30 research outputs found

    Renaturierung kleiner Lössbäche – ein Beitrag der Ökologischen Landwirtschaft zum Naturschutz

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    As a part of the interdisciplinary research project ”Integration of nature protection goals with organic farming: an the example from the Hessian ”state domain” [Staatsdomäne] area Frankenhausen”, different restoration measures have been carried out within this site, 15 km north of Kassel. Since 1998, intensive conventional agricultural practices have been substituted with organic farming here. One intention of the agricultural restructuring was to realise nature protection goals in cooperation with sustainable organic agricultural production. The hydrologic portion of the project addresses both the implementation of restoration measures in rivers and streams and their scientific monitoring. Starting in July 2007, several restoration measures were carried out in the hydrologic systems of the Jungfernbach and Esse streams within the Frankenhausen site. Both systems are formed by typical loess streams (catchment size about 9 km2) which had been heavily degraded for several hundred years by intensive agriculture. The most important restoration measures were removal of a piped section of a tributary of the Jungfernbach at Totenhof, restoration of biological passability by removal of weirs and substitution of narrow pipes under farm paths, relocation of a section of the Jungfernbach from the edge of the floodplain to its original location in the centre, widening of narrow sections and partial raising of the deepened stream bed by means of rough ramps (stone bars) and racks made of oak wood or iron. These physical restoration measures were accompanied by a scientific monitoring programme comprising morphological, hydrochemical and biological (aquatic macrophytes, aquatic macroinvertebrates, fish and amphibians) aspects. The aim of this study was to document the original ecological conditions, the restoration measures and the early ecological effects on the stream sections for the first six months following restoration as a basis for further ecological monitoring. The restoration measures effected clear morphological changes in cross-section and passability. The chemical condition of the streams showed slight changes in some aspects following the restoration, e. g. a reduction of phosphorus, magnesium and potassium concentration. Other than macrophytic algae in the newly shaped sections, aquatic macrophytes did not develop over the winter season before the end of the monitoring phase in April 2008. Within the newly shaped stream sections of a small tributary and of the Jungfernbach, up to 14 aquatic macroinvertebrate taxa started to colonise the new habitats 6 months after restoration. Fish fauna were very poorly represented in the streams and included only a few specimens of brown trout (Salmo trutta). This did not change markedly after restoration, possibly due to the isolation of the population caused by impassable weirs downstream of the investigation area.In einem interdisziplinären „Entwicklungs- und Erprobungs-Vorhaben“ der Universität Kassel „Die Integration von Naturschutzzielen in den Ökologischen Landbau am Beispiel der Hessischen Staatsdomäne Frankenhausen“ wurden unterschiedliche Naturschutz-Maßnahmen auf dem Domänengelände durchgeführt. Seit 1998 wird die Staatsdomäne Frankenhausen, die ca. 15 km nördlich von Kassel liegt, ökologisch bewirtschaftet. Ein Aspekt bei der Umstellung auf ökologische Landwirtschaft war die Umsetzung von naturschutz-orientierten Maßnahmen, die in Kooperation mit dem landwirtschaftlichen Betrieb umgesetzt wurden. Ein gewässerökologisches Teilprojekt umfasste unterschiedliche Entwicklungsmaßnahmen an und in Bächen des Jungfernbach- und Esse-Systems auf dem Gelände der Staatsdomäne ab Juli 2007. Beide Bachsysteme (Einzugsgebietsgröße jeweils ca. 9 km2) werden von typischen lössgeprägten Bördenbächen gebildet. Löss-Gebiete zählen zu den durch intensive Landwirtschaft am tiefgreifendsten veränderten Gebieten Deutschlands. Folgende wesentliche Renaturierungsmaßnahmen wurden auf dem Domänengelände umgesetzt: Entfernung der Verrohrung, Offenlegung und Neugestaltung eines Nebenbaches des Jungfernbaches am Totenhof, Rückverlegung eines Jungfernbach-Abschnitts vom Rand der Aue in seine ursprüngliche Lage im Zentrum der Aue nach historischen Angaben, Wiederherstellung der biologischen Durchgängigkeit durch die Entfernung von Wehren und den Ersatz von unpassierbaren Wege-Durchlässen durch voluminösere Durchlässe mit durchgängiger Sohle, partielle Aufweitung enger Querprofile und Anhebung der Gewässersohle durch Stein-Riegel und Sohlrechen aus Stahl oder Eichenholz. Die Maßnahmen wurden von einem wissenschaftlichen Monitoringvorhaben begleitet. Hauptaspekte der wissenschaftlichen Begleitung waren morphologische, hydrochemische und biologische Untersuchungen aquatischer Makrophyten, des Makrozoobenthos, der Fischfauna und der Amphibien. Sie dienten der Erfassung des ökologischen Status quo der Gewässer vor Durchführung der Maßnahmen und der Dokumentation der ökologischen Situation der Gewässer im Anschluss an die Maßnahmen als Basis für die Beobachtung der künftigen Gewässerentwicklung. Die Renaturierungsmaßnahmen induzierten markante Veränderungen der morphologischen Situation der ehemals zu engen und tiefen Querprofile und verbesserten die biologische Durchgängigkeit auf dem Domänengelände. An den Sohlrechen fand während der Folgemonate nach der Renaturierung wegen zu geringer Wasserführung nur ein geringer Totholztransport und damit noch keine erkennbare Sohlanhebung statt. Die chemischen Qualitätsparameter zeigten bei einigen Wasserinhaltsstoffen (z. B. bei Phosphor, Magnesium und Kalium) einen Rückgang der Konzentrationen, der seine Ursachen im Verzicht auf mineralische Düngung mit diesen Stoffen in der ökologischen Landwirtschaft haben könnte. Bei den Wasserpflanzen traten in den neu gestalteten Gewässerabschnitten unmittelbar nach den Renaturierungsmaßnahmen Pionierbestände makrophytischer Algen wie Spirogyra, Cladophora und Vaucheria auf. Über die Herbst- und Wintermonate nach Abschluss der Maßnahmen im Oktober 2009 bis zum Ende der Monitoring-Phase im April 2008 konnten sich noch keine Makrophytenbestände in den neu gestalteten Gewässerabschnitten entwickeln. Im Gegensatz hierzu fand in diesem Zeitraum eine rasche Ansiedlung von 14 Wirbellosen-Taxa im Jungfernbach und 13 Taxa im kleinen, offengelegten und neu gestalteten Bach am Totenhof statt. In diesem Nebengewässer siedelten sich zahlreiche für Lössbache charakteristische Makroinvertebraten bachaufwärts aus dem Jungfernbach heraus an. Die sehr spärliche Fischpopulation, die aus wenigen Bachforellen in einem einzigen Gewässerabschnitt bestand, veränderte sich infolge ihrer räumlichen Isolation durch unterhalb des Untersuchungsraums gelegene Wehre nicht nennenswert

    Lactobacillus Acidophilus/Bifidobacterium Infantis Probiotics Are Beneficial to Extremely Low Gestational Age Infants Fed Human Milk

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    To evaluate the nutrition-related effects of prophylactic Lactobacillus acidophilus/ Bifidobacterium infantis probiotics on the outcomes of preterm infants <29 weeks of gestation that receive human milk and/or formula nutrition. We hypothesize that human-milk-fed infants benefit from probiotics in terms of sepsis prevention and growth. Methods: We performed an observational study of the German Neonatal Network (GNN) over a period of six years, between 1 January, 2013 and 31 December, 2018. Prophylactic probiotic use of L. acidophilus/B. infantis was evaluated in preterm infants <29 weeks of gestation (n = 7516) in subgroups stratified to feeding type: (I) Exclusively human milk (HM) of own mother and/or donors (HM group, n = 1568), (II) HM of own mother and/or donor and formula (Mix group, n = 5221), and (III) exclusive exposure to formula (F group, n = 727). The effect of probiotics on general outcomes and growth was tested in univariate models and adjusted in linear/logistic regression models. Results: 5954 (76.5%) infants received L. acidophilus/B. infantisprophylactically for the prevention of necrotizing enterocolitis (NEC). Probiotic use was associated with improved growth measures in the HM group (e.g., weight gain velocity in g/day: effect size B = 0.224; 95% CI: 2.82–4.35; p < 0.001) but not in the F group (effect size B = −0.06; 95% CI: −3.05–0.28; p = 0.103). The HM group had the lowest incidence of clinical sepsis (34.0%) as compared to the Mix group (35.5%) and the F group (40.0%). Only in the Mix group, probiotic supplementation proved to be protective against clinical sepsis (OR 0.69; 95% CI: 0.59–0.79; p < 0.001). Conclusion: Our observational data indicate that the exposure to L. acidophilus/B. infantis probiotics may promote growth in exclusively HM-fed infants as compared to formula-fed infants. To exert a sepsis-preventive effect, probiotics seem to require human milk

    Melting, bubble-like expansion and explosion of superheated plasmonic nanoparticles

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    We report on time-resolved coherent diffraction imaging of gas-phase silver nanoparticles, strongly heated via their plasmon resonance. The x-ray diffraction images reveal a broad range of phenomena for different excitation strengths, from simple melting over strong cavitation to explosive disintegration. Molecular dynamics simulations fully reproduce this behavior and show that the heating induces rather similar trajectories through the phase diagram in all cases, with the very different outcomes being due only to whether and where the stability limit of the metastable superheated liquid is crossed.Comment: 17 pages, 8 figures (including supplemental material

    Glass in the image – image in glass. preaching in fragments and fragments of preaching . . .

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    Schwier verwys na ’n ‘kritiese metodepluralisme’ wat te midde van die ‘vreemdheid van die teks’ onder meer ‘n blik het op die Bybel as literatuur; wat die rykdom van die Bybelse taal, motiewe, geskiedenisse, beelde, verhale, argumente en literêre strategieë ontgin; wat vra na die verskillende vorms en tekssoorte – wat die narratiewe, profetiese, voorskriftelike, wysheids- en himniese grondvorme van die Bybelse polifonie ondersoek; wat ’n oog het vir retoriek en metaforiese strukture. Naas die veelvuldige vorme van tekskritiek het die sosiaal-historiese, kultuur-antropologiese en kontekstuele of samelewings-betrokke ondersoeke wat gerig is op identiteits- en geloofsbegronding, sowel as verandering van die praxis, ’n wesenlike plek.E.K. (Universiteit van Suid-Afrika) was verantwoordelik vir die deel oor die homiletiek en W.K. (Universiteit van Pretoria) die deel oor die loodglasvensters. Beide dele is geïntegreer en verwerk deur die outeurs.The view that the sermon is an ‘open work of art’, promoted the awareness that the ‘meaning’ of a sermon is not fixed, but that possibilities are presented for the listeners to ‘assign meaning’. ‘Assigning meaning’ does not mean something fully ad libitum: ‘meaning’ is formed within the guidelines of the text from which a sermon stems. Visual works of art could also be based on Biblical texts or stories, analysed and interpreted by the artist. The artist could mould the encounter with the Biblical text into various forms of art, proclaiming the gospel in ways similar to that of a spoken sermon: a work of art could present possibilities for assigning meaning related to faith. In this article the new stained glass windows, symbolically depicting the Liturgical Year, in a Dutch Reformed church in Pretoria, are discussed with a view to the possibilities they present to form part of experience-based religious education in ‘bringing home’ stories from the Bible and aspects of the Liturgical Year. Also asked is how they could function as visual ‘sermons’, speaking and communicating the ‘Word of God’ to the people inside the church, as well as to people on the outside.http://www.hts.org.za/am201

    Indication and technique for arthroscopic stabilization of anterior shoulder instability with multidirectional laxity

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    &lt;jats:title&gt;Abstract&lt;/jats:title&gt;&lt;jats:p&gt;As concomitant hyperlaxity has been identified as an independent risk factor for failure following anterior shoulder stabilization, the treatment of this special pathology remains challenging. There is a broad consensus that a clear differentiation to multidirectional instability and isolated anteroinferior instability should be ensured to avoid unsatisfactory outcomes. Typical features of this patient collective include positive clinical tests for anteroinferior instability and multidirectional shoulder hyperlaxity, findings of an anterior labral lesion and general capsular redundancy in the radiologic assessment, while tests for posterior instability are negative. Surgical treatment should consist of an anteroinferior capsulolabroplasty with concomitant posteroinferior plication to reduce pathological capsular volume. Although there is a lack of clinical evidence, biomechanical investigations suggest that a four-anchor construct with three anterior anchors and one posteroinferior anchor may be sufficient to restore glenohumeral stability. This surgical approach is presented and discussed in the current article.&lt;/jats:p&gt

    Data from: Determinants of between-year burrow re-occupation in a colony of the European Bee-eater Merops apiaster

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    Re-occupation of existing nesting burrows in the European bee-eater Merops apiaster has only rarely – and if so mostly anecdotically – been documented in the literature record, although such behavior would substantially save time and energy. In this study, we quantify burrow re-occupation in a German colony over a period of eleven years and identify ecological variables determining reuse probability. Of 179 recorded broods, 54% took place in a reused burrow and the overall probability that one of 75 individually recognized burrows would be reused in a given subsequent year was estimated as 26.4%. This indicates that between-year burrow reuse is a common behavior in the study colony which contrasts with findings from studies in other colonies. Furthermore, burrow re-occupation probability declined highly significantly with increasing age of the breeding wall. Statistical separation of within- and between-burrow effects of the age of the breeding wall revealed that a decline in re-occupation probability with individual burrow age was responsible for this and not a selective disappearance of burrows with high re-occupation probability over time. Limited duty cycles of individual burrows may be caused by accumulating detritus or decreasing stability with increasing burrow age. Alternatively, burrow fidelity may presuppose pair fidelity which may also explain the observed restricted burrow reuse duty cycles. A consequent next step would be to extend our within-colony approach to other colonies and compare the ecological circumstances under which bee-eaters reuse breeding burrows
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