Sustainable management of organic matter in a Swiss arable soil - carbon sequestration dynamics under various farming systems

Soils, often overlooked and underestimated, are intricate ecosystems that support a diverse array of organisms, contribute to global biogeochemical cycles, and play a pivotal role in food production. In addition to being the largest reservoir of terrestrial carbon (C) and a vital regulator of the global climate, soils provide a multitude of ecological services that are essential for the functioning of natural environments and fundamental for human well-being. The ability of arable soils to act as long-term C sinks through the process of C sequestration, directly influences the extent to which human-induced increases in atmospheric carbon dioxide (CO2) can be offset and thus the extent to which climate change can be mitigated. However, the intensive and unsustainable use of arable soils has led to significant losses of soil organic matter (SOM), the storage medium of C in soil, which was accompanied by the loss of soil fertility. This prompted efforts to restore and increase SOM contents in soils through sustainable management, including economically incentivized C farming practices. The overall objective of this thesis was to improve our understanding of how various farming systems influence the dynamics of SOM within the soil. Particular emphasis was given to acquiring detailed insights into the mechanisms that govern SOM stability within different soil fractions. This would consequently allow the evaluation of different soil management strategies in terms of their effectiveness to contribute to climate change mitigation. To achieve this objective, the DOK long-term farming system comparison trial in Switzerland served as an experimental platform for the observation of SOM dynamics. The focus was on four farming systems with different fertilizer types and quantities. A purely minerally fertilized system (CONMIN), a mixed-fertilized system receiving mineral and organic fertilizer as stacked farmyard manure (CONFYM) and a purely organically fertilized system receiving composted manure (BIODYN) were compared with an unfertilized control (NOFERT), over a period of 36 years (1982-2017). In the first study, physical fractionation was used to separate functionally distinct SOM fractions from archived soil samples. The findings revealed that no additional soil organic carbon (SOC) was sequestered in the finest separated soil fraction (<6.3 μm) under any of the farming systems over the whole observation period. The focus on this specific fraction is driven by its significance for long-term C sequestration, as the association of SOM with fine minerals (referred to as MAOM, mineral-associated organic matter) ensures the highest level of stability. The increase of bulk SOC in BIODYN (+13%) and CONFYM (+5%) (CONMIN: -8%; NOFERT: -20%), indicates that additional C accumulation was only recorded in the form of highly labile particulate organic matter (POM), more specifically, occluded particulate organic matter (oPOM), which undergoes initial stabilization via incorporation into aggregates. Interestingly, BIODYN showed the highest oPOM-C, although OM inputs via organic fertilizers were 20% lower compared to CONFYM. This indicates that the qualitative differences of the organic manures are vital for C sequestration and thus for increasing soil fertility. However, this labile fraction was prone to rapid losses within a few days. Considering that POM serves as a precursor to the highly stabilized MAOM, POM losses should be urgently avoided, as this impedes the potential for subsequent long-term C sequestration. Overall, these findings highlight the substantial dependence of soil fertility on the consistent application of organic fertilizers. Furthermore, in the context of climate change mitigation, it is very concerning that even under sustainable management practices over several decades, additional long-term C sequestration was insufficient. This finding was particularly surprising, especially considering that the saturation of the MAOM fraction could be ruled out as a contributing factor. In an effort to fully comprehend this observation, the second study was dedicated exclusively to the detailed examination of the MAOM fraction. Consequently, the second study focused around the elucidation of the turnover dynamics within the MAOM fraction. MAOM samples from 1982 and 2017 were subjected to specific surface area (SSA) measurements before and after removal of OM with sodium hypochlorite (NaOCl). SSA results indicated best conditions for MAOM-C stabilization under organic fertilization and different sorption mechanisms in MAOM between farming systems with and without organic fertilization. In addition, 14C radiocarbon analysis of the MAOM fraction and subsequent estimation of its mean residence times (MRT = measure for SOM permanence in the soil) were performed, using a model that takes into account ‘bomb 14C’ and radioactive decay. Based on the findings of the first study, which indicated unchanged MAOM-C contents in BIODYN and CONFYM, we expected that long-term organic fertilization would enhance MAOM stability, resulting in longer MRTs. However, the findings demonstrated that continuous organic fertilization led to substantially higher MAOM-C turnover rates and significantly shorter MRTs (BIODYN: 140 ± 19 yrs, CONFYM: 138 ± 18 yrs) in comparison to non-organic fertilization (CONMIN: 195 ± 27 yrs, NOFERT: 238 ± 40 yrs). This indicated that MAOM is much more active under organic fertilization. This apparent contradiction, where increased MAOM-C turnover appeared to contribute to constant MAOM-C contents, could however be explained with the concept of ‘dynamic stability’. The results of this thesis provide compelling evidence that the targeted efforts towards increased long-term C sequestration under agricultural management are insufficient. This dampens the high expectations for soil as a potent solution to bring about mitigated climate change. However, these findings fully align with the gradual and increasingly pronounced shift within the scientific community towards prioritizing soil management practices that promote soil fertility, rather than solely focusing on soil management for C sequestration as a means to address climate change. This thesis demonstrated that sustainable organic soil management, accompanied by consistent organic fertilizer inputs, emerges as the most favorable approach in this regard. Specifically, in the case of BIODYN, despite solely increasing C contents in the labile SOM fractions, this can have a beneficial impact on climate, as long as this management approach is sustained

Cryptocurrencies as an Alternative Asset Class

Bitcoin was the first digital currency to rely on a decentralized peer-to-peer network instead of a trusted third party. This was achieved through Bitcoin’s revolutionary underlying technology based on cryptographic proof: the blockchain. After Bitcoin’s emergence, many other so called cryptocurrencies entered the market and we have seen enormous price increases that romised large returns for early users. The return characteristics of cryptocurrencies have been studied by various scholars and some have even declared cryptocurrencies to be an asset class instead of a digital currency. Due to the fast changes in the cryptocurrency market and the increased importance of other cryptocurrencies than Bitcoin, we believe that research focusing on the financial performance of cryptocurrencies should be renewed on a regular basis. Therefore, with this work we aim to shed light on the return characteristics of cryptocurrencies in relation to traditional asset classes and on the potential of cryptocurrencies to improve portfolio diversification. In addition, we investigate the cryptocurrency market, describe selected cryptocurrencies in more detail and provide an overview of potential technological risks arising with the use of cryptocurrencies. Our results indicate that cryptocurrencies provide large return potentials with high levels of volatility but compared to traditional asset classes provide a higher level of return per level of risk. We also find that selected cryptocurrencies can improve diversification in a cryptocurrency portfolio, as well as in a portfolio of international equity and private equity investments. Keywords: Alternative Asset Classes, Cryptocurrency, Portfolio Diversification, Risk-Reward Profile und Cryptocurrency Risk

P4CEP: Towards In-Network Complex Event Processing

In-network computing using programmable networking hardware is a strong trend in networking that promises to reduce latency and consumption of server resources through offloading to network elements (programmable switches and smart NICs). In particular, the data plane programming language P4 together with powerful P4 networking hardware has spawned projects offloading services into the network, e.g., consensus services or caching services. In this paper, we present a novel case for in-network computing, namely, Complex Event Processing (CEP). CEP processes streams of basic events, e.g., stemming from networked sensors, into meaningful complex events. Traditionally, CEP processing has been performed on servers or overlay networks. However, we argue in this paper that CEP is a good candidate for in-network computing along the communication path avoiding detouring streams to distant servers to minimize communication latency while also exploiting processing capabilities of novel networking hardware. We show that it is feasible to express CEP operations in P4 and also present a tool to compile CEP operations, formulated in our P4CEP rule specification language, to P4 code. Moreover, we identify challenges and problems that we have encountered to show future research directions for implementing full-fledged in-network CEP systems.Comment: 6 pages. Author's versio

V.A.C.® Abdominal Dressing System: A Temporary Closure for Open Abdomen

Background and Purpose:: The study reports experience with the recently commercially available V.A.C.® Abdominal Dressing System, a system designed for a temporary closure of an open abdomen situation under negative pressure. The method allows a late primary fascial closure after laparotomy in case of damage control, abdominal compartment syndrome or severe intra-abdominal spesis and facilitates delayed reconstruction of a large ventral hernia. Patients and Methods:: 18 patients with an open abdomen after laparotomy were managed between February 2002 and September 2004. Results:: Twelve patients after primary, one patient after secondary fascial closure and one patient with partially primary closure and resorbable mesh for abdominal wall reconstruction were free of wound infection or dehiscence of the abdominal wall. Evisceration or enteric fistulas were not observed. Five patients died in consequence of severe injury, a multiple organ failure or septic complications. Conclusion:: V.A.C.® Abdominal Dressing System is an effective temporary closure technique for open abdomen in critically ill patients which makes a late primary fascial closure up to 2 months after initial laparotomy possible either in trauma patients or in case of severe intraabdominal infection. The technique is simple and easily mastere

Dynamic stability of mineral-associated organic matter: enhanced stability and turnover through organic fertilization in a temperate agricultural topsoil

Soil organic matter (SOM) plays a vital role for soil quality, sustainable food production and climate change mitigation. It is common knowledge that SOM consists of different pools with varying qualities, quantities, and turnover times. However, it is still poorly understood how mineral and organic fertilization affects the formation and stabilization of mineral-associated organic matter (MAOM) and how long it can remain there. Here, we report on the long-term effects of different farming systems on the stability and turnover of the fine silt and clay-sized MAOM fraction (<6.3 μm) of a Haplic Luvisol (0–20 cm) in the DOK long-term trial (Switzerland). We compared three farming systems with contrasting fertilization (CONMIN = pure mineral, CONFYM = mineral + organic, BIODYN = pure organic) with an unfertilized control (NOFERT) between 1982 and 2017. We performed specific surface area (SSA) measurements on fractionated MAOM samples (<6.3 μm) from 1982 to 2017, before and after removal of OM, measured the 14C activity of all samples during the entire period and estimated the mean residence time (MRT) with a model taking into account ‘bomb 14C’ and radioactive decay. We found constant MAOM-C contents under organic fertilization. Results of SSA analysis indicate best conditions for MAOM-C stabilization under organic fertilization and different sorption mechanisms in MAOM between farming systems with and without organic fertilization. The modelled MRTs were significantly higher in NOFERT (238 ± 40 yrs) and CONMIN (195 ± 27 yrs), compared to CONFYM (138 ± 18 yrs) and BIODYN (140 ± 19 yrs), implying a high C turnover (i.e. more active MAOM) at high C contents under organic fertilization. Our findings show that MAOM is not the dead OM but corroborates the concept of ‘dynamic stability’. Continuous OM inputs from organic fertilizers and their rapid and constant turnover are needed to stabilize the “stable” MAOM-C fraction

Das LEADER+ Programm als Motor einer endogenen Regionalentwicklung - Oberallgäu und Vorarlberg im Vergleich

Dieser Beitrag beschäftigt sich mit einer qualitativen Evaluation des LEADER+ Programms zur Entwicklung ländlicher Räume in den Regionen Oberallgäu und Vorarlberg. Anhand der vom LEADER-Konzept geforderten Kriterien werden die Ergebnisse von Expertengesprächen dargelegt, die merklichen Entwicklungsunterschiede zwischen den beiden benachbarten Regionen aufgezeigt, Entwicklungshemmnisse, Erfolgsfaktoren und Handlungsempfehlungen abgeleitet. Deutlich wird u. a., dass die längere Projektlaufzeit in Vorarlberg und der reichere Erfahrungsschatz zu den besser entwickelten Wertschöpfungsketten und der intensiveren regionalen Zusammenarbeit der Akteure beitragen. Insgesamt ist LEADER+ als sinnvolle projektbezogene Ergänzungsmaßnahme zur klassischen Direktförderung der Landwirtschaft anzusehen, da sektoren- und branchenübergreifende Projekte gefördert werden, die Eigeninitiative und regionale Kooperation der Betroffenen erfordern. Damit kann ein Beitrag zur Überwindung des kommunalen „Kirchturmdenkens“ geleistet werden. Regionale Identität und das Problembewusstsein der Bevölkerung werden geschärft und interregionale Kooperationen werden angestoßen.This paper presents a qualitative evaluation of the LEADER+ programme to support the development of rural space in the Upper Allgäu and Vorarlberg regions. Applying the criteria demanded under the LEADER concept, the paper sets out the results of expert interviews, describes the clear differences in development between these two neighbouring regions, and on this basis identifies both impediments to development and success factors, and derives recommendations for action. One point which emerges is that the longer duration of the project in Vorarlberg, combined with the greater wealth of experience, together account for more highly developed value-added chains and to generally more intensive regional co-operation among the actors involved. Overall, LEADER+ can be regarded as a sensible project-based supplement to the classical instrument of direct subsidies to agriculture as it supports both cross-sectoral and crossbusiness projects which call for both personal initiative and regional identification on the part of those involved. It thus contributes to overcoming the parochial attitudes sometimes displayed by local authorities. At the same time it promotes both a sense of regional identity and problem awareness and provides an impetus for interregional cooperation

Spannungsfeld der Raumfunktionen Almwirtschaft und Tourismus - Kulturlandschaft Isarwinkel/Rissbachtal

Periphere ländliche Räume sind, was die Flächennutzung anbelangt, stark von Land- und Forstwirtschaft geprägt. Im Fall der bayerischen Alpen besteht die multifunktionale Kulturlandschaft zu einem hohen Anteil aus Almflächen. Die Kulturlandschaft bietet ein endogenes Potenzial, da sie eine Grundvoraussetzung für die Attraktivität als Freizeitraum darstellt. Die touristische Inwertsetzung dieser Potenziale erfolgt im oberbayerischen Isarwinkel weitgehend indirekt, direkte touristische Nutzungen von Almen sind Ausnahmen - im Gegensatz zum benachbarten Tiroler Rissbachtal, wo auch die Almwirtschaft eine größere Rolle spielt. Dennoch ist der Tourismus eine wichtige Erwerbsquelle für die Landwirte, v.a. durch das Angebot "Urlaub auf dem Bauernhof", und trägt damit zum Erhalt der Kulturlandschaft trotz zunehmender urbaner Einflüsse, die im Rissbachtal vornehmlich im Naherholungsverkehr raumwirksam werden, maßgeblich bei. Neben der hier weniger angesprochenen Veränderung im Siedlungsbild durch Wohn- und Gewerbebauten wird das Bild der Kulturlandschaft in beiden Untersuchungsgebieten vor allem durch die Zunahme von Waldflächen beeinflusst.With regard to land use, peripheral rural areas are shaped largely by agriculture and forestry. In the case of the Bavarian Alps, this multifunctional cultural landscape consists to a large extent of mountain pastures. The cultural landscape provides endogenous potential as it has to be seen as a key prerequisite of what makes an area attractive for recreational use. In the Isarwinkel areas of Upper Bavaria, the approach to capitalising on this potential through tourism is largely indirect; direct tourism-related uses of mountain pastures are the exception - unlike in the neighbouring Rissbachtal area in Tyrol, where greater importance is also attached to the economic use of mountain pastures. And yet, for farmers tourism is an important source of income (e.g. "holidays on the farm") and thus makes a vital contribution to preserving the cultural landscape, in the face of increasing pressures from urban areas; in Rissbachtal these are felt principally in the traffic generated by day-trippers. In addition to the changes to the pattern of settlement (residential and commercial) which are only touched on in this paper, in both of the areas investigated the appearance of the cultural landscape has been especially affected by the increase in the area covered by woodland

Disturbance Severity and Human-Nature Relationships: A New Approach to Analyze People's Well-Being along a Bark Beetle Infestation Gradient

Contact to nature and greenspace is important for emotional well-being and can promote human health. Forest landscapes provide such access to greenspace, especially in protected areas. However, forested protected areas are impacted by natural disturbances such as bark beetle infestations. On the one hand, such disturbances have positive impacts on ecological processes and biodiversity. On the other hand, they have allegedly negative impacts on the recreational value of a landscape. Limited knowledge about the public's perception of forests subject to natural disturbances still hampers forest management to balance ecological functions and visitors' recreational experience. Thus, our aim was to determine how attitudes towards nature influence the personal well-being in a naturally disturbed landscape. We investigated self-reported well-being and attitudes towards nature in a standardized questionnaire-based survey of 1008 German inhabitants in an experimentally adapted landscape visualization. Self-reported well-being was generally highest in landscapes with relatively few bark-beetle-killed trees. This was especially the case for people who felt included with nature and preferred an appreciative use or preservation of nature. Conversely, people who had previously visited a national park with visible bark beetle infestations rated their personal well-being highest in landscapes with larger proportions of beetle-killed trees. Our results indicate that it is necessary to analyze people's knowledge about and relations to forest landscapes as well as concepts of nature conservation, natural landscapes, and biodiversity to gain a better understanding of people's perceptions of natural disturbances

Can a leader be seen as too ethical? The curvilinear effects of ethical leadership

Ethical leadership predicts important organizational outcomes such as decreased deviant and increased organizational citizenship behavior (OCB). We argued that due to the distinct nature of these two types of employee behaviors, ethical leadership decreases deviance in a linear manner (i.e., more ethical leadership leading to less deviance), but we expected ethical leadership to reveal a curvilinear relationship with respect to OCB. Specifically, we expected that, at lower levels, ethical leadership promotes OCB. However, at high levels, ethical leadership should lead to a decrease in these behaviors. We also examined a mechanism that explains this curvilinear pattern, that is, followers’ perceptions of moral reproach. Our predictions were supported in three organizational field studies and an experiment. These findings offer a better understanding of the processes that underlie the workings of ethical leadership. They also imply a dilemma for organizations in which they face the choice between limiting deviant employee behavior and promoting OCB

The Dawn of Disk Formation in a Milky Way-sized Galaxy Halo: Thin Stellar Disks at z > 4

We present results from GigaEris, a cosmological, N-body hydrodynamical "zoom-in" simulation of the formation of a Milky Way-sized galaxy halo with unprecedented resolution, encompassing of order a billion particles within the refined region. The simulation employs a modern implementation of smoothed-particle hydrodynamics, including metal-line cooling and metal and thermal diffusion. We focus on the early assembly of the galaxy, down to redshift z = 4.4. The simulated galaxy has properties consistent with extrapolations of the main sequence of star-forming galaxies to higher redshifts and levels off to a star formation rate of ∼60 M⊙ yr−1 at z = 4.4. A compact, thin rotating stellar disk with properties analogous to those of low-redshift systems arises already at z ∼ 8. The galaxy rapidly develops a multi-component structure, and the disk, at least at these early stages, does not grow "upside-down" as often reported in the literature. Rather, at any given time, newly born stars contribute to sustain a thin disk. The kinematics reflect the early, ubiquitous presence of a thin disk, as a stellar disk component with vϕ/σR larger than unity is already present at z ∼ 9–10. Our results suggest that high-resolution spectro-photometric observations of very high-redshift galaxies should find thin rotating disks, consistent with the recent discovery of cold rotating gas disks by ALMA. Finally, we present synthetic images for the James Webb Space Telescope NIRCam camera, showing how the early disk would be easily detectable already at those early times