Members’ Publication

As bike-share systems proliferate across the US, their potential as a way of expanding opportunities for those most underserved by the transportation system merits a deeper understanding of its current users. In this study, we examine the rate of bike-share adoption by individuals from different socio-demographic groups and living in different bicycling contexts. We explore how individuals incorporate bike-share service into their travel patterns for different travel purposes and change their use of other modes. Data are from a two-wave survey of bike-share users and a parallel household survey of residents in the Sacramento region. Our modeling results for bike-share adoption and use frequency show that low-income individuals are less likely to adopt bike-share but use the service more frequently than other income groups when they do adopt. Low-income users, people of color, and non-auto owners are more likely than other groups to use bike-share frequently for many trip purposes. Individuals living in areas with a stronger biking culture and surrounded by bike infrastructure are less likely to adopt the service and less likely to use it for purposes other than commuting. All users change their use of other modes when they incorporate bike-share into their travel patterns, but low-income individuals, people of color, and non-auto owners would be more severely impacted if the service were to stop. Our results add new insights into the use of bike-share, a service that can enhance social equity while also addressing sustainability.

The COVID-19 pandemic has had enormous effects on human life and the environment, particularly freshwater ecosystems, on a global scale. Despite its numerous effects, the pandemic has improved the quality of the environment, allowing devastated ecosystems to recover. During the COVID lockdown period, many researchers observed positive amendments in environmental quality in various parts of the world. Due to increased industrialization and urbanization over the past several decades, Dhaka's peripheral rivers have grown highly polluted. In this study, an attempt was made to illustrate the post-covid surface water quality scenario of Bangladesh's hihgly contaminated Turag River. Therefore, for the first time, a GIS-based spatial analysis of water quality index was used to endeavor to quantify 16 water quality parameters (pH, EC, temperature, turbidity, salinity, TDS, DO, Na+, K+ Ca2+, Mg2+ Cl-, Cu, Pb, Fe, and Cd) in the river Turag. Thus, it could serve as a reference work for future researches in Bangladesh. After calculating the WQI for the collected samples, it was determined that the water quality status at all sampling stations was extremely poor because each WQI was greater than 100. Using the Kriging method of interpolation, the encroaching WQS were predicted and visually represented using GIS maps. The findings of this study are particularly concerning, as all recorded WQS samples surpassed the standard limits. Based on these findings, we urged for the rapid deployment of proper water management practices and policies in order to safeguard and manage the water resources.

Global and urban-induced local warming lead to increasing heat risk in cities. The rapid increase in urban population, weak infrastructure, poverty, as well as an ageing population, make the risk more acute in developing cities. However, heat risk is not uniformly distributed and a detailed exploration of the link between urban characteristics and local variations in heat risk is needed to aid targeted mitigation. In this paper, we demonstrate a fine-grained heat risk map using existing data combined with expert opinion in a humid tropical city (Colombo, Sri Lanka) with the objective of highlighting the relative heat risk as a function of physical and socioeconomic conditions across the city. We then simulate the effects of shading and greening on the ‘high’ heat risk areas, and greening on the ‘low’ heat risk areas, to show that a combined approach will be needed to reduce risk at ‘high’ risk areas. In ‘low’ risk areas, maintaining the green cover is crucial to heat risk reduction. The paper, thus, establishes a protocol for detailed heat risk mapping with existing data and points to the differing importance of shading and greening in different parts of the city, thus, showing where, and to what extent, mitigation actions could be beneficial.

This book encourages children to create friendship with birds.