138 research outputs found
OPEN NETWORK FOR LOCAL SELF SUSTAINABILITY, BOOSTING BIOREGIONAL DEVELOPMENT THROUGH AN OPEN DATA SHARING SYSTEM
Abstract. The paper presents an online geodatabase currently under development. Its name is Open NETwork for Local Self Sustainability and the website address is www.oloss.net.The goal of this platform is to publish and share information about production and consumption chain oriented towards the use of locally available resources. To this end, it provides an open standard of supply chains georeferenced representation, and the ability to georefer data generally used in the context of life cycle analysis of products and services. This standard has the purpose of representing production and consumption chains in the form of Impact Geographies (IGs). This database may provide public administration centers, research centers, NGOs, planners and designers with information useful to develop projects geared towards the optimal use of local resources, consistent with the bioregional development paradigm (Sale, 1985) (Scudo, 2016). The bioregional approach promotes trans-scalar regional supply and demand chains where food and energy are grown, produced, sold and consumed within a certain territorial unit.</p
Climate control on sulphate and nitrate concentrations in alpine streams of Northern Italy along a nitrogen saturation gradient
International audienceThe role of meteorology, hydrology and atmospheric deposition on the temporal pattern of SO4 and NO3 concentrations was investigated for three streams draining alpine catchments in Northern Italy. The study sites lie on a gradient of atmospheric fluxes of SO4 and NO3 (from about 50 to 80 meq m?2 y?1, and from 40 to 90 meq m?2 y?1, respectively). As a consequence of the increasing N input, the three catchments are also representative of aggrading levels of N saturation. Different methods of statistical analysis were applied to monthly data for the period 1997?2005 to identify which variables (temperature, precipitation, hydrology, SO4 and NO3 deposition) were the main predictors of water chemistry and its change in time. Hydrological changes and snow cover proved to be the main confounding factors in the response to atmospheric deposition in the River Masino catchment. Its particular characteristics (small catchment area, rapid flushing during runoff and thin soil cover) meant that this site responded without a significant delay to SO4 deposition decrease. It also showed a clear seasonal pattern of NO3 concentration, in response to hydrology and biological uptake in the growing season. The selected driving variables failed to model the water chemistry at the other study sites. Nevertheless, temperature, especially extreme values, turned out to be important in both SO4 and NO3 export from the catchments. This result might be largely explained by the effect of warm periods on temperature-dependent processes such as mineralization, nitrification and S desorption. Our findings suggest that surface waters in the alpine area will be extremely sensitive to a climate warming scenario: higher temperatures and increasing frequency of drought could exacerbate the effects of high chronic N deposition
On the classification of OADP varieties
The main purpose of this paper is to show that OADP varieties stand at an
important crossroad of various main streets in different disciplines like
projective geometry, birational geometry and algebra. This is a good reason for
studying and classifying them. Main specific results are: (a) the
classification of all OADP surfaces (regardless to their smoothness); (b) the
classification of a relevant class of normal OADP varieties of any dimension,
which includes interesting examples like lagrangian grassmannians. Following
[PR], the equivalence of the classification in (b) with the one of
quadro-quadric Cremona transformations and of complex, unitary, cubic Jordan
algebras are explained.Comment: 13 pages. Dedicated to Fabrizio Catanese on the occasion of his 60th
birthday. To appear in a special issue of Science in China Series A:
Mathematic
Results from the Italian participation in the International Co-operative Programme on Assessment and Monitoring of Acidification of Rivers and Lakes (ICP Waters)
This paper describes the research activity carried out by the Istituto Italiano di Idrobiologia of the CNR, on behalf of the Ministero dell'Ambiente, Servizio Inquinamento Atmosferico e Acustico, in the context of the Italian participation in the International Cooperative Programme on Assessment and Monitoring of Acidification of Rivers and Lakes (ICP Waters). Atmospheric deposition chemistry shows that nitrate increased and sulphate decreased in the 70's and 80's, while acidity started to decrease in the early 90's. The studied rivers and lakes show variations in sulphate and nitrate in agreement with those of atmospheric deposition. Alkalinity is mainly determined by watershed geo-lithology and is always present in the studied lakes and streams; the lowest values of 0-10 ÎŒeq l-1 are measured in the high altitude Lake Paione Superiore, which however shows an increasing trend of alkalinity and pH
A modelling assessment of acidification and recovery of European surface waters
The increase in emission of sulphur oxides and nitrogen (both oxidised and reduced forms) since the mid-1800s caused a severe decline in pH and ANC in acid-sensitive surface waters across Europe. Since c.1980, these emissions have declined and trends towards recovery from acidification have been widely observed in time-series of water chemistry data. In this paper, the MAGIC model was applied to 10 regions (the SMART model to one) in Europe to address the question of future recovery under the most recently agreed emission protocols (the 1999 Gothenburg Protocol). The models were calibrated using best available data and driven using S and N deposition sequences for Europe derived from EMEP data. The wide extent and the severity of water acidification in 1980 in many regions were illustrated by model simulations which showed significant deterioration in ANC away from the pre-acidification conditions. The simulations also captured the recovery to 2000 in response to the existing emission reductions. Predictions to 2016 indicated further significant recovery towards pre-acidification chemistry in all regions except Central England (S Pennines), S Alps, S Norway and S Sweden. In these areas it is clear that further emission reductions will be required and that the recovery of surface waters will take several decades as soils slowly replenish their depleted base cation pools. Chemical recovery may not, however, ensure biological recovery and further reductions may also be required to enable these waters to achieve the "good ecological status" as required by the EU Water Framework Directive
Assessing recovery from acidification of European surface waters in the year 2010: evaluation of projections made with the MAGIC model in 1995
In 1999 we used the MAGIC (Model of Acidification of Groundwater In Catchments) model to project acidification of acid-sensitive European surface waters in the year 2010, given implementation of the Gothenburg Protocol to the Convention on Long-Range Transboundary Air Pollution (LRTAP). A total of 202 sites in 10 regions in Europe were studied. These forecasts can now be compared with measurements for the year 2010, to give a âground truthâ evaluation of the model. The prerequisite for this test is that the actual sulfur and nitrogen deposition decreased from 1995 to 2010 by the same amount as that used to drive the model forecasts; this was largely the case for sulfur, but less so for nitrogen, and the simulated surface water [NO3â] reflected this difference. For most of the sites, predicted surface water recovery from acidification for the year 2010 is very close to the actual recovery observed from measured data, as recovery is predominantly driven by reductions in sulfur deposition. Overall these results show that MAGIC successfully predicts future water chemistry given known changes in acid deposition
Data Descriptor : Long-term chloride concentrations in North American and European freshwater lakes
Anthropogenic sources of chloride in a lake catchment, including road salt, fertilizer, and wastewater, can elevate the chloride concentration in freshwater lakes above background levels. Rising chloride concentrations can impact lake ecology and ecosystem services such as fisheries and the use of lakes as drinking water sources. To analyze the spatial extent and magnitude of increasing chloride concentrations in freshwater lakes, we amassed a database of 529 lakes in Europe and North America that had greater than or equal to ten years of chloride data. For each lake, we calculated climate statistics of mean annual total precipitation and mean monthly air temperatures from gridded global datasets. We also quantified land cover metrics, including road density and impervious surface, in buffer zones of 100 to 1,500m surrounding the perimeter of each lake. This database represents the largest global collection of lake chloride data. We hope that long-term water quality measurements in areas outside Europe and North America can be added to the database as they become available in the future.Peer reviewe
Alpine bogs of southern Spain show human-induced environmental change superimposed on long-term natural variations
Recent studies have proved that high elevation environments, especially remote wetlands, are exceptional ecological sensors of global change. For example, European glaciers have retreated during the 20th century while the Sierra Nevada National Park in southern Spain witnessed the first complete disappearance of modern glaciers in Europe. Given that the effects of climatic fluctuations on local ecosystems are complex in these sensitive alpine areas, it is crucial to identify their long-term natural trends, ecological thresholds, and responses to human impact. In this study, the geochemical records from two adjacent alpine bogs in the protected Sierra Nevada National Park reveal different sensitivities and long-term environmental responses, despite similar natural forcings, such as solar radiation and the North Atlantic Oscillation, during the late Holocene. After the Industrial Revolution both bogs registered an independent, abrupt and enhanced response to the anthropogenic forcing, at the same time that the last glaciers disappeared. The different response recorded at each site suggests that the National Park and land managers of similar regions need to consider landscape and environmental evolution in addition to changing climate to fully understand implications of climate and human influence.This study was supported by the project P11-RNM 7332 of the âJunta de AndalucĂaâ, the projects CGL2013-47038-R and CGL2015-67130-C2-1-R of the âMinisterio de EconomĂa y Competitividad of Spain and Fondo Europeo de Desarrollo Regional FEDERâ and the research group RNM0190 and RNM309 (Junta de AndalucĂa). A.G.-A. was also supported by a Marie Curie Intra-European Fellowship of the 7th Framework Programme for Research, Technological Development and Demonstration of the European Commission (NAOSIPUK. Grant Number: PIEF-GA-2012-623027) and by a RamĂłn y Cajal Fellowship RYC-2015-18966 of the Spanish Government (Ministerio de EconomĂa y Competividad). J.L.T. was also supported by a Small Research Grant by the Carnegie Trust for the Universities of Scotland and hosted the NAOSIPUK project (PIEF-GA-2012-623027). M. J. R-R acknowledges the PhD funding provided by ConsejerĂa de EconomĂa, InnovaciĂłn, Ciencia y Empleo de la Junta de AndalucĂa (P11-RNM 7332)
Spin temperatures and covering factors for HI 21-cm absorption in damped Lyman-alpha systems
We investigate the practice of assigning high spin temperatures to damped
Lyman-alpha absorption systems (DLAs) not detected in HI 21-cm absorption. In
particular, Kanekar & Chengaulr (2003) have attributed the mix of 21-cm
detections and non-detections in low redshift (z<2.04) DLAs to a mix of spin
temperatures, while the non-detections at high redshift were attributed to high
spin temperatures. Below z=0.9, where some of the DLA host galaxy morphologies
are known, we find that 21-cm absorption is normally detected towards large
radio sources when the absorber is known to be associated with a large
intermediate (spiral) galaxy. Furthermore, at these redshifts, only one of the
six 21-cm non-detections has an optical identification and these DLAs tend to
lie along the sight-lines to the largest background radio continuum sources.
For these and many of the high redshift DLAs occulting large radio continua, we
therefore expect covering factors of less than the assumed/estimated value of
unity. This would have the effect of introducing a range of spin temperatures
considerably narrower than the current range of >9000 K, while still supporting
the hypothesis that the high redshift DLA sample comprises a larger proportion
of compact galaxies than the low redshift sample.Comment: Submitted to MNRAS, 11 pages, 6 figure
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