Hasil untuk "Physical geography"

N. Duke, M. Ball, J. Ellison

Numerous factors affect the distribution of mangrove plants. Most mangrove species are typically dispersed by water-buoyant propagules, allowing them to lake advantage of estuarine, coastal and ocean currents both to replenish existing stands and to establish new ones. The direction they travel depends on sea currents and land barriers, but the dispersal distance depends on the time that propagules remain buoyant and viable. This is expected to differ for each species. Similarly, each species will also differ in establishment success and growth development rate, and each has tolerance limits and growth responses which are apparently unique. Such attributes are presumably responsible for the characteristic distributional ranges of each species, as each responds to the environmental, physical and biotic settings they might occupy. In practice, species are often ordered by the interplay of different factors along environmental gradients, and these may conveniently be considered at four geographic scales-global, regional, estuarine and intertidal. We believe these influencing factors act similarly around the world, and to demonstrate this point, we present examples of distributional gradients from the two global biogeographic regions, the Atlantic East Pacific and the Indo-West Pacific.

R P van der Wielen, L.C.P.G.M. de Groot, W. van Staveren et al.

L. H. Lofland

L. Levin, R. Etter, M. Rex et al.

Douglas A. Miller, R. A. White

Valeria Di Fant, Hans Middelkoop, Karianne de Bruin et al.

Abstract Climate adaptation must be intensified globally to keep up with increasing climate change impacts. To date, adaptation is mostly driven by climate risks that need to be reduced and little by opportunities. We identify opportunity windows -i.e. favourable conditions for new or upgraded measures- by constructing an evidence-based dataset from qualitative and quantitative sources, and discuss how they can help to progress adaptation. Here we find evidence of past, present and future adaptation opportunity windows throughout Europe. Present and past triggers for opportunity windows include the implementation of European Union Directives and post-disaster recovery funds, and societal support after floods, droughts and wildfires. Future opportunities relate to aging dams and storm surge barriers. Opportunities also emerge from innovations (e.g. through pilots) which could inform new forms of adaptation. Decision-makers can operationalise and seize adaptation opportunities through adaptive pathways planning, but would need to anticipate opening and closing windows.

N. Owen, E. Cerin, E. Leslie et al.

Bonnie Zhu, A. Joseph, S. Sastry

Ali Matoog Obaid Lebawi, Mahnoosh Moghaddasi, Mehdi Mohammadi Ghaleni et al.

Study region: The Yazd and Ramsar stations are located in hybrid arid and humid climates in Iran, respectively. Study focus: This research study develops a complementary expert system for accurately forecasting reference evapotranspiration (ET0) over one, three, and seven-day horizons by integrating Machine Learning (ML) models with a novel multivariate decomposition technique. Initially, significant input predictor lags were established through cross-correlation, and the War Strategy Optimization (WSO) algorithm was used for optimal Feature Selection (FS) and determining Multivariate Variational Mode Decomposition (OMVMD) parameters. Each predictor was decomposed into Intrinsic Mode Functions (IMFs) to enhance the temporal characteristics of the data. The study introduced the FS-OMVMD-RF, FS-OMVMD-KNNR, and FS-OMVMD-ETE models, utilizing Random Forest (RF), K-Nearest Neighbors Regressor (KNNR), and Extra-Trees Ensemble (ETE) techniques for daily ET0 estimation. These hybrid models were benchmarked against alternatives combining Time-Varying Filter-based Empirical Mode Decomposition (TVF-EMD) with individual models. New hydrological insights for the region: Results demonstrated that the developed models significantly enhance ET0 forecasting capabilities across multiple time scales. Notably, the FS-OMVMD-ETE model achieved the highest accuracy for ET0 (t + 7) at Yazd and Ramsar stations. The analysis indicated that in a hyper-arid climate, the U2 feature has the greatest impact on forecasting, while in a humid climate, Tmean is the most influential factor.

Myroslav Syvyi, Petro Demyanchuk, Igor Kholoshyn et al.

Problem Statement. Analysis of the “Geoinform” archival materials indicates that the reserve of explored raw material deposits for crushed stone and rubble stone in Khmelnytskyi Region (that are suitable for operation based on the magnitude of reserves, environmental conditions, logistical requirements, etc.) is practically exhausted. Exploration work is not being conducted, the capacities of operating mining enterprises are far from fully utilized, and predominantly small-volume deposits are available for development. Therefore, there is an urgent need for a critical analysis of the current state of the raw material base for rubble and crushed stone in the Khmelnytskyi Region. This is especially crucial given that in the post-war period, the demand for increasing their production volumes will sharply rise for restoring housing and destroyed infrastructure. Presentation of the Main Material. The article analyzes the current state of research into deposits of raw materials for crushed stone and rubble production in the Khmelnytskyi Region. It shows the correlation of deposits with specific stratigraphic subdivisions and clarifies the general patterns of placement for various types of building stone deposits across the region. The degree of exploration of building stone deposits and their level of industrial development are analyzed. The territorial density (saturation of the territory) and the provision of explored reserves to the population of territorial units are calculated. The dynamics of raw material extraction in recent years are shown, and proposals for increasing extraction volumes in the region are presented. The areas occupied by active quarries under productive lands, unproductive lands, and forest areas have been identified. It’s concluded that the placement of a significant number of explored raw material reserves in the region on unproductive lands creates favorable prospects for their future development. Analysis of raw material extraction volumes at state and commercial enterprises in the region, the assortment of their products, and the long-terms of provision with reliable reserves allowed us to conclude that overall, the volumes of raw material extraction in the region are satisfactory, even compared to pre-war years. However, there is insufficient provision of reliable reserves for some active quarries, extraction is concentrated in just a few territorial communities, and many enterprises are insufficiently utilized compared to their design capacities. Conclusions. The article establishes patterns in the location of various types of crushed stone and rubble raw materials across the region. Calculations were made for the territorial density of explored reserves, their provision to individual administrative units, and the placement of explored deposits on productive, unproductive, and forest lands. Current volumes of raw material extraction and the provision of reliable reserves for active quarries have been determined, and possibilities for genuinely increasing raw material extraction in the region have been recommended.

Mario A. Arrieta, Ingrid Boasso, Lila Bernardi

La osteocondritis disecante es una rara condición patológica caracterizada por la separación de un fragmento de cartílago articular necrótico del hueso subcondral subyacente. Si bien su etiología sería multifactorial, se la asocia principalmente al estrés mecánico. Desde la paleopatología, su análisis ofrece un gran potencial para explorar los modos de vida de las poblaciones pasadas. El objetivo de este trabajo es analizar la expresión de osteocondritis disecante en 57 individuos esqueléticos procedentes del sitio Rincón Chico 21 (Santa María, Catamarca). Este cementerio constituye un área de entierro utilizada entre los períodos de Desarrollos Regionales y de contacto Hispano-Indígena inicial (ca. 1.200-1.550 AD). Los individuos analizados abarcan los rangos etarios comprendidos entre los adolescentes y adultos medios/mayores y ambos sexos están representados. Se registró la presencia de lesiones en 47 elementos pertenecientes al menos a 20 individuos (35,09% de la muestra). La rodilla (26,32% de los individuos) y la articulación metatarsofalángica (15,79% de los individuos) fueron las más afectadas. Los femeninos y los adultos medios/mayores manifestaron mayores prevalencias. Los resultados sugieren que estas poblaciones habrían estado expuestas a altos niveles de estrés mecánico vinculados con las prácticas culturales asociadas a una economía de subsistencia agropastoril.

L. Håkanson, Björn Ambos

This study investigates the antecedents of psychic distance. Building on original data in 25 of the world's largest economies, we investigate potential drivers of perceived psychic distances to foreign countries. The results show these perceptions to be influenced by a range of cultural, geographic, political and economic factors. Among these, absolute geographic distance accounts for the largest share of the explained variance, suggesting that physical distance should be given a more prominent role when it comes to empirically investigating international business decisions for which psychic distance perceptions may be important. The findings also suggest that, used in isolation, 'cultural distance' - as measured by the so called Kogut and Singh index - is a poor predictor of such perceptions.

Andrea Cucina

Occlusal wear has been present in humans since the beginning of our evolutionary journey. Even considering its intrinsic limitations, its study is central to estimating age at death, making inferences on diet, on the way food was prepared, and on cultural non-masticatory use of teeth. Its study allows us to understand how occlusal wear has responded to the evolutionary changes that characterized human beings from the onset of agriculture up to the more recent Industrial Revolution. This brief review paper focuses on the study of occlusal wear from an anthropological and bioarchaeological perspective. It discusses its importance for understanding past societies, its advantages, and its limitations in anthropological studies of skeletonized individuals, and how different fields of study in odontology, dental anthropology/bioarchaeology focus on occlusal wear from very distinctive and rarely overlapping perspectives, but that can significantly benefit from one another in a multidisciplinary approach.

Руслан Гаврилюк, Олена Шпак, Ольга Логвиненко et al.

Formulation of the problem. As a result of Russian military aggression, a significant number of petroleum product supply objects were destroyed in Ukraine, which led to the formation of new sources of subsurface contamination. Such sources cause significant damage to the environment, the assessment of which is one of the key priorities among the entire range of environmental impacts of Russian aggression. The first stage is the assessment of the state of the environment, which includes the determination of objects, nature, scale and features of subsurface contamination. Its results serve as the basis for further stages of damage assessment: development of a monitoring network and restoration measures, the total costs of which should form the basis for a monetary assessment of the damage. The purpose of the article is to develop a methodology for the environmental and geological survey of petroleum contamination sources taking into account the consequences of the destruction of petroleum product supply facilities as a result of military operations. The scope of the ecological and geological survey of the petroleum contamination sources is determined by the purpose of its implementation, the size of a survey area and adjacent territories under the influence of contamination, the necessary accuracy of forecasting contamination spreading, and determining the risk to humans and the environment. Main Results. This article describes the methodological aspects of the environmental and geological survey of the sources of subsurface contamination with petroleum products, developed on the basis of our long-term scientific research. The general principles of conducting the ecological and geological survey are described, and the scope and structure of research are proposed at all stages of the ecological and geological survey of petroleum contamination sources: search, exploration and exploration during remedial actions. Three classes of ecological danger of petroleum contamination sources are distinguished. The 1st class refers to contaminated areas where the threat of an above-standard content of petroleum products already exists or it is expected in the next 10 years, which requires urgent remedial actions, including the localization and/or elimination of petroleum contamination sources. The 2nd class of danger refers to territories where the threat of exceeding the regulatory level of petroleum products and the task of economic or social damage is expected after 10 years, and first of all, it is necessary to carry out works on the localization and/or elimination of contamination sources and regular observations. The 3rd danger class includes territories where petrole- um contamination does not pose a significant danger but such a threat may arise when conditions change. In this case, it is recommended to observe the development of petroleum contamination. The cases of environmental and geological surveys conducted in the area of the international airport "Boryspil" and Bila Tserkva town, which are potentially comparable to the sources formed as a result of military aggression of the Russian Federation in terms of the scale of contamination, are considered. Conclusions. The developed principles of ecological and geological survey of the sources of subsurface contamination with petroleum products can be used at many petroleum product supply facilities that were destroyed as a result of Russian military aggression.

A. L. L. Dauner, A. L. L. Dauner, F. Schenk et al.

<p>Sea ice is crucial in regulating the heat balance between the ocean and atmosphere and quintessential for supporting the prevailing Arctic food web. Due to limited and often local data availability back in time, the sensitivity of sea-ice proxies to long-term climate changes is not well constrained, which renders any comparison with palaeoclimate model simulations difficult. Here we compiled a set of marine sea-ice proxy records with a relatively high temporal resolution of at least 100 years, covering the Common Era (past 2k years) in the Greenland–North Atlantic sector of the Arctic to explore the presence of coherent long-term trends and common low-frequency variability, and we compared those data with transient climate model simulations. We used cluster analysis and empirical orthogonal functions to extract leading modes of sea-ice variability, which efficiently filtered out local variations and improved comparison between proxy records and model simulations. We find that a compilation of multiple proxy-based sea-ice reconstructions accurately reflects general long-term changes in sea-ice history, consistent with simulations from two transient climate models. Although sea-ice proxies have varying mechanistic relationships to sea-ice cover, typically differing in habitat or seasonal representation, the long-term trend recorded by proxy-based reconstructions showed a good agreement with summer minimum sea-ice area from the model simulations. The short-term variability was not as coherent between proxy-based reconstructions and model simulations. The leading mode of simulated sea ice associated with the multidecadal to centennial timescale presented a relatively low explained variance and might be explained by changes in solar radiation and/or inflow of warm Atlantic waters to the Arctic Ocean. Short variations in proxy-based reconstructions, however, are mainly associated with local factors and the ecological nature of the proxies. Therefore, a regional or large-scale view of sea-ice trends necessitates multiple spatially spread sea-ice proxy-based reconstructions, avoiding confusion between long-term regional trends and short-term local variability. Local-scale sea-ice studies, in turn, benefit from reconstructions from well-understood individual research sites.</p>

Celeste Winston

This article synthesizes contributions of a growing body of geographic scholarship on marronage and presents a framework of maroon geographies to guide scholarship and political organizing centered on Black place- making and racial justice. I situate marronage-focused geographic scholarship within Black geographies literature that highlights the reverberations of transatlantic slavery in our current world order and historical and ongoing Black spatial acts of struggle and survival. Based on this scholarship and my own empirical research in Montgomery County, Maryland, I construct a framework of maroon geographies that encompasses physical sites of past flight from slavery as well as spaces produced through contemporary Black struggles. This framework comprises four main features: reworking geographic refuse, Black cooperative place- making, fugitive infrastructure, and a spatial strategy of entanglement. Maroon geographies offer a framework to explicitly address legacies of Black spatial epistemologies and practices that made possible freedom from slavery and that continue to shape sites of radical transformation and possibility. I conclude with a discussion of how the framework can inform scholarship and Black organizing.

GABRIELA SOBRAL

Prolacerta broomi is one of the most important of fossil reptiles. First considered as one of the earliest members of squamates, this basal archosauromorph has been used as a model for diapsid morphological evolution ever since its discovery, playing a pivotal role in hypotheses on the origin of diapsid reptiles. The holotype of Prolacerta broomi (UCMZ 2003.41R) is known from a mostly complete skull, but the original description is limited to the superficial features of the skull roof and palate. Since then, many other specimens of Prolacerta broomi have been recovered that potentially account for this limited access to anatomical information, but it remains unclear whether these aspects correspond well to the known material of the holotype. Here, the skull morphology of the holotype of Prolacerta broomi is revisited through the use of µCT scans. The identifications of some cranial elements have been corrected, such as the left prefrontal and lacrimal, and several new elements are revealed, including the epi- and ectopterygoids, prearticular, coronoid, and braincase bones. The orbitonasal region is described in detail and significantly shows a contribution of the lacrimal to the dorsal alveolar canal. Finally, the addition of the holotype as an independent OTU in recently published analyses indicate conflicts with the current knowledge on Prolacerta broomi phylogenetic affinity and taxonomy. First, it points to potential taxonomic inconsistency since the holotype does not form a monophyletic group with other Prolacerta broomi OTUs in any of the analyses and, second, it suggests a more basal position for the holotype than that recovered in some studies, more basal than rhynchosaurs and close to the origin of Crocopoda. Together, these findings indicate areas of future research interest in the study of early evolving archosauromorphs.

K. Armour, C. Bitz, G. Roe

Patricia L. M. Lee, M. Dawson, S. Neill et al.

W. Pearce, K. Holmberg, I. Hellsten et al.

In September 2013 the Intergovernmental Panel on Climate Change published its Working Group 1 report, the first comprehensive assessment of physical climate science in six years, constituting a critical event in the societal debate about climate change. This paper analyses the nature of this debate in one public forum: Twitter. Using statistical methods, tweets were analyzed to discover the hashtags used when people tweeted about the IPCC report, and how Twitter users formed communities around their conversational connections. In short, the paper presents the topics and tweeters at this particular moment in the climate debate. The most used hashtags related to themes of science, geographical location and social issues connected to climate change. Particularly noteworthy were tweets connected to Australian politics, US politics, geoengineering and fracking. Three communities of Twitter users were identified. Researcher coding of Twitter users showed how these varied according to geographical location and whether users were supportive, unsupportive or neutral in their tweets about the IPCC. Overall, users were most likely to converse with users holding similar views. However, qualitative analysis suggested the emergence of a community of Twitter users, predominantly based in the UK, where greater interaction between contrasting views took place. This analysis also illustrated the presence of a campaign by the non-governmental organization Avaaz, aimed at increasing media coverage of the IPCC report.