Pedogenic processes are reflected in the effective hydraulic properties in Sphagnum bog profiles

delimited, and horizon-specific soil physical and chemical properties can be specified. This is different for Sphagnum bog peatlands, because Sphagnum mosses grow continually upward in the Acrotelm and leave behind dead plant remnants, which are increasingly decomposed with increasing depth. Thus, a continuous change of soil properties is characteristic for these profiles. To be able to quantify the change of soil hydraulic properties (SHP) with depth in Sphagnum bog profiles, we conducted transient evaporation experiments in the laboratory on a series of samples from the entire profile of the acrotelm. The identified effective pore size densities for Sphagnum are trimodal in the upper part of the acrotelm. We present size classes defining a unifying nomenclature to be used when describing the pore size classes in Sphagnum moss and peat. These size classes refer to the inter-plant pore space which is constituted of the voids between individual mosses, the intra-plant pore space representing the voids between branches and leaves, and the inner-plant pore space which is the space constituted by the water bearing hyaline cells

Baysian and NonBaysian Methods to Estimate the two parameters of Logistic Distribution

In this paper ,the problem of point estimation for the two parameters of logistic distribution has been investigated using simulation technique. The rank sampling set estimator method which is one of the Non_Baysian procedure and Lindley approximation estimator method which is one of the Baysian method were used to estimate the parameters of logistic distribution. Comparing between these two mentioned methods by employing mean square error measure and mean absolute percentage error measure .At last simulation technique used to generate many number of samples sizes to compare between these methods

Comparison of 2D and 3D modeling for deriving effective hydraulic properties of stony soils

Stone, gravel or rock fragments that are embedded in a matrix of fine soil have a substantial effect on effective soil hydraulic and transport properties. Understanding the role of stones in soils is important not only for soil water transport processes such as infiltration, evaporation and redistribution, but also for related solute transport processes. A variety of models has been proposed in the past to predict the systematic effect of varying amounts of stones on effective saturated conductivity and water retention of a soil-stone mixture. Respective studies for unsaturated hydraulic conductivity are still missing. To test the accuracy and validity of such predictive models, and to expand them to unsaturated conductivity, the investigation of virtual porous media, which can be obtained by numerical forward modeling of water and solute transport in soil-stone mixtures is the method of choice. Furthermore, to test the postulate that effective homogeneous properties exist and can replace the heterogeneous system, the ability of a 1D model with assumed homogeneous soil properties to match “observed” state variables and fluxes of a higher-dimensional heterogeneous model under a variety of conditions is a necessary requirement. With few exceptions, such heterogeneous modeling studies have hitherto been performed only for simplified cases, i.e., either under fully saturated conditions, or with a reduced dimensionality, i.e., 2D simulations of soil/stone mixtures. In this work, we use the simulation tool HYDRUS-2D3D to investigate the systematic differences that occur when modeling partially unsaturated transient water in stony soils, based on the Richards equation. Specifically, we compare truly 3D with 2D simulations and discuss the implications for effective 1D hydraulic properties

Digital Platform Ecosystem Governance: Preliminary Findings and Research Agenda

This paper explores collaborative governance in digital platform ecosystems and the governance challenges that may occur in such environments. We analyze three different digital platform ecosystems and identify six unresolved key governance issues that we believe are central to the type of digital platform ecosystems we address. This paper has three contributions. First, we add to the literature on digital platform ecosystems by revealing a set of governance challenges regarding ecosystem forming and sustainability. Second, our findings may serve as recommendations for organizations that are planning to establish or that are already running an ecosystem based on a digital platform. Third, we contribute to digital platform ecosystem research by proposing an agenda for future research in this area

Access to, use of, and experiences with social alarms in home-living people with dementia: results from the [email protected] trial

Background: Social alarms are considered an appropriate technology to ensure the safety and independence of older adults, but limited research has been conducted on their actual use. We, therefore, explored the access, experiences, and use of social alarms among home-bound people with dementia and their informal caregivers (dyads). Methods: From May 2019 to October 2021, the [email protected] mixed-method intervention trial collected data from semi-quantitative questionnaires and qualitative interviews conducted among home-dwelling people with dementia and their informal caregivers in Norway. The study focused on data from the final assessment at 24 months. Results: A total of 278 dyads were included, and 82 participants reached the final assessment. The mean age of the patients was 83 years; 74.6% were female; 50% lived alone; and 58% had their child as a caregiver. A total of 62.2% of subjects had access to a social alarm. Caregivers were more likely to answer that the device was not in use (23.6%) compared to patients (14%). Qualitative data revealed that approximately 50% of the patients were not aware of having such an alarm. Regression analyses assessed that access to a social alarm was associated with increasing age (86–97 years, p = 0.005) and living alone (p < 0.001). Compared to their caregivers, people with dementia were more likely to answer that the device gave them a false sense of security (28% vs. 9.9%), while caregivers were more likely to answer that the social alarm was of no value (31.4% vs.14.0%). The number of social alarms installed increased from 39.5% at baseline to 68% at 24 months. The frequency of unused social alarms increased from 12 months (17.7%) to 24 months (23.5%), and patients were less likely to feel safe during this period (60.8% vs. 70%). Conclusion: Depending on their living situation, patients and family members experienced the installed social alarm differently. There is a gap between access to and the use of social alarms. The results indicate an urgent need for better routines in municipalities with regard to the provision and follow-up of existing social alarms. To meet the users’ changing needs and abilities, passive monitoring may help them adapt to declining cognitive abilities and increase their safety.publishedVersio

Quantifizierung von kapillarem Fluss, Filmfluss und Dampffluss durch inverse Simulation transienter Verdunstungsexperimente

Die Evaporation aus dem unbewachsenen Boden ist eine wichtige Komponente im Wasserhaushalt und der Energiebilanz der Erdoberfläche, insbesondere in ariden und semiariden Gebieten mit geringer Vegetationsdichte. Die Modellierung des Wasserflusses in trockenen Böden und die Vorhersage von realer Evaporation und Grundwasserneubildung stellen eine ständige Herausforderung für die Bodenhydrologie dar und erfordern angemessene Modellkonzepte und Parametrisierungen der bodenhydraulischen Funktionen. Während die Berücksichtigung des Wasserdampftransports in trockenen porösen Medien inzwischen häufig erfolgt, steckt die Parametrisierung der hydraulischen Leitfähigkeitsfunktion im mittleren Wasserspannungsbereich noch immer in den Kinderschuhen und basiert in den meisten Fällen weiterhin auf der Anwendung von Kapillarbündelmodellen und wenigen Datensätzen aus der Literatur mit teilweise eingeschränkter Qualität. Prozesse wie Film- und Eckenfluss wurden zwar an Hand einiger weniger Datensätze untersucht, werden jedoch in der Modellierung von Wasser- und Energieflüssen kaum berücksichtigt. In diesem Beitrag zeigen wir Daten aus transienten Verdunstungsversuchen an großen gepackten Bodensäulen mit erweiterter Instrumentierung in den trockenen Bereich, die mit der Methode der inversen Modellierung prozessbasiert ausgewertet wurden. Es wird untersucht, welche Parametrisierung der hydraulischen Leitfähigkeit zu einer korrekten Beschreibung der Zeitreihen der Wasserspannung führt. Die Analyse wird durch gekoppelte Simulationen des Wasser-, Dampf- und Wärmetransports erweitert. Die Ergebnisse zeigen eindeutig das Scheitern klassischer Parametrisierungen der bodenhydraulischen Funktionen im mittleren und trockenen Bereich. Eine korrekte Beschreibung der Messdaten war nur durch Hinzunahme einer weiteren Komponente in der hydraulischen Leitfähigkeitsfunktion möglich, deren physikalische Ursache wahrscheinlich der Film- und Eckenfluss ist