Holocene resistant substrate and their roles in ecological safety of the Mu Us sandy land, Northern China

Resistant substrata are the sediments that are abundant in organic matter and outcropped as near-vertical cliff faces due to erosion. Palaeoenvironment research on resistant substrata (including lacustrine and peat sediments and palaeosols) is an important aspect of Quaternary science. Previous studies in the Mu Us sandy land in Northern China have focused on paleoclimatic evolution and aeolian activity, but the relationships between resistant substrata and modem human activity, and their role as animal habitats, are poorly understood. In this study, we used remote-sensing images and field investigations to produce a synthesis of the distribution of resistant substrata, and subsequently analyzed their roles in ecological safety. The results showed that they are closely related to the presence and economic activity of the local people who use them as sources of stable litter for animals, or for human dwelling places, and for agriculture. Our findings indicate that because of the value of eutrophic peat as a natural fertilizer and its function as a water-retaining layer, the location of modern agricultural zones is closely related to the distribution of ancient peatland. We also formulate a preliminary plan for the use of peatland for the development and extension of modern agriculture. in addition, we also consider its role as a protective layer preventing the reworking of the underlying sands and the potential risks if it is overexploited. Our research is part of an attempt to focus attention on the relationships and potential applications of Quaternary research to environmental management and economic development of the region, emphasizing its utility for policy-makers and main stakeholders. Specifically, we anticipate that our study will provide a reference for subsequent efforts to balance economic development and resource conservation in this region.