzo-p-dioxin in wood treatment materials and treated wood

The octachlorodibenzo-p-dioxin (OCDD) concentrations have been determined in aged samples of commercial pentachlorophenol (PCP), in wood protection formulations containing PCP and in wood treated with PCP as a preservative or as an anti-sapstain treatment. The concentrations of OCDD found in the various samples are within the range expected from the amount of commercial PCP initially present in the samples. In view of the known stability of OCDD the results are interpreted as indicating that the formulation, treatment and ageing processes have not led to any substantial conversion of PCP to OCDD; although one result indicates that outdoor exposure of treated samples increased the OCDD concentration by a factor of approximately 2 after $\text{3}\text{1}\text{2}$ years. Analysis of aged samples of treated wood indicate that OCDD is lost much less rapidly from the wood than PCP.     

The Missoula Valley semivolatile and volatile organic compound study: seasonal average concentrations

The city of Missoula is located in a high mountain valley (elevation 3200 ft.) in western Montana and contains one of the largest populations in the entire Rocky Mountain Region completely enclosed by mountains. During the 2000/2001 Missoula Valley Sampling Program, ambient levels of 61 semivolatile organic compounds (SVOCs) and 54 volatile organic compounds (VOCs) were originally quantified before refining the analytical program to 28 of the most prominent SVOCs and VOCs found in the Missoula Valley airshed. These compounds were measured over 24-hr periods at two locations throughout an entire year. This study provides the first, comprehensive appraisal of the levels of SVOCs and VOCs measured simultaneously throughout all four seasons at two locations in the Missoula Valley, including those levels measured during the 2000 Montana wildfire season. Generally, SVOC levels were comparable between both sides of the Missoula Valley. However, there were nearly double the amount of VOCs measured at the more urban Boyd Park site compared with the rural Frenchtown sampling site, a result of the greater number of automobiles on the eastern side of the Valley. SVOCs and VOCs were measured at their highest levels of the sampling program during the winter. Forest fire smoke samples collected during the summer of 2000 showed significant increases in SVOC phenolic compounds, including phenol, 2-methylphenol, 4-methylphenol, and 2,4-dimethylphenol. Although there were modest increases in some of the other SVOCs and VOCs measured during the fire season, none of the increases were as dramatic as the phenolics.     

(137)Cs inter-plant concentration ratios provide a predictive tool for coral atolls with distinct benefits over transfer factors

Inter-plant concentration ratios (IPCR) [Bqg(-1)(137)Cs in coral atoll tree food crops/Bqg(-1)(137)Cs in leaves of native plant species whose roots share a common soil volume] can replace transfer factors (TF) to predict (137)Cs concentration in tree food crops in a contaminated area with an aged source term. The IPCR strategy has significant benefits relative to TF strategy for such purposes in the atoll ecosystem. IPCR strategy applied to specific assessments takes advantage of the fact that tree roots naturally integrate (137)Cs over large volumes of soil. Root absorption of (137)Cs replaces large-scale, expensive soil sampling schemes to reduce variability in (137)Cs concentration due to inhomogeneous radionuclide distribution. IPCR [drinking-coconut meat (DCM)/Scaevola (SCA) and Tournefortia (TOU) leaves (native trees growing on all atoll islands)] are log-normally distributed (LND) with geometric standard deviation (GSD)=1.85. TF for DCM from Enewetak, Eneu, Rongelap and Bikini Atolls are LND with GSDs of 3.5, 3.0, 2.7, and 2.1, respectively. TF GSD for Rongelap copra coconut meat is 2.5. IPCR of Pandanus fruit to SCA and TOU leaves are LND with GSD=1.7 while TF GSD is 2.1. Because IPCR variability is much lower than TF variability, relative sampling error of an IPCR field sample mean is up 6- to 10-fold lower than that of a TF sample mean if sample sizes are small (10-20). Other IPCR advantages are that plant leaf samples are collected and processed in far less time with much less effort and cost than soil samples.