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This study aims to assess in situ the impact of effluents originating from an Atlantic salmon (Salmo salar) farm on a nearby slender sea pen (Virgularia mirabilis) field. We evidenced (1) the presence and persistence of emamectin residues (i.e. a common chemotherapeutants used for treating ectoparasites in salmons) in V. mirabilis tissue 56 days after treatment and (2) lethal and sublethal responses of V. mirabilis to effluents discharged by the salmon farm. Particularly, sea pens near the fish farm exhibited significant overproduction of mucus, contraction of polyps' tentacles, and disappearance of associated fauna. Furthermore, sea pens located directly underneath the farm showed substantial tissue necrosis and, in the most severe case, complete tissue loss and mortality. Our results suggest that lethal damages on sea pens occur directly below the farm, and that sublethal effects are visible up to 500 m from the farm. However, the presence of V. mirabilis below the studied farm, which has been active for more than twenty years, suggests that V. mirabilis population possesses the capacity to recover from the impacts of the farm, thereby preventing the complete disappearance from the area. In this context, it would be particularly interesting to run a temporal survey following the health state of V. mirabilis during an entire production cycle to have a more precise overview of fish farm impacts on this species, including during and after the post-production fallowing period.
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Aquicultura , Salmo salar , Animais , Salmo salar/parasitologia , Poluentes Químicos da Água/toxicidade , Ivermectina/análogos & derivados , Ivermectina/farmacologiaRESUMO
BACKGROUND: Hospitals worldwide have implemented Rapid Response Systems (RRS) to facilitate early recognition and prompt response by trained personnel to deteriorating patients. A key concept of this system is that it should prevent 'events of omission', including failure to monitor patients' vital signs, delayed detection, and treatment of deterioration and delayed transfer to an intensive care unit. Time matters when a patient deteriorates, and several in-hospital challenges may prevent the RRS from functioning adequately. Therefore, we must understand and address barriers for timely and adequate responses in cases of patient deterioration. Thus, this study aimed to investigate whether implementing (2012) and developing (2016) an RRS was associated with an overall temporal improvement and to identify needs for further improvement by studying; patient monitoring, omission event occurrences, documentation of limitation of medical treatment, unexpected death, and in-hospital- and 30-day mortality rates. METHODS: We performed an interprofessional mortality review to study the trajectory of the last hospital stay of patients dying in the study wards in three time periods (P1, P2, P3) from 2010 to 2019. We used non-parametric tests to test for differences between the periods. We also studied overall temporal trends in in-hospital- and 30-day mortality rates. RESULTS: Fewer patients experienced omission events (P1: 40%, P2: 20%, P3: 11%, P = 0.01). The number of documented complete vital sign sets, median (Q1,Q3) P1: 0 (0,0), P2: 2 (1,2), P3: 4 (3,5), P = 0.01) and intensive care consultations in the wards ( P1: 12%, P2: 30%, P3: 33%, P = 0.007) increased. Limitations of medical treatment were documented earlier (median days from admission were P1: 8, P2: 8, P3: 3, P = 0.01). In-hospital and 30-day mortality rates decreased during this decade (rate ratios 0.95 (95% CI: 0.92-0.98) and 0.97 (95% CI: 0.95-0.99)). CONCLUSION: The RRS implementation and development during the last decade was associated with reduced omission events, earlier documentation of limitation of medical treatments, and a temporal reduction in the in-hospital- and 30-day mortality rates in the study wards. The mortality review is a suitable method to evaluate an RRS and provide a foundation for further improvement. TRIAL REGISTRATION: Retrospectively registered.
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Procedimentos Cirúrgicos do Sistema Digestório , Humanos , Hospitalização , Tempo de Internação , Unidades de Terapia Intensiva , Cuidados Críticos , Mortalidade HospitalarRESUMO
Plant removal experiments allow assessment of the role of biotic interactions among species or functional groups in community assembly and ecosystem functioning. When replicated along climate gradients, they can assess changes in interactions among species or functional groups with climate. Across twelve sites in the Vestland Climate Grid (VCG) spanning 4 °C in growing season temperature and 2000 mm in mean annual precipitation across boreal and alpine regions of Western Norway, we conducted a fully factorial plant functional group removal experiment (graminoids, forbs, bryophytes). Over six years, we recorded biomass removed, soil microclimate, plant community composition and structure, seedling recruitment, ecosystem carbon fluxes, and reflectance in 384 experimental and control plots. The dataset consists of 5,412 biomass records, 360 species-level biomass records, 1,084,970 soil temperature records, 4,771 soil moisture records, 17,181 plant records covering 206 taxa, 16,656 seedling records, 3,696 ecosystem carbon flux measurements, and 1,244 reflectance measurements. The data can be combined with longer-term climate data and plant population, community, ecosystem, and functional trait data collected within the VCG.
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Ecossistema , Pradaria , Biodiversidade , Biomassa , Carbono , Mudança Climática , Plantas , Solo/químicaRESUMO
Climate change is altering the world's ecosystems through direct effects of climate warming and precipitation changes but also indirectly through changes in biotic interactions. For instance, climate-driven changes in plant and/or insect communities may alter plant-pollinator interactions, thereby influencing plant reproductive success and ultimately population dynamics of insect-pollinated plants. To better understand how the importance of insect pollination for plant fruit set varies with climate, we experimentally excluded pollinators from the partly selfing keystone species Vaccinium myrtillus along elevational gradients in the forest-tundra ecotone in central Norway. The study comprised three mountain areas, seven elevational gradients spanning from the climatically relatively benign birch forest to the colder alpine areas above the tree line, and 180 plots of 1 × 1 m, with experimental treatments allocated randomly to plots within sites. Within the experimental plots, we counted the number of flowers of V. myrtillus and counted and weighed all fruits, as well as seeds for a selection of fruits. Excluding pollinators resulted in lower fruit production, as well as reduced fruit and seed mass of V. myrtillus. In the alpine sites pollinator exclusion resulted in 84% fewer fruits, 50% lower fruit weight, and 50% lower seed weight compared to control conditions. Contrary to our expectations, the negative effect of pollinator exclusion was less pronounced in the forest compared to alpine sites, suggesting that the importance of insect pollination for seed production is lower at low elevations. Our findings indicate that the keystone species V. myrtillus is relatively robust to changes in the pollinator community in a warmer climate, thereby making it less vulnerable to climate-driven changes in plant-pollinator interactions.
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OBJECTIVES: The capability of a hospital's rapid response system (RRS) depends on various factors to reduce in-hospital cardiac arrests and mortality. Through system probing, this qualitative study targeted a more comprehensive understanding of how healthcare professionals manage the complexities of RRS in daily practice as well as identifying its challenges. METHODS: We observed RRS through in situ simulations in 2 wards and conducted the debriefings as focus group interviews. By arranging a separate focus group interview, we included the perspectives of intensive care unit personnel. RESULTS: Healthcare professionals appreciated the standardized use of the National Early Warning Score, when combined with clinical knowledge and experience, structured communication, and interprofessional collaboration. However, we identified salient challenges in RRS, for example, unwanted variation in recognition competence, and inconsistent routines in education and documentation. Furthermore, we found that a lack of interprofessional trust, different understandings of RRS protocol, and signs of low psychological safety in the wards disrupted collaboration. To help remedy identified challenges, healthcare professionals requested shared arenas for learning, such as in situ simulation training. CONCLUSIONS: Through system probing, we described the inner workings of RRS and revealed the challenges that require more attention. Healthcare professionals depend on structured RRS education, training, and resources to operate such a system. In this study, they request interventions like in situ simulation training as an interprofessional educational arena to improve patient care. This is a relevant field for further research. The Consolidated Criteria for Reporting Qualitative Studies Checklist was followed to ensure rigor in the study.
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Comunicação , Pessoal de Saúde , Hospitais , Humanos , Unidades de Terapia Intensiva , Relações Interprofissionais , Pesquisa QualitativaRESUMO
Background: Dry grasslands on calcareous bedrock in warm climates around the Oslo Fjord are naturally fragmented biodiversity hotspots. This habitat geographically coincides with the most densely populated area of Norway. Many habitat specialists, along with the habitat itself, are red-listed because of land-use change, forest encroachment, and invasive species that cause habitat loss and greater isolation of remaining patches. To ensure effective conservation, data on species presences and absences are necessary to quantify states, changes, and extinction risks in specific populations and habitat patches. New information: We present presence-absence data of 49 vascular plant species in 15 patches of dry calcareous grassland habitat, surveyed in 2009, 2019, and in 2020. The species are considered to be habitat specialists and, thus, unlikely to occur between the patches.
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Genetic differentiation and phenotypic plasticity jointly shape intraspecific trait variation, but their roles differ among traits. In short-lived plants, reproductive traits may be more genetically determined due to their impact on fitness, whereas vegetative traits may show higher plasticity to buffer short-term perturbations. Combining a multi-treatment greenhouse experiment with observational field data throughout the range of a widespread short-lived herb, Plantago lanceolata, we (1) disentangled genetic and plastic responses of functional traits to a set of environmental drivers and (2) assessed how genetic differentiation and plasticity shape observational trait-environment relationships. Reproductive traits showed distinct genetic differentiation that largely determined observational patterns, but only when correcting traits for differences in biomass. Vegetative traits showed higher plasticity and opposite genetic and plastic responses, masking the genetic component underlying field-observed trait variation. Our study suggests that genetic differentiation may be inferred from observational data only for the traits most closely related to fitness.
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Máscaras , Plantago , Adaptação Fisiológica , Biomassa , FenótipoRESUMO
Recreational use of nature areas is increasing worldwide. All trail-based activities have a certain degradation effect on vegetation and soil, and conflicts between conservation values and recreation may occur. Controversy still exists regarding the relative impact of mountain bikers compared to hikers on trails. In this study, we manipulated the use intensity from hikers and mountain bikers on existing, natural-surfaced trails, and investigated effects of increased use and the relative importance of mountain biking on trail degradation. In two study sites, two trails were selected, one designated for hiking and one for biking. Passes were counted with TRAFx counters. The proportion of mountain bikers on the designated biking trails was on average 47%, and on the hiking trails 13%. Trail width and depth were recorded at permanently marked transects repeatedly throughout the growing season, and analyzed with linear mixed models as a function of number of passes, proportion of bikers and environmental conditions along the trail. Trail width, both the core trail without vegetation and the total area influenced by trampling and biking, showed on average small, but highly variable increases with enhanced use. Trail widening occurred particularly in moist parts, and trail width increased more when a larger proportion of the passes was mountain bikers. Trail depth did not change much throughout the study period, suggesting that the soils along the trails were already compacted and to a limited degree prone to soil movement and subsequent soil loss. Our study shows that on-trail use by hikers and mountain bikers have relatively limited overall effects in terms of trail widening and deepening, but that effects depend highly on environmental conditions; enhanced use of trails in wet areas is likely to result in greater trail degradation, and more so if a large proportion of the users are mountain bikers. Management and maintenance of trails, in terms of re-routing or trail surface hardening, could thus be necessary to avoid negative impacts of increased use. For such management actions to be successful, they need to be targeted towards the actual user groups and the natural conditions in the area.
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Conservação dos Recursos Naturais , Recreação , Ciclismo , Estações do Ano , SoloRESUMO
When plants establish outside their native range, their ability to adapt to the new environment is influenced by both demography and dispersal. However, the relative importance of these two factors is poorly understood. To quantify the influence of demography and dispersal on patterns of genetic diversity underlying adaptation, we used data from a globally distributed demographic research network comprising 35 native and 18 nonnative populations of Plantago lanceolata Species-specific simulation experiments showed that dispersal would dilute demographic influences on genetic diversity at local scales. Populations in the native European range had strong spatial genetic structure associated with geographic distance and precipitation seasonality. In contrast, nonnative populations had weaker spatial genetic structure that was not associated with environmental gradients but with higher within-population genetic diversity. Our findings show that dispersal caused by repeated, long-distance, human-mediated introductions has allowed invasive plant populations to overcome environmental constraints on genetic diversity, even without strong demographic changes. The impact of invasive plants may, therefore, increase with repeated introductions, highlighting the need to constrain future introductions of species even if they already exist in an area.
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Fluxo Gênico , Variação Genética , Plantago/genética , Demografia , Espécies Introduzidas , Filogenia , Plantago/químicaRESUMO
Globally, many insect populations are declining, prompting calls for action. Yet these findings have also prompted discussion about sampling methods and interpretation of long-term datasets. As insect monitoring and research efforts increase, it is critical to quantify the effectiveness of sampling methods. This is especially true if sampling biases of different methods covary with climate, which is also changing over time. We assess the effectiveness of two types of flight intercept traps commonly used for beetles, a diverse insect group responsible for numerous ecosystem services, under different climatic conditions in Norwegian boreal forest. One of these trap designs includes a device to prevent rainwater from entering the collection vial, diluting preservatives and flushing out beetles. This design is compared to a standard trap. We ask how beetle capture rates vary between these traps, and how these differences vary based on precipitation levels and beetle body size, an important species trait. Bayesian mixed models reveal that the standard and modified traps differ in their beetle capture rates, but that the magnitude and direction of these differences change with precipitation levels and beetle body size. At low rainfall levels, standard traps catch more beetles, but as precipitation increases the catch rates of modified traps overtake those of standard traps. This effect is most pronounced for large-bodied beetles. Sampling methods are known to differ in their effectiveness. Here, we present evidence for a less well-known but likely common phenomenon-an interaction between climate and sampling, such that relative effectiveness of trap types for beetle sampling differs depending on precipitation levels and species traits. This highlights a challenge for long-term monitoring programs, where both climate and insect populations are changing. Sampling methods should be sought that eliminate climate interactions, any biases should be quantified, and all insect datasets should include detailed methodological metadata.
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BACKGROUND: Meta-analyses show that hospital rapid response systems (RRS) are associated with reduced rates of cardiorespiratory arrest and mortality. However, many RRS fail to provide appropriate outcomes. Thus an improved understanding of how to succeed with a RRS is crucial. By understanding the barriers and facilitators within the limbs of a RRS, these can be addressed. OBJECTIVE: To explore the barriers and facilitators within the limbs of a RRS as described by health-care professionals working within the system. METHODS: The electronic databases searched were: EMBASE, MEDLINE, CINAHL, Epistemonikos, Cochrane, PsychInfo and Web of Science. Search terms were related to RRS and their facilitators and barriers. Studies were appraised guided by the CASP tool. Twenty-one qualitative studies were identified and subjected to content analysis. RESULTS: Clear leadership, interprofessional trust and collaboration seems to be crucial for succeeding with a RRS. Clear protocols, feedback, continuous evaluation and interprofessional training were highlighted as facilitators. Reprimanding down the hierarchy, underestimating the importance of call-criteria, alarm fatigue and a lack of integration with other hospital systems were identified as barriers. CONCLUSION: To succeed with a RRS, the keys seem to lie in the administrative and quality improvement limbs. Clear leadership and continuous quality improvement provide the foundation for the continuing collaboration to manage deteriorating patients. Succeeding with a RRS is a never-ending process.
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Atitude do Pessoal de Saúde , Equipe de Respostas Rápidas de Hospitais/organização & administração , Qualidade da Assistência à Saúde , HumanosRESUMO
In climate change ecology, simplistic research approaches may yield unrealistically simplistic answers to often more complicated problems. In particular, the complexity of vegetation responses to global climate change begs a better understanding of the impacts of concomitant changes in several climatic drivers, how these impacts vary across different climatic contexts, and of the demographic processes underlying population changes. Using a replicated, factorial, whole-community transplant experiment, we investigated regional variation in demographic responses of plant populations to increased temperature and/or precipitation. Across four perennial forb species and 12 sites, we found strong responses to both temperature and precipitation change. Changes in population growth rates were mainly due to changes in survival and clonality. In three of the four study species, the combined increase in temperature and precipitation reflected nonadditive, antagonistic interactions of the single climatic changes for population growth rate and survival, while the interactions were additive and synergistic for clonality. This disparity affects the persistence of genotypes, but also suggests that the mechanisms behind the responses of the vital rates differ. In addition, survival effects varied systematically with climatic context, with wetter and warmer + wetter transplants showing less positive or more negative responses at warmer sites. The detailed demographic approach yields important mechanistic insights into how concomitant changes in temperature and precipitation affect plants, which makes our results generalizable beyond the four study species. Our comprehensive study design illustrates the power of replicated field experiments in disentangling the complex relationships and patterns that govern climate change impacts across real-world species and landscapes.
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Mudança Climática , Fenômenos Fisiológicos Vegetais , Tempo (Meteorologia) , Ecossistema , Dinâmica Populacional , Chuva , TemperaturaRESUMO
Globally accelerating trends in societal development and human environmental impacts since the mid-twentieth century 1-7 are known as the Great Acceleration and have been discussed as a key indicator of the onset of the Anthropocene epoch 6 . While reports on ecological responses (for example, changes in species range or local extinctions) to the Great Acceleration are multiplying 8, 9 , it is unknown whether such biotic responses are undergoing a similar acceleration over time. This knowledge gap stems from the limited availability of time series data on biodiversity changes across large temporal and geographical extents. Here we use a dataset of repeated plant surveys from 302 mountain summits across Europe, spanning 145 years of observation, to assess the temporal trajectory of mountain biodiversity changes as a globally coherent imprint of the Anthropocene. We find a continent-wide acceleration in the rate of increase in plant species richness, with five times as much species enrichment between 2007 and 2016 as fifty years ago, between 1957 and 1966. This acceleration is strikingly synchronized with accelerated global warming and is not linked to alternative global change drivers. The accelerating increases in species richness on mountain summits across this broad spatial extent demonstrate that acceleration in climate-induced biotic change is occurring even in remote places on Earth, with potentially far-ranging consequences not only for biodiversity, but also for ecosystem functioning and services.
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Altitude , Biodiversidade , Mapeamento Geográfico , Aquecimento Global/estatística & dados numéricos , Plantas/classificação , Europa (Continente) , História do Século XX , História do Século XXI , TemperaturaRESUMO
Biotic interactions are often ignored in assessments of climate change impacts. However, climate-related changes in species interactions, often mediated through increased dominance of certain species or functional groups, may have important implications for how species respond to climate warming and altered precipitation patterns. We examined how a dominant plant functional group affected the population dynamics of four co-occurring forb species by experimentally removing graminoids in seminatural grasslands. Specifically, we explored how the interaction between dominants and subordinates varied with climate by replicating the removal experiment across a climate grid consisting of 12 field sites spanning broad-scale temperature and precipitation gradients in southern Norway. Biotic interactions affected population growth rates of all study species, and the net outcome of interactions between dominants and subordinates switched from facilitation to competition with increasing temperature along the temperature gradient. The impacts of competitive interactions on subordinates in the warmer sites could primarily be attributed to reduced plant survival. Whereas the response to dominant removal varied with temperature, there was no overall effect of precipitation on the balance between competition and facilitation. Our findings suggest that global warming may increase the relative importance of competitive interactions in seminatural grasslands across a wide range of precipitation levels, thereby favouring highly competitive dominant species over subordinate species. As a result, seminatural grasslands may become increasingly dependent on disturbance (i.e. traditional management such as grazing and mowing) to maintain viable populations of subordinate species and thereby biodiversity under future climates. Our study highlights the importance of population-level studies replicated under different climatic conditions for understanding the underlying mechanisms of climate change impacts on plants.
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Mudança Climática , Pradaria , Veronica/fisiologia , Viola/fisiologia , Biodiversidade , Clima , Aquecimento Global , Noruega , Dinâmica PopulacionalRESUMO
Seedling recruitment is a critical life history stage for trees, and successful recruitment is tightly linked to both abiotic factors and biotic interactions. In order to better understand how tree species' distributions may change in response to anticipated climate change, more knowledge of the effects of complex climate and biotic interactions is needed. We conducted a seed-sowing experiment to investigate how temperature, precipitation and biotic interactions impact recruitment of Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) seedlings in southern Norway. Seeds were sown into intact vegetation and experimentally created gaps. To study the combined effects of temperature and precipitation, the experiment was replicated across 12 sites, spanning a natural climate gradient from boreal to alpine and from sub-continental to oceanic. Seedling emergence and survival were assessed 12 and 16 months after sowing, respectively, and above-ground biomass and height were determined at the end of the experiment. Interestingly, very few seedlings were detected in the boreal sites, and the highest number of seedlings emerged and established in the alpine sites, indicating that low temperature did not limit seedling recruitment. Site precipitation had an overall positive effect on seedling recruitment, especially at intermediate precipitation levels. Seedling emergence, establishment and biomass were higher in gap plots compared to intact vegetation at all temperature levels. These results suggest that biotic interactions in the form of competition may be more important than temperature as a limiting factor for tree seedling recruitment in the sub- and low-alpine zone of southern Norway.
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Clima , Picea/fisiologia , Pinus sylvestris/fisiologia , Biomassa , Mudança Climática , Temperatura Baixa , Noruega , Chuva , Plântula/fisiologia , Sementes/fisiologia , TemperaturaRESUMO
The salmon louse (Lepeoptheirus salmonis) is a challenge in the farming of Atlantic salmon (Salmo salar). To treat an infestation, different insecticides are used like the orally administered chitin synthetase inhibitor teflubenzuron. The concentrations and distribution of teflubenzuron were measured in water, organic particles, marine sediment and biota caught in the vicinity of a fish farm following a standard medication. Low concentrations were found in water samples whereas the organic waste from the farm, collected by sediment traps had concentrations higher than the medicated feed. Most of the organic waste was distributed to the bottom close to the farm but organic particles containing teflubenzuron were collected 1100 m from the farm. The sediment under the farm consisted of 5 to 10% organic material and therefore the concentration of teflubenzuron was much lower than in the organic waste. Teflubenzuron was persistent in the sediment with a stipulated halflife of 170 days. Sediment consuming polychaetes had high but decreasing concentrations of teflubenzuron throughout the experimental period, reflecting the decrease of teflubenzuron in the sediment. During medication most wild fauna contained teflubenzuron residues and where polychaetes and saith had highest concentrations. Eight months later only polychaetes and some crustaceans contained drug residues. What dosages that induce mortality in various crustaceans following short or long-term exposure is not known but the results indicate that the concentrations in defined individuals of king crab, shrimp, squat lobster and Norway lobster were high enough shortly after medication to induce mortality if moulting was imminent. Considering food safety, saith and the brown meat of crustaceans contained at first sampling concentrations of teflubenzuron higher than the MRL-value set for Atlantic salmon. The concentrations were, however, moderate and the amount of saith fillet or brown meat of crustaceans to be consumed in order to exceed ADI is relatively large.
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Aquicultura , Benzamidas/análise , Desinfetantes/análise , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Animais , Copépodes , Sedimentos Geológicos , Salmo salarRESUMO
Most range shift predictions focus on the dispersal phase of the colonization process. Because moving populations experience increasingly dissimilar nonclimatic environmental conditions as they track climate warming, it is also critical to test how individuals originating from contrasting thermal environments can establish in nonlocal sites. We assess the intraspecific variation in growth responses to nonlocal soils by planting a widespread grass of deciduous forests (Milium effusum) into an experimental common garden using combinations of seeds and soil sampled in 22 sites across its distributional range, and reflecting movement scenarios of up to 1600 km. Furthermore, to determine temperature and forest-structural effects, the plants and soils were experimentally warmed and shaded. We found significantly positive effects of the difference between the temperature of the sites of seed and soil collection on growth and seedling emergence rates. Migrant plants might thus encounter increasingly favourable soil conditions while tracking the isotherms towards currently 'colder' soils. These effects persisted under experimental warming. Rising temperatures and light availability generally enhanced plant performance. Our results suggest that abiotic and biotic soil characteristics can shape climate change-driven plant movements by affecting growth of nonlocal migrants, a mechanism which should be integrated into predictions of future range shifts.
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Clima , Aquecimento Global , Dispersão Vegetal , Poaceae/crescimento & desenvolvimento , Solo , Temperatura , Luz , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Sementes , ÁrvoresRESUMO
BACKGROUND: In Scandinavia, the knowledge base for murder-suicides is uneven, and there has been no statistics in criminal records. METHOD: We collected data from criminal registers in Norway from 1990 to 2007, and seek to compare this with international literature from the last 50 years. RESULTS: Over 90% of murder-suicide perpetrators are males and 80% of their victims are females. A vast majority of perpetrators are, or have been, intimate partners with their victim. The woman has often indicated an intention to break up from the relationship before the homicide. Compared with isolated homicides, the ages of both the perpetrator and victim are higher; most perpetrators use firearms, and tend to be less socially marginalized. Psychiatric instability is often a background factor, but should be seen in view of longstanding personal conflicts and threat of or loss of family, employment or social reputation. Norwegian statistics show that one in four murderers who have killed a near acquaintance also will commit suicide. CONCLUSIONS: Increased knowledge is essential to prevent further tragedies of murder-suicide. Scrutinizing the taboo surrounding the topic will probably lead to improved awareness. We suggest that a connection should be made between the homicide(s) and the suicide in criminal registers.