scholarly journals Seed Quality of Larix sibirica Ledeb. Depending on the Distance between Forest Areas and Pollution Sources around Ulaanbaatar City of Mongolia

2021 ◽  
pp. 23-35
Author(s):  
Bayarsaikahan Udval ◽  
◽  
Sukhbaatar Gerelbaatar ◽  
Tserenbaljir Dashzeveg ◽  
Anatoly Lobanov ◽  
...  
Keyword(s):  
Seed Germination ◽  
Forest Ecosystems ◽  
Seed Quality ◽  
Site Index ◽  
Reproductive Organs ◽  
Larix Sibirica ◽  
Pollution Sources ◽  
City Center ◽  
Randomized Sampling ◽  
The City

Seed quality and seed germination are the major indicators determining the success of regeneration and structure in natural forest ecosystems. This study focuses on problems associated with seed quality and seed germination under air pollution impacts in the surrounding forest ecosystems of Ulaanbaatar city of Mongolia. The objectives were to test whether there was any negative effect of air pollutants on the site index, and to analyze the relationship between seed quality and distance from the city center (maximum pollution). The study was carried out in natural larch forests (Larix sibirica Ledeb.) growing in the vicinity of the capital of Mongolia. A total of eight 100×100 m (1 ha) sample plots were laid out using completely randomized sampling design along the main wind direction. Remoteness from the city center was 10, 15, 20 and 30 km both to the north and to the south. Results showed a high variation in stand mean height (p > 0.001) and diameter (p > 0.001) among selected forest areas. In general, all sampled forests belonged to bonitet / quality classes III, IV and V, which are considered as relatively poor growing conditions in terms of site index. Therefore, greater site index and seed quality were observed in the most distant locations from the city center, and contrary, the poorest seed quality was detected in locations close to the city center. This emphasizes that forests growing close to pollution sources exist with a potential risk of degradation, and their reproductive organs are more sensitive to the effects of pollutants.

Accuracy of On-site Consistent Origin-Destination Estimation Method for Measuring the Actual Numbers of Consumer Shop-around Movements within the City Center of Hanoi, Vietnam

2012 ◽  
Vol 42 (2) ◽  
pp. 439-455 ◽  
Author(s):  
Saburo SAITO ◽  
Tran Ngoc HUY ◽  
Masakuni IWAMI ◽  
Takahiro SATO ◽  
Kosuke YAMASHIRO ◽  
...  
Keyword(s):  
Estimation Method ◽  
City Center ◽  
The City

Urban Development Strategies of City Centers: The Case of Rafah City, Palestinian Territories

2014 ◽  
Vol 8 (3) ◽  
pp. 195
Author(s):  
Omar S. Asfour ◽  
Samar Abu Ghali
Keyword(s):  
Urban Development ◽  
Gaza Strip ◽  
Geographic Location ◽  
Development Strategies ◽  
Functional Requirements ◽  
City Center ◽  
Palestinian Territories ◽  
The Gaza Strip ◽  
The City ◽  
Commercial Center

City centers worldwide are perceived as essential parts of the city, where city memories are preserved and its identity is expressed. They are planned to satisfy the functional requirements and pleasurable qualities of the city. Under the accelerating urbanization of the modern city, several challenges face these centers including demographic, economic, and environmental challenges. This requires a continuous and incremental urban development process based on clear strategy and action plans. Thus, this study focuses on urban development strategies of city centers, with a focus on Rafah city located in the Gaza Strip, Palestinian Territories. The geographic location of this city near the Palestinian-Egyptian borders makes it a promising commercial city at local and regional levels. Thus, the current situation of Rafah city center has been analyzed, and several development strategies have been proposed. This has been done through a field survey based on observation and a questionnaire directed to city center users. It has been found that there is a great potential of Rafah city center to be developed as a commercial center. In this regard, several strategies and required actions have been proposed in the fields of transportation, environmental quality, shopping activities, investment opportunities, and visual perception.

Spatial and Temporal Differences in Weekday Travel Durations Between Private-for-Hire Transportation Services and Transit in the City Center

2021 ◽  
pp. 036119812110197
Author(s):  
Baxter Shandobil ◽  
Ty Lazarchik ◽  
Kelly Clifton
Keyword(s):  
Transportation Network ◽  
Central City ◽  
Temporal Analysis ◽  
Time Of Day ◽  
City Center ◽  
Transportation Services ◽  
Regulatory Frameworks ◽  
Transit Services ◽  
Level Information ◽  
The City

There is increasing evidence that ridehailing and other private-for-hire (PfH) services such as taxis and limousines are diverting trips from transit services. One question that arises is where and when PfH services are filling gaps in transit services and where they are competing with transit services that are publicly subsidized. Using weekday trip-level information for trips originating in or destined for the city center of Portland, OR from PfH transportation services (taxis, transportation network companies, limousines) and transit trip data collected from OpenTripPlanner, this study investigated the temporal and spatial differences in travel durations between actual PfH trips and comparable transit trips (the same origin–destination and time of day). This paper contributes to this question and to a growing body of research about the use of ridehailing and other on-demand services. Specifically, it provides a spatial and temporal analysis of the demand for PfH transportation using an actual census of trips for a given 2 week period. The comparison of trip durations of actual PfH trips to hypothetical transit trips for the same origin–destination pairs into or out of the central city gives insights for policy making around pricing and other regulatory frameworks that could be implemented in time and space.

scholarly journals Simulating the effects of redesigned street-scale built environments on access/egress pedestrian flows to metro stations

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Yanan Liu ◽  
Dujuan Yang ◽  
Harry J. P. Timmermans ◽  
Bauke de Vries
Keyword(s):  
Built Environment ◽  
Route Choice ◽  
Local Area ◽  
Destination Choice ◽  
Built Environments ◽  
Renewal Processes ◽  
City Center ◽  
Metro Station ◽  
Route Choice Behavior ◽  
The City

AbstractIn urban renewal processes, metro line systems are widely used to accommodate the massive traffic needs and stimulate the redevelopment of the local area. The route choice of pedestrians, emanating from or going to the metro stations, is influenced by the street-scale built environment. Many renewal processes involve the improvement of the street-level built environment and thus influence pedestrian flows. To assess the effects of urban design on pedestrian flows, this article presents the results of a simulation model of pedestrian route choice behavior around Yingkoudao metro station in the city center of Tianjin, China. Simulated pedestrian flows based on 4 scenarios of changes in street-scale built environment characteristics are compared. Results indicate that the main streets are disproportionally more affected than smaller streets. The promotion of an intensified land use mix does not lead to a high increase in the number of pedestrians who choose the involved route when traveling from/to the metro station, assuming fixed destination choice.

scholarly journals Selecting Freight Transportation Modes in Last-Mile Urban Distribution in Pamplona (Spain): An Option for Drone Delivery in Smart Cities

Energies ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4748
Author(s):  
Adrian Serrano-Hernandez ◽  
Aitor Ballano ◽  
Javier Faulin
Keyword(s):  
Public Transportation ◽  
Smart Cities ◽  
Freight Transportation ◽  
City Center ◽  
Analytic Hierarchy ◽  
Freight Logistics ◽  
Transportation Modes ◽  
Last Mile ◽  
Urban Distribution ◽  
The City

Urban distribution in medium-sized cities faces a major challenge, mainly when deliveries are difficult in the city center due to: an increase of e-commerce, weak public transportation system, and the promotion of urban sustainability plans. As a result, private cars, public transportation, and freight transportation compete for the same space. This paper analyses the current state for freight logistics in the city center of Pamplona (Spain) and proposes alternative transportation routes and transportation modes in the last-mile city center distribution according to different criteria evaluated by residents. An analytic hierarchy process (AHP) was developed. A number of alternatives have been assessed considering routes and transportation modes: the shortest route criterion and avoiding some city center area policies are combined with traditional van-based, bike, and aerial (drone) distribution protocols for delivering parcels and bar/restaurant supplies. These alternatives have been evaluated within a multicriteria framework in which economic, environmental, and social objectives are considered at the same time. The point in this multicriteria framework is that the criteria/alternative AHP weights and priorities have been set according to a survey deployed in the city of Pamplona (Navarre, Spain). The survey and AHP results show the preference for the use of drone or bike distribution in city center in order to reduce social and environmental issues.

scholarly journals The Use of Electrostatic Field to Improve Soybean Seed Germination in Organic Production

Agronomy ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1473
Author(s):  
Zlatica Mamlic ◽  
Ivana Maksimovic ◽  
Petar Canak ◽  
Goran Mamlic ◽  
Vojin Djukic ◽  
...  
Keyword(s):  
Seed Germination ◽  
Electrostatic Field ◽  
Seed Quality ◽  
18Th Century ◽  
Soybean Seed ◽  
Organic Production ◽  
Initial Growth ◽  
Physical Treatment ◽  
Soybean Seedlings ◽  
Dark Green

Soybean production in the system of organic agriculture is not very demanding, and this has been well documented both through experimental results and commercial production. However, one of the biggest problems in organic production is the lack of adequate pre-sowing treatments. Therefore, the aim of this study was to examine the effect of the electrostatic field. This is a physical treatment that was first used for seed treatment in the 18th century but has mostly been neglected since then. Seeds of five soybean genotypes with differently colored seed coats (yellow, green, dark green, brown, and black) were included in this study. The seeds were exposed to different values of direct current (DC) with the following voltages: 0 V (control), 3 V, 6 V, and 9 V, to which the seeds were exposed for 0 min (control), 1 min, and 3 min. After exposing the seeds to the electric field, the physiological properties of seeds and seedlings at the first stage of growth were evaluated. The results show that the effect of the electrostatic field on seed quality depends on the genotype, voltage, and exposure time. The application of DC can be a suitable method for improving seed germination and the initial growth of soybean seedlings. In addition, the results indicate that it is necessary to adjust the DC treatment (voltage and duration of exposure of seeds) to particular genotypes since inadequate treatments may reduce the quality of seeds.

scholarly journals Estimating Demand for a New Travel Mode in Boise, Idaho

2021 ◽  
Vol 13 (3) ◽  
pp. 1209
Author(s):  
Mandar Khanal
Keyword(s):  
Road Network ◽  
Travel Demand ◽  
Stated Preference ◽  
State University ◽  
University Campus ◽  
City Center ◽  
Road Congestion ◽  
The Us ◽  
Potential Mode ◽  
The City

The 20,000-student Boise State University campus is located about 3 km from the center of the city of Boise. There is a significant amount of travel between the campus and the city center as students and staff travel to the city to visit restaurants, shops, and entertainment centers. Currently, people make this trip by car, shuttle bus, bike, or walking modes. Cars and shuttle buses, which share the same road network, constitute about 76% of the total trips. As road congestion is expected to grow in the future, it is prudent to look for other modes that can fulfill the travel demand. One potential mode is an aerial tramway. However, an aerial tramway is not a common mode of urban travel in the US. This research describes how the stated preference method was used to estimate demand for a mode that does not currently exist. An online stated preference survey was sent out to 8681 students, faculty, and staff and 1821 valid responses were received. Only about 35% of the respondents expressed their willingness to choose an aerial tramway for various combinations of cost and convenience of the new mode. Respondents were also found to favor convenience over cost for the new mode.

scholarly journals Impact of COVID-19 Pandemic on Retail Structure in Barcelona: From Tourism-Phobia to the Desertification of City Center

2021 ◽  
Vol 13 (15) ◽  
pp. 8215
Author(s):  
Lluís Frago Clols
Keyword(s):  
Multiple Scales ◽  
Real Estate Market ◽  
Structured Interviews ◽  
City Center ◽  
Urban Theory ◽  
The Real Estate ◽  
Tourist Flows ◽  
Before And After ◽  
The Impact ◽  
The City

COVID-19 has meant major transformations for commercial fabric. These transformations have been motivated by the collapse of consumer mobility at multiple scales. We analyzed the impact of the collapse of global tourist flows on the commercial fabric of Barcelona city center, a city that has been a global reference in over-tourism and tourism-phobia. Fieldwork in the main commercial areas before and after the pandemic and complementary semi-structured interviews with the main agents involved highlight the relationship between global tourist flows and commercial fabric. The paper shows how the end of global tourism has meant an important commercial desertification. The end of the integration of the city center into global consumer flows has implications for urban theory. It means a downscaling of the city center and the questioning of traditional center-periphery dynamics. It has been shown that the tourist specialization of commerce has important effects on the real estate market and makes it particularly vulnerable. However, the touristic specialization of commercial activities as a strategy of resilience has also been presented. This adaptation faces the generalized commercial desertification that drives the growing concentration of consumption around the online channel.

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