Thermal neutron fluence from ultra low-level γ-ray spectrometry of spoons activated during the JCO criticality accident at Tokai-mura in 1999

During the JCO-accident in Tokai-mura in 1999, the surrounding village was irradiated by an uncontrolled neutron flux. At some locations in that village, the thermal neutron flux was determined retrospectively by measurement of the very low activity of ⁵¹Cr and ⁶⁰Co in stainless-steel spoons using γ-ray spectrometry in underground laboratories. Activities determined in the HADES underground facility are presented here, together with calibrations performed using a well-defined thermal neutron flux to directly estimate the fluence of thermal neutrons independent of most assumptions. The results show measurable ⁵¹Cr in three samples and ⁶⁰Co in four samples taken from locations at distances of up to 430 m from the accident location despite the elapse of 4 half-lives of ⁵¹Cr before measurement. Effects of air transport of the samples were considered and shown to be negligible.     

The distribution of 210Pb in human bone and its impact on methods for the retrospective estimation of 222Rn exposure from in vivo measurements

It is possible to estimate radon exposure to man retrospectively by the in vivo measurement of the decay product (210)Pb, which accumulates in the bones. For in vivo methods, knowledge of the distribution of (210)Pb in the skeleton is needed to determine the optimal site for measurement, the skull or the knee. In this study the activity of (210)Pb in a variety of bone samples from 3 individuals have been measured in vitro using underground gamma-ray spectrometry. The individuals were unlikely to have had elevated intakes of Rn. These measurements give baseline data on the bone massic activity of (210)Pb. They show that the massic activity is similar for each of these people and there are similar massic activities of (210)Pb in the skull and the knee of the 2 individuals for which the skull was measured. Additionally for 2 of the individuals trabecular and cortical bone were separated and massic activities were found to be strongly correlated indicating that the (210)Pb is associated with the hydroxyapatite.     

Biosafety principles for GMOs in the context of sustainable development

If genetically modified organisms are to contribute to welfare they must be considered in the context of sustainable development. Biosafety implies considering the environmental, economic and social dimensions of sustainable development. These dimensions can be interpreted through the principles of precaution, polluter pays and public participation. In this article, these key biosafety principles are operationalised and ways of implementing them in society are discussed. A comparison is made between the principles and the present EU law for deliberate release of GMOs. It is concluded that several improvements in EU policy are necessary to ensure sustainable development really is promoted.     

Continuity and change: understanding livelihood shifts and adaptation in coastal Belize 1830–2012

This paper situates livelihood adaptations in two coastal villages within the broader context of Belize's colonial and post-colonial history and environmental processes of change. Through observations, qualitative interviews, and archival reviews, we explore the dynamics of livelihood change and analyse the diverse factors that have been influencing options and adaptation over time. The results reveal that both villages have undergone profound changes in livelihoods and productive activities on several occasions. While the villages' histories, geographies, and cultures are different, similarities in long-term trends include the transition from land-based to marine resources and the decline of small-scale agriculture. Our analysis illuminates the deep connections between local livelihoods and national as well as global political–economic processes, which favour extraction and export of natural resources throughout the period investigated, whereby resource access and market mechanisms create and constrict adaptation options for the villagers. Gradual environmental changes, such as erosion, and episodic events, such as hurricanes, have also influenced livelihood shifts and adaptations in combination with a wide range of political–economic factors. Despite the demonstrated importance of the influence of history and dimensions of political economy on contemporary adaptation options in the communities studied, the literature on climate change adaptation inadequately accounts for these factors. This paper adds new perspectives to current debates in climate change research by emphasising that longer temporal dimensions of livelihood change are important for understanding the current context for adaptation.     

Diffusive gradients in thin films,Rhizon soil moisture samplers,and indicator plants to predict the bioavailabilities of potentially toxic elements in contaminated technosols

The phytoavailabilities and potential remobilization of potentially toxic elements (PTEs) such as Zn, Pb, Cd, As, and Sb were assessed in contaminated technosols from former mining and smelting sites. The PTE concentrations in soil pore water (SPW) and diffusive gradients in thin films (DGT)-measured concentration (C _DGT) methods were used to assess the bioavailabilities of PTE and their remobilization in this study. Together with classical Chelex-100 DGT probes to measure Zn, Cd, and Pb, novel ferrihydrite-backed DGT were used for As and Sb measurements alongside with Rhizon soil moisture sampler method for SPW sampling. To assess the phytoavailabilities of PTE, a germination test with dwarf beans as a plant indicator was used for this purpose. Dwarf bean primary leaves showed high Zn concentrations in contrast to Pb and Cd which showed low phytoavailabilities. Despite As and Sb are present in high concentrations in the mine tailings, their phytoavailabilities indicate very low bioavailabilities. The amounts of Zn, Pb, Cd, As, and Sb extracted with DGT devices correlated well with the total dissolved PTE concentrations in the SPW. The highest R values were observed for Zn, followed by Cd and Pb, indicating the ability of the soil to sustain SPW concentrations, which decreased in that order. Good correlations were also observed between each of dissolved PTE concentrations in SPW, DGT-measured PTE concentrations (C _DGT), and the accumulation of PTE in dwarf bean primary leaves. It could be concluded that the use of Rhizon soil moisture samplers and DGT methods may be considered to be a good methods to predict the PTE bioavailabilities in contaminated technosols.     

Climate change,phenology, and butterfly host plant utilization

Knowledge of how species interactions are influenced by climate warming is paramount to understand current biodiversity changes. We review phenological changes of Swedish butterflies during the latest decades and explore potential climate effects on butterfly–host plant interactions using the Orange tip butterfly Anthocharis cardamines and its host plants as a model system. This butterfly has advanced its appearance dates substantially, and its mean flight date shows a positive correlation with latitude. We show that there is a large latitudinal variation in host use and that butterfly populations select plant individuals based on their flowering phenology. We conclude that A. cardamines is a phenological specialist but a host species generalist. This implies that thermal plasticity for spring development influences host utilization of the butterfly through effects on the phenological matching with its host plants. However, the host utilization strategy of A. cardamines appears to render it resilient to relatively large variation in climate.     

Estimates of AOT ozone indices from time-integrated ozone data and hourly air temperature measurements in southwest Sweden

Surface ozone concentration and surface air temperature was measured hourly at three coastal sites, four low elevation inland sites and two high elevation inland sites in southwestern Sweden. Diurnal ozone concentration range (DOR) and diurnal temperature range (DTR) were strongly correlated, both spatially and temporally, most likely because both depended on atmospheric stability. Accumulated ozone exposure above a threshold concentration of x nmol mol⁻¹ (AOTx) was estimated from time-integrated ozone concentration (as from diffusive sampling) and measures of ozone concentration variability. Two methods both estimated 24-h AOTx with high accuracy (modelling efficiencies >90% for x ≤ 40 nmol mol⁻¹). Daytime (08:00–20:00) AOTx could not be equally well estimated. Estimates were better for lower AOT thresholds. Diffusive ozone concentration sampling, combined with hourly temperature monitoring, could be a valuable complement to ozone concentration monitoring with continuous instruments.     

A synthesis of the arctic terrestrial and marine carbon cycles under pressure from a dwindling cryosphere

The current downturn of the arctic cryosphere, such as the strong loss of sea ice, melting of ice sheets and glaciers, and permafrost thaw, affects the marine and terrestrial carbon cycles in numerous interconnected ways. Nonetheless, processes in the ocean and on land have been too often considered in isolation while it has become increasingly clear that the two environments are strongly connected: Sea ice decline is one of the main causes of the rapid warming of the Arctic, and the flow of carbon from rivers into the Arctic Ocean affects marine processes and the air–sea exchange of CO₂. This review, therefore, provides an overview of the current state of knowledge of the arctic terrestrial and marine carbon cycle, connections in between, and how this complex system is affected by climate change and a declining cryosphere. Ultimately, better knowledge of biogeochemical processes combined with improved model representations of ocean–land interactions are essential to accurately predict the development of arctic ecosystems and associated climate feedbacks.