Carbon fluxes from coarse woody debris in southern taiga forests of the Valdai Upland

Studies in three typical forest biotopes of the Valdai Upland were performed to evaluate the stocks and surface area of coarse woody debris from spruce and birch (in linear transects), its colonization by xylotrophic fungi (during reconnaissance surveys), and CO₂ emission (by a chamber method). The stock and surface area were minimum in a paludal birch forest (46.4 m³/ha and 960 m²/ha) and maximum in a decay area of spruce forest (256.1 m³/ha and 3761 m²/ha, respectively). The assemblages of wood-decay fungi had a composition typically found in southern taiga forests. The total CO₂ flux varied from 145 kg C-CO₂/ha per year in the paludal birch forest to 462 kg C-CO₂/ha per year in small herb–green moss spruce forest. It is concluded that air temperature is an informative predictor of seasonal C-CO₂ flux rate from coarse woody debris.     

Dietary overlap among ruminants,geese, and lemmings of Wrangel Island in summer

Trends in the dynamics of herbivore community related to trophic competition in summer have been analyzed on Wrangel Island. The results show that the trophic spectra overlap considerably, resources are partitioned on the principle “weak competitors after strong competitors,” and community dynamics in the absence of extermination depend on specific competitive advantages related to the width of food spectrum. We conclude that the dynamics of this insular community prior to the establishment of nature reserve on the island have been determined by human activities, as well as the structure of arctic herbivore communities in general.     

Recovering Food Commons in Post Industrial Europe: Cooperation Networks in Organic Food Provisioning in Catalonia and Norway

This paper explores food commoning through an ethnographic case study in Catalonia as our primary site while the Norwegian case is juxtaposed as a comparison, two agriculturally and economically different European countries. The ethnography analyses cooperation networks between organic food producers’ and consumers’ involving different nodes of community gardening initiatives, self-employed growers, local farmers and all of them under a unique cooperative integrating a community economy. The result it is a myriad of exchange practices ranging from reciprocity and barter to market exchange without intermediaries through on-line platforms. Along these exchanges different options of currency intervene giving rise to novel social and cooperative relations. Similar initiatives in Norway show less variation and are less experimental regarding forms of payment but share similarities in relation to material articulations, concerns and forms of alternative practice. Although these novel forms do not represent a complete break from the more standardized supply chains, and hence from the oppositions/contradictions of production and consumption, the participants see themselves as contributing to a more general process of de-commodification of food. We explore the extent to which the meaning and moral values are mutually constituted in relation to socioeconomic exchanges and environmental caring that each person experiences based on different forms of cooperation and reciprocity. Food, we suggest, is more than a commodity on the market that we may influence through our role as consumers. It is a significant focal point connecting our lives to those of others that articulates one’s relations to society in a political manner.     

Think globally,act locally: neighbourhood pollution and the future of the earth

Each year governments and industry around the globe spend billions of dollars in search of treatments and cures for diseases that shorten lives, which often means gadgets, implants, radiation and pills. These “cures”, do not get to the root of the problem. Perhaps it is time for us to adjust our thinking to be more proactive instead of reactive in public health. Perhaps we need to consider confronting environmental pollution of air, soil and water at a local level. As the Physicians for Social Responsibility point out, we should be “preventing what we cannot cure”. One such preventive measure is ensuring that our communities, including our poor inner-city neighbourhoods, enjoy a clean environment. We challenge local and national policy-makers to respond to the global call and to take action to address environmental toxins; to take local action to ameliorate the pollution of the air, water and soil in so many of our nation’s neighbourhoods. A person’s neighbourhood, and the proximity of dangerous environmental contaminants within it, is a powerful predictor of how long s/he will live. While situations like the poisoning of the water in Flint, Michigan have gotten some attention, they are generally treated as the exception rather than a reflection of real environmental hazards that exist in the west. Moreover we wonder why more endemic issues of neighbourhood environmental contamination that shorten human lives are not a priority for local action or that it is not linked to disproportionate production of greenhouse gases that cause climate change/warming/chaos.     

Improving photostability and efficiency of polymeric luminescent solar concentrators by PMMA/MgO nanohybrid coatings

MgO nanocrystals were synthesized and doped with different concentrations in poly(methylmethacrylate) (PMMA) to prepare hybrid organic-inorganic coatings based on polymer nanohybrid thin films. The nanoparticles were found to be spherical with 62 nm diameter as determined by X-ray diffraction (XRD) and atomic force microscope (AFM). The coatings were characterized by spectroscopic tools such as optical absorption, transmission and fluorescence spectroscopy. The prepared nanohybrid films were spin-coated on cost-effective luminescent PMMA substrates doped with highly efficient luminescent dyes luminescent solar concentrators (LSCs). The outdoor photostability tests demonstrated enhanced protection against UVA radiation for coated LSCs compared to bare LSC substrates. The current–voltage characteristics of commercially produced LSC prototypes showed that the poor UV response of monocrystalline silicon solar cell can be improved by for LSCs coated by PMMA/MgO nanohybrid films which act as luminescent down shifting layer (LDSL).     

Plant species richness of riverbed elevations—the Pripyat river valley case study

Flora of the still unchanged or slightly modified floodplains is particularly valuable. Such are the natural, periodically flooded riparian ecosystems within the Mid-Pripyat river valley in Belarus. Distinctive elements of that area are ‘periodic islands’, which arise from the most elevated parts of the riverbed during flooding and have a specific microtopography. The aim of the research was to recognize floristic composition and ecological conditions of the ‘islands.’ Noted plants were mainly photophilous, by clearly varied in soil moisture, acidity and fertility requirements.     

Adaptive properties of the dandelion (Taraxacum officinale Wigg. s.l.) under conditions of air pollution by motor vehicle exhausts

Microcalorimetric, gasometric, and nuclear magnetic resonance (NMR) methods have been used to evaluate heat production, gas exchange, and root membrane permeability in dandelion of different morphological forms from populations exposed to different levels of air pollution. The results show that these forms differ in the level of energy metabolism and that the form with a higher metabolic level (T. off. f. dahlstedtii) is more tolerant of air pollution with motor vehicle exhausts.     

Impact of urban anthropogenic pollution on seed production,morphological and biochemical characteristics of chamomile,Matricaria chamomila L.

It has been shown that the growth of technogenic dust pollution is accompanied by the accumulation of heavy metals in soil and plant phytomass, compared to the control, and that the morphometric and reproductive characteristics of Matricaria chamomila are most sensitive to the impact of these pollutants. The response of plants is manifested in increased variation in morphological characters, mobilization of compensatory protective biochemical mechanisms, and production of more viable seed progeny.     

Seasonal ecophysiology of an endangered coastal species,the yellow-horned poppy (Glaucium flavum Crantz)

Glaucium flavum Crantz. is a short-lived perennial herb distributed in coastal zones from the Black Sea to southern, western and north-western Europe. Despite its diminishing area of distribution and potential pharmacological value, little is known about the ecophysiological features of this coastal species. We investigated the photosynthetic performance of G. flavum by measuring gas exchange, chlorophyll fluorescence, photosynthetic pigment concentration and leaf water content over the space of a year in a coastal habitat of SW Spain. We also measured the variation in total concentrations of nitrogen, phosphorus, sulphur, potassium, calcium and magnesium, in the leaves and soil, throughout the study period. G. flavum showed a high resistance to summer drought conditions which appeared to be due to the high degree of stomatal control. The potential photochemical efficiency of photosystem II showed minimum values during the winter, indicating that low temperatures can produce negative effects within the photosynthetic apparatus. However, the marked decline in net photosynthesis during the winter seems to be mainly related to a loss of metabolic activity. Although leaf nutrient concentrations were, in general, within the normal ranges, phosphorus availability seems to be limited by the high calcium concentrations detected in the soil of the study site. Our study points out the efficiency of the different physiological adaptations of this rare and endangered coastal species in coping with the strong seasonal variability of the Mediterranean climate.