Protection and restoration of natural heritages in post-earthquake reconstruction: a case of Dujiangyan City The short-term effect of field camping on soil CO2 efflux in urban grassland Investigation and analysis of collapses and landslides on the Loess Plateau of East Gansu Province after the 5.12 Wenchuan Earthquake A review of the impacts of earthquake on mountain ecosystems: taking 5.12 Wenchuan Earthquake as an example