Die 逃走 aus der 母語 – Flucht aus der Muttersprache: Auf den Spuren der Mehrsprachigkeit im Streben nach Freiheit bei Tawada Yōko

This article deals with multilingualism and the concept of exophony in literary works by Tawada Yōko. By close reading of her German essay “Von der Muttersprache zur Sprachmutter“, published in Talisman (1996), and the Japanese essay “Dakāru”, published in Ekusofonī: Bogo no soto e deru tabi (2003), this article aims to identify Tawada’s understanding of language and analyzes the language she uses in her literature. The analysis shows that Tawada’s critical approach towards language, culture and identity created reflexive and multilingual texts which raise awareness for the complexity of ‘language’ and the relationship between language and the outside world

Partitioning of ecosystem respiration in a beech forest ecosystem

Wir charakterisierten die Bodenatmung (CO2) und ihre isotopische Zusammensetzung (13C) eines temperaten Buchenwaldes (Fagus sylvatica) im Tages- bzw. Jahresverlauf und untersuchten die Aufteilung der Bodenatmung in ihre autotrophen und heterotrophen Anteile. Die Aufteilung in autotrophe und heterotrophe Bodenatmung wurde durch Vergleichen von Atmungsraten in beringelten und unbehandelten Kontrollflächen erreicht. Zusätzlich untersuchten wir ein umfangreiches Set an potentiellen Substraten und Quellen der Bodenatmung auf ihre δ13C Werte. In Kontrollflächen war Pflanzenmaterial (Laubstreu, Fein- und Grobwurzeln), sowie organisches Material im Boden (SOM) stärker an 13C abgereichert, als Kohlenhydrate in Pflanzenorganen (Zucker im Phloemsaft, Stärke und Zucker in Wurzeln) und Wurzelatmung, was anzeigt, dass ein größerer Teil von Bodenatmung von kürzlich assimiliertem Kohlenstoff angetrieben wird. Wir nahmen an, dass die Isotopensignatur von gelöstem organischem Kohlenstoff (DOC) die Isotopensignatur der Quellen, wie Wurzelexudate oder Produkte von Abbauprozessen, die zum DOC beitragen widerspiegelt. In Kontrollen war DOC stärker angereichert an 13C als in den geringelten Flächen, und wies ähnliche Isotopensignaturen, wie die der Wurzelzucker auf. Das könnte darauf hindeuten, dass Wurzelexudate einen wesentlichen Anteil am DOC ausmachen. Beringeln führte zu einem durchschnittlichen Rückgang der Gesamtbodenatmung um 36 % und zu stärker abgereicherten 13C Signaturen von veratmeten CO2 um 1.5 ‰ im Jahresverlauf, was einen Rückgang der autotrophen Atmung und eine Verschiebung Richtung Abbau von Wurzelstreu und SOM anzeigt. Dies wurde auch von stärker abgereicherten Isotopensignaturen im DOC von geringelten Flächen bestätigt. Wir beobachteten Schwankungen von Bodenatmung und δ13C der Bodenatmung im Tages- und Jahresverlauf. Wir identifizierten Lufttemperatur als Hauptkontrollfaktor für Bodenatmung sowohl in beringelten, als auch in den Kontrollflächen auf verschieden Zeitskalen. In beringelten Flächen korrelierte im Jahresverlauf die Bodenatmung auch mit Bodentemperatur. Die δ13C Werte der Zucker aus dem Phloemsaft wiesen keine signifikanten Veränderungen im Tagesgang auf und korrelierte nicht mit den δ13C Werten der Bodenatmung in Kontrollflächen.We characterised fluxes of soil respired CO2 and corresponding δ13C values in a temperate beech (Fagus sylvatica) forest on a daily and seasonal time scale to investigate autotrophic and heterotrophic contributions to total soil respiration. Partitioning of soil respiration was achieved by comparing rates of soil respiration in girdled plots with non-girdled controls. Additionally we investigated a comprehensive set of potential substrates and sources of soil respiration for their δ13C values. In controls bulk plant litter (leaf, fine and coarse root litter) as well as soil organic matter (SOM) were more depleted in 13C than plant carbohydrates (phloem sap sugars, root starch and sugars) and root respiration, indicating that a major part of soil respiration was fuelled by recently fixed carbon. We assumed that the isotopic signature of dissolved organic carbon (DOC) reflects sources contributing to DOC such as root exudates and products of decomposition. In controls, DOC was enriched in 13C compared to girdled plots, and in the same range as root sugars, indicating that root exudates may contribute substantially to DOC. Girdling led to an average decline of total soil respiration of 36 % and to more depleted 13C signatures of soil respired CO2 by 1.5 ‰ on an annual scale, indicating reduced autotrophic respiration and a shift towards decomposition of root litter and SOM, which was corroborated by more depleted isotopic signatures of DOC in girdled plots. We observed daily and seasonal fluctuations of soil respiration and δ13C of respired CO2. We identified air temperature as a major predictor for soil respiration in both control and girdled plots at the various time scales. In girdled plots soil respiration was further correlated with soil temperature at an annual scale. The δ13C value of phloem sap sugars, however, did not exhibit significant changes on a daily time scale and did not correlate with the δ13C value of soil respiration in control plots

Semantische Analyse unstrukturierter Daten. Review und Analyse: Big-Data Ansatz bei internen Untersuchungen anhand eines Beispiels

In der juristischen Fallbearbeitung steht man immer häufiger vor der Herausforderung, unüberschaubare Massen an Unterlagen berücksichtigen zu müssen. Relevante Information ist verborgen in hunderttausenden E-Mails, Office Dokumenten und PDF-Dateien.All diese Unterlagen zu lesen, zu verstehen und zu beurteilen, ist in der Praxis nicht mehr möglich. Der vorliegende Artikel zeigt ein Vorgehensmodell, wie mit semantischer Inhaltsanalyse die notwendige Informationsgewinnung  in umfangreichen, elektronisch gespeicherten Textbeständen durchgeführt werden kann.    Legal cases are connected more and more with piles of documents. Relevant information is hidden within thousands of E-Mails, Office Documents and PDF Files.  In practice human being can’t read, understand and rate this amount of text any more.The article shows the approach of semantic content analytics and how an investigation team will be enabled again to gain insights from big data electronical  stored text information

Microbial carbon and nitrogen cycling responses to drought and temperature in differently managed mountain grasslands

Grassland management can modify soil microbial carbon (C)and nitrogen (N)cycling, affecting the resistance to extreme weather events, which are predicted to increase in frequency and magnitude in the near future. However, effects of grassland management on microbial C and N cycling and their responses to extreme weather events, such as droughts and heatwaves, have rarely been tested in a combined approach. We therefore investigated whether grassland management affects microbial C and N cycling responses to drought and temperature manipulation. We collected soils from in situ drought experiments conducted in an extensively managed and an abandoned mountain grassland and incubated them at two temperature levels. We measured microbial respiration and substrate incorporation, as well as gross rates of organic and inorganic N cycling to estimate microbial C and N use efficiencies (CUE and NUE). The managed grassland was characterized by lower microbial biomass, lower fungi to bacteria ratio, and higher microbial CUE, but only slightly different microbial NUE. At both sites drought induced a shift in microbial community composition driven by an increase in Gram-positive bacterial abundance. Drought significantly reduced C substrate respiration and incorporation by microbes at both sites, while microbial CUE remained constant. In contrast, drought increased gross rates of N mineralization at both sites, whereas gross amino acid uptake rates only marginally changed. We observed a significant direct, as well as interactive effect between land management and drought on microbial NUE. Increased temperatures significantly stimulated microbial respiration and reduced microbial CUE independent of drought or land management. Although microbial N processing rates showed no clear response, microbial NUE significantly decreased at higher temperatures. In summary in our study, microbial CUE, in particular respiration, is more responsive to temperature changes. Although N processing rates were stronger responding to drought than to temperature microbial NUE was affected by both drought and temperature increase. We conclude that direct effects of drought and heatwaves can induce different responses in soil microbial C and N cycling similarly in the studied land management systems

Microbial carbon limitation : the need for integrating microorganisms into our understanding of ecosystem carbon cycling

Numerous studies have demonstrated that fertilization with nutrients such as nitrogen, phosphorus, and potassium increases plant productivity in both natural and managed ecosystems, demonstrating that primary productivity is nutrient limited in most terrestrial ecosystems. In contrast, it has been demonstrated that heterotrophic microbial communities in soil are primarily limited by organic carbon or energy. While this concept of contrasting limitations, that is, microbial carbon and plant nutrient limitation, is based on strong evidence that we review in this paper, it is often ignored in discussions of ecosystem response to global environment changes. The plant-centric perspective has equated plant nutrient limitations with those of whole ecosystems, thereby ignoring the important role of the heterotrophs responsible for soil decomposition in driving ecosystem carbon storage. To truly integrate carbon and nutrient cycles in ecosystem science, we must account for the fact that while plant productivity may be nutrient limited, the secondary productivity by heterotrophic communities is inherently carbon limited. Ecosystem carbon cycling integrates the independent physiological responses of its individual components, as well as tightly coupled exchanges between autotrophs and heterotrophs. To the extent that the interacting autotrophic and heterotrophic processes are controlled by organisms that are limited by nutrient versus carbon accessibility, respectively, we propose that ecosystems by definition cannot be 'limited' by nutrients or carbon alone. Here, we outline how models aimed at predicting non-steady state ecosystem responses over time can benefit from dissecting ecosystems into the organismal components and their inherent limitations to better represent plant-microbe interactions in coupled carbon and nutrient models

Coupled carbon and nitrogen losses in response to seven years of chronic warming in subarctic soils

Increasing temperatures may alter the stoichiometric demands of soil microbes and impair their capacity to stabilize carbon (C) and retain nitrogen (N), with critical consequences for the soil C and N storage at high latitude soils. Geothermally active areas in Iceland provided wide, continuous and stable gradients of soil temperatures to test this hypothesis. In order to characterize the stoichiometric demands of microbes from these subarctic soils, we incubated soils from ambient temperatures after the factorial addition of C, N and P substrates separately and in combination. In a second experiment, soils that had been exposed to different in situ warming intensities (+0, +0.5, +1.8, +3.4, +8.7, +15.9 °C above ambient) for seven years were incubated after the combined addition of C, N and P to evaluate the capacity of soil microbes to store and immobilize C and N at the different warming scenarios. The seven years of chronic soil warming triggered large and proportional soil C and N losses (4.1 ± 0.5% °C−1 of the stocks in unwarmed soils) from the upper 10 cm of soil, with a predominant depletion of the physically accessible organic substrates that were weakly sorbed in soil minerals up to 8.7 °C warming. Soil microbes met the increasing respiratory demands under conditions of low C accessibility at the expenses of a reduction of the standing biomass in warmer soils. This together with the strict microbial C:N stoichiometric demands also constrained their capacity of N retention, and increased the vulnerability of soil to N losses. Our findings suggest a strong control of microbial physiology and C:N stoichiometric needs on the retention of soil N and on the resilience of soil C stocks from high-latitudes to warming, particularly during periods of vegetation dormancy and low C inputs

Seasonal fluctuations of extracellular enzyme activities are related to the biogeochemical cycling of C, N and P in a tropical terra-firme forest

Extracellular enzymes (EE) play a vital role in soil nutrient cycling and thus affect terrestrial ecosystem functioning. Yet the drivers that regulate microbial activity, and therefore EE activity, remain under debate. In this study we investigate the temporal variation of soil EE in a tropical terra-firme forest. We found that EE activity peaked during the drier season in association with increased leaf litterfall, which was also reflected in negative relationships between EE activities and precipitation. Soil nutrients were weakly related to EE activities, although extractable N was related to EE activities in the top 5 cm of the soil. These results suggest that soil EE activity is synchronized with precipitation-driven substrate inputs and depends on the availability of N. Our results further indicate high investments in P acquisition, with a higher microbial N demand in the month before the onset of the drier season, shifting to higher P demand towards the end of the drier season. These seasonal fluctuations in the potential acquisition of essential resources imply dynamic shifts in microbial activity in coordination with climate seasonality and resource limitation of central-eastern Amazon forests

Fungal and bacterial utilization of organic substrates depends on substrate complexity and N availability

There is growing evidence of a direct relationship between microbial community composition and function, which implies that distinct microbial communities vary in their functional properties. The aim of this study was to determine whether differences in initial substrate utilization between distinct microbial communities are due to the activities of certain microbial groups. We performed a short-term experiment with beech forest soils characterized by three different microbial communities (winter and summer community, and a community from a tree-girdling plot). We incubated these soils with different 13C-labelled substrates with or without inorganic N addition and analyzed microbial substrate utilization by 13C-phospholipid fatty acid (PLFA) analysis. Our results revealed that the fate of labile C (glucose) was similar in the three microbial communities, despite differences in absolute substrate incorporation between the summer and winter community. The active microbial community involved in degradation of complex C substrates (cellulose, plant cell walls), however, differed between girdling and control plots and was strongly affected by inorganic N addition. Enhanced N availability strongly increased fungal degradation of cellulose and plant cell walls. Our results indicate that fungi, at least in the presence of a high N supply, are the main decomposers of polymeric C substrates

Extracellular enzyme activities in tropical soils are driven by seasonal litter input

Background It is relatively unknown if and how seasonal fluctuations of tropical microbial activity affect soil nutrient availability. In tropical forests, nutrient economics are often considered to be centered around phosphorus, which might be a limiting factor to sustain crucial ecosystem processes, such as primary production and decomposition of organic material, thus in turn affecting microbial processes and associated nutrient dynamics of the forest ecosystem. Aims We investigate seasonal fluctuations in extracellular hydrolytic soil enzyme activities and soil nutrients and its relationship with precipitation and litterfall input, in a lowland tropical forest in the Central Amazon region. Methods We analyzed data obtained from monitoring microbial enzyme activity and nutrient dynamics in litter and soil and use stoichiometric enzyme theory and proportional vectors for assessing relative nutrient limitation throughout a year. Results Our results show that precipitation seasonality was driving leaf litterfall, which was subsequently synchronized with extracellular enzyme activities in soil, such that both litterfall and enzyme activities peaked during the dry season. Conclusions Our study indicates that soil extractable nutrient concentrations were positively related to microbial enzyme activities, which thus highlights the importance of soil microbial processes for nutrient cycling in this phosphorus limited ecosystem. Our results suggest that projected shifts in climate seasonality that result in longer and more pronounced dry seasons, might desynchronize seasonal patterns of aboveground nutrient input and belowground microbial activity, and thus leading to a decoupling of nutrient cycling in tropical forest ecosystems