scholarly journals Long-Term Forest Dynamics of Oromediterranean Fir Forests in Greece

2020 ◽  
Vol 11 (1) ◽  
pp. 71-84
Author(s):  
Robert Brandes ◽  
Anastasia Christopoulou

The present study illustrates the situation of the genus Abies in the Mediterranean and in Greece, focusing in detail on the oromediterranean forest of the southern Peloponnese, at Mt. Taygetos. The existing pattern of forest dynamics (mosaic cycle) and also the timberline dynamics are presented and explained. Since fir forests are highly susceptible to drought-related impacts (fire and fir dieback: insect outbreaks/ forest pathogens), the analysis of the present situation is put into perspective by looking at the role of direct human influence and the climatic fluctuations of the past, taking into consideration dendrochronological findings and archival climate records. In view of climate warming the question is whether in recent decades the fingerprints of climate change can already be observed in the Greek fir forests. The study concludes that drought periods and climatic extremes have been an essential part of Greek climate for many centuries, causing high natural forest vulnerability. Therefore, fir dieback and fires are not a new phenomenon either – but in recent decades the accumulation of fuel, caused by land abandonment, has increased the danger of large wildfires. Nevertheless, the Greek mountain forests are highly endangered by increases in aridity and/or more frequent climate extremes (heat waves), together with increased risk of wildfires. Recommendations for an active forest management (counteracting expected adverse effects of climate change, by focusing on the establishment of an Abies cephalonica Loudon /Pinus nigra J. F. Arnold mosaic cycle) and further scientific research are provided.

Author(s):  
James ROSE

ABSTRACT Within the context of the work and achievements of James Croll, this paper reviews the records of direct observations of glacial landforms and sediments made by Charles Lyell, Archibald and James Geikie and James Croll himself, in order to evaluate their contributions to the sciences of glacial geology and Quaternary environmental change. The paper outlines the social and physical environment of Croll's youth and contrasts this with the status and experiences of Lyell and the Geikies. It also outlines the character and role of the ‘Glasgow School’ of geologists, who stimulated Croll's interest into the causes of climate change and directed his focus to the glacial and ‘interglacial’ deposits of central Scotland. Contributions are outlined in chronological order, drawing attention to: (i) Lyell's high-quality observations and interpretations of glacial features in Glen Clova and Strathmore and his subsequent rejection of the glacial theory in favour of processes attributed to floating icebergs; (ii) the significant impact of Archibald Geikie's 1863 paper on the ‘glacial drift of Scotland’, which firmly established the land-ice theory; (iii) the fact that, despite James Croll's inherent dislike of geology and fieldwork, he provided high-quality descriptions and interpretations of the landforms and sediments of central Scotland in order to test his theory of climate change; and (iv) the great communication skills of James Geikie, enhanced by contacts and evidence from around the world. It is concluded that whilst direct observations of glacial landforms and sediments were critical to the long-term development of the study of glaciation, the acceptance of this theory was dependent also upon the skills, personality and status of the Geikies and Croll, who developed and promoted the concepts. Sadly, the subsequent rejection of the land-ice concept by Lyell resulted in the same factors challenging the acceptance of the glacial theory.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
T Kawai ◽  
D Nakatani ◽  
T Yamada ◽  
T Watanabe ◽  
T Morita ◽  
...  

Abstract Background Diuretics has been reported to have a potential for an activation of the renin-angiotensin-aldosterone system and the sympathetic nervous system, leading to a possibility of poor clinical outcome in patients with cardiovascular disease. However, few data are available on clinical impact of diuretics on long-term outcome in patients with acute myocardial infarction (AMI) based on plasma volume status. Methods To address the issue, a total of 3,416 survived patients with AMI who were registered to a large database of the Osaka Acute Coronary Insufficiency Study (OACIS) were studied. Plasma volume status was assessed with the estimated plasma volume status (ePVS) that was calculated at discharge as follows: actual PV = (1 − hematocrit) × [a + (b × body weight)] (a=1530 in males and a=864 in females, b=41.0 in males and b=47.9 in females); ideal PV = c × body weight (c=39 in males and c=40 in females), and ePVS = [(actual PV − ideal PV)/ideal PV] × 100 (%). Multivariable Cox regression analysis and propensity score matching were performed to account for imbalances in covariates. The endpoint was all-cause of death (ACD) within 5 years. Results During a median follow-up period of 855±656 days, 193 patients had ACD. In whole population, there was no significant difference in long-term mortality risk between patients with and without diuretics in both multivariate cox regression model and propensity score matching population. When patients were divided into 2 groups according to ePVS with a median value of 4.2%, 46 and 147 patients had ACD in groups with low ePVS and high ePVS, respectively. Multivariate Cox analysis showed that use of diuretics was independently associated with an increased risk of ACD in low ePVS group, (HR: 2.63, 95% confidence interval [CI]: 1.22–5.63, p=0.01), but not in high ePVS group (HR: 0.70, 95% CI: 0.44–1.10, p=0.12). These observations were consistent in the propensity-score matched cohorts; the 5-year mortality rate was significantly higher in patients with diuretics than those without among low ePVS group (4.7% vs 1.7%, p=0.041), but not among high ePVS group (8.0% vs 10.3%, p=0.247). Conclusion Prescription of diuretics at discharge was associated with increased risk of 5-year mortality in patients with AMI without PV expansion, but not with PV expansion. The role of diuretics on long-term mortality may differ in plasma volume status. Therefore, prescription of diuretics after AMI may be considered based on plasma volume status. Funding Acknowledgement Type of funding source: None


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Francesco Santoro ◽  
Tecla Zimotti ◽  
Adriana Mallardi ◽  
Alessandra Leopizzi ◽  
Enrica Vitale ◽  
...  

AbstractTakotsubo syndrome (TTS) is an acute heart failure syndrome with significant rates of in and out-of-hospital mayor cardiac adverse events (MACE). To evaluate the possible role of neoplastic biomarkers [CA-15.3, CA-19.9 and Carcinoembryonic Antigen (CEA)] as prognostic marker at short- and long-term follow-up in subjects with TTS. Ninety consecutive subjects with TTS were enrolled and followed for a median of 3 years. Circulating levels of CA-15.3, CA-19.9 and CEA were evaluated at admission, after 72 h and at discharge. Incidence of MACE during hospitalization and follow-up were recorded. Forty-three (46%) patients experienced MACE during hospitalization. These patients had increased admission levels of CEA (4.3 ± 6.2 vs. 2.2 ± 1.5 ng/mL, p = 0.03). CEA levels were higher in subjects with in-hospital MACE. At long term follow-up, CEA and CA-19.9 levels were associated with increased risk of death (log rank p < 0.01, HR = 5.3, 95% CI 1.9–14.8, HR = 7.8 95% CI 2.4–25.1, respectively, p < 0.01). At multivariable analysis levels higher than median of CEA, CA-19.9 or both were independent predictors of death at long term (Log-Rank p < 0.01). Having both CEA and CA-19.9 levels above median (> 2 ng/mL, > 8 UI/mL respectively) was associated with an increased risk of mortality of 11.8 (95% CI 2.6–52.5, p = 0.001) at follow up. Increased CEA and CA-19.9 serum levels are associated with higher risk of death at long-term follow up in patients with TTS. CEA serum levels are correlated with in-hospital MACE.


Author(s):  
Jiban Mani Poudel

In the 21st century, global climate change has become a public and political discourse. However, there is still a wide gap between global and local perspectives. The global perspective focuses on climate fluctuations that affect the larger region; and their analysis is based on long-term records over centuries and millennium. By comparison, local peoples’ perspectives vary locally, and local analyses are limited to a few days, years, decades and generations only. This paper examines how farmers in Kirtipur of Kathmandu Valley, Nepal, understand climate variability in their surroundings. The researcher has used a cognized model to understand farmers’ perception on weather fluctuations and climate change. The researcher has documented several eyewitness accounts of farmers about weather fluctuations which they have been observing in a lifetime. The researcher has also used rainfall data from 1970-2009 to test the accuracy of perceptions. Unlike meteorological analyses, farmers recall and their understanding of climatic variability by weather-crop interaction, and events associating with climatic fluctuations and perceptions are shaped by both physical visibility and cultural frame or belief system.DOI: http://dx.doi.org/10.3126/hn.v11i1.7200 Hydro Nepal Special Issue: Conference Proceedings 2012 pp.30-34


Author(s):  
Andrew E. McKechnie

The direct impacts of higher temperatures on birds are manifested over timescales ranging from minutes and hours to years and decades. Over short timescales, acute exposure to high temperatures can lead to hyperthermia or dehydration, which among arid-zone species occasionally causes catastrophic mortality events. Over intermediate timescales of days to weeks, high temperatures can have chronic sub-lethal effects via body mass loss or reduced nestling growth rates, negatively affecting sev eral fitness components. Long-term effects of warming manifested over years to decades involve declining body mass or changes in appendage size. Key directions for future research include elucidating the role of phenotypic plasticity and epigenetic processes in avian adaptation to climate change, examining the role of stress pathways in mediating responses to heat events, and understanding the consequences of higher temperatures for species that traverse hot regions while migrating.


2019 ◽  
Vol 29 (Supplement_4) ◽  
Author(s):  
C Macdougall ◽  
L Gibbs

Abstract Background In February 2009 Victorian rural communities were hit by the worst bushfires in Australian history. Immediately we evaluated community groups preparing residents for bushfires. Ten years on, we are one of the few teams to evaluate medium to long term community recovery using multiple methods. As climate change becomes more visible, the frequency and intensity of disasters will increase so communities, governments and service providers need more evidence based strategies and policies. We explore how participant led visual methods provide new knowledge. Methods In study 1 participants in 3 of 7 focus groups in peoples’ homes spontaneously brought photos for us to examine before the discussions. In another participants spoke of the importance of photos they took at the time. We returned to the field to interview people in their homes about the meaning and role of photos. Results Participants wanted to inform us-as outsiders-of the awe and enormity of the fires. They created a visual record to communicate with key interest groups and ward off complacity as memories receded. Photos helped them construct timelines and meanings of the intense fires. Crucially, they recorded recovery and rebuilding in both the built and natural environments. Over the next ten years we chronicled stories from community led visual methods of communication, recovery and empowerment. We incorporated into qualitative methods participant led tours of their environments, with visual methods. Visual data collected by communities focused more strongly on the natural environment than researcher led verbal methods. Conclusions Visual sociology changes as technology provides participants in research with increased access to, and control over, visual methods. These changes can rebalance power relations between qualitative researchers and participants and bridge visual and verbal methods; crafting striking stories to influence those Australian policies unresponsive to climate change. Key messages Technological change enables participants in qualitative research to initiate visual methods to build bridges between them and researchers. Community led visual methods provide new types of data useful for theory and knowledge translation.


2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Stephanie E. Hallows ◽  
Timothy R. H. Regnault ◽  
Dean H. Betts

Placental insufficiency, maternal malnutrition, and other causes of intrauterine growth restriction (IUGR) can significantly affect short-term growth and long-term health. Following IUGR, there is an increased risk for cardiovascular disease and Type 2 Diabetes. The etiology of these diseases is beginning to be elucidated, and premature aging or cellular senescence through increased oxidative stress and DNA damage to telomeric ends may be initiators of these disease processes. This paper will explore the areas where telomere and telomerase biology can have significant effects on various tissues in the body in IUGR outcomes.


2020 ◽  
Author(s):  
Marc Jaxa-Rozen ◽  
Evelina Trutnevyte

&lt;p&gt;Solar photovoltaic (PV) technology has been the fastest-growing renewable energy technology in recent years. Since 2009, it has in fact experienced the largest capacity growth of any power generation technology, with benchmark levelized costs falling by four-fifths [1]. In addition, the global technical potential of PV largely exceeds global primary energy demand [2]. Nonetheless, PV typically only appears as a relatively marginal option in long-term energy modelling studies and scenarios. These include the mitigation pathways evaluated in the context of the work of the Intergovernmental Panel on Climate Change (IPCC), which rely on integrated assessment models (IAMs) of climate change and have in the past underestimated PV growth as compared to observed rates of adoption [2]. Similarly, global energy projections, such as the International Energy Agency's World Energy Outlook, have been relatively conservative regarding the role of solar PV in long-term energy transitions.&lt;/p&gt;&lt;p&gt;In order to better understand the long-term global role of solar PV as perceived by various modeling communities, this work synthesizes a broad ensemble of scenarios for global PV adoption at the 2050 horizon. This ensemble includes 784 IAM-based scenarios from the IPCC SR15 and AR5 databases, and 82 other systematically selected scenarios published over the 2010-2019 period in the academic and gray literature, such as PV-focused techno-economic analyses and global energy outlooks. The scenarios are analyzed using a descriptive framework which combines scenario indicators (e.g. mitigation policies depicted in a scenario), model indicators (e.g. the representation of technological change in the underlying model), and meta-indicators (e.g. the type of institution which authored a scenario). We extend this scenario framework to include a text-mining approach, using Latent Dirichlet Allocation (LDA) to associate scenarios with different textual perspectives identified in the ensemble, such as energy access or renewable energy transitions. We then use a scenario discovery approach to identify the combinations of indicators which are most strongly associated with different regions of the scenario space.&lt;/p&gt;&lt;p&gt;Preliminary results indicate that the date of publication of a scenario has a predominant influence on projected PV adoption values: scenarios published in the first half of the 2010s thus tend to represent considerably lower PV adoption levels. In parallel, higher projected values are more strongly associated with renewable-focused institutions. Increasing the institutional diversity of scenario ensembles may thus lead to a broader range of considered futures [3].&lt;/p&gt;&lt;p&gt;&amp;#8195;&lt;br&gt;References&lt;br&gt;[1] Frankfurt School-UNEP Centre, &amp;#8220;Global Trends in Renewable Energy Investment 2019,&amp;#8221; Frankfurt, Germany, 2019.&lt;br&gt;[2] F. Creutzig, P. Agoston, J. C. Goldschmidt, G. Luderer, G. Nemet, and R. C. Pietzcker, &amp;#8220;The underestimated potential of solar energy to mitigate climate change,&amp;#8221; Nat Energy, vol. 2, no. 9, pp. 1&amp;#8211;9, Aug. 2017, doi: 10.1038/nenergy.2017.140.&lt;br&gt;[3] E. Trutnevyte, W. McDowall, J. Tomei, and I. Keppo, &amp;#8220;Energy scenario choices: Insights from a retrospective review of UK energy futures,&amp;#8221; Renewable and Sustainable Energy Reviews, vol. 55, pp. 326&amp;#8211;337, Mar. 2016, doi: 10.1016/j.rser.2015.10.067.&lt;/p&gt;


Author(s):  
M. J. Kelly

Just under half of all energy consumption in the UK today takes place indoors, and over a quarter within our homes. The challenges associated with energy security, climate change and sustainable consumption will be overcome or lost in our existing buildings. A background analysis, and the scale of the engineering challenge for the next three to four decades, is described in this paper.


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