The Role of Road Infrastructure and Air Pollution in the Recent Suburbanization of India’s Cities

2017 ◽  
Vol 8 (2) ◽  
pp. 151-169 ◽  
Author(s):  
Matthew J. Holian ◽  
Kala Seetharam Sridhar

This article re-examines the suburbanization of Indian cities by calculating population density gradients, for a large number of urban agglomerations, using recent data and Mills’ two-point method. In the next step, we estimate multiple regression models to explore the determinants of suburbanization. This study presents several methodological advances over previous research, by incorporating new measures of transport infrastructure, air pollution and city–suburb income ratios as determinants of suburbanization of Indian cities. Our results clearly show that suburbanization is higher in urban areas with higher population and lower central city–suburban literacy ratios. We find some evidence that suburbanization is higher in urban areas with more road transport infrastructure, consistent with our expectations, though results concerning air pollution run counter to expectations. However, these could relate to caveats regarding the data and methods.

SLEEP ◽  
2022 ◽  
Author(s):  
Noor Adra ◽  
Haoqi Sun ◽  
Wolfgang Ganglberger ◽  
Elissa M Ye ◽  
Lisa W Dümmer ◽  
...  

Abstract Study Objectives Alterations in sleep spindles have been linked to cognitive impairment. This finding has contributed to a growing interest in identifying sleep-based biomarkers of cognition and neurodegeneration, including sleep spindles. However, flexibility surrounding spindle definitions and algorithm parameter settings present a methodological challenge. The aim of this study was to characterize how spindle detection parameter settings influence the association between spindle features and cognition and to identify parameters with the strongest association with cognition. Methods Adult patients (n=167, 49 ± 18 years) completed the NIH Toolbox Cognition Battery after undergoing overnight diagnostic polysomnography recordings for suspected sleep disorders. We explored 1000 combinations across seven parameters in Luna, an open-source spindle detector, and used four features of detected spindles (amplitude, density, duration, and peak frequency) to fit linear multiple regression models to predict cognitive scores. Results Spindle features (amplitude, density, duration, and mean frequency) were associated with the ability to predict raw fluid cognition scores (r=0.503) and age-adjusted fluid cognition scores (r=0.315) with the best spindle parameters. Fast spindle features generally showed better performance relative to slow spindle features. Spindle features weakly predicted total cognition and poorly predicted crystallized cognition regardless of parameter settings. Conclusion Our exploration of spindle detection parameters identified optimal parameters for studies of fluid cognition and revealed the role of parameter interactions for both slow and fast spindles. Our findings support sleep spindles as a sleep-based biomarker of fluid cognition.


2017 ◽  
Vol 17 (6) ◽  
pp. 4131-4145 ◽  
Author(s):  
Guannan Geng ◽  
Qiang Zhang ◽  
Randall V. Martin ◽  
Jintai Lin ◽  
Hong Huo ◽  
...  

Abstract. Spatial proxies used in bottom-up emission inventories to derive the spatial distributions of emissions are usually empirical and involve additional levels of uncertainty. Although uncertainties in current emission inventories have been discussed extensively, uncertainties resulting from improper spatial proxies have rarely been evaluated. In this work, we investigate the impact of spatial proxies on the representation of gridded emissions by comparing six gridded NOx emission datasets over China developed from the same magnitude of emissions and different spatial proxies. GEOS-Chem-modeled tropospheric NO2 vertical columns simulated from different gridded emission inventories are compared with satellite-based columns. The results show that differences between modeled and satellite-based NO2 vertical columns are sensitive to the spatial proxies used in the gridded emission inventories. The total population density is less suitable for allocating NOx emissions than nighttime light data because population density tends to allocate more emissions to rural areas. Determining the exact locations of large emission sources could significantly strengthen the correlation between modeled and observed NO2 vertical columns. Using vehicle population and an updated road network for the on-road transport sector could substantially enhance urban emissions and improve the model performance. When further applying industrial gross domestic product (IGDP) values for the industrial sector, modeled NO2 vertical columns could better capture pollution hotspots in urban areas and exhibit the best performance of the six cases compared to satellite-based NO2 vertical columns (slope  =  1.01 and R2 = 0. 85). This analysis provides a framework for information from satellite observations to inform bottom-up inventory development. In the future, more effort should be devoted to the representation of spatial proxies to improve spatial patterns in bottom-up emission inventories.


2021 ◽  
Vol 3 ◽  
Author(s):  
Jyothi S. Menon ◽  
Richa Sharma

The urban population is subjected to multiple exposures of air pollution and heat stress and bear severe impacts on their health and well-being in terms of premature deaths and morbidity. India tops the list of countries with the highest air pollution exposure and hosts some of the most polluted cities in the world. Similarly, Indian cities are highly vulnerable to extreme heat with the frequency of heatwaves expected to increase several-fold in urban areas in India. It is reported that mitigating air pollution could reduce the rural-urban difference of the incoming radiation thus resulting in mitigation of the urban heat island effect. Since the interaction between urban heat and air pollution is dynamic and complex, both these factors should be considered by the urban authorities in designing mitigation strategies. Given the multi-functional nature and cost-effectiveness of Nature-Based Solutions (NbS), they appear to be the most appropriate remedy for environmental issues of urban areas, particularly in developing countries. In addition to improving public health (through the reduction in air pollution and urban heat), NbS also provides a wide range of co-benefits such as reducing energy cost and health costs as well as conservation of biodiversity. This review is an attempt to understand the potentials of NbS in co-mitigating air pollution and urban heat in Indian cities. A framework for the planning and design of NbS in Indian cities is also proposed based on the review that could help city planners and decision-makers in addressing these two issues in an integrated manner.


2016 ◽  
Vol 164 (1) ◽  
pp. 32-36
Author(s):  
Piotr JAWORSKI ◽  
Sebastian JAROSIŃSKI ◽  
Azael CORTES CAPETILLO ◽  
Łukasz KAPUSTA ◽  
Adam ZIÓŁKOWSKI ◽  
...  

Air pollution has become an important worldwide problem. The European Commission credits road and water transport as the major source of NOx pollution, and of being responsible for around 50% of the total air pollution in urban areas. During the last decade, the use of SCR technologies have gained popularity as a method for NOx reduction, the technology is widely considered as one of the solutions for road transport emissions. This paper presents a review of the different SCR system designs derived from the various factors and regulations in the automotive industry which have influenced the technology, along with a parametric study of a proprietary SCR system for heavy duty application.


2020 ◽  
Vol 37 (6) ◽  
pp. 1873-1891
Author(s):  
Maryam Tajmirriyahi ◽  
William Ickes

Several studies have examined the role of self-esteem in self-disclosure while overlooking a potentially important confounding variable: self-concept clarity. Across three studies, we found an association between self-concept clarity and self-disclosure to one’s romantic partner. This incremental effect held even when the variance attributable to self-esteem was statistically controlled in a multiple regression analysis. Moreover, in two of the three studies, self-esteem was no longer a significant predictor of self-disclosure after controlling for the variance in self-concept clarity. These data suggest that self-concept clarity is an important predictor of self-disclosure—one that is conceptually and empirically distinct from self-esteem. That self-concept clarity tended to supplant self-esteem in the multiple regression models suggests that disclosing the specific aspects of the self that one clearly perceives (one’s attributes, goals, motives, values, etc.) might be more essential to everyday self-disclosure than disclosing only whether one has a globally positive or negative self-view. Future research should explore the causal relationships involved with the aid of experimental studies.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Tanushri Kamble ◽  
Sarika Pankaj Bahadure

PurposeThe urban population in Indian cities is increasing at an alarming speed. Accommodating such a huge population while sustaining the environment is a challenge in urban areas. Compact urban forms with high-density planning is claimed to be a sustainable solution in such situations. Thus, this approach needs to be tested for Indian urban areas.Design/methodology/approachThis paper formulates a neighbourhood sustainability assessment (NSA) framework for monitoring, assessing and managing the population density of urban neighbourhoods. The paper identifies context-specific built density indicators at the neighbourhood scale. It assesses the indicators in neighbourhoods with varying population density by physical and perceived measures. This helps in verifying the feasibility of density by physical density assessment and verifies the acceptability of density by perceived density assessment.FindingsWhen tested in the Indian context, the framework shows that although high-density neighbourhoods are sustainable, certain indicators may endorse differing densities. The result displays that high-density planning is sustainable compared to low- and medium-density neighbourhoods in the selected cities.Practical implicationsThe study demonstrates the application of formulated assessment system in three central Indian cities with useful results. Similar studies can be conducted to identify the gaps for improving sustainability and achieve a livable density pattern.Originality/valueAlthough sustainable development goals are part of new planning policies, there exist very few assessment systems to determine the sustainability of neighbourhoods, especially for density. The methodology will assist in developing sustainability assessment frameworks and encourage the practice of sustainability assessment in developing countries like India.


Author(s):  
Mehrdad Rafiepourgatabi ◽  
Alistair Woodward ◽  
Jennifer A. Salmond ◽  
Kim N. Dirks

Pedestrian exposure to traffic-related air pollution depends on many factors; including the nature of the traffic on nearby roads and the route characteristics. In this study, we investigated the effects of differences in vehicle fleet and transport infrastructure on children’s exposure to traffic-related air pollution during their morning walk to school in Auckland, New Zealand. Five pairs of routes to schools—each including a low and a high socioeconomic status (SES) school—were selected and traversed over 7–8 days for each pair while measuring particle number concentration (PNC) and GPS coordinates. At the same time, a sample of 200 license plates of cars from each school’s neighborhood was captured using videos, and the age of each car was extracted using an online database. Both the mean age of the cars and the percentage of old cars (>14 years) were found to be higher in the low SES areas. However, neither measure of vehicle age was associated with a significant difference in exposure to PNC for pedestrians. Route features including narrow footpaths and a higher density of traffic lights may be associated with higher levels of PNC exposure. These findings provide insight into the role of urban design in promoting healthy commutes to school.


2021 ◽  
Vol 11 (21) ◽  
pp. 10044
Author(s):  
Mohammad Reza Ramezani ◽  
Bofu Yu ◽  
Yahui Che

Total imperviousness (residential and non-residential) increases with population growth in many regions around the world. Population density has been used to predict the total imperviousness in large areas, although population size was only closely related to residential imperviousness. In this study, population density together with land use data for 154 suburbs in Southeast Queensland (SEQ) of Australia were used to develop a new model for total imperviousness estimation. Total imperviousness was extracted through linear spectral mixing analysis (LSMA) using Landsat 8 OLI/TIRS, and then separated into residential and non-residential areas based on land use data for each suburb. Regression models were developed between population density and total imperviousness, and population density and residential imperviousness. Results show that (1) LSMA approach could retrieve imperviousness accurately (RMSE < 10%), (2) linear regression models could be used to estimate both total imperviousness and residential imperviousness better than nonlinear regression models, and (3) correlation between population density and residential imperviousness was higher (R2 = 0.77) than that between population density and total imperviousness (R2 = 0.52); (4) the new model was used to predict the total imperiousness based on population density projections to 2057 for three potential urban development areas in SEQ. This research allows accurate prediction of the total impervious area from population density and service area per capital for other regions in the world.


Author(s):  
В.Б. Заалишвили ◽  
А.С. Кануков ◽  
К.В. Корбесова

Экономическое развитие всех регионов основано на доступе людей к товарам и услугам, которые обеспечиваются современной транспортной инфраструктурой. Автомобильный транспорт является основным способом транспортировки грузов и населения. В то же время положительные аспекты использования транспорта тесно связаны с такими негативными аспектами, как загрязнение окружающей среды и отрицательным влиянием на здоровье человека. На территории Республики Северная Осетия - Алания наибольший вклад в загрязнение окружающей среды вносит деятельность предприятий цветной металлургии и автотранспорта. Более 30 предприятий находится в промышленном узле г. Владикавказа, и их деятельность в той или иной мере связана с загрязнением атмосферного воздуха. Значительный вклад в загрязнение воздуха вносит автотранспорт, количество которого в г. Владикавказе, по данным Федеральной службы государственной статистики, за последние 20 лет увеличилось более чем в 2 раза. Цель исследования. Изучение основных источников загрязнения окружающей среды автомобильным транспортом, исследование взаимосвязей между уровнем загрязнения среды, интенсивностью движения и экологическим классом автомобильного транспорта. Установление показателя загрязнения окружающей среды автомобильным транспортом, характеризующего степень воздействия на окружающую среду и здоровье населения. Методы исследования. В ходе настоящей работы были собраны и проанализированы все имеющиеся данные по динамике объемов выбросов от стационарных источников и автотранспорта на территории РСО-А за 1997–2015 гг. Указанные данные обрабатывались с помощью корреляционного и регрессионного анализов. Результаты работы. Результаты исследований позволили установить, что прослеживается прямая зависимость или тренд между плотностью потока машин и загрязнением воздушной среды. Установлено, что выбросы от автомобильного транспорта на порядок превосходят стационарные источники. Предложен суммарный показатель Zатм загрязнения атмосферного воздуха, рассчитываемый как сумма отношений концентрации отдельных загрязнителей к соответствующим значениям ПДК за вычетом количества используемых показателей. The economic development of any country is based on the access of population to goods and services that are provided by modern transport infrastructure. Currently, road transport is the most common way of transporting goods and people. At the same time, the positive aspects of using transport are closely related to such negative aspects as environmental pollution and negative impact on public health. On the territory of the Republic of North Ossetia-Alania, the largest contribution to environmental pollution is made by the activities of non-ferrous metallurgy enterprises and vehicles. More than 30 enterprises are located in the industrial hub of the city of Vladikavkaz, and their activities to one degree or another are associated with atmospheric air pollution. A significant contribution to air pollution is made by motor vehicles.Their number in Vladikavkaz has more than doubled over the past 20 years, according to the Federal State Statistics Service. Aim. Study of the main sources of pollution of an urbanized area by road transport. The research and identification of the relationship between the level of environmental pollution, traffic intensity and the ecological class of road transport and the establishment of an indicator of environmental pollution by road transport, characterizing the degree of impact on the environment and safety of the population. Methods. In the course of this study, all the available data on the dynamics of emissions from stationary sources and vehicles on the territory of North Ossetia-A for 1997–2015 were collected and analyzed. These data were processed using correlation and regression analyzes. Results.The research results made it possible to establish that there is a direct relationship or trend between the flow density of cars and air pollution. It was found that emissions from road transport exceed stationary sources by an order of magnitude. A total indicator Zatm of atmospheric air pollution is proposed, calculated as the sum of the ratios of the concentration of individual pollutants to the corresponding MPC values minus the number of indicators used.


2021 ◽  
Vol 67 (2) ◽  
pp. 29-39
Author(s):  
Marek Minárik

Abstract This paper analyzes the importance of bimodal solutions in the rail-road transport of goods with an emphasis on the aspect of ecology within the geographical region of EU-28. Using the panel regression analysis in the period from 2010 to 2019, we are trying to confirm the dependence between the road and rail transport of goods by applying several freight units’ measures: the freight transport performance in tonne-kilometres, the freight transport performance in tonne-kilometres per thousand of USD, and the amount of goods transported in thousands of tonnes. The application of data to all selected freight units’ measures in the regression models confirms a relationship between road and rail transport. A direct relationship between these two modes of transport confirms the complementarity effect, which means that, in most cases, the goods transport solutions require the combination of road and rail mode, where the railway should be considered as the main transport/carrier, the road transport, however, should have the role of short pre-transport or post-transport. The ecological aspect of such bimodal solutions can also be emphasized since the railway transport is considered as an ecological mode.


Sign in / Sign up

Export Citation Format

Share Document