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Una evaluación a escala nacional del hundimiento de tierras en las principales ciudades de China
Zurui Ao1, Xiaomei Hu2,3, Shengli Tao2,3
1Beidou Research Institute, Faculty of Engineering, South China Normal University, Foshan 528000, China.
Resumen
China también.
Área de la Ciencia:
- Ciencias de la Tierra
- Ciencias del medio ambiente
- Planificación urbana
Sus antecedentes:
- La rápida urbanización de China presenta desafíos significativos.
- El hundimiento de la tierra representa una amenaza para la infraestructura urbana y las poblaciones.
Objetivo del estudio:
- Evaluar sistemáticamente el hundimiento de tierras en las principales ciudades chinas de 2015 a 2022.
- Proyectar la elevación futura de las tierras costeras con respecto al nivel del mar para el año 2120.
Principales métodos:
- Utilizó interferometría de radar de apertura sintética en el espacio (InSAR).
- Análisis de las tasas de hundimiento en las principales zonas urbanas y regiones costeras.
Principales resultados:
- El 45% de las tierras urbanas se hunden más de 3 mm/año; el 16% se hunden más de 10 mm/año.
- La subsidencia afecta al 29% y al 7% de las poblaciones urbanas, respectivamente.
- Para 2120, el 22-26% de las tierras costeras podrían estar por debajo del nivel del mar debido al hundimiento y al aumento del nivel del mar.
Conclusiones:
- El hundimiento de tierras es un problema generalizado en las ciudades chinas, impulsado por factores como la retirada de agua subterránea y la construcción.
- Necesidad urgente de medidas de protección reforzadas para mitigar los impactos de los hundimientos y los riesgos de inundación costera.
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