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Bianfudong (pinyin for Bat Cave) is a paleolithic site that was recently discovered in Heqing, Yunnan in southwestern China. Several hominin fossils, stone artifacts and more than 69,000 mammal fossils were unearthed in 2019. The hominin fossils and stone artifacts were excavated from the upper part (layers 1–12) of the section with an age range of 180–70 ka BP. Some large mammal fossils and micromammalian remains were collected from the lower part of the section (layers 22–30), which has an age >180 ka BP. This paper describes the micromammalian fossils collected from layers 25–30 and analyzes the fauna composition and paleohabitats. A total of 638 micromammal specimens represent 12 species, including 11 extant species i.e. Euroscaptor longirostris , Blarinella wardi , Anourosorex squamipes , Crocidura vorax , Eothenomys (Anteliomys) chinensis , E. (A.) proditor , Apodemus chevrieri , Ap. draco , Ap. latronum , Micromys minutus , and Niviventer confucianus , and one extinct species Anourosorex qianensis. The two arvicolid Eothenomys species dominate, both in the number of identified specimens and the minimum number of individuals. The composition of the Bianfudong micromammalian fauna can be compared with the faunas of Sanjiacun in Chenggong of Yunnan Province, Mawokoudong in Bijie and Xinglongdong in Fengjie, Guizhou Province. Using the random forest model with modern meteorological data, we calculated the mean annual precipitation (MAP) and the mean annual temperature (MAT) for all 11 living species in the Bianfudong. The MAP was inferred as 1008.04 mm, close to modern data in the Heqing area, while the MAT was slightly lower at 12.84 °C. The dominance of Eothenomys also supports a slightly cooler climate during the late Middle Pleistocene in the Heqing area. [ABSTRACT FROM AUTHOR]

The Shuiyindong gold mine in Guizhou is used as a case study in this paper to study patterns of dust pollution occurring with traditional electric-rake operation. In particular, the study uses the northern quarry of the twenty-third line in the first middle section of the second mining area and establishes a three-dimensional simulation model of equal size. It uses Computational Fluid Dynamics (CFD) to simulate and analyse the airflow traces and distribution of dust concentration in the relevant roadway during each stage of the electric-rake operation. The simulation results show that the airflow in the working roadway has a spiral movement and produces reverse dirty-wind circulation towards the end. Dust flows out of the working roadway from the 8th second of operation, and dust concentration reaches a peak in the working roadway at the 12th second of operation at an average dust concentration of 37.5 mg/m³. The dust concentration drops rapidly from the 120th second and reaches the maximum dust concentration permitted for operation at the 180th second of operation. The validity of the simulation is tested by comparing the actual measured data at the site with the simulation results. Finally, the simulation results are analysed using violent Python, and the solution is used to divide the roadway into areas according to the human breathing range. The paper analyses the distribution of dust concentration at an average human breathing height, providing an established theoretical basis for dust-control work in mines. [Display omitted] [ABSTRACT FROM AUTHOR]

"Carbon Peaking" and "Carbon Neutralization" is the strategic direction and key period in the current stage of ecologic civilization construction. Green finance refers to making the financial industry a guide and supervisor of other industries. Green finance will help other industries save energy and reduce emissions to achieve "Carbon Peaking" and "Carbon Neutralization" at an early date. This paper takes Zhejiang, Jiangxi, Guangdong, Guizhou and Xinjiang provinces, which were approved as green finance reform pilot zones in 2017, as examples, and uses synthetic control method to study the constraint effect of the local carbon emissions in pilot zones. The results show that Guizhou has the best emission constraint effect. Jiangxi Province has a certain degree of emission constraint effect. Zhejiang, Guangdong and Xinjiang have no emission constraint effect. The following placebo test results show that the experiment is stable and robust. By combining the actual pilot zones policy schemes and experimental results of the five provinces, this paper concludes that the main reason for the differences in emission constraint effects of the five pilot zones are the differences in the policy selection and the different characteristics of the provinces. Based on this result, relevant policy suggestions are put forward. [ABSTRACT FROM AUTHOR]

Previous provenance studies on bronze drums mainly focused on ore sources, yet ignored the significance of big bronze drum casting, which represents the highest level of bronze manufacturing techniques, as an important part of the bronze industry of a frontier region under the specific historical background. This paper, for the first time, not only presented the analytical results of the composition and the microstructure of 50 new samples from big bronze drums, but also compared their lead isotope to the published data of 196 samples from 7 types of bronze drum, as well as 112 ore samples from Guangxi, Yunnan, Guizhou Province and Vietnam. In addition, this paper introduced the casting tradition of bronze drums through both of composition analysis and metallographic examination. The comparison of lead isotope between the above 7 types and 4 regions indicated that there existed a very close relation among the bronze drums, and the local metal ore sources were generally employed to cast drums according to the convenient principles as well as the sphere of tribal influence. Nonetheless, both exchange and communication existed. [ABSTRACT FROM AUTHOR]

• Different dimensions of wellbeing present heterogeneous trends, encouraging to resort to a multidimensional index for an inclusive overview on Chinese development based on household microdata. • Between 2011 and 2015 the average level of multidimensional wellbeing stagnated. Although a slight decrease in well-being is nominally recorded, the overall trend is stable when controlling for other phenomenon (such as the ageing of the sample). • Individual characteristics (such as age and gender) and residence matter in terms of multidimensional wellbeing. As expected, wellbeing decreases in old age following a non-linear trend, and women record lower outcomes too. Inhabitants of coastal provinces and urban citizens (provided they possess an urban hukou) have higher than average scores. The impact of these characteristics is not homogeneous across the distribution of wellbeing. • Heilongjiang province, an emblematic case of economic stagnation in the north-east, reports a significantly worsening well-being trend, significantly different from the remaining "pooled" data. On the contrary, the catching-up Guizhou province records faster growth in the multidimensional wellbeing index. After many years of outstanding GDP growth and structural changes, China is now facing an economic slowdown. This paper aims to analyse the effects of this slowdown on individual well-being, from a multidimensional and provincial perspective. The empirical analysis is based on data obtained from the China Health and Nutrition Survey, for the 2011 and 2015 waves. The notions of moderate prosperity, harmony and balanced growth pursued by the Chinese Government are used to select nine dimensions. These dimensions – based on 56 variables – are aggregated into an individual well-being index using the Multidimensional Synthesis of Indicators technique. The econometric results reveal that, in the 2011–2015 period, individual multidimensional well-being stagnated; moreover, some dimensions were affected much more than others, according to individual characteristics (e.g. age, gender) and geographical differences (e.g. urban/rural, east/west provinces). This creates new challenges for the central and provincial governments of China, in their pursuit of a more 'harmonious' and balanced development. [ABSTRACT FROM AUTHOR]

This paper mainly explores the deformation instability mechanism and influencing factors of landslide in a town called Fa'er, in southwestern China's Guizhou Province. Drawing on the theories of engineering geological mechanics, the exploration was carried out through the analysis of geological data, field investigation, and drone survey. The results show that: The mining of underground coal seams led to multiple tensile cracks on the trailing edge; the fragmented rock and soil mass, as well as the free face on the front edge create a favorable landform for initiating the landslide; the landslide is mainly induced by the heavy rainfall for several consecutive days; under the continuous heavy rainfall, the creep shear zone was penetrated by cracks, and the landslide was pulled by gravity to slide; the deformation mode shifted from creeping-tensile cracking to plastic flow-tensile cracking. [ABSTRACT FROM AUTHOR]

Research on the mineralogical and geochemical characteristics of altered end-Guadalupian basaltic volcanoclastic rocks can increase the understanding of the alteration history of the overlying stratabound Nb(Ta)-Zr(Hf)-REY-Ga mineralization in the Late Permian coal-bearing sequences. In this paper, based on petrographic observations in addition to XRD, XRF, and ICP-MS analyses, we present and discuss in detail the relationships between primary and secondary minerals and outline the distribution of major and trace element chemistry in the middle/Late Permian basaltic volcaniclastics from the ELIP's zone, western Guizhou, southwest China. The primary clastic suite consists of plagioclase-group minerals, clinopyroxenes, feldspathoids, spinels, and basaltic glasses. Fragments of mafic and, less commonly, felsic and alkaline volcanic rocks are minor components of the studied samples. The alteration products are represented by various chlorite-group minerals (including abundant chamosite), quartz, calcite, albite, analcime, barite, and pyrite, along with relatively minor amounts of titanite, sanidine, magnetite, rutile, and copiapite. The mineralogical and geochemical characteristics of the studied volcaniclastics provide strong evidence correlating them with the high-Ti basalt group, widely distributed within the inner Emeishan large igneous province (ELIP) and coeval rift zone of the middle and outer ELIP. After deposition, the volcaniclastics reacted with complex solutions including heated meteoric waters and were periodically infiltrated by seawater and ascending hydrothermal fluids. As a result, the primary volcanic rocks partly lost alkalis, titanium, silica, and most of the trace elements. These elements, especially the incompatible elements, were probably enriched in the overlying tuffaceous and coal-bearing sequences in the middle and outer ELIP. • Primary and secondary minerals of Emeishan basaltic volcaniclastics were presented. • The volcaniclastics reacted with complex solutions from various sources. • The primary volcanic partly lost alkalis, Ti, Si, and most of the trace elements. • The lost elements were probably enriched in the overlying sediments. [ABSTRACT FROM AUTHOR]

Organic-rich shale related uranium (U) mineralization has attracted widespread attention as a strategic and clean alternative to fossil energy and a paleoceanic redox proxy. A comprehensive study of mineralogy, organic geochemistry and elemental geochemistry of the lower Cambrian Niutitang Formation organic-rich shales in northeastern Guizhou, South China was conducted to address this issue. SEM-EDS results showed that the U occurrence state in the Niutitang Formation shales is dominated by nanoscale U minerals, mainly including coffinite, brannerite, U-bearing apatite and U-bearing xenotime. Various states of U are closely associated with organic matter, apatite, pyrite and clay minerals. Based on geochemical indexes, paleomarine condition and event deposition jointly drove the U enrichment in the Niutitang shales, in which hydrothermal activities and/or volcanic eruptions increased U fluxes in seawater and euxinic environment with high primary productivity provided a favorable condition for U reduction. The adsorption, complexation and reduction of UO 2 2+ by organic matter and the formation of uranyl phosphate complexes by the combination of phosphate and UO 2 2+ accelerated U immobilization and enrichment from bottom water to sediments. The microbial activities (e.g., BSR) in this process created favorable euxinic conditions and released inorganic-phase P to provide available ligands for UO 2 2+. The U enrichment models of the lower Cambrian Niutitang shales in northeastern Guizhou were established. This paper provides a new insight into the U enrichment mechanism in organic-rich shales, and may also have implications for the applicability of U as redox proxy and the exploration of organic-rich shale related U deposits. • The U occurrence states in Niutitang shales were studied through SEM-EDS. • Paleomarine condition and event deposition jointly drove the U enrichment. • Organic matter, phosphate and microbial participation accelerated the U enrichment. [ABSTRACT FROM AUTHOR]

With the acceleration of urbanization and industrialization, the land-use mode in mountainous areas has changed significantly, causing serious ecological destruction. Therefore, improving the efficiency of land-resource use in mountainous areas and enhancing ecological protection are important issues. This study focuses on typical mountainous areas in Guizhou Province to explore their significance not only for ecological restoration but also for sustainable socioeconomic development. In this study, we integrated the framework of the interaction between land-use transitions and landscape patterns and employed Spearman's rank correlation coefficient and a spatial bivariate model to reveal the spatiotemporal heterogeneity of landscape patterns and land-use transitions. The results showed that for 1990–2020, the cultivated, forest, and grassland areas decreased by −1353.66, −749.98 and − 541.72 km2 respectively, whereas the water area, urban, and other construction land increased by 799.69, 542.62, and 1230.90 km2, respectively. Moreover, the cultivated land areas converted into urban and other construction land were 358.03 and 661.77 km2 respectively, and the grassland areas converted into forest and other construction land were 3550.08 and 277.32 km2, respectively. Different land-use transitions presented rapid expansion and contraction characteristics, resulting in an increase in overall patch fragmentation, a decrease in uniformity, and an increase in irregular patches, which enhanced the spatial heterogeneity of diversity and complexity. Finally, the land-use transition effects on landscape patterns were primarily elevation, slope, and primary road facility factors. In-depth research on land-use transitional evolution and its impact on landscape patterns has important theoretical and practical value for formulating land-management policies and promoting sustainable development in mountainous areas. • This paper explores the relationship between land use and landscape pattern evolution based on natural and socioeconomic framework. • The process of land use transition has obvious influence on landscape pattern evolution. • Land use transition resulted in significant spatiotemporal heterogeneity of landscape pattern. • Land use management provides insights into landscape planning and ecological restoration. [ABSTRACT FROM AUTHOR]

Heavy metals (HMs) are often abnormally enriched in soils in geologically high background areas, posing a serious threat to the ecosystem and human health. However, the material origin of HMs in overlying soils is unclear. In this paper, we studied the accumulation control and formation process of HMs (Cd, Hg, As, Pb, Cr, Cu, Ni, and Zn) in soils overlying bedrock from different geological periods in a typical anticline structure area in southwest of Guizhou province. The results revealed that the content of HMs in the bedrock were ranked as Carboniferous carbonate rocks < Permian carbonate rocks < Triassic clastic rocks, while the opposite trend was observed for the HMs content in the overlying soil. The slopes of the EF-Q values of HMs in the soils overlying the Carboniferous, Permian, and Triassic rocks were 0.003, 0.007, and 0.83, respectively, which suggests that HMs enrichment or leaching was more complicated in the process of carbonate weathering soil-forming, whereas it was mainly in situ weathering during the process of clastic weathering soil-forming. The soils overlying the bedrock of the three geological periods experienced similar weathering processes and had the same source of soil-forming matrices, as it was observed that their Fe 2 O 3 -Al 2 O 3 , Hf-Zr, Nb-Ta, Th/Sc-Zr/Sc and Y/Ho-Y contents were significantly correlated (with R2 values of 0.80, 0.94, 0.72, 0.60, and 0.76, respectively) with very similar REE assignment patterns. The results corroborated the causes of the high background geological heterogeneity of HMs in the overlying soils in karst areas and supported the theory of the source of weathering soil-forming materials from carbonate rocks in karst areas. • Enrichment trends of HMs in soils overlying different geologic periods were opposite to those in bedrock. • Sources of HMs in soils of the study area are determined by both bedrock and anticline structure. • Leaching degree of HMs in carbonate rocks is greater than that in clastic rocks during soil-forming. • Accumulation of HMs in the soil is a residue of weathering of the in-situ bedrock and the limbs strata. [ABSTRACT FROM AUTHOR]

Abstract This paper describes an osmundalean stem from the Lopingian (upper Permian) Xuanwei Formation in eastern Yunnan Province, southwestern China. The stem of T. resinus sp. nov. is very small, only ca. 1 cm in diameter, and is characterised by the bi-zoned pith, pith cells typically vertically elongated, ectophloic siphonostele, primary xylem mesarch and 6–8 tracheid thick, a mass of sclerenchymatous cells in the adaxial concavity of the leaf trace and an arch-shaped secretory cell band surrounding the adaxial side of the leaf trace. The stem is compared with the member of Osmundales and is assigned into the genus Tiania of the extinct family Guaireaceae, where it represents the smallest member of the Guiariaceae. Distinctions from Tiania yunnanense include no sclerenchymatous and secretory cells in the primary xylem and the secretory cells in the cortex distributing around the adaxial side of the leaf trace and lead to the establishment of Tiania resinus sp. nov. T. resinus together with the three other species from three genera osmundalean trunk/stem have now been reported from the Upper Permian of eastern Yunnan and western Guizhou, southwestern China. Discovery of the new species enriches the diversity of osmundalean plants from the Cathaysian Flora and offers evidence that the area of eastern Yunnan and western Guizhou may be an centre for the distribution and the early evolution of extinct osmundalean family Guaireaceae. Highlights • This paper describes a new species of osmumdalean stem from Upper Permian of China. • The new species enrich the diversity of osmundalean plant of Cathaysian Flora. • The southwestern China is the center of distribution and early evolution of Guaireaceae. [ABSTRACT FROM AUTHOR]

Analyzing the causes of accidents, excavating accident paths, and applying accident prevention are important tasks in safety management. Focusing on coal and gas outburst accidents, this study examined the primary accident path and conducted applied research on the reasoning of the accident case. First, combined with the obtained accident causes, a coupling analysis of the causes of coal and gas outburst accidents was conducted. Second, using the method of data mining coupled with Apriori algorithm, the coupling relationship between each cause module of the coal and gas outburst accident was obtained, and consequently, a path map of the coal and gas outburst accident was drawn. Third, a Bayesian network model for the causes of coal and gas outburst accidents was established based on the accident path map and the probability of occurrence of each cause. Finally, considering the safety concept element (SC1) as an example, the Bayesian network model was used to conduct a sensitivity analysis of accident causes. Thereafter, considering the coal and gas outburst accident of the Sanjia Coal Mine in Guizhou Province as an example, probabilistic reasoning research on the cause of the accident was conducted. The application results showed that (1) under normal conditions, there are approximately 797,280 accident paths for coal and gas outbursts. Following data mining, 188 main accident paths were found. (2) Sensitivity analysis determined 19 factors that were sensitive to safety concept elements (SC1), of which the three most sensitive factors were (i) resource management system procedures (SM7), (ii) safety policy (SM1), and (iii) safety training system procedure (SM8). 13 paths exhibited a sensitivity ≥0.5%, of which 7 exhibited strong sensitivity. (3) The absolute accuracy rate of accident cause reasoning in the Sanjia Coal Mine in Guizhou Province was 71.43%, while the relative accuracy rate was close to 100%. Thus, it was concluded that: (1) the accident path mining method proposed in this paper is feasible for main accident path mining. (2) The Bayesian network model for the causes of coal and gas outburst accidents established in this study can be practically applied for the sensitivity analysis of accident causes and exhibits high reliability in the probabilistic reasoning of accident causes. The results of this study is expected to aid in the prevention of coal and gas outburst accidents, and provide reference and help for the path mining of other accident causes and the probabilistic reasoning of accident causes. [ABSTRACT FROM AUTHOR]

Denudation is a critical factor controlling the post-ore change and preservation of deposits, and the study of the degree of post-ore denudation is a common practice in mineral exploration. This paper introduces the use of singularity analysis and its efficacy in evaluating the degree of denudation of Carlin-type gold deposits in southwest Guizhou. The paper specifically focuses on investigating the geological effects before and after the introduction of the singularity analysis. Compared to the results obtained by means of the element concentration contrast, the results of the singularity analysis effectively estimate the relative degrees of denudation of the deposits and ore fields. In addition the results also accord well with findings from studies of the geology of ore deposits, the geochemical primary-halo and the apatite fission track. These outcomes suggest that using singularity analysis to determine the degree of denudation can yield significant geological information and support accurate interpretation of the data. Thus, the evaluation results based on such analysis have a higher reference value for expanding the understanding of post-ore deformation of deposits and exploring unexposed orebodies in southwest Guizhou. [ABSTRACT FROM AUTHOR]

Hydropower, an excellent power source for peak shaving, can respond quickly to load changes, which helps to overcome the anti-peak characteristics of wind and solar power. However, complementary operation with wind and solar power changes the operating boundaries of hydropower stations, making the original operating rules no longer applicable. Considering daily peak-shaving demands, this paper proposes a methodology to develop operating rules for a hydro–wind–solar hybrid system (HWSHS). First, a multi-objective and multi-timescale operation model is developed to ensure energy generation and peak-shaving performance simultaneously. Second, the feasible and reasonable region of available energy-based operating rules is analyzed, and three rule forms are employed to explore the optimal operating rules. Last, NSGA-II is utilized to optimize the rule parameters. A decoupling method is proposed to handle the shape constraints of operating rules, and the multi-timescale simulation method for a HWSHS is developed as the fitness function. In the simulation method, a load reconstruction-based load shedding (LRLS) method is introduced to determine the hourly output of each hydropower station. A forebay elevation check method is performed to obtain the hourly forebay elevation and correct the hourly output. The Beipan HWSHS in Guizhou Province, China, is selected as a case study, and the optimal operating rules are determined. The results also show that (1) the standard operating rules with hedging and packing increase peak-shaving performance by an average of 4.31% and 2.03% compared to the standard operating rules and linear operating rules, respectively; (2) the peak-shaving performance can be significantly increased (6.70%) with a slight decrease (0.37%) in the energy generation through changing the seasonal distribution of water and energy of the cascade hydropower stations; (3) the LRLS method, which makes the interday energy distribution more uniform, increases the peak-shaving performance by an average of 9.17% compared to the traditional load shedding method; (4) the energy generation and peak-shaving performance of the HWSHS are affected by the transmission capacity, and it is necessary to increase the transmission capacity by 25% to 35% of the installed capacity of wind and solar power stations. • A methodology is proposed to develop operating rules considering peak-shaving demands. • A multi-objective and multi-timescale operation model is developed. • The feasible and reasonable region of available energy-based operating rules is analyzed. • A multi-timescale simulation method is designed to simulate the operation of a HWSHS. • The methodology significantly improves the peak-shaving performance. [ABSTRACT FROM AUTHOR]

• A composite index named GLCDES is developed to dynamically assess the level of Green Low-carbon Circular Development. • The combined-assignment VIKOR model based on game theory is developed to thoroughly estimate the construction level of GLCDES. • Southwest China's Green Low-carbon Circular Development Economic System construction level is examined from 2012 to 2021, showing how the long-side principle governs each region's value. • Selecting and strengthening the long side in combination with its reality is an effective way to improve the construction level of GLCDES. Emission peak and carbon neutrality are critical components of China's overall ecological civilization, and the establishment of a sound Green Low-carbon Circular Development Economic System (GLCDES) is a fundamental countermeasure for solving China's resource, environmental, and ecological problems. This paper used the new development concept as entry points to establish a comprehensive evaluation index system encompassing six subsystems: development dynamics, production and living systems, green benefits, low-carbon benefits, circularity benefits and socio-economic benefits. The combined-assignment VIKOR model, based on game theory, was used to thoroughly estimate the construction level of GLCDES by combining panel data from four southwestern provinces, including Chongqing, Sichuan, Guizhou and Yunnan, from 2012 to 2021. The study discovered that: the construction level of GLCDES in all four southwestern provinces increased over the past ten years, but the increase was not significant, the four development effectiveness indices, including green, low-carbon, circularity and socio-economic, were significantly improved, the development dynamics index was not significantly enhanced, and the index of production and living systems declined in fluctuation from year to year. The construction level of GLCDES between regions was very uneven and can be divided into two echelons, with the gap between Chongqing and Guizhou being particularly obvious. Regions can be categorized into three major categories based on the number of dominant subsystems. According to the above results, the total value of the dynamic comprehensive evaluation of each region is governed by the principle of the long side, which is an effective way to improve the construction level of GLCDES by selecting and strengthening the long side in combination with its reality. [ABSTRACT FROM AUTHOR]

[Display omitted] • Metallogenic mechanism of lithium resource in sedimentary bauxite (aluminum) deposits was proposed. • Lithium associated with clay minerals in sedimentary bauxite (aluminum) deposits was concluded. • The occurrence states of lithium in clay minerals were reviewed. • The affecting factors of lithium leaching from clay minerals were discussed. Bauxite-associated type Li resource is mainly discovered in the sedimentary bauxite (aluminum) deposits forming areas, especially Northern Guizhou-Southern Chongqing, Western Henan and Central Guizhou, China. This paper reviews the enrichment mechanism and occurrence states of Li in sedimentary bauxite (aluminum) deposits. The Li in these deposits is derived from underlying carbonate rock, and the favorable sedimentary environment, e.g., alternation climate of dry and humid, the marine-continental transitional zone with reduction-weak oxidation and low salinity, is conducive to the Li enrichment in these deposits. Li is mainly hosted by independent mineral (i.e., cookeite), partly adsorbed by montmorillonite, and rarely adsorbed by illite/kaolinite. Furthermore, the leaching methods and affecting factors of Li from bauxite-associated type Li resource are summarized. Acid solution is the main leaching solution, but its excessive use can generate abundant acidic residues, which have hazards to the environment. Thereby, leaching solution with little or no acid has been recommended. The affecting factors of Li leaching are the calcination temperature, leaching temperature, leaching time, liquid–solid ration and mineral particle size. The above summary deepens the understanding of the enrichment mechanism and occurrence states of Li in the sedimentary bauxite (aluminum) deposits, and has the potential to promote Li resource, initially considered uneconomical, become an important economic source of Li. [ABSTRACT FROM AUTHOR]

Built vernacular heritage as a driving force for local development, its effective stewardship could contribute to the sustainability of heritage resource and local development. This paper assumes that stewardship of heritage resource as a more systematic approach engages with different interactive relationships and relevant behaviors between public and private sectors and aims to explore how the sectors interact in the process of stewarding heritage resource for local development in the context of rural society of China. This paper is designed as a double-staged qualitative field research. In first stage, non-participant observation is conducted in 35 southwestern villages located in Chongqing and Guizhou and then three stewardship models of heritage are figured out: top-down, expert-led, bottom-up. In second stage, three villages as exemplars are selected in the scope of observation and then unstructured interview is conducted there so as to give further explanation of how well the models functionalize in practice. Based on the analysis of data, this paper argues that in each model of stewardship the interactive behaviors of different sectors are hard fact to disentangle, that there exists a hybrid of steward-like and agent-like behavioral orientation in their interaction. In reference to the analysis on the pros and cons of each model, this paper proposes that it is reasonable to manage and organize heritage resource within a new top-down model being characterized by networked collaboration between different sectors, correspondingly some specific suggestions are given in order to strengthen positive interface between different sectors in this model. [ABSTRACT FROM AUTHOR]

Batik is a traditional handicraft of ethnic minorities in southwestern China's Guizhou province. It carries distinctive features, and inherits profound artistic and cultural values. However, the empirical design model of batik patterns is not fast or diverse enough to meet the highly personalized market demands. Moreover, it is difficult to parametrize the complex ethnic patterns with mathematical models. Hence, the design of batik patterns cannot satisfy the visual cognitive needs of consumers, which are constantly changing, fuzzy, and personalized. In other words, the visual cognitive needs of consumers have not been fully considered in the parametrization and design of batik patterns. To solve the problem, this paper puts forward a generative design method for batik patterns based on shape grammar, and relies on the artificial neural network (ANN) to model the nonlinear mapping between design parameters and visual cognitive image (VCI) values. The three-layer ANN model was optimized with the genetic algorithm (GA) to generate new patterns, and optimize the composition of their VCIs. The workflow and effectiveness of the proposed method were explained and verified through experiments on the generative design of bronze drum patterns, which have rich ethnic and religious connotations. The experimental results show that our method can predict the VCI values of the composition, provide the optimal parameter solution of the VCI values, and decompile the conceptual prototype from the pattern composition that best meets the visual cognitive needs of consumers. [ABSTRACT FROM AUTHOR]

• Seasonal variations of δ18O and δD in precipitation can be conserved in groundwater. • Amount-weighted isotopic input of rainfall affects seasonal amplitude of groundwater. • The seasonal isotopic strength conserved in groundwater varies with land cover. • Land cover impacts on evaporation loss and hydrodynamic conditions in groundwater. • To land cover, soil has the most important effect on dampening isotopic seasonality. δ18O and δD values in meteoric groundwaters reflect those in their source precipitation, which normally displays seasonal ranges of several to many permil. Normally there are substantial reductions in the groundwater isotopic ranges due to mixing in any vegetation, soil cover and the aquifer itself, plus the distortions that can be introduced by evaporation. Nevertheless, in carbonate karst regions (and others) many spring waters are found to preserve significant proportions of these seasonal signals. They are of current interest because they may also be detected in calcite speleothems precipitated from groundwater in caves, in calcretes and calcareous nodules in soils, etc. thus permitting detailed paleoclimate reconstructions. This paper presents some baseline data on reduction of isotope seasonal signals in groundwater that are pertinent to such speleothem studies. They are from artificial tank experiments at Shawan Karst Test Site, Guizhou, China. The climate is humid subtropical with mean annual precipitation of 1340 mm, >80% falling between May and October. The concrete tanks measure 20 × 5 m, 3 m deep each, point-drained at one end to simulate a spring. They are filled with 2.5 m of local limestone quarry gravel, creating carbonate aquifers with primary porosities ∼ 50%. A first tank is left bare, simulating the rocky desertification found in parts of the region. The other tanks are topped with 0.5 m of local, clay-rich residual soil, one left bare, the other three sown with rainy season corn, permanent grass and permanent shrubs respectively. Measurements cover the three climatic years, November 2015-November 2018. > 90% of the rainfall events were sampled, and the drains every ten days. δ18O and δD in the rainfall displayed strong and regular sinusoidal oscillations with the successive seasons. In the bare rock tank these were reduced (damped) by 56~74% in the different years, with phase (time) lags of 127~134 days at the drain. In the soil-topped tanks damping ranged from 61% to 93% and the time lags from 164 to 202 days: differences between them are not statistically significant but all do differ significantly from the bare rock. In all cases, the responses of the two isotopes were similar in direction and magnitude. The 0.5 m soil cover had the most important effect. The bare rock aquifer conserved the most information. Losses were similar in the four soil-topped tanks, responding to stronger evaporation and obstruction of flow in the soil. These findings are briefly compared to seasonal isotope variations reported in speleothem drip waters in limestone caves in China and elsewhere in the world. [ABSTRACT FROM AUTHOR]

Ensuring food quality and safety is essential after ensuring the quantity of food. Therefore, an improved adaptive particle swarm optimization algorithm (IAPSO) for optimizing the long short-term memory (LSTM) neural network (IAPSO-LSTM) is proposed to develop a food safety risk early warning model in this paper. The proposed IAPSO algorithm is verified by comparing with the traditional PSO (TPSO), the classic PSO (CPSO), the adaptive PSO (APSO) and the deterministic and adaptive PSO (DAPSO) based on five common benchmark functions in terms of the convergence speed and precision. Results show that the IAPSO algorithm has the best convergence speed and precision. Then, the analytic hierarchy process based on the sum product is used to obtain the risk value of food safety detection data, which is used as the desired output of the LSTM. And the root mean square error of the predicted risk value and the real food risk value is used as the objective function of the IAPSO algorithm to optimize the hyperparameters of the LSTM. Finally, the food safety risk early warning model based on the IAPSO-LSTM is evaluated using the composite seasoning detection data from a food testing agency in Guizhou Province, China. The proposed model effectively identifies high-risk factors affecting the risk value, with sodium cyclamate being the primary high-risk factor. The overall performance of the IAPSO-LSTM model is superior to that of the TPSO-based LSTM, the CPSO-based LSTM, the APSO-based LSTM, the DAPSO-based LSTM and the IAPSO-BP, with the prediction error of 0.474, R2 value of 0.998 and the absolute error less than 5. Moreover, the proposed model can help the relevant government departments effectively warn the potential food safety risks to ensure the food safety. [ABSTRACT FROM AUTHOR]

This paper presents the results of the geochemical and mineralogical investigation of siderite in the Late Permian coal-bearing strata from western Guizhou, SW China. Siderite occurs as fine-grained ooids, as recrystallized stellate-like forms, as ellipsoidal, rhombohedral, and oolitic aggregates, indicating their authigenic origin. In contrast, pore filling and veinlet siderite are of epigenetic origin. The low sulfur contents, absence of pyrite, and Sr/Ba ratios indicate that the siderite was deposited in a freshwater (non-marine) environment. The V/(V + Ni) values of studied samples, ranging from 0.68 to 0.86, indicate that the siderite developed under anoxic conditions. The presence of authigenic kaolinite and epigenetic siderite in the same samplesuggests that the chemical conditions changed from acidic to alkaline conditions during early diagenesis. Iron in the siderite was not only derived from silicate weathering of high-Ti basalts in the sediment source regions followed by transport as ions by ground and surface waters, but was also generated from in situ alteration of the Fe-bearing minerals within the peat itself. In addition, ascending hydrothermal solutions would also contribute some Fe, with the Fe probably sourced from the leaching of the basaltic basement. The presence of siderite-rich layers indicates enhanced chemical weathering rates in the sediment source regions. The δ 13C PDB , δ 18O PDB , and δ 18O SMOW values of siderite in claystones and mudstones vary within the ranges of −7.7 to 5.8‰, −12.1 to −6.6‰, and 18.4 to 24.1‰, respectively, indicating that carbon and oxygen primarily originated from marine carbonate, dehydroxylation of organic matter, carbonate dissolution, and hydrothermal fluids. The released CO 2 invoked the alteration of reactive silicate minerals in the sediments, and ultimately the formation of siderite. Circulating pore fluids dissolving iron, which is derived from the silicate weathering of high-Ti basalts in the sediment source regions and from in situ alteration of the Fe-bearing minerals within the peat, would transport some iron from the overlying peat into the underlying sediments, and the flow of fluids would be diminished or stopped at the base of the peat due to the mechanical barrier of the impervious claystone or mudstone layers. The ferrous iron was precipitated due to the alkaline environment conditions of the peat, by reaction with HCO 3 − dissolved in the waters to form siderite. [ABSTRACT FROM AUTHOR]

This paper takes environmental complexity to task by offering a way to understand the heterogeneity of an ecosystem in terms of its components’ relations rather than in terms of individuals (disaggregate) or wholes (aggregate). To do so, we use Escobar's notion of redes (networks) and Deleuze and Guatteria's ideas about human/environment relations as they relate to understanding the practical, political and emotional complexities of change in Fanjingshan National Nature Reserve (FNNR), Guizhou Province, China. A critical issue in the reserve relates to the resource-use relations between local farmers and an endangered snub-nosed monkey species, Rhinopithecus brelichi. Deleuze and Guattari point to understanding complexity through affective ecologies, while Escobar's work is particularly useful in connecting local activism, eco-tourism, and community networks in an attempt to contest globalized hegemonic discourses that do not necessarily support sustainability at the local level. The 21,000 farmers within FNNR have an intimate knowledge of their local environment that derives from day-to-day living and, for some farmers, from generations living in a particular area. The paper discusses some of the actions of local farmers that are variously connected to, and emotionally charged around, sustainability and the preservation of the snub-nosed monkey. [Copyright &y& Elsevier]

We conducted a series of core observation, thin section evaluation, and integrated with low-temperature nitrogen adsorption/desorption, porosity, permeability, breakthrough pressure analysis of the siderite-bearing strata. This paper aims to discuss the sealing capacity of siderite-bearing strata as a function of siderite abundance andmicromorphology type. The siderite-bearing strata can be potential gas barrier layers in multiply-superposed gas-bearing systems. In the transitional Lopingian coal-bearing succession of western Guizhou, the siderite content of siderite-bearing mudstone is 18.6–90.7% (wt.), with an average 53.4% (wt.). There are three morphologies of siderite, including S1 (gelatinous aggregates), S2 (microcrystal-silt size crystal aggregates), and S3 (sphaerosiderites). It shows that different abundance of siderite and type of siderite micromorphology affected the pore structure. The sealing capacity of siderite-bearing mudstone at the study area is somewhat or significantly larger, and the sealing capacity of the siderite-free mudstone is moderate. The development of siderite-bearing strata is controlled by the stratigraphy of the sequence. • Different siderite abundance and micromorphology type affected the pore structure. • The development of siderite-bearing strata is controlled by the sequence stratigraphy. • The siderite-bearing strata can be the potential gas barrier layers in multiply-superposed gas-bearing systems. [ABSTRACT FROM AUTHOR]

Poverty eradication is the primary goal of equitable and sustainable development and has received extensive attention from the international academic community. Rural land consolidation (RLC) is designed to achieve sustainable land use by combining land system reform and policy innovation; this has become an important means to promote China's poverty alleviation. From the perspective of micro-farmers, this paper takes the Sustainable Livelihood Approach (SLA) to reveal the influence of livelihood capital endowment on households' income growth and poverty alleviation under different modes of RLC. According to the survey data of registered poor households in four counties (cities) of Hubei Province and Guizhou Province, this paper uses fuzzy set qualitative comparative analysis (fsQCA) to empirically study several combinations of initial livelihood capital endowment after the implementation of different modes of RLC. The results show that RLC improves households' initial livelihood capital endowment, reduces the vulnerability of the livelihood, thus promoting the accumulation of households' livelihood capital and the optimization of livelihood strategies and urging households to obtain a sustainable livelihood, so as to contribute to poverty alleviation. Whether in the government-dominated mode area or Public-Private Partnership（PPP）mode area, the five types of livelihood capital endowments of households are interdependent and collectively affect income growth and poverty alleviation. However, the requirements for households' initial livelihood capital endowments are far lower after the implementation of PPP mode RLC than those after the implementation of government-dominated RLC. Based on these findings, this paper presents corresponding policy recommendations to improve the effectiveness of RLC poverty alleviation policy, and also provides China's experience and reference for other developing countries to formulate targeted antipoverty policies. • Use the Sustainable Livelihood Approach (SLA) to reveal the impact of livelihood capital endowment (LCE) on households' income growth and poverty alleviation under different rural land consolidation (RLC) modes. • Apply fsQCA to test characteristics and differences of initial LCE combination after implementation of different RLC modes. • Reveal that the dependence of households' income growth and poverty alleviation on initial LCE in PPP mode are far lower than government-dominated mode. [ABSTRACT FROM AUTHOR]

Humans have innately established close and profound ties with the, and through these relationships shaped many kinds of landscapes. Among these are sacred landscapes, which have drawn the attention of researchers due to their cultural significance. In the field of health geography, large-sized sacred regional landscapes are now the focus of studies for their therapeutic properties. However, few scholars have focused on small sacred landscape systems at the community level (constructed by local communities) or the physical and psycological health benefits that these landscapes offer to the local residents. These small-sized and widespread, but often hidden, sacred landscapes are closely tied to people's daily lives and work. They have evolved and grown over millennia to become critical sociocultural phenomena. This study takes the sacred bao ye landscape of the Dong people of China as the research subject. By adopting the case study approach, field research, semi-structured interviews, and textual analysis, it summarizes the types, geographical distribution, rituals and processes of bao ye as a sacred landscape of the Huanggang village in Guizhou Province, and concludes with an analysis of motivation and health benefits to the bao ye worship. In this paper we argue that bao ye is a sacred landscape system focusing on the healthy development of children, and constitutes a local belief developed in an isolated environment lacking medical resources, which remains in practice. The sacred landscape of bao ye offers a therapeutic environment, providing children with increased opportunities to engage with and build deep connections to nature. Thruogh this process children may develop a bond with nature that inspires them to protect nature on their own accord. We argue that bao ye offers an important case study for understanding the landscape-people-healing interactivity at the community level. • Sacred landscapes have beneficial effects on the physical and mental health of humans. • The community-level sacred landscape of Bao ye is important for the healthy development of local children. • The sacred landscape system of the Dong people helps to better protect this precious traditional cultural landscape. [ABSTRACT FROM AUTHOR]

[Display omitted] • A Givetian biostrome in Baoyang of southern Guizhou is documented for the first time. • The laminar stromatoporoid-dominated Baoyang Biostrome closely resembles the coeval Jiwozhai Reef. • The middle Givetian is an episode of landward extension of metazoan reefs in southern Guizhou. This paper presents a case study of shallow marine facies changes associated with reef development in the Middle Devonian of southern Guizhou. The sequence at Baoyang exhibits a close relationship between lithological and biotic changeovers in a nearshore belt, part of a sedimentary system on the southern margin of the Yangtze landmass. The Lower Devonian to middle Givetian siliciclastic-rich marine sediments inhibited carbonate deposition and reef-building communities until the combined effect of declining clastic supply and transgression allowed predominance of a carbonate platform and a newly reported biostrome, here termed the Baoyang Biostrome. The biostrome's principal constructors are two taxa of in situ stromatoporoids (Gerronostromaria and Salairella) of laminar form and whorled laminar form, and the branching Thamnopora , plus clay-rich carbonate matrix. Other, less abundant, constructors are taxa of five stromatoporoids, eight tabulate corals, five brachiopods, two rugose corals and one bryozoan. The Baoyang Biostrome is ecologically similar, in terms of biotic and lithological profiles, to the 30 km southeast, age-equivalent Jiwozhai Reef. The Baoyang Biostrome, Jiwozhai Reef and a further five Givetian reefs altogether indicate a pervasively landward extension of metazoan reefs on the Qian-Gui Carbonate Platform. Overall, the Middle Devonian sequences in Baoyang and other nearby localities are considered to represent a palaeoenvironmental turnover marked by reduced clastic supply and local transgression, changing the environment from tidal sandy nearshore to carbonate-dominated open marine platform settings. The local enhancement of reef-building accommodation in time and space matches the regional to global reef ecosystem expansion in the Middle Devonian time. [ABSTRACT FROM AUTHOR]

• A novel neural network with two residual blocks is proposed to improve the feature extraction ability of high-dimensional and redundant spectral data. Due to the high dimension of tobacco spectral data, a deep neural network is used to extract the features of spectral data. Two residual blocks are added into the proposed neural network to do identity mapping, which can map the data in a shallow layer to a deep layer. The identity mapping can effectively solve the issue of gradient disappearance that can increase the feature quantity of a deep neural network. • The balance and suppression factors are added to the loss function of the proposed neural networks, which solve the issue in training unevenly distributed data. The spectral data size of tobacco collected from different tobacco cultivation regions varies. In the training process of a neural network, the balance and suppression factors add more weight to small-size data samples. Therefore, the neural network can have the same classification ability for each data sample. • A parametric rectified linear unit (PReLU) function is used to add linear factors to the negative input, which can adaptively learn parameters in the network. In the network, batch normalization (BN) operation is used to speed up the network training and improve the generalization ability of the network. In addition, the exponential decay learning rate is applied to the control of learning speed. As a deep learning optimization method, dropout is used to avoid overfitting, improve the generalization performance of network, and make the model training converge faster. Near-infrared (NIR) spectroscopy techniques have been widely used to classify tobacco cultivation regions. NIR spectroscopy of tobacco leaves involves a large number of correlated features, so it is difficult to find the connection between spectral data and tobacco cultivation regions. This paper proposes a novel classification model of tobacco cultivation regions that integrates residual network (ResNet) and NIR spectroscopy techniques. As the number of neural network layers increases, the network may have issues such as network degradation, gradient disappearance, and the reduction of sample recognition rate. The proposed model applies a residual module to a neural network which effectively solves or alleviates the vanishing gradient issues caused by the increase of network depth. This paper also adds balance and suppression factors to the loss function to solve the issues caused by uneven sizes of tobacco samples collected from different cultivation regions in the training process. In the proposed method, tobacco samples are marked as internal and external samples respectively during the training process. Internal samples are collected from the corresponding cultivation regions in the north, northeast, and northwest of Guizhou Province, China. External samples are collected from other cultivation regions. The weight distributions of internal and external samples can be adjusted by experimental results to improve the identification accuracy of the proposed solution. The size of training samples determines the generalization ability of the network and affects the experimental results. A parametric rectified linear unit (PReLU) function is integrated into the network, in which the parameters of a linear unit are adaptively learned to further improve the identification accuracy of the proposed solution. Compared with current mainstream methods, the experimental results confirm that the proposed model is superior in accurately identifying different cultivation regions of tobacco leaves. [ABSTRACT FROM AUTHOR]

In northern Guizhou Province (Upper Yangtze Platform, South China Block) two types of reef communities developed in the Lower Silurian (upper Aeronian, Llandovery) Shihniulan Formation; they are calcimicrobial- and metazoan-dominated structures, and existed because of northward deepening of the shallow-marine ramp setting in which they grew. Stromatolitic communities are the focus of the present study and dominated the shallowest reef structures, while metazoan-dominated reefs, previously described in other papers, grew in the outer shelf portion of the ramp. Stromatolitic reefs occur in several sections (Daijiagou, Baishanxi, Jianba and Lianghekou), palaeogeographically close to Qianzhong Land. Within the stromatolite units, laminar sheets of microbial mats and columns are pronounced, with individual stromatolite thicknesses generally less than 1 m. Some very small stromatolites are only centimeters in diameter and thickness. Stromatolitic units are cyanobacterial bindstones mostly associated with shales, siltstones and thin-bedded bioclastic limestones. Their growth was frequently punctuated by siliciclastic sediments, and their shallow-water nature is demonstrated by association with birds-eye structures, cross-stratified sediments, and Lingulella -bearing silts in intertidal or/and lagoonal environments. The stromatolites formed during a regression and erosion surfaces are common at the top of the Shihniulan Formation. The Tongzi Uplift, a short-duration expansion of Qianzhong Land, ended the deposition of the late Aeronian limestones. [ABSTRACT FROM AUTHOR]

Bedded barite deposits are found in Cambrian and Devonian strata in China. In this paper, we report the occurrence of Late Paleozoic methane seeps from bedded barite in one of the largest barite deposits in China. The ore bodies are stratiform and lenticular in shape and are hosted within Upper Devonian cherts. The barite deposits usually have laminar, banded, fragmental, massive and rosette textures, and radial and spheroidal structures were observed in the barite ores. Nodular limestones are associated with the barite deposits; they consist of clotted micrites and framboidal pyrites. The internal structure of framboidal pyrite is simple, in which the sun-flower structure has been observed, similar to modern seep carbonates. The δ 13 C V-PDB values range from − 8.82‰ to − 10.27‰, and δ 18 O V-PDB ranges from − 8.10‰ to − 8.20‰ in Xiyahe and from + 0.03‰ to − 3.31‰ in Luocheng. The 13 C depletion suggests that these carbonates formed in a methane seep through the anaerobic oxidation of methane (AOM). This evidence lends strong support to the interpretation that methane hydrate contributed to the barite deposition. In addition, the δ 13 C V-PDB values decrease gradually from Xiyahe to Luocheng, which indicates the gradually weakening strength of the methane seep activities. The δ 30 Si NBS-28 values of the cherts range from − 0.3‰ to + 0.5‰, except for two samples (LJ-24: δ 30 Si NBS-28 values = + 0.9‰; ZL18: δ 30 Si NBS-28 values = + 1.1‰). The lowest δ 30 Si NBS-28 values reflect silicon derived from hydrothermal fluids ascribed to intense tectonic activity, which consequently caused the rapid maturity of hydrocarbons. The 87 Sr/ 86 Sr values ( 87 Sr/ 86 Sr = 0.70863–0.70898, avg. 0.70877; n = 11) of barite are higher than the average value of contemporary seawater, showing that hydrothermal processes played a minor role in barite mineralization. [ABSTRACT FROM AUTHOR]

• Organizing a panel data matrix from Pavement Management System in Guizhou Province. • Forming the method of establishing International Roughness Index prediction model. • Random-effects model of semi-rigid asphalt pavement in subtropical monsoon climate. • Considering the combined effects among age, climate, pavement structure and loads. • High accuracy and good robustness to the disturbances of region and climate. Pavement performance prediction is the crucial basis for decision-making of Pavement Management Systems (PMS). Pavement roughness is not only related to safety and comfort but also a vital index to evaluate highway performance. Therefore, it is of great significance to develop a prediction model for pavement roughness. The International Roughness Index (IRI) is the most commonly used index to represent pavement roughness in the worldwide. Many deterministic models based on time series data have been developed, but there are still few researches based on panel data to study IRI. This paper aims to investigate the rich information of panel data and develop a prediction model of IRI for semi-rigid asphalt pavements in subtropical monsoon climate. With the data from the PMS of Guizhou Province, the data matrix was built from 2017 to 2020. For the independent variables, the internal and external factors affecting IRI were considered, including climate, road age, traffic, and pavement structure. The random-effects model was employed for panel data analysis and the obtained model yielded a coefficient of determination (R2) value of 0.8858. This model can be applied to the highways which are designed, constructed, and qualified under the same standard and are located in the subtropical monsoon climate region. The predicted values in 2021 were compared with the measured values of highways in Guizhou Province. The average error is 12.7%. It shows that the model has better prediction accuracy and generalization performance with good robustness to the interference of geographic region and climate. [ABSTRACT FROM AUTHOR]

Recently, many types of coalbed methane (CBM) engineering practices have been applied in western Guizhou. However, most of these CBM practices (e.g., vertical well, horizontal well, cluster well.) have failed due to the complex geological conditions. To improve the success rate of CBM development projects, this paper proposes a CBM engineering mode selection method based on the geological conditions of the CBM resources found in western Guizhou. By analyzing the geology and considering the Upper Permian coal seams in western Guizhou as a case study, the geological conditions associated with CBM development were examined using measured data. In addition, the selective matching of existing CBM engineering methods to the geological conditions was examined and preliminarily demonstrated. The results indicated that the evolution of the geological conditions was primarily controlled by the vertical distribution of the coal strata, the hydrogeological conditions, and the tectonic stresses. The classification of the geological conditions into different types of CBM development geology was conducted according to the regional configuration of the geological parameters. A basic relationship exists between the type of geology and the engineering method for CBM development. To optimize the development engineering method and obtain high CBM production, the engineering methods of thin-layer staged fracturing of multiple coal seams, supplementary fracturing of sandstone reservoirs in coal deposits, and reservoir stimulation via protected coal seams during mining were preliminarily established. These methods represent a new direction for the CBM development of thin to moderate coal seams in western Guizhou. The technical feasibilities of the selected CBM development methods were verified by engineering practices, and certain CBM wells reported good production. This study describes the engineering effectiveness and adaptability of CBM engineering practices from the perspective of the development methods in the study area. In addition, this study emphasizes that the relationships between the geological conditions and the engineering methods might be broadly applicable when choosing the best CBM development engineering method for zones with multiple coalbeds in China. [ABSTRACT FROM AUTHOR]

The superposed reservoirs of coal-bearing series represent a new type of gas reservoir associated with coal seams, and those with multiple thin coal seams are an important subtype popular in Guizhou, an emerging area for coal-bearing series gas exploitation in China. So it is significance to accommodate hydraulic fracturing, a common stimulation technique for enhanced gas recovery from low permeability reservoirs, to the reservoirs there. Based on a number of engineering and test data from Songhe pilot project for coal seam gas recovery in Guizhou, this paper presents some effective stimulation techniques adapting to the superposed reservoirs of coal-bearing series with multiple thin coal seams, including drilling and well completion selection, gas-bearing intervals targeting, small-layer perforation, staged fracturing, ball sealer diversion and graded proppant injection. The study also focuses on the mechanism on adaptable hydraulic fracturing of the superposed reservoirs associated with multiple thin coal seams, by combining theoretical analyses and actual fracturing curve diagnoses. The results indicate that the fractures opening exhibit a certain temporal order depend on mechanical and other physical properties differences among individual perforated intervals, and the fracture opening sequence can be controlled by adjusting pumping scheme and dropping ball sealers; the fracture height extended into the adjacent rocks is a critical geometric parameter affecting scale of fracture network, and negatively correlated with tensile strength difference between coal seams and adjacent rocks; under a condition of the current maximum pump rate, the fracturing treatment in both multiple thin coal seams and interlayered sandstones have been implemented, and a fracture network has been generated with a uniform fracture geometry and strong flow conductivity by the combined application of the effective stimulation techniques. [ABSTRACT FROM AUTHOR]

This paper reports the mineralogical characteristics of a complete coal seam in the Late Permian Longtan Formation from the Yueliangtian mine, western Guizhou, southwestern China. The minerals in the coal were identified using optical microscopy, scanning electron microscopy with an energy dispersive X-ray spectrometer (SEM–EDS), and low temperature ashing plus X-ray diffraction (LTA + XRD). The results show that quartz and kaolinite are the major components of the coal mineral matter; followed by pyrite, marcasite, anatase, and calcite; and in some cases, mixed-layer illite/smectite, chamosite, illite, ankerite, apatite, and anorthite. The highly-elevated concentration of quartz in the coal is mostly derived from siliceous solutions produced by weathering of the Emeishan basalt. However, quartz discrete particles with large size (>100 μm) and rounded shape probably resulted from the input of felsic rock materials. The distribution and modes of occurrence of kaolinite, mixed-layer illite/smectite, illite, and anatase reflect a terrigenous origin. In comparison with the coals from eastern Yunnan, the Yueliangtian coals have lower proportion of authigenic chamosite, the formation of which was probably related to the injection of seawater. Pyrite occurring as individual particles or clustered framboids was most likely influenced by seawater during the stages of peat accumulation or early diagenesis, while fracture-filling pyrite probably had an epigenetic origin. Additionally, an intra-seam volcanic ash-derived tonstein layer, which contains sharp-edged quartz, vermicular kaolinite, and well-developed zircon crystals, has been identified in the coal of the present study. [ABSTRACT FROM AUTHOR]

Water security plays an important role in human sustainable development since the 21st century. This paper focuses on the water resource security in the karst areas of Guizhou province, China, to elucidate the stress mechanism and feedback relationship affecting water resource security sensitivity. Firstly, an assessment indicator system for water resource security is constructed with regard to the characteristics of water resources in the karst area. Secondly, according to the fuzzy mathematics theory, an assessment model for water resource security is constructed to dynamically evaluate water resource security in the karst area over a given time scale. Finally, to analyze the sensitivity and the stress mechanism of regional water resource security in the context of hydroclimate change, this paper establishes a system dynamics model, and sets four scenarios, namely, high flow year, normal flow year, partial dry year and dry year, to simulate and figure out the optimal scenario of regional water resource security. The results demonstrate that the integrated security of water resources in the karst area is highly sensitive in the context of hydroclimate change. In addition, the sensitivity of water resource security in the karst area would decrease from high flow year to dry year in the future. • Fuzzy mathematical and SD are used to measure water resource security. • From 2001 to 2015, water resource security eigenvalue increased from 2.03 to 4.65. • Water subsystems have diverse security sensitivity under hydroclimate change. • Water resource security sensitivity varies from dry year to high flow year. [ABSTRACT FROM AUTHOR]

Identifying coal texture has an important influence on the exploration and development of coalbed methane (CBM), but the prediction at the block scale is still insufficient. This paper combines the core idea of machine learning algorithm, coal body deformation mechanism, and critical layer theory to establish a prediction method for coal texture of CBM reservoir at block scale. The factor analysis method was used to eliminate the information redundancy of logging data, and the key logging parameters for identifying the coal texture were optimized. These include density (DEN), natural gamma ray (GR), X well diameter (CALX), and deep lateral resistivity (LLD). The K-means clustering algorithm was used to extract the numerical characteristics of crucial parameters. The K-nearest neighbor (KNN) classification algorithm established the identification equation of coal texture. The following classification was obtained: primary structural coal (T ≥ 0.70), broken-mylonite coal (T ≤ −0.50), and cataclastic coal (−0.50 < T < 0.70); these were used to accurately and finely divide the coal texture of multiple coal seams. Subsequently, from the fact that the structure of the coal body of a coal seam is necessarily influenced by the critical layers of the coal-bearing rock system in which it is located, the value of S for the strength of the coal-bearing rock system is proposed. According to the deformation characteristics of the coal body and the critical layer theory of the coal reservoir in the mining area, the length of the coal-bearing rock system section is determined as 30 m for the top plate and 20 m for the bottom plate of the coal seam and combined with the strength adjustment coefficient. The S value calculation is derived. The S value was calibrated using the calculation results of the coal texture logging identification model: primary structural coal (S ≥ 4.50), cataclastic coal (3.50 < S < 4.50), and broken-mylonite coal (S ≤ 3.5). Finally, the above methods are used to identify the block scale coal texture of the main coal seam of Kele syncline in western Guizhou. The identification prediction results are the same as those of underground sampling. • The strength value (S) of coal-bearing rock series and its calculation method are proposed.According to the deformation mechanism of coal and the theory of key strata, the strength S value of coal-bearing rock series is established and used to identify and predict the coal texturestructure. • The strength value (S) of coal-bearing rock series can be used to identify the coal texture. • The coal texture prediction method of the block scale CBM reservoir is constructed. [ABSTRACT FROM AUTHOR]

• Lulao catchment (LLC) is a small, homogeneous watershed on Guizhou Plateau, SW China. • Farmland soil (FS) has higher IRM 300mT /SIRM due to stronger pedogenesis in LLC. • Grassland soil (GS) has low IRM 300mT /SIRM & higher HIRM in LLC where a reservoir lies. • Contribution of FS vs GS to reservoir sediment is inferred with sediment's magnetism. • Changes in erosion is inferred as FS is distant from the reservoir than GS. This paper demonstrates that land use could enhance spatial discrimination of soil magnetism in a homogeneous watershed, and such differences help infer alterations in sediment sources and erosion. One sediment core was sampled from a reservoir built in 1958 and fifteen soil profiles from its catchment on the southern Guizhou Plateau, SW China. The whole watershed was covered by yellow earth developed on limestone. Magnetic measurements and granulometric analysis were performed on the soils and sediments while TOC and TN analysis on two soil profiles and 137Cs analysis on the sediment core. Information of seven years' land-use was derived from remote sensing images. The farmland and grassland soils had different magnetic characteristics while the downwards distributions of TOC and C/N were similar in the two profiles. The grassland soils had higher HIRM, lower χ fd % and IRM 300mT /SIRM. The higher χ fd % and IRM 300mT /SIRM of the farmland soils suggested stronger pedogenesis under cultivation. The average HIRM, χ fd % and IRM 300mT /SIRM were 38 and 334 10-6 A m2 kg−1, 5.7 and 3.6%, and 0.91 and 0.66 for the farmland and grassland soils. The farmland soils were finer probably due to tillage. The reservoir has been closely surrounded mainly by the grassland whereas the farmland, embedded with patches of the grassland, has occurred in the terrains relatively distant from the reservoir. The sediments of 1958–1985 had lower HIRM (156 10-6 A m2 kg−1) and higher IRM 300mT /SIRM (0.79), indicating greater contributions of the remote farmland soils mixed with grassland soils and stronger erosion. HIRM increased (229 10-6 A m2 kg−1) and IRM 300mT /SIRM decreased (0.67) in the sediments of 1985–2019, implying decreased distant-soil contributions and relatively increased input of the grassland soil closely around the reservoir. Erosion thus weakened, as proven by the finer sediments. The declining erosion was mainly due to farmland shrinkage and grassland expansion. [ABSTRACT FROM AUTHOR]

Based on the geological characteristics of hydrothermal fluid in the western Guizhou and eastern Yunnan regions, this paper discusses the geological mechanisms of hydrothermal fluid on the coalbed methane (CBM) system. From the perspective of hydrothermal fluid activity in the regional strata, we analyze the geological processes by which coalbed methane is enriched and accumulated in this region. Our results demonstrate that two stages of regional thermal fluid activity occurred in the western Guizhou and eastern Yunnan regions. In the earlier stage, calcium fluid acted as the carrier, but in the later stage, it was replaced by siliceous fluid with a small amount of calcium fluid. The former resulted from thermal cycling of fluid through the strata, and the latter was caused by injection of deeply sourced high temperature fluids. We propose three geological mechanisms by which hydrothermal fluid affected coalbed methane accumulation: stimulation for hydrocarbon generation, transformation for physical properties and fluid supercharging. The hydrothermal fluid impels coalbed methane to generate and migrate at high intensity; it also produces dense swarms of tubular pores that coincide with tectonic stress. As a result, the coal body is broken, and there are changes to the porosity and permeability of the coal. Pressure development in the regional gas reservoir depends on the intensity of the fluid effect and the differential leakage of fluid pressure in the coal reservoir. The relatively closed and stranded hydrothermal fluid environment of coal measure strata tends to lead to a high pressure coalbed methane system. The platform uplift in northwestern Guizhou is one such environment, in which the geological configuration of the high temperature fluid provided favorable conditions for the enrichment and accumulation of coalbed methane. [ABSTRACT FROM AUTHOR]

By means of the FISH language in the FLAC code, the coupled pore-fluid flow, heat transfer and mineralization have been simulated first with a generic model, and then with an actual geological model in the Caiyuanzi siderite ore district, Guizhou. The effect of pore-fluid pressure on the equilibrium concentration of siderite has been considered. The main purposes of this paper are: (1) to illustrate some simulation results for the possibility of hydrothermal mineralization of siderite in a sedimentary environment; (2) to get a better understanding of the processes and mechanism of siderite orebody formation in the sedimentary environment; (3) to analyze the influence of the concentration of carbon dioxide on the siderite mineralization; and (4) to compare the simulation results with the actual situation, so as to demonstrate that this simulation method is effective and feasible for understanding the mineralization mechanism of iron ore in the Caiyuanzi siderite ore district. [ABSTRACT FROM AUTHOR]

• An optimization algorithm for landscape index calculation is proposed. • The cutting effect and homogenization effect at different scales are identified. • The most suitable extent for landscape pattern research in Southwest China is 32 km × 32 km. • A suitable expression method of spatial heterogeneity is proposed. As the primary method used to describe landscape patterns, the landscape index method is widely applied throughout landscape ecology research, and the scale effect (grain size or extent) of the landscape index has continually been one of the important factors in landscape pattern research. Compared to research regarding the diversity of grain size, research regarding the scale effect resulting from the extent change has been given less attention; it should be given more. This paper applies patch density (PD) and splitting index (SPLIT), two main indicators of landscape fragmentation, to the 30-meter-grain land cover in Southwest China, and proposes an optimization algorithm to calculate the landscape index to explore the suitable extent and spatial expression of landscape fragmentation research. The results show that (1) the optimization algorithm of Fragstats, the landscape index calculation software, combined with R language and ArcGIS improves the software memory limitation, increases the calculation speed, expands the calculation range and simplifies the calculation process; (2) to avoid a calculation error resulting from the cutting effect and information loss caused by the homogenization effect, the most suitable extent of landscape pattern research in Southwest China is 32 km × 32 km；(3) clustering can characterize the spatial distribution of landscape indices, and spatial autocorrelation can characterize the differences within landscape indices, especially the aggregation relationship with adjacent landscape indices; combining these two can better show the regional fragmentation characteristics and internal correlations; and (4) based on the optimum extent of 32 km × 32 km, the landscape fragmentation in Southwest China could be studied. The results showed that the severely fragmented areas were concentrated in Guizhou Province, the border area between Yunnan Province and Guizhou Province, and the western part of Chongqing. SPLIT in Guizhou Province was mainly affected by population density; PD in Guangxi Zhuang Autonomous Region was mainly affected by annual precipitation; and PD in Sichuan Province was mainly affected by annual temperature and elevation. This study provides a more convenient and feasible method for comprehensively understanding regional landscape fragmentation and promoting the coupling analysis between landscape indices and other indices. [ABSTRACT FROM AUTHOR]

Shuiyindong is one of the largest and highest grade stratabound Carlin-type gold deposits in China. This paper reports on the results of petrographic studies, electron microprobe analyses (EMPA) of arsenian pyrite, and the mass transfer during mineralization and alteration, and it presents the deposit-scale distributions of Au, As, Sb, Hg, Tl, and trace elements in a representative cross section across the Shuiyindong Carlin-type gold deposit, Guizhou Province. The main objectives were to identify the precipitation mechanisms of minerals, or elements from fluids, and the migration paths of ore-forming fluids. Petrographic and EMPA studies indicate that gold in the primary ores is mainly hosted by arsenian pyrite. Mass transfer associated with alteration and mineralization shows that Au, As, Sb, Hg, Tl, and S were significantly added to all mineralized rocks, Fe 2 O 3 and SiO 2 were immobile in the main orebodies that are hosted in bioclastic limestone, and CaO, Na 2 O, Sr, and Li were removed from country rocks. The relations between Fe and S indicate that the sedimentary rocks at the Shuiyindong deposit contain more iron than is needed to combine with all of their contained sulfur to form pyrite. This suggests that sulfidation and decarbonation were the principal mechanism of gold precipitation at the Shuiyindong deposit. Hg, Sb, and As commonly formed sulfide minerals, such as stibnite, realgar, and orpiment, in late-stage quartz–calcite veins, or absorbed by organic matter in argillite. Fluid cooling presumably led to depositions of stibnite, realgar, and orpiment in late-stage quartz–calcite veins. Organic matter likely served as a reductant in argillite for the ore fluids, causing the precipitation of As, Sb, Hg, and S, as well as Au. Deposit-scale distributions of gold and other relevant elements reflect the passage of fluids through the rocks. Rock strata and structures allowed the ore-forming fluids to migrate horizontally along the unconformity surface of the Middle–Upper Permian, converge on the high position of an anticline, and then ascend into the overlying strata along the anticlinal axis. The distributions of the major and trace elements show that elements that accompanied the ore-forming fluids include Au, As, Sb, Hg, Tl, and S, and that Na 2 O and Li were exhausted in the Longtan Formation at the anticlinal core during gold mineralization. The enrichment of Co, Cr, and Ni in the Longtan Formation at the anticlinal core might be associated with deformation that formed the anticline, or with gold mineralization. Different host rocks were preferentially mineralized by different elements. The bioclastic limestone is commonly enriched in Au, whereas the argillite is preferentially enriched in As, Hg, Sb, and Tl. The zonation of ore-forming elements in the deposit appears to be Sb–Tl–As–Hg–Au–Hg–As (from bottom to top). Enrichment of Au, As, Sb, Hg, and Tl provides useful guidance for the exploration for Carlin-type gold deposits in Guizhou. Anomalies of As and Hg in soil or stream sediment might be an important clue and these elements can be used as indicator elements. Ore-forming fluids migrated along the unconformity surface of the Middle–Upper Permian and the anticlinal axis, so these are favorable sites for exploration for Carlin-type gold deposits in Guizhou. [ABSTRACT FROM AUTHOR]

• Floor heave failure of tunnel constructed in gentle inclined layered coal strata is investigated. • The principal causes of floor heave are clarified by field investigation and analysis. • The countermeasures for the floor heave controlling in related strata are proposed. • Floor heave failure of the tunnel is effectively controlled by the countermeasures, and safety construction in gentle inclined layered coal strata is achieved. Floor heaves threaten the safety of tunnels and pose major difficulties in tunnel engineering. This paper describes a case study on the floor heave mechanisms and corresponding control measures for highway tunnels in gently inclined coal seam in Guizhou Province, China. There are many factors behind floor heave in a highway tunnel, such as excavation method, high in-situ stress, weak rock, groundwater seepage, and quality of the floor. The displacement and stress of the tunnel were monitored during the tunnel construction to clearly illustrate the deformation, stress, and crack evolution characteristics. The stress in the tunnel structure indicated that horizontal stress was the main factor behind floor heave. It squeezed the layered coal rock mass along the beddings, causing fracturing of the rock mass under the floor. Meanwhile, water seeping through rocks further decreased the strength of the cracked rock mass. Subsequently, the failed rock mass squeezed the inverted arch upward. The secondary lining of concrete resulted in the inverted arch being subject to eccentric load, further causing buckling floor heave. Finally, the corresponding countermeasures were proposed and then verified by monitoring after implementation. The results of this study are significant for the optimization of tunnel design and can be used to ensure safety during construction in gently inclined coal seam. [ABSTRACT FROM AUTHOR]

As large-scale wind and solar power sharing hydropower transmission channels are put into operation in river basins to lower investment costs in China, joint operations of hydro-wind-solar energy sources have become an effective operating strategy in power systems. However, wind and solar output with uncertainties and volatilities are problematic and pose challenges for power grid optimal scheduling, especially for peak shaving of grid system. In this paper, a novel decision-making model based on the information gap decision theory method is formulated to optimize the complementary operation of multi-energy systems. First, with the objective of minimizing the variance of the residual load, a deterministic short-term peak shaving model for a hydro-wind-solar system as a base case is established. Then, to model uncertainties of wind and solar output in the hybrid system and analyze the impact of grid peak shaving, the risk averse and opportunity seeker strategies of information gap decision theory-based technique are developed. Finally, as a proficient multi-objective optimization method, the normalized normal constraint method is exploited to solve the information gap decision theory-based bilevel optimal problem, and a set of Pareto solutions is obtained for the decision maker. A hydro-wind-solar hybrid system in Guizhou Province in China, with seven hydropower plants, a virtual wind power plant and a virtual solar power plant, is taken as an example to demonstrate the effectiveness of the proposed model. The results indicate that, by considering the uncertainties of wind and solar output, the presented model not only reduces the load fluctuations but also increases the flexibility response to the system against operational risk. In addition, the calculation time and load variance of the system are greatly reduced in comparison with stochastic programming. • A hydro-wind-solar hybrid system alleviates the power grid fluctuation. • The IGDT method handles the uncertainties of wind and solar output. • The usage regions are found by robust averse and opportunity seeker strategies. • Impacts of uncertainty on the power grid peak shaving operations. [ABSTRACT FROM AUTHOR]

In comparison with the amount of study undertaken on the end-Permian mass extinction, the preceding Guadalupian mass extinction has received little investigation, even though it marks a significant biotic turnover associated with global environmental changes. During the earlier event, reef carbonate production shut down and was replaced by siliceous, mud-rich deposits (SRDs) in South China. However, changes in carbonate platform productivity during this epoch remain to be clarified. This paper presents sedimentological and conodont biostratigraphic investigations on the Guadalupian SRDs developed on the Yangtze Carbonate Platform (YCP) in central Guizhou. The findings are viewed in the context of Guadalupian sequence correlation of South China successions, which shows that the integrity of the YCP failed to match the platform tectonic evolution. The platform evolution saw the onset of major intra-platform depressions and the gradual onlap by SRDs along the platform margin. Stratigraphic correlation reveals that the platform experienced three phases of onlap by SRDs during the early Roadian, the late Wordian and the late Capitanian upwards. Platform carbonates re-expanded their extent following the first two phases, but not during the final phase. An evolutionary model is proposed for the Guadalupian carbonate platform, which follows the contemporaneous eustatic sea-level fluctuations. The partial drowning observed within the platform interior and increasing retreat along the platform margin could suggest an insufficient carbonate sediment supply shedding from the platform top during the Guadalupian. The variation in carbonate productivity raises our attention to the change in shallow-water carbonate factories, which is closely related to the fortunes of carbonate-secreting biota and environmental factors impacting the carbonate platform producers during the Guadalupian. [ABSTRACT FROM AUTHOR]

• The influence of stope roof structure movement on direct roof is expounded. • The mechanism of roof fall under repeated mining was studied. • Different instability conditions of cantilever beam structure are obtained. • Reasonable support working resistance is an important reason to maintain the stability of cantilever beam structure. In view of the problem that the broken stope roof under repeated mining is prone to end face roof leaks, this paper's research background is the close distance coal seams mining of a mine in Guizhou province, China. The impact of stope roof structure movement on the immediate roof was elucidated from the analysis of stope roof structure movement under repeated mining employing a combination method of field measurement, physical simulation, theoretical analysis, and numerical simulation. As a result, the mechanism of end face roof leaks under repeated mining is investigated, and the corresponding control measures are proposed. The results show that the cantilever beam structure instability of the stope roof under repeated mining is an important reason for the end face roof leaks and support crushing accident. The fracture forms of cantilever beam structure are divided into direct fracture and hinged structure fracture. The direct fracture is affected by the support working resistance. The cantilever beam hinged structure is divided into sliding and rotational instability. The periodic weighting interval is small and the fracture degree is large under repeated mining, which leads to the sliding instability. It is concluded that reasonable support working resistance is the important reason to keep the cantilever beam structure stability. Therefore, the stope roof leakage control countermeasures under repeated mining are proposed. The UDEC numerical simulation is used to verify the above analysis again, so as to provide the basis for the end face roof leaks prevention and control under repeated mining. [ABSTRACT FROM AUTHOR]

In addition to the major source of aluminum, karstic bauxite also contains high concentrations of trace elements such as Li, Ga, V, Sc, Co, Nb, Zr, Ni, U and REE. At present, more than 33.9 million tons of early Carboniferous bauxite overlies the karstic surface of the Cambrian carbonate rocks in Qingzhen region, central Guizhou, southwest China. Here, new mineralogical and geochemical evidence of the Lindai bauxite in Qingzhen region have been provided, aiming to identify parental affinity, discuss the provenance differences between the Qingzhen and Xiuwen areas, illustrate the mineral phase transformation, analyze the factors affecting the distribution of critical elements, and reveal the ore-forming process. Mineralogically, the bauxite ores are dominated by diaspore, boehmite, illite, kaolinite and anatase, with small amount of zircon, hematite, pyrite, cassiterite and medium-low temperature hydrothermal minerals such as barite, chalcopyrite, galena, arsenopyrite. Textural characteristics are dominated by matrix-supported clastic texture, followed by pseudo-breccias, recrystallizational and ooidal textures. Clastic grains with various sizes and shapes are often mixed together without obvious sorting and directional structures, indicating that bauxite ores have undergone short-distance transportation in the form of gravity flow. Provenance analysis indicates that the protoliths of the Lindai bauxite were a mixed lithology including underlying Cambrian Shilengshui Formation dolomite, hydromica claystone and purple-red mudstone rather than single dolomite considered by previous studies. Particularly, the presence of hydromica claystone and purple-red mudstone has a significant contribution to high concentrations of trace elements and REE in the Jiujialu Formation. Studies of mineral genesis have shown that the formation of diaspore includes supergene crystallization and metamorphism. R-mode factor analysis revealed that (i) these elements including Al, Ti, Ga and HFSE are relatively stable and immobile during weathering process, and tend to be enriched in the karstic bauxite, (ii) the distributions of HREE are controlled by the REE minerals and Fe oxide-hydroxides, (iii) vanadate minerals have crucial roles in the distribution of LREE in addition to the phosphate minerals, and (iv) the enrichment of Ni is related to the adsorption of hydroxo complex of uranium. The studies reported in this paper provide new insights into the provenance and mineral phase transformation of the Carboniferous karstic bauxite in central Guizhou area. [Display omitted] • The provenances of Lindai bauxite were mixed lithology rather than single dolomite. • The formation of diaspore includes supergene crystallization and metamorphism. • The Lindai bauxite contains high contents of critical trace and rare earth elements. • This study gives new insights into the genesis of karstic bauxite in central Guizhou. [ABSTRACT FROM AUTHOR]

[Display omitted] • The mineralized fluids are characterized by weakly acidic, reduced, and low temperature. • W/R interaction and CO 2 degassing caused the precipitation of carbonate minerals. • Mixing of metals and BSR-originated S2− resulted in the sulfide precipitation. • The origin of the Banbanjie deposit is similar to that of the MVT deposits. This paper investigates the origin of the newly discovered Devonian carbonate-hosted Banbianjie Ge-Zn deposit in South China. This deposit is rich in Ge (>900 t @ 110 ppm Ge) and contains 7.7 Mt of sulfide ores at a mean grade of 5.1 wt% Zn. The mineralization is stratabound or veined and is structurally controlled by the E-W trending Huangsi fault. Sulfide ores are dominated by sphalerite and dolomite with subsidiary pyrite, marcasite, and calcite, and minor galena. The mineralization forms massive, veined, brecciated, and disseminated structures and the hydrothermal minerals present in the deposit have colloform, fibrous, granular, and acicular textures. The hydrothermal dolomite has positive Ce (δCe = 1.13–1.20) and negative Eu (δEu = 0.43–0.68) anomalies that are indicative of formation in a weakly acidic, reduced, and low-temperature environment. The δ13C PDB and δ18O SMOW values of the dolomite range from −0.97‰ to −0.24‰ and +13.89‰ to +21.84‰, respectively, indicating that the dissolution of carbonate wall rocks was involved in the formation of hydrothermal dolomite. Theoretical C-O isotopic calculations further suggest that the hydrothermal dolomite formed as a result of water/rock (W/R) interaction and CO 2 degassing. The δ34S values of the sulfides (−11.23‰ to −4.95‰) are markedly lower than those of the Devonian seawater sulfate and sulfate from evaporates in the Devonian strata (+21.9‰ to +25.9‰), suggesting that the reduced sulfur was derived from evaporates within the ore-hosting sedimentary rocks by bacterial sulfate reduction (BSR). The Banbianjie sulfides have an upper crustal Pb isotopic affinity, as demonstrated by their 206Pb/204Pb (18.335–18.343), 207Pb/204Pb (15.725–15.735), and 208Pb/204Pb (38.288–38.326) ratios, suggesting the metals were derived from metamorphosed basement rocks. These data suggest that: i) the Banbianjie deposit formed as a result of a combination of weakly acidic, reduced, and epigenetic low temperature mineralized fluids, trap structures, and favorable lithologies; ii) W/R interaction and CO 2 degassing caused the precipitation of hydrothermal dolomite, whereas mixing of metals and S2− was the main formation mechanism of the sulfides; and iii) the Banbianjie Ge-Zn deposit is a typical Mississippi Valley-type (MVT) deposit. [ABSTRACT FROM AUTHOR]

• Two micro energy grid optimization models combined with regional energy characteristics are proposed. • An on-line adaptive optimization model and strategy for multiple MEG access to DN is proposed. • An effective measure of using distributed clean energy in mountainous area is provided. • The problem of various forms of energy supply in Southwest China has been solved. The rapid growth of distributed photovoltaic and wind power installed capacity in Southwest China has reduced the operation safety margin of the power grid. Power grid dispatchers face the dilemma of ensuring security of the power grid and the output curtailment of renewable energy. To achieve the full consumption of renewable energy, it is an effective way to make use of the space-time complementary characteristics of different energies by forming micro energy grids. By connecting to the distribution network, the energy among the micro energy grids can be transferred and distributed in the form of electricity. Therefore, this study builds collaborative operation optimisation models of distribution networks with multi-micro energy grids and proposes an adaptive dynamic real-time optimisation algorithm based on pre-training and online deep learning techniques for the joint system. A test system was constructed based on the actual equipment parameters and data from the Guizhou power grid. Through the calculation and simulation in the test system, the overload of the distribution network equipment and the network loss were effectively reduced while ensuring the full consumption of wind and photovoltaic power. In addition, the accuracy and effectiveness of the model and algorithm were verified. The results obtained in the case studies suggest that the method proposed in this paper can be applied to southwest China and similar regions. [ABSTRACT FROM AUTHOR]

• A Bayesian belief network (BBN) model is developed to determine the driving factors regarding trade-off changes. • The multi-scenario scheme of ES optimization is obtained by visualizing the key state of key variables. • Suggestions for ecological restoration were given, and a good way is to adjust the combination of the key state of key variables. The relationships between trade-off and synergy in ecosystem services (ESs) is essential for eco-environmental management and restoration in Karst regions, and many researchers have focused heavily on this. However, to date, and to the best of our knowledge, we still lack an adequate understanding of the driving factors of relationship changes and the optimization of the spatial pattern of ESs in this region. In this study, a Bayesian belief network (BBN) model was developed to link three major ESs—net primary productivity (NPP), water yield (WY), and soil conservation (SC)—and determine the driving factors regarding trade-off changes. Furthermore, the multi-scenario scheme of ES optimization was obtained and suggestions are provided in this paper for ecological restoration and decision-making in Guizhou Province, China. The results revealed that the relationships of regional ESs were mainly synergistic, but the synergistic relationship was weakening, accompanied by a trade-off trend during the study period. The area ratios with an enhancement of trade-offs in NPP and SC, SC and WY, and NPP and WY were 17.9%, 28.6%, and 26.6%, respectively, which indicates a significant uncoordinated changes between WY and the two other ESs. The ES relationships in this region are underpinned by multiple factors. Among them, water resources are the primary natural factor that restricts the concerted development of ESs, and the afforestation area (AA) is the main human factor that lowers the trade-offs among ESs. The superiority and distribution scope of ecological restoration were recognized through a multi-scenario analysis of the BBN model. In terms of the superiority of ecological restoration, it was concluded that scenario 3 > scenario 2 > scenario 1; in terms of the restoration area, it was scenario 1 > scenario 2 > scenario 3. Duyun City, in the south of Guizhou Province, as well as surrounding counties, were regions with a high probability of trade-off occurrences, and they could be regions for future ES optimization. Based on the driving factors and the occurrence probability of trade-offs, the ecological restoration area was identified, and it was found the ESs trade-off in this region can be decreased by adjusting a combination of the key variables' key states. This study provides insight towards achieving a mechanistic understanding and spatial expression of the driving forces underpinning trade-offs/synergies, in turn ensuring the accurate implementation of ecological restoration and the effective management of karst ecosystems. [ABSTRACT FROM AUTHOR]

• The whole safety production accidents of coal mines in Guizhou Province were analyzed. • The time–space dynamic evolution of coal and gas outburst accidents were proposed. • Coal and gas outburst accidents, influence factors and suggestions in Guizhou Province were studied. The safety situation of coal mines in Guizhou has been improving for many years, but coal and gas outburst accidents continue to occur. This paper analyzes the safety situation of coal mines in Guizhou by collecting data on accidents and disasters in the last decade: 2011–2020. The distribution characteristics, time–space dynamic evolution, and factors influencing coal and gas outburst disasters were studied. Countermeasures and safety management suggestions for disaster prevention and control were proposed. Our analysis shows that the primary disasters occurring in coal mines in Guizhou province are gas, roof, and water disasters, which are mainly distributed in the western and northern regions, as well as closely related to the complex geological conditions in the region. Coal and gas outburst is the most serious disaster threatening the safety of coal mines in Guizhou province in the last decade. The occurrence and development of gas outburst accidents presents three stages. The coal and gas outburst disasters mostly occurred in the driving face in the last decade, while their distribution showed obvious regional characteristics. In particular, Liupanshui, Bijie, and southwest Guizhou have a greater risk of coal and gas outbursts. Thus, it is necessary to focus on and formulate strict and effective outburst prevention measures when performing mining operations. Finally, according to hazard analysis, objective factors and management factors underlying coal mine disasters in Guizhou, specific countermeasures, and safety management policy suggestions of government and enterprises are provided. This research has certain significance for the safety supervision by the government and the staff engaged in the prevention and control of coal and gas outbursts. [ABSTRACT FROM AUTHOR]

Abstract: With the decoupling elasticity model, this paper studies the decoupling relationships (DRs) of total water uses (TWU) and provincial GDP, agricultural water uses (AWU) and agricultural added value (AAV), as well as industrial water uses (IWU) and industrial added value (IAV) respectively in Yunnan and Guizhou during the first ten years for the implementation of the Great Western Development Strategy. The results indicate that the DRs of water uses and economic development are highly undesirable in both provinces. Among the three groups, the DRs of AWU and AAV are the worst of all, with strong or weak coupling in 5 of the 10 years; the DRs of IWU and IAV are slightly better with strong coupling respectively in 3 of the 10 years in Yunnan and in 2 of the 10 years in Guizhou; and the DRs of TWU and GDP are the best, with strong or weak decoupling in 7 of the 10 years in both provinces. The DRs have improved in the period of 2006-2010 if compared with that in the period of 2001-2005. It is concluded that slow economic growth, low efficiency and poor structure of water uses are the main reasons for the worse status of DRs, and the development of economy and water uses efficiency promotes the DRs getting better. [Copyright &y& Elsevier]