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1.
BMC Health Serv Res ; 20(1): 107, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32046710

RESUMO

BACKGROUND: Clinical practice improvements based on quality-register data are influenced by multiple factors. Although there is agreement that information from quality registers is valuable for quality improvement, practical ways of organising register use have been notoriously difficult to realise. The present study sought to investigate the mechanisms that lead various clinicians to use quality registers for improvement. METHODS: This research involves studying individuals' decisions in response to a Swedish programme focusing on increasing the use of quality registers. Through a case study, we focused on heart failure care and its corresponding register: the Swedish Heart Failure Register. The empirical data consisted of a purposive sample collected longitudinally by qualitative methods between 2013 and 2015. In total, 18 semi-structured interviews were carried out. We used realist evaluation to identify contexts, mechanisms, and outcomes. RESULTS: We identified four contexts - registration, use of output data, governance, and improvement projects - that provide conditions for the initiation of specific mechanisms. Given a professional theoretical perspective, we further showed that mechanisms are based on the logics of either organisational improvement or clinical practice. The two logics offer insights into the ways in which clinicians choose to embrace or reject certain registers' initiatives. CONCLUSIONS: We identified a strong path dependence, as registers have historically been tightly linked to the medical profession's competence. Few new initiatives in the studied programme reach the clinical context. We explain this through the lack of an organisational improvement logic and its corresponding mechanisms in the context of the medical profession. Implementation programmes must understand the logic of clinical practice; that is, be integrated with the ways in which work is carried out in everyday practice. Programmes need to be better at helping core health professionals to reach the highest standards of patient care.

2.
Nat Commun ; 10(1): 4955, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31672989

RESUMO

Systemic sclerosis (SSc) is an autoimmune disease that shows one of the highest mortality rates among rheumatic diseases. We perform a large genome-wide association study (GWAS), and meta-analysis with previous GWASs, in 26,679 individuals and identify 27 independent genome-wide associated signals, including 13 new risk loci. The novel associations nearly double the number of genome-wide hits reported for SSc thus far. We define 95% credible sets of less than 5 likely causal variants in 12 loci. Additionally, we identify specific SSc subtype-associated signals. Functional analysis of high-priority variants shows the potential function of SSc signals, with the identification of 43 robust target genes through HiChIP. Our results point towards molecular pathways potentially involved in vasculopathy and fibrosis, two main hallmarks in SSc, and highlight the spectrum of critical cell types for the disease. This work supports a better understanding of the genetic basis of SSc and provides directions for future functional experiments.

3.
Leadersh Health Serv (Bradf Engl) ; 32(4): 525-542, 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31612790

RESUMO

PURPOSE: The purpose of this paper is to evaluate behavioural changes and operational outcomes resulting from a Master's programme on improvement knowledge and leadership in the Swedish welfare sector. The welfare sector is the collective term for tax-funded services the state, county councils and municipalities are responsible to provide. DESIGN/METHODOLOGY/APPROACH: A survey combined open-ended and closed questions using a five-point Likert scale. The questions were based on the learning objectives of the Master's programme. The survey was sent to 139 graduates and achieved a response rate of 41 per cent (57 respondents). Responses were entered into a survey programme to enable the descriptive presentation of data; open-ended responses were analysed using conventional content analysis. FINDINGS: Respondents reported their increased knowledge and changed behaviours had impacted operational outcomes, e.g. processes efficiency, compliance with guidelines and quality. They said the programme was of value to themselves and society but requested more leadership knowledge. All respondents recommended the programme to others. ORIGINALITY/VALUE: By operationalizing the Kirkpatrick framework, the paper describes outcomes on levels three and four, and the use of numerous best practice techniques for adult learning. This is valuable knowledge for organisers of improvement knowledge educations.

4.
Health Expect ; 22(6): 1240-1250, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31433546

RESUMO

BACKGROUND: An improvement initiative sought to improve care for atrial fibrillation (AF) patients; many felt insecure about how to cope with AF. OBJECTIVE: To reveal AF patients' and professionals' experiences of pilot-testing a Learning Café group education programme, aimed at increasing the patients' sense of security in everyday life. DESIGN: Using an organizational case study design, we combined quantitative data (patients' sense of security) and qualitative data (project documentation; focus group interviews with five patients and five professionals) analysed using inductive qualitative content analysis. SETTING: AF patients and a multiprofessional team at a cardiac care unit in a Swedish district hospital. IMPROVEMENT ACTIVITIES: Two registered nurses invited AF patients and partners to four 2.5-hour Learning Café sessions. In the first session, they solicited participants' questions about life with AF. A physician, a registered nurse and a physiotherapist were invited to address these questions in the remaining sessions. RESULTS: AF patients reported gaining a greater sense of security in everyday life and anticipating a future shift from emergency care to planned care. Professionals reported enhanced professional development, learning more about person-centredness and gaining greater control of their own work situation. The organization gained knowledge about patient and family involvement. CONCLUSIONS: The Learning Café pilot test-exemplifying movement towards co-production through patient-professional collaboration-generated positive outcomes for patients (sense of security), professionals (work satisfaction; learning) and the organization (better care) in line with contemporary models for quality improvement and with Self-Determination Theory. This approach merits further testing and evaluation in other contexts.

5.
Implement Sci ; 14(1): 74, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31337394

RESUMO

BACKGROUND: Quality improvement collaboratives (QICs) are widely used to improve healthcare, but there are few studies of long-term sustained improved outcomes, and inconsistent evidence about what factors contribute to success. The aim of the study was to open the black box of QICs and compare characteristics and activities in detail of two differing QICs in relation to their changed outcomes from baseline and the following 3 years. METHODS: Final reports of two QICs-one on heart failure care with five teams, and one on osteoarthritis care with seven teams, including detailed descriptions of improvement projects from each QIC's team, were analysed and coded by 18 QIC characteristics and four team characteristics. Goal variables from each team routinely collected within the Swedish Heart Failure Registry (SwedeHF) and the Better Management of Patients with OsteoArthritis Registry (BOA) at year 2013 (baseline), 2014, 2015 and 2016 were analysed with univariate statistics. RESULTS: The two QICs differed greatly in design. The SwedeHF-QIC involved eight experts and ran for 12 months, whereas the BOA-QIC engaged three experts and ran for 6 months. There were about twice as many activities in the SwedeHF-QIC as in the BOA-QIC and they ranged from standardisation of team coordination to better information and structured follow-ups. The outcome results were heterogeneous within teams and across teams and QICs. Both QICs were highly appreciated by the participants and contributed to their learning, e.g. of improvement methods; however, several teams had already reached goal values when the QICs were launched in 2013. CONCLUSIONS: Even though many QI activities were carried out, it was difficult to see sustained improvements on outcomes. Outcomes as specific measurable aspects of care in need of improvement should be chosen carefully. Activities focusing on adherence to standard care programmes and on increased follow-up of patients seemed to lead to more long-lasting improvements. Although earlier studies showed that data follow-up and measurement skills as well as well-functioning data warehouses contribute to sustained improvements, the present registries' functionality and QICs at this time did not support those aspects sufficiently. Further studies on QICs and their impact on improvement beyond the project time should investigate the effect of those elements in particular.


Assuntos
Comportamento Cooperativo , Insuficiência Cardíaca/terapia , Osteoartrite/terapia , Equipe de Assistência ao Paciente/organização & administração , Melhoria de Qualidade/organização & administração , Sistema de Registros , Humanos , Avaliação de Programas e Projetos de Saúde , Suécia , Fatores de Tempo
6.
Glob Chang Biol ; 25(9): 2900-2914, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31166650

RESUMO

There is evidence that anthropogenic nitrogen (N) deposition enhances carbon (C) sequestration in boreal forest soils. However, it is unclear how free-living saprotrophs (bacteria and fungi, SAP) and ectomycorrhizal (EM) fungi responses to N addition impact soil C dynamics. Our aim was to investigate how SAP and EM communities are impacted by N enrichment and to estimate whether these changes influence decay of litter and humus. We conducted a long-term experiment in northern Sweden, maintained since 2004, consisting of ambient, low N additions (0, 3, 6, and 12 kg N ha-1  year-1 ) simulating current N deposition rates in the boreal region, as well as a high N addition (50 kg N ha-1  year-1 ). Our data showed that long-term N enrichment impeded mass loss of litter, but not of humus, and only in response to the highest N addition treatment. Furthermore, our data showed that EM fungi reduced the mass of N and P in both substrates during the incubation period compared to when only SAP organisms were present. Low N additions had no effect on microbial community structure, while the high N addition decreased fungal and bacterial biomasses and altered EM fungi and SAP community composition. Actinomycetes were the only bacterial SAP to show increased biomass in response to the highest N addition. These results provide a mechanistic understanding of how anthropogenic N enrichment can influence soil C accumulation rates and suggest that current N deposition rates in the boreal region (≤12 kg N ha-1  year-1 ) are likely to have a minor impact on the soil microbial community and the decomposition of humus and litter.


Assuntos
Micorrizas , Nitrogênio , Carbono , Solo , Microbiologia do Solo , Suécia
8.
PLoS One ; 13(10): e0205296, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30335770

RESUMO

Atmospheric deposition of nitrogen (N) influences forest demographics and carbon (C) uptake through multiple mechanisms that vary among tree species. Prior studies have estimated the effects of atmospheric N deposition on temperate forests by leveraging forest inventory measurements across regional gradients in deposition. However, in the United States (U.S.), these previous studies were limited in the number of species and the spatial scale of analysis, and did not include sulfur (S) deposition as a potential covariate. Here, we present a comprehensive analysis of how tree growth and survival for 71 species vary with N and S deposition across the conterminous U.S. Our analysis of 1,423,455 trees from forest plots inventoried between 2000 and 2016 reveals that the growth and/or survival of the vast majority of species in the analysis (n = 66, or 93%) were significantly affected by atmospheric deposition. Species co-occurred across the conterminous U.S. that had decreasing and increasing relationships between growth (or survival) and N deposition, with just over half of species responding negatively in either growth or survival to increased N deposition somewhere in their range (42 out of 71). Averaged across species and conterminous U.S., however, we found that an increase in deposition above current rates of N deposition would coincide with a small net increase in tree growth (1.7% per Δ kg N ha-1 yr-1), and a small net decrease in tree survival (-0.22% per Δ kg N ha-1 yr-1), with substantial regional and among-species variation. Adding S as a predictor improved the overall model performance for 70% of the species in the analysis. Our findings have potential to help inform ecosystem management and air pollution policy across the conterminous U.S., and suggest that N and S deposition have likely altered forest demographics in the U.S.


Assuntos
Modelos Estatísticos , Nitrogênio/metabolismo , Enxofre/metabolismo , Árvores/metabolismo , Carbono/química , Carbono/metabolismo , Simulação por Computador , Florestas , Nitrogênio/química , Solo/química , Enxofre/química , Árvores/química , Árvores/crescimento & desenvolvimento , Estados Unidos
9.
Leadersh Health Serv (Bradf Engl) ; 31(4): 371-383, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30234448

RESUMO

Purpose The purpose of this study is to examine and establish how sensemaking develops among a group of external change agents (ECAs) engaged to disseminate a national quality register nationwide in Swedish health care and elderly care. To study the emergent sensemaking, the theoretical concept of cognitive shift has been used. Design/methodology/approach The data collection method included individual semi-structured interviews, and two sets of interviews (initial sensemaking and renewed sensemaking) have been conducted. Based on a typology describing how ECAs interpret their work, structural analyses and comparisons of initial and renewed sensemaking are made and illuminated in spider diagrams. The data are then analyzed to search for cognitive shifts. Findings The ECAs' sensemaking develops. Three cognitive shifts are identified, and a new kind of issue-related cognitive shift, the outcome-related cognitive shift, is suggested. For the ECAs to customize their work, they need to be aware of how they interpret their own work and how these interpretations develop over time. Originality/value The study takes a novel view of the interrelated concepts of sensemaking and sensegivers and points out the cognitive shifts as a helpful theoretical concept to study how sensemaking develops.


Assuntos
Cognição , Serviços de Saúde para Idosos/tendências , Inovação Organizacional , Gestão da Qualidade Total , Comunicação , Humanos , Entrevistas como Assunto , Modelos Psicológicos , Papel Profissional , Sistema de Registros , Suécia
10.
Leadersh Health Serv (Bradf Engl) ; 31(4): 398-408, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30234450

RESUMO

Purpose The purpose of this paper is to examine how external change agents (ECAs) engaged to disseminate a national quality register (NQR) called Senior alert nationwide in the Swedish health care and elderly care sectors interpret their work. To study this, sensemaking theories are used. Design/methodology/approach This is a qualitative inductive interview study including eight ECAs. To analyze the data, a thematic analysis is carried out. Findings Well-disseminated NQRs support health care organizations' possibility to work with quality improvement and to improve care for patient groups. NQRs function as artifacts that can influence how health care professionals make sense of their work. In this paper, a typology depicting how the ECAs make sense of their dissemination work has been developed. The ECAs are engaged in prospective sensemaking. They describe their work as being about creating future good results, both for patients and affiliated organizations, and they can balance different quality aspects. Originality/value The number of NQRs increased markedly in Sweden and elsewhere, but there are few reports on how health care professionals working with the registers interpret their work. The use of ECAs to disseminate NQRs is a novel approach. This paper describes how the ECAs are engaged in prospective sensemaking - an under-researched perspective of the sensemaking theory.


Assuntos
Serviços de Saúde para Idosos/normas , Disseminação de Informação , Sistema de Registros , Gestão da Qualidade Total , Humanos , Pesquisa Qualitativa , Suécia
11.
Environ Pollut ; 242(Pt B): 1787-1799, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30115529

RESUMO

Understorey communities can dominate forest plant diversity and strongly affect forest ecosystem structure and function. Understoreys often respond sensitively but inconsistently to drivers of ecological change, including nitrogen (N) deposition. Nitrogen deposition effects, reflected in the concept of critical loads, vary greatly not only among species and guilds, but also among forest types. Here, we characterize such context dependency as driven by differences in the amounts and forms of deposited N, cumulative deposition, the filtering of N by overstoreys, and available plant species pools. Nitrogen effects on understorey trajectories can also vary due to differences in surrounding landscape conditions; ambient browsing pressure; soils and geology; other environmental factors controlling plant growth; and, historical and current disturbance/management regimes. The number of these factors and their potentially complex interactions complicate our efforts to make simple predictions about how N deposition affects forest understoreys. We review the literature to examine evidence for context dependency in N deposition effects on forest understoreys. We also use data from 1814 European temperate forest plots to test the ability of multi-level models to characterize context-dependent understorey responses across sites that differ in levels of N deposition, community composition, local conditions and management history. This analysis demonstrated that historical management, and plot location on light and pH-fertility gradients, significantly affect how understorey communities respond to N deposition. We conclude that species' and communities' responses to N deposition, and thus the determination of critical loads, vary greatly depending on environmental contexts. This complicates our efforts to predict how N deposition will affect forest understoreys and thus how best to conserve and restore understorey biodiversity. To reduce uncertainty and incorporate context dependency in critical load setting, we should assemble data on underlying environmental conditions, conduct globally distributed field experiments, and analyse a wider range of habitat types.


Assuntos
Florestas , Nitrogênio/análise , Biodiversidade , Ecossistema , Ciclo do Nitrogênio , Plantas , Solo , Árvores/crescimento & desenvolvimento
12.
Water Res ; 144: 474-481, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30075443

RESUMO

Over four billion people are discharging untreated human excreta into the environment without any prior treatment, causing eutrophication and spreading disease. The most nutrient rich fraction is the urine. Urine can be collected separately and dehydrated in an alkaline bed producing a nutrient rich fertiliser. However, faecal cross-contamination during the collection risks to introduce pathogens to the urine. The objective of this hygiene assessment was to study the inactivation of five microorganisms (Ascaris suum, Enterococcus faecalis, bacteriophages MS2 and ΦX 174 and Salmonella spp) in alkaline dehydrated urine. Fresh human urine was dehydrated in wood ash at 42 °C until the pH decreased to ≤10.5, at which point the saturated ash was inoculated with faeces containing the microorganisms and left open to the air (mimicking stockpiling of the end product) at temperatures of 20 and 42 °C. The bacteria and bacteriophages were inactivated to below the detection limit (100 cfu ml-1 for bacteria; 10 pfu mL-1 for bacteriophages) within four days storage at 20 °C. A. suum inactivation data was fitted to a non-linear regression model, which estimated a required 325 days of storage at 20 °C and 9.2 days at 42 °C to reach a 3 log10 reduction. However, the urine dehydration in itself achieved a concentration <1 A. suum per 4 g of dehydrated medium which fulfil the WHO guidelines for unrestricted use.


Assuntos
Dessecação/métodos , Desinfecção/métodos , Urina/química , Animais , Ascaris suum , Bacteriófago phi X 174 , Enterococcus faecalis , Fezes/microbiologia , Fertilizantes , Humanos , Concentração de Íons de Hidrogênio , Levivirus , Salmonella , Temperatura Ambiente , Urina/microbiologia , Urina/parasitologia , Urina/virologia
13.
Water Res ; 142: 325-336, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29890480

RESUMO

In urine-separating sanitation systems, bacterial urease enzymes can hydrolyse urea to ammonia during the pipe transport and storage of urine. The present study investigated whether it was possible to reduce the urine volume without losing the nitrogen as ammonia. A method for stabilising the urine prior to dehydration was developed. Briefly, fresh human urine was stabilised by passage through an anion-exchanger, added to an alkaline media (wood ash or alkalised biochar), and dehydrated. Urine dehydration was investigated at three temperatures: 40, 45 and 50 °C. The influence of various factors affecting the dehydration process was modelled and the rate of urine dehydration was optimised. Results indicated that 75% (v/v) of the urine has to pass through the ion-exchanger for alkaline stabilisation of urine to occur. At all investigated temperatures, the dehydrator accomplished >90% volume reduction of ion-exchanged urine, > 70% N retention and 100% recovery of P and K. To realise high degree of nutrient valorisation, this study proposes combining source-separation of human urine with alkaline dehydration.


Assuntos
Nitrogênio/química , Fósforo/química , Potássio/química , Urina/química , Eliminação de Resíduos Líquidos/métodos , Adulto , Idoso , Amônia/química , Dessecação , Feminino , Humanos , Hidrólise , Troca Iônica , Masculino , Pessoa de Meia-Idade , Temperatura Ambiente , Ureia/química , Adulto Jovem
14.
J Environ Manage ; 210: 1-9, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29329003

RESUMO

We evaluated the long-term implications from modifying rotation lengths in production forests for four forest-reliant species with different habitat requirements. By combining simulations of forest development with habitat models, and accounting both for stand and landscape scale influences, we projected habitat availability over 150 years in a large Swedish landscape, using rotation lengths which are longer (+22% and +50%) and shorter (-22%) compared to current practices. In terms of mean habitat availability through time, species requiring older forest were affected positively by extended rotations, and negatively by shortened rotations. For example, the mean habitat area for the treecreeper Certhia familiaris (a bird preferring forest with larger trees) increased by 31% when rotations were increased by 22%, at a 5% cost to net present value (NPV) and a 7% decrease in harvested volume. Extending rotation lengths by 50% provided more habitat for this species compared to a 22% extension, but at a much higher marginal cost. In contrast, the beetle Hadreule elongatula, which is dependent on sun-exposed dead wood, benefited from shortened rather than prolonged rotations. Due to an uneven distribution of stand-ages within the landscape, the relative amounts of habitat provided by different rotation length scenarios for a given species were not always consistent through time during the simulation period. If implemented as a conservation measure, prolonging rotations will require long-term strategic planning to avoid future bottlenecks in habitat availability, and will need to be accompanied by complementary measures accounting for the diversity of habitats necessary for the conservation of forest biodiversity.


Assuntos
Conservação dos Recursos Naturais , Agricultura Florestal , Animais , Ecossistema , Florestas , Suécia , Árvores
15.
J Eval Clin Pract ; 23(6): 1329-1335, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28748651

RESUMO

RATIONALE, AIM, AND OBJECTIVE: This study aimed to explore programme theories of a national quality register. A programme theory is a bundle of assumptions underpinning how and why an improvement initiative functions. The purpose was to examine and establish programme theories of a national quality register widely used in Sweden: Senior alert. The paper reports on how programme theories among change recipients emerge in relation to the established programme theory of the initiator. METHODS: A qualitative approach and a longitudinal research design were used. To develop programme theories among change recipients, individual semistructured interviews were conducted. Three sets of interviews were conducted in the period of 2011 to 2013, totalling 22 interviews. In addition, 4 participant observations were made. To develop the initiator's programme theory, an iterative multistage collaboration process between the researchers and the initiator was used. A directed content analysis was used to analyse data. FINDINGS: The initiator and change recipients described similar programme logics, but differing programme theories. With time, change recipients' programme theories emerged. Their programme theories converged and became more like the programme theory of the initiator. CONCLUSIONS: This study has demonstrated the importance of making both the initiator's and change recipients' programme theories explicit. To learn about conditions for improvement initiatives, comparisons between their programme theories are valuable. Differences in programme theories provide information on how initiators can customize support for their improvement initiatives. Similar programme logics can be underpinned by different programme theories, which can be deceptive. Programme theories emerge over time and need to be understood as dynamic phenomena.


Assuntos
Idoso Fragilizado , Pessoal de Saúde/organização & administração , Serviços de Saúde para Idosos/organização & administração , Qualidade da Assistência à Saúde/organização & administração , Sistema de Registros , Idoso , Idoso de 80 Anos ou mais , Prática Clínica Baseada em Evidências , Pessoal de Saúde/normas , Serviços de Saúde para Idosos/normas , Humanos , Entrevistas como Assunto , Estudos Longitudinais , Pesquisa Qualitativa , Qualidade da Assistência à Saúde/normas , Medição de Risco , Suécia
16.
Sci Rep ; 7(1): 4083, 2017 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-28642496

RESUMO

In nitrogen (N) limited boreal forests, N enrichment can impact litter decomposition by affecting litter quality and by changing the soil environment where litter decomposes. We investigated the importance of litter quality and soil factors on litter decomposition using a 2-year reciprocal transplant experiment for Picea abies needle litter, derived from plots subjected to 17 years of N addition, including control, low and high N treatments (ambient, 12.5 and 50 kg N ha-1 yr-1, respectively). Our data show that changes in soil factors were the main pathway through which N impacted litter decomposition, with rates reduced by ~15% when placed in high N relative to control plots, regardless of litter origin. Litter decomposition was correlated to soil microbiota, with Picea abies litter decomposition positively correlated with gram negative and fungal functional groups. Our results suggest that previous findings of increase soil C accumulation in response to N deposition is likely to occur as a result of changes in soil microbiota rather than altered litter quality.

17.
Ecol Appl ; 27(6): 1838-1851, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28464423

RESUMO

We report results from long-term simulated external nitrogen (N) input experiments in three northern Pinus sylvestris forests, two of moderately high and one of moderately low productivity, assessing effects on annual net primary production (NPP) of woody mass and its interannual variation in response to variability in weather conditions. A sigmoidal response of wood NPP to external N inputs was observed in the both higher and lower productivity stands, reaching a maximum of ~65% enhancement regardless of the native site productivity, saturating at an external N input of 4-5 g N·m-2 ·yr-1 . The rate of increase in wood NPP and the N response efficiency (REN , increase in wood NPP per external N input) were maximized at an external N input of ~3 g N·m-2 ·yr-1 , regardless of site productivity. The maximum REN was greater in the higher productivity than the lower productivity stand (~20 vs. ~14 g C/g N). The N-induced enhancement of wood NPP and its REN were, however, markedly contingent on climatic variables. In both of the higher and lower productivity stands, wood NPP increased with growing season precipitation (P), but only up to ~400 mm. The sensitivity of the response to P increased with increasing external N inputs. Increasing growing season temperature (T) somewhat increased the N-induced drought effect, whereas decreasing T reduced the drought effect. These responses of wood NPP infused a large temporal variation to REN , making the use of a fixed value unadvisable. Based on these results, we suggest that regional climate conditions and future climate scenarios should be considered when modeling carbon sequestration in response to N deposition in boreal P. sylvestris, and possibly other forests.


Assuntos
Sequestro de Carbono , Clima , Florestas , Nitrogênio/metabolismo , Pinus sylvestris/metabolismo , Noruega , Estações do Ano , Suécia , Árvores/metabolismo , Madeira/química , Madeira/metabolismo
18.
J Environ Manage ; 197: 404-414, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28411568

RESUMO

A variety of modeling approaches can be used to project the future development of forest systems, and help to assess the implications of different management alternatives for biodiversity and ecosystem services. This diversity of approaches does however present both an opportunity and an obstacle for those trying to decide which modeling technique to apply, and interpreting the management implications of model output. Furthermore, the breadth of issues relevant to addressing key questions related to forest ecology, conservation biology, silviculture, economics, requires insights stemming from a number of distinct scientific disciplines. As forest planners, conservation ecologists, ecological economists and silviculturalists, experienced with modeling trade-offs and synergies between biodiversity and wood biomass production, we identified fifteen key considerations relevant to assessing the pros and cons of alternative modeling approaches. Specifically we identified key considerations linked to study question formulation, modeling forest dynamics, forest processes, study landscapes, spatial and temporal aspects, and the key response metrics - biodiversity and wood biomass production, as well as dealing with trade-offs and uncertainties. We also provide illustrative examples from the modeling literature stemming from the key considerations assessed. We use our findings to reiterate the need for explicitly addressing and conveying the limitations and uncertainties of any modeling approach taken, and the need for interdisciplinary research efforts when addressing the conservation of biodiversity and sustainable use of environmental resources.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Florestas , Ecossistema , Madeira
19.
Ambio ; 46(3): 324-334, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28236260

RESUMO

Because of the limited spatial extent and comprehensiveness of protected areas, an increasing emphasis is being placed on conserving habitats which promote biodiversity within production forest. For this reason, alternative silvicultural programs need to be evaluated with respect to their implications for forest biodiversity, especially if these programs are likely to be adopted. Here we simulated the effect of varied rotation length and associated thinning regimes on habitat availability in Scots pine and Norway spruce production forests, with high and low productivity. Shorter rotation lengths reduced the contribution made by production trees (trees grown for industrial use) to the availability of key habitat features, while concurrently increasing the contribution from retention trees. The contribution of production trees to habitat features was larger for high productivity sites, than for low productivity sites. We conclude that shortened rotation lengths result in losses of the availability of habitat features that are key for biodiversity conservation and that increased retention practices may only partially compensate for this. Ensuring that conservation efforts better reflect the inherent variation in stand rotation lengths would help improve the maintenance of key forest habitats in production forests.


Assuntos
Conservação dos Recursos Naturais/métodos , Agricultura Florestal/métodos , Modelos Teóricos , Picea , Pinus , Simulação por Computador , Florestas , Árvores
20.
PLoS One ; 11(8): e0162086, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27580120

RESUMO

There is evidence that anthropogenic nitrogen (N) deposition enhances carbon (C) sequestration in boreal soils. However, key underlying mechanisms explaining this increase have not been resolved. Two potentially important mechanisms are that aboveground litter production increases, or that litter quality changes in response to N enrichment. As such, our aim was to quantify whether simulated chronic N deposition caused changes in aboveground litter production or quality in a boreal forest. We conducted a long-term (17 years) stand-scale (0.1 ha) forest experiment, consisting of three N addition levels (0, 12.5, and 50 kg N ha-1 yr-1) in northern Sweden, where background N deposition rates are very low. We measured the annual quantity of litter produced for 8 different litter categories, as well as their concentrations of C, N, phosphorus (P), lignin, cellulose and hemi-cellulose. Our results indicate that mosses were the only major litter component showing significant quantitative and qualitative alterations in response to the N additions, indicative of their ability to intercept a substantial portion of the N added. These effects were, however, offset by the other litter fractions where we found no changes in the total litter fluxes, or individual chemical constituents when all litter categories were summed. This study indicates that the current annual litter fluxes cannot explain the increase in soil C that has occurred in our study system in response to simulated chronic N application. These results suggest that other mechanisms are likely to explain the increased soil C accumulation rate we have observed, such as changes in soil microbial activity, or potentially transient changes in aboveground litter inputs that were no longer present at the time of our study.


Assuntos
Briófitas/fisiologia , Nitrogênio/análise , Solo/química , Briófitas/química , Carbono/análise , Ecossistema , Suécia , Taiga
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