Research On Spatio-Temporal Data Model Of Land Reclamation In The Mining Area

Coal is the important energy source in China, occupies about 70% of the disposable energy production and expense, it plays the enormous role in promoting the national economy, while the negative effect to ecological environment in the mining area appears simultaneously, underground mining causes the ground subsidence, large amount of cultivated land is destroyed, soil erosion and land desertification are intensifying, the ecological environment is worsened, seriously affecting the regional sustainable development.The land resource information has the spatio-temporal dynamic characteristic affected by the underground exploitation in the mining area. It is of great significance to land resource management and the decision making of land reclamation planning to organize the temporal data of ground subsidence effectively, query historical data conveniently, and keep the real land information. Subsidence area and the damage degree are changing along with the constant underground exploitation, which is caused by the sequence events of underground working face exploitation. Based on the analysis of the current spatio-temporal data model, considered the land dynamic change characteristic and underground mining events, three kinds of spatio-temporal data model of organizing the land information in the mining area are proposed. The major contents of this dissertation are consists of five parts:(1) The current spatio-temporal data models are systematically summarized, the advantage and disadvantage of the exiting spatio-temporal data models and their applicable condition are analyzed. But any kind of data model among of the Mentioned in the dissertation cannot solve the mining area land reclamation spatio-temporal database construction well, so it needs to seek the appropriate spatio-temporal data model to express land dynamic change characteristic in the mining area.(2) The surveying methods of land information in the mining area are summarized firstly, based on the analysis of land destruction type and land quality’s evolution by the underground exploitation, the variation process of the mining surface characteristic and the spatio-temporal evolution of land reclamation, combining the present land investigation classification approach, in view of the land dynamic change, the subsidence land is classified. The content of this part is the foundation to further study the spatio-temporal data model of land dynamic change in the mining area.(3) Based on the analysis of the theory of characteristic-based modeling combined land dynamic change characteristic in the mining area, anylzing the theory of event-based modeling combined underground mining sequence events and ground destruction sequence events, the spatio-temporal data model based on characteristic and time-varying sequence of events is proposed in view of mining subsidence surveying datum. This model integrates ground events and underground events, it is helpful to study ground movement rule, the prediction parameters can be extracted easily, finally an example is applied to construct spatio-temporal database of the subsidence land.(4) Through the analysis of spatio-temporal reasoning theory and methods, combined with the existing mathematical prediction model of mining subsidence, the time "t" is introduced into the probability integral method. The size of the working face on the predicting moment can be obtained according to the mining schedule. The subsidence area and destroying degree of the future five years are predicted applying mining subsidence predicting software in Renlou mining area. Overlaying the movement and deformation contours with the road layer, the pipeline layer, the water layer, the cultivated land layer and the village house layerseparately, the statistics of the damage range and the damage degree are gained, these statistics datum can be used to plan the migration and land dynamic reclamation in the mining area.(5) Considering most mine area in the town or village, according to the objects of compensation for mining damage, The ground entities affected by underground exploitation can be classified point class, polyline class and polygon class in the light of the object-oriented approach. Point class includes wells, culverts and small bridges; polyline class includes roads, rivers, pipelines, polygon class includes village house, green land(including farmland, forests, orchards, vegetable land), ponds (lakes). Then the spatio-temporal data model based on events and objects is proposed, the spatio-temporal databases are constructed in accordance with displacement of these objects and their restoration record. This model can be used to build land reclamation spatio-temporal database, which can be applied to instruct ecological restoration reconstruction, especially land dynamic reclamation in the mining area.