Caracterización ambiental como herramienta para la toma de decisión en la planificación urbanística del partido de Berazategui

The Municipality of Berazategui is located to the northeast of the province of Buenos Aires and composes the second ring of the Conurbano Bonaerense. The relief of the zone is conformed mainly by two environments, continental and littoral-estuárico. The party is crossed by four main streams and minor courses that are to a greater or lesser extent influenced by anthropic activity. In general, the area has a high landscape heterogeneity and environmental variability throughout its whole length. Water risk has been analyzed, distinguishing three classes. In an important proportion of the territory of Berazategui, especially in the littoral-estuarial zone, the phreatic level is shallow or directly outcrop, which constitutes zones of high risk. The great population growth that has occurred in recent years resulted in the growing occupation of areas that are unfit for urbanization. That is why, in face of possible problems, the main objective of this contribution is to conduct an environmental characterization in Berazategui and analyze the aptitude for urbanization in the different sectors of the area under consideration. Geomorphic units have been determined as environmentally homogeneous areas, which can be useful for future planning in the territory. For each of them the aptitude for urbanization has been determined. The Loessic Plain has the highest aptitude while the most compromised zones correspond to the estuarial littoral zone and the floodplains of the rivers.El partido de Berazategui se encuentra localizado al noreste de la provincia de Buenos Aires y compone el segundo cordón del Conurbano Bonaerense. El relieve de la zona está conformado principalmente por dos ambientes, continental y litoral-estuárico. El partido se encuentra atravesado por cuatro arroyos principales y cursos menores que están en mayor o menor medida influenciados por la actividad antrópica. En líneas generales, el área cuenta con una alta heterogeneidad de paisaje y variabilidad ambiental a lo largo de toda su extensión. Se ha analizado el riesgo hídrico diferenciándose tres clases. En una importante proporción del territorio del Partido, especialmente en la zona litoral-estuárica, el nivel freático se encuentra somero o directamente aflorante, lo que constituye zonas de peligrosidad alta. El gran crecimiento poblacional ocurrido en estos últimos años ha resultado en la ocupación creciente de zonas poco aptas para la urbanización. Es por ello que frente a las posibles problemáticas el objetivo principal de esta contribución es realizar una caracterización ambiental en el Partido de Berazategui y analizar la aptitud para la urbanización en los diferentes sectores del área considerada. Se han determinado como áreas ambientalmente homogéneas a las unidades geomorfológicas las que pueden ser útiles para una futura planificación en el territorio. Para cada una de ellas se ha determinado la aptitud para la urbanización. La Planicie loéssica presenta la mayor aptitud mientras que las zonas más comprometidas corresponden a la zona litoral estuárica y las planicies de inundación de los cursos

Risks of airborne pollution accidents in a major conurbation: Case study of Zhangjiakou, a host city for the 2022 Winter Olympics

The number of airborne pollution accidents is second only to that of water-borne pollution accidents, in recorded environmental disasters. Acute casualties and public health costs have prompted many airborne pollution risk analyses. To date, few assessment methods have been carried out at regional-scale to quantify acute airborne pollution risk. Herein, a Hybrid Simulation and Risk Analysis approach, involving a systematic combination of simulation, risk ranking, and standardized analysis, is proposed at regional scale. Gaussian and heavy-gas models are utilized in the simulation process, and acute exposure limits preferentially adopted in the risk analysis. The case study shows that 34 of 243 townships in Zhangjiakou City of north China, one of the twin cities selected to host the 2022 Winter Olympics, are threatened by airborne risk sources. It is found that the accidental air pollution risk is comparatively higher in the Xuanhua and Wanquan conurbations. High-risk chemical enterprises (312–432 risk scores) are mostly located near urban areas with high population density where many people are vulnerable receptors to potential air pollution accidents. The resulting risk map indicates that acute airborne pollution from Zhangjiakou would not be a threat either to the proposed Olympic site at Chongli or to downwind Beijing