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The excessive use of chemical fertilizers causes many problems for which solutions are being sought in a variety of agricultural production systems. From the perspective of paying attention to the health requirements of aquatic animals in terms of water quality, this study investigated the impact of chemical fertilizer application on water quality in a rice (Oryza sativa L.; Cultivar "Qingxiangruangeng," accession number: 2014004)–eel (Monopterus albus) coculture system in Shanghai, China. Chemical fertilizer was applied four times—as base fertilizer, rejuvenated fertilizer, tiller fertilizer, and ear granule fertilizer—during the production process of a rice–eel coculture system (June to October 2020). Changes in the water quality parameters of rice field's surface water and ring ditch water in the regular chemical fertilizer group (RF) and no chemical fertilizer group (NF, the control) were compared before and at 24 h, 48 h, and 72 h after the chemical fertilizer application. The results for the analyzed physical and chemical indexes of each water area before and after four fertilizations revealed several consistent trends. First, the pH, dissolved oxygen (DO), water temperature (T), and chemical oxygen demand (COD) of either water area were similar between the NF and RF groups, whereas their total nitrogen (TN), total ammonia nitrogen (TAN), and total phosphorus (TP) levels differed significantly. After adding the above fertilizer containing nitrogen and phosphorus, 24 h later, the TN, TAN, and TP content had already increased significantly in comparison with the control. The maximum average content of TAN and nitrite nitrogen (NO2−-N) in the ring ditch water reached 12.30 mg/L and 0.37 mg/L, respectively, at 24 h after the chemical fertilizer application. Nonlinear regression analysis results showed that there was a significant positive relationship TN (δTN) and TAN (δTAN) vis-à-vis the nitrogen content of the fertilizer. The results of this study provide a timely empirical reference and data support for improving fertilizer management in rice–eel coculture systems. [ABSTRACT FROM AUTHOR]

Understanding the characteristics of passenger vehicle use is the prerequisite for effective urban management. However, it has been challenging in the existing literature due to the lack of continuously observed data on passenger vehicle use. Thanks to the advances in data collection and processing techniques, multi-day vehicle trajectory data generated from volunteered passenger cars provide new opportunities for examining in depth how people travel in regular patterns. In this paper, based on a week's operation data of 6600 passenger cars in Shanghai, we develop a systematic approach for identifying trips and travel purposes, and classify vehicles into four categories using a Gaussian-Mixed-Model. A new method is proposed to identify vehicle travel regularities and we use the Z Test to explore differences in travel time and route choices between four types of vehicles. We find that commercially used vehicles present high travel intensity in temporal and spatial aspects and the use intensity in elevated roads is higher for household-used commuting vehicles than semi-commercially used vehicles. The methodologies and conclusions of this paper may provide not only theoretical support for future urban traffic prediction, but also guidance for employing customized active traffic demand management measures to alleviate traffic congestion. [ABSTRACT FROM AUTHOR]

The maturation of digital(ized) consumption, together with the amplification of cities' initiatives in response to local and global environmental challenges, has placed goods transport, an essential but impactful activity, at the forefront of urban stakeholders' scrutiny. High-performance and low-impact supply chains benefit from the presence of logistics facilities in proximity to goods' destinations. This development of logistics facilities in high-demand areas, which are essentially urban, dense and mixed-use, we term 'proximity logistics'. It is the focus of this article. Proximity logistics entails extending and refining networks of logistics facilities towards urban cores and allows them to counteract some of the undesirable effects that their historic tendency to outward migration (or logistics sprawl) potentially brings about. The phenomenon is established around the world, albeit to different extents. In this article, we discuss the trends supporting proximity logistics' development and present a typology of facilities it could entail, followed by case studies of five cities: New York (United States); Paris (France); Seoul (South Korea); Shanghai (China); and Tokyo (Japan). We characterize the state of practice of logistics facilities in each city's dense, mixed-use areas, compare the characteristics in light of their context and distill learnings in support of sustainable land use patterns. [ABSTRACT FROM AUTHOR]

The concept of "consumer city" has reshaped the growth and prosperity of major cities in the world. Although the literature has extensively documented the role of central cities in generating jobs, there has been limited empirical evidence on how those cities have developed into agglomerations of consumption opportunities by offering metropolitan residents high-quality consumer goods and services. We use large-scale cellular signaling data to distinguish commuting and consumption connections between the Shanghai City and a suburban town Huaqiao. Through the clustering algorithm, we categorize residents of Huaqiao into groups according to their frequency of visiting Shanghai and length of the visits. Results show that while travel time does not differ across the three groups of trips, non-commuters' consumption trips are more spatially expansive and intensive than the others. The average per capita visit frequencies also indicate the outstanding role of consumption-oriented travel. Spatial lag models suggest that although non-commuters are more sensitive to travel time than commuters, they are still willing to make long consumption trips to access the consumer goods and services the central city can provide. The findings would encourage city managers and planners to reconsider the roles of major cities, and redefine them as space that best match the changing demand of people. • Concept of "consumer city" is tested with cellular signaling data in Shanghai. • Commuting and consumption travel of residents in a suburban town are studied. • Core city accommodates demand for accessing various socioeconomic opportunities. • Non-commuters' consumption trips are more expansive and intensive than commuting trips. • Non-commuters are willing to make long consumption trips to the core city. [ABSTRACT FROM AUTHOR]

To combat urban challenges such as air pollution stemming from excessive vehicle use, policy makers have adopted various driving restriction policies (DRPs) worldwide. Although previous studies have extensively justified the effects of citywide DRPs on air quality, little attention has been paid to urban core-focused license-plate-based DRPs (UCLDRPs), which have gained increasing popularity among major cities. To bridge this gap, we carried out an empirical evaluation of the short-run effectiveness of Shanghai's UCLDRPs in improving air quality using difference-in-differences (DID) modeling approaches on high-frequency air quality data. The results show that UCLDRPs did not lead to any reduction of air pollutants including NO 2 , PM 2.5 , and PM 10 during peak hours (the restricted time window) in the inner ring area (the restricted area), while contributing to a 14% increase in the concentration of CO. Moreover, the air quality of surrounding zones (the 5 km buffer area) got worse as the concentration of CO and PM 10 raised by 16% and 8% respectively. Results also justified the temporal-spatial spillover effects in the dynamics: the concentrations of CO and PM 10 got increased by 10%-20% in the 5 km buffer area within time periods right before or after the restricted time windows. [ABSTRACT FROM AUTHOR]

In the era of economic globalization and the e-commerce boom, the demand for urban logistics has been rapidly growing in terms of both scale and intensity. The spatial clustering of logistics facilities and their associated environmental consequences has caused growing concern. This study analyzes the spatial evolution of logistics facilities and establishes a series of regression models to explore the driving factors of logistics facility location choice using a high-resolution grid-based data set. The results show that as the urban highway network gets improved, transportation costs are more balanced across space. Therefore, the distribution of logistics facilities is less regionally constrained and more widely located in space. The spatial evolution of logistics facilities was driven not only by demand of land uses and industries but also by transport supply and urban structure. Land use planning including the planning of industrial parks is among the important driving forces affecting the spatial location of logistics facilities, although the effects vary across types of logistics facilities. This study aims to provide a sustainable development-oriented policy path for regional development by proposing an analytical framework that reconsiders spatial location choice factors as a means of controlling logistics environmental negative externalities. [ABSTRACT FROM AUTHOR]