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The Three Gorges Reservoir Area (TGRA) is an important ecological barrier in the Yangtze River Basin, China. Therefore, it is of great importance to understand the spatio-temporal variation and the driving factors of production-living-ecological spaces for sustainable and high-quality development in the TGRA. This study investigated the dynamic variation of production-living-ecological spaces in the TGRA by employing land use data in 2000, 2005, 2010, 2015, and 2018, and detected the influencing factors by using the Geographic detector (GeoDetector). Results implied that the structure and dynamic trajectories of production-living-ecological spaces in the TGRA varied in both horizontal and vertical directions, and the study area was dominated by ecological space. A spatial orientation towards the northeast was detected in the evolution of production-living-ecological spaces during 2000–2018. In terms of quantity, the transition from ecological space (grassland and woodland) to agriculture land accounted for the largest proportion from 2000 to 2018. However, the reverse transition from agriculture land to ecological space has increased since 2000 with the efforts of “Grain for Green”. In terms of temporal scale, there was a fluctuating trend in production space with the continuous expansion of living space, while ecological space showed an inverted U-shaped trend during 2000–2018. The dynamic pattern of production-living-ecological spaces in the TGRA was influenced by both physical and socio-economic variables as basic determinants and dominant driving factors, respectively. Finally, the harmonization and protection of production-living-ecological spaces still require policy-makers’ efforts. This work may have potential in advancing our understanding about land use conflicts, and provide a reference for rational layout of spatial functions and the realization of sustainable development in the TGRA. [ABSTRACT FROM AUTHOR]

The Three Gorges of Yangtze River, southwest China, abundant in human and faunal fossils, and lithic artifacts, represents an important site complex for understanding hominin dispersion and adaptations during the Pleistocene. The Yumidong Cave is a newly-discovered Paleolithic site in this region which yielded a large number of animal fossils and lithic artifacts. U–Th dating in conjunction with biostratigraphic analysis indicated that the archaeological remains were deposited during a long sequence from ca. 400 to 8 ka (Middle Pleistocene to Holocene). Lithic technological analysis indicated an original material shaped on massive limestone blocks with chaîne opératoire consisted of selection, shaping and retouching. The volumetric structures of selected blanks are regrouped into three categories: structures with bevel(s), trihedral structure and convergent ones. The outline of cutting-edge is predonimated by denticulate ones, followed by saw-like ones, rostrum, convergent with a denticulate edge and beaked ones. Despite showing nothing in common with Europe, Africa, the Near East and even the Indian Subcontinent and northern China, the lithic assemblage of the Yumidong Cave exhibits a strong coherence and presents more similarity to mainland Southeast Asia with heavy, angular and massive stone tools made on pebble, cobble and without the Levallois, Discoid, and blade/bladelet phenomenon. The lithic assemblage of Yumidong Cave may represent material clues of a potential local technological center of origin in unique technical world of Central-South China and its uniqueness would be understandable as the result of a successful adaptation of hominids to a specific environment. Yumidong lithic material deconstructs the existing paradigm for a long period of time and presents new ideas and new facts for the technic evolution in South China. [ABSTRACT FROM AUTHOR]

This paper presents the results of an investigation of the Gongjiafang landslide with the volume of about 500,000 m 3 in the Three Gorges Reservoir region (TGR), occurred on 23 November, 2008. In this study, detailed geological and geomorphological surveys, in-situ and laboratory tests, and numerical simulation are carried out to reveal the failure mechanism of this landslide. The anaclinal rock slope is characterized mainly by a set of outward dipping and non-persistent joints, a hard stratum (limestone) in the middle portion and an underlying soft base (argillaceous limestone interbedded with shale). Because of the long-term intensive river erosion caused by periodic fluctuation of the reservoir water level, the soft rock masses at the toe of the slope were softened, or even washed away, inducing the first sliding-toppling failure at the toe. The collapse at the toe leaves the hard strata in the middle unsupported, like a “beam”. Thus, a conceptual “cantilever beam” model is proposed to explain the failure mechanism of the landslide. The DEM simulation further highlights the failure process with a complex rock topple-rock slide failure mode, i.e., first composite sliding and toppling occurred at the toe, a composite shear and flexure failure of the middle “cantilever beam” and a simultaneous overall sliding failure of the rock masses in the upper part of the slope. The results imply that preventing water erosion at the toe could be an effective way in landslide prevention and treatment in the study area. [ABSTRACT FROM AUTHOR]

Abstract: Chinese sturgeon (Acipenser sinensis Gray) is a kind of key protected fish in ChangJiang river. Recently the Three Gorges dam has run, the peak regulation process between the two dams has serious effect on the formed spawning sites. Based on the previous research results of suitable flow conditions about the spawning sites, this article builds a 2-D shallow water numerical model, calculates the flow conditions of the spawning sites in the process of peak regulation. The results show that the water depth and velocity are various and affect the spawning sites in one 24-hours process of peak regulation, as a whole, when the discharge is below 9000 m3/s and 7500 m3/s respectively, the two spawning sites will be affected seriously. [Copyright &y& Elsevier]

The paper reports the ground conditions in the Sanmashan area where people were relocated as a consequence of the impoundment of the Three Gorges Reservoir. Examination of the geology indicates the strong calcareous rocks were not only highly fractured to considerable depths but were also decalcified in the near surface layers. A combination of the highly fractured state and decalcified nature of the material resulted in significant changes in the bedrock parameters between the northern and southern parts of the study area; the southern area having been affected by the deep down-cutting of the Yangtze River, release of stress and the development of three large landslides. [ABSTRACT FROM AUTHOR]

Numerous landslides have occurred during the construction of the Three Gorges Reservoir of the Yangtze River. Although the underlying causal factor of these landslides was heavy rainfall, the construction process was the trigger of some of them. We report here a systematic study aimed at reconstructing the geological history of an ancient landslide and, based on our results, an evaluation of the role of the history on current landslide stability. Data from detailed field surveys and the studies on geological dating revealed that the Baiyian landslide was composed of five structural parts of different geological ages, such as a sliding belt, disturbed rocks, ancient colluvium, alluvium of the Yangtze River and slope wash. The succession of ancient climates, terraces and tectonic processes in the study area were examined from 300 ka ago. The evolutionary history of the Baiyian ancient landslide can be divided into five distinct stages: development, occurrence, deposition, collapse and disintegration. Some parts of the ancient landslide are currently prone to instability due to the combination effects of heavy rainfall and construction of the reservoir. [ABSTRACT FROM AUTHOR]