Shrub establishment favoured and grass dominance reduced in acid heath grassland systems cleared of invasive Rhododendron ponticum

Abstract Rhododendron ponticum L. is a damaging invasive alien species in Britain, favouring the moist, temperate climate, and the acidic soils of upland areas. It outshades other species and is thought to create a soil environment of low pH that may be higher in phytotoxic phenolic compounds. We investigated native vegetation restoration and R. ponticum regeneration post-clearance using heathland sites within Snowdonia National Park, Wales; one site had existing R. ponticum stands and three were restoring post-clearance. Each site also had an adjacent, uninvaded control for comparison. We assessed whether native vegetation restoration was influenced post-invasion by soil chemical properties, including pH and phytotoxic compounds, using Lactuca sativa L. (lettuce) bioassays supported by liquid chromatography-mass spectroscopy (LC-MSn). Cleared sites had higher shrub and bare ground cover, and lower grass and herbaceous species cover relative to adjacent uninvaded control sites; regenerating R. ponticum was also observed on all cleared sites. No phenolic compounds associated with R. ponticum were identified in any soil water leachates, and soil leachates from cleared sites had no inhibitory effect in L. sativa germination assays. We therefore conclude that reportedly phytotoxic compounds do not influence restoration post R. ponticum clearance. Soil pH however was lower beneath R. ponticum and on cleared sites, relative to adjacent uninvaded sites. The lower soil pH post-clearance may have favoured shrub species, which are typically tolerant of acidic soils. The higher shrub cover on cleared sites may have greater ecological value than unaffected grass dominated sites, particularly given the recent decline in such valuable heathland habitats. The presence of regenerating R. ponticum on all cleared sites however highlights the critical importance of monitoring and re-treating sites post initial clearance

Creating and curating an archive: Bury St Edmunds and its Anglo-Saxon past

This contribution explores the mechanisms by which the Benedictine foundation of Bury St Edmunds sought to legitimise and preserve their spurious pre-Conquest privileges and holdings throughout the Middle Ages. The archive is extraordinary in terms of the large number of surviving registers and cartularies which contain copies of Anglo-Saxon charters, many of which are wholly or partly in Old English. The essay charts the changing use to which these ancient documents were put in response to threats to the foundation's continued enjoyment of its liberties. The focus throughout the essay is to demonstrate how pragmatic considerations at every stage affects the development of the archive and the ways in which these linguistically challenging texts were presented, re-presented, and represented during the Abbey’s history

Telemediations

Postprin

Alkaline and Organosolv Lignins from Furfural Residue: Structural Features and Antioxidant Activity

Furfural residue (FR), composed mainly of cellulose and lignin, is an industrial waste produced during furfural manufacture. In this study, dioxane, alkali, ethanol, alkali-ethanol, and alkaline hydrogen peroxide (AHP) were used to extract lignins from FR. The structural features of these lignins obtained were characterized by sugar analysis, GPC, UV, FT-IR, and HSQC spectra. As compared to dioxane lignin (DL), other lignins showed lower molecular weights (Mw) owing to the partial cleavage of the linkages between lignin units. Results from HSQC spectra revealed that β-O-4' and β-5' were still the major linkages of the FR lignin. Moreover, p-coumaric and ferulic acids were released and co-precipitated in the lignin preparations extracted with alkali and AHP, whereas part of the esters in DL were preserved during the dioxane extraction. Antioxidant activity investigation indicated that the antioxidant property of the alkali and alkali-ethanol lignins was higher than that of the commercial antioxidant, butylated hydroxytoluene

Rhododendron data on regeneration of communities in Snowdonia

Data to support publication, including community data, chemicals etc

Genetic control of pulp and timber properties in maritime pine (Pinus pinaster Ait.)

Wood is one of our most important natural resources and has been exploited for many hundreds of years as fuel, building material and a source of paper. Its composition is variable among and within species. The ability to monitor the intra-specific variability is a prerequisite to improve wood and end-products properties. This paper describes a study of the genetic control of a large set of wood properties, including growth, timber quality traits, wood chemical composition, kraft pulp production parameters and pulp properties, in a 12 $\times$ 12 half diallel of maritime pine (Pinus pinaster Ait.). While relatively high (h$^{2}_{\rm ns} > 0.3$) narrow-sense heritabilities were observed for density heterogeneity, lignin content, alpha-cellulose content and coarseness, no significant genetic effect was detected for hemi cellulose, water extractives, kraft pulp production parameters and pylodin. Slightly lower heritabilities ($0.15 < {\rm h}^{2}_{\rm ns} < 0.3$) were also obtained for wood density and fibre properties (length, width, curl, zero span). As a consequence and considering the phenotypic coefficient of variation obtained for these traits, improvement by selection of trees with outstanding wood quality is feasible. Nevertheless, it seems obvious that wood quality breeding can not be done without taking into account growth, and the only way to manage this constraint (negative correlation between growth and density) will be the constitution of elite “wood quality" populations in a already growth improved genetic population.Déterminisme génétique des propriétés du bois impliquées dans la production papetière et la qualité du bois d'œuvre chez le Pin maritime (Pinus pinaster Ait.). Le bois, une des ressources naturelles les plus importantes, est exploité depuis des centaines d'années comme combustible, matériau de construction et source de papier. Sa composition est très variable, non seulement entre espèces mais aussi au niveau intra spécifique. La compréhension de cette variabilité intra spécifique est un pré-requis de l'amélioration des propriétés des produits à base de bois. L'objectif de l'étude présentée ici est la compréhension du déterminisme génétique de plusieurs caractères impliqués dans la composition chimique et les propriétés du bois (caractéristiques physiques, paramètres de production industrielle et propriétés de la pâte) grâce à l'étude d'un demi diallèle 12 $\times$ 12. Bien que des héritabilités au sens strict relativement élevées (h$^{2}_{\rm ns} >0,3$) aient été obtenues pour l'hétérogénéité de la densité, les contenus en lignine et en alpha-cellulose et la masse linéique, aucun effet génétique significatif n'a été mis en évidence pour le contenu en hémi-cellulose, les extractibles, les paramètres de production de pâtes kraft, et la densité estimée grâce au pilodyn. Des héritabilités plus faibles ($0.15 < {\rm h}^{2}_{\rm ns} < 0.3$) ont quant à elles été obtenues pour la densité du bois et les propriétés des fibres (longueur, largeur, courbure, rigidité). En conséquence, considérant les coefficients de variation phénotypiques obtenus pour ces caractères, des gains génétiques significatifs peuvent être attendus. Néanmoins, l'amélioration des propriétés du bois ne pourra pas se faire sans prendre en compte la croissance. Le seul moyen de gérer cette contrainte (induite par des corrélations négatives entre croissance et densité) sera la constitution de populations élites pour la qualité du bois au sein de bases génétiques déjà améliorées pour la croissance

Genetic control of pulp and timber properties in maritime pine (Pinus pinaster Ait.)

Wood is one of our most important natural resources and has been exploited for many hundreds of years as fuel, building material and a source of paper. Its composition is variable among and within species. The ability to monitor the intra-specific variability is a prerequisite to improve wood and end-products properties. This paper describes a study of the genetic control of a large set of wood properties, including growth, timber quality traits, wood chemical composition, kraft pulp production parameters and pulp properties, in a 12 $\times$ 12 half diallel of maritime pine (Pinus pinaster Ait.). While relatively high (h$^{2}_{\rm ns} > 0.3$) narrow-sense heritabilities were observed for density heterogeneity, lignin content, alpha-cellulose content and coarseness, no significant genetic effect was detected for hemi cellulose, water extractives, kraft pulp production parameters and pylodin. Slightly lower heritabilities ($0.15 < {\rm h}^{2}_{\rm ns} < 0.3$) were also obtained for wood density and fibre properties (length, width, curl, zero span). As a consequence and considering the phenotypic coefficient of variation obtained for these traits, improvement by selection of trees with outstanding wood quality is feasible. Nevertheless, it seems obvious that wood quality breeding can not be done without taking into account growth, and the only way to manage this constraint (negative correlation between growth and density) will be the constitution of elite “wood quality" populations in a already growth improved genetic population.Déterminisme génétique des propriétés du bois impliquées dans la production papetière et la qualité du bois d'œuvre chez le Pin maritime (Pinus pinaster Ait.). Le bois, une des ressources naturelles les plus importantes, est exploité depuis des centaines d'années comme combustible, matériau de construction et source de papier. Sa composition est très variable, non seulement entre espèces mais aussi au niveau intra spécifique. La compréhension de cette variabilité intra spécifique est un pré-requis de l'amélioration des propriétés des produits à base de bois. L'objectif de l'étude présentée ici est la compréhension du déterminisme génétique de plusieurs caractères impliqués dans la composition chimique et les propriétés du bois (caractéristiques physiques, paramètres de production industrielle et propriétés de la pâte) grâce à l'étude d'un demi diallèle 12 $\times$ 12. Bien que des héritabilités au sens strict relativement élevées (h$^{2}_{\rm ns} >0,3$) aient été obtenues pour l'hétérogénéité de la densité, les contenus en lignine et en alpha-cellulose et la masse linéique, aucun effet génétique significatif n'a été mis en évidence pour le contenu en hémi-cellulose, les extractibles, les paramètres de production de pâtes kraft, et la densité estimée grâce au pilodyn. Des héritabilités plus faibles ($0.15 < {\rm h}^{2}_{\rm ns} < 0.3$) ont quant à elles été obtenues pour la densité du bois et les propriétés des fibres (longueur, largeur, courbure, rigidité). En conséquence, considérant les coefficients de variation phénotypiques obtenus pour ces caractères, des gains génétiques significatifs peuvent être attendus. Néanmoins, l'amélioration des propriétés du bois ne pourra pas se faire sans prendre en compte la croissance. Le seul moyen de gérer cette contrainte (induite par des corrélations négatives entre croissance et densité) sera la constitution de populations élites pour la qualité du bois au sein de bases génétiques déjà améliorées pour la croissance