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The COVID-19 pandemic is a global crisis emanating both from a virus (SARS-CoV-2) and from the drastic actions to contain it. Here, we reflect on the immediate responses of most world powers amid the pandemic chaos: totalitarian surveillance and nationalist isolation. Drawing on published literature, we consider measures such as wildlife-use bans, lockdowns and travel restrictions, along with their reverberations for people, economies and the planet. Our synthesis highlights significant shortfalls of applying command-and-control tactics in emergencies. For one, heavy-handed bans risk enormous unintended consequences and tend to fail if they lack legitimacy or clash with people’s values. Furthermore, reactive and myopic strategies typically view the pandemic as a stand-alone crisis, rather than unravelling the complex interplay of nature-society interactions through which zoonotic diseases originate. A return to adaptive management approaches that recognise root causes and foster socio-ecological resilience will be essential to improve human and planetary health and mitigate future pandemics.  相似文献   
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The toxic effects of heavy metals pose a significant threat to the productivity and stability of forest ecosystems. Changes in the agrochemical properties of polluted forest soils due to global climate changes can increase the bioavailability of previously immobilized heavy metals. To test this hypothesis, we studied the effects of short-term shock exposure to ZnSO4 (50, 150, 300 μM) or CuSO4 (2.5, 5, 10 μM) in hydroculture on 4- to 6-week-old seedlings of Scots pine (Pinus sylvestris L.) with well-developed root systems. The effects of the excess heavy metals on mineral nutrients and the functioning of low-molecular-weight antioxidants and glutathione in protecting plants from oxidative damage were studied. Even short-term exposure to exogenous metals led to their rapid accumulation in the root system and their subsequent transport to aboveground organs. An increase in the 4-hydroxyalkenals content in seedling needles exposed to excess Cu led to an increase in the content of proanthocyanidins and catechins, which act as scavengers of reactive oxygen species. The impact of both metals led to the rapid development of mineral nutrient imbalances in the seedlings, which were most pronounced in the presence of excess Zn. Exposure to excess Zn led to a disruption in the translocation of Fe and a decrease in the Fe content in the needles. The most dramatic consequence of Zn exposure was the development of Mn deficiency in the roots, which was the likely cause of the inhibition of phenolic compound synthesis. A deficiency in phenolic compounds can have serious environmental consequences for pine populations that are at risk of contamination by Zn and Cu salts.

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Generation of alum sludge (AS) at drinking water treatment plants represents an environmental liability and adds to the cost of water purification. Consequently, this study explored the feasibility of using low and high carbon containing alum sludge from two water treatment plants to synthesize zeolite LTA. The hypothesis was that zeolite LTA synthesis was dependant upon alum sludge source and that a range of strategies may be required to optimize zeolite crystallinity. Zeolite characteristics such as morphology, phase composition, crystallinity, and particle size distribution were recorded. “One pot” hydrothermal synthesis of precursor gel with molar composition 4.2Na2O:Al2O3:1.2SiO2:168H2O at 80°C for 3 hr resulted in 25 and 46 wt.% zeolite LTA from high and low carbonaceous sludge, respectively. Prior to hydrothermal reaction stage it was discovered that ageing of the gel, addition of zeolite LTA seeds, ultrasonic treatment and calcination all promoted zeolite LTA formation. Calcination of the alum sludge at 700°C for 2 hr before hydrothermal synthesis resulted in particle size reduction and the highest amount of crystalline zeolite LTA: 79 wt.% from low carbon sludge and 65 wt.% from high carbon sludge. Notably, the zeolite crystallinity reported in this study was the higher than previous studies on this topic. The outlined approach may allow value adding of alum waste and produce a commodity which could be used locally by the water treatment plant as a water softener.  相似文献   
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In many animals, males bear bright ornamental color patches that may signal both the direct and indirect benefits that a female might accrue from mating with him. Here we test whether male coloration in the Pipevine Swallowtail butterfly, Battus philenor, predicts two potential direct benefits for females: brief copulation duration and the quantity of materials the male passes to the female during mating. In this species, males have a bright iridescent blue field on the dorsal hindwing surface, while females have little or no dorsal iridescence. Females preferentially mate with males who display a bright and highly chromatic blue field on their dorsal hindwing. In this study, we show that the chroma of the blue field on the male dorsal hindwing and male body size (forewing length) significantly predict the mass of material or spermatophore that a male forms within the female’s copulatory sac during mating. We also found that spermatophore mass correlated negatively with copulation duration, but that color variables did not significantly predict this potential direct benefit. These results suggest that females may enhance the material benefits they receive during mating by mating with males based on the coloration of their dorsal hindwing.  相似文献   
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Sediment samples from the upper Danube River in Germany have previously been characterized as ecotoxicologically hazardous and contaminants in these sediments may contribute to the observed decline of fish populations in this river section. For the investigation of sediment toxicity there is a need for development, standardization and implementation of in vivo test systems using vertebrates. Therefore, the main objective of this study was to apply and evaluate a recently established fish gill EROD assay as a biomarker in sediment toxicity assessment by using extracts of well characterised sediment samples from the upper Danube River. This to our knowledge is the first application of this novel assay to sediment extracts. Sediments from four different sites along the upper Danube River were Soxhlet-extracted with acetone and dissolved in DMSO. Three-spined sticklebacks (Gasterosteus aculeatus L.) were exposed for 48 h to various concentrations of the extracts, to the positive control beta-naphthoflavone or to the solvent. Measurements of EROD activity in gill filaments and liver microsomes followed the exposure. Concentration-dependent induction of EROD in both gill and liver was found for all sediment extracts. The highest EROD-inducing potency was determined for extracts of sediments from the sites "Opfinger See" and "Sigmaringen" and the EROD activities in gill and liver correlated well. The results from the gill and liver assays were in accordance with in vitro results of previous investigations. The EROD activities measured in the present study corresponded with the concentrations of PAHs, PCBs and PCDD/Fs in the sediment samples derived in a previous study. The sticklebacks in this study were in the reproductive phase and a stronger EROD induction was obtained in the females than in the males. Implementation of the EROD assay in testing of sediment extracts gave highly reliable results which make this assay an ecotoxicologically relevant method for assessment of contamination with Ah receptor agonists in sediments.  相似文献   
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Environmental Science and Pollution Research - The research paper is aimed to modify the human health impact assessment of Cr in soils. The current article presents the input of several critical...  相似文献   
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