Hasil untuk "Physical geography"

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S2 Open Access 2018
Physical Activity and Incident Depression: A Meta-Analysis of Prospective Cohort Studies.

F. Schuch, D. Vancampfort, J. Firth et al.

OBJECTIVE The authors examined the prospective relationship between physical activity and incident depression and explored potential moderators. METHOD Prospective cohort studies evaluating incident depression were searched from database inception through Oct. 18, 2017, on PubMed, PsycINFO, Embase, and SPORTDiscus. Demographic and clinical data, data on physical activity and depression assessments, and odds ratios, relative risks, and hazard ratios with 95% confidence intervals were extracted. Random-effects meta-analyses were conducted, and the potential sources of heterogeneity were explored. Methodological quality was assessed using the Newcastle-Ottawa Scale. RESULTS A total of 49 unique prospective studies (N=266,939; median proportion of males across studies, 47%) were followed up for 1,837,794 person-years. Compared with people with low levels of physical activity, those with high levels had lower odds of developing depression (adjusted odds ratio=0.83, 95% CI=0.79, 0.88; I2=0.00). Furthermore, physical activity had a protective effect against the emergence of depression in youths (adjusted odds ratio=0.90, 95% CI=0.83, 0.98), in adults (adjusted odds ratio=0.78, 95% CI=0.70, 0.87), and in elderly persons (adjusted odds ratio=0.79, 95% CI=0.72, 0.86). Protective effects against depression were found across geographical regions, with adjusted odds ratios ranging from 0.65 to 0.84 in Asia, Europe, North America, and Oceania, and against increased incidence of positive screen for depressive symptoms (adjusted odds ratio=0.84, 95% CI=0.79, 0.89) or major depression diagnosis (adjusted odds ratio=0.86, 95% CI=0.75, 0.98). No moderators were identified. Results were consistent for unadjusted odds ratios and for adjusted and unadjusted relative risks/hazard ratios. Overall study quality was moderate to high (Newcastle-Ottawa Scale score, 6.3). Although significant publication bias was found, adjusting for this did not change the magnitude of the associations. CONCLUSIONS Available evidence supports the notion that physical activity can confer protection against the emergence of depression regardless of age and geographical region.

1358 sitasi en Psychology, Medicine
S2 Open Access 2017
The effect of physical activity on mortality and cardiovascular disease in 130 000 people from 17 high-income, middle-income, and low-income countries: the PURE study.

S. Lear, Weihong Hu, S. Rangarajan et al.

BACKGROUND Physical activity has a protective effect against cardiovascular disease (CVD) in high-income countries, where physical activity is mainly recreational, but it is not known if this is also observed in lower-income countries, where physical activity is mainly non-recreational. We examined whether different amounts and types of physical activity are associated with lower mortality and CVD in countries at different economic levels. METHODS In this prospective cohort study, we recruited participants from 17 countries (Canada, Sweden, United Arab Emirates, Argentina, Brazil, Chile, Poland, Turkey, Malaysia, South Africa, China, Colombia, Iran, Bangladesh, India, Pakistan, and Zimbabwe). Within each country, urban and rural areas in and around selected cities and towns were identified to reflect the geographical diversity. Within these communities, we invited individuals aged between 35 and 70 years who intended to live at their current address for at least another 4 years. Total physical activity was assessed using the International Physical Activity Questionnaire (IPQA). Participants with pre-existing CVD were excluded from the analyses. Mortality and CVD were recorded during a mean of 6·9 years of follow-up. Primary clinical outcomes during follow-up were mortality plus major CVD (CVD mortality, incident myocardial infarction, stroke, or heart failure), either as a composite or separately. The effects of physical activity on mortality and CVD were adjusted for sociodemographic factors and other risk factors taking into account household, community, and country clustering. FINDINGS Between Jan 1, 2003, and Dec 31, 2010, 168 916 participants were enrolled, of whom 141 945 completed the IPAQ. Analyses were limited to the 130 843 participants without pre-existing CVD. Compared with low physical activity (3000 MET × minutes or >750 minutes per week) were associated with graded reduction in mortality (hazard ratio 0·80, 95% CI 0·74-0·87 and 0·65, 0·60-0·71; p<0·0001 for trend), and major CVD (0·86, 0·78-0·93; p<0·001 for trend). Higher physical activity was associated with lower risk of CVD and mortality in high-income, middle-income, and low-income countries. The adjusted population attributable fraction for not meeting the physical activity guidelines was 8·0% for mortality and 4·6% for major CVD, and for not meeting high physical activity was 13·0% for mortality and 9·5% for major CVD. Both recreational and non-recreational physical activity were associated with benefits. INTERPRETATION Higher recreational and non-recreational physical activity was associated with a lower risk of mortality and CVD events in individuals from low-income, middle-income, and high-income countries. Increasing physical activity is a simple, widely applicable, low cost global strategy that could reduce deaths and CVD in middle age. FUNDING Population Health Research Institute, the Canadian Institutes of Health Research, Heart and Stroke Foundation of Ontario, Ontario SPOR Support Unit, Ontario Ministry of Health and Long-Term Care, AstraZeneca, Sanofi-Aventis, Boehringer Ingelheim, Servier, GSK, Novartis, King Pharma, and national and local organisations in participating countries that are listed at the end of the Article.

1043 sitasi en Medicine
S2 Open Access 2024
National, regional, and global trends in insufficient physical activity among adults from 2000 to 2022: a pooled analysis of 507 population-based surveys with 5·7 million participants

T. Strain, Seth Flaxman, R. Guthold et al.

Summary Background Insufficient physical activity increases the risk of non-communicable diseases, poor physical and cognitive function, weight gain, and mental ill-health. Global prevalence of adult insufficient physical activity was last published for 2016, with limited trend data. We aimed to estimate the prevalence of insufficient physical activity for 197 countries and territories, from 2000 to 2022. Methods We collated physical activity reported by adults (aged ≥18 years) in population-based surveys. Insufficient physical activity was defined as not doing 150 minutes of moderate-intensity activity, 75 minutes of vigorous-intensity activity, or an equivalent combination per week. We used a Bayesian hierarchical model to compute estimates of insufficient physical activity by country or territory, year, age, and sex. We assessed whether countries or territories, regions, and the world would meet the global target of a 15% relative reduction of the prevalence of insufficient physical activity by 2030 if 2010–22 trends continue. Findings We included 507 surveys across 163 countries and territories. The global age-standardised prevalence of insufficient physical activity was 31·3% (95% uncertainty interval 28·6–34·0) in 2022, an increase from 23·4% (21·1–26·0) in 2000 and 26·4% (24·8–27·9) in 2010. Prevalence was increasing in 103 (52%) of 197 countries and territories and six (67%) of nine regions, and was declining in the remainder. Prevalence was 5 percentage points higher among female (33·8% [29·9–37·7]) than male (28·7% [25·0–32·6]) individuals. Insufficient physical activity increased in people aged 60 years and older in all regions and both sexes, but age patterns differed for those younger than 60 years. If 2010–22 trends continue, the global target of a 15% relative reduction between 2010 and 2030 will not be met (posterior probability <0·01); however, two regions, Oceania and sub-Saharan Africa, were on track with considerable uncertainty (posterior probabilities 0·70–0·74). Interpretation Concerted multi-sectoral efforts to reduce insufficient physical activity levels are needed to meet the 2030 target. Physical activity promotion should not exacerbate sex, age, or geographical inequalities. Funding Ministry of Public Health, Qatar, and World Health Organization. Translations For the Spanish and Portuguese translations of the abstract see Supplementary Materials section.

556 sitasi en Medicine
S2 Open Access 2016
Short Physical Performance Battery and all-cause mortality: systematic review and meta-analysis

R. Pavasini, J. Guralnik, Justin C. Brown et al.

BackgroundThe Short Physical Performance Battery (SPPB) is a well-established tool to assess lower extremity physical performance status. Its predictive ability for all-cause mortality has been sparsely reported, but with conflicting results in different subsets of participants. The aim of this study was to perform a meta-analysis investigating the relationship between SPPB score and all-cause mortality.MethodsArticles were searched in MEDLINE, the Cochrane Library, Google Scholar, and BioMed Central between July and September 2015 and updated in January 2016. Inclusion criteria were observational studies; >50 participants; stratification of population according to SPPB value; data on all-cause mortality; English language publications. Twenty-four articles were selected from available evidence. Data of interest (i.e., clinical characteristics, information after stratification of the sample into four SPPB groups [0–3, 4–6, 7–9, 10–12]) were retrieved from the articles and/or obtained by the study authors. The odds ratio (OR) and/or hazard ratio (HR) was obtained for all-cause mortality according to SPPB category (with SPPB scores 10–12 considered as reference) with adjustment for age, sex, and body mass index.ResultsStandardized data were obtained for 17 studies (n = 16,534, mean age 76 ± 3 years). As compared to SPPB scores 10–12, values of 0–3 (OR 3.25, 95%CI 2.86–3.79), 4–6 (OR 2.14, 95%CI 1.92–2.39), and 7–9 (OR 1.50, 95%CI 1.32–1.71) were each associated with an increased risk of all-cause mortality. The association between poor performance on SPPB and all-cause mortality remained highly consistent independent of follow-up length, subsets of participants, geographic area, and age of the population. Random effects meta-regression showed that OR for all-cause mortality with SPPB values 7–9 was higher in the younger population, diabetics, and men.ConclusionsAn SPPB score lower than 10 is predictive of all-cause mortality. The systematic implementation of the SPPB in clinical practice settings may provide useful prognostic information about the risk of all-cause mortality. Moreover, the SPPB could be used as a surrogate endpoint of all-cause mortality in trials needing to quantify benefit and health improvements of specific treatments or rehabilitation programs.The study protocol was published on PROSPERO (CRD42015024916).

744 sitasi en Medicine
S2 Open Access 2016
Scaling up physical activity interventions worldwide: stepping up to larger and smarter approaches to get people moving.

R. Reis, D. Salvo, D. Ogilvie et al.

The global pandemic of physical inactivity requires a multisectoral, multidisciplinary public-health response. Scaling up interventions that are capable of increasing levels of physical activity in populations across the varying cultural, geographic, social, and economic contexts worldwide is challenging, but feasible. In this paper, we review the factors that could help to achieve this. We use a mixed-methods approach to comprehensively examine these factors, drawing on the best available evidence from both evidence-to-practice and practice-to-evidence methods. Policies to support active living across society are needed, particularly outside the health-care sector, as demonstrated by some of the successful examples of scale up identified in this paper. Researchers, research funders, and practitioners and policymakers in culture, education, health, leisure, planning, and transport, and civil society as a whole, all have a role. We should embrace the challenge of taking action to a higher level, aligning physical activity and health objectives with broader social, environmental, and sustainable development goals.

597 sitasi en Medicine, Political Science
S2 Open Access 2017
The neighbourhood physical environment and active travel in older adults: a systematic review and meta-analysis

E. Cerin, Andrea Nathan, J. Van Cauwenberg et al.

BackgroundPerceived and objectively-assessed aspects of the neighbourhood physical environment have been postulated to be key contributors to regular engagement in active travel (AT) in older adults. We systematically reviewed the literature on neighbourhood physical environmental correlates of AT in older adults and applied a novel meta-analytic approach to statistically quantify the strength of evidence for environment-AT associations.MethodsForty two quantitative studies that estimated associations of aspects of the neighbourhood built environment with AT in older adults (aged ≥ 65 years) and met selection criteria were reviewed and meta-analysed. Findings were analysed according to five AT outcomes (total walking for transport, within-neighbourhood walking for transport, combined walking and cycling for transport, cycling for transport, and all AT outcomes combined) and seven categories of the neighbourhood physical environment (residential density/urbanisation, walkability, street connectivity, access to/availability of services/destinations, pedestrian and cycling infrastructure, aesthetics and cleanliness/order, and safety and traffic).ResultsMost studies examined correlates of total walking for transport. A sufficient amount of evidence of positive associations with total walking for transport was found for residential density/urbanisation, walkability, street connectivity, overall access to destinations/services, land use mix, pedestrian-friendly features and access to several types of destinations. Littering/vandalism/decay was negatively related to total walking for transport. Limited evidence was available on correlates of cycling and combined walking and cycling for transport, while sufficient evidence emerged for a positive association of within-neighbourhood walking with pedestrian-friendly features and availability of benches/sitting facilities. Correlates of all AT combined mirrored those of walking for transport. Positive associations were also observed with food outlets, business/institutional/industrial destinations, availability of street lights, easy access to building entrance and human and motorised traffic volume. Several but inconsistent individual- and environmental-level moderators of associations were identified.ConclusionsResults support strong links between the neighbourhood physical environment and older adults’ AT. Future research should focus on the identification of types and mixes of destinations that support AT in older adults and how these interact with individual characteristics and other environmental factors. Future research should also aim to clarify dose-response relationships through multi-country investigations and data-pooling from diverse geographical regions.

541 sitasi en Geography, Medicine
S2 Open Access 2019
A Survey on Model-Based Distributed Control and Filtering for Industrial Cyber-Physical Systems

Derui Ding, Q. Han, Zidong Wang et al.

Industrial cyber-physical systems (CPSs) are large-scale, geographically dispersed, and life-critical systems, in which lots of sensors and actuators are embedded and networked together to facilitate real-time monitoring and closed-loop control. Their intrinsic features in geographic space and resources put forward to urgent requirements of reliability and scalability for designed filtering or control schemes. This paper presents a review of the state-of-the-art of distributed filtering and control of industrial CPSs described by differential dynamics models. Special attention is paid to sensor networks, manipulators, and power systems. For real-time monitoring, some typical Kalman-based distributed algorithms are summarized and their performances on calculation burden and communication burden, as well as scalability, are discussed in depth. Then, the characteristics of non-Kalman cases are further disclosed in light of constructed filter structures. Furthermore, the latest development is surveyed for distributed cooperative control of mobile manipulators and distributed model predictive control in industrial automation systems. By resorting to droop characteristics, representative distributed control strategies classified by controller structures are systematically summarized for power systems with the requirements of power sharing and voltage and frequency regulation. In addition, distributed security control of industrial CPSs is reviewed when cyber-attacks are taken into consideration. Finally, some challenges are raised to guide the future research.

412 sitasi en Computer Science
DOAJ Open Access 2025
Technical note: General formulation for the distribution problem – prognostic assumed probability density function (PDF) approach based on the maximum-entropy principle and the Liouville equation

J.-I. Yano, V. E. Larson, V. E. Larson et al.

<p>A general formulation for the distribution problem is presented, which is applicable to frequency distributions of subgrid-scale variables and hydrometeor size distributions, as well as to probability distributions characterizing data uncertainties. The general formulation is presented based upon two well-known basic principles: the maximum-entropy principle and the Liouville equation. The maximum-entropy principle defines the most likely general distribution form if necessary constraints are specified. This paper proposes to specify these constraints as the output variables to be used in a host model. Once a general distribution form is defined, the problem of the temporal evolution of the distribution reduces to that of predicting a small number of parameters characterizing it. This paper derives prognostic equations for these parameters from the Liouville equation. The developed formulation, which is applicable to a wide range of atmospheric modeling problems, is specifically applied to the condensation growth of cloud droplets as a demonstration.</p>

Physics, Chemistry
DOAJ Open Access 2024
Optimization framework for eco-hydrological connectivity schemes based on graph theory and waterfront accessibility

Yuping Han, Yao Xu, Runxiang Cao et al.

Study Region: Zhengzhou section of the Jialu River. Study Focus: In this study, the Zhengzhou section of the Jialu River was chosen to construct a watershed river network graph model based on graph theory, and this model could describe water volume distribution at diversion nodes and water balance relationships, which aimed to maximize the ecological landscape area. Considering residential aggregation along riverbanks, a waterfront accessibility matrix was used to derive an optimized water system connectivity scheme based on flow allocation at diversion nodes. New Hydrological Insights for the Region: In the optimized scheme, flow distribution from 5 diversion nodes to downstream river sections ranged from 0.2 to 0.8, resulting in significant changes in the landscape area of 20 river segments. The ecological landscape area under the optimal scenario was 31.06 km2, which was 0.03 km2 more than the worst-case scenario. The water system connectivity allocation remained consistent before and after considering waterfront accessibility, and the optimal weighted landscape area was 12.69 km2 with waterfront accessibility in mind. Considering the accessibility of waterfront areas, the center of gravity of the water system connectivity scheme shad undergone a significant change before and after. The research results could provide theoretical support for the construction of regional ecological civilization.

Physical geography, Geology
DOAJ Open Access 2023
Reproducing computational processes in service-based geo-simulation experiments

Zhiyi Zhu, Min Chen, Lingzhi Sun et al.

Geo-simulation experiments (GSEs) are experiments allowing the simulation and exploration of Earth’s surface (such as hydrological, geomorphological, atmospheric, biological, and social processes and their interactions) with the usage of geo-analysis models (hereafter called ‘models’). Computational processes represent the steps in GSEs where researchers employ these models to analyze data by computer, encompassing a suite of actions carried out by researchers. These processes form the crux of GSEs, as GSEs are ultimately implemented through the execution of computational processes. Recent advancements in computer technology have facilitated sharing models online to promote resource accessibility and environmental dependency rebuilding, the lack of which are two fundamental barriers to reproduction. In particular, the trend of encapsulating models as web services online is gaining traction. While such service-oriented strategies aid in the reproduction of computational processes, they often ignore the association and interaction among researchers’ actions regarding the usage of sequential resources (model-service resources and data resources); documenting these actions can help clarify the exact order and details of resource usage. Inspired by these strategies, this study explores the organization of computational processes, which can be extracted with a collection of action nodes and related logical links (node-link ensembles). The action nodes are the abstraction of the interactions between participant entities and resource elements (i.e., model-service resource elements and data resource elements), while logical links represent the logical relationships between action nodes. In addition, the representation of actions, the formation of documentation, and the reimplementation of documentation are interconnected stages in this approach. Specifically, the accurate representation of actions facilitates the correct performance of these actions; therefore, the operation of actions can be documented in a standard way, which is crucial for the successful reproduction of computational processes based on standardized documentation. A prototype system is designed to demonstrate the feasibility and practicality of the proposed approach. By employing this pragmatic approach, researchers can share their computational processes in a structured and open format, allowing peer scientists to re-execute operations with initial resources and reimplement the initial computational processes of GSEs via the open web.

Physical geography, Environmental sciences
DOAJ Open Access 2021
Variabilités spatiale et temporelle des débits et de la géochimie des cours d'eau cévenols du bassin versant des Gardons (Gard, France) : contribution à l'analyse des basses eaux

Maxime Gillet, Pierre-Alain Ayral, Corinne Le Gal La Salle et al.

The increase in the severity of hydrological droughts in the Mediterranean basin in relation to climate change leads to the need to better understand the origin of the water resource to improve its management. The defined study area, the Cevennes upper watershed of the Gardons, presents quite significant variations in terms of low water flows. This article questions these differences and proposes to explain these variances in flows not by a rainfall difference but by a variation in the contribution of the geological reservoirs present in the different watersheds.The study was conducted mainly during the summers of 2018 and 2019 where flows and geochemistry of surface water and groundwater were monitored in 9 watersheds. The use of mixing model in addition to this geochemical-hydrological coupling allows to quantify the contribution of the different formations and shows strong contrast between them. At low water, two formations, black micaschists and limestone, appear to be essential to sustain the flow: they would feed the streams studied to the extent of 41 and 17 % respectively, while they cover only 13 and 8 % of the considered area. The analysis of the contribution of the respective geological formations allows to explain the observed specific discharge of the rivers in the study area.This information of contribution in low water coupled with the flow allows to identify the most productive reservoirs and could help to prioritize the protection of these in view of the scarcity of the resource that will result from climate change.

Physical geography, Geography (General)
DOAJ Open Access 2020
Exploring Virtual Reality in the Higher Education Classroom: Using VR to Build Knowledge and Understanding

Gareth Young, Sam Stehle, Burcin Walsh et al.

irtual reality (VR), as an informative medium, possesses the potential to engage students with immersive, interactive, and informative experiences. When presented in VR, immersive virtual environments (IVEs) can provide three-dimensional visual simulations that can be used to inform students about concepts in specific contexts that would be near impossible to achieve with more traditional teaching methodologies. It is proposed that existing learning frameworks can benefit from exploring the modalities of interaction that are presently afforded via VR from the experiential perspectives of the students. An evaluation is presented that focused on the appraisal of student experiences of immersive technologies as applied in a higher education context, specifically in the use of VR for the exploration of geomorphology theory by physical geography students. This research supports further development of the immersive learning discipline from three different perspectives. First, an empathy mapping method was applied to visualize student experiences and externalize our observed knowledge of student users for creating a shared understanding of their needs and to aid in lesson planning decision making when using VR in the classroom. Second, student experiences were captured using a technology-focused user experience questionnaire to obtain student attitudes immediately post-task. Finally, to assist teachers with the creation of a student-centered lesson plans that incorporate VR in the classroom, eight heuristic guidelines (focus, provocation, stimulation, collaboration, control, digital life, learner skills, multimodal experience) were developed. It is proposed that these findings can be used to provide support for the use of mixed reality and immersive virtual environments in learning that encompass the challenges faced by students and the interdisciplinary education community at large.

Electronic computers. Computer science
DOAJ Open Access 2020
Geographic information system (GIS)-Based multicriteria analysis of flooding hazard and risk in Ambo Town and its watershed, West shoa zone, oromia regional State, Ethiopia

Gemechu Shale Ogato, Amare Bantider, Ketema Abebe et al.

The purpose of the study was to analyze flooding hazard and risk from Geographic Information Systems (GIS)-based multicriteria perspective in Ambo town and its watershed and proposes strategic measures for sustainable flooding disaster risk management in urban watershed. Land use/land cover, elevation, slope, drainage density, soil, and rainfall were considered as important flooding hazard factors. Analysis of flooding risk was undertaken for Ambo town’s watershed using flooding hazard layer and the two elements at risk, namely human population and land use. Weighted linear combination (WLC) method was used in the process of criteria map aggregation for both flooding hazard and flooding risk. The result of the flooding hazard in the watershed reveals that more proportion of the watershed is high and very high flooding hazard area (60.58%). Moreover, more proportion of the town is high and very high flooding hazard area (66.87%). The result of the flooding risk in the watershed reveals that more proportion of the watershed is high and very high flooding risk area (41.76%). Moreover, half of the town is high and very high flooding risk area (50.09%). An integrated basin wide approach to flood management should be practiced as it is essential to address multiple water related issues at watershed level. Moreover, environmental education should be emphasized to build civic responsibility among the citizens. Keywords: Flooding, Hazard, Land use management, Risk, Spatial planning

Physical geography, Geology
DOAJ Open Access 2020
MAQUETE DO PATRIMÔNIO GEOLÓGICO DO MACIÇO ALCALINO DE POÇOS DE CALDAS, DIVISA SP/MG

Vinícius Arcanjo Monteiro

A maquete do maciço alcalino de Poços de Caldas começa com a base cartográfica clássica de Ellert, Björnberg e Coutinho (1959), que trata nesta cartografia com o tema: a geologia do maciço alcalino de Poços de Caldas. A base cartográfica geológica contém litologias e principais riquezas minerais além de abordar conceitos e temas do maciço em questão. Temas irrigados, como mecanismo de intrusão alcalina, principais litologias e localização das amostras coletadas, que são categorias cartográficas. Aliado a esta cartografia base foram consultados alguns artigos que exploram a construção de maquetes, mas por se tratar de um assunto que não possui muitas obras de referência, tornou-se necessário o estudo deste assunto. Primeiramente, foi realizada uma retrospectiva dos principais trabalhos cartográficos sobre o tema sinalizando assim avanços e rupturas na literatura, destacando os principais métodos, técnicas e conceitos empregados a cada momento. Isso serviu, entre outros, para correlacionar os avanços técnicos com os tipos de métodos usados ​​em pesquisas na região; relacionar o contexto social e histórico com as técnicas e métodos empregados pelos cartógrafos em cada época. E também definir nessa a escala de trabalho na construção de nossos resultados. Posteriormente, foram realizados trabalhos de campo, abordando questões relacionadas ao tema. Pretende-se construir com essas análises correlações entre teoria e prática, além de discutir as maquetes no ensino das geociências. Por fim, foi feita uma análise conclusiva sobre a maquete, sob o enfoque da geomorfologia, ou seja, a aplicabilidade das maquetes para uma compreensão do relevo através de estudos de relações da geologia com a natureza e comportamento geomorfológico, seus processos e marcos cartográficos.

Physical geography, Geography (General)
DOAJ Open Access 2019
Towards Comprehensive Observing and Modeling Systems for Monitoring and Predicting Regional to Coastal Sea Level

Rui M. Ponte, Mark Carson, Mauro Cirano et al.

A major challenge for managing impacts and implementing effective mitigation measures and adaptation strategies for coastal zones affected by future sea level (SL) rise is our limited capacity to predict SL change at the coast on relevant spatial and temporal scales. Predicting coastal SL requires the ability to monitor and simulate a multitude of physical processes affecting SL, from local effects of wind waves and river runoff to remote influences of the large-scale ocean circulation on the coast. Here we assess our current understanding of the causes of coastal SL variability on monthly to multi-decadal timescales, including geodetic, oceanographic and atmospheric aspects of the problem, and review available observing systems informing on coastal SL. We also review the ability of existing models and data assimilation systems to estimate coastal SL variations and of atmosphere-ocean global coupled models and related regional downscaling efforts to project future SL changes. We discuss (1) observational gaps and uncertainties, and priorities for the development of an optimal and integrated coastal SL observing system, (2) strategies for advancing model capabilities in forecasting short-term processes and projecting long-term changes affecting coastal SL, and (3) possible future developments of sea level services enabling better connection of scientists and user communities and facilitating assessment and decision making for adaptation to future coastal SL change.

Science, General. Including nature conservation, geographical distribution
DOAJ Open Access 2019
Testing the Effect of Mountain Ranges as a Physical Barrier to Current Gene Flow and Environmentally Dependent Adaptive Divergence in Cunninghamia konishii (Cupressaceae)

Yi-Shao Li, Kai-Ming Shih, Chung-Te Chang et al.

Populations can be genetically isolated by differences in their ecology or environment that hampered efficient migration, or they may be isolated solely by geographic distance. Moreover, mountain ranges across a species’ distribution area might have acted as barriers to gene flow. Genetic variation was quantified using amplified fragment length polymorphism (AFLP) and 13 selective amplification primer combinations used generated a total of 482 fragments. Here, we tested the barrier effects of mountains on gene flow and environmentally dependent local adaptation of Cunninghamia konishii occur in Taiwan. A pattern of genetic isolation by distance was not found and variation partitioning revealed that environment explained a relatively larger proportion of genetic variation than geography. The effect of mountains as barriers to genetic exchange, despite low population differentiation indicating a high rate of gene flow, was found within the distribution range of C. konishii. Twelve AFLP loci were identified as potential selective outliers using genome-scan methods (BAYESCAN and DFDIST) and strongly associated with environmental variables using regression approaches (LFMM, Samβada, and rstanarm) demonstrating adaptive divergence underlying local adaptation. Annual mean temperature, annual precipitation, and slope could be the most important environmental factors causally associated with adaptive genetic variation in C. konishii. The study revealed the existence of physical barriers to current gene flow and environmentally dependent adaptive divergence, and a significant proportion of the rate of gene flow may represent a reflection of demographic history.

DOAJ Open Access 2018
Simulation of actual evapotranspiration from agricultural landscapes in the Canadian Prairies

Myra Martel, Aaron Glenn, Henry Wilson et al.

Study region: This study was carried out in southwestern Manitoba, in the prairie region of Canada. Study focus: Mathematical models are routinely used to estimate evapotranspiration (ET) when measurements are lacking. This study was conducted to select the most relevant models for estimating ET in the Canadian Prairies. Eight reference ET models (i.e., Penman-Monteith, Priestley-Taylor, Makkink, Turc, Maulé et al., Blaney-Criddle, Hargreaves-Samani, and Hamon models) were evaluated. This study also assessed the applicability and transferability of the growing degree day (GDD)-based crop coefficients for estimating crop ET in the Canadian Prairies. New hydrological insights: The equation developed by Maulé et al. (2006) was found to be the best reference ET alternative to the Penman-Monteith equation with a mean relative error of 11%. However, when models were validated against measured crop ET, the simpler radiation-based Turc and Makkink models were found to be the most useful models with daily mean relative errors ranging from 16% to 49%, outperforming the widely accepted Penman-Monteith model. Discrepancies in the GDD-based crop coefficients were found to also contribute to errors; however, results show the potential transferability of GDD-based coefficients across different locations and climatic conditions.

Physical geography, Geology

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