Objective In order to research the evolution law of land subsidence and its subsidence potential,take the Wangsiying area in Beijing as an example,the characteristics of land subsidence in Wangsiying area "from point to surface" are analyzed and compared with multi−source fine monitoring data.

Methods The growth curve land subsidence model is introduced, and the land subsidence potential evaluation model based on multi−source data fusion is constructed by MATLAB.Based on Wangsiying ground land subsidence station, the mechanism analysis and prediction of layered land subsidence are carried out on "point"; Based on the regional leveling and dynamic monitoring data of regional groundwater level, the regional land subsidence evolution characteristics and land subsidence potential are evaluated.

Results (1) The land subsidence mainly occurs in the cohesive soil layer, and the development of land subsidence is directly proportional to the content of cohesive soil. The land subsidence amount and the land subsidence ratio of the shallow strata in Wangsiying area are getting smaller and smaller, while the land subsidence amount and the land subsidence ratio of the deep strata are getting larger and larger with time; The land subsidence rate slows down in the wet season and increases significantly in the dry season; After fitting the data of land subsidence and groundwater level, it is found that there is a certain correlation between them. The correlation increases with the increase of water level decline, and the correlation is positive; The development of land subsidence in Wangsiying area is relatively high,and the differential subsidence in the whole area is also very obvious. (2) The error values of the static leveling system of bedrock level and layered level and the manual leveling system for the data of the same monitoring point are very close to each other and conform to the normal distribution law. (3) It is predicted that the future land subsidence will be vertical. With the increase of time, the land subsidence of each layer will gradually decline, but the overall residual subsidence of the stratum still has a development space of about 100 mm. The middle and deep strata are the main "dominant strata" for the future land subsidence, and the land subsidence potential is large; Horizontally, the trend of land subsidence in the future is consistent with that in the current stage, but the overall rate is slowing down.

Conclusions The deep strata in Wangsiying area are the main subsidence "advantageous" layers, and the seasonal deformation characteristics of land subsidence are highly correlated with the dynamic changes in groundwater level. In the future, the land subsidence in this area will continue to slow down.