Interaction of temperature and an environmental stressor: Moina macrocopa responds with increased body size,increased lifespan,and increased offspring numbers slightly above its temperature optimum

For organisms, temperature is one of the most important environmental factors and gains increasing importance due to global warming, since increasing temperatures may pose organisms close to their environmental tolerance limits and, thus, they may become more vulnerable to environmental stressors. We analyzed the temperature-dependence of the water-soluble antioxidant capacity of the cladoceran Moina macrocopa and evaluated its life trait variables with temperature (15, 20, 25, 30 °C) and humic substance (HS) concentrations (0, 0.18, 0.36, 0.90, 1.79 mM DOC) as stressors. Temperatures below and above the apparent optimum (20 °C) reduced the antioxidative capacity. Additions of HSs increased body length, but decreased mean lifespan at 15 and 20 °C. There was no clear HS-effect on offspring numbers at 15, 20, and 30 °C. At 25 °C with increasing HS-concentration, lifespan was extended and offspring numbers increased tremendously, reaching 250% of the control. Although the applied HS preparation possesses estrogenic and antiandrogenic activities, a xenohormone mechanism does not seem plausible for the reproductive increase, because comparable effects did not occur at other temperatures. A more convincing explanation appears to be the mitohormesis hypothesis which states that a certain increase of reactive oxygen production leads to improved health and longevity and, with Moina, also to increased offspring numbers. Our results suggest that at least with the eurythermic M. macrocopa, a temperature above the optimum can be beneficial for several life trait variables, even when combined with a chemical stressor. Temperatures approximately 10 °C above its optimum appear to adversely affect the lifespan and reproduction of M. macrocopa. This indicates that this cladoceran species seems to be able to utilize temperature as an ecological resource in a range slightly above its thermal optimum.     

Future land use and land cover in Southern Amazonia and resulting greenhouse gas emissions from agricultural soils

Regional Environmental Change - The calculation of robust estimates of future greenhouse gas emissions due to agriculture is essential to support the framing of the Brazilian climate change...     

Defining Chlorophyll-a Reference Conditions in European Lakes

The concept of “reference conditions” describes the benchmark against which current conditions are compared when assessing the status of water bodies. In this paper we focus on the establishment of reference conditions for European lakes according to a phytoplankton biomass indicator—the concentration of chlorophyll-a. A mostly spatial approach (selection of existing lakes with no or minor human impact) was used to set the reference conditions for chlorophyll-a values, supplemented by historical data, paleolimnological investigations and modelling. The work resulted in definition of reference conditions and the boundary between “high” and “good” status for 15 main lake types and five ecoregions of Europe: Alpine, Atlantic, Central/Baltic, Mediterranean, and Northern. Additionally, empirical models were developed for estimating site-specific reference chlorophyll-a concentrations from a set of potential predictor variables. The results were recently formulated into the EU legislation, marking the first attempt in international water policy to move from chemical quality standards to ecological quality targets.     

Venice and its lagoon fin de siecle

Regional Environmental Change - This study presents a reconstruction of basin scale long-term annual surface mass balance (SMB) estimates for 91 glaciers (≥ 1 km2) of Chandra basin in...     

The coalitional politics of the European Union’s environmental forest policy: Biodiversity conservation,timber legality,and climate protection

European forest policymaking is shaped by progressing European integration, yet with notable ideological divisions and diverging interests among countries. This paper focuses on the coalitional politics of key environmental forest issues: biodiversity conservation, timber legality, and climate protection policy. Combining the Advocacy Coalition Framework and the Shifting Coalition Theory, and informed by more than 186 key informant interviews and 73 policy documents spanning a 20-year timeframe, we examine the evolution of coalitional forest politics in Europe. We find that the basic line-up has remained stable: an environmental coalition supporting EU environmental forest policy integration and a forest sector coalition mostly opposing it. Still, strategic alliances across these coalitions have occurred for specific policy issues which have resulted in a gradual establishment of an EU environmental forest policy. We conclude with discussion of our findings and provide suggestions for further research.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01644-5.     

AhR-mediated and antiestrogenic activity of humic substances

Humic substances (HS) were for decades regarded as inert in the ecosystems with respect to their possible toxicity. However, HS have been recently shown to elicit various adverse effects generally attributed to xenobiotics. In our study, we used MVLN and H4IIE-luc cell lines stably transfected with luciferase gene under control of estrogen receptor (ER) and Ah receptor (AhR; receptor connected with so-called dioxin-like toxicity) for assessment of anti/estrogenic and AhR-mediated effects of 12 commercially available humic substances. Out of those, five humic acids were shown to induce AhR-mediated activity with relative potencies related to TCDD 2.6 x 10(-8)-7.4 x 10(-8). Organic extracts of HS solutions also elicited high activities what means that lipophilic molecules are responsible for a great part of effect. However, relatively high activity remaining in extracted solution suggests also presence of polar AhR-agonists. Contribution of persistent organic compounds to the observed effects was ruled out by H(2)SO(4) treatment. Eight out of twelve HS elicited significant antiestrogenic effects with IC(50) ranging from 40 to 164 mg l(-1). The possible explanations of the antiestrogenic effect include sorption of 17-beta-estradiol (E2) on HS, changes in membrane permeability for E2 or another specific mechanism.     

PCDD/F and dioxin-like PCB in human blood and milk from German mothers

Blood samples of pregnant women aged between 19 and 42 years at the time they gave birth and milk samples from the same women following delivery were collected between September 2000 and January 2003 from 169 participants living in an industrialized area of Germany (Duisburg birth cohort study). All samples were analyzed for their content of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) as well as dioxin-like and indicator polychlorinated biphenyls (PCB). Levels of WHO-TEq were in the range of 4.34-97.3 pg/g(lipid base) (median: 26.37, arithmetic mean: 28.36) for blood, or 3.01-78.7 pg/g(lipid base) (median: 26.40, arithmetic mean: 27.27) for milk, respectively. The four congeners 12378-PeCDD, 23478-PeCDF, 33'44'5-PeCB (# 126) and 233'44'5-HxCB (# 156) contribute the main share to total WHO-TEq. The contribution of PCDD/F in relation to PCB to total WHO-TEq was 60:40% in blood and 52:48% in milk. Good correlations of the contaminant levels in lipid base between both matrices were found. The distribution between blood and milk depends on the molecular weight of the substances. Higher chlorinated PCDD/F- and PCB-congeners were found in 2-4-fold higher concentrations in blood in relation to milk and the concentrations of lower chlorinated PCB-congeners were up to 2-fold higher in milk in relation to blood. The body burden of PCDD/F and PCB increases with age and decreases over the total nursing period. Women who had lived outside highly industrialized countries showed lower concentrations of PCDD/F and PCB. In some cases, elevated levels of PCB were observed when the women had previously lived in Eastern Europe for a long time. In comparison with recent data, the decline in human PCDD/F and PCB levels observed during the nineties seems to have stopped. The individual exposures of the infants due to breastfeeding within the first 18 months were calculated to be from 4.4 to 318 ng WHO-TEq (median: 106, arithmetic mean: 118). The actual mean daily exposure of a breastfed infant can be estimated to 131 pg WHO-TEq/kg(body weight).     

Mercury in compact fluorescent lamps (CFLs): European legislation introduces an avoidable analytical bias

European legislation has set a limit of 5 mg Hg per compact fluorescent lamp (CFL). Compliance with this regulation is tested with a method given in a European law from 2002 (“EU method”). According to the EU method, the arc tube has to be placed inside a fume cupboard and cut into segments. These pieces are collected and washed with HNO₃, which is finally analyzed for Hg. In this study, we investigated the losses of Hg via the gas phase, which are ignored by the EU method, using a semiquantitative radiochemical neutron activation analysis (RNAA) technique developed at the TRIGA Mark II reactor in Vienna (Austria). Depending on the product, the losses range as high as approximately 2 % at 20 °C. At higher ambient temperatures (hot summer days), the losses may increase by a factor of 4. Quality products generally suffer lower emission via the gas phase than cheap products, which is probably due to amalgam or other techniques that retain the Hg from broken CFLs. In any case, the EU method introduces a small but avoidable systematic error into the analysis and, in contrast to recommended practices, underestimates the Hg content of the CFL in question. Having technical alternatives at hand, we urge European lawmakers to adjust the law accordingly.     

Influence of ship emissions on air quality and input of contaminants in southern Alaska National Parks and Wilderness Areas during the 2006 tourist season

The impact of ship emissions on air quality in Alaska National Parks and Wilderness Areas was investigated using the Weather Research and Forecasting model inline coupled with chemistry (WRF/Chem). The visibility and deposition of atmospheric contaminants was analyzed for the length of the 2006 tourist season. WRF/Chem reproduced the meteorological situation well. It seems to have captured the temporal behavior of aerosol concentrations when compared with the few data available. Air quality follows certain predetermined patterns associated with local meteorological conditions and ship emissions. Ship emissions have maximum impacts in Prince William Sound where topography and decaying lows trap pollutants. Along sea-lanes and adjacent coastal areas, NO_x, SO₂, O₃, PAN, HNO₃, and PM_2.5 increase up to 650 pptv, 325 pptv, 900 pptv, 18 pptv, 10 pptv, and 100 ng m^?3. Some of these increases are significant (95% confidence). Enhanced particulate matter concentrations from ship emissions reduce visibility up to 30% in Prince William Sound and 5–25% along sea-lanes.