Analysis on the Interaction Between Vegetation and Soil Quality in Coal Mining Subsidence Area

Abstract

As a “bridge” connecting soil, atmosphere and water, the dynamic change of vegetation can reflect the change of ecological environment in coal mining subsidence area to a certain extent. However, relying on traditional methods to extract vegetation coverage information in a large range not only consumes huge human and material resources, but also has low accuracy. Therefore, this study uses satellite remote sensing technology to extract vegetation coverage in coal mining subsidence areas. Based on the spatial variation laws of soil water content, pH, alkali-hydrolyzed nitrogen, available phosphorus, available potassium and organic matter content in coal mining subsidence areas, considering the impact of different types of surface vegetation (grassland, shrubs and trees), this study analyzes the interaction and distribution of each factor under coal mining disturbances, and puts forward reasonable maintenance suggestions to reduce the impact of coal mining disturbances on ecology. The results showed that: (1) Soil water content was negatively correlated with soil pH, and the correlation between the two was the best in the one-year subsidence area (SA), among which the shrub land had the highest correlation, followed by grassland and arbor land. The influence between soil water content and soil pH is timely affected by coal mining subsidence, grassland and shrub land are more sensitive, and arbor land is more stable. Soil water content was positively correlated with soil fertility, and the correlation was the best in one-year SA, among which shrub land had the highest correlation, followed by arbor land and grassland. Soil pH was negatively correlated with soil fertility. The shrub land in the unmined area, the 1-year SA, and the 2-year SA had a high correlation with the arbor land, among which the shrub land in the 1-year SA had the highest correlation. (2) The correlation between vegetation coverage and soil physical and chemical properties (PCP) is the best between shrub forest land in 1-year SA and arbor forest land in 2-year SA, which is medium. At the initial stage of subsidence, the vegetation coverage and soil PCP of shrub forest land respond in time. After increasing the subsidence years, the vegetation coverage and soil PCP of arbor forest land respond significantly. (3) Increasing the coverage of surface vegetation can effectively improve or alleviate the damage caused by coal mining to the PCP of soil. Planting arbor and shrub forests in the mining area can better protect the soil and reduce the loss of water and fertility.