Schattentolerante Grasgemenge für Agroforstsysteme in der Legehennen-Haltung

This field-study focuses on provision of ground vegetation in a silvopoultry system.Silvopoultry is an agroforestry system in which trees are integrated in the chicken run in order to support natural behavior of laying hens. The trial was conducted on an organic farm in Southern England by the Organic Research Centre and aimed to assess the performance of different sward mixtures under trees. The sward mixtures tested included (1) a commercially available “standard” sward, (2) a sward with especially shade tolerant grasses and (3) a diverse sward including legumes and forage herbs. It was found that all mixtures established well under trees and didn’t show significant differences in productivity after six weeks. The “standard” sward mixture showed slightly higher biomass production. Sowing any of the sward mixtures appeared to reduce weed abundance compared to the control

Renewing the Exploration Approach for Mid-Enthalpy Systems: Examples from Northern England and Scotland

After a promising start in the 1970s and 80s, the UK rather fell behind other countries in the search for viable mid-enthalpy geothermal resources. This situation began to turn around in 2004, when the first of three deep geothermal exploration boreholes were drilled in northern England. What distinguished these from earlier drilling in Cornwall was the deliberate search for naturallyhigh permeability associated with major faults, especially those that have undergone strike-slip reactivation during the Cenozoic. Boreholes at Eastgate in the North Pennines targeted buried radiothermal granite, whereas the 1,821m-deep Science Central Borehole in Newcastle upon Tyne targeted a postulated deep sedimentary aquifer (the Fell Sandstones), which were inferred to be connected laterally to the granitic heat source by a major fault (the reactivation of the Iapetus geo-suture). The drilling was in both cases rewarded with impressive heat flows, and in the case of Eastgate with what is believed to be the highest permeability yet found in a deep granite batholith anywhere in the world. In parallel with these developments, a re-assessment was made of the preexisting geothermal heat flow database for the UK, applying newly-standardised correction protocols for palaeoclimatic and topographic distortions, which were found to be particularly marked in Scotland (where only shallow boreholes had been used to establish geothermal gradients in the original 1980s analysis), Similar prospects in northern England (similar to that drilled at Science Central) are now the focus of commercial exploration efforts. Appraisal of fault dispositions relative to the present-day maximum compressive stress azimuth are being used to identify the most promising areas for intersecting fault-related permeability at depth. New geophysical tools – most notably atomic dielectric resonance scanning – are also being appraised for their ability to directly detect features (such as hot brines) which are indicative of localised convection in target fault zones and aquifers

Rapid water-rock interactions evidenced by hydrochemical evolution of flowback fluid during hydraulic stimulation of a deep geothermal borehole in granodiorite : Pohang, Korea

Flowback water from the 4215 m deep (True Vertical Depth) PX-1 borehole, following the August 2017 hydraulic stimulation of a granodiorite geothermal reservoir in Pohang, South Korea, was monitored for a suite of physicochemical, chemical and isotopic parameters. The results provide unique insights into mixing processes, fluid evolution and rapid water-rock interaction in a deep geothermal system. Injected water for stimulation was relatively fresh, oxidising surface water, with temperature 29.5 °C and pH c. 6.5. The flowback water showed an increasing content of most solutes, with the evolution conforming to an exponential ‘flushing’ model for conservative solutes such as chloride. Flowback water became progressively Na–Cl dominated, with a circumneutral pH (7.1) and negative oxidation-reduction potential (c. −180 mV). Some solutes (including, Na, K and Si) increased more rapidly than a flushing model would suggest, implying that these had been acquired by the flowback water due to mineral hydrolysis. Stable isotopes of O and H indicate that initially meteoric waters have undergone geothermal oxygen isotope exchange with minerals. Evolution of redox species in recovered water suggests progressively oxidising zonation around the injection borehole in an otherwise reducing reservoir. Rapidly increasing silica concentrations in flowback water suggests extensive quartz dissolution and indicated a reservoir temperature of up to 169 °C. This lends plausible, if equivocal support to the hypothesis that quartz dissolution by injection water may have contributed to triggering movement on the pre-stressed fault associated with the November 2017 Mw 5.5 Pohang earthquake

Assignment of the Human and Mouse Prion Protein Genes to Homologous Chromosomes

Purified preparations of scrapie prions contain one major macromolecule, designated prion protein (PrP). Genes encoding PrP are found in normal animals and humans but not within the infectious particles. The PrP gene was assigned to human chromosome 20 and the corresponding mouse chromosome 2 using somatic cell hybrids. In situ hybridization studies mapped the human PrP gene to band 20p12→pter. Our results should lead to studies of genetic loci syntenic with the PrP gene, which may play a role in the pathogenesis of prion diseases or other degenerative neurologic disorders

Can we resolve the basin-scale sea-level trend budget from GRACE ocean mass?

Understanding sea level changes at a regional scale is important for improving local sea level projections and coastal management planning. Sea level budget (SLB) estimates derived from the sum of observation of each component close for the global mean. The sum of steric and Gravity Recovery and Climate Experiment (GRACE) ocean mass contributions to sea level calculated from measurements does not match the spatial patterns of sea surface height trends from satellite altimetry at 1° grid resolution over the period 2005–2015. We investigate potential drivers of this mismatch aggregating to subbasin regions and find that the steric plus GRACE ocean mass observations do not represent the small-scale features seen in the satellite altimetry. In addition, there are discrepancies with large variance apparent at the global and hemispheric scale. Thus, the SLB closure on the global scale to some extent represents a cancelation of errors. The SLB is also sensitive to the glacial isostatic adjustment correction for GRACE and to altimery orbital altitude. Discrepancies in the SLB are largest for the Indian-South Pacific Ocean region. Taking the spread of plausible sea level trends, the SLB closes at the ocean-basin scale ( ) but with large spread of magnitude, one third or more of the trend signal. Using the most up-to-date observation products, our ocean-region SLB does not close everywhere, and consideration of systematic uncertainties diminishes what information can be gained from the SLB about sea level processes, quantifying contributions, and validating Earth observation systems

The scope of the Kalman filter for spatio-temporal applications in environmental science

The Kalman filter is a workhorse of dynamical modeling. But there are challenges when using the Kalman filter in environmental science: the complexity of environmental processes, the complicated and irregular nature of many environmental datasets, and the scale of environmental datasets, which may comprise many thousands of observations per time-step. We show how these challenges can be met within the Kalman filter, identifying some situations which are relatively easy to handle, such as datasets which are high-resolution in time, and some which are hard, like areal observations on small contiguous polygons. Overall, we conclude that many applications in environmental science are within the scope of the Kalman filter, or its generalizations

Sulphur isotopes in deep groundwater reservoirs: evidence from post-stimulation flowback at the Pohang geothermal facility, Korea

A hydraulic stimulation was carried out on a granodiorite reservoir in an enhanced geothermal system in August 2017 in Pohang, Korea. Water injected into the 4.2 km deep PX-1 well contained c. 330−360 mg/L sulphate, with a negative δ34S. The resulting flowback water became more saline with time, with sulphate and chloride concentrations and dissolved sulphate δ34S all increasing. Compared with conservative advective-dispersive and mixing models, the flowback contained surplus sulphate with an elevated δ34S. The PX-1 reservoir fluid is saturated with respect to anhydrite at downhole temperatures and pressures. Dissolution by injected surface water of secondary anhydrite along fracture surfaces, most likely with elevated δ34S reflecting the reservoir fluid, is likely to have resulted in an excess of 34S-enriched sulphate in the flowback fluid. An alternative hypothesis involving oxidation of pyrite is also plausible but is stoichiometrically inadequate to account for the observed sulphate excess, and unlikely from a sulphur isotopic perspective. This analysis thus contributes to the evidence for water-rock reactions during stimulation of the Pohang granodiorite

Understanding communication pathways to foster community engagement for health improvement in North West Pakistan

Background: This paper describes the community engagement process undertaken to ascertain the focus, development and implementation of an intervention to improve iodised salt consumption in rural communities in North West Pakistan. The Jirga is a traditional informal structure, which gathers men respected within their community and acts in a governing and decision making capacity in the Pukhtoon culture. The Jirga system had a dual purpose for the study; to access men from the community to discuss the importance of iodised salt, and as an engagement process for the intervention. Methods: A number of qualitative data collection activities were undertaken, with Jirga members and their wives, male and female outreach workers and two groups of women, under and over forty years old. The aim of these were to highlight the communication channels and levers of influence on health behaviour, which were multiple and complex and all needed to be taken into consideration in order to ensure successful and locally sensitive community engagement. Results: Communication channels are described within local families and the communities around them. The key influential role of the Jirga is highlighted as linked both to the standing of its members and the community cohesion ethos that it embodies. Engaging Jirga members in discussions about iodised salt was key in designing an intervention that would activate the most influential levers to decision making in the community. Gendered decision making-processes within the household have been highlighted as restricting women’s autonomy. Whilst in one respect our data confirm this, a more complex hierarchy of decisional power has been highlighted, whereby the concept of ‘wisdom’, an amalgamation of age, experience and education, presents important possibilities. Community members with the least autonomy are the youngest uneducated females, who rely on a web of socially and culturally determined ways to influence decision-making. Conclusions: The major lines of communication and influence in the local community described are placed within the wider literature on community engagement in health improvement. The process of maximisation of local cultural knowledge as part of a community engagement effort is one that has application well beyond the particular setting of this study