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We performed a survey of grassland communities in the Ukrainian Carpathians with the aim of: (1) syntaxonomically classifying the meso- and subxerophilous grassland vegetation; (2) analysing the main gradients in their species composition; (3) estimating the effect of selected environmental factors on grassland species composition; (4) assessing the species richness of vascular plants and bryophytes in relation to the measured environmental variables. We collected 46 phytosociological relevés during the growing seasons of 2010 and 2011. Species composition and species richness were studied at two spatial scales (1 m² and 16 m²) in relation to soil parameters (soil depth, pH (KCl), content of P, K, Mg, N and C), management regime (mowing, grazing, ploughing in the past and burning), and other factors (altitude, litter cover, open soil, inclination, solar radiation and animal excrement). Seven grassland types were distinguished belonging to 3 classes and 4 alliances, namely the Nardetea strictae including the Violion caninae (mesic pastures at altitudes of 400–600 m mostly on moderate slopes) and the Nardo strictae-Agrostion tenuis (grasslands on moderate slopes at altitudes of 700–900 m usually managed by mowing and grazing the aftermath); the Molinio-Arrhenatheretea, including the Arrhenatherion elatioris (submontane grasslands originated mostly on former fields after their abandonment in the past) and the Cynosurion cristati (intensive pastures); and the Festuco-Brometea including the Cirsio-Brachypodion pinnati (abandoned grasslands dominated by Brachypodium pinnatum and Inula salicina). Detrended correspondence analysis indicated that the major compositional turnover was related to altitude and soil reaction. A canonical correspondence analysis confirmed that altitude had the strongest effect on species composition in the analysed dataset, followed by management treatments (former ploughing, grazing intensity). For vascular plant species richness, regression tree analysis identified grazing intensity as the most important predictor at the 1 m² scale. At the 16 m² scale, soil humus content was evaluated as the most important predictor of vascular plant species richness, followed by litter cover and grazing intensity. The number of bryophytes was not determined by the studied environmental factors at either of the two spatial scales. Although the number of analysed relevés in this study was limited, our results significantly contribute to the understanding of submontane grasslands in the Ukrainian Carpathians.
Compared to other grassland types across Slovakia, dry grasslands harbour species-rich and specialised ant communities. High diversity and species richness of ants may be seen as a consequence of (i) the specific structure of dry grassland vegetation, (ii) long-term ecological stability, and (iii) currently low or absent management-induced disturbance. With special regard to dry grasslands, we report on structural characteristics of vegetation and low-disturbance regime, which contribute to ant assemblage structure. Our study was carried out in the Štiavnické Vrchy Mts. (Central Slovakia), a region with a historically well-developed grassland area. We established a set of 25 research plots within southorientated grassland habitats representing five different grassland types: wet managed and wet abandoned grasslands, mesic managed and mesic abandoned grasslands (Arrhenatherion elatioris), and dry abandoned grassland habitats (Asplenio-Festucion glaucae). Each habitat type was represented by five plots. At each plot, a set of ten pitfall traps was used to sample ground-foraging ant assemblages. Around each trap, structural characteristics of vegetation and microhabitat were assessed. Dry grasslands were shown to have a specific microhabitat structure, characterised by the presence of a well-developed moss and lichen layer, exposed bedrock, bare soil, and significantly lower, although species-rich vege - tation. Besides the specific microhabitat structure, the absence of management may have contributed to the distinctiveness of these ant assemblages compared to those associated with other grassland categories. Ant assemblages were more species-rich, and the activity of ants was higher in recently abandoned grassland habitats. The effect of abandonment was quite opposite for plants, whose species-richness was, contrary to ants, higher within managed sites.
Prioritisation of high-impact species is becoming increasingly important for management of introduced species (‘neobiota’) because of their growing number of which, however, only a small fraction has substantial impacts. Impact scores for prioritising species may be affected by the type of effect model used. Recent studies have shown that environmental co-variation and non-linearity may be significant for effect models of biological invasions. Here, we test for differences in impact scores between simple and complex effect models of three invasive plant species (Heracleum mantegazzianum, Lupinus polyphyllus, Rosa rugosa). We investigated the effects of cover percentages of the invasive plants on species richness of invaded communities using both simple linear effect models (‘basic models’) and more complex linear or nonlinear models including environmental co-factors (‘full models’). Then, we calculated impact scores for each invasive species as the average reduction of species richness predicted by basic and full effect models. All three non-native species had negative effects on species richness, but the full effect models also indicated significant influence of habitat types. Heracleum mantegazzianum had uniform linear effects in all habitats, while effects of L. polyphyllus interacted strongly with habitat type, and R. rugosa showed a marked non-linear relationship. Impact scores were overestimated by basic effect models for H. mantegazzianum and R. rugosa due to disregard of habitat effects and non-linearity, respectively. In contrast, impact of L. polyphyllus was underestimated by the basic model that did not account for the strong interaction of invader cover and habitat type. We conclude that simple linear models will often yield inaccurate impact scores of non-native species. Hence, effect models should consider environmental co-variation and, if necessary, non-linearity of the effects of biological invasions on native ecosystems.
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.
In the face of increasing invasions and limited resources, appropriate management of invasive species requires prioritisation of species for management action. This process often relies on knowledge of species specific impacts. However, as studies explicitly measuring impact of marine alien species are rare, prioritisation of management actions is often based on studies from outside the geographic area of interest. Further, few impact studies account for context dependency (e.g. seasonal variability or distinct environmental regimes), raising the question of how transferrable knowledge about the impact of a species is between invaded ranges. This study addressed this question by using the widespread invasive solitary ascidian Ciona robusta as a case study for assessing impacts across two invaded regions: South Africa and California, USA. We replicated a previously conducted experiment from California that showed that C. robusta depresses local species richness in San Francisco Bay. Our South African experiment showed no effect of C. robusta on species richness, the Shannon-Weiner diversity index or community composition, despite experiments being carried out over two years and at two depths. While these results may reflect strong density dependency in the impact of C. robusta, they serve to highlight context dependency in invasive species impacts. This suggests that until studies of impact in marine systems become common place, context dependency should be explicitly addressed as a source of uncertainty during the prioritisation of species for management action.
As legislation, research and management of invasive alien species (IAS) are not fully coordinated across countries or different stakeholder groups, one approach leading to more or less standardized activities is based on producing lists of prominent IAS that attain high level of concern and are a subject of priority monitoring and management. These so-called Black, Grey and Watch (alert) Lists represent a convenient starting point for setting priorities in prevention, early warning and management systems. It is important that these lists be based on transparent and robust criteria so as to accommodate interests and perception of impacts by groups of concerned authorities and stakeholders representing sectors as diverse as, e.g. forestry, horticulture, aquaculture, hunting, and nature conservation, and to justify possible trade restrictions. The principles for blacklisting need to be general enough to accommodate differences among taxonomic groups (plants, invertebrates, vertebrates) and invaded environments (e.g. aquatic, terrestrial, urban, suburban, seminatural), and must take into account invasion dynamics, the impact the IAS pose, and management strategies suitable for each particular invader. With these assumptions in mind, we synthesize available information to present Black, Grey and Watch Lists of alien species for the Czech Republic, with recommended categorized management measures for land managers, policy makers and other stakeholders. We took into account differences in the listed species’ distribution, invasion status, known or estimated environmental impact, as well as possible management options, and apply these criteria to both plants and animals. Species with lower impact, but for which some level of management and regulation is desirable, are included on the Grey List. Some potentially dangerous species occurring in European countries with comparable climatic conditions, as well as those introduced in the past but without presently known wild populations in the Czech Republic, are listed on the Watch list. In total, there are 78 plant and 39 animal species on the Black List, 47 and 16 on the Grey List, and 25 and 27, respectively, on the Watch List. The multilayered approach to the classification of alien species, combining their impacts, population status and relevant management, can serve as a model for other countries that are in process of developing their Black Lists.
In Borstgrasrasen (Nardetalia) des Werra-Meißner-Gebietes (Nordhessen, Südniedersachsen) wurden 2012 nach 25 Jahren auf möglichst gleichen Untersuchungsflächen (quasi-Dauerflächen) Wiederholungsaufnahmen angefertigt, um den gegenwärtigen Zustand bzw. Veränderungen in diesem prioritären FFH-Lebensraumtyp zu erfassen. Es wurden insgesamt 61 Flächen untersucht. Neben der Artenzusammensetzung wurden auch Bodenparameter (pH, C/N-Verhältnis, Mächtigkeit der organischen Auflage) und die Nutzung erfasst.
Bei der Wiederholungsaufnahme 2012 waren, abgesehen von einer Aufforstungsfläche, noch auf allen Flächen Arten der Borstgrasrasen vorhanden. Die Flächen wurden 2012 überwiegend genutzt oder gepflegt, während 1986/87 Brachflächen noch bei weitem dominierten. Eine Düngung der Flächen erfolgte nicht. Trotz dieser generell günstigen Nutzungssituation lässt sich ein genereller Trend zur Eutrophierung feststellen, der sich hinsichtlich Artenzahl und Deckung in einer Zunahme von Arten des Wirtschaftsgrünlandes (Molinio-Arrhenatheretea) bei gleichzeitiger Abnahme der Borstgrasrasen-Kennarten äußert. Auch die Artenzahlen der übrigen Magerkeitszeiger nahmen im Mittel ab, während Verbrachungszeiger im Allgemeinen zunahmen. Eine Veränderung der Gesamtartenzahl war nicht festzustellen. Die mittleren Zeigerwerte spiegeln die Verschiebungen im Arteninventar durch erhöhte mittlere Reaktions- und Stickstoffzahlen wider. Strukturell hat in den vergangenen 25 Jahren vor allem eine generelle Zunahme der Moosschichtdeckung und eine Ausbreitung der Sträucher auf Brachflächen stattgefunden. Bei den Bodenparametern waren 2012 eine signifikante Erhöhung der pH-Werte, eine Einengung der C/N-Verhältnisse und eine Abnahme der Mächtigkeit der organischen Auflage (Of) feststellbar. Regressionsmodelle zeigen, dass dabei die Zunahme von Arten des Wirtschaftsgrünlandes direkt mit den ansteigenden pH-Werten zusammen hing, während die Veränderungen bei den Kennarten eher vom Ausgangs-C/N-Verhältnis, teilweise auch von der Entwicklung der organischen Auflage und der Nutzung abhängig waren. Die vorgefundenen Veränderungen werden vor dem Hintergrund möglicher Gefährdungsszenarien (Brache, Eutrophierung, Bodenversauerung, Klimawandel) diskutiert. Angesichts des unerwarteten Befundes einer Eutrophierung bei gleichzeitig nachlassender Bodenversauerung, wird die Hypothese aufgestellt, dass der seit den 1990er-Jahren erfolgte Rückgang der Schwefeldepositionen mit nachfolgender Erholung der Boden-pH-Werte und nachlassender Stressbelastung, z. B. durch Ammonium-Toxizität, die Veränderungen ausgelöst haben könnte. Außerdem deuten die Ergebnisse auf eine zumindest teilweise zu geringe Nutzungs- bzw. Pflegeintensität bzw. zu späte Nutzungstermine. Möglicherweise führt der erhöhte Eutrophierungsdruck hier auch zu verstärkten Anforderungen an das Management der Flächen. Eindeutige Indizien für klimabedingte Veränderungen im Arteninventar ließen sich nicht finden. Indirekte Effekte über eine erwärmungsbedingte Förderung der Mineralisationsraten oder ein ursächlicher Zusammenhang zwischen höheren Wintertemperaturen und der Zunahme der Moosdeckung lassen sich jedoch nicht ausschließen.
Seit 1890 wird die aus dem westlichen Nordamerika stammende Fabacee Lupinus polyphyllus Lindl. (Stauden-Lupine) in Deutschland beobachtet. Ihre großflächigsten Vorkommen in Deutschland finden sich derzeit in der Hohen Rhön im Gebiet Leitgraben/Elsgellen (407 ha: 1998 10,6 % Lupinus-Bedeckung). Dort werden fast alle Wiesen mit Auflagen des Bayerischen Vertragsnaturschutzprogramms bewirtschaftet. Dies bedeutet, zeitlich gestaffelte Pflegetermine zwischen 10. Juli und 31. Oktober (Abschluss der Pflegearbeiten), die den Zeitraum der Samenbildung von Lupinus vollständig erschließen. Nachweisbar ist, dass dort, wo innerhalb der Vertragsnaturschutzflächen Heugewinnung die primäre Motivation für die Nutzung ist - dies bedeutet Nutzung zum frühest möglichen Zeitpunkt - keine Lupinus-Etablierung nachweisbar ist! Neben rechtzeitiger Mahd ist Beweidung mit (Rhön-)Schafen geeignet, die Ver- und Ausbreitung von Lupinus einzudämmen. Auch dafür gilt, dass sie vor der Samenreife (ab Anfang Juli) von Lupinus durchzuführen ist, da reife Lupinus-Samen durch Schafe endozooisch ausgebreitet werden. Vegetationsaufnahmen von Kleinseggenrieden (Caricetum fuscae), Borstgrasrasen (Polygalu-Nardetum) und Goldhaferwiesen (Geranio-Trisetetum), in denen Lupinus polyphyllus mit höheren Deckungsgraden (> 25 %) vorkommt, belegen, dass die niedrigwüchsigen Arten der Krautschicht zurückgedrängt werden. Parallel dazu nehmen die kräftige Horste ausbildenden Gräser Poa chaixii und Deschampsia cespitosa zu. Eine Trennartengruppe mit den Ruderalarten Cerastium glomeratum, Galium aparine agg., Galeopsis tetrahit, Cirsium arvense und Urtica dioica charakterisiert die Lupinus-Fazies. Die Konkurrenzkraft der Dominanzbestände mit Lupinus erklärt sich über die Biomasseverteilung in Form einer umgekehrten Pyramide, die über Bestandeshöhe (zwischen 70 und 110 cm) und dichte Belaubung stark beschattend auf tiefere Vegetationsschichten (< 30 cm) wirkt, so dass deren Arten ausdünnen, wenn sie nicht die ausreichende Plastizität im Höhenwachstum besitzen, um mit Lupinus mitzuhalten. Auch andere Dominanzbestände-aufbauende Arten wie Impatiens glandulifera, Heracleum mantegazzianum und Reynoutria ssp. besitzen diese Eigenschaft und können aufgrund ihrer Wuchshöhe sogar die Funktion einer fehlenden Strauchschicht übernehmen.
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.
Introduction: In patients with severe pelvic ring injuries, exsanguination still is the leading cause of death in the early post-injury phase. While mechanical pelvic ring stabilization and pre-peritoneal pelvic packing are mainly addressing venous bleeding, angio-embolization aims to control arterial bleeding. The goal of the present study was to evaluate the rate of postoperative angio-embolization after mechanical pelvic ring injury stabilization and pre-peritoneal pelvic packing. Bleeding sources detected in the angiography and the patient's outcome were investigated. Patients and Methods: Retrospective observational cohort study at a single academic level I trauma center, reviewing all patients with pelvic ring injuries admitted from 01/2010 to 12/2019. Patients with emergent mechanical pelvic ring stabilization (supraacetabular external fixator and/or pelvic C-clamp) and direct pre-peritoneal pelvic packing were further analyzed. Patients that underwent postoperative angio-embolization were compared with those that did not. All postoperative angio-embolizations were evaluated with regards to bleeding sources and type of embolization. Results: During the study period, a total of 39 patients required immediate mechanical pelvic stabilization and direct pre-peritoneal pelvic packing. Of these, 12 patients (30.8%) underwent a postoperative angio-embolization. The following vessels were identified as bleeding sources: superior gluteal artery (n = 6), obturator artery (n = 2), internal pudendal artery (n = 2), unnamed branches of the internal iliac artery (n = 3). A selective embolization was successful in 11 patients; in 1 patient, an unilateral complete occlusion of the internal iliac artery was performed to control the bleeding. Mean time from hospital admission to the surgical procedure was 52.8 ± 14.7 min and the mean time from admission to angio-embolization was 189.1 ± 55.5 min. The in-hospital mortality rate of patients with angio-embolization was 25.0% (n = 3). Of these, 2 patients died due to multiple organ failure and 1 patient due to severe head injury. Conclusion: Secondary angio-embolization after external pelvic fixation and pre-peritoneal pelvic packing was effective in controlling ongoing bleeding. The most frequently detected bleeding vessel was the superior gluteal artery, which is difficult to surgically address, further highlighting the importance of angio-embolization in the management algorithm.