Heavy metals and nitrogen in mosses: spatial patterns in 2010/2011 and long-term temporal trends in Europe

Naturally-occurring mosses have been sampled across Europe to monitor the deposition of heavy metals and nitrogen from the air. This survey has been repeated at five-yearly intervals since 1990 for heavy metals and since 2005 for nitrogen. In 2010/2011, mosses were collected at ca. 4,500 sites in 25 countries for heavy metals and ca. 2,400 sites in 15 countries for nitrogen. In general, the lowest concentrations in mosses were found in northern Europe for both heavy metals and nitrogen. The highest concentrations of heavy metals were often observed in south-eastern Europe, whereas the highest concentrations of nitrogen were found in parts of western and central Europe. Europe-wide the concentration of lead (77% decline), vanadium (57%), iron (52%) and cadmium (51%) has declined the most since 1990, whereas the concentration of copper has declined the least (11% decline). Since 1995, the concentration of arsenic and mercury has declined by 26% and 23% respectively. The nitrogen concentration in mosses has hardly changed since 2005

Impacts of elevated atmospheric ozone on peatland below-ground DOC characteristics

Rising concentrations of tropospheric ozone are having detrimental impacts on the growth of crop and forest species and some studies have reported inhibition of the allocation of carbon below ground. The effects of ozone on peatland ecosystems have received relatively little attention, despite their importance within the global carbon cycle. During this study, cores from a Welsh minerotrophic fen and ombrotrophic bog were exposed to four ambient/ elevated ozone concentration regimes representing current and predicted 2050 profiles. A large and significant reduction in the concentration of porewater dissolved organic carbon (DOC) was recorded in the fen cores exposed to the elevated ozone concentrations (up to −55%), with a concurrent shift to a higher molecularweight of the remaining soil carbon. No effects of ozone on DOC concentrations or characteristics were recorded for the bog cores. The data suggest higher ozone sensitivity of plants growing in the fen-type peatland, that the impacts on the vegetation may affect soil carbon characteristics through a reduction in root exudates and that theremay have been a shift in the source of substrate DOC for microbial consumption from vegetation exudates to native soil carbon. Theremay also have been a direct effect of ozone molecules reacting with soil organic matter after being transported into the soil through the aerenchyma tissue of the overlying vegetation. These qualitative changes in the soil carbon in response to elevated ozone may have important implications for carbon cycling in peatland ecosystems, and therefore climate change

Racial Preferences in Online Dating across European Countries

Knowledge about how race governs partner selection has been predominantly studied in the United States, yet it is unclear whether these results can be generalized to nations with different racial and immigration patterns. Using a large-scale sample of online daters in nine European countries, we engage in the first cross-national analysis of race-related partner preferences and examine the link between contextual factors and ethnic selectivity. We provide a unique test of contact, conflict, and in-group identification theories. We show that individuals uniformly prefer to date same-race partners and that there is a hierarchy of preferences both among natives and minority groups. Notable country differences are also found. Europeans living in countries with a large foreign-born population have an increased preference for minority groups. The ethnically heterogeneous Swiss population displays the strongest preference for minorities, with the more homogenous Poland, Spain, and Italy, the least. Anti-immigrant attitudes are related to stronger in-group preferences among natives. Unexpectedly, non-Arabic minority daters belonging to large-size communities have strong preferences for Europeans. The results have implications for immigrant integration policies and demonstrate that Internet dating allows efficient selection by racial divisions, perpetuating country-specific racial inequalitie

Species-specific responses to ozone and drought in six deciduous trees

Saplings of alder (Alnus glutinosa), birch (Betula pendula), hazel (Corylus avellana), beech (Fagus sylvatica), ash (Fraxinus excelsior) and oak (Quercus robur) were exposed to five episodic ozone regimes in solardomes, with treatment means between 16 and 72 ppb. All trees were kept fully watered for the first five weeks of exposure, after which half the trees continued to be well-watered, whereas the other half were subjected to a moderate drought and received approximately 45% of the amount of water. Species-specific reductions in growth in response to both ozone and drought were found, which could result in reduced potential carbon sequestration in future ozone climates. In well watered conditions the ozone treatments resulted in total biomass reductions for oak (18%), alder (16%), beech (15%), ash (14%), birch (14%) and hazel (7%) in the 72 ppb compared to the 32 ppb treatment. For beech there was a reduction in growth in response to ozone in the well watered treatment, but an increase in growth in response to ozone in the drought treatment, assumed to result from changes in hormonal signalling. For alder, in addition to a decrease in root biomass there was reduced biomass of root nodules with high compared to low ozone for both drought treated and well-watered trees. There was also a large reduction in the biomass of nodules from drought trees compared to well-watered. It is therefore possible that changes in the nitrogen dynamics of alder could occur due to reduced nodulation in both drought and elevated ozone conditions

Ozone pollution affects flower numbers and timing in a simulated BAP priority calcareous grassland community

Mesocosms representing the BAP Priority habitat ‘Calcareous Grassland’ were exposed to eight ozone profiles for twelve-weeks in two consecutive years. Half of the mesocosms received a reduced watering regime during the exposure periods. Numbers and timing of flowering in the second exposure period were related to ozone concentration and phytotoxic ozone dose (accumulated stomatal flux). For Lotus corniculatus, ozone accelerated the timing of the maximum number of flowers. An increase in mean ozone concentration from 30 ppb to 70 ppb corresponded with an advance in the timing of maximum flowering by six days. A significant reduction in flower numbers with increasing ozone was found for Campanula rotundifolia and Scabiosa columbaria and the relationship with ozone was stronger for those that were well-watered than for those with reduced watering. These changes in flowering timing and numbers could have large ecological impacts, affecting plant pollination and the food supply of nectar feeding insects

Ozone pollution: a hidden threat to food security

This article summarises current knowledge on the effects of ozone on crop production. It includes maps showing the predicted effects of ozone on wheat yield in Europe 2000 and 2020, and describes the results of a study investigating the potential effects of ozone on UK crop propduction in 2008 (a typical current year) and 2006 (a growing season likely to happen more freuently in the future)

Family Formation Trajectories in Romania, the Russian Federation and France: Towards the Second Demographic Transition?

This study examines family formation trajectories as a manifestation of the second demographic transition (SDT) in three countries, comparing and contrasting two post-socialist countries (Romania and the Russian Federation) with France as benchmark country advanced in the SDT. By examining combined partnership and fertility sequences and transcending the mainly descriptive nature of trajectory-based studies, the current study expands our knowledge by including key explanatory factors, such as cohort, country, and educational level. Pooled data from the Gender and Generations Survey (N = 30,197) is used to engage in sequence, optimal matching (OM), cluster and multinomial logistic regression analysis. Post- Communist cohorts are significantly more likely to engage in long-term cohabitation, childbearing within cohabitation or lone parenthood. Educational level operates differently across countries, with the highly educated in Romania and the Russian Federation less likely to follow certain de-standardized paths. Non-marital cohabitation with children is associated with lower education in all countries. Strong differences emerge between the shape and stages of the SDT in Romania and Russia, with Russians having a higher probability to experience childbearing within cohabitation, opposed to Romanians who follow childless marriage patterns or adopt postponement and singlehood. The three countries differ in their advancement in the SDT and factors shaping partnering and childbearing choices. We conclude that although the SDT remains a useful construct, it needs to be supplemented with more nuanced contextual accounts of socio-economic conditions

Ozone – the persistent menace: interactions with the N cycle and climate change

Tropospheric ozone is involved in a complex web of interactions with other atmospheric gases and particles, and through ecosystem interactions with the N-cycle and climate change. Ozone itself is a greenhouse gas, causing warming, and reductions in biomass and carbon sequestration caused by ozone provide a further indirect warming effect. Ozone also has cooling effects, however, for example, through impacts on aerosols and diffuse radiation. Ecosystems are both a source of ozone precursors (especially of hydrocarbons, but also nitrogen oxides), and a sink through deposition processes. The interactions with vegetation, atmospheric chemistry and aerosols are complex, and only partially understood. Levels and patterns of global exposure to ozone may change dramatically over the next 50 years, impacting global warming, air quality, global food production and ecosystem function