High-resolution in situ stable isotope measurements reveal contrasting atmospheric vapour dynamics above different urban vegetation

Funding Information: This study was funded through the German Research Foundation (DFG) as part of the Research Training Group ‘Urban Water Interfaces’ (UWI; GRK2032/2) and the Einstein Foundation as part of the ‘Modelling surface and groundwater with isotopes in urban catchments’ (MOSAIC) project. Funding for Dörthe Tetzlaff was also received through the Einstein Research Unit ‘Climate and Water under Change’ from the Einstein Foundation Berlin and Berlin University Alliance (grant no. ERU‐2020‐609) and the project BiNatur (BMBF No. 16LW0156). We also acknowledge the BMBF (funding code 033W034A), which supported the stable isotope laboratory and in situ laser analyser. Contributions from Chris Soulsby have also been supported by the Leverhulme Trust through the ISO‐LAND project (grant no. RPG 2018 375). We thank all colleagues involved in the ecohydrological monitoring and daily precipitation and groundwater sampling, but in particular are grateful to Jan Christopher, Jonas Freymüller and Jessica Landgraf. Open Access funding enabled and organized by Projekt DEAL. Publisher Copyright: © 2023 The Authors. Hydrological Processes published by John Wiley & Sons Ltd.Peer reviewedPublisher PD

Upgrade of the ATLAS Muon Trigger for the SLHC

The outer shell of the ATLAS experiment at the LHC consists of a system of toroidal air-core magnets in order to allow for the precise measurement of the transverse momentum p$_T$ of muons, which in many physics channels are a signature of interesting physics processes. For the precise determination of the muon momentum Monitored Drift Tube chambers (MDT) with high position accuracy are used, while for the fast identification of muon tracks chambers with high time resolution are used, able to select muons above a predefined p$_T$ threshold for use in the first Level of the ATLAS triggering system (Level-1 trigger). When the luminosity of the LHC will be upgraded to 4-5 times the present nominal value (SLHC) in about a decade from now, an improvement of the selectivity of the ATLAS Level-1 triggering system will be mandatory in order to cope with the maximum allowed trigger rate of 100 kHz. For the Level-1 trigger of the ATLAS muon spectrometer this means an increase of the p$_T$ threshold for single muons. Due to the limited spatial resolution of the trigger chambers, however, the selectivity for tracks above ~20 GeV/c is insufficient for an effective reduction of the Level-1 rate. We describe how the track coordinates measured in the MDT precision chambers can be used to decisively improve the selectivity for high momentum tracks. The resulting increase in latency will also be discussed.Comment: These are the proceedings of a presentation given at the Topical Workshop of Electronics for Particle Physics 2010 in Aachen, Germany (sept., 20-24, 2010

Taschengeld und Sparverhalten bei Grundschulkindern: eine empirische Untersuchung in Nordwestdeutschland

This working paper presents the results of a survey of 330 schoolchildren from three primary schools in small rural towns in North-Rhine Westfalia and Lower Saxony. The questions dealt with pocket money and savings behaviour and the data related to two main issues. Firstly, a measure was made to the extent to which the investigated families apply the central recommendations of pocket money pedagogy. Secondly, the data was considered in the context of the established attitudinal-behavioural models. The results reveal that approximately 80 % of the children receive pocket money regularly. The average weekly amount is EUR 2.29, with a standard deviation of EUR 1.61. Within the attitude-behaviour-framework, a relationship was proven between the perceived behavioural control of the children and their ability to come out with the pocket money. This results supplements and confirms analogous findings from health didactics, in which strengthening the self esteem of children has emerged a central pillar of prevention of unhealthy behaviour. --

In situ measurements of soil and plant water isotopes: a review of approaches, practical considerations and a vision for the future

The number of ecohydrological studies involving water stable isotope measurements has been increasing steadily due to technological (e.g., field-deployable laser spectroscopy and cheaper instruments) and methodological (i.e., tracer approaches or improvements in root water uptake models) advances in recent years. This enables researchers from a broad scientific background to incorporate water-isotope-based methods into their studies. Several isotope effects are currently not fully understood but might be essential when investigating root water uptake depths of vegetation and separating isotope processes in the soil–vegetation–atmosphere continuum. Different viewpoints exist on (i) extraction methods for soil and plant water and methodological artifacts potentially introduced by them, (ii) the pools of water (mobile vs. immobile) measured with those methods, and (iii) spatial variability and temporal dynamics of the water isotope composition of different compartments in terrestrial ecosystems. In situ methods have been proposed as an innovative and necessary way to address these issues and are required in order to disentangle isotope effects and take them into account when studying root water uptake depths of plants and for studying soil–plant–atmosphere interaction based on water stable isotopes. Herein, we review the current status of in situ measurements of water stable isotopes in soils and plants, point out current issues and highlight the potential for future research. Moreover, we put a strong focus and incorporate practical aspects into this review in order to provide a guideline for researchers with limited previous experience with in situ methods. We also include a section on opportunities for incorporating data obtained with described in situ methods into existing isotope-enabled ecohydrological models and provide examples illustrating potential benefits of doing so. Finally, we propose an integrated methodology for measuring both soil and plant water isotopes in situ when carrying out studies at the soil–vegetation–atmosphere continuum. Several authors have shown that reliable data can be generated in the field using in situ methods for measuring the soil water isotope composition. For transpiration, reliable methods also exist but are not common in ecohydrological field studies due to the required effort. Little attention has been paid to in situ xylem water isotope measurements. Research needs to focus on improving and further developing those methods. There is a need for a consistent and combined (soils and plants) methodology for ecohydrological studies. Such systems should be designed and adapted to the environment to be studied. We further conclude that many studies currently might not rely on in situ methods extensively because of the technical difficulty and existing methodological uncertainties. Future research needs to aim on developing a simplified approach that provides a reasonable trade-off between practicability and precision and accuracy

Contract farming and the adoption of sustainable farm practices: Empirical evidence from cashew farmers in Ghana

Contract farming has been shown to increase agricultural productivity and thus welfare of farmers in developing countries. However, studies that look at the potential environmental effects of contract farming remain quite scanty. This is however crucial, since contract farming may contribute to intensification in cultivation of the contracted crops, in terms of area and the intensity of inputs used. This study investigates the impact of participation in contract farming on sustainable farm practices, using a marginal treatment effects (MTEs) approach to account for potential selection bias and heterogeneity across households. The empirical results show significant heterogeneity in the effects of contract farming on the intensity of sustainable farm practice use. In particular, farmers with high propensity to participate in contract farming tend to have low probabilities of using sustainable farm practices. The findings of this study not only provide new insights into the heterogeneous effects of contract farming, but also entry points for further research to address the dual challenge of agriculture to produce sufficient food, while reducing the adverse impact on the environment

Performance of the ATLAS Muon Drift-Tube Chambers at High Background Rates and in Magnetic Fields

The ATLAS muon spectrometer uses drift-tube chambers for precision tracking. The performance of these chambers in the presence of magnetic field and high radiation fluxes is studied in this article using test-beam data recorded in the Gamma Irradiation Facility at CERN. The measurements are compared to detailed predictions provided by the Garfield drift-chamber simulation programme

High Rate Proton Irradiation of 15mm Muon Drifttubes

Future LHC luminosity upgrades will significantly increase the amount of background hits from photons, neutrons and protons in the detectors of the ATLAS muon spectrometer. At the proposed LHC peak luminosity of 5*10^34 1/cm^2s, background hit rates of more than 10 kHz/cm^2 are expected in the innermost forward region, leading to a loss of performance of the current tracking chambers. Based on the ATLAS Monitored Drift Tube chambers, a new high rate capable drift tube detecor using tubes with a reduced diameter of 15mm was developed. To test the response to highly ionizing particles, a prototype chamber of 46 15mm drift tubes was irradiated with a 20 MeV proton beam at the tandem accelerator at the Maier-Leibnitz Laboratory, Munich. Three tubes in a planar layer were irradiated while all other tubes were used for reconstruction of cosmic muon tracks through irradiated and non-irradiated parts of the chamber. To determine the rate capability of the 15mm drift-tubes we investigated the effect of the proton hit rate on pulse height, efficiency and spatial resolution of the cosmic muon signals

Development of Muon Drift-Tube Detectors for High-Luminosity Upgrades of the Large Hadron Collider

The muon detectors of the experiments at the Large Hadron Collider (LHC) have to cope with unprecedentedly high neutron and gamma ray background rates. In the forward regions of the muon spectrometer of the ATLAS detector, for instance, counting rates of 1.7 kHz/square cm are reached at the LHC design luminosity. For high-luminosity upgrades of the LHC, up to 10 times higher background rates are expected which require replacement of the muon chambers in the critical detector regions. Tests at the CERN Gamma Irradiation Facility showed that drift-tube detectors with 15 mm diameter aluminum tubes operated with Ar:CO2 (93:7) gas at 3 bar and a maximum drift time of about 200 ns provide efficient and high-resolution muon tracking up to the highest expected rates. For 15 mm tube diameter, space charge effects deteriorating the spatial resolution at high rates are strongly suppressed. The sense wires have to be positioned in the chamber with an accuracy of better than 50 ?micons in order to achieve the desired spatial resolution of a chamber of 50 ?microns up to the highest rates. We report about the design, construction and test of prototype detectors which fulfill these requirements

Editorial: The Green Side of the Water Cycle: New Advances in the Study of Plant Water Dynamics

info:eu-repo/semantics/publishedVersio