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The objective of this paper is to develop and demonstrate a fuel-based approach for emissions factor estimation for highway paving construction equipment in China for better accuracy. A highway construction site in Chengdu was selected for this study with NO emissions being characterized and demonstrated. Four commonly used paving equipment, i.e., three rollers and one paver were selected in this study. A portable emission measurement system (PEMS) was developed and used for emission measurements of selected equipment during real–world highway construction duties. Three duty modes were defined to characterize the NO emissions, i.e., idling, moving, and working. In order to develop a representative emission factor for these highway construction equipment, composite emission factors were estimated using modal emission rates and the corresponding modal durations in the process of typical construction duties. Depending on duty mode and equipment type, NO emission rate ranged from 2.6–63.7mg/s and 6.0–55.6g/kg–fuel with the fuel consumption ranging from 0.31–4.52 g/s correspondingly. The NO composite emission factor was estimated to be 9–41mg/s with the single-drum roller being the highest and double-drum roller being the lowest and 6–30g/kg-fuel with the pneumatic tire roller being the highest while the double-drum roller being the lowest. For the paver, both time-based and fuel consumption-based NO composite emission rates are higher than all of the rollers with 56mg/s and 30g/kg-fuel, respectively. In terms of time–based quantity, the working mode contributes more than the other modes with idling being the least for both emissions and fuel consumption. In contrast, the fuel-based emission rate appears to have less variability in emissions. Thus, in order to estimate emission factors for emission inventory development, the fuel-based emission factor may be selected for better accuracy. Implications: The fuel-based composite emissions factors will be less variable and more accurate than time-based emission factors. As a consequence, emissions inventory developed using this approach will be more accurate and practical. [ABSTRACT FROM AUTHOR]

While the Bolivian ‘post’ consultation about the contested construction of a highway through the TIPNIS has received a lot of attention, very little is known about the 27 prior consultations that have been concluded between June 2007 and February 2012 in its hydrocarbon sector. This article focuses on these procedures and presents three emblematic cases in more detail. It identifies frequent shortcomings of consultation practices like the ‘information hurdle’, irregularities, the limited decision-making power of affected local populations and the lack of transparency regarding the compensation payments. The article argues that consultations could be improved by complementing international human rights instruments on indigenous rights with insights from deliberative theories. It concludes that as long as local ideas of self-determined development remain subordinated to prioritized extractive industries, the right to free, prior and informed consent (FPIC) will remain distant, even in a plurinational state like Bolivia. [ABSTRACT FROM PUBLISHER]

Roads fragment habitat and pose a variety of threats to wildlife by restricting their physical movements or causing direct mortality. Wildlife crossing structures can mitigate some of these effects by simultaneously connecting fragmented habitat and reducing collisions between animals and traffic. This research develops two classes of spatial models for optimally locating crossing structures in situations where the goal is to connect discrete habitat patches that are fragmented by roads. The first group of models uses variations of minimum spanning forest (MSF) problems to select crossing structure locations in scenarios where the goal is to connect all habitat patches in the landscape. This article explores three variations: distance-based, intersection-weighted, and component-based MSFs. The second set of models includes newly developed integer programs with objectives that maximize interpatch connectivity given a fixed number of crossing structures. One of these integer programs maximizes overall connectivity in a landscape, and the other maximizes the connectivity of patches to a core reserve. We illustrated the models using hypothetical landscapes and applied them to a case study where the goal is to connect vernal pool habitat for amphibians. Results of the applications guide a discussion of the relative merits of each approach for meeting various conservation goals related to improving habitat connectivity in fragmented landscapes. More broadly, this article develops an analytical framework for dealing with habitat connectivity issues due to road network fragmentation as well as a new neighborhood graph and several spatial models. [ABSTRACT FROM AUTHOR]

The Northeast, strategically important yet economically underdeveloped, has been witnessing spurts of road building activities since independence. The need to establish connection with the rest of India following partition, the Chinese aggression, economic development, and trans-border connectivity are some of the main drivers which have been impelling the central government to construct roads in the region since independence. However, impediments such as terrain and climatic conditions, insurgency, and mismanagement of resources have also put brakes on the development of the road network in the region. The paper identifies the drivers and brakes, which have fashioned the evolution of the road network in the region and suggests some measures to overcome the hurdles. [ABSTRACT FROM AUTHOR]

Explores the changes in approaches to road building which have occurred in the past on South American tropics. How conservationists can remain effective in an era of increasingly decentralized planning and financing of infrastructure projects; Bolivia's Upper Madidi River basin; Brazil's atlantic forest.

This research sheds light on the concept of eco-friendly road construction which comprises eco-design, eco-extraction, eco-manufacturing, eco-construction, eco-rehabilitation, eco-maintenance, eco-demolition, and socioeconomic empowerment. It also revealed the challenges being faced in its adoption and the benefits derivable from its application. Furthermore, the effects of recycling PET plastic bottle wastes produced in North Central Nigeria in bituminous asphaltic concrete (BAC) used in flexible pavement construction were also evaluated. The mix design consists of 60/70 penetration-grade asphaltic concrete (5%), 68% coarse aggregate, 6% fine aggregate, and 21% filler using the dry process at 170°C. The optimum bitumen content (OBC) for conventional BAC was obtained as 4% by weight of total aggregates and filler. Polymer-coated aggregate (PCA)-modified BAC seems preferable because it has the potential to utilize more plastic wastes with a higher optimum plastic content (OPC) of 16.7% by weight of total aggregates and filler compared to that of 9% by weight of OBC achieved by PMB-BAC. For both PMB- and PCA-modified BAC, an increase in air void, void in mineral aggregate, and Marshall stability were observed. Eco-friendly road construction which recycles PET wastes should be encouraged by government considering its potential environmental and economic benefits. [ABSTRACT FROM PUBLISHER]