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Objective Soil contamination by heavy metals is a pervasive issue, and this paper investigates the spatial distribution of Pb, As, and Cd in the groundwater-soil-rice system in the Changshou district of Chongqing. We also assess their exposure risk and predict their potential changes in the future. Method Geostatistical techniques, ArcGIS, and the target hazard quotients (THQ) methods were used to assess the risk of the three metals entering food chain. Based on these results, we predicted their potential changes and distribution up to 2036. Result Pb, As, and Cd in groundwater, soil and rice co-existed spatially, with their concentrations higher in the southwest than in the northeast. The THQ model did not showed risk of rice consumption for adults (THQ (As, Pb, and Cd) <1), but showed that there was slight risk of Cd (THQCd=1.12) and Pb (THQPb=1.05) for children. The model predicted substantial differences in the content of Pb, As, and Cd between different three management scenarios: ideal, no human intervention, and severe pollution until 2036. While the contents of the heavy metals were predicted to decrease by 4% to 8% under the ideal scenario in 2036 compared to the current level in 2021, allowing severe pollution to continuously happen is expected to increase heavy metal content by 1.51 to 1.72 times the current level.Conclusion Industries are the primary source of heavy metal pollution in Changshou district. Regarding the exposure risk to children and vulnerable people, and current pollution level, strict measures, including controlling discharge of industrial waste into soils and remediating contaminated soils are essential to reducing heavy metal contents in soil and alleviating them entering food chain. [ABSTRACT FROM AUTHOR]

Extreme rainfall events have become an increasing component of the annual precipitation in China, which caused amounts of geological disasters, especially in Southwest China. At approximately 7 a.m. (Beijing time) on July 13, 2020, a catastrophic soil and rock landslide occurred in Baima Town, Wulong District, Chongqing, China. With a length of 750 m and a width of 125 m to 260 m, the landslide carried approximately 1.4 × 106 m3 of rock and soil debris and destroyed eight houses, two main roads, a shale gas pipeline, and a large amount of farmland. After the landslide failure, the accumulation zone still deformed responding to continuous rainfall. The failure mechanism of the landslide was analyzed based on the geological conditions, deformation process, and triggering factors. The research shows that the Niuerwan landslide had a complex deformation process. According to the deformation characteristics, the landslide is divided into five parts: the source area, the compression area, the rapid-sliding area, the landslide-affected zone, and the accumulation area. The source area was triggered by continuous torrential rainfall and controlled by mudstone and bedding plane. The variation of the microrelief in the study area has a significant effect on the failure model of the landslide. Precipitation triggered the failure of the steep source area which impacted the middle part. Eventually, a continuous sliding surface developed along with the weak layer, giving rise to catastrophic failure. Moreover, the accumulation area at the steep slope toe rapidly moved downward to form a debris flow under the combined action of the geological conditions and rainfall. The Niuerwan landslide is a complex rainfall-induced landslide with a unique evolution process, which can provide some useful information for the early warning and deformation mechanism of landslides in similar geological settings. [ABSTRACT FROM AUTHOR]