Unraveling the relative importance of ecological processes regulating microbial community structure is a central goal in microbial ecology. Here, we used high-throughput sequencing to examine the ...relative contribution of selective and neutral processes in the assembly of abundant and rare subcommunities from three subtropical bays of China. We found that abundant and rare bacterial taxa were distinctly different in diversity, despite the similar biogeographic patterns and strong distance-decay relationships, but the dispersal of rare bacterial taxa was more limited than that of abundant taxa. Furthermore, the environmental (selective processes) and spatial (neutral processes) factors seemed to govern the assembly and biogeography of abundant and rare bacterial subcommunities, although both factors explained only a small fraction of variation within the rare subcommunity. More importantly, variation partitioning (based on adjusted R
in redundancy analysis) showed that spatial factors exhibited a slightly greater influence on both abundant and rare subcommunities compared to environmental selection; however, the abundant subcommunity had a much stronger response to spatial factors (17.3% of pure variance was explained) than that shown by the rare bacteria (3.5%). These results demonstrate that environmental selection and neutral processes explained the similar biogeographic patterns of abundant and rare subcommunities, but a large proportion of unexplained variation in the rare taxa (91.1%) implies that more complex assembly mechanisms may exist to shape the rare bacterial assemblages in the three subtropical bays.
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Assembling a collection of very prominent researchers in the field, the Handbook of Spatial Statistics presents a comprehensive treatment of both classical and state-of-the-art aspects of this ...maturing area. It takes a unified, integrated approach to the material, providing cross-references among chapters.The handbook begins with a historical intro
Spatial database of morphometric features based on basin approach is developed for Krasnoyarsk region. The water basins are ranged into four levels. The digital model of hydrography network developed ...by VSEGEI was used, in combination to Whitebox GAT, QGIS and ArcGIS software. The average climate features are calculated due to this digital model, and spatial analysis supported with advanced non-linear statistics is provided.
Mutualistic plant-pollinator interactions play a key role in biodiversity conservation and ecosystem functioning. In a community, the combination of these interactions can generate emergent ...properties, e.g., robustness and resilience to disturbances such as fluctuations in populations and extinctions. Given that these systems are hierarchical and complex, environmental changes must have multiple levels of influence. In addition, changes in habitat quality and in the landscape structure are important threats to plants, pollinators and their interactions. However, despite the importance of these phenomena for the understanding of biological systems, as well as for conservation and management strategies, few studies have empirically evaluated these effects at the network level. Therefore, the objective of this study was to investigate the influence of local conditions and landscape structure at multiple scales on the characteristics of plant-pollinator networks. This study was conducted in agri-natural lands in Chapada Diamantina, Bahia, Brazil. Pollinators were collected in 27 sampling units distributed orthogonally along a gradient of proportion of agriculture and landscape diversity. The Akaike information criterion was used to select models that best fit the metrics for network characteristics, comparing four hypotheses represented by a set of a priori candidate models with specific combinations of the proportion of agriculture, the average shape of the landscape elements, the diversity of the landscape and the structure of local vegetation. The results indicate that a reduction of habitat quality and landscape heterogeneity can cause species loss and decrease of networks nestedness. These structural changes can reduce robustness and resilience of plant-pollinator networks what compromises the reproductive success of plants, the maintenance of biodiversity and the pollination service stability. We also discuss the possible explanations for these relationships and the implications for landscape planning in agricultural areas.
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Food accessibility has been a subject of growing interest due to its impact on public health outcomes. This paper describes a spatial analysis method to identify gaps in geographic food access and ...correlate them with a variety of demographic and socioeconomic factors. The proposed food accessibility metric is the square footage of supermarkets that can be reached within 10 min travel time by walking, biking, driving, and 30 min travel time by walk/transit. The spatial analysis is conducted for the centroids of each census tract within a study area, and the approach is illustrated with an application for the state of Massachusetts. Correlations between demographic and socioeconomic explanatory variables and food accessibility are explored using the Gradient Boosted machine learning model. More specifically, the explanatory variables are percent minority population, percent of population in poverty, vehicle ownership, and population density. The spatial analysis shows a strong correlation between food accessibility and population density. The machine learning model is then used to identify gaps in food accessibility for each transportation mode while controlling for community characteristics. The residuals of the model reveal which communities have the lowest food accessibility relative to other similar communities within the state. This research provides a quantitative method to identify communities that have reduced access to food relative to state-wide trends. Lastly, it provides insights for where policy interventions would be valuable for improving food access in addition to recommendations on increasing food accessibility.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Urban areas consume more than 66% of the world's energy and generate more than 70% of global greenhouse gas (GHG) emissions. With the world's population expected to reach 10 billion by 2100, and with ...nearly 90% of people living in urban areas, a critical question for planetary sustainability is how the size of cities affects energy use and carbon dioxide (CO2) emissions. Are urban agglomerations more energy and emission efficient than smaller cities? Does urban agglomeration exhibit gains from economies of scale concerning emissions? Here, we examine the relationship between urban agglomeration and CO2 emissions for urban agglomeration in the Yangtze River Delta in China using a STIRPAT (Stochastic Impacts by Regression on Population, Affluence and Technology) model considering the spatial effects. Also, it examines the influence of economic development, industrial structure, opening-up level, and technology progress on carbon emissions by exploring the spatial agglomeration and spillover effects. Our major finding is that urban size has a negative correlation to carbon emissions, demonstrating that urban agglomeration is more emission efficient. In addition, our results showed that carbon emission driving factors, such as technology progress, opening-up, and population, have spatial dependence and spatial spillover effects. It means a city's carbon emissions are not only influenced by its own factors but also have an impact on neighboring cities. Therefore, cross-city or urban agglomeration policy, and actions of reducing carbon emissions, are necessary, whilst also developing a low-carbon economy by increasing the proportion of high-tech industry through technological progress and developing vigorous resource-saving and an environmentally friendly tertiary industry.
•Urban agglomeration is more emissions efficient.•Time-series carbon inventories for 25 cities Yangtze River Delta are constructed during 2005–2016.•Cities are highly integrated within an urban agglomeration.•There is spatial spillover effects on other regions' CO2 emission.
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Considerable attention has recently been given to the study of simultaneous energy harvesting and vibration attenuation in metastructures. However, only linear metastructures were investigated ...although nonlinear metastructures and nonlinear electromechanical devices offer superior interesting wave propagation phenomena (e.g., birth of solitary waves, tunable bandgap, acoustic nonreciprocity) and broadband energy harvesting. In this paper, we investigate the wave propagation in a weakly nonlinear metastructure with electromechanical resonators. Explicit expressions are derived for the nonlinear dispersion relations using the method of multiple scales. These expressions are validated via direct numerical integration. We carried out parametric studies to investigate the role of different parameters of the electromechanical resonators on the linear and nonlinear band structure. To obtain further detailed information on the nonlinear wave propagation, we employ spectro-spatial analysis on the numerical simulations. This spectro-spatial analysis can reveal the output voltage distortion due to different types of nonlinearities. The results indicate that nonlinear chain can enhance energy harvesting through the birth of solitary wave and without degrading the boundary of the bandgap. The results also suggest that such a system is suitable for designing electromechanical diodes and rectifiers.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
İşlevsel, teknik ve estetik bakımdan nitelikli yapay çevre üretimi hedefi ile üst düzey işgücü, zaman ve bütçe ayrılarak düzenlenen ulusal mimari proje yarışmalarında; büyük ölçekli beklenti ve ...kaynakların aksine mekânsal/biçimsel kullanım sorunları açığa çıkabilmektedir. Teori–pratik uyuşmazlıklarını yansıtan kullanıcı–mekan ilişkisinin sonuçları; hukuk, maliyet, ideoloji, alt süreç işletimi vb. etkenler dizgesi içerisinde bir problem diliminin mevcudiyetine işaret etmektedir. Araştırma; ulusal mimari proje yarışmaları sonuç ürünlerinde karşılaşılan mekânsal ve biçimsel sorunların alt süreçler ile olan ilişkilerine odaklanmaktadır. Bu ilişki ağının çözümlenmesi; üç boyutlu mekan, donatı ve ekipmanlarda kullanıcı gereksinmelerinin karşılanabilme kapasitesinin tespitinin ve yarışma alt süreçlerine girdi olarak aktarılan öznel/nesnel yapılı verilerin analizinin senkronize biçimde gerçekleştirilmesini gerekli kılmaktadır. Bu bağlamda; ulusal mimari proje yarışmaları sonucunda hizmete sunulan Bağ-Kur Genel Müdürlük Sitesi ve Türk Eczacıları Birliği Sosyal ve Kültürel Tesisleri; kullanım sürecinde değerlendirilmiş, diğer yandan yarışma alt süreçlerine ilişkin veriler elde edilmiştir. Değerlendirme çalışmalarının sonuçları ve alt süreç dokümanları, birlikte ele alınarak etüt edilmiştir. Araştırma sonucunda; i) Her iki yapay çevrenin kullanıcı müdahaleleri, mekânsal sorunlar ve kapasite problemleri barındırdığı belirlenmiştir. ii) Bunların önemli bir bölümünün yarışma alt süreçlerinde nesnel girdilerin eksikliğine dayalı olarak meydana geldikleri belgelenmiştir. iii) Yarışmalara ileri besleme sağlayabilecek öneriler sunulmuştur.
Google Earth Engine is a cloud-based platform for planetary-scale geospatial analysis that brings Google's massive computational capabilities to bear on a variety of high-impact societal issues ...including deforestation, drought, disaster, disease, food security, water management, climate monitoring and environmental protection. It is unique in the field as an integrated platform designed to empower not only traditional remote sensing scientists, but also a much wider audience that lacks the technical capacity needed to utilize traditional supercomputers or large-scale commodity cloud computing resources.
•Large-scale computing is ubiquitously available but requires expertise to use.•Earth Engine is a platform designed to make planetary-scale RS analysis easy.•A large catalog co-located with massive CPU allows for interactive data exploration.•Its speed and ease of use are accelerating scientific discovery.•Some processes, like recursion, are currently ill-suited for this architecture.
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