| 1. |
- Arft, M, et al.
(författare)
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Responses of tundra plants to experimental warming : Meta-analysis of the international tundra experiment
- 1999
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Ingår i: Ecological Monographs. - 0012-9615 .- 1557-7015. ; 69:4, s. 491-511
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Tidskriftsartikel (refereegranskat)abstract
- The International Tundra Experiment (ITEX) is a collaborative, multisite experiment using a common temperature manipulation to examine variability in species response across climatic and geographic gradients of tundra ecosystems. ITEX was designed specifically to examine variability in arctic and alpine species response to increased temperature. We compiled from one to four years of experimental data from 13 different ITEX sites and used meta-analysis to analyze responses of plant phenology, growth, and reproduction to experimental warming. Results indicate that key phenological events such as leaf bud burst and flowering occurred earlier in warmed plots throughout the study period; however, there was little impact on growth cessation at the end of the season. Quantitative measures of vegetative growth were greatest in warmed plots in the early years of the experiment, whereas reproductive effort and success increased in later years. A shift away from vegetative growth and toward reproductive effort and success in the fourth treatment year suggests a shift from the initial response to a secondary response. The change in vegetative response may be due to depletion of stored plant reserves, whereas the lag in reproductive response may be due to the formation of flower buds one to several seasons prior to flowering. Both vegetative and reproductive responses varied among life-forms; herbaceous forms had stronger and more consistent vegetative growth responses than did woody forms. The greater responsiveness of the herbaceous forms may be attributed to their more flexible morphology and to their relatively greater proportion of stored plant reserves. Finally, warmer, low arctic sites produced the strongest growth responses, but colder sites produced a greater reproductive response. Greater resource investment in vegetative growth may be a conservative strategy in the Low Arctic, where there is more competition for light, nutrients, or water, and there may be little opportunity for successful germination or seedling development. In contrast, in the High Arctic, heavy investment in producing seed under a higher temperature scenario may provide an opportunity for species to colonize patches of unvegetated ground. The observed differential response to warming suggests that the primary forces driving the response vary across climatic zones, functional groups, and through time.
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| 2. |
- Cornelissen, Johannes H C, et al.
(författare)
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Global negative vegetation feedback to climate warming responses of leaf litter decomposition rates in cold biomes
- 2007
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Ingår i: Ecology Letters. - : Wiley. - 1461-023X .- 1461-0248. ; 10:7, s. 619-627
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Tidskriftsartikel (refereegranskat)abstract
- Whether climate change will turn cold biomes from large long-term carbon sinks into sources is hotly debated because of the great potential for ecosystem-mediated feedbacks to global climate. Critical are the direction, magnitude and generality of climate responses of plant litter decomposition. Here, we present the first quantitative analysis of the major climate-change-related drivers of litter decomposition rates in cold northern biomes worldwide.Leaf litters collected from the predominant species in 33 global change manipulation experiments in circum-arctic-alpine ecosystems were incubated simultaneously in two contrasting arctic life zones. We demonstrate that longer-term, large-scale changes to leaf litter decomposition will be driven primarily by both direct warming effects and concomitant shifts in plant growth form composition, with a much smaller role for changes in litter quality within species. Specifically, the ongoing warming-induced expansion of shrubs with recalcitrant leaf litter across cold biomes would constitute a negative feedback to global warming. Depending on the strength of other (previously reported) positive feedbacks of shrub expansion on soil carbon turnover, this may partly counteract direct warming enhancement of litter decomposition.
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| 3. |
- Dean, E., et al.
(författare)
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Health Competency Standards in Physical Therapist Practice
- 2019
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Ingår i: Physical Therapy. - : NLM (Medline). - 0031-9023 .- 1538-6724. ; 99:9, s. 1242-1254
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Tidskriftsartikel (refereegranskat)abstract
- Although the physical therapist profession is the leading established, largely nonpharmacological health profession in the world and is committed to health promotion and noncommunicable disease (NCD) prevention, these have yet to be designated as core physical therapist competencies. Based on findings of 3 Physical Therapy Summits on Global Health, addressing NCDs (heart disease, cancer, hypertension, stroke, diabetes, obesity, and chronic lung disease) has been declared an urgent professional priority. The Third Summit established the status of health competencies in physical therapist practice across the 5 World Confederation for Physical Therapy (WCPT) regions with a view to establish health competency standards, this article's focus. Three general principles related to health-focused practice emerged, along with 3 recommendations for its inclusion. Participants acknowledged that specific competencies are needed to ensure that health promotion and NCD prevention are practiced consistently by physical therapists within and across WCPT regions (ie, effective counseling for smoking cessation, basic nutrition, weight control, and reduced sitting and increased activity/exercise in patients and clients, irrespective of their presenting complaints/diagnoses). Minimum accreditable health competency standards within the profession, including use of the WCPT-supported Health Improvement Card, were recommended for inclusion into practice, entry-to-practice education, and research. Such standards are highly consistent with the mission of the WCPT and the World Health Organization. The physical therapist profession needs to assume a leadership role vis-à-vis eliminating the gap between what we know unequivocally about the causes of and contributors to NCDs and the long-term benefits of effective, sustained, nonpharmacological lifestyle behavior change, which no drug nor many surgical procedures have been reported to match.
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| 4. |
- Cornelissen, C, et al.
(författare)
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Global change and arctic ecosystems : is lichen decline a function of increases in vascular plant biomass?
- 2001
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Ingår i: Journal of Ecology. - : Wiley. - 0022-0477 .- 1365-2745. ; 89:6, s. 984-994
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Tidskriftsartikel (refereegranskat)abstract
- 1 Macrolichens are important for the functioning and biodiversity of cold northern ecosystems and their reindeer-based cultures and economics. 2 We hypothesized that, in climatically milder parts of the Arctic, where ecosystems have relatively dense plant canopies, climate warming and/or increased nutrient availability leads to decline in macrolichen abundance as a function of increased abundance of vascular plants. In more open high-arctic or arctic-alpine plant communities such a relationship should be absent. To test this, we synthesized cross-continental arctic vegetation data from ecosystem manipulation experiments simulating mostly warming and increased nutrient availability, and compared these with similar data from natural environmental gradients. 3 Regressions between abundance or biomass of macrolichens and vascular plants were consistently negative across the subarctic and mid-arctic experimental studies. Such a pattern did not emerge in the coldest high-arctic or arctic-alpine sites. The slopes of the negative regressions increased across 10 sites as the climate became milder (as indicated by a simple climatic index) or the vegetation denser (greater site above-ground biomass). 4 Seven natural vegetation gradients in the lower-altitude sub- and mid-arctic zone confirmed the patterns seen in the experimental studies, showing consistent negative relationships between abundance of macrolichens and vascular plants. 5 We conclude that the data supported the hypothesis. Macrolichens in climatically milder arctic ecosystems may decline if and where global changes cause vascular plants to increase in abundance. 6 However, a refining of our findings is needed, for instance by integrating other abiotic and biotic effects such as reindeer grazing feedback on the balance between vascular plants and lichens.
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| 5. |
- Dean, Elizabeth, et al.
(författare)
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Immuno-modulation with lifestyle behaviour change to reduce SARS-CoV-2 susceptibility and COVID-19 severity : goals consistent with contemporary physiotherapy practice
- 2022
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Ingår i: Physiotherapy. - : ELSEVIER SCI LTD. - 0031-9406 .- 1873-1465. ; 114, s. 63-67
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Tidskriftsartikel (refereegranskat)abstract
- Lifestyle-related non-communicable diseases (NCDs) and their risk factors are unequivocally associated with SARS-CoV-2 susceptibility and COVID-19 severity. NCD manifestations and their lifestyle risks are associated with chronic low-grade systemic inflammation (CLGSI). This review supports that immuno-modulation with positive lifestyle change aimed at reducing SARS-CoV-2 susceptibility and COVID-19 severity, is a goal consistent with contemporary physiotherapy practice. Physiotherapists have a long tradition of managing a , thus, managing CLGSI is a logical extension. Improving patients' lifestyle practices also reduces their NCD risks and increases activity/exercise capacity, health and wellbeing - all principal goals of contemporary physiotherapy. The COVID-19 pandemic lends further support for prioritising health and lifestyle competencies including smoking cessation; whole food plant-based nutrition; healthy weight; healthy sleep practices; and stress management; in conjunction with reducing sedentariness and increasing physical activity/exercise, to augment immunity as well as function and overall health and wellbeing. To support patients' lifestyle change efforts, physiotherapists may refer patients to other health professionals. The authors conclude that immuno-modulation with lifestyle behaviour change to reduce susceptibility to viruses including SARS-CoV-2, is consistent with contemporary physiotherapy practice. Immuno-modulation needs to be reflected in health competencies taught in physiotherapy professional education curricula and taught at standards comparable to other established interventions.(c) 2021 The Author(s).
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