What is the impact of subsidence?

The subsidence of the stratum has a considerable impact on the natural ecological environment and the quality of human life. The disasters caused by it are as follows:
(1) The declined storage capacity of the groundwater resource causes the consolidation in the stratum. The thickness and porosity of the stratum were both declined and therefore the amount of the storage of groundwater was on decrease, which causes the groundwater resources in the subsidence area to be easily drained. 
(2) The low-lying terrain is prone to flooding. The subsidence area of flooding and flooding strata is low-lying due to the accumulation of historical subsidence, which changes the original drainage slope and make it difficult to drain. In the coastal areas, the ground is lower than the sea level because of the low-lying terrain. Due to the declination of the elevation of the top of the dike, the seawall lost its’ protection and therefore the seawater overflow would happen occasionally.
(3) Damage to buildings, engineering structures and maintenance systems and facilities. The drop of the groundwater level leads to the increase of the effective stress of the stratum and the compaction. The ground structures or bridge piers and abutments, etc., are damaged due to the increase in the subsidence rate. The running water, gas pipelines and other dimensions The raw pipeline and sewer leaked due to bending damage.
(4) The transformation of the environment and ecology is affected by the low-lying terrain in the subsidence area. Some of the land transforms into the wetland gradually, which is result from the stagnant water for a long term.