29 research outputs found
Biomonitoring of metal deposition in northern Spain by moss analysis
The results of the first survey carried out in northern Spain to determine atmospheric deposition of metals by
analysis of terrestrial mosses, are described. Samples of different mosses, mainly Hypnum cupressiforme and
Scleropodium purum, were collected from 134 sampling sites, between 1995 and 1996. Levels of Al, As, Cr, Cu, Fe,
Hg, Ni, Pb and Zn, were determined by flame atomic absorption or atomic fluorescence spectrophotometry. Regression
analysis was used to compare the capacity of the selected moss species to accumulate the elements, and intercalibration
of accumulation in these species was carried out where necessary. Distribution maps were prepared to allow the zones
most affected by metal deposition to be identified and to relate this to known sources of contamination: electricity
power stations and other industries (e.g. Hg and Ni), edaphic contamination (e.g. Al and Cr) and road traffic (Pb).
Background levels of metals in each species were also determined for the study area
Heavy metal and nitrogen concentrations in mosses are declining across Europe whilst some âhotspotsâ remain in 2010
In recent decades, naturally growing mosses have been used successfully as biomonitors of atmospheric deposition of heavy metals and nitrogen. Since 1990, the European moss survey has been repeated at five-yearly intervals. In 2010, the lowest concentrations of metals and nitrogen in mosses were generally found in northern Europe, whereas the highest concentrations were observed in (south-)eastern Europe for metals and the central belt for nitrogen. Averaged across Europe, since 1990, the median concentration in mosses has declined the most for lead (77%), followed by vanadium (55%), cadmium (51%), chromium (43%), zinc (34%), nickel (33%), iron (27%), arsenic (21%, since 1995), mercury (14%, since 1995) and copper (11%). Between 2005 and 2010, the decline ranged from 6% for copper to 36% for lead; for nitrogen the decline was 5%. Despite the Europe-wide decline, no changes or increases have been observed between 2005 and 2010 in some (regions of) countries
A perspective on ecologically relevant plant-UV research and its practical application
Plants perceive ultraviolet-B (UV-B) radiation through the UV-B photoreceptor UV RESISTANCE LOCUS 8 (UVR8), and initiate regulatory responses via associated signalling networks, gene expression and metabolic pathways. Various regulatory adaptations to UV-B radiation enable plants to harvest information about fluctuations in UV-B irradiance and spectral composition in natural environments, and to defend themselves against UV-B exposure. Given that UVR8 is present across plant organs and tissues, knowledge of the systemic signalling involved in its activation and function throughout the plant is important for understanding the context of specific responses. Fine-scale understanding of both UV-B irradiance and perception within tissues and cells requires improved application of knowledge about UV-attenuation in leaves and canopies, warranting greater consideration when designing experiments. In this context, reciprocal crosstalk among photoreceptor-induced pathways also needs to be considered, as this appears to produce particularly complex patterns of physiological and morphological response. Through crosstalk, plant responses to UV-B radiation go beyond simply UV-protection or amelioration of damage, but may give cross-protection over a suite of environmental stressors. Overall, there is emerging knowledge showing how information captured by UVR8 is used to regulate molecular and physiological processes, although understanding of upscaling to higher levels of organisation, i.e. organisms, canopies and communities remains poor. Achieving this will require further studies using model plant species beyond Arabidopsis, and that represent a broad range of functional types. More attention should also be given to plants in natural environments in all their complexity, as such studies are needed to acquire an improved understanding of the impact of climate change in the context of plant-UV responses. Furthermore, broadening the scope of experiments into the regulation of plant-UV responses will facilitate the application of UV radiation in commercial plant production. By considering the progress made in plant-UV research, this perspective highlights prescient topics in plant-UV photobiology where future research efforts can profitably be focussed. This perspective also emphasises burgeoning interdisciplinary links that will assist in understanding of UV-B effects across organisational scales and gaps in knowledge that need to be filled so as to achieve an integrated vision of plant responses to UV-radiation.Peer reviewe
Environmental effects of stratospheric ozone depletion, UV radiation, and interactions with climate change : UNEP Environmental Effects Assessment Panel, Update 2020
This assessment by the Environmental Effects Assessment Panel (EEAP) of the United Nations Environment Programme (UNEP) provides the latest scientific update since our most recent comprehensive assessment (Photochemical and Photobiological Sciences, 2019, 18, 595-828). The interactive effects between the stratospheric ozone layer, solar ultraviolet (UV) radiation, and climate change are presented within the framework of the Montreal Protocol and the United Nations Sustainable Development Goals. We address how these global environmental changes affect the atmosphere and air quality; human health; terrestrial and aquatic ecosystems; biogeochemical cycles; and materials used in outdoor construction, solar energy technologies, and fabrics. In many cases, there is a growing influence from changes in seasonality and extreme events due to climate change. Additionally, we assess the transmission and environmental effects of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is responsible for the COVID-19 pandemic, in the context of linkages with solar UV radiation and the Montreal Protocol.Peer reviewe
Environmental effects of stratospheric ozone depletion, UV radiation, and interactions with climate change : UNEP Environmental Effects Assessment Panel, Update 2021
The Environmental Effects Assessment Panel of the Montreal Protocol under the United Nations Environment Programme evaluates effects on the environment and human health that arise from changes in the stratospheric ozone layer and concomitant variations in ultraviolet (UV) radiation at the Earth's surface. The current update is based on scientific advances that have accumulated since our last assessment (Photochem and Photobiol Sci 20(1):1-67, 2021). We also discuss how climate change affects stratospheric ozone depletion and ultraviolet radiation, and how stratospheric ozone depletion affects climate change. The resulting interlinking effects of stratospheric ozone depletion, UV radiation, and climate change are assessed in terms of air quality, carbon sinks, ecosystems, human health, and natural and synthetic materials. We further highlight potential impacts on the biosphere from extreme climate events that are occurring with increasing frequency as a consequence of climate change. These and other interactive effects are examined with respect to the benefits that the Montreal Protocol and its Amendments are providing to life on Earth by controlling the production of various substances that contribute to both stratospheric ozone depletion and climate change.Peer reviewe
Brioflora del rĂo Iregua (La Rioja, España)
Presentamos un catĂĄlogo de la brioflora del rĂo Iregua (La Rioja, España) compuesto por 123 tĂĄxones, 40 hepĂĄticas y 83 musgos. Bryum barnesii Wood in Schimp. es nuevo para España, 8 taxones mĂĄs son nuevos para el sistema IbĂ©rico, y 24 mĂĄs para la Rioja. Analizamos la riqueza especĂfica de las 60 localidades muestreadas, y las agrupamos mediante el Ăndice de afinidad de Jaccard. Discutimos los tipos de reproducciĂłn observados, la frecuencia de las especies y algunos aspectos evolutivos. Summary: The catalogue of the bryoflora of Iregua river (La Rioja, Spain), is composed of 123 taxa. Bryum barnesii is a new record for Spain, 8 taxa are new for the Iberian System, and 24 for La Rioja. Species richness of the 60 sampled localities is analysed and JaccardÂŽs affinity index used. Reproductive trends, frequency and some evolutive aspects of the collected species are discussed
Brioflora del piso de marojal de la Sierra de Cameros
Presentamos un Catålogo de Briofitos en el que recogemos 136 taxones, 100 de Musgos y 36 de Hepåticas. Son nuevas para el Catålogo Briológico de La Rioja 31 especies y 3 variedades. De ellas, 14 especies son nuevas para el Sistema Ibérico, y 7 no lo son para el Sistema Ibérico Septentrional. Se cita por segunda vez para España Mnium lycopodioides Schwaegr.; por tercera vez Zygodon forsteri (With.) Mitt.; y Saelania glaucescens (Hedw.) Broth. se cita por primera vez fuera de los Pirineos y el Montseny. El elemento corológico Circumboreal domina en la zona estudiada (59,7%), seguido del Atlåntico, Cosmopolita y Mediterråneo (17,2-15,7 y 7,4%, respectivamente). Summary: We have studied the Bryophytes of the Sierra de Cameros (La Rioja). We have collected 131 species and 5 varieties; 34 of them are new for the province; 14 species are new for the Sistema Ibérico, and 7 more ones are new for the northern area of that chain of mountains. WeŽve collected Mnium lycopodioides Schwaegr. for the second time in Spain; Zygodon forsteri (With.) Mitt. for the third time, and we enlarge the distribution area of Saelania glaucescens, only collected before in the Pirineos and Montseny. The most representative species of our area are those of circumboreal distribution (59,7%)
Weaker photosynthetic acclimation to fluctuating than to corresponding steady UVB radiation treatments in grapevines
The effects of transient increases in UVB radiation on plants are not well known; whether cumulative damage dominates or, alternately, an increase in photoprotection and recovery periods ameliorates any negative effects. We investigated photosynthetic capacity and metabolite accumulation of grapevines (Vitis vinifera Cabernet Sauvignon) in response to UVB fluctuations under four treatments: fluctuating UVB (FUV) and steady UVB radiation (SUV) at similar total biologically effective UVB dose (2.12 and 2.23 kJ mâ2 dayâ1), and their two respective no UVB controls. We found a greater decrease in stomatal conductance under SUV than FUV. There was no decrease in maximum yield of photosystem II (Fv/Fm) or its operational efficiency (ÉžPSII) under the two UVB treatments, and Fv/Fm was higher under SUV than FUV. Photosynthetic capacity was enhanced under FUV in the lightâlimited region of rapid lightâresponse curves but enhanced by SUV in the lightâsaturated region. Flavonol content was similarly increased by both UVB treatments. We conclude that, while both FUV and SUV effectively stimulate acclimation to UVB radiation at realistic doses, FUV confers weaker acclimation than SUV. This implies that recovery periods between transient increases in UVB radiation reduce UVB acclimation, compared to an equivalent dose of UVB provided continuously. Thus, caution is needed in interpreting the findings of experiments using steady UVB radiation treatments to infer effects in natural environments, as the stimulatory effect of steady UVB is greater than that of the equivalent fluctuating UVB