Search results for "Salix"
showing 10 items of 21 documents
Su alcuni aspetti di vegetazione relitta nella Valle dell’Oreto (Palermo) e l’opportunità di una loro tutela finalizzata anche al recupero del paesag…
2006
Feasibility of hyperspectral vegetation indices for the detection of chlorophyll concentration in three high Arctic plants: Salix polaris, Bistorta v…
2018
Remote sensing, which is based on a reflected electromagnetic spectrum, offers a wide range of research methods. It allows for the identification of plant properties, e.g., chlorophyll, but a registered signal not only comes from green parts but also from dry shoots, soil, and other objects located next to the plants. It is, thus, important to identify the most applicable remote-acquired indices for chlorophyll detection in polar regions, which play a primary role in global monitoring systems but consist of areas with high and low accessibility. This study focuses on an analysis of in situ-acquired hyperspectral properties, which was verified by simultaneously measuring the chlorophyll conc…
Dendrochemical assessment of mercury releases from a pond and dredged-sediment landfill impacted by a chlor-alkali plant.
2016
International audience; Although current Hg emissions from industrial activities may be accurately monitored, evidence of past releases to the atmosphere must rely on one or more environmental proxies. We used Hg concentrations in tree cores collected from poplars and willows to investigate the historical changes of Hg emissions from a dredged sediment landfill and compared them to a nearby control location. Our results demonstrated the potential value of using dendrochemistry to record historical Hg emissions from past industrial activities.
Salix breviserrata Flod., novedad para la flora palentina
2016
Hemos encontrado una pequeña población del sauce rastrero Salix breviserrata Flod., novedad para la provincia de Palencia. Esta localización representa el emplazamiento más meridional de la corología global de este taxon alpino, que alcanza el norte de la Península Ibérica. S. breviserrata está catalogado como Vulnerable en la Lista Roja de la flora vascular española, lo que afianza el ya conocido valor florístico del entorno del macizo de Valdecebollas (Palencia, España). We found a small formation of brushes and low scrubs willow dominated by Salix breviserrata Flod., new taxon for the province of Palencia. This location represents the southernmost of the global chorology of this alpine s…
Melampsora allii-fragilis f. sp. galanthi-fragilis reported for first time to cause rust on Galanthus plicatus in Latvia
2010
In Europe, Melampsora allii-fragilis f. sp. galanthi-fragilis (syn. Melampsora galanthi-fragilis) has been reported on leaves of snowdrop (Galanthus nivalis) in Romania (Savulescu, 1953; Bagyanarayana, 2005) and on Galanthus plicatus in Ukraine (Gutsevich, 1952). The GBIF Database has additional records of this fungus on G. nivalis from Austria, Czech Republic and France but the USDA SMML Specimens Database has also records from Hungary and Poland. According to this database, the established distribution area of M. allii-fragilis f. sp. galanthi-fragilis is ‘Central Europe’. Melampsora allii-fragilis f. sp. galanthi-fragilis belongs to the heteroecious rust fungi that require two hosts to c…
Clonal differences in growth and phenolics of willows exposed to elevated ultraviolet-B radiation
2003
Abstract In this study, the effects of elevated ultraviolet-B (UV-B, 280–320 nm) radiation on growth and leaf phenolics were evaluated in clones of dark-leaved willow ( Salix myrsinifolia Salisb.) and tea-leaved willow ( Salix phylicifolia L.). Willows were raised for one growing season in an irradiation field, where they were exposed either to a constant 50% increase in UV-B CIE radiation simulating 20–25% ozone depletion or to a small increase in UV-A radiation (320–400 nm). Control willows were grown in the irradiation field under solar radiation (ambient control). Despite the high constitutive concentrations of a UV-absorbing leaf flavonoid, dihydromyricetin, UV-treatments clearly reduc…
Fast-growing willow (Salix viminalis) as a filler in polyethylene composites
2018
Abstract The study investigated the possibility of using wood flour obtained from fast-growing willow chips (Salix viminalis) as an alternative for standard hard- and softwood flours used in the production of wood polymer composites (WPCs). The composites contained willow flour and polyethylene matrix (OPCs) were prepared, characterized and compared with other WPCs which had been filled with hard- or softwood flours. Moreover, the structural and functional properties were investigated and discussed. Greater hemicellulose contents and lower lignin contents in OPCs resulted in better impact strength values of those materials. Which is interesting, the chemical composition of OPCs was found si…
Sampling procedure in a willow plantation for chemical elements important for biomass combustion quality
2015
Willow (Salix spp.) is expected to contribute significantly to the woody bioenergy system in the future, so more information on how to sample the quality of the willow biomass is needed. The objectives of this study were to investigate the spatial variation of elements within shoots of a willow clone ‘Tordis’, and to reveal the relationship between sampling position, shoot diameters, and distribution of elements. Five Tordis willow shoots were cut into 10–50 cm sections from base to top. The ash content and concentration of twelve elements (Al, Ca, Cd, Cu, Fe, K, Mg, Mn, Na, P, Si, and Zn) in each section were determined. The results showed large spatial variation in the distribution of mos…
Two-Stage Anaerobic Digestion of Energy Crops: Methane Production, Nitrogen Mineralisation and Heavy Metal Mobilisation
2006
Energy crops (willow, sugar beet and grass silage) were digested in pilot scale two-stage anaerobic digesters. The specific methane yields obtained were 0.16, 0.38 and 0.39 m3 kg(-1) added volatile solids (VSadded) for willow, sugar beet and grass, respectively, corresponding to yearly gross energy yields of 15, 53 and 26 megawatt-hours (MWh) per hectare. With grass and sugar beets as substrate, 84-85% of the harvestable methane was obtained within 30 days. In pilot scale two-stage digestion of willow and sugar beet, 56 and 85% of the laboratory scale methane yields were obtained, but digestion of grass in two-stage reactors yielded 5% more methane than digestion in laboratory scale complet…
Sampling procedure in a willow plantation for estimation of moisture content
2015
Abstract Heating value and fuel quality of wood is closely connected to moisture content. In this work the variation of moisture content (MC) of short rotation coppice (SRC) willow shoots is described for five clones during one harvesting season. Subsequently an appropriate sampling procedure minimising labour costs and sampling uncertainty is proposed, where the MC of a single stem section with the length of 10–50 cm corresponds to the mean shoot moisture content (MSMC) with a bias of maximum 11 g kg −1 . This bias can be reduced by selecting the stem section according to the particular clone. The average difference in MSMC between the largest and smallest shoot in a stump was 31 g kg −1 .…