Although urbanization can lead to habitat loss and biodiversity decline, it has also helped certain declining species recover by providing resources such as food or shelter. Chimney Swifts (Chaetura ...pelagica) are migratory aerial insectivores that adapted to use masonry chimneys as nesting and communal roosting sites after European colonization and subsequent widespread forest loss. These structures are now becoming obsolete and are being removed or capped, which again threatens the habitat availability for this declining species. In this study, we describe the autumn roosting dynamics of a system of urban roost sites in Asheville, North Carolina, USA, a fast-growing mid-sized city situated in the central Atlantic migratory flyway. Using historical community science records, we first compiled a list of chimneys within city limits that were known to be used as communal roosting sites during the autumn roosting season. We measured physical and environmental characteristics of these chimneys and related them to current and historical patterns of roost use. We found that a combination of chimney height and limited tree canopy cover within 50 m of the chimney explained much of the variation in maximum roost size. In the autumn of 2020, we surveyed most of these sites, many of them several times throughout the season, to understand site-specific use, timing, and roost size during the migration season. Roost sites were used sequentially rather than concurrently throughout the migration season: some roosts formed and dissipated early in the study period, other roosts did not form until later in the season and were larger than the earlier roosts, and some were occupied continuously until the last swifts departed the study area. Our study shows that (1) post-breeding and migratory swifts may choose communal roost sites based on certain characteristics, and (2) these roost sites may serve different roles for different populations of swifts during the autumn migration season, which has conservation implications for this declining species. Received 3 August 2021. Accepted 26 February 2022.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Based on the literature sample data of the research topics related to urbanization and ecological environment relationship in the Yellow River Basin in CNKI database from 2000 to 2022, this paper ...uses excle and CiteSpace software to systematically sort out the preface, current hot spots and development trends of the research on the relationship between urbanization and ecological environment in the Yellow River Basin through volume analysis, keyword co-occurrence and cluster analysis, and the results show that the existing research scale tends to be smaller, and pays attention to multi-scale analysis and comparison. Comparing research from a large to a small scale is easier to solve practical problems; Secondly, it shows the cross-combination of measurement methods, and some studies pay attention to the cross-combination of mathematical models and spatial measurement methods in coupling measurement methods. Finally, the research content shifted from qualitative status analysis and static evaluation to quantitative analysis and dynamic trend evaluation.
Qingdao is a city located along the eastern province of Shandong, specifically along the east cost of the Republic of China, establishing the reasons why it is considered as one of the largest ...metropolitan cities within the province. Urbanization of the city is widely considered as one of the inevitable tendencies driven towards accompanying the process of modernization and industrialization of the human society. This research study sought to examine the Impact of urban sprawl on carbon emission in Qingdao-Shandong Province. According to the findings, urban sprawl is considered as an irreversible global aspect, with some of its fundamental characteristics hedged on the increase of populations in major urban centers, the increased densities and expansion of the spatial sizes of cities, and a rampant changes in the manner in which land and buildings are used; all these managed through the inclusion of planning schemes and strategies. Qingdao-Shandong Province is in this case expected to experience a rise in the demand for travel that will see an increase of over 4.7 million people and trips on a daily basis from the 9.4 million thresholds in 2020.
L’urbanisation de Douala s’est heurtée depuis sa création aux revendications foncières des peuples autochtones. Premier facteur de production permettant l’entretien des hommes, la terre dans la ...conception autochtone, est un dépôt d’énergie, un réservoir des forces mises à la disposition des êtres humains, qui pour en tirer profit, doivent les maîtriser dans leurs activités. C’est un bien commun, terre des ancêtres dont chaque unité lignagère dans le cadre de la jouissance d’un droit absolu bénéficie d’une parcelle. Confrontée à la logique mercantile et à la notion de propriété privée issue du droit moderne, la terre à Douala devient objet d’affrontement entre autochtones, allogènes et pouvoirs publics, contribuant à influencer considérablement l’urbanisation de la ville de sa création à nos jours. La création des identités locales artificielles par les découpages territoriaux récents ne semble pas arrêter ce phénomène dans l’action publique urbaine contemporaine.
Using the case of the village of Villeray, on the Island of Montreal, this research note will try to demonstrate that the conventional sale of vacant lots, duly documented in registry offices, is not ...the only form of access to property. Another strategy, just as legal, but unnoticed by historians, was commonly used. It remains difficult to document because it rests on private understandings taking the form of contracts, sale commitments, that defines the terms of sale of said lot. Ubiquitous in Villeray, these contracts allow for payments of varying length, going up to a decade. Often, they were transferred to a third party by the original buyer to avoid losing the payments made up to then. If it allowed people of modest means to own property, this particular strategy was also quite profitable for land developer, accelerating the sale of vacant lots and allowing them to avoid land taxes, paid by the prospective buyers as part of the sale commitment.
Kentleşme sadece kırsal alanlardan kentsel alanlara doǧru göç eden bir nüfus hareketinden ibaret olmayıp, toplumun ekonomik ve doǧal yapısındaki deǧişimlerden de kaynaklanmaktadır. Bu baǧlamda ...kentleşme düzeyinin belirlenmesi için demografik faktörlerin yanı sıra ekonomik ve sosyal faktörlerin de irdelenmesi gerekmektedir. Bu çalışmanın amacı, TR 81 Bölgesindeki Düzey 2 iller kategorisinde yer alan Zonguldak, Bartın ve Karabük illerinin kentleşme oranları ve kentleşme düzeylerini belirlemektir. Bu amaç doǧrultusunda veri toplama aracı olarak TR81 Düzey 2 bölgesine ilişkin BAKKA (Batı Karadeniz Kalkınma Ajansı) tarafından hazırlanmış raporlar, İŞKUR (Türkiye İş Kurumu) raporları, TÜİK (Türkiye İstatistik Kurumu) veri tabanı ve bölge için hazırlanmış kurum ve kuruluşların araştırma raporları kullanılmıştır. Çalışma sonunda Zonguldak, Bartın ve Karabük illeri karşılaştırılarak deǧerlendirilmiştir. TR81 Bölgesi illerinin kentleşme oranlarının ve kentleşme düzeylerinin saptanması bölgeye yönelik planlama çalışmaları açısından önem taşımaktadır.
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