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

2020 ◽  
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.

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

PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0229703
Author(s):  
Helen D. Berry ◽  
Thomas F. Mumford ◽  
Bart Christiaen ◽  
Pete Dowty ◽  
Max Calloway ◽  
...  
Keyword(s):  
Puget Sound ◽  
Environmental Stressors ◽  
Nutrient Concentrations ◽  
Kelp Forests ◽  
High Current ◽  
Salish Sea ◽  
Climate Conditions ◽  
Kelp Beds ◽  
Biogenic Habitat

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 segments along 452 km of shoreline. Compared to the earliest baseline in 1878, Nereocystis extent in 2017 decreased 63%, with individual sub-basins showing up to 96% loss. Losses have persisted for decades, across a range of climate conditions. In recent decades, Nereocystis predominantly occurred along shorelines with intense currents and mixing, where temperature and nutrient concentrations did not reach thresholds for impacts to Nereocystis performance, and high current speeds likely excluded grazers. Losses predominated in areas with elevated temperature, lower nutrient concentrations, and relatively low current velocities. The pattern of long-term losses in SPS contrasts with stability in floating kelp abundance during the last century in an area of the Salish Sea with greater wave exposure and proximity to oceanic conditions. These findings support the hypothesis that kelp beds along wave-sheltered shorelines exhibit greater sensitivity to environmental stressors. Additionally, shorelines with strong currents and deep-water mixing may provide refugia within sheltered systems.

scholarly journals Production of mobile invertebrate communities on shallow reefs from temperate to tropical seas

2020 ◽  
Vol 287 (1941) ◽  
pp. 20201798
Author(s):  
K. M. Fraser ◽  
J. S. Lefcheck ◽  
S. D. Ling ◽  
C. Mellin ◽  
R. D. Stuart-Smith ◽  
...  
Keyword(s):  
Primary Productivity ◽  
Human Impacts ◽  
Anthropogenic Impacts ◽  
Selection Procedure ◽  
Marine Ecosystems ◽  
Environmental Drivers ◽  
Kelp Forests ◽  
Food Web Structure ◽  
Continental Scale ◽  
Biogenic Habitat

Primary productivity of marine ecosystems is largely driven by broad gradients in environmental and ecological properties. By contrast, secondary productivity tends to be more variable, influenced by bottom-up (resource-driven) and top-down (predatory) processes, other environmental drivers, and mediation by the physical structure of habitats. Here, we use a continental-scale dataset on small mobile invertebrates (epifauna), common on surfaces in all marine ecosystems, to test influences of potential drivers of temperature-standardized secondary production across a large biogeographic range. We found epifaunal production to be remarkably consistent along a temperate to tropical Australian latitudinal gradient of 28.6°, spanning kelp forests to coral reefs (approx. 3500 km). Using a model selection procedure, epifaunal production was primarily related to biogenic habitat group, which explained up to 45% of total variability. Production was otherwise invariant to predictors capturing primary productivity, the local biomass of fishes (proxy for predation pressure), and environmental, geographical, and human impacts. Highly predictable levels of epifaunal productivity associated with distinct habitat groups across continental scales should allow accurate modelling of the contributions of these ubiquitous invertebrates to coastal food webs, thus improving understanding of likely changes to food web structure with ocean warming and other anthropogenic impacts on marine ecosystems.

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

The Holocene ◽  
2019 ◽  
Vol 29 (8) ◽  
pp. 1335-1349 ◽  
Author(s):  
Małgorzata Latałowa ◽  
Joanna Święta-Musznicka ◽  
Michał Słowiński ◽  
Anna Pędziszewska ◽  
Agnieszka M Noryśkiewicz ◽  
...  
Keyword(s):  
Human Impacts ◽  
Population Decline ◽  
Alnus Glutinosa ◽  
Similar Process ◽  
Ecological Disturbance ◽  
Pollen Diagrams ◽  
First Millennium ◽  
Floods And Droughts ◽  
Insight Into

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.

scholarly journals LSD-25 as an Adjunct to Long-Term Psychotherapy

1966 ◽  
Vol 11 (4) ◽  
pp. 330-342 ◽  
Author(s):  
Robert Pos
Keyword(s):  
Total Duration ◽  
Therapeutic Benefit ◽  
Treatment Procedure ◽  
Treatment Variable ◽  
Experimental Subjects ◽  
Almost All ◽  
Insight Into ◽  
All Treatment

The author describes his experience with LSD-25 as an adjunct to long-term psychotherapy in 24 patients between September, 1962 and May, 1965, involving a total of 56 LSD-25 sessions for a total duration of 119 1/4 hours. Where therapy blocks developed which could not be overcome, narcoanalysis with or without methylphenidate† was used and if this was not successful LSD-25 was considered. The 24 experimental subjects were almost all suffering from disabling and long-standing psychiatric difficulties. In five out of 24 patients LSD-25 did seem to help the patient to overcome therapeutic blocks successfully; five patients showed only temporary movement and relapsed; 12 patients showed no therapeutic movement whatsoever; in two patients the follow-up was insufficient. There was no stable correlation between the extent of the psychedelic experience and the amount of therapeutic benefit. The events of the LSD-25 sessions could not be predicted on the basis of pre-LSD-25 experience with the patient, nor could the therapeutic outcome of the LSD-25 sessions be predicted on the basis of the session itself, or even on the basis of the first days or weeks following the session. LSD-25 appeared as a sometimes helpful though usually unpredictable treatment variable within the over-all treatment program. When introduced as an adjunct late in the treatment procedure it did not seem to have any untoward psychodynamic effects and no undue increase in suicidal tendencies was noted. The therapist's insight into the patient's dynamics was always increased, though this could far from always be translated into therapeutic benefit.

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

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”.

Is 3 years adequate for tracking completely occluded coiled aneurysms?

2020 ◽  
Vol 133 (3) ◽  
pp. 758-764
Author(s):  
Eung Koo Yeon ◽  
Young Dae Cho ◽  
Dong Hyun Yoo ◽  
Su Hwan Lee ◽  
Hyun-Seung Kang ◽  
...  
Keyword(s):  
De Novo ◽  
Careful Monitoring ◽  
Surveillance Period ◽  
Radiological Data ◽  
De Novo Aneurysm ◽  
Low Probability ◽  
Almost All ◽  
Annual Risk

OBJECTIVEThe authors conducted a study to ascertain the long-term durability of coiled aneurysms completely occluded at 36 months’ follow-up given the potential for delayed recanalization.METHODSIn this retrospective review, the authors examined 299 patients with 339 aneurysms, all shown to be completely occluded at 36 months on follow-up images obtained between 2011 and 2013. Medical records and radiological data acquired during the extended monitoring period (mean 74.3 ± 22.5 months) were retrieved, and the authors analyzed the incidence of (including mean annual risk) and risk factors for delayed recanalization.RESULTSA total of 5 coiled aneurysms (1.5%) occluded completely at 36 months showed recanalization (0.46% per aneurysm-year) during the long-term surveillance period (1081.9 aneurysm-years), 2 surfacing within 60 months and 3 developing thereafter. Four showed minor recanalization, with only one instance of major recanalization. The latter involved the posterior communicating artery as an apparent de novo lesion, arising at the neck of a firmly coiled sac, and was unrelated to coil compaction or growth. Additional embolization was undertaken. In a multivariate analysis, a second embolization for a recurrent aneurysm (HR = 22.088, p = 0.003) independently correlated with delayed recanalization.CONCLUSIONSAlmost all coiled aneurysms (98.5%) showing complete occlusion at 36 months postembolization proved to be stable during extended observation. However, recurrent aneurysms were predisposed to delayed recanalization. Given the low probability yet seriousness of delayed recanalization and the possibility of de novo aneurysm formation, careful monitoring may be still considered in this setting but at less frequent intervals beyond 36 months.

Moving Songs

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.

The geography of climate migration

2021 ◽  
pp. 1-37
Author(s):  
Michał Burzyński ◽  
Frédéric Docquier ◽  
Hendrik Scheewel
Keyword(s):  
Climate Change ◽  
International Migration ◽  
First Century ◽  
Long Term Effects ◽  
Mobility Data ◽  
Rural And Urban ◽  
Working Age ◽  
Internal Mobility ◽  
Almost All

Abstract In this paper, we investigate the long-term effects of climate change on the mobility of working-age people. We use a world economy model that covers almost all the countries around the world, and distinguishes between rural and urban regions as well as between flooded and unflooded areas. The model is calibrated to match international and internal mobility data by education level for the last 30 years, and is then simulated under climate change variants. We endogenize the size, dyadic, and skill structure of climate migration. When considering moderate climate scenarios, we predict mobility responses in the range of 70–108 million workers over the course of the twenty-first century. Most of these movements are local or inter-regional. South–South international migration responses are smaller, while the South–North migration response is of the “brain drain” type and induces a permanent increase in the number of foreigners in OECD countries in the range of 6–9% only. Changes in the sea level mainly translate into forced local movements. By contrast, inter-regional and international movements are sensitive to temperature-related changes in productivity. Lastly, we show that relaxing international migration restrictions may exacerbate the poverty effect of climate change at origin if policymakers are unable to select/screen individuals in extreme poverty.

scholarly journals The Demerger Impact upon Sustainable Development of Economic Entities: Evidence from Romania

2021 ◽  
Vol 13 (15) ◽  
pp. 8316
Author(s):  
Camelia Mirela Baba ◽  
Constantin Duguleană ◽  
Marius Sorin Dincă ◽  
Liliana Duguleană ◽  
Gheorghița Dincă
Keyword(s):  
Sustainable Development ◽  
Business Strategies ◽  
The Sustainable Development ◽  
Ex Post ◽  
Before And After ◽  
Almost All ◽  
The Impact ◽  
Profitability Ratios ◽  
Positive Effect

The Covid-19 induced economic crisis has significantly affected almost all businesses from nearly every sector, causing severe financial problems, lack of cash assets, and decrease of revenues. In this context, the economic entities were forced to look for adjustment and rescue solutions of their activities. One possible solution for the recovery and reorganization of economic entities’ activities is demerger. This paper evaluates the impact of demerger upon the sustainable development of economic entities in terms of economic efficiency and financial performances. To achieve this goal, a statistical analysis of profitability ratios before and after the demerger, as well as a structural analysis of 268 demerger projects for the April 2012–April 2021 period, were performed. The results attest there are no significant differences between the ex-ante and ex-post financial performances. However, demerger seems to have a positive effect upon analyzed companies helping them to overcome economic hardships, rethink their business strategies, and continue their activity in the medium and long-term time horizon.

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