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Post‐glacial Permian coal‐bearing sedimentary successions are traditionally interpreted as fluvially deposited within the Gondwanaland continental set‐up throughout the globe. Recent attempts to reinterpret such successions in terms of marine flooding events, mainly based on sedimentological and ichnological attributes, raised doubt on the existing palaeogeographic model of the Late Palaeozoic Gondwanaland. Reassessing these sedimentary successions using other proxies, like petrographic and geochemical properties, may provide more reliable clues to improve the present understanding. In this paper, petrographic and geochemical analysis of sandstones, sandstone–mudstone heteroliths, and mudstones of the early Permian Barakar Formation of Lower Gondwana Supergroup, Raniganj coal Basin, India, is presented to understand the provenance, palaeoweathering pattern and palaeodepositional conditions. Petrographically, the sandstones are arkosic to sub‐arkosic in nature, with abundant unstable components and heavy minerals. Clay minerals in the matrix and the mudstones are dominated by kaolinite, illite‐smectite with authigenic glauconite, indicating a marine diagenetic realm. Mineralogical assemblage attests to sedimentation in craton interior passive margin conditions. Geochemically, the lithounits show large variations in major element and trace element (including rare earth element) concentrations. Chemical index of alteration and A–CN–K ternary plot indicate moderate to strong chemical weathering, leading to deposition of compositionally immature sediments close to their source without much recycling. Ratios of major elements (e.g., MgO, K2O, Fe2O3, Al2O3, and SiO2) signify a continental–marine transitional depositional environment developed in a stable passive margin setting under gradually warming up climatic conditions. Trace element ratios manifest an estuarine depositional setting during Barakar sedimentation, comparable with modern major river mouth estuaries. Thus, this paper provides unequivocal evidence of significant marine influence during sedimentation in the Lower Gondwana basins in India, particularly during the Permian time, and signifies the importance of re‐examining the so called “continental fluvial” coal‐bearing deposits as considerably marine‐influenced. The interpretations provide important clues in understanding and reconstructing the Permian Lower Gondwana palaeogeography in eastern peninsular India. [ABSTRACT FROM AUTHOR]

As a renewable energy, biofuel has greatly attracted worldwide attention due to the growing demands for cleaner sources of energy as an intervention to mitigate the serious environmental problems associated with fossil fuel consumption. As an important non‐food biodiesel plant, Pistacia chinensis has a promising prospect for bioenergy development. Based on the principles of multifactor integrated assessment, this paper provides an operational method for comprehensively evaluating the marginal land resources suitable for developing the plantation of Pistacia chinensis in Shaanxi province, China. The results show that the areas of marginal land resources suitable and fairly suitable for growing Pistacia chinensis in Shaanxi province are 1.21 million hectares and 4.45 million hectares, respectively. The suitable land resources are mainly located in Hanzhong (0.44 million hectares), Ankang (0.30 million hectares), and Shangluo (0.31 million hectares), most of which are moderate dense grassland (accounting for 50.65%), dense grassland (accounting for 21.83%), shrub land (accounting for 8.62%), and sparse forest land (accounting for 15.32%). The comparison between the results and field work data suggests that the pixel size of spatial data and soil organic matter content have important impacts on the final results. The outcome of this research can be used to implement specific policies for developing Pistacia chinensis in China and other countries especially the countries along the Silk Road. [ABSTRACT FROM AUTHOR]

In this paper, landscape ecological risk in Qinling Mountain was studied. Using the remote sensing images of Landsat TM and DEM data in 1984, 2000, 2005, and 2014, an ecological risk assessment model was constructed, and landscape ecological risk indexes were calculated for four time periods 1984, 2004, 2005 and 2014. The spatial distribution of ecological risk was obtained with ArcGIS and geostatistics, and changes in the landscape patterns and spatiotemporal characteristics of ecological risk were analysed. As shown in the results; (a) from 1984 to 2014, the landscape pattern index of Qinling forest area was relatively stable; fragmentation and segregation decreased, and dominance and area increased. The fragmentation and separation of cultivated land increased over time, and the geographical distribution of cultivated land diversified, while its dominance decreased. (b) The areas of extremely low and extremely high ecological risk level in the study area is gradually reduced. But the area of high ecological risk level increased obviously. The extremely high ecological risk area was mainly distributed in the middle and south‐eastern regions. The extremely low and low risk areas were mainly distributed in the low hilly areas of northern Qinling. [ABSTRACT FROM AUTHOR]

“The Belt and Road” refers to the Silk Road Economic Belt and the 21st‐Century Maritime Silk Road. In this paper, the Guanzhong–Tianshui region is selected as a case study, which is located at the starting point of the Silk Road Economic Belt. First, the spatial distribution maps of plant and soil types are obtained based on the TM remote sensing images and the soil texture data. The boundaries of the third‐level watershed are extracted based on the digital elevation model data. Then the corresponding mathematical models are used to evaluate the ecological water requirements of the plant–soil systems. Also, the spatial distribution characteristics are analysed at the landscape scale and the third‐level watershed scale. The results show that the spatial differences of ecological water requirement in the Guanzhong–Tianshui are obvious. At the plant–soil landscape scale, the ecological water requirement per unit area of the woodland‐clay loam is the highest, about 0.4777 m3/m2, while that of the grassland‐gravel loam is the lowest, about 0.2813 m3/m2. At the third‐level watershed scale, the ecological water requirement per unit area in the Weihe watershed (Jinghezhangjiashan above) is the highest, about 0.4123 m3/m2, while that in the Weihe watershed (Longmen to Sanmenxia) is the lowest, about 0.3002 m3/m2. The study offers scientific references for the regional ecological environment protection and ecosystem management. [ABSTRACT FROM AUTHOR]