Geochemistry Process from Weathering Rocks to Soils: Perspective of an Ecological Geology Survey in China

Abstract

Ecological characteristics are very important for the Earth’s environment and human lives. Recently, more attention has been paid to the ecological problems in the world. The soil and its parent materials/rocks serve as the supporting materials for the ecological system on the Earth’s surface. The ecological characteristics in one region are associated with or even dependent on the soil-forming process. Thus, the study of the weathering process of parent materials/rocks is important for our understanding of the geological genesis of ecological problems. In this study, three typical ecological problems in China are introduced: land salinization in the north, the desertification of land in the northwest, and Karst rocky desertification in the south. We chose 23 typical profiles for observation and sampling. The soil-forming processes in these areas were investigated by geochemical research, and eco-geology models were subsequently established to explain the profound relationship between vegetation cover and the soil-forming process. Our work first focuses on the geochemical methods used to explore these ecological issues, emphasizing the contribution of the geological genesis to the ecological characteristics. Using geochemical methods, such as the chemical index of alteration (CIA), major element and trace element distribution characteristics, the formation processes, and characteristics of bedrock-weathering soils under diverse epigenetic geological settings were determined. Eco-geology models were then developed by evaluating the vertical structure and material composition of soil, the characteristics of elemental migration during soil formation, and the enrichment and loss of elements in the supporting layers and their repercussions.

Spatiotemporal Variation Characteristics and Driving Force Analysis of Precipitation Use Efficiency at the North Foot of Yinshan Mountain

“…The northern foot of the Yinshan Mountain agricultural and pastoral ecotone is located in the middle of Inner Mongolia, bordering the Yinshan Mountain Range to the south and the Mongolian Plateau pastoral area to the north. It spans east longitude 107 [17]. The geomorphic features are mainly high plains, low hills, and basins, showing the structure of high in the south and low in the north.…”

Practical Exploration of Eco-Geological Survey Mapping in Qinghai–Tibet Plateau: Framework, Standard and Preliminary Cost Estimation

“…The regional eco-geological mapping work in China started relatively late. Since the deployment and implementation of the "1:250,000 Tieling City Sheet Eco-Geological Survey" project in 2003, the technical and methodological system of eco-geological survey has been initially established through continuous exploration and practice and is currently being promoted and practiced throughout the country [13][14][15][16].…”

“…By investigating the ecological pattern in the source region of the Yellow River within 13.2 of ten thousand kilometers, the spatial characteristics and distribution laws of water resources and vegetation resources in the region were explored, and the types, degrees and evolutions of ecological problems such as grassland desertification, wetland shrinkage and ecological service function degradation were investigated; moreover, the controlling and influencing factors were analyzed and the formation mechanism was studied. The mode and measures of ecological protection and restoration were put forward [14].…”