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Im November 2015 wurde in Jena das Buch „Die Botaniker Thüringens“ als 18. Beiheft der Schriftenreihe Haussknechtia der Thüringischen Botanischen Gesellschaft e. V. vorgestellt. Es ist die erste Auflistung aller Thüringer Botaniker überhaupt und ergänzt bzw. erweitert das Wissen über bereits zahlreiche in der „Flora von Thüringen“ (Zündorf & al. 2006) erwähnte Botaniker.
Bioindicators are organisms able to provide indirectly or directly information on the impact of pollutants in the environment. The content of heavy metals or other toxic compounds in these living organisms is of great interest to assess the level of contaminants. Leaves of the most common deciduous trees (Acer pseudoplatanus L., Betula pendula Roth, Carpinus betulus L., Cercis siliquastrum L., Ginkgo biloba L., Liquidambar styraciflua, Quercus robur L. and Tilia cordata Miller) and two invasive tree species Ailanthus altissima P. Mill. and Robinia pseudoacacia L., in the City of Bolzano (southern Alps in Northern Italy), were therefore studied to assess their suitability as bioindicators for the trace elements Cd, Cu, Mn, Pb, and Zn, mainly considered as traffic related elements. Leaves and soil samples were investigated, both from high-density traffic roads and control sites of minor traffic impact, such as parks. Our data reveal that Betula pendula has a considerable Zn accumulation potential compared to the other investigated tree species. The maximum value measured for Zn in a Betula specimen is 200 mg kg-1 dry weight. With regard to the soils, considering the geoaccumulation index, most of the analyzed soils belong to the first class, i. e. uncontaminated (Igeo ≤ 0) for all analyzed elements. Moreover, in several samples collected in high traffic areas, Cu and Zn show values within 1 < Igeo ≤ 2 (moderately contaminated). This allows to hypothesize a traffic-related origin for these elements. For this reason, B. pendula can be considered a potential heavy metal accumulator and therefore a good bioindicator for these urban pollutants. Since B. pendula is widely distributed in urban areas in Central and Northern Europe, it can be considered a species suitable for a systematic and comparative monitoring network.
Auf der Grundlage eines neuen Forschungskonzeptes für die Dauerbeobachtung in 26 bayerischen Naturwaldreservaten wurde in vier gemischten, laubbaumdominierten Reservaten mit der Aufnahme von Waldstrukturdaten und waldökologisch besonders wichtigen Artengruppen begonnen. Die dabei gewonnenen Artdaten zur Bodenvegetation, xylobionten Käfern, Schnecken und Pilzen wurden mit den Strukturdaten des Waldbestandes auf Probekreisebene verschnitten. Alle Artengruppen zeigten ähnliche Muster hinsichtlich ihrer Artenzusammensetzung in Beziehung zu Strukturparametern wie dem Buchenanteil des Bestandes und in zweiter Ebene zu Beteiligung der Hainbuche. Zudem konnten Vögel auf der Basis von Rasterkartierungen über die gesamten Reservatsflächen erfasst werden. Es kann daher abgeleitet werden, dass auch Aufnahmen im Rahmen eines entsprechend einfachen Monitorings Beziehungen zwischen den Arten und Waldstrukturen aufzeigen können. Genauere waldökologische Beziehungen zu naturschutzfachlich interessanten Arten wie Naturnähezeigern und Urwaldreliktarten lassen sich mit den Monitoringansätzen jedoch kaum ableiten.
Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a condition of abnormal heart rhythm (arrhythmia), induced by physical activity or stress. Mutations in ryanodine receptor 2 (RyR2), a Ca2+ release channel located in the sarcoplasmic reticulum (SR), or calsequestrin 2 (CASQ2), a SR Ca2+ binding protein, are linked to CPVT. For specific drug development and to study distinct arrhythmias, simple models are required to implement and analyze such mutations. Here, we introduced CPVT inducing mutations into the pharynx of Caenorhabditis elegans, which we previously established as an optogenetically paced heart model. By electrophysiology and video-microscopy, we characterized mutations in csq-1 (CASQ2 homologue) and unc-68 (RyR2 homologue). csq-1 deletion impaired pharynx function and caused missed pumps during 3.7 Hz pacing. Deletion mutants of unc-68, and in particular the point mutant UNC-68(R4743C), analogous to the established human CPVT mutant RyR2(R4497C), were unable to follow 3.7 Hz pacing, with progressive defects during long stimulus trains. The pharynx either locked in pumping at half the pacing frequency or stopped pumping altogether, possibly due to UNC-68 leakiness and/or malfunctional SR Ca2+ homeostasis. Last, we could reverse this ‘worm arrhythmia’ by the benzothiazepine S107, establishing the nematode pharynx for studying specific CPVT mutations and for drug screening.
Background: Malaria remains one of the most serious infections for travellers to tropical countries. Due to the lack of harmonized guidelines a large variety of treatment regimens is used in Europe to treat severe malaria.
Methods: The European Network for Tropical Medicine and Travel Health (TropNet) conducted an 8-year, multicentre, observational study to analyse epidemiology, treatment practices and outcomes of severe malaria in its member sites across Europe. Physicians at participating TropNet centres were asked to report pseudonymized retrospective data from all patients treated at their centre for microscopically confirmed severe Plasmodium falciparum malaria according to the 2006 WHO criteria.
Results: From 2006 to 2014 a total of 185 patients with severe malaria treated in 12 European countries were included. Three patients died, resulting in a 28-day survival rate of 98.4%. The majority of infections were acquired in West Africa (109/185, 59%). The proportion of patients treated with intravenous artesunate increased from 27% in 2006 to 60% in 2013. Altogether, 56 different combinations of intravenous and oral drugs were used across 28 study centres. The risk of acute renal failure (36 vs 17% p = 0.04) or cerebral malaria (54 vs 20%, p = 0.001) was significantly higher in patients ≥60 years than in younger patients. Respiratory distress with the need for mechanical ventilation was significantly associated with the risk of death in the study population (13 vs 0%, p = 0.001). Post-artemisinin delayed haemolysis was reported in 19/70 (27%) patients treated with intravenous artesunate.
Conclusion: The majority of patients with severe malaria in this study were tourists or migrants acquiring the infection in West Africa. Intravenous artesunate is increasingly used for treatment of severe malaria in many European treatment centres and can be given safely to European patients with severe malaria. Patients treated with intravenous artesunate should be followed up to detect and manage late haemolytic events.
This study investigated associations between parenting stress in parents and self-reported stress in children with children's diurnal cortisol secretion and whether these associations are moderated by known stress-regulating capacities, namely child cognitive control. Salivary cortisol concentrations were assessed from awakening to evening on two weekend days from 53 6-to-7-year-old children. Children completed a cognitive control task and a self-report stress questionnaire with an experimenter, while parents completed a parenting stress inventory. Hierarchical, linear mixed effects models revealed that higher parenting stress was associated with overall reduced cortisol secretion in children, and this effect was moderated by cognitive control. Specifically, parenting stress was associated with reduced diurnal cortisol levels in children with lower cognitive control ability and not in children with higher cognitive control ability. There were no effects of self-reported stress in children on their cortisol secretion, presumably because 6-to-7-year-old children cannot yet self-report on stress experiences. Our results suggest that higher cognitive control skills may buffer the effects of parenting stress in parents on their children’s stress regulation in middle childhood. This could indicate that training cognitive control skills in early life could be a target to prevent stress-related disorders.
Progressive neurodegenerative diseases plague millions of individuals both in the United States and across the world. The current pathology of progressive neurodegenerative tauopathies, such as Alzheimer’s disease (AD), Pick’s disease, frontotemporal dementia (FTD), and progressive supranuclear palsy, primarily revolves around phosphorylation and hyperphosphorylation of the tau protein. However, more recent evidence suggests acetylation of tau protein at lysine 280 may be a critical step in molecular pathology of these neurodegenerative diseases prior to the tau hyperphosphorylation. Secondary injury cascades such as oxidative stress, endoplasmic reticulum stress, and neuroinflammation contribute to lasting damage within the brain and can be induced by a number of different risk factors. These injury cascades funnel into a common pathway of early tau acetylation, which may serve as the catalyst for progressive degeneration. The post translational modification of tau can result in production of toxic oligomers, contributing to reduced solubility as well as aggregation and formation of neurofibrillary tangles, the hallmark of AD pathology. Chronic Traumatic Encephalopathy (CTE), caused by repetitive brain trauma is also associated with a hyperphosphorylation of tau. We postulated acetylation of tau at lysine 280 in CTE disease could be present prior to the hyperphosphorylation and tested this hypothesis in CTE pathologic specimens. We also tested for ac-tau 280 in early stage Alzheimer’s disease (Braak stage 1). Histopathological examination using the ac tau 280 antibody was performed in three Alzheimer's cases and three CTE patients. Presence of ac-tau 280 was confirmed in all cases at early sites of disease manifestation. These findings suggest that tau acetylation may precede tau phosphorylation and could be the first "triggering" event leading to neuronal loss. To the best of our knowledge, this is the first study to identify acetylation of the tau protein in CTE. Prevention of tau acetylation could possibly serve as a novel target for stopping neurodegeneration before it fully begins. In this study, we highlight what is known about tau acetylation and neurodegeneration.
Online reading behavior can be regarded as a "new" form of cultural capital in today’s digital world. However, it is unclear whether "traditional" mechanisms of cultural and social reproduction are also found in this domain, and whether they manifest uniformly across countries at different stages of development. This article analyzes whether the early home literacy environment has an impact on informational online reading behavior among adolescents and whether this association varies between countries with different levels of digitalization and educational expansion. Data from the 2009 Programme for International Student Assessment (PISA) were used for the empirical analyses. The results of regression models with country-fixed effects indicate a positive association between literacy activities in early childhood and informational online reading at age 15. This association was quite stable across countries. These findings are discussed in light of cultural and social reproduction theory and digital divide research.
The toolbox for imaging molecules is well-equipped today. Some techniques visualize the geometrical structure, others the electron density or electron orbitals. Molecules are many-body systems for which the correlation between the constituents is decisive and the spatial and the momentum distribution of one electron depends on those of the other electrons and the nuclei. Such correlations have escaped direct observation by imaging techniques so far. Here, we implement an imaging scheme which visualizes correlations between electrons by coincident detection of the reaction fragments after high energy photofragmentation. With this technique, we examine the H2 two-electron wave function in which electron–electron correlation beyond the mean-field level is prominent. We visualize the dependence of the wave function on the internuclear distance. High energy photoelectrons are shown to be a powerful tool for molecular imaging. Our study paves the way for future time resolved correlation imaging at FELs and laser based X-ray sources.
Secretins form multimeric channels across the outer membrane of Gram-negative bacteria that mediate the import or export of substrates and/or extrusion of type IV pili. The secretin complex of Thermus thermophilus is an oligomer of the 757-residue PilQ protein, essential for DNA uptake and pilus extrusion. Here, we present the cryo-EM structure of this bifunctional complex at a resolution of ~7 Å using a new reconstruction protocol. Thirteen protomers form a large periplasmic domain of six stacked rings and a secretin domain in the outer membrane. A homology model of the PilQ protein was fitted into the cryo-EM map. A crown-like structure outside the outer membrane capping the secretin was found not to be part of PilQ. Mutations in the secretin domain disrupted the crown and abolished DNA uptake, suggesting a central role of the crown in natural transformation.
Infections of the central nervous system (CNS) are infrequently diagnosed in immunocompetent patients, but they do occur in a significant proportion of patients with hematological disorders. In particular, patients undergoing allogeneic hematopoietic stem-cell transplantation carry a high risk for CNS infections of up to 15%. Fungi and Toxoplasma gondii are the predominant causative agents. The diagnosis of CNS infections is based on neuroimaging, cerebrospinal fluid examination and biopsy of suspicious lesions in selected patients. However, identification of CNS infections in immunocompromised patients could represent a major challenge since metabolic disturbances, side-effects of antineoplastic or immunosuppressive drugs and CNS involvement of the underlying hematological disorder may mimic symptoms of a CNS infection. The prognosis of CNS infections is generally poor in these patients, albeit the introduction of novel substances (e.g. voriconazole) has improved the outcome in distinct patient subgroups. This guideline has been developed by the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Medical Oncology (DGHO) with the contribution of a panel of 14 experts certified in internal medicine, hematology/oncology, infectious diseases, intensive care, neurology and neuroradiology. Grades of recommendation and levels of evidence were categorized by using novel criteria, as recently published by the European Society of Clinical Microbiology and Infectious Diseases.
Patients who undergo endovascular repair of aortic aneurysms (EVAR) require life-long surveillance because complications including, in particular, endoleaks, aneurysm rupture, and graft dislocation are diagnosed in a certain share of the patient population and may occur at any time after the original procedure. Radiation exposure in patients undergoing EVAR and post-EVAR surveillance has been investigated by previous authors. Arriving at realistic exposure data is essential because radiation doses resulting from CT were shown to be not irrelevant. Efforts directed at identification of factors impacting the level of radiation exposure in both the course of the EVAR procedure and post-EVAR endovascular interventions and CTAs are warranted as potentially modifiable factors may offer opportunities to reduce the radiation. In the light of the risks found to be associated with radiation exposure and considering the findings above, those involved in EVAR and post-EVAR surveillance should aim at optimal dose management.
IKZF1 deletion (ΔIKZF1) is an important predictor of relapse in childhood B-cell precursor acute lymphoblastic leukemia. Because of its clinical importance, we previously mapped breakpoints of intragenic deletions and developed a multiplex PCR assay to detect recurrent intragenic ΔIKZF1. Since the multiplex PCR was not able to detect complete deletions (IKZF1 Δ1-8), which account for ~30% of all ΔIKZF1, we aimed at investigating the genomic scenery of IKZF1 Δ1-8. Six samples of cases with IKZF1 Δ1-8 were analyzed by microarray assay, which identified monosomy 7, isochromosome 7q, and large interstitial deletions presenting breakpoints within COBL gene. Then, we established a multiplex ligation-probe amplification (MLPA) assay and screened copy number alterations within chromosome 7 in 43 diagnostic samples with IKZF1 Δ1-8. Our results revealed that monosomy and large interstitial deletions within chromosome 7 are the main causes of IKZF1 Δ1-8. Detailed analysis using long distance inverse PCR showed that six patients (16%) had large interstitial deletions starting within intronic regions of COBL at diagnosis, which is ~611 Kb downstream of IKZF1, suggesting that COBL is a hotspot for ΔIKZF1. We also investigated a series of 25 intragenic deletions (Δ2–8, Δ3–8 or Δ4–8) and 24 relapsed samples, and found one IKZF1-COBL tail-to-tail fusion, thus supporting that COBL is a novel hotspot for ΔIKZF1. Finally, using RIC score methodology, we show that breakpoint sequences of IKZF1 Δ1-8 are not analog to RAG-recognition sites, suggesting a different mechanism of error promotion than that suggested for intragenic ΔIKZF1.
In der Arbeit wird dargestellt, wie bzw. inwieweit Zuweisungen der Stamm-Nährkraft zu konkreten anhydromorphen Bodenprofilen innerhalb des SEA95-Systems auch auf Basis der Merkmale einzelner Bodenlagen (Horizonte i. w. S.) vorgenommen werden können, um einen Übergang von rein bodenklassenbasierter Zuweisung (über Feinbodenformen) zu einem weitgehend quantifizierenden Verfahren zu ermöglichen. Die benötigten Bodenlagenmerkmale sind Tiefe, Körnung, KMgCaP-Serie (Lithochemie) des Substrates, Humosität, Horizontbezeichnung und teilweise der Basenzustand. Schlüsselgröße der bodenlagenbasierten Nährkraftbestimmung sind körnungs- und lithochemieabhängige Nährkraftgrundwerte. Die Anwendung des Verfahrens wird unter anderem bei fehlender oder schwieriger Nährkraft-Zuweisung zu Feinbodenformen (z. B. Kippböden, auch meliorierte), der Bearbeitung von Konzept-Standortskarten auf Basis flexibler Profilverläufe und als Vergleichsbasis für methodisch abweichende Bewertungen der Nährkraft von Profilen gesehen.
Die Beurteilung von Standortseigenschaften ist eine der wichtigsten forstwirtschaftlichen Voraussetzungen für eine standörtlich angepasste Baumartenwahl. Die traditionelle Standortskartierung Bayerns klassifiziert forstlich relevante Bodeneigenschaften mit einem nominal- und ordinal-skalierten 3-ziffrigen Standortsschlüssel. Im physiographisch
ausgelegten Bayerischen Standortsinformationssystem BaSIS hingegen werden Bodeneinheiten der ÜBK 1 : 25.000 (Übersichtsbodenkarte des Bayerischen Landesamts für Umwelt) mit quantitativen Bodenkenndaten aus zugewiesenen Leitprofilen belegt (nutzbare Feldkapazität, Trockenrohdichte, volumetrischer Skelettgehalt, Tiefenverlauf der Basensättigung u. a.). Ziel dieser Studie ist es, den gutachterlichen Entscheidungsprozess der terrestrischen Wasserhaushaltsstufen (WHH-Stufen) der Standortskartierung unter Verwendung klimatischer und bodenkundlicher Größen statistisch nachzubilden. Datengrundlage sind 1.349 Profile des Bodeninformationssystems des Bayerischen Landesamts für Umwelt, die mit der Standortskarte und Klimakarten verschnitten wurden. Um die Aussagekraft der WHH-Stufe bezüglich der standörtlichen Trockenstress-Gefährdung zu verstehen, wird das Erklärungsmodell der WHH-Stufen mit zwei deterministischen Trockenstress-Größen unterschiedlich komplexer Wasserhaushaltsmodelle verglichen. Der Vergleich zeigt klar, dass die Transpirationsdifferenz TDiff als eine der beiden deterministischen Trockenstress-Größen und gleichzeitig Grundlage zur Ansprache des Wasserhaushalts in BaSIS wesentlich stärker niederschlagsgetrieben ist als die WHH-Stufe der Standortskartierung. In einem letzten Schritt wird – ermutigt durch eine relativ erfolgreiche Nachbildung der WHH-Stufen – das Potential der WHH-Stufen zur Schätzung der nutzbaren Feldkapazität als einer der wichtigsten bodenkundlichen Kennwerte untersucht. Dabei zeigt sich, dass der Einbezug der Standortskartierung in physiographisch basierte Standortsinformationssysteme die Schätzung dieser Parameter verbessern kann. Für die Praxis-Umsetzung empfiehlt sich, stärker nach den Bodeneinheiten oder aggregierten Bodeneinheiten zu differenzieren und Expertenwissen einzubeziehen. Zusammengefasst stellt diese Studie einen Brückenschlag zwischen den genannten Systemen her. Sie bringt einen Erkenntnisgewinn auf beiden Seiten und unterstützt die Kommunikation zwischen Nutzern des einen oder anderen Systems.
Bodeninformationen gehören zu den zentralen Merkmalen, die im Rahmen der forstlichen Standortskartierung erfasst werden. Die Differenzierung orientiert sich dabei weniger an einer streng bodengenetischen Gliederung (Deutsche Bodensystematik), sondern an forstlich relevanten Merkmalen (Standortsbewertungsverfahren). Dabei erweist sich eine Unterscheidung zwischen relativ stabilen Stammeigenschaften und variablen Zustandseigenschaften als sinnvoll. In den forstlichen Kartiersystemen der Bundesländer werden Bodeninformationen in unterschiedlicher Intensität und Qualität aufgenommen. Diese reichen von der bodenkundlich orientierten Bodenformen- oder Substratkartierung mit umfangreicher laboranalytischer Untersetzung bis zu vegetationsökologisch orientierten Aufnahmeverfahren mit indirekter Abschätzung von Bodeneigenschaften. Auch die Abdeckung der kartierten Waldflächen ist unterschiedlich. Perspektiven für die Bereitstellung von Bodeninformationen aus der Standortskartierung ergeben sich durch die Aufarbeitung und Harmonisierung von Altdaten sowie die Integration von weiteren Geodaten und datenintensiven Methoden aus dem Bereich der digitalen Bodenkartierung.
Im Rahmen der Standortskartierung wurde in den ostdeutschen Bundesländern seit den 1950er Jahren über mehrere Jahrzehnte bis heute einheitlich nach einem einstufigen, kombinierten Verfahren kartiert. Dieser Ansatz umfasst die Erkundung von abiotischen und biotischen Standortsfaktoren. Ein Teil der dokumentierten Ergebnisse, die detaillierten Profilbeschreibungen der Weiserprofile für Lokalbodenformen, welche häufig mit bodenphysikalischen und -chemischen Analysen hinterlegt sind, standen bisher nur analog zur Verfügung. Mit der Digitalisierung und expertenbasierten Harmonisierung dieser Altdaten entstehen wertvolle Grundlagen für die rechnergestützte Verarbeitung und Auswertung für aktuelle Fragestellungen. In Thüringen und Sachsen wurden bisher über 2.600 Bodenprofile mit vorliegenden bodenphysikalischen Laboranalysen im Geografischen Informationssystem verortet. Rund 1.000 sächsische Profile wurden vollständig harmonisiert und enthalten horizontweise und lückenlos die bodenphysikalischen Eingangsgrößen für die Anwendung von Pedotransferfunktionen. Mit dieser Datenbasis wurde das Substratfeuchtekonzept angewendet und damit eine räumlich differenzierte Berücksichtigung der Wasserspeicherfähigkeit von Waldböden für waldbauliche Planungen möglich.
Die Zielsetzung dieser Studie war die Evaluierung von publizierten Pedotransferfunktionen (PTF) zur Abschätzung der Trockenrohdichte (TRD) anhand von Ergebnissen der bundesweiten Bodenzustandserhebung im Wald (BZE II). Verschiedene Funktionstypen wurden mit publizierten Parameterwerten am BZE II-Datensatz geprüft. Viele Funktionen zeigten bei einer unkalibrierten Anwendung einen deutlichen Bias (ME) und einen großen Fehler der prognostizierten Werte im Vergleich zu den Messwerten (RMSE). Dem gegenüber erweisen sich die Funktionen von Alexander (1980), Manrique & Jones (1991) und Tamminen & Starr (1994) über alle Bodentiefen als sehr robust. Die Modellgüte der getesteten Funktionen ließ sich durch eine Neukalibrierung am BZE II-Datensatz z. T. wesentlich verbessern, allerdings zeigten viele Funktionen gerade im Bereich hoher TRD systematische Fehler. Die höchste Modellgüte wurde durch ein einfaches gemischtes additives Modell erreicht, das die organische Substanz, die Tiefenstufe, den Skelettgehalt und die Substratgruppe der BZE II als Eingangsdaten berücksichtigt.
We have determined the crystal structures of two decachlorocyclopentasilanes, namely bis(tetra-n-butylammonium) dichloride decachlorocyclopentasilane dichloromethane disolvate, 2C16H36N+·2Cl−·Si5Cl10·2CH2Cl2, (I), and bis(tetraethylammonium) dichloride decachlorocyclopentasilane dichloromethane disolvate, 2C8H20N+·2Cl−·Si5Cl10·2CH2Cl2, (II), both of which crystallize with discrete cations, anions, and solvent molecules. In (I), the complete decachlorocyclopentasilane ring is generated by a crystallographic twofold rotation axis. In (II), one cation is located on a general position and the other two are disordered about centres of inversion. These are the first structures featuring the structural motif of a five-membered cyclopentasilane ring coordinated from both sides by a chloride ion. The extended structures of (I) and (II) feature numerous C—H⋯Cl interactions. In (II), the N atoms are located on centres of inversion and as a result, the ethylene chains are disordered over equally occupied orientations.
Für die Inventurpunkte der zweiten Bundeswaldinventur (BWI2) im Land Brandenburg liegen umfangreiche Bodenund Standortsinformationen vor, die zum einen direkt aus der Bodenzustandserhebung (BZE) stammen und zum anderen mit Hilfe eines ausgewählten Regionalisierungsansatzes generiert wurden. Es erfolgt eine Verknüpfung der Bestandes- und Bodendaten und eine stichprobenbezogene Modellierung der Standorts-Leistungs-Beziehung für die Baumart Kiefer unter Berücksichtigung des Bestandesalters. Die in unterschiedlichen Teilkollektiven ermittelten Regressionsmodelle liefern bei einem R2-Wert von 0,56 identische Einflussgrößen (Nährkraft, Verdunstung) und vergleichbare Parameterkoeffizienten für die Zielgröße der absoluten Höhenbonität. Im Hinblick auf die Bonitäts-Alters-Beziehung ergibt sich aufgrund allgemein verbesserter Standortsbedingungen ein Vorteil der Jungbestände gegenüber den Altbeständen. Dieser Effekt ist umso stärker, je geringer die Stammnährkraft an einem Standort ist.
Im Rahmen eines Waldklimafonds-Projektes werden auf
Basis von Daten der Bodenzustandserfassung im Wald (BZE) und zusätzlichen Bodenprofilen Bodendaten auf die Traktecken der Bundeswaldinventur (BWI) so übertragen, dass nicht nur die Schätzdaten für die Parametrisierung klimasensitiver Wachstumsmodelle verfügbar, sondern auch deren Fehler abgeschätzt werden. Auf der Basis einer unabhängigen Validierung werden klassische Regressionstechniken (OLS, Regression-Kriging) alternativ zu Random-Forestsund BRT-Modellen getestet. Die Beobachtungsdatenbasis für die Modellbildung stammt aus den Messungen und Bodenbeschreibungen der BZE, anderen Projektdaten und der Forstlichen Standortskartierung. Die Regiogalisierung von 13 Zielgrößen (Skelettgehalt, Trockenrohdichte, %Sand, %Schluff, %Ton, Gründigkeit, nFK, Hydromorphie, C-Gehalt, C/N-Verhältnis, Basensättigung, effektive Kationen Austauschkapazität, pHKCl) wird in 1–2 Bodentiefen durchgeführt, was je 25 Regionalisierungsmodelle in 8 aggregierten Bodengroßlandschaften der BÜK1000 ergibt. Für die Modellanwendung werden individuell für die Charakteristika dieser Straten angepasste Prädiktorensets identifiziert und so die Erklärungsgüte der Modelle maximiert. Dieser Beitrag gibt einen Überblick über die bundesweite Auswertungsstruktur, beschränkt sich für methodische Details und Ergebnisse aber hauptsächlich auf die Region Alpenvorland und Nördliche Kalkalpen. Dabei wird gezeigt: 1. dass eine objektive Abgrenzung von Regionalisierungsregionen anhand der naturräumlichen Variabilität der Zielvariablen innerhalb und zwischen Regionen 2. sowie eine länderübergreifende Regionalisierung trotz unterschiedlicher Datenqualitäten in den Ländern mit vertretbarem Fehlerrahmen möglich ist, 3. und die Auswirkung unterschiedlicher Datenqualitäten auf das Regionalisierungsergebnis quantifiziert werden kann. Bisherige Regionalisierungen von Bodendaten haben gezeigt, dass der Anteil der erklärten Parametervarianz zwischen ca. 50 und 80 % zu erwarten ist, dass die Residuen zufällig verteilt und nicht räumlich autokorreliert sind.
Over the last few decades, considerable attention has focused on small-scale studies of invasive plants and invaded systems. Unfortunately, small scale studies rarely provide comprehensive insight into the complexities of biological invasions at macroscales. Systematic and repeated monitoring of biological invasions at broad scales are rare. In this report, we highlight a unique invasive plant database from the national Forest Inventory and Analysis (FIA) program of the United States Forest Service. We demonstrate the importance and capability of this subcontinental-wide database by showcasing several critical macroscale invasion patterns that have emerged from its initial analysis: (1) large portion of the forests systems (39%) in the United States are impacted by invasive plants, (2) forests in the eastern United States harbor more invasive species than the western regions, (3) human land-use legacies at regional to national scalesb may drive large-scale invasion patterns. This accumulated dataset, which continues to grow in temporal richness with repeated measurements, will allow the understanding of invasion patterns and processes at multi-spatial and temporal scales. Such insights are not possible from smaller-scale studies, illustrating the benefit that can be gained by investing in the development of regional to continental-wide invasion monitoring programs elsewhere.
New Zealand harbours a considerable number of alien plants and animals, and is often used as a model region for studies on factors determining the outcome of introductions. Alien birds have been a particular focus of research attention, especially to understand the effect of propagule pressure, as records exist for the numbers of birds introduced to New Zealand. However, studies have relied on compilations of bird numbers, rather than on primary data. Here, we present a case study of the alien yellowhammer (Emberiza citrinella) introduced from the UK to New Zealand, to demonstrate how recourse to the primary literature highlights significant data gaps and misinterpretations in these compilations. We show that the history of the introduction, establishment and spread of the yellowhammer in New Zealand can be reconstructed with surprising precision, including details of the ships importing yellowhammers, their survival rates on board, the numbers and locations of release, and the development of public perception of the species. We demonstrate that not all birds imported were released, as some died or were re-transported to Australia, and that some birds thought to be introductions were in fact translocations of individuals captured in one region of New Zealand for liberation in another. Our study confirms the potential of precise historical reconstructions that, if done for all species, would address criticisms of historical data in the evidence base for the effect of propagule pressure on establishment success for alien populations.
Non-native rats (Rattus spp.) threaten native island species worldwide. Efforts to eradicate them from islands have increased in frequency and become more ambitious in recent years. However, the long-term success of some eradication efforts has been compromised by the ability of rats, particularly Norway rats (Rattus norvegicus) which are good swimmers, to recolonize islands following eradications. In the Falkland Islands, an archipelago in the South Atlantic Ocean, the distance of 250 m between islands (once suggested as the minimum separation distance for an effective barrier to recolonization) has shown to be insufficient. Norway rats are present on about half of the 503 islands in the Falklands. Bird diversity is lower on islands with rats and two vulnerable passerine species, Troglodytes cobbi (the only endemic Falkland Islands passerine) and Cinclodes antarcticus, have greatly reduced abundances and/or are absent on islands with rats. We used logistic regression models to investigate the potential factors that may determine the presence of Norway rats on 158 islands in the Falkland Islands. Our models included island area, distance to the nearest rat-infested island, island location, and the history of island use by humans as driving variables. Models best supported by data included only distance to the nearest potential source of rats and island area, but the relative magnitude of the effect of distance and area on the presence of rats varied depending on whether islands were in the eastern or western sector of the archipelago. The human use of an island was not a significant parameter in any models. A very large fraction (72%) of islands within 500 m of the nearest potential rat source had rats, but 97% of islands farther than 1,000 m away from potential rat sources were free of rats.
Using the MAXENT algorithm, we developed risk maps for eight invasive plant species in southern Transylvania, Romania, a region undergoing drastic land-use changes. Our findings show that invasion risk increased with landscape heterogeneity. Roads and agricultural areas were most prone to invasion, whereas forests were least at risk.
Lantana camara L., considered among the world’s worst invaders is in identity crisis and contentiously referred as Lantana camara L. (sensu lato). Taxonomic ambiguity in L. camara L. (sensu lato), a species complex is one of the grim caveats behind incompetence of its management efforts. Recognizing the extent of variability within the complex, we aim to highlight the need to circumscribe its composition to bring effective management and control efforts into practice. There is a need for clear terminology to examine weedy, naturalized and/or invasive complex constituents that have been placed under the contentious umbrella of 'L. camara L. (sensu lato)'. The time is ripe for invasion ecologists, cytogeneticists and conservationists to collaboratively focus on disentangling the complex and integrate their knowledge and expertise into management and control programs.
Recent critics of invasion biology advocate reduced efforts against nonnative species, arguing that attempts to manage invasions are often costly and futile and that managers are indiscriminately managing species regardless of their impact. Whether this criticism has affected ground-level operations is unknown. A survey of land stewards of a major conservation NGO reveals that this plea has not been heeded; in fact, managers report that they would increase nonnative species management if more resources were available. While respondents overwhelmingly listed nonnative, invasive species as their highest priority for management, we found little evidence supporting the criticism that practitioners focus on nonnative species with minimal ecological impact. Additionally, we found that more conservation practitioners reported managing problematic "weedy" native species over nonnative species that are not invasive. Our results indicate that these managers are selective rather than profligate, targeting species that are having a demonstrable impact or are likely to do so. They feel hamstrung by resource shortages despite their rigorous target selection. Why the increasing literature calling for changed treatment of nonnatives has not led to changed operations is uncertain. Possible reasons are that the critics are not prescriptive or unified about management prioritization, or that these managers simply reject the proposed new paradigm.
The impacts of invasive alien species are greatest when they become dominant members of a community, introduce novel traits, and displace native species. Invasions by alien mollusks represent a novel context by which to compare trait differences between generalist native and introduced herbivores in terrestrial ecosystems. Here, we determined the abundance, habitat, feeding preferences, as well as the metabolic rate of the native Pacific banana slug (Ariolimax columbianus) and the alien black slug (Arion rufus) in the coastal forests of British Columbia, Canada. Through a series of observational and experimental studies, we found that alien slugs are more abundant, differ in their habitat preferences, and consumed more fungi (mushrooms) than native banana slugs. Conversely, in an enclosures experiment we found that herbivory damage by native slugs was higher compared to enclosures with alien only and control enclosures. Finally, metabolic rates were similar for both slug species. These results suggest that alien black slugs possess a suite of traits that make them functionally different from native banana slugs.
Numerous fast growing and highly competitive exotic crops are being selected for production of renewable bioenergy. Tolerance of poor growing conditions with minimal inputs are ideal characteristics for bioenergy feedstocks, but have attracted concern for their potential to become invasive. Miscanthus × giganteus is one of the most promising bioenergy crops in the US, but grower adoption is hindered by high establishment costs due to sterility. Newly developed fertile tetraploid M. × giganteus may streamline cultivation while reducing establishment costs. However, fertile seed dramatically increases the potential propagule pressure, and thus probability of off-site plant establishment. To empirically evaluate the invasive potential of fertile M. × giganteus in the Southeastern US, we compared fitness and spread potential relative to ten grass species comprising 19 accessions under both high and low levels of competition and disturbance. We chose species known to be invasive in the US (positive controls: Arundo donax, naturalized M. sinensis, M. sacchariflorus, Phalaris arundinacea, Sorghum halepense) and non-invasive (negative controls; Andropogon gerardii, ornamental M. sinensis, Panicum virgatum, Sorghum bicolor, Saccharum spp.). This novel design allows us to make relative comparisons of risk among species with varying invasiveness. After three years of establishment and growth in Blacksburg, Virginia, neither aboveground disturbance nor interspecific weed competition influenced fitness for fertile M. × giganteus or our positive and negative control groups. Fertile M. × giganteus produced 346% and 283% greater aboveground biomass than our positive and negative species, respectively. However, fertile M. × giganteus produced 74% fewer inflorescences m-2 than our positive controls and 7% and 51% fewer spikelets inflorescence-1 than the positive and negative control species. After 18 months of growth, we observed the vegetative and seedling spread of three of our positive control species (S. halepense, P. arundinacea, and M. sacchariflorus) outside the cultivated plot into receiving areas of both high and low competition. After 24 months of growth, numerous species were observed outside the cultivated plot including fertile M. × giganteus and 50% of negative control species. Notably, in three years sterile M. × giganteus ‘Illinois’ and Arundo donax never moved from the cultivated plot. The addition of fertile seed appears to increase the potential for offsite movement, but within the geographic confines of our empirical evaluation, fertile M. × giganteus seedlings are more similar to native P. virgatum and were not nearly as fast growing or as competitive as our positive control S. halepense. The use of numerous species providing relative comparisons allow us to draw important conclusions which may help prepare for widespread commercialization, while providing novel methodology for ecological risk assessment of new species.
Identifying factors that underlie invasive species colonisation and change in density could provide valuable insights into the mechanisms of biological invasions and for invasive species management. We examined a suite of factors potentially influencing the landscape-level invasion of Lantana camara L., one of the most ubiquitous invasive species in South Asia. These factors included disturbance factors like forest fires, historical habitat modification, and edge effects, in addition to factors like propagule pressure and habitat suitability. We examined the relative importance of these factors on the colonisation and change in density of L. camara in the Biligiri Rangaswamy Temple Tiger Reserve, Western Ghats, India. We used extensive (1997–2008) datasets tracking the presence and abundance of L. camara and combined these with corresponding data on disturbances, propagule pressure, and habitat suitability. We used an information-theoretic model selection approach to determine the relative importance of each factor on the colonisation and change in density of L. camara. Colonisation was mainly a function of proximity to already established populations (i.e. propagule pressure), whereas increase in L. camara density appeared to be constrained by high fire frequency. Research and management efforts need to recognize the multidimensional nature of mechanisms underlying L. camara’s success during different invasion phases when strategizing interventions to mitigate its effects.
Mutualisms are important structuring forces in ecological communities, influencing ecosystem functions, diversity, and evolutionary trajectories. New interactions, particularly between native and non-native species, are globally increasing in biotic communities as species introductions accelerate. Positive interactions such as novel mutualisms can affect the fitness of organisms in invaded communities. Non-natives can augment native mutualism networks, replace extinct native partners, or disrupt native mutualisms. Because they are actively forming or newly formed, novel mutualisms offer a unique opportunity to examine in real time the factors governing early mutualism formation and stability, including frequency-dependent processes and those relying on specific traits or functions. These central ecological questions have been inferred from long-formed mutualisms, but novel mutualisms may allow a glimpse of successes and failures in ecological time with insights into the relative importance of these factors as ecological systems shift. To this end, this commentary addresses how novel mutualisms inform our understanding of mutualism formation, stability, the importance of functional traits, and niche vs. neutral processes, using examples across multiple systems. Novel mutualism research thus far has been largely limited in both questions and ecosystems, but if more broadly applied could benefit both theoretical and applied ecology.
The trade in plants for planting is a major pathway for the introduction and further spread of alien plants, pests and diseases. Information about the structure of plant trade networks is not generally available, but it is valuable for better assessing the potential risks associated with the trade in live plants and the development of prevention and mitigation measures and policy. The discovery of two larvae of Anoplophora chinensis (citrus longhorn beetle – CLB) in 2009, at a nursery importing Acer palmatum from China in one of the major Dutch tree nursery areas, has resulted in the creation of a detailed dataset on the intra- European Union trade in its potential hosts. This study describes European imports of the primary host of A. chinensis, Acer spp., into the Netherlands (1998-2012) and the effects of the finding in a tree nursery area. In addition, shipments of Acer spp. from 138 producers in the nursery area in 2009 were analysed in a one-off analysis of intra-EU trade. The volume of Acer spp. imports from Asia was stable early during the studied period, and declined to 5% of the initial imports after a period of interceptions, illustrating the effect of regulations. The number of notifications of A. chinensis infestations in imported consignments of Acer spp. increased sharply in the years up to 2007, then declined as imports also reduced. Although plants were shipped to destinations throughout Europe, each producer shipped plants only to few destinations in few countries. Most of the plants were shipped to nurseries in EU countries. These patterns could make it easier to target these high risk destinations for control measures. The lack of transaction records makes it difficult to trace the destination of plants. More systematic electronic record keeping by traders and growers and the data being collated in a database that can be made available to regulatory authorities, together with further studies of plant trade data using network approaches, would be beneficial for improving trace-back and trace-forward and provide better safeguards for plant health and quality.
UV-B radiation represents a potentially selective, yet little studied environmental factor for plant invasions, especially with respect to germination characteristics and seedling establishment in areas of high UV-B exposure such as New Zealand. To explain invasive potential of plant species pre-adaptation and local adaptation to selection factors in the invaded range are two frequently consulted concepts. To test for the relevance of these mechanisms, it is necessary to compare both invasive and non-invasive species, as well as native and exotic origins of invasive species. In the present study, germination success of two congeneric species pairs of the genera Verbascum (Scrophulariaceae) and Echium (Boraginaceae) were investigated under high UV-B intensities. Each genus comprised one species that has successfully invaded New Zealand grasslands and one species that was introduced but has not been invasive in New Zealand. In an among-species approach, pre-adaptation was tested by comparing germination success of native (European) origins of all four species in relation to their different invasive success in New Zealand. In a within-species comparison, native (European) and exotic (New Zealand) origins of the two invasive species were compared to test for local adaptation to UV-B in the invaded range. In both approaches, UV-B radiation inhibited the germination success of all study species. However, the comparison of invasive and non-invasive species of the two genera showed no UV-B-specific pre-adaptation of invasive species to high UV-B intensities. Higher germination success of invasive species probably led to an establishment advantage during colonization of the invaded range. Although local adaptation of exotic populations to UV-B could not be demonstrated in the within-species approach, a genetic shift in germination velocity between native and exotic origins was found. These differences may be ascribed to other relevant environmental factors, e.g. overall irradiation and drought, inducing similar plant responses as under UV-B radiation.
The species of Aequorea attract much scientific interest as they contain the unique Green Fluorescent Protein (GFP). In this work we describe for the first time the discovery of a hydrozoan jellyfish belonging to the genus Aequorea from the Israeli eastern Mediterranean that contains and exhibits fluorescent protein. Finding Aequorea macrodactyla (Brandt, 1835) in the eastern Mediterranean indicates that changes are occurring in the gelatinous fauna of this area. This hydromedusa is known in the seas adjoining the Mediterranean though most of its records are more than four decades old. We examined and identified the newly discovered Israeli Aequorea species by combining two phylogenetic systems, traditional morphological phylogeny and molecular phylogenetics. The molecular identification determined that the species is A. macrodactyla but with minor genetic differences in the mtDNA 16S gene marker. A 1% difference between the Israeli and the Japanese A. macrodactyla was demonstrated, which suggests that the genetic difference between the Israeli and the Japanese population is small but existent. Invasive pathways for this jellyfish were examined by phylogenetic and taxonomic relationships with similar Cnidaria. The results indicate introduction from the Indo-Pacific as invasive pathway, probably by human transportation, and the discovery of A. macrodactyla in the eastern Mediterranean Sea could be interpreted as part of the changes in marine biota as a result of cumulative effects of anthropogenic and global changes that affect the eastern Mediterranean basin.
Status and restoration potential of heathlands and sand grasslands in the southwest of Luxembourg
(2017)
In Europe, semi-natural nutrient-poor ecosystems such as sand grasslands and heathlands have shown extreme declines in surface area and species richness within the last century. The remaining sites are hence of high conservation value. This study analysed the vascular plant species inventory of established and recently restored heathlands and sand grasslands in the southwest of Luxembourg. Analyses to explain differences in vegetation composition between “old” (remnant sites or sites restored a long time ago) and “new” (recently restored) sites in relation to environmental variables were carried out with DCAs and ANOVA/Mann-Whitney-U tests, respectively. The vegetation of old heathlands had few character species of typical heathland communities (Calluno-Ulicetea, Nardetalia), whereas new heathland sites were preponderantly marked by taxa of meso- or eutrophic grasslands and ruderal communities. New heathland sites mainly differed from old sites by higher soil phosphorus contents. Sand grassland vegetation was species-rich and composed by species of the Sedo-Scleranthetea and Festuco-Brometea. With increasing age of the sites, vegetation composition shifted to grass dominance with species of the Molinio-Arrhenateretea. New sand grasslands differed from old sand grasslands by higher soil pH, higher soil potassium content and lower graminoid cover. The differences between new and old sites of both habitat types could mainly be explained by successional processes or were a result of topsoil removal. In some cases, former anthropogenic impact at or in close proximity of restored sites resulted in unsuitable conditions, such as alkaline soil on former landfill sites or highly eutrophic soil due to intensive agriculture. Future management options for the study sites are discussed.
This study describes the vascular flora and community structure of grasslands occurring on heaps of waste rock left by former Zn-Pb mining in relation to the metal content in the soil and other environmental factors. The study was performed on 65 heaps scattered in agricultural land in southern Poland. The sites were described in terms of plant community characteristics, soil physicochemical properties, distance from woodland, altitude and local climate. The number of plant species and proportion of species of the Festuco-Brometea class decreased with increasing heavy metal (Cd, Pb, Zn) content in the soil, and increased with Ca content and pH of the soil. There was a negative relationship between the proportion of the later successional species and heavy metal content in the soil and a positive relationship between plants connected with the earlier stages of succession and metals. Floristic composition was also affected by distance from woodland and height above sea level. The investigated heaps were primarily colonised by native species dispersed by wind, characterised as competitive stresstolerant, ruderal and competitive strategy species. Three types of Carlino acaulis-Brometum erecti (CB) communities were distinguished: CB typicum – dominated by Brachypodium pinnatum, with the highest proportion of calcareous grassland species, CB festucetosum ovinae subass. nova – loose grassland with abundant facultative metallophytes, and the CB rubietosum caesi subass. nova with nutrientdemanding ruderal and woody plants invading from the nearby forest communities. The three subassociations represent different successional stages of Carlino acaulis-Brometum erecti, strongly dependent on both the substrate and spatial relations. The proportions of species traits, especially a high occurrence of endangered species and a very low proportion of alien species show that the post-mining habitats studied have a similar degree of ‘naturalness’ as valuable xerothermic grasslands on nonmetalliferous habitats. They thus may be considered as valuable objects for the protection of plant diversity.
This paper provides a comprehensive survey of the results of phytocoenological research into Alnus incana forests from the alliance Alnion incanae in the Dinarides. Stands from the south-eastern Dinarides (Alnetum incanae = Oxali-Alnetum incanae) were analyzed and compared with those from the north-western Dinarides (Lamio orvalae-Alnetum incanae). The comparison reveals significant differences in the floristic composition and in the degree of differentiation – and particularly in the presence of the species of the Illyrian floristic geoelement. Focus was placed on the area of western Croatia where a geographic variant of Helleborus dumetorum had previously been defined within the association Lamio orvalae-Alnetum incanae. Two of its subtypes, Salix alba and Alnus glutinosa, were determined in our research. The former subtype thrives on occasionally flooded, moist sites, where the floristic composition is dominated by hygrophytes. The latter subtype grows on elevated and drier terraces and is richer in mesophilous species from the surrounding zonal forests. A floristic-sociological comparison of the Lamio orvalae-Alnetum incanae with the related syntaxa indicates the presence of about fourty diagnostic species which accentuate its independence and the need to assess it at the level of an independent, regional association within the alliance Alnion incanae.
The aim of our study was to reveal the differences in the species composition and soil properties of open sandy grasslands dominated by different Festuca species, Festuca vaginata and F. pseudovaginata. Due to the arid conditions, sandy grasslands are generally covered by xerothermic vegetation in which F. vaginata is a typical dominant species. Festuca pseudovaginata, a species newly described by the authors, can also gain dominance in sandy grasslands. However, species composition and soil properties of grasslands dominated by this recently discovered species are still undiscovered. Based on previous coenological studies, we hypothesised that the grasslands characterised by the endemic F. vaginata are more species-rich than those with F.pseudovaginata.
Coenological sampling was carried out in May 2009 at two study sites using the Braun-Blanquet method in quadrats of 2 m × 2 m. Five relevés were sampled in stands dominated by F. vaginata and F. pseudovaginata respectively at two study sites in Central Hungary, resulting in a total of twenty relevés. Analyses were based on the cover scores of vascular plant species and cryptogam crust and values of seven soil properties (pH [KCl], pH [H2O], humus, total N, Ca, P2O5 and K2O) measured in the 0–15 and 15–30 cm soil layers. Soil properties of the grasslands dominated by F. pseudovaginata and F. vaginata (dependent variables) were compared by linear mixed models, where ‘grassland type’ was the fixed factor and ‘site nested in grassland type’ was considered as random factor. Data were analysed by cluster analysis, fusion algorithm was a combinatorial method (minimising increase of variance), and the correlation was used as comparative function. We compared the cover of subordinate species by Mann-Whitney U test. We found that F. pseudovaginata and F. vaginata samples were well separated, and grasslands dominated by F. pseudovaginata had nearly two times more species than those dominated by F. vaginata. Based on the cluster analyses using plant cover and upper 0–15 cm soil layer data, F. pseudovaginata and F. vaginata groups could be well separated. Linear mixed models revealed that F. vaginata grasslands were typical on soils with higher pH, nitrogen, phosphorous and potassium contents compared to F. pseudovaginata grasslands, which indicates a tight connection between the properties of the upper soil layer and the vegetation in sandy grasslands.
Bromus racemosus L. is a rather rare grass species of moist meadows. It has strongly decreased in the course of the 20th century due to intensification of agricultural grassland management, and is therefore included in Red Lists of several European countries. Its winter annual life-cycle is remarkable for a species of permanent grasslands.
The aim of this study is to determine the habitat preference and optimal management of B. racemosus in the Netherlands and surrounding countries. Vegetation, soil and hydrological data from 28 sites in the Netherlands have been compared with B. racemosus cover, and with vegetation data from surrounding countries. The results indicate that B. racemosus is characteristic of Molinio-Arrhenatheretea meadows with good mineralisation and aftermath grazing. The optimum lies in grasslands of the alliance Alopecurion pratensis (Deschampsion cespitosae), but the species ranges from wetter Calthion palustris meadows to drier Arrhenatherion elatioris and Cynosurion cristati grasslands. It prefers intermediate nutrient levels and hydrological conditions (mesic sites), but within this range the highest cover is found in relatively nutrient rich and dry sites. Because of the absence of a seedbank and a low dispersal capability, B. racemosus is vulnerable to changes in grassland management. A management of mowing after 15 June and aftermath grazing is most suitable, since it enables fruit ripening and the maintenance of an open sward, needed for germination and development. The risk of extinction is likely to be higher in flat polders than in floodplain sites with natural relief, where the species may shift between belts in different years.
Vegetation patterns of floodplain forests are highly variable across different habitats in European regions. Their plant communities have been well described from the phytosociological point of view, but plant species richness and composition patterns and their underlying environmental factors are still insufficiently known. Sixty-one vegetation plots of black alder-dominated floodplain forests were sampled in central Slovakia in order to find main environmental predictors affecting floristic diversity of their vegetation. For each vegetation plot with a constant size (400m2), vascular plant species and a set of topographic, climatic, soil physical and chemical characteristics were recorded. A generalized linear model was applied to explain relevance of environmental factors on changes of species richness, whereas the relationship between species composition and explanatory variables was tested using ordination methods. Main gradients of species compositional variation were soil moisture, light, elevation and soil chemistry-related variables. Vascular species richness of plots varied between 19 and 59 (mean 38). Herb-layer species richness was positively related to the soil pH, stream power index and negatively to the concentration of soil iron. These linear trends were accompanied by a hump-shaped response to sand content and a U-shaped response to elevation.
Background: Isolated transient vertigo can be the only symptom of posterior circulation ischemia. Thus, it is important to differentiate isolated vertigo of a cerebrovascular origin from that of more benign origins, as patients with cerebral ischemia have a much higher risk for future stroke than do those with "peripheral" vertigo. The current study aims to identify risk factors for cerebrovascular origin of isolated transient vertigo, and for future cerebrovascular events.
Methods: From the files of 339 outpatients with isolated transient vertigo we extracted history, clinical and technical findings, diagnosis, and follow-up information on subsequent stroke or transient ischemic attack (TIA). Risk factors were analyzed using multivariate regression models (logistic or Cox) and reconfirmed in univariate analyses.
Results: On first presentation, 48 (14.2%) patients received the diagnosis "probable or definite cerebrovascular vertigo". During follow-up, 41 patients suffered stroke or TIA (event rate 7.9 per 100 person years, 95% confidence interval (CI) 5.5–10.4), 26 in the posterior circulation (event rate 4.8 per 100 person years, 95% CI 3.0–6.7). The diagnosis was not associated with follow-up cerebrovascular events. In multivariate models testing multiple potential determinants, only the presentation mode was consistently associated with the diagnosis and stroke risk: patients who presented because of vertigo (rather than reporting vertigo when they presented for other reasons) had a significantly higher risk for future stroke or TIA (p = 0.028, event rate 13.4 vs. 5.4 per 100 person years) and for future posterior circulation stroke or TIA (p = 0.044, event rate 7.8 vs. 3.5 per 100 person years).
Conclusions: We here report for the first time follow-up stroke rates in patients with transient isolated vertigo. In such patients, the identification of those with cerebrovascular origin remains difficult, and presentation mode was found to be the only consistent risk factor. Confirmation in an independent prospective sample is needed.
Functional imaging studies using BOLD contrasts have consistently reported activation of the supplementary motor area (SMA) both during motor and internal timing tasks. Opposing findings, however, have been shown for the modulation of beta oscillations in the SMA. While movement suppresses beta oscillations in the SMA, motor and non-motor tasks that rely on internal timing increase the amplitude of beta oscillations in the SMA. These independent observations suggest that the relationship between beta oscillations and BOLD activation is more complex than previously thought. Here we set out to investigate this rapport by examining beta oscillations in the SMA during movement with varying degrees of internal timing demands. In a simultaneous EEG-fMRI experiment, 20 healthy right-handed subjects performed an auditory-paced finger-tapping task. Internal timing was operationalized by including conditions with taps on every fourth auditory beat, which necessitates generation of a slow internal rhythm, while tapping to every auditory beat reflected simple auditory-motor synchronization. In the SMA, BOLD activity increased and power in both the low and the high beta band decreased expectedly during each condition compared to baseline. Internal timing was associated with a reduced desynchronization of low beta oscillations compared to conditions without internal timing demands. In parallel with this relative beta power increase, internal timing activated the SMA more strongly in terms of BOLD. This documents a task-dependent non-linear relationship between BOLD and beta-oscillations in the SMA. We discuss different roles of beta synchronization and desynchronization in active processing within the same cortical region.
Reactive oxygen species are produced transiently in response to cell stimuli, and function as second messengers that oxidize target proteins. Protein-tyrosine phosphatases are important reactive oxygen species targets, whose oxidation results in rapid, reversible, catalytic inactivation. Despite increasing evidence for the importance of protein-tyrosine phosphatase oxidation in signal transduction, the cell biological details of reactive oxygen species-catalyzed protein-tyrosine phosphatase inactivation have remained largely unclear, due to our inability to visualize protein-tyrosine phosphatase oxidation in cells. By combining proximity ligation assay with chemical labeling of cysteine residues in the sulfenic acid state, we visualize oxidized Src homology 2 domain-containing protein-tyrosine phosphatase 2 (SHP2). We find that platelet-derived growth factor evokes transient oxidation on or close to RAB5+/ early endosome antigen 1− endosomes. SHP2 oxidation requires NADPH oxidases (NOXs), and oxidized SHP2 co-localizes with platelet-derived growth factor receptor and NOX1/4. Our data demonstrate spatially and temporally limited protein oxidation within cells, and suggest that platelet-derived growth factor-dependent “redoxosomes,” contribute to proper signal transduction.
Bone losses are common as a consequence of unloading and also in patients with chronic obstructive pulmonary disease (COPD). Although hypoxia has been implicated as an important factor to drive bone loss, its interaction with unloading remains unresolved. The objective therefore was to assess whether human bone loss caused by unloading could be aggravated by chronic hypoxia.
In a cross-over designed study, 14 healthy young men underwent 21-day interventions of bed rest in normoxia (NBR), bed rest in hypoxia (HBR), and hypoxic ambulatory confinement (HAmb). Hypoxic conditions were equivalent to 4000 m altitude. Bone metabolism (NTX, P1NP, sclerostin, DKK1) and phospho-calcic homeostasis (calcium and phosphate serum levels and urinary excretion, PTH) were assessed from regular blood samples and 24-hour urine collections, and tibia and femur bone mineral content was assessed by peripheral quantitative computed tomography (pQCT).
Urinary NTX excretion increased (P < 0.001) to a similar extent in NBR and HBR (P = 0.69) and P1NP serum levels decreased (P = 0.0035) with likewise no difference between NBR and HBR (P = 0.88). Serum total calcium was increased during bed rest by 0.059 (day D05, SE 0.05 mM) to 0.091 mM (day D21, P < 0.001), with no additional effect by hypoxia during bed rest (P = 0.199). HAmb led, at least temporally, to increased total serum calcium, to reduced serum phosphate, and to reduced phosphate and calcium excretion.
In conclusion, hypoxia did not aggravate bed rest-induced bone resorption, but led to changes in phospho-calcic homeostasis likely caused by hyperventilation. Whether hyperventilation could have mitigated the effects of hypoxia in this study remains to be established.
This study introduces a simple generic model, the Generic Pest Forecast System (GPFS), for simulating the relative populations of non-indigenous arthropod pests in space and time. The model was designed to calculate the population index or relative population using hourly weather data as influenced by evelopmental rate, high and low temperature mortalities and wet soil moisture mortality. Each module contains biological parameters derived from controlled experiments. The hourly weather data used for the model inputs were obtained from the National Center of Environmental Prediction Climate Forecast System Reanalysis (NCEP-CFSR) at a 38 km spatial resolution. A combination of spatial and site-specific temporal data was used to validate the GPFS models. The oriental fruit fly, Bactrocera dorsalis (Hendel), was selected as a case study for this research because it is climatically driven and a major pest of fruit production. Results from the GPFS model were compared with field B. dorsalis survey data in three locations: 1) Bangalore, India; 2) Hawaii, USA; and 3) Wuhan, China. The GPFS captured the initial outbreaks and major population peaks of B. dorsalis reasonably well, although agreement varied between sites. An index of agreement test indicated that GPFS model simulations matched with field B. dorsalis observation data with a range between 0.50 and 0.94 (1.0 as a perfect match). Of the three locations, Wuhan showed the highest match between the observed and simulated B. dorsalis populations, with indices of agreement of 0.85. The site-specific temporal comparisons implied that the GPFS model is informative for prediction of relative abundance. Spatial results from the GPFS model were also compared with 161 published observations of B. dorsalis distribution, mostly from East Asia. Since parameters for pupal overwintering and survival were unknown from the literature, these were inferred from the distribution data. The study showed that GPFS has promise for estimating suitable areas for B. dorsalis establishment and potentially other non-indigenous pests. It is concluded that calibrating prediction models with both spatial and sitespecific temporal data may provide more robust and reliable results than validations with either data set alone.
Decision tools have been advocated to assist the prioritization of management areas for preventing and mitigating exotic invasions into native ecosystems. Currently, most tools have been created for specific invaders/regions and are thus often not sufficient to address the complex range of invasion scenarios that managers encounter. As exotic invasions continue to be a major issue, science-based, information-driven tools are pressingly needed. In this study, we explore the potential of utilizing the Analytic Hierarchy Process (AHP), one of the information-driven tools, to flexibly prioritize various invasion scenarios by incorporating a broad spectrum of management data. We tested the flexibility of the AHP management tool with two distinct invasion-stage-specific prioritizations for Amur honeysuckle (Lonicera maackii). The AHP tool successfully created two management prioritizations from contrasting invasion scenarios of established Amur honeysuckle invasion versus a hypothetical scenario of newly invading populations. The flexibility of AHP allowed users to alter input based on the stage of invasion in each scenario. In the established scenario, management priority was assigned to removing Amur honeysuckle from the most ecologically significant areas. For the new invasion scenario, priority was shifted to removing the invader from areas of most recent invasions. The two contrasting prioritizations demonstrate the flexibility of AHP as a management tool. We conclude that the flexible AHP tool could be useful for prioritizing management of exotic plant invasions.
Impacts of alien species on human health have recently become a major issue in medical research and invasion ecology, but comprehensive assessments of this subject are largely lacking. Here, we provide a literature review of alien species with public health impacts in Europe based on a systematic search in the Thomson Reuters Web of Science. We detected 77 relevant articles, of which 21 were reviews and 56 were original research articles. The taxonomic focus was on vascular plants (n=31 articles) and dipterans (n=25 articles). The original research articles mainly covered the spread of the study species, while early invasion stages (introduction, establishment) as well as impact and management were less investigated. Alien species of health concern in Europe are mostly introduced as contaminants, and mostly originate from climatically similar regions of the Northern Hemisphere. In those cases (36% of all articles) when information on the trend in range and abundance was provided, this trend was mostly increasing. We detected little information on the severity of the impacts (two articles) and the interaction with climate change (three articles). In 15 original articles (28%) specific management measures were suggested, in only one article the socioeconomic costs were assessed. We conclude that European research on human health impacts of alien species is biased towards few species, and that several important aspects such as early invasion stages, severity of impact and its temporal trends, and the scale of the socioeconomic costs caused are poorly understood. Interdisciplinary projects bridging gaps between ecologists medical researchers, socioeconomists and public health authorities are required to link alien species to severity and trends of impacts, which is a crucial requisite for risk assessment and decision making.
Hemidactylus frenatus is an Asian gecko species that has invaded many tropical regions to become one of the most widespread lizards worldwide. This species has dispersed across the Pacific Ocean to reach Hawaii and subsequently Mexico and other Central American countries. More recently, it has been reported from northwestern South America. Using 12S and cytb mitochondrial DNA sequences I found that South American and Galápagos haplotypes are identical to those from Hawaii and Papua New Guinea, suggesting a common Melanesian origin for both Hawaii and South America. Literature records suggest that H. frenatus arrived in Colombia around the mid-‘90s, dispersed south into Ecuador in less than five years, and arrived in the Galápagos about one decade later.
Ambrosia artemisiifolia is an invasive annual herb infamous for the high allergenicity of its pollen, which is related to increasing medical costs. Additionally, it can cause serious yield losses as agricultural weed. Common ragweed seeds accumulate in the soil and can remain therein viable for decades, which poses a problem for the sustainable management of these populations. A long term management should thus target a reduction of the soil seed bank. We observed the influence of four different mowing regimes on the ragweed soil seed bank at six roadside populations in eastern Austria. The mowing regimes were based on methods from common roadside management practice and specifically adapted to reduce seed production. After three years of application, the soil seed bank was indeed reduced by 45 to 80 percent through three of the four mowing regimes tested. Therefore, we suggest that the best mowing regime for the most effective reduction of the size of the soil seed bank is the one consisting of one cut just after the beginning of female flowering (around the 3rd week of August in Eastern Central Europe), followed by a second cut 2–3 weeks later.