Standortökologie des in der Schweiz stark gefährdeten Moor-Veilchens (Viola persicifolia auct.)

Der Klimawandel, der Nährstoffeintrag und das Aufkommen von invasiven Neophyten sind einige von vielen Gründen, wieso die Biodiversität in der Schweiz bedroht ist. Viele Arten sind nicht an lange Trockenperioden, heftige Überschwemmungen und die Konkurrenz durch nährstoffverträglichere Arten und Neophyten angepasst. Das Moor-Veilchen (Viola persicifolia auct. non Schreb., Syn. V. stagnina Kit.) gehört zu den Arten, die in der Schweiz aus verschiedenen Gründen stark bedroht (EN) sind. Heute gibt es in der Schweiz sechs Hauptverbreitungsorte von V. persicifolia, die sich vor allem in den Kantonen Aargau, Zürich, Neuenburg und Genf befinden. Im Kanton Zürich wird V. persicifolia seit 2004 gemäss einem Aktionsplan gefördert. Der Kanton Aargau hat im vergangenen Jahr erneut einen solchen erarbeitet. Trotz verschiedener Wiederansiedlungen in diesen beiden Kantonen in den vergangenen Jahren konnte die Art nicht zufriedenstellend gefördert und die Populationen nicht merklich vergrössert werden. Erhaltungs- und Fördermassnahmen sind mit einem hohen Aufwand verbunden. Da die Art und ihre Standortansprüche bisher nicht ausreichend erforscht sind, ist es wichtig, diese besser kennenzulernen. Nur so können Massnahmen zielgerichtet umgesetzt werden. Im Rahmen dieser Arbeit sollen durch Felduntersuchungen wichtige Hinweise erarbeitet werden, die mögliche Gründe für ein Gelingen oder Scheitern von Wiederansiedlungen liefern sollen. Dazu wurden Orte aufgesucht, an denen V. persicifolia autochthon vorkommt, an denen sie erfolgreich angesiedelt wurde oder nach einer Wiederansiedlung wieder verschwunden ist. Neben quantitativen Vegetationsaufnahmen wurden verschiedene Umweltfaktoren untersucht. Die eigenen Daten wurden für die Auswertung durch 462 europäische Vegetationsaufnahmen ergänzt. Die Analysen haben bei den meisten untersuchten Parametern keine signifikanten Unterschiede zwischen autochthonen Populationen, erfolgreichen und erfolglosen Wiederansiedlungen ergeben. Auch die Pflegemassnahmen der Schweizer Gebiete mit Populationen von V. persicifolia liefern keine wichtigen Hinweise, da an den meisten Orten eine jährliche Herbstmahd erfolgt. Die internationalen Daten unterscheiden sich hinsichtlich der Zeigerwerte und Begleitarten wesentlich von den Daten aus der Schweiz. Als Fördermöglichkeiten werden eine regelmässige Mahd und Störungen sowie das Entfernen von Pflanzen starken Wachstums erachtet. Da V. persicifolia in der Vergangenheit einige Male nach Abschürfungen des Oberbodens spontan auftrat, wird auch dies als Möglichkeit betrachtet, die Populationen zu erhalten. Soll V. persicifolia langfristig überleben, müsste weiterhin Geld in Fördermassnahmen und Wiederansiedlungen investiert werden. Bevor diese Massnahmen umgesetzt würden, bedarf es weiteren Untersuchungen zur Ökologie und den Standortansprüchen dieser Art. Dennoch bleibt es fraglich, ob V. persicifolia in Anbetracht der äusseren Umstände wirklich eine Chance hat, zu überleben.Climate change, nutrient inputs and the emergence of invasive neophytes are some of the many reasons why biodiversity is threatened in Switzerland. Many species are not adapted to long periods of drought, heavy flooding and competition from more nutrient-tolerant species and neophytes. The fen violet (Viola persicifolia auct.non Schreberi, Syn. Viola stagnina) is one of the species that are endangered (IUCN: “EN”) in Switzerland for various reasons. Today, there are six main distribution sites in Switzerland, mainly in the cantons of Aargau, Zurich, Neuchâtel and Geneva. In the canton of Zurich, Viola persicifolia has been supported since 2004 according to an action plan. The canton of Aargau also developed another one last year. Despite various reintroduction efforts in these two cantons in recent years, the species has not been supported satisfactorily and the populations have not increased noticeably. Conservation and support measures require a high level of effort. As the species and its habitat requirements have not been sufficiently researched so far, more research needs to focus on them. Only then measures can be implemented in a targeted manner. In the context of this work, field studies were carried out to obtain important information on possible reasons for the success or failure of reintroduction efforts. For this reason, sites were visited where V. persicifolia either occurs autochthonously, where it was successfully reintroduced, or where it disappeared again after reintroduction. In addition to quantitative vegetation surveys, various environmental factors were investigated. The own data was supplemented by 462 European vegetation surveys for the analysis. However, the analyses did not reveal any significant differences between autochthonous, successful and unsuccessful reintroductions for most of the parameters examined. Only the international data differs significantly from the data from Switzerland. The maintenance measures in Swiss areas with populations of V. persicifolia do not provide any important information either, since in most places annual autumn mowing is carried out. Regular mowing and disturbance, as well as the removal of plants with strong growth, are considered to be support options. Since V. persicifolia has appeared spontaneously a few times in the past after topsoil scraping, this is also considered a possibility to maintain populations. If V. persicifolia is to survive in the long term, money would have to continue to be invested in support measures and reintroductions. However, before these measures can be implemented, further research on the ecology and habitat requirements of this species is needed. Nevertheless, it remains questionable whether V. persicifolia really has a chance to survive in the long-term in view of the external circumstances

Decisions to stay and migrate in Algeria, Ethiopia and Nigeria: Scoping studies for the PACES project

Knowledge and understanding of people's decision to migrate is critical for policymakers' ability to developmigration policies. The EU-funded PACES project – Making migration and migration policy decisions amidstsocietal transformations focuses on two parallel research components: the factors shaping migration decision-making and the mechanisms supporting migration policies.The project will combine theoretical and empirical knowledge from several academic disciplines andmethodological paradigms to systematically investigate the interactions between migration decisions, policies,and broader social transformation. PACES will draw on data collected in Algeria, Ethiopia, Italy, Libya, Nigeria,Slovakia, and Spain to elaborate a heuristic model that identifies different constellations of conditions thatinfluence decisions to stay and migrate at various stages of individual life trajectories and migrant journeys. Thisreport presents three scoping studies carried out to examine and select the six research locations(secondary cities) in Algeria, Ethiopia and Nigeria.The scoping studies considered nine locations from which the six research areas are selected at the end of thisreport. These scoping studies were conducted for the research component, also referred to as workpackage (WP), that studies how people make decisions to stay and migrate to/in/from Algeria, Ethiopia,and Nigeria. Within this component, we explore how people’s decisions to stay and migrate are influenced bysocietal changes, individual life experiences and migration policies over time and as people move acrossdifferent locations. We pay particular attention to the role of people's perceptions of their social and personalsituation, as well as their values and expectations, as determining factors in decisions to stay or emigrate.1Algeria, Ethiopia and Nigeria are countries of origin, transit and destination, which makes it possible to studythe factors that determine decisions to stay and migrate among different populations: 1) residents who decideto stay or who may aspire to migrate, 2) migrants on the move and 3) people settled in these countries. Thecombination of all these characteristics makes these three countries suitable for exploring the links betweenlong-term social transformations and migration decision-making processes before the onset of migration andthroughout the migratory journey.Although the characteristics of these three countries at national level are important, this project movesfrom the national context to the regional and municipal context. To do this, it focuses on specific secondarycities, their historical development, including their migration history and their role in the national mobilitydynamics. In sum, this WP seeks to highlight how long-term societal changes in the selected secondary citiesshapes the perceptions, values, personal expectations and life and migration aspirations of residents andmigrants

Processable Fully Aromatic Quinoline-based Polymers

Quinoline-based homo- and copolymers have been synthesized by the acid-catalyzed Friedlaender condensation between bis(o-aminoketone)s and silicon-containing bis(ketomethylene) monomers. The polymers contain quaternary silicon atoms and are fully aromatic; they show improved solubility compared to known polyquinolines with approximately unchanged softening and decomposition temperatures of the final material. A new solubilization method was developed for these materials. In addition two block copolymers based on an aramid block containing fluorene cardo units and polyquinoline were prepared

STARCH SYNTHASE5, a Noncanonical Starch Synthase-Like Protein, Promotes Starch Granule Initiation in Arabidopsis

What determines the number of starch granules in plastids is an enigmatic aspect of starch metabolism. Several structurally and functionally diverse proteins have been implicated in the granule initiation process in Arabidopsis (Arabidopsis thaliana), with each protein exerting a varying degree of influence. Here, we show that a conserved starch synthase-like protein, STARCH SYNTHASE5 (SS5), regulates the number of starch granules that form in Arabidopsis chloroplasts. Among the starch synthases, SS5 is most closely related to SS4, a major determinant of granule initiation and morphology. However, unlike SS4 and the other starch synthases, SS5 is a noncanonical isoform that lacks catalytic glycosyltransferase activity. Nevertheless, loss of SS5 reduces starch granule numbers that form per chloroplast in Arabidopsis, and ss5 mutant starch granules are larger than wild-type granules. Like SS4, SS5 has a conserved putative surface binding site for glucans and also interacts with MYOSIN-RESEMBLING CHLOROPLAST PROTEIN, a proposed structural protein influential in starch granule initiation. Phenotypic analysis of a suite of double mutants lacking both SS5 and other proteins implicated in starch granule initiation allows us to propose how SS5 may act in this process. © 2020 American Society of Plant Biologists.ISSN:1532-298XISSN:1531-298XISSN:1040-465

MFP1 defines the subchloroplast location of starch granule initiation

Starch is one of the major carbohydrate storage compounds in plants. The biogenesis of starch granules starts with the formation of initials, which subsequently expand into granules. Several coiled-coil domain-containing proteins have been previously implicated with the initiation process, but the mechanisms by which they act remain largely elusive. Here, we demonstrate that one of these proteins, the thylakoid-associated MAR-BINDING FILAMENT-LIKE PROTEIN 1 (MFP1), specifically determines the subchloroplast location of initial formation. The expression of MFP1 variants “mis”-targeted to specific locations within chloroplasts in Arabidopsis results in distinctive shifts in not only how many but also where starch granules are formed. Importantly, “re” localizing MFP1 to the stromal face of the chloroplast’s inner envelope is sufficient to generate starch granules in this aberrant position. These findings provide compelling evidence that a single protein MFP1 possesses the capacity to direct the initiation and biosynthesis machinery of starch granules.ISSN:0027-8424ISSN:1091-649

Two distinct phases of chloroplast biogenesis during de-etiolation in Arabidopsis thaliana

Dynamics of chloroplast biogenesis Impact statement: Serial Block Face Scanning Electron Microscopy (SBF-SEM) associated with biomolecular analysis show that chloroplast differentiation proceeds by distinct 'Structure Establishment' and 'Chloroplast Proliferation' phases, each with differential protein and lipid regulation

A multifaceted analysis reveals two distinct phases of chloroplast biogenesis during de-etiolation in arabidopsis

Light triggers chloroplast differentiation whereby the etioplast transforms into a photosynthesizing chloroplast and the thylakoid rapidly emerges. However, the sequence of events during chloroplast differentiation remains poorly understood. Using Serial Block Face Scanning Electron Microscopy (SBF-SEM), we generated a series of chloroplast 3D reconstructions during differentiation, revealing chloroplast number and volume and the extent of envelope and thylakoid membrane surfaces. Furthermore, we used quantitative lipid and whole proteome data to complement the (ultra)structural data, providing a time-resolved, multi-dimensional description of chloroplast differentiation. This showed two distinct phases of chloroplast biogenesis: an initial photosynthesis-enabling ‘Structure Establishment Phase’ followed by a ‘Chloroplast Proliferation Phase’ during cell expansion. Moreover, these data detail thylakoid membrane expansion during de-etiolation at the seedling level and the relative contribution and differential regulation of proteins and lipids at each developmental stage. Altogether, we establish a roadmap for chloroplast differentiation, a critical process for plant photoautotrophic growth and survival