Study On The Relationship Between Landscape Pattern Dynamics And Surface Energy Changes In Mining Areas Drivenby Coal Mining

Pingshuo mining area,as an important coal-producing area in north Shanxi Province,has three open-pit mining areas with its unique coal resource conditions.It is of great significance for the ecological restoration and resource management of open-pit mining area to reveal the landscape pattern dynamics and surface energy changes and the relationship between them under the driving of coal mining.In this paper,Landsat remote sensing data were used to classify the six phases of land use data of mining area in 1990,2000,2010,2015,2017 and 2019 by means of supervision and classification method based on investigation and sampling,and the landscape level index and patch level index were combined to reflect the dynamic changes of landscape pattern.Based on SEBAL(Surface Energy Balance Algorithm for Land)model to the new flat Surface Energy parameters are calculated,and through the meteorological data and the measured data and model simulation data to validate the inversion results,based on the analysis of the different landscape features under the net radiation(Rn),upward shortwave radiation write(Rs?),emergent long wave radiation(RL?),the Surface temperature(Ts),normalized difference vegetation index(NDVI),Albedo change and the distribution of space and time,the following conclusions:(1)according to the classification of land use types in pingshuo mining area,the classification data were verified,and the data verification results of each year reached more than 80%.Each area found mine and stripping zone area from the overall trend for the growth state,both with a total area of 13.01 km2,20.65 km2,18.05 km2,19.79 km2,18.89 km2,21.31 km2,Ann too fort open-pit mine abandoned mines,stripping zone land into grassland/shrub land,grassland/arable land accounted for 55.72%,65.81%,50.14%,55.93%,49.13%,49.26%.Analysis of landscape LPI,AI,SHDI and other indexes showed that the overall trend was that the areas such as grassland,shrub and cultivated land generally showed a downward trend,with irregular shape and increasing degree of fragmentation.Mine pits,stripping areas,low crushing degree,regular shape,in a stable state for a long time.(2)the SEBAL model was used to invert surface energy-related parameters,and Rn and Ts were verified by the Chinese daily radiation data set and the Chinese daily surface climatic data set,respectively.The results show that RMSE of Rn is 19.38-21.67 w/m2,and R2 is 0.70-0.81.The Ts value RMSE was 1.86-2.78?,and R2 was 0.68-0.85 ?.The mean values of Rn in each year are in the range of 630-690 w/m2,Ts in the range of 27-31 ?,Albedo in the range of 0.124-0.148,and NDVI in the range of 0.217-0.375.The highest NDVI value is in the restoration area of the mining area,indicating that the restoration project carried out in the mining area has a better degree of restoration of the original pits and is higher than the vegetation coverage outside the region.The surface mergey of mining area is stable and the energy level is the highest.Most of the surrounding areas are restoration areas with a good degree of restoration,higher vegetation coverage and lower energy level than those outside.(3)local object types:the Rn values were distributed as>cultivated land>grassland/shrub>stripped area>bare land,and Ts values were distributed as>grassland/shrub>cultivated land>bare land>stripped area.The surface energy absorbed by bare land is affected by the spatial connectivity and patch area.The surface energy received by grassland/shrub and cultivated land is affected by the spatial connectivity,spatial fragmentation and surface coverage.