scholarly journals City Trees and Municipal Wi-Fi Networks: Compatibility or Conflict?

2009 ◽  
Vol 35 (4) ◽  
pp. 203-210
Author(s):  
Igor Lacan ◽  
Joe McBride
Keyword(s):  
Computer Network ◽  
Urban Forestry ◽  
Urban Infrastructure ◽  
Leaf Size ◽  
Access Point ◽  
Urban Trees ◽  
Signal Attenuation ◽  
Leaf Size And Shape ◽  
Canopy Depth ◽  
The City

Conflict between city trees and infrastructure remains a problem in urban forestry. Municipal Wi-Fi, a citywide wireless computer network, may become a part of urban infrastructure, and because trees can diminish Wi-Fi signals, potential exists for conflict between urban trees and municipal Wi-Fi. This study examines attenuation of Wi-Fi signals in the City of Mountain View, California, U.S. by positioning a wireless-equipped computer so that trees obstructed the line-of-sight (LOS) between the computer and a Wi-Fi access point. Signal attenuation ranged from < 2 dB to 19 dB (mean: 5.6 dB), depending on the number and types of trees present. Although trees significantly attenuated signals, they did not diminish the average signal strength below -75 dBm (the minimum for a Wi-Fi connection) in any of the tests. A general linear model (r2 = 0.55) indicated that some tree characteristics (tree size, canopy depth, leaf type), but not others (number of trees in LOS, presence of leaves, leaf size, and shape) helped explain variation in signal attenuation. As long as the effect of urban trees is taken into account during planning of Wi-Fi networks, trees should not interfere with municipal Wi-Fi operation.

scholarly journals Vulnerability of Austin’s urban forest and natural areas: A report from the Urban Forestry Climate Change Response Framework

2020 ◽  
Author(s):  
Leslie A. Brandt ◽  
Cait Rottler ◽  
Wendy S. Gordon ◽  
Stacey L. Clark ◽  
Lisa O'Donnell ◽  
...  
Keyword(s):  
Habitat Suitability ◽  
Native Species ◽  
Urban Forest ◽  
Urban Forestry ◽  
Urban Trees ◽  
Suitable Habitat ◽  
Climate Trends ◽  
Natural Areas ◽  
Species Vulnerability ◽  
The City

The trees, developed green spaces, and natural areas within the City of Austin’s 400,882 acres will face direct and indirect impacts from a changing climate over the 21st century. This assessment evaluates the vulnerability of urban trees and natural and developed landscapes within the City Austin to a range of future climates. We synthesized and summarized information on the contemporary landscape, provided information on past climate trends, and illustrated a range of projected future climates. We used this information to inform models of habitat suitability for trees native to the area. Projected shifts in plant hardiness and heat zones were used to understand how less common native species, nonnative species, and cultivars may tolerate future conditions. We also assessed the adaptability of planted and naturally occurring trees to stressors that may not be accounted for in habitat suitability models such as drought, flooding, wind damage, and air pollution. The summary of the contemporary landscape identifies major stressors currently threatening trees and forests in Austin. Major current threats to the region’s urban forest include invasive species, pests and disease, and development. Austin has been warming at a rate of about 0.4°F per decade since measurements began in 1938 and temperature is expected to increase by 5 to 10°F by the end of this century compared to the most recent 30-year average. Both increases in heavy rain events and severe droughts are projected for the future, and the overall balance of precipitation and temperature may shift Austin’s climate to be more similar to the arid Southwest. Species distribution modeling of native trees suggests that suitable habitat may decrease for 14 primarily northern species, and increase for four more southern species. An analysis of tree species vulnerability that combines model projections, shifts in hardiness and heat zones, and adaptive capacity showed that only 3% of the trees estimated to be present in Austin based on the most recent Urban FIA estimate were considered to have low vulnerability in developed areas. Using a panel of local experts, we also assessed the vulnerability of developed and natural areas. All areas were rated as having moderate to moderate-high vulnerability, but the underlying factors driving that vulnerability differed by natural community and between East and West Austin. These projected changes in climate and their associated impacts and vulnerabilities will have important implications for urban forest management, including the planting and maintenance of street and park trees, management of natural areas, and long-term planning.

The impact of leaf shape on the feeding preference of insect herbivores: experimental and field studies with Capsella and Phyllotreta

1996 ◽  
Vol 351 (1348) ◽  
pp. 1671-1677 ◽  
Keyword(s):  
Leaf Shape ◽  
Laboratory Data ◽  
Leaf Size ◽  
Field Studies ◽  
Feeding Preference ◽  
Insect Herbivores ◽  
Flea Beetles ◽  
Shape Effects ◽  
Leaf Size And Shape ◽  
The Impact

Leaves display an enormous array of sizes and shapes. Although these attributes appear to have evolved primarily in response to abiotic conditions in the plant’s habitat, the importance of insect herbivores as additional selective agents is still poorly understood. A necessary requirem ent for leaf size and shape to evolve in response to attack by insects is that insects must respond to and/or be affected by, leaf morphology. We tested leaf-shape preferences in adult flea beetles ( Phyllotreta spp.) feeding on the highly variable rosette leaves of Capsella bursa-pastoris . Contrary to theoretical expectation (Brown & Lawton 1991), leaves with deeply lobed margins were more intensely damaged, both in field-collected and experimental plants. In two ancillary experiments with Capsella , we found that Spodoptera caterpillars showed no preferences for leaf shape, but that adult vine weevils ( Otiorhynchus sulcatus ) did, preferring (as predicted), undivided over divided leaves. We conclude that Brown & Law ton’s (1991) hypothesis is at best weakly supported by laboratory data for vine weevils, refuted by laboratory data for Spodoptera , and consistently refuted by both laboratory and field data for flea beetles. Although the experiment tried to reduce confounding variables to a minimum, interpretation was complicated by correlations between leaf shape and other developmental parameters of the plants, and highlights the difficulty of disentangling leaf-shape effects from other confounding factors.

Favelas, Affordable Housing, and Authoritarian Urbanism in the Era of Mass Eradication in Rio de Janeiro, 1960s–1970s

2021 ◽  
Author(s):  
Leandro Benmergui
Keyword(s):  
Affordable Housing ◽  
Low Income ◽  
Rio De Janeiro ◽  
Social Science Research ◽  
Urban Infrastructure ◽  
Science Research ◽  
Military Regimes ◽  
The 1960S ◽  
The Right ◽  
The City

As the number of favelas and poor residents of Rio de Janeiro grew quickly by the mid-20th century, they became the object of policymaking, social science research, real estate speculation, and grassroots mobilization. After a decade in which local authorities recognized the de facto presence of favelas but without legally ascertaining the right of permanence, the 1960s and early 1970s witnessed the era of mass eradication. Seemingly contradictory—but complementary—policies also included the development of massive low-income housing complexes and innovative community development and favela urbanization experiences empowered by community organizations with the assistance of experts committed to improving the lives of poor Cariocas (residents of Rio). Favelas in Rio were at the crossroads of a particular interplay of forces: the urgent need to modernize Rio’s obsolete and inadequate urban infrastructure; the new administrative status of the city after the inauguration of Brasilia; and the redefinition of the balance of power between local, municipal, and federal forces in a time of radical politics and authoritarian and technocratic military regimes, Cold War diplomacy, and the transnational flows of expertise and capital.

scholarly journals КАРАКАЛПАКСКИЙ ПОСТОЯЛЫЙ ДВОР ШАРБАҚ

2021 ◽  
pp. 287-293
Author(s):  
Г.А Акимниязова
Keyword(s):  
20Th Century ◽  
Social Life ◽  
Urban Infrastructure ◽  
Short Stay ◽  
The Social ◽  
Economic Ties ◽  
The City

Развитие торговли и экономических связей привело к необходимости строительства специальных заведений, предназначенных для торговцев, путников, с помещениями для вьючных животных. Это в свою очередь привело к появлению постоялых дворов. У каракалпаков постоялый двор назывался шарбақ. Он были двух видов: для кратковременного пребывания, расположенный в черте города недалеко от базара, и долговременного пребывания, устанавливавшийся при въезде в город. Второй из них предпочитали путешествующие издалека. Посетители же первых постоялых дворов останавливались в нем для разгрузки привезенного для продажи товара, реализовав который в течение дня, покидали заведение. Функции шарбақ заключались не только в предоставлении приюта, возможности отдыха, размещения товаров и животных, но и в общении, обмене новостями. В базарные дни сюда стекались жители со всей округи для того, чтобы узнать последние новости. Для старшего поколения шарбақ был, в первую очередь местом проведения досуга. Постоялый двор играл важную роль в жизни каракалпаков. Об этом свидетельствует их количество. К середине XX века постоялый двор начинает терять свою значимость в связи с развитием городской инфраструктуры и появлением гостиниц. The development of economic ties entailed arranging special establishments for traders and travelers, with premises for beasts of burden. This resulted in the construction of hostelries. The Karakalpaks called them sharbak. There were two types of sharbaks: located within the city near the bazaar, intended for a short stay, and installed at the entrance of the city for the long-term visitors. Travelers from far away preferred the second type. Guests of the first type of hostelries usually stayed there just to unload the goods and sell them at the bazaar during the day. The sharbaks not only provided shelter, recreation, and accommodation of goods and animals, but also served as a place for communication and news exchange. On market days, residents from all over the area flocked there to find out the latest news. For the older generation, sharbak was a place of leisure. The hostelry played an important role in the social life of the Karakalpaks, which is evidenced by their large number. By the middle of the 20th century, the sharbak began to lose its significance due to the development of urban infrastructure and modern hotels

scholarly journals UM ESTUDO DE CASO SOBRE A IMPLANTAÇÃO DE UM AMBIENTE DE SEGURANÇA DE REDES DE COMPUTADORES

2019 ◽  
Vol 9 (1) ◽  
pp. 119-139
Keyword(s):  
Network Management ◽  
Computer Network ◽  
City Hall ◽  
Demilitarized Zone ◽  
Local Areas ◽  
It Department ◽  
Secure Environment ◽  
Definition Of ◽  
The City

This paper presents a case study involving the deployment of a secure environment on the computer network at the City Hall in Palmeira das Missões - RS, throughout the definition of a physical and logical infrastructure, supported at concepts of management of computer networks and information security. Through the creation of Vlans (Virtual Local Areas Networks) and definition of DMZ (Demilitarized Zone) defined to achieve the level of security and network management required by the IT department, as well as provide greater reliability and integrity of information that travel on the network so that the users can perform their tasks more dynamically in a secure and agile environment. The main contribution of this case study was the implementation of a security and management in the computer network at the City Hasll in Palmeira das Missões – RS.

scholarly journals Solar Irradiance Reduction Using Optimized Green Infrastructure in Arid Hot Regions: A Case Study in El-Nozha District, Cairo, Egypt

2021 ◽  
Vol 13 (17) ◽  
pp. 9617 ◽  
Author(s):  
Wesam M. Elbardisy ◽  
Mohamed A. Salheen ◽  
Mohammed Fahmy
Keyword(s):  
Climate Change ◽  
Urban Heat Island ◽  
Green Infrastructure ◽  
Solar Irradiance ◽  
Urban Trees ◽  
Heat Island ◽  
Physiological Equivalent Temperature ◽  
Urban Climatology ◽  
Urban Heat ◽  
The City

In the Middle East and North Africa (MENA) region, studies focused on the relationship between urban planning practice and climatology are still lacking, despite the fact that the latter has nearly three decades of literature in the region and the former has much more. However, such an unfounded relationship that would consider urban sustainability measures is a serious challenge, especially considering the effects of climate change. The Greater Cairo Region (GCR) has recently witnessed numerous serious urban vehicular network re-development, leaving the city less green and in need of strategically re-thinking the plan regarding, and the role of, green infrastructure. Therefore, this study focuses on approaches to the optimization of the urban green infrastructure, in order to reduce solar irradiance in the city and, thus, its effects on the urban climatology. This is carried out by studying one of the East Cairo neighborhoods, named El-Nozha district, as a representative case of the most impacted neighborhoods. In an attempt to quantify these effects, using parametric simulation, the Air Temperature (Ta), Mean Radiant Temperature (Tmrt), Relative Humidity (RH), and Physiological Equivalent Temperature (PET) parameters were calculated before and after introducing urban trees, acting as green infrastructure types that mitigate climate change and the Urban Heat Island (UHI) effect. Our results indicate that an optimized percentage, spacing, location, and arrangement of urban tree canopies can reduce the irradiance flux at the ground surface, having positive implications in terms of mitigating the urban heat island effect.

scholarly journals Skateboarding as a tool for reading the city

2019 ◽  
Author(s):  
Polina Yu. Krutskikh
Keyword(s):  
Urban Youth ◽  
Analytical Approach ◽  
Youth Sports ◽  
Urban Infrastructure ◽  
Complex Nature ◽  
Academic Context ◽  
The Common ◽  
The City

Modern urban youth sports cultures are notable for their diverse and complex nature. The question arises as to what analytical approach should be used to study their multifaceted character. Using the St Petersburg skateboard scene as an example, the article shows the advantages in applying the concept of the post-sport cultures to understand how the common functions of urban infrastructure are redefined, what trends exist on the scene, how they shape the meanings attributed to them by the scene participants, and how those signs are read.  The study also employs the solidarity approach to describe the interactions between the scene participants through the ideas and ideological controversies shared by them. The focus of the paper is how to apply solidarity approach to study the nature of urban post-sport cultures based on St Petersburg skateboard scene case study. Given the lack of Russian publications on the topic, the study is also aimed at inscribing the Russian skateboarding experience into the Western academic context.

Urban afforestation and its ecosystem balance contribution: a bibliometric review

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Patrik Gustavo Wiesel ◽  
Elias Dresch ◽  
Eduardo Rodrigo Ramos de Santana ◽  
Eduardo Alcayaga Loboestan
Keyword(s):  
Bibliometric Analysis ◽  
Well Being ◽  
Urban Trees ◽  
Environmental Benefits ◽  
Urban Centers ◽  
Content Type ◽  
Heat Islands ◽  
Ecological Relationships ◽  
Bibliometric Review ◽  
The City

PurposeUrbanization is characterized mainly by changes in land use and conversion of natural areas into built environments, as well as by a series of impacts, such as loss of biodiversity, which interfere with the proper functioning of ecological networks.Design/methodology/approachThus, the authors apply a bibliometric analysis using the term “Urban Trees” in the “Web of Science” database, between 2009 and 2019, as a keyword to include all urban green structures and identify the main aspects of urban ecological relationships. They found 8,367 published articles.FindingsThis review identified the main countries and research institutions that operate in urban afforestation. In general, developing countries seek to understand the environmental benefits that urban afforestation can provide, demonstrating the importance of maintaining existing green areas in urban centers to promote the balance of the ecosystem. It depends directly on the flow of ecosystem services provided by green infrastructures in the city, contributing significantly to carbon sequestration, retention of particulate matter, mitigation of heat islands and reduction of surface runoff, directly favoring the health and well-being of the population. The authors conclude that the actions currently implemented in urban afforestation, especially to increase the richness and abundance of species, will be decisive for the future of urban centers and the construction of more sustainable and egalitarian cities.Originality/valueThis work sought to develop a bibliographic research based on information obtained by bibliometric analysis that has the ability to identify trends and volumes of scientific production in a given area of knowledge.

scholarly journals High-density QTL mapping of leaf-related traits and chlorophyll content in three soybean RIL populations

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Kaiye Yu ◽  
Jinshe Wang ◽  
Chongyuan Sun ◽  
Xiaoqian Liu ◽  
Huanqing Xu ◽  
...  
Keyword(s):  
Chlorophyll Content ◽  
Photosynthetic Efficiency ◽  
Plant Architecture ◽  
Seed Quality ◽  
Leaf Size ◽  
Yield Potential ◽  
Size And Shape ◽  
Genetic Components ◽  
Leaf Size And Shape ◽  
Mapping Populations

Abstract Background Leaf size and shape, which affect light capture, and chlorophyll content are important factors affecting photosynthetic efficiency. Genetic variation of these components significantly affects yield potential and seed quality. Identification of the genetic basis for these traits and the relationship between them is of great practical significance for achieving ideal plant architecture and high photosynthetic efficiency for improved yield. Results Here, we undertook a large-scale linkage mapping study using three mapping populations to determine the genetic interplay between soybean leaf-related traits and chlorophyll content across two environments. Correlation analysis revealed a significant negative correlation between leaf size and shape, while both traits were positively correlated with chlorophyll content. This phenotypic relationship was verified across the three mapping populations as determined by principal component analysis, suggesting that these traits are under the control of complex and interrelated genetic components. The QTLs for leaf-related traits and chlorophyll are partly shared, which further supports the close genetic relationship between the two traits. The largest-effect major loci, q20, was stably identified across all population and environments and harbored the narrow leaflet gene Gm-JAG1 (Ln/ln), which is a key regulator of leaflet shape in soybean. Conclusion Our results uncover several major QTLs (q4–1, q4–2, q11, q13, q18 and q20) and its candidate genes specific or common to leaf-related traits and chlorophyll, and also show a complex epistatic interaction between the two traits. The SNP markers closely linked to these valuable QTLs could be used for molecular design breeding with improved plant architecture, photosynthetic capacity and even yield.

scholarly journals Approach to Urban Environmental Justice Using Exploratory Spatial Data Analysis. The Case of Valencia’s Monumental Trees

2020 ◽  
Vol 12 (18) ◽  
pp. 7760
Author(s):  
Alfonso Gallego-Valadés ◽  
Francisco Ródenas-Rigla ◽  
Jorge Garcés-Ferrer
Keyword(s):  
Spatial Distribution ◽  
Data Analysis ◽  
Environmental Justice ◽  
Spatial Data ◽  
Urban Trees ◽  
Spatial Data Analysis ◽  
Exploratory Spatial Data Analysis ◽  
The Public ◽  
Object Of Study ◽  
The City

Environmental justice has been a relevant object of analysis in recent decades. The generation of patterns in the spatial distribution of urban trees has been a widely addressed issue in the literature. However, the spatial distribution of monumental trees still constitutes an unknown object of study. The aim of this paper was to analyse the spatial distribution of the monumental-tree heritage in the city of Valencia, using Exploratory Spatial Data Analysis (ESDA) methods, in relation to different population groups and to discuss some implications in terms of environmental justice, from the public-policy perspective. The results show that monumental trees are spatially concentrated in high-income neighbourhoods, and this fact represents an indicator of environmental inequality. This diagnosis can provide support for decision-making on this matter.

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