Abrupt Alnus population decline at the end of the first millennium CE in Europe – The event ecology, possible causes and implications

The study, based on the examination of 70 published and unpublished pollen profiles from Poland and supplementary data from the surrounding regions, shows that an abrupt, episodic Alnus population decline at the end of the first millennium CE was a much more widespread event than has been previously reported, spanning large areas of the temperate and boreal zones in Europe. The data from Poland suggest that the decline was roughly synchronous and most likely occurred between the 9th and 10th centuries, with strong indications for the 10th century. The pollen data indicate that human impacts were not a major factor in the event. Instead, we hypothesize that one or a series of abrupt climatic shifts that caused floods and droughts at the end of the first millennium CE could have initiated this ecological disturbance, leading to a higher vulnerability of the alder trees to a pathogen outbreak. Following current observations of the decline of alder stands in Europe due to a Phytophthora outbreak, we suggest that a similar process may have occurred in the past. This study provides insight into long-term alder (mainly Alnus glutinosa) dynamics in a condition of climate change and illustrates its great resilience, enabling the natural, successful regeneration of alder stands after critical diebacks if environmental conditions improve. Our finding that the Alnus pollen decline reflects a roughly synchronous event indicates that the decline could be used as an over-regional chronostratigraphic marker for 800–1000 CE in pollen diagrams from a large part of the European Lowland.

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A future without stocking? The importance of harvest and river regulation for long-term population viability of migratory salmonids

10.32942/osf.io/ds7u2 ◽

2019 ◽

Cited By ~ 2

Author(s):

Chloé Rebecca Nater ◽

Marlene Wæge Stubberud ◽

Øystein Langangen ◽

Atle Rustadbakken ◽

S. Jannicke Moe ◽

...

Keyword(s):

Size Structure ◽

Human Impacts ◽

Population Decline ◽

Population Viability ◽

Mitigation Measures ◽

Life History Stage ◽

Compensatory Mitigation ◽

Projection Model ◽

Quantitative Models

1. Humans are influencing animal and plant populations both directly (e.g.through harvest) and indirectly by altering environments. For many exploitedspecies, stocking with captive-bred individuals is a common strategy tomitigate negative human impacts and sustain populations over time. However,accumulating knowledge of negative side effects of stocking calls for quantificationof consequences and exploration of sustainable alternatives.2. Evaluating alternative management strategies using quantitative models iscentral to conservation. Here, we investigate the effects of several managementstrategies on a population of landlocked, migratory brown trout (Salmotrutta) inhabiting a large lake and spawning in a dammed river. We assess thepopulation level consequences of terminating a long-term stocking programmeand evaluate whether the loss of artificial recruitment may be compensatedby changes in harvest regulations and/or river habitat improvement.3. We build an integral projection model (IPM) classifying individuals bybody size, life history stage, and location relative to the hydropower damand parameterised it with 50 years of individual-based data supplementedwith literature values. We first analyse the model to assess size, structure,and relative importance of different mortality components across life stagesand locations in trout populations with and without stocking. We theninvestigate potential responses of an unstocked population to managementactions involving different sets of harvest rules, reductions in dam passagemortality, and improvements of spawning habitat below the dam.4. Our model predicts a strong population decline of 12–21% per year in theabsence of stocking. This decline is largely attributed to high harvest mortality,and drastic reductions in fishing pressure thus necessary to ensure populationviability without stocking. Reducing mortality associated with passage of thehydropower dam and restoring spawning areas has only small positive effectson population growth. Nonetheless, these mitigation measures can contributeto population viability when combined with changes in harvest regulations.5. Intensely harvested populations may rely heavily on the addition of captive-bredindividuals, and our results indicate that premature termination of stockingprogrammes can be detrimental without compensatory mitigation measuressuch as harvest reductions and habitat improvements. It is therefore crucialto collect necessary data and assess the impacts of alternative managementstrategies using quantitative models prior to making decisions.

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Long-term changes in kelp forests in an inner basin of the Salish Sea

10.1101/2020.02.13.947309 ◽

2020 ◽

Cited By ~ 1

Author(s):

Helen D. Berry ◽

Thomas F. Mumford ◽

Bart Christiaen ◽

Pete Dowty ◽

Max Calloway ◽

...

Keyword(s):

Human Impacts ◽

Recent Observation ◽

Puget Sound ◽

Kelp Forests ◽

Limited Data ◽

Biogenic Habitat ◽

Conservation Actions ◽

Almost All ◽

Insight Into

AbstractUnderstanding the historical extent of biogenic habitats can provide insight into the nature of human impacts and inform restoration and conservation actions. Kelp forests form an important biogenic habitat that responds to natural and human drivers. Global concerns exist about threats to kelp forests, yet long term information is limited and research suggests that trends are geographically distinct. We examined distribution of the bull kelp Nereocystis luetkeana over 145 years in South Puget Sound (SPS), a semi-protected inner basin in a fjord estuary complex in the northeast Pacific Ocean. We synthesized 48 historical and modern Nereocystis surveys and examined presence/absence within 1-km shoreline segments along 452 km of shoreline. Over the last 145 years, Nereocystis has been documented in 26% of the shoreline segments. Its extent decreased 62% basin-wide between the 1870s and 2017, with extreme losses in the two out of three sub-basins (96% in Central and 83% in West). In recent years, almost all Nereocystis occurred in the East sub-basin. In the majority of segments where Nereocystis disappeared, the most recent observation was 4 decades ago, or earlier. Multiple natural and human factors that are known to impact kelp could have contributed to observed patterns, but limited data exist at the spatial and temporal scale of this study. In some areas, recent environmental conditions approached thresholds associated with decreased kelp performance. Longstanding Nereocystis losses occurred exclusively in areas with relatively low current velocities. Remaining Nereocystis predominantly occurred in areas where circulation is stronger. Exceptions to this pattern demonstrate that additional factors outside the scope of this study contributed to trajectories of Nereocystis persistence or loss.

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Turkish Muslims in a German city: Entrepreneurial and residential self-determination

MIGRATION LETTERS ◽

10.33182/ml.v12i1.252 ◽

2015 ◽

Vol 12 (1) ◽

pp. 1-12

Author(s):

Sarah Hackett

Keyword(s):

Residential Patterns ◽

Academic Literature ◽

Self Employment ◽

German City ◽

Post War ◽

Oral History Interviews ◽

The City ◽

Insight Into ◽

Term Objective

Drawing upon a collection of oral history interviews, this paper offers an insight into entrepreneurial and residential patterns and behaviour amongst Turkish Muslims in the German city of Bremen. The academic literature has traditionally argued that Turkish migrants in Germany have been pushed into self-employment, low-quality housing and segregated neighbourhoods as a result of discrimination, and poor employment and housing opportunities. Yet the interviews reveal the extent to which Bremen’s Turkish Muslims’ performances and experiences have overwhelmingly been the consequences of personal choices and ambitions. For many of the city’s Turkish Muslim entrepreneurs, self-employment had been a long-term objective, and they have succeeded in establishing and running their businesses in the manner they choose with regards to location and clientele, for example. Similarly, interviewees stressed the way in which they were able to shape their housing experiences by opting which districts of the city to live in and by purchasing property. On the whole, they perceive their entrepreneurial and residential practices as both consequences and mediums of success, integration and a loyalty to the city of Bremen. The findings are contextualised within the wider debate regarding the long-term legacy of Germany’s post-war guest-worker system and its position as a “country of immigration”.

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ESTUARINE RECORDS OF LONG-TERM HUMAN IMPACTS ON FLUVIAL SEDIMENT DISCHARGE FROM A LARGE NEW ENGLAND RIVER

10.1130/abs/2016se-273677 ◽

2016 ◽

Author(s):

Justin L. Shawler ◽

◽

Christopher J. Hein

Keyword(s):

New England ◽

Human Impacts ◽

Sediment Discharge ◽

Fluvial Sediment

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Moving Songs

The Oxford Handbook of Musical Repatriation ◽

10.1093/oxfordhb/9780190659806.013.42 ◽

2019 ◽

pp. 590-606

Author(s):

Sally Treloyn ◽

Matthew Dembal Martin ◽

Rona Goonginda Charles

Keyword(s):

Cultural Heritage ◽

Knowledge Transmission ◽

Intercultural Relationships ◽

Cultural Negotiation ◽

Intercultural Collaboration ◽

Present Collection ◽

Intergenerational Knowledge ◽

Early Phases ◽

Insight Into

Repatriation has become almost ubiquitous in ethnomusicological research on Australian Indigenous song. This article provides insights into processes of a repatriation-centered song revitalization project in the Kimberley, northwest Australia. Authored by an ethnomusicologist and two members of the Ngarinyin cultural heritage community, the article provides firsthand accounts of the early phases of a long-term repatriation-centered project referred to locally as the Junba Project. The authors provide a sample of narratives and dialogues that deliver insight into experiences of the work of identifying recordings “in the archive” and cultural negotiation and use of recordings “on Country.” The entanglement of local epistemological frameworks with past and present collection, archival research, repatriation, and dissemination for intergenerational knowledge transmission between spirits, Country, and the living, is explored, showing how recordings move song knowledge from community to archive to community and from generation to generation, and move people in present-day communities. The chapter considers how these “moving songs” allow an interrogation of the fraught endeavor of intercultural collaboration in the pursuit of revitalizing Indigenous song traditions. It positions repatriation as a method that can support intergenerational knowledge transmission and as a method to consider past and present intercultural relationships within research projects and between cultural heritage communities and collecting institutions.

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Chemical stability of oil-infused polyethylene

Journal of Biomaterials Applications ◽

10.1177/0885328220977353 ◽

2020 ◽

pp. 088532822097735

Author(s):

Fedra P Zaribaf ◽

Harinderjit S Gill ◽

Elise C Pegg

Keyword(s):

Vitamin E ◽

Chemical Stability ◽

Antioxidant Properties ◽

Oxidation Stability ◽

Thermal Ageing ◽

Similar Process ◽

Mechanical Degradation ◽

Suitable Material ◽

Thermally Treated

Ultra-high molecular weight polyethylene (UHMWPE) can be made radiopaque for medical imaging applications through the diffusion of an iodised oil-based contrast agent (Lipiodol Ultra Fluid). A similar process is used for Vitamin E incorporated polyethylene which provides antioxidant properties. This study aimed to investigate the critical long-term properties of oil-infused medical polyethylene after 4 weeks of accelerated thermal ageing. Samples treated with an oil (Vitamin E or Lipiodol) had a higher oxidation stability than currently used medical grade polyethylene, indicated by a smaller increase in oxidation index after ageing (Vitamin E + 36%, Lipiodol +40%, Untreated +136%, Thermally treated +164%). The tensile properties of oil treated polyethylene after ageing were significantly higher than the Untreated and Thermally treated controls (p<0.05) indicating less mechanical degradation. There was also no alteration in the percentage crystallinity of oil treated samples after ageing, though the radiopacity of the Lipiodol treated samples reduced by 54% after ageing. The leaching of oil with time was also investigated; the leaching of Lipiodol and Vitamin E followed the same trend and reached a steady state by two weeks. Overall, it can be concluded that the diffusion of an oil-based fluid into polyethylene not only increases the oxidative and chemical stability of polyethylene but also adds additional functionality (e.g. radiopacity) providing a more suitable material for long–term medical applications.

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Hypocalcemic cardiomyopathy after parathyroidectomy in a patient with uremia: A case report and literature review

Journal of International Medical Research ◽

10.1177/0300060520942115 ◽

2020 ◽

Vol 48 (7) ◽

pp. 030006052094211

Author(s):

Wei Zhang ◽

Feng Xue ◽

Quandong Bu ◽

Xuemei Liu

Keyword(s):

Heart Failure ◽

Case Report ◽

Secondary Hyperparathyroidism ◽

Calcium Supplementation ◽

Severe Heart Failure ◽

Cardiac Complications ◽

Refractory Heart Failure ◽

First Case ◽

Insight Into

Hypocalcemia is a rare, but reversible, cause of dilated cardiomyopathy. Although cardiomyopathy may cause severe heart failure, calcium supplementation can reverse heart failure. We report here a patient with uremia and secondary hyperparathyroidism, who was complicated by persistent hypocalcemia and refractory heart failure. The cardiac failure was refractory to treatment with digitalis and diuretics, but dramatically responded to calcium therapy and restoration of normocalcemia. As a result, the patient was eventually diagnosed with hypocalcemic cardiomyopathy. To the best of our knowledge, this is the first case of this disease to be reported in a patient with uremia. Findings from our case may help clinicians to better understand hypocalcemic cardiomyopathy. Our case might also provide new insight into long-term cardiac complications and prognoses of patients undergoing parathyroidectomy due to secondary hyperparathyroidism.

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R Coronae Borealis Stars: Long-Term Photometric & Spectroscopic Studies

Highlights of Astronomy ◽

10.1017/s1539299600021298 ◽

1998 ◽

Vol 11 (1) ◽

pp. 379-379

Author(s):

P.L. Cottrell ◽

L. Skuljan ◽

P.M. Kilmartin ◽

C. Gilmore ◽

W.A. Lawson

Keyword(s):

Radial Velocity ◽

Spectroscopic Studies ◽

Photometric Data ◽

Decline Phase ◽

Dust Clouds ◽

Medium Resolution ◽

Formation And Evolution ◽

R Coronae Borealis Stars ◽

Insight Into

For more than a decade we have been able to acquire and analyse a significant amount of photometric data of the highly variable R Coronae Borealis (RCB) stars. This has made been possible by a photometric service observing programme instigated at the Observatory. These photometric data have been combined with less extensive spectroscopic coverage, particularly of the decline phase of these stars. These have been supplemented by observations obtained at Mount Stromlo and Siding Spring Observatories for a radial velocity study. Significantly more spectroscopic observations are now being acquired with the development of a new medium resolution spectrograph at Mount John University Observatory. In this poster we will present recent photometric and spectroscopic results for a number of the RCB stars in our sample. This observational and analysis work can be used to provide further insight into the nature of these stars, their likely progeny and progenitors and the processes that are involved in the formation and evolution of the obscuring dust clouds which cause the decline phase.

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Characteristics of Liparis loeselii (L.) Rich. populations in selected Natura 2000 areas in eastern Poland

Folia Geobotanica ◽

10.1007/s12224-020-09371-7 ◽

2020 ◽

Vol 55 (3) ◽

pp. 151-162

Author(s):

Danuta Urban ◽

Joanna Sender ◽

Ewelina Tokarz ◽

Andrzej Różycki

Keyword(s):

Natura 2000 ◽

Total Carbon ◽

Habitat Conditions ◽

Total Carbon Content ◽

Poor Fen ◽

Calcareous Fen ◽

Liparis Loeselii ◽

The Individual ◽

Insight Into

AbstractIn view of the sensitivity of Liparis loeselii to changes in habitat conditions, we carried out a study with the aim to monitor population numbers, identify the individual features of the Liparis loeselii population, analyse habitat conditions, identify threats and propose conservation measures to preserve the species. The investigations were conducted in seven unmanaged objects located in three Natura 2000 areas in eastern Poland. The results of this study provide a new insight into Liparis loeselii ecology. The analysed populations inhabited some habitat types: extremely poor fen, transitional mire, rich fen, calcareous fen, spring-fed fen. The content of nutrients was similar in all the habitats. A CCA analysis revealed that the total carbon content, pH, and redox potential of the substrate determine differences between the habitats analysed. Juvenile individuals represented a maximum of 12% of the analysed populations and were the least abundant group of these plants. The flowering was primarily influenced by hydrological conditions. Based on the long-term observations reported in this article, it can be assumed that the species stands a chance of surviving at the localities analysed, provided that the habitat conditions do not change dramatically.

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