Wood and fibre properties of fertilized Norway spruce

Very intensive forest management is relatively unexplored in Sweden, and while there is interest in pursuing e.g. the use of fertilizers on selected areas, there is concern about the quality of the wood when growth rate increases. This thesis summarises three studies on wood and fibre properties of Norway spruce grown in two nutrient optimisation experiments and one study from a Norway spruce provenance trial in Sweden. The nutrient optimisation trials were located at 57'08'N, 14'45'E and at 64'07'N, 19'27'E. Increment cores (12 mm diameter) were sampled at breast height from three different treatments and a control. The treatments were irrigation, irrigation combined with liquid fertilization and solid fertilization. Density, microfibril angle, cell wall thickness and radial and tangential cell widths were measured on the wood samples and averages per annual rings and fibre property distributions were analysed. Density, microfibril angle, and cell wall thickness were clearly affected by fertilization. Density and cell wall thickness decreased due to fertilization and microfibril angle increased. Cell widths were moderately affected. Variables describing the inherent development from the pith, such as distance or ring number from pith and ring width, an expression of temporal growth rate and an indicator of varying amounts of earlywood and latewood, were the most important factors explaining differences in fibre properties. The provenance study was situated at 57'56'N, 5'39'E. The differences in density found between provenances were lower than differences caused by fertilization. The possible impact of intense commercial fertilization of Norway spruce for utilization in the pulp and paper industry is discussed

Provenance in Linked Data Integration

The open world of the (Semantic) Web is a global information space offering diverse materials of disparate qualities, and the opportunity to re-use, aggregate, and integrate these materials in novel ways. The advent of Linked Data brings the potential to expose data on the Web, creating new challenges for data consumers who want to integrate these data. One challenge is the ability, for users, to elicit the reliability and/or the accuracy of the data they come across. In this paper, we describe a light-weight provenance extension for the voiD vocabulary that allows data publishers to add provenance metadata to their datasets. These provenance metadata can be queried by consumers and used as contextual information for integration and inter-operation of information resources on the Semantic Web

Congo River sand and the equatorial quartz factory

A never solved problem in sedimentary petrology is the origin of sandstone consisting exclusively of quartz and most durable heavy minerals. The Congo River offers an excellent test case to investigate under which tectonic, geomorphological, climatic, and geochemical conditions pure quartzose sand is generated today. In both upper and lowermost parts of the catchment, tributaries contain significant amounts of feldspars, rock fragments, or moderately stable heavy minerals pointing at the central basin as the main location of the "quartz factory". In Congo sand, quartz is enriched relatively to all other minerals including zircon, as indicated by Si/Zr ratios much higher than in the upper continental crust. Selective elimination of old zircons that accumulated radiation damage through time is suggested by low percentages of grains yielding Archean U-Pb ages despite the basin being surrounded by Archean cratonic blocks. Intense weathering is documented by the lack of carbonate grains in sand and by dominant kaolinite and geochemical signatures in mud. In sand, composed almost entirely of SiO2, the weathering effect is masked by massive addition of quartz grains recycled during multiple events of basin inversion since the Proterozoic. Changes in mineralogical, geochemical, and geochronological signatures across Bas-Congo concur to suggest that approximately 10% of the sand supplied to the Atlantic Ocean is generated by rapid fluvial incision into the recently uplifted Atlantic Rise. The Congo River connects with a huge canyon similar to 30 km upstream of the mouth, and pure quartzose sand is thus funnelled directly toward the deep-sea to feed a huge turbidite fan. Offshore sediments on both sides of the canyon are not derived from the Congo River. They reflect mixed provenance, including illite-rich dust wind-blown from the arid Sahel and augite, hypersthene, and smectite ejected from volcanic centres probably situated along the Cameroon Line in the north. Because mixing of detritus from diverse sources and supply of polycyclic grains almost invariably occurs in the terminal lowland tract of a sediment-routing-system, no ancient sandstone can be safely considered as entirely first-cycle. Moreover, the abundance of pure quartzarenite in the rock record can hardly be explained by chemical weathering or physical recycling alone. The final cleansing of minerals other than quartz, zircon, tourmaline, and rutile requires one or more cycles of chemical dissolution during diagenesis, which operates at higher temperatures and over longer periods than weathering at the Earth's surface

A Research Agenda for Linked Closed Data

While it is preferable that Linked Data is published without access or licence restrictions, there will always remain certain datasets which, perhaps due to financial considerations, cannot be published as Linked Open Data. If these valuable datasets do join the Web of Linked Data, it will be as Linked Closed Data - Linked Data with access and license restrictions. In this paper, we outline a research agenda for Linked Closed Data that considers the effects that access and license restrictions may have on the Web of Linked Data. If implemented poorly, access restrictions have the potential to break URI resolvability, but even when implemented well, we can expect them to affect dataset selection processes and inter-dataset link creation rates. Additionally, there remains the technical challenge of developing and standardising access restriction and automated payment techniques for the Web of Linked Data

Traceability for trustworthy AI: a review of models and tools

Traceability is considered a key requirement for trustworthy artificial intelligence (AI), related to the need to maintain a complete account of the provenance of data, processes, and artifacts involved in the production of an AI model. Traceability in AI shares part of its scope with general purpose recommendations for provenance as W3C PROV, and it is also supported to different extents by specific tools used by practitioners as part of their efforts in making data analytic processes reproducible or repeatable. Here, we review relevant tools, practices, and data models for traceability in their connection to building AI models and systems. We also propose some minimal requirements to consider a model traceable according to the assessment list of the High-Level Expert Group on AI. Our review shows how, although a good number of reproducibility tools are available, a common approach is currently lacking, together with the need for shared semantics. Besides, we have detected that some tools have either not achieved full maturity, or are already falling into obsolescence or in a state of near abandonment by its developers, which might compromise the reproducibility of the research trusted to them

Germination responses to light of four Neotropical forest tree species along an elevational gradient in the southern Central Andes

Seed germination is a key part of plants' life cycle and is mostly affected by the genetic background, the environmental conditions experienced by the mother plant and the seedbed conditions. The germination response to light is essential to optimize germination and seedling establishment in space and time. In addition, the germination response to light is a trait often related to the response of the seeds to their position in the soil (uncovered/buried). Here, we studied the germination response to light of four key tree species of the Yungas forest (Anadenanthera colubrina, Enterolobium contortisiliquum, Jacaranda mimosifolia and Handroanthus impetiginosus) sampled along an elevational and environmental gradient with contrasting vegetation cover and disturbance. Relative light germination (RLG) and mean germination time (MGT) were determined. Final germination was tested under cycles of light (8 h) and darkness (16 h) versus complete darkness (24 h) and elevation, and MGT was tested as a function of elevation of the provenance. The RLG increased from smaller to larger-seeded species. The MGT of three of the studied species was affected by the elevation of the provenance. Complete darkness negatively affected final germination, while two species exhibited a significant interaction between the provenance and light. The variable germination responses to light along the elevational gradient highlights the influence of the environment on germination as a key factor that should be considered for forest management, conservation and restoration projects

Validation of the HEN model for organic laying hens and assessment of nutrition in organic poultry (CTE0202)

Introduction Regulation EC1804/1999 sets out the minimum standards for organic livestock production and UK organic poultry producers have to adhere to for organic poultry. There are several aspects of Regulation EC1804/1999 which are technically and practicably challenging with regards to organic poultry production and most of these relate to feeding organic poultry. The greatest problems relate to the need to feed mainly organic ingredients, there is a future requirement to feed 100% organic ingredients, and the banning of synthetic amino acids in feeds for organic poultry. The issues raised by the introduction of Regulation EC1804/1999 are: 1) how do we match the supply of energy and nutrients to the bird’s needs for health, welfare and performance in a UK organic poultry production system? 2) Do we fully understand the bird’s amino acid needs for metabolic processes and can we meet them when feeding 80% or more organic ingredients? 3) Do UK-grown organic ingredients have lower crude protein and amino acid contents than their non-organic counterparts? If so, this will exacerbate any difficulties in amino acid supply to the birds. 4) What are the implications of Regulation EC1804/1999 in terms of ingredient supply for organic poultry production? These issues were addressed in this project. Firstly by measuring on-farm the hen’s feed metabolisable energy intake responses to temperature in outdoor production systems and examining whether a model (the ADAS HEN model) of inputs (feed metabolisable energy, protein and amino acids) and outputs (egg numbers and weight) could be validated for use in organic egg production systems. If so, this would provide a user-friendly approach for practical decision making at farm level. Secondly, by examining the published literature on recommended nutrient requirements for non-organic poultry and assessing the applicability of the findings to organic poultry. Thirdly, by sampling organically grown crops (wheat, peas and beans) and determining their contents of crude protein and amino acids. Fourthly, by estimating the size of the UK organic poultry flocks and their requirements for organic ingredients. Objectives 1. To validate the HEN model for organic egg production so that the feed energy value relative to protein content may be better matched with feed intake, and energy and nutrient requirements in differing outdoor temperatures. 2. To scope the technical issues relating to the nutrition of organic pullets, laying hens, table birds and breeder flocks. 3. To review the essential amino acid requirements for maintenance, growth, immune system development, behaviour, laying performance, sexual maturity and the risk of prolapse and interpret the relevance of published conventional data to organic poultry production. 4. To examine whether or not there are differences in the contents of crude protein content, lysine, methionine and threonine of organic and non-organic wheat, peas and beans (by analysis). 5. To examine the implications of changes in Regulation EC1804/1999 and Standards (e.g. organic pullet rearing and organic breeder flocks) on the volumes of organic feed ingredients needed for sustained UK organic poultry production (chickens) based on the current sector size. Implication of findings and future work 1. There is an inability to optimise the dietary ratio of metabolisable energy to protein for hens in outdoor production systems, as the hen’s feed metabolisable energy intake responses to low fluctuating outdoor temperatures have not been defined. The implications of this are tempered with respect to organic egg production as the priority when formulating diets is to meet, as far as possible with the limited range of ingredients available, the organic hen’s methionine and lysine requirements, which in practice is resulting in too much crude protein being fed. 2. Feeding excess crude protein will increase the rate of nitrogen excretion from organic poultry, and there will be an increased risk of nitrogen pollution to the air and water environments. 3. Without additional organic methionine-rich protein sources, methionine deficiencies will become more pronounced and more widespread in organic poultry production as the level of permitted non-organic proteinaceous ingredients in the diet fall. This will impact on bird health and welfare. 4. The possibility of lower methionine contents in organically produced wheat, peas and beans will exacerbate problems of methionine supply. 5. There is an urgent need to identify novel sources of organic methionine-rich protein for feeding organic poultry. This is being addressed in Defra-funded project OF0357 ‘Organic egg production – A desk study on sustainable and innovative methods for meeting the hen’s protein requirements’. The project addressed Defra’s policy of supporting the sustainable development of organic poultry production in the UK. The project has provided both Defra and the industry with information about the key scientific and technical problems, and some possible solutions to these problems. Where there are gaps in knowledge it has highlighted future research needs. The move to 100% organic provenance for organic poultry feeds is an important issue for UK consumers