Changsha General Survey of Natural Resources Center
[Objective]Formation is the carrier of the geological environment. Studying the correlation between formation and ecological characteristics is helpful to correctly understand the causes of ecological problems and serve the precise restoration of the ecological environment. [Method] In this paper, Luoshan County, which has both low mountains, hills and plains, is selected as the research area. On the basis of combing the geological background and tectonic evolution characteristics of Luoshan County, 13 geological formation types are divided; Based on profile survey, data statistics, hydrological parameter test and other means, the geological characteristics of four typical geological formations were analyzed from the four aspects of rock, soil, hydrogeology and terrain slope, and the correlation between ecological characteristics and geological formations was discussed. Taking soil erosion as an example, the spatial distribution, cause analysis and restoration suggestions are carried out based on geological formation. [Results] The results show that, from the Cretaceous acid magmatic rock formation in the low mountain and hilly area to the Cretaceous continental pyroclastic rock-volcanic formation in the hilly area, the thickness of the parent material layer and soil layer has been increasing, and the content of gravel and sand has increased. Gradually less, the particle size of the soil becomes smaller, so the soil texture gradually changes from gravel soil (sandy loam), sandy loam, silty loam, and loam; the vegetation transitions from natural secondary forest to artificially planted economic forest, and the vegetation type changes from diversity It tends to be single, but the tree height and diameter at breast height are increasing; the correlation between geological formation and ecological characteristics is strong. The genetic analysis based on geological formations shows that soil erosion develops differently in different formations, among which the Cretaceous acidic magmatic rock formation is the most serious. The problem of soil erosion has a strong correlation with the terrain slope, mineral composition and grain size of rocks in different formations. [Conclusions] Using formation as a unit to analyze ecological characteristics has better pertinence and application prospects, and can more reflect the constraints of geology on ecology. The research results can provide a geological basis for accurate restoration of ecological protection and soil erosion in Luoshan County.