152 research outputs found
Ethyl biodiesels derived from non-edible oils within the biorefinery concept - Pilot scale production & engine emissions
Procedures and operating conditions optimized in laboratory scale for the production of ethyl biodiesels from non-edible vegetable oils (NEVOs) were successfully transferred at pilot scale, with implementation of separation and purification stages. The three NEVOs candidates are Balanites aegyptiaca (BA), Azadirachta indica (AI), and Jatropha curcas (JC), converted into BAEEs, AIEEs and JCEEs respectively via homogeneous catalysis. Quality specifications of the produced biofuels were used to explain pollutant emissions and engine performance observed via a power generator. Under the same conditions, blends of petrodiesel with crude BA or JC oil (50 wt.%) were also investigated. The selected overall methodology âfeedstock-conversion-engineâ led to the proposal of a sustainable alternative fuel. The candidate NEVO is BA oil to which the proposed alkali route should lead to a low cost biodiesel production process thanks to easy operating conditions, associated with a two-stage procedure (glycerol recycling) and a dry-purification method (rice husk ashes). Glycerol addition should be carried out at ambient temperature to play positively at phenomena occurring in the reacting medium (chemical kinetics, chemical equilibrium, phase equilibrium). Tests on power generator demonstrated that BAEEs led to cleaner combustion than petrodiesel, particularly for the most harmful emissions (light carbonyls and ultrafine particulate matter)
Strength of forest edge effects on litter-dwelling macro-arthropods across Europe is influenced by forest age and edge properties
International audienceAim: Forests are highly fragmented across Western Europe, making forest edges im âportant features in many agricultural landscapes. Forest edges are subject to strong abiotic gradients altering the forest environment and resulting in strong biotic gradi âents. This has the potential to change the forest's capacity to provide multiple eco âsystem services such as nutrient cycling, carbon sequestration and natural pest control. Soil organisms play a key role in this perspective; however, these taxa are rarely considered in forest edge research.Location: A latitudinal gradient of 2,000 km across Western Europe.Methods: We sampled six dominant taxa of litterâdwelling macroâarthropods (car âabid beetles, spiders, harvestmen, centipedes, millipedes and woodlice) in forest edges and interiors of 192 forest fragments in 12 agricultural landscapes. We related their abundance and community composition to distance from the edge and the inter âaction with forest age, edge orientation and edge contrast (contrast between land use types at either side of the edge).Results: Three out of six macroâarthropod taxa have higher activityâdensity in forest edges compared to forest interiors. The abundance patterns along forest edgeâtoâinâterior gradients interacted with forest age. Forest age and edge orientation also influ âenced withinâfragment compositional variation along the forest edgeâtoâinterior gradient. Edge contrast influenced abundance gradients of generalist predators. In general, older forest fragments, southâoriented edges and edges along structurally more continuous land use (lower contrast between forest and adjacent land use) re âsulted in stronger edgeâtoâinterior gradients while recent forests, northâoriented edges and sharp land use edges induced similarity between forest edge and interior along the forest edgeâtoâinterior gradients in terms of species activityâdensity and composition.Main conclusions: Edge effects on litterâdwelling macroâarthropods are anticipated to feedback on important ecosystem services such as nutrient cycling, carbon se âquestration and natural pest control from small forest fragments
Classification of river morphology and hydrology to support management and restoration
The work leading to this paper has received funding from the European Unionâs FP7 programme under Grant Agreement No. 282656 (REFORM
High ecosystem service delivery potential of small woodlands in agricultural landscapes
Global forest loss and fragmentation have strongly increased the frequency of forest patches smaller than a few hectares. Little is known about the biodiversity and ecosystem service supply potential of such small woodlands in comparison to larger forests. As it is widely recognized that high biodiversity levels increase ecosystem functionality and the delivery of multiple ecosystem services, small, isolated woodlands are expected to have a lower potential for ecosystem service delivery than large forests hosting more species. We collected data on the diversity of six taxonomic groups covering invertebrates, plants and fungi, and on the supply potential of five ecosystem services and one disservice within 224 woodlands distributed across temperate Europe. We related their ability to simultaneously provide multiple ecosystem services (multiservice delivery potential) at different performance levels to biodiversity of all studied taxonomic groups (multidiversity), forest patch size and age, as well as habitat availability and connectivity within the landscape, while accounting for macroclimate, soil properties and forest structure. Unexpectedly, despite their lower multidiversity, smaller woodlands had the potential to deliver multiple services at higher performance levels per area than larger woodlands of similar age, probably due to positive edge effects on the supply potential of several ecosystem services. Biodiversity only affected multiservice delivery potential at a low performance level as well as some individual ecosystem services. The importance of other drivers of ecosystem service supply potential by small woodlands in agricultural landscapes also depended on the level of performance and varied with the individual ecosystem service considered. Synthesis and applications. Large, ancient woodlands host high levels of biodiversity and can therefore deliver a number of ecosystem services. In contrast, smaller woodlands in agricultural landscapes, especially ancient woodlands, have a higher potential to deliver multiple ecosystem services on a per area basis. Despite their important contribution to agricultural landscape multifunctionality, small woodlands are not currently considered by public policies. There is thus an urgent need for targeted policy instruments to ensure their adequate management and future conservation in order to either achieve multiservice delivery at high levels or to maximize the delivery of specific ecosystem services
High ecosystem service delivery potential of small woodlands in agricultural landscapes
Global forest loss and fragmentation have strongly increased the frequency of forest patches smaller than a few hectares. Little is known about the biodiversity and ecosystem service supply potential of such small woodlands in comparison to larger forests. As it is widely recognized that high biodiversity levels increase ecosystem functionality and the delivery of multiple ecosystem services, small, isolated woodlands are expected to have a lower potential for ecosystem service delivery than large forests hosting more species. We collected data on the diversity of six taxonomic groups covering invertebrates, plants and fungi, and on the supply potential of five ecosystem services and one disservice within 224 woodlands distributed across temperate Europe. We related their ability to simultaneously provide multiple ecosystem services (multiservice delivery potential) at different performance levels to biodiversity of all studied taxonomic groups (multidiversity), forest patch size and age, as well as habitat availability and connectivity within the landscape, while accounting for macroclimate, soil properties and forest structure. Unexpectedly, despite their lower multidiversity, smaller woodlands had the potential to deliver multiple services at higher performance levels per area than larger woodlands of similar age, probably due to positive edge effects on the supply potential of several ecosystem services. Biodiversity only affected multiservice delivery potential at a low performance level as well as some individual ecosystem services. The importance of other drivers of ecosystem service supply potential by small woodlands in agricultural landscapes also depended on the level of performance and varied with the individual ecosystem service considered. Synthesis and applications. Large, ancient woodlands host high levels of biodiversity and can therefore deliver a number of ecosystem services. In contrast, smaller woodlands in agricultural landscapes, especially ancient woodlands, have a higher potential to deliver multiple ecosystem services on a per area basis. Despite their important contribution to agricultural landscape multifunctionality, small woodlands are not currently considered by public policies. There is thus an urgent need for targeted policy instruments to ensure their adequate management and future conservation in order to either achieve multiservice delivery at high levels or to maximize the delivery of specific ecosystem services
ONIRICA A Conceptual Design Study of a Large FoV Near-IR Imager for OWL
The document presents the Final Study of the OWL NIR Imaging CAmera (ONIRICA) instrument design, as it was submitted to the European Southern Observatory. See https://www.eso.org/sci/facilities/eelt/owl/Publications.html, at this web page the document is freely available for download.The scope of this document is to report a conceptual study of an imaging camera that should fully exploit the sensitivity and spatial resolution capabilities of OWL in the near-IR. This camera will take advantage of a low-order correction exploited by an MCAO system. The conceptual study also includes the very preliminary design of the MCAO wavefront sensor that drives the tertiary adaptive mirror of the telescope with the purpose of removing essentially the layers close to the ground. Provisions to extend the design of the WFS to full MCAO correction are also presented. An analysis of the relevant science cases is carried out together with a simulation of the possible results that the camera could achieve, above all in terms of sky coverage and limiting magnitudes and when compared to possible 30-60 meters class competitor telescopes
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