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Currently, China is at a critical stage of economic transformation and pollution control. The environmental pollution control efficiency (PCE) deserves more in-depth study. This paper adopts a three-stage global data envelopment analysis (DEA) model and a global Malmquist index model to measure the PCE and the sources of its changes in China from 1991 to 2019. Study shows that: (1) the overall level of PCE has remained low over the past 29 years, and it has a slowly fluctuating upward trend, with an average annual growth rate of only 0.92 %; (2) the lower pure technical efficiency hinders the effectiveness of environmental pollution control, which is mainly affected by the slow technological progress; and (3) at the provincial level, the overall efficiency of Shanghai and Guangxi has long been above 0.9, while the efficiency of other provinces has been below 0.9 for quite a long time. At the regional level, the Yangtze River Delta is the most effective area, while the Yellow River Basin is the most ineffective area. In consideration of this, we provide specific strategies for improving PCE of each province, from three aspects of increasing the capital input, optimizing the scale structure, and upgrading technology level. [Display omitted] [ABSTRACT FROM AUTHOR]

Site selection is a key factor to the success of ocean thermal energy conversion (OTEC) project. It is a multi-criteria decision making (MCDM) problem with a series of conflicting criteria involved. However, limited studies were found concerning this area and problems existing in classical MCDM methods tended to fail OTEC site selection decisions. Therefore, this paper proposes an extended MCDM method and establishes a new decision-making framework to select the optimal location. First, a comprehensive evaluation criteria system for OTEC site selection from the view of sustainability with 16 criteria involved is established. Second, feasible alternative sites for OTEC project are identified by PEST analysis. Third, an extended PROMETHEE (Preference Ranking Organization Method for Enrichment Evaluation) under intuitionistic fuzzy environment is proposed to avoid compensation assumptions. During the decision process, seven groups of experts shared the work and cooperated with each other according to their backgrounds. Finally, a real case is studied and sensitive analysis is conducted, demonstrating the robustness and effectiveness of the proposed method. This study can effectively improve OTEC site selection decision making quality and also extends the domains of intuitionistic fuzzy PROMETHEE applications. • A novel multi-criteria decision-making framework for site selection is proposed. • The criteria system for ocean thermal energy conversion site selection is constructed. • A case study is carried out in areas of Guangdong and Guangxi Provinces in China. [ABSTRACT FROM AUTHOR]

• Mechanism of high frequency harmonic resonance of Luxi VSC-HVDC project is analyzed. • Time delay and system impedance will influence the high frequency harmonic resonance. • A method to suppress the high frequency harmonic resonance is proposed. This paper introduces the basic situation of high frequency harmonic resonance in Guangxi on April 10, 2017, which is based on the Luxi back-to-back voltage source converter based high voltage direct current transmission (VSC-HVDC) project in China. Firstly, the harmonic amplification mechanism and its key links in the event are analyzed in detail and verified by simulation. Secondly, the relationship among high frequency harmonic resonance, voltage feedforward control loop and system harmonic impedance is obtained, and the formulas among voltage feedforward control parameters, system harmonic impedance and high frequency harmonic resonance frequency amplitude are deduced. Then, a method to suppress high frequency harmonic resonance by adding a reasonably filter to the voltage feedforward control loop is proposed. Finally, the effectiveness of the proposed method in this paper is verified by simulation and field operation. [ABSTRACT FROM AUTHOR]

Mineral resource extraction is often accompanied by severe environmental pollution and ecological damage, hindering mining economies from achieving sustainable development. This paper aims to promote the goal of cleaner production in extractive industries from the perspective of environmental management through a more accurate understanding of how human activities affect the extractive industries. This requires more granular data for environmental damage in mining. The article proposes an ecological threat assessment framework for mining to support sustainable processes in the extractive industry. It integrates biophysical variables, technical indicators, and human activity data. The study is based on data at the mine level with 17 indicators used to evaluate the ecological impact of 13960 mines in Guangxi, China, from 2008-to 2018 in four dimensions: economic and technical indicators of mines themselves, surrounding economic activity, geological and environmental vulnerability, and ecological status of mining sites. Data from multiple sources were used to assess, map, and monitor ecological impacts in mining areas, such as high-resolution satellite images, interview data, environmental assessment reports, and mining rights data. We evaluated the ecological impact level of each mine and the extent to which spatial heterogeneity of regional economic and environmental preferences affected the degree of ecological impact. The results show that growth in population income has changed environmental preferences and driven down environmental disturbances in mines. Reduced dependence of regional economies on the industrial sector has also contributed to environmental improvements. In addition, increasing environmental regulation has limited the ecological impacts of mining, but these environmental regulation impacts are regionally heterogeneous. The effect of laws and rules is lower in cities and regions dependent on mineral resources, where resource extraction companies have more bargaining power. The results of this study will inform environmental management in the mining sector and support sustainable development in the region. [Display omitted] [ABSTRACT FROM AUTHOR]

The defected kaolinite is common in sedimentary kaolin, but its structure and disorder mechanism remains unclear. In this paper, three different size distributions of kaolinite particles: 0–300 nm, 200–1000 nm, and 500–2000 nm, were separated and classified from high-defect sedimentary kaolin, collected from Quaternary sedimentary kaolin in Guangxi Zhuang Autonomous Region of China. The three particle sizes of kaolinite have been monitored by particle size analyzer, high-resolution magic-angle spinning NMR (MAS NMR), small and wide-angle X-ray scattering (SAXS and WAXS), X-ray diffraction (XRD), BET surface analyzer, nitrogen gas-adsorption, scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM). The results revealed that the smallest particle size of kaolinite exhibited high degrees of broken Al-O-Al and Si-O-Si bonds, more disordered structure, and elevated specific surface area. The degree of the structural disorder of kaolinite increases as the particle size decreases, which can be attributed to the more aluminum substituted for silicon in tetrahedron sheet in the finer kaolinite crystal, compared to the coarser kaolinite crystals. • Kaolinite particles were separated into three parts, <300 nm, 200–1000 nm, and 500–2000 nm. • The degree of the disorder increases as the kaolinite particle size decreases. • The smallest particle size of kaolinite showed high degrees of broken Al-O-Al and Si-O-Si bonds. [ABSTRACT FROM AUTHOR]

[Display omitted] • Trace elements in sphalerite and pyrite distributed in the form of solid solutions or micro-inclusions. • The mineralization in the Beishan Pb-Zn ore district was under a low-temperature condition. • The Pb-Zn deposits in the Beishan Pb-Zn ore district are MVT deposits. The Beishan Pb-Zn ore district, located in northern Guangxi, China, is a giant carbonate-hosted Pb-Zn ore district. In-situ trace element analysis was performed using LA-ICP-MS on sphalerite and pyrite from three representative Pb-Zn deposits in the Beishan Pb-Zn ore district. The analysis of these trace elements reveals the trace element compositions of the sulfides, the distributions and the substitution mechanisms of trace elements, physicochemical characteristics of the ore-forming fluids, and ore genesis. Sphalerite is enriched in Mn, Fe, Ge, and Cd, while it is poor in Co, Ni, Ga, As, In. Pyrite is enriched in Co, Ni, As, Tl, Sb, and Pb, but poor in Mn, Ga, Ge, Cd, In, Sn. Mn, Fe, Cd, Ga, Ge, Sb, Ag, and As in sphalerite enter the mineral lattice mainly by simple or coupled substitution mechanisms, while Cu and Pb can enter the mineral lattice in the form of solid solution or micro-inclusions. Mn, Co, Ni, As, Tl, and Sb in pyrite substituted Fe2+ by simple or coupled mechanisms, while Pb can enter the mineral lattice in the form of solid solution or micro-inclusions. Studies of trace elements related to temperature (e.g., Mn, Fe, Ga, Ge, In) in sphalerite and pyrite indicated that mineralization in the Beishan Pb-Zn ore district occurred under a low-temperature condition. And according to the sphalerite GGIMFis geothermometer, the mineralization temperature of the Beishan Pb-Zn ore district was 55–268 °C (average 153 °C), of which 110–230 °C(average 153 °C) in Duchuan, 92–268 °C (average 149 °C) in Beishan, and 55–243 °C (average 167 °C) in Dongyong. The Mn, Fe, Ga, Ge, and In contents of sphalerite are similar to those of MVT deposits. The combination of some binary pattern diagrams, principal component analysis (PCA), and Co/Ni ratios of pyrite, with the geological features and physicochemical properties of the ore-forming fluids, indicates that the Beishan Pb-Zn ore district is an MVT district. This paper, combined with previous studies, shows that the Co/Ni ratio of pyrite has some guiding significance for mineral exploration of this kind of Pb-Zn deposit, with Co/Ni values around 0.1 indicating that the deposit has a better prospect of developing into a large deposit, and Co/Ni much less than 0.1 indicating that the deposit may not have a good prospect. [ABSTRACT FROM AUTHOR]

This paper reports the discovery of a new mammalian assemblage at Mocun cave in 2000 by the Natural History Museum of Guangxi. The Mocun site is located in a residual karst peak in southwest Guangxi, south China. Abundant mammalian fossil teeth and bones were extracted from relatively thick deposits, well constrained stratigraphically. The results show that 1) the Mocun fauna is composed of typical species of the " Ailuropoda - Stegodon association", including Stegodon, Ailuropoda, Rhinoceros, Pongo, Tapiru s, Megatapirus, and Elephas, common in the Middle to the Late Pleistocene, with a larger portion of modern species; 2) By employing U-series dating (MC-ICP-MS) method on both the soda straw stalactites and mammalian teeth collected from deposits, the age of the Mocun fauna has been constrained between 66 and 101 ka, a transitional period from the interglacial stage MIS5 to the beginning of the last glacial stage (MIS4), representing one of the securely dated Late Pleistocene sites in southern China so far; 3) The composition in large mammals suggests a forested environment which harboured a great biodiversity in large species; 4) The taphonomic analysis indicates that the fossil accumulation is mainly due to activities of porcupines and to water flows; 5) Interestingly, our taxonomic study reveals some changes in the occurrence of Tapirus sinensis and Megatapirus augustus between ∼66 and ∼86 Ka, along with a change in the abundance of artiodactyls versus primates. It remains to demonstrate with more comprehensive records if these changes may be related to the mid-Late Pleistocene climatic transition. • a new mammalian fauna cave site (Mocun cave) with accurate date to 66 and 101 ka in southwest Guangxi. • The composition in large mammals suggests a compatible habitat for a great biodiversity of species. • Some changes between layers with Tapirus sinensis replaced by Megatapirus augustus between ∼66 and ∼86 Ka, along with a change in the abundance of artiodactyls versus primates. [ABSTRACT FROM AUTHOR]

Within the cultural context of "guanxi" in China, it is particularly challenging to develop a framework capable to capture the complexity and adaptability of farmers facing conflicts between wetland conservation and livelihood development. In this paper, we integrate agent-based model (ABM) and field experimental methods to develop a hybrid simulation experiment model for wetland conservation behavior, in order to reveal the driving forces of land change and understand the dynamic change process of farmers' behavior. Through a field experiment and a questionnaire survey of farmers around the Shankou Mangrove Ecological Nature Reserve (SMENR) in Guangxi, China, the intention of different types of farmers to adopt wetland conservation behavior was assessed from different angles, constructing a rational choice theory (RCT) framework and ABM proxy behavior rules. The results showed that after 5 years, the adoption rate of farmers' wetland conservation behavior reached 100% under the assumption of bounded self-interest, but only about 80% under bounded rationality. This confirms that herd is more conducive to promoting farmers' wetland conservation behavior. Decision makers should consider the importance of bounded rationality and bounded self-interest interaction, foster farmers' sense of belonging and responsibility toward wetlands, and guide farmers to participate in the ecological protection and sustainable use of wetlands. [Display omitted] • Herd is more conducive to promoting farmers to protect wetlands. • The fastest take-off can be achieved at a threshold of about 20%. • Livelihood patterns lead to differences in willingness to protect wetlands. • Sense of belonging and responsibility is important for wetland conservation. • Combining experimental economics and ABM can improve the accuracy of the model. [ABSTRACT FROM AUTHOR]

Spatial regulation produces different advantages in areas with different land resource endowments. It also affects the welfare of stakeholders in different regions. Existing studies mainly focus on the "visible" welfare "windfalls" and "wipeouts" caused by spatial regulation, yet pay little attention on the "invisible" effects. This article selects Tianyang County (a key development zone) and Tiandong County (a restricted development zone) as its principal research areas. These areas have been divided as part of China's major function oriented zone (MFOZ) planning. The MFOZ represents the most significant and broad exercise in spatial regulation. These regions located in Baise City, Guangxi Zhuang Autonomous Region, China. After applying Sen's feasibility capability theory as the foundation on which to build a theoretical framework, this article calculates and compares the changes in farmers' welfare before and after losing land in the key development zones (weak spatial regulation) and the restricted development zones (strong spatial regulation) by using a fuzzy mathematics method. The impact of spatial regulation on the "invisible" welfare of land-lost farmers is then analyzed. The results show that: (1) differences in spatial regulation produce "windfalls" in the total welfare of land-lost farmers in the key development zones, but "wipeouts" in the restricted development zones; (2) the "visible" welfare of economic income for land-lost farmers are "windfalls" in the key development zones, but are "wipeouts" in the restricted development zones; (3) the "invisible" welfares of social security, development opportunities, living conditions and psychological conditions are "windfalls" for land-lost farmers in the key development zones, but are "wipeouts" in the restricted development zones; (4) the "invisible" welfare of living environments for land-lost farmers are "wipeouts" in the key development zones, but are "windfalls" in the restricted development zones. This study thereby provides evidence-based insights which can enable countries to formulate spatial regulation systems that promote balanced development among regions, and to fully consider the "invisible" welfare compensation of land-lost farmers as part of land expropriation compensation policies. • This paper applies Sen's feasibility capability theory as the foundation on which to build a theoretical framework, and calculates and compares the changes in farmers' welfare before and after losing land in the key development zones (weak spatial regulation) and the restricted development zones (strong spatial regulation) by using a fuzzy mathematics method. The impact of spatial regulation on the "invisible" welfare of land-lost farmers is then analyzed. • This paper makes the following two contributions. Firstly, there is no prior research on the "invisible" welfare "windfalls" and "wipeouts" caused by spatial regulation. This paper reveals that spatial regulation not only directly affects the "visible" welfare, in terms of the economic income, of land-lost farmers, but also indirectly affects their "invisible" welfare. Therefore, this article aims to enrich research on the direct and indirect multi-dimensional welfare impact of spatial regulation on stakeholders. Secondly, the current welfare compensation policies for land-lost farmers formulated in different areas of spatial regulation do not fully take into account the issue of invisible multi-dimensional welfare compensation, such as social security, development opportunities, living conditions, living environment, and psychological conditions. The research underlying this paper can therefore provide valuable data and insights which can help countries to formulate a spatial regulation system that will promote balanced development among regions, and can also provide a reference point for governments to improve welfare compensation policies for land-lost farmers by including invisible multi-dimensional welfare compensation. [ABSTRACT FROM AUTHOR]

Clean Development Mechanism (CDM) forest projects are perceived as an attractive way to both help mitigate climate change and transfer income to rural poor. However, to engender participation of small-scale producers, a CDM forest project must offer sufficient incentives, while minimizing their costs of participation, all the while respecting the need for additionality. Property rights, social capital and contractual rules are critical in the success of CDM forest projects. In this paper, we ask what factors affect participation in the world's first CDM project, established in Guangxi Province, China. Using village-level surveys, we find that although the project facilitates participation through carbon pooling and a share-holding system, much of the project land remains unforested. We find that the primary reasons for the unforested regions are constrained contractual rules, property rights allocation disputes and low levels of social capital in some villages. [Copyright &y& Elsevier]

Abstract: The Liucheng Gigantopithecus Cave is very famous for its rich mammalian fauna and Gigantopithecus fossils. The Gigantopithecus Cave Fauna has been regarded as the typical Early Pleistocene fauna in South China. The majority of the fossils unearthed has been studied and published during the past decades. The only group remaining unpublished is the rhinoceros, which is studied in this paper. The rhino materials available today are only mandibles and lower cheek teeth. The dimensions of the tooth rows and the isolated teeth fall well within the range of the recent Dicerorhinus sumatrensis. Therefore, the rhino fossils from the Liucheng Gigantopithecus Cave can be referred to this living species. The reduced lower incisors and the U-shaped lingual contour of the mandible also support this taxonomic determination. The rhino materials from the Liucheng Gigantopithecus Cave represent the earliest known record of this species and the smallest Pleistocene rhinocerotid in China. [Copyright &y& Elsevier]

Photovoltaic poverty alleviation project (PPAP) is initiated to reduce rural poverty and pursue cleaner production, but the lack of reasonable sustainability evaluation has become a challenge. This study evaluates the sustainability of PPAP in order to improve the poverty alleviation performance and efficiency considering an integrated multi-criteria decision-making (MCDM) method combining benefits, opportunities, costs, risks (BOCR) theory, analytic hierarchy process (AHP), interval type-2 fuzzy numbers (IT2FNs), and technique for order preference by similarity to an ideal solution (TOPSIS). First of all, this paper identifies 16 criteria based on BOCR theory from the perspectives of benefits, opportunities, costs, risks and constructs the criteria system. Second, an integrated BOCR-AHP-IT2FTOPSIS method is proposed and applied in processing ambiguous information and comprehensive sustainability evaluation. Third, an empirical case in Guangxi Zhuang Autonomous Region of China, a comparative analysis and a sensitivity analysis are used to rank the alternative PPAPs and verify the effectiveness and robustness of proposed method. The results show that the integrated MCDM method is capable to evaluate and rank the sustainability levels of PPAPs with the contribution of BOCR theory-based criteria system. The work offers a novel sustainability evaluation angle for PPAPs and has potential applications in providing understandings and making decisions. [ABSTRACT FROM AUTHOR]

Karst environments are globally significant, and the soils that develop on these landscapes often have unique geochemical features, including elevated–levels of metals. However, it has not been determined whether the enrichment of metals in soils is mainly controlled by parent rocks or secondary enrichment during weathering. In this paper, we studied the control of the accumulation of heavy metals in soils by parent materials and/or the process of soil formation. We examined the un–weathered carbonate and clastic bedrocks, as well as surface soils in a typical karst area in Guangxi of China. The spatial distribution of heavy metal (Cd, As, Cr, Cu, Hg, Ni, Pb, and Zn) concentrations in soils was mainly controlled by the geological background. Except for Cd, the concentrations of heavy metals in carbonate rocks were much lower than those in clastic rocks, whereas the soils derived from the carbonate rocks were highly enriched with heavy metals than those in clastic area. The enrichment of Cd in surface soils from the carbonate substrates was the result of the dual effect of secondary enrichment and parent rock inheritance, whereas the enrichment of other metals was mainly the result of secondary enrichment. During the weathering process of carbonate bedrock, great majority of the quantities of inherent heavy metals were leached, with only 2% of Cd being retained in situ. The high concentrations of soil Fe, Al, and Mn oxides, organic carbon and clay content (Al 2 O 3 /SiO 2) were closely related to the enrichment of heavy metals in studied surface soils. • Geological background controlled spatial distribution of soil metal concentrations. • Secondary enrichment and bedrock inheritance caused Cd enrichment in karstic soil. • Secondary enrichment caused the other metal (As, Cr, Cu, Hg, Ni, Pb, and Zn) enrichment in karstic soil. • 2% of Cd being retained in situ during the weathering of carbonate bedrock. • Soil Fe/Al/Mn oxides, organic carbon and clay content controlled metal accumulation in soils. [ABSTRACT FROM AUTHOR]

Being located between Eurasia continent and the western Pacific Ocean, the coastal area of China (hereafter as CAC) is vulnerable to climate change and prone to climate-related disasters. Based on the daily meteorological dataset of 156 stations, variations of consecutive dry days (CDD) and consecutive wet days (CWD) and their relationships with local and remote climate drivers from 1961 to 2017 over CAC were investigated. Results showed that the multi-year averages in CDD and CWD were 22.5–93.7 and 3.4–11.8 days, generally presenting a "high north and low south" and "low north and high south" spatial pattern, respectively. The decadal trend rates in CDD and CWD were − 4.5–2.7 and − 0.7–0.6 days per decade, respectively, both showing universal insignificant change trends over CAC. There was a significant negatively correlation between CDD and precipitation at partial of meteorological stations clustered in Guangxi autonomous region, and a predominantly significant positive relationship between CWD and precipitation over CAC. Both CDD and CWD correlated significantly with Multivariate ENSO Index (MEI) and Southern Oscillation Index (SOI) in parts of northern coastal areas close to the sea, while a common insignificant linkage was detected between CDD/CWD and large-scale circulation indices such as North Atlantic Oscillation (NAO), Northern Oscillation Index (NOI), Atlantic Multidecadal Oscillation (AMO) and Pacific Decadal Oscillation (PDO) over CAC. Results from this paper are anticipated to provide insights into the drought/flood disaster risk mitigation and prevention as well as water resources management in the coastal area of China. • Coastal area of China (CAC) witnessed an obvious north-south difference in consecutive dry days (CDD) and consecutive wet days (CWD). • CDD and CWD varied insignificantly with a - trend rate of − 4.5–2.7 and − 0.7–0.6 days per decade, respectively. • A predominantly significant positive linkage was found between CWD and precipitation over CAC. • CDD and CWD correlated significantly with ENSO in parts of northern coastal areas close to the sea. [ABSTRACT FROM AUTHOR]

• A typical weathered granite tunnel which occurred five water and mud inrush disasters was presented as a case study. • A seepage-erosion coupled model was used to evaluate the safety thickness for this project. • Twenty-five grouting cycles conducted in the field were described to analysis the safety thickness. • A detailed calculated method for safety thickness under various ground conditions was developed. The Junchang tunnel is a part of a major project in the Censhui highway in Guangxi province, China. The weathered granite part of the tunnel is approximately 180 m long with two lines and four lanes. Numerous water and mud inrush disasters frequently occurred in the weathered granite area, leading to serious economic loss and challenge to the constructors. Therefore, continuous grouting was carried out for the entire weathered part of the tunnel. This paper describes its curtain grouting for disasters prevention. Detailed discussion is presented on the safety thickness after grouting and the challenges encountered under different hydraulic-geological conditions. Specifically, a water and mud inrush model for the nonlinear flow and mass transfer behavior of weathered granite was used to evaluate the safety thickness in this project. Then, field studies with twenty-five grouting cycles and excavations were conducted to investigate the effective safety thickness. Negative correlation was observed between the safety thickness and the rock classification index [BQ]. Numerical simulation and field tests demonstrated that the thickness l should be larger than 3 m, and, in most cases, 5 m was sufficient when [BQ] < 72.5. When [BQ] ≥ 72.5, l should be between 1.5 m and 3 m. Based on the field data, an empirical formula was developed to determine the thickness under different values of [BQ]. The research findings serve as an important reference for future projects in similar stratum. [ABSTRACT FROM AUTHOR]

Background/Objectives: China is actively promoting the reform of its economic structure and industrial upgrade, and the integration of the cultural industry and the tourism industry is an important approach. It is necessary to explore the degree of coordination and coupling between the cultural industry and the tourism industry in ethnic minority areas and find ways to promote the coordinated development of the two industries. Methods/Statistical Analysis: This study selected Guangxi Zhuang Autonomous Region as the sample, collected data from 2010 to 2018, and analyzed it based on the coupling coordination theory. Findings: The results revealed that the comprehensive development evaluation index of the cultural industry and the tourism industry basically showed a year-on-year upward trend, and the development speed of the cultural industry is slightly higher than that of the tourism industry; the coupling degree of the regional cultural industry and tourism industry was at a high level; the coordination degree of the two industries increased gradually from 0.3971 in 2010 to 0.9425 in 2018. It indicated that the coupling development of the two industries continues to improve. However, the development speed of tourism industry slightly was slower than the development speed of the cultural industry. Improvements: This study attempts to develop an index to evaluate the tourism and cultural industries in an ethnic minority region and assess the coupling and coordination degree through an empirical analysis. This study emphasizes the need to better understand the integration of the cultural industry and the tourism industry as a process to complement each other, which can produce a positive synergy effect to benefit both the economy and the environment. This paper also provides development suggestions for the culture and tourism industry stakeholders in other areas of the world from the perspective of open innovation. [ABSTRACT FROM AUTHOR]

The study results of Zn, He-Ar and Sr-Nd of the Tongkeng deposit show that Zn source mainly comes from the Cretaceous Longxianggai granite magmatic fluid, classified into the type of post-magmatic hydrothermal filling-metasomatism. He-Ar isotope study shows that the mantle-sourced substances involved in the mineralization are related to that of the Devonian Liujiang Formation exhalative sedimentary sequences. • The Longxianggai granite belongs to the typical remelted S-type granite. • The mantle-sourced substances in ores are from the Devonian exhalative sediments. The Zn most likely derived from the Cretaceous Longxianggai granite. The Tongkeng tin-polymetallic ore deposit in Nandan County, Guangxi Zhuang Autonomous Region, southern China, is the representative deposit of the largest scale in the famous Dachang tin-polymetallic ore field. It consists of the upper tin-polymetallic ores and the lower newly found zinc-copper ores with the Sn metal reserve of 680,000 tons (average grade 1%), 4,500,000 tons of Zn (average grade 4%), and 80,000 tons of Cu (average grade 0.2%). The orebodies occur as layers and veins within the Middle to Late Devonian siliceous rocks and carbonate rocks. In this paper, the isotopic compositions of Zn, He-Ar and Sr-Nd of the Tongkeng deposit have been studied systematically. The results show that the isotopic composition of Zn is quite homogenous with δ66Zn = 0.22 ~ 0.34‰ in sphalerite samples of various colors from brown to black, collected from different orebodies (upper tin-polymetallic and lower zinc-copper ores) in the Tongkeng deposit. It indicates that Zn source mainly came from magmatic fluid, as the calculated δ66Zn (0.42 ~ 0.54‰) of ore-forming fluid is almost same as that of the Longxianggai granite (0.41 ~ 0.55‰), but quite different from that of the marine carbonate (average 0.91‰). He-Ar isotope study of pyrite shows that the exhalative substances might have been involved in the mineralization, with 3He/4He = 1.2 Ra ~ 2.5 Ra in the upper tin-polymetallic ores and 3He/4He = 0.8 Ra ~ 1.9 Ra in the lower zinc-copper ores in the Tongkeng deposit, which is different from that of the Longxianggai granite (3He/4He = 0.7 ~ 0.8 Ra), but close to that of the Devonian Liujiang Formation exhalative sedimentary sequences with 3He/4He = 1.5Ra. The Longxianggai granite has I Sr = 0.719 (in average), εNd(t) = -7.9 ~ -9.6 and Nd model age T 2DM = 1.54 ~ 1.68 Ga. Based on the geochemical characteristics of granite and Sr, Nd and O isotopes, the source rocks of the Longxianggai granite may be mainly derived from the continental crust, which is a typical remelted S-type granite. Based on the results of this study and the previous data in the literature, it is concluded that the mineralization in the Dachang ore field is closely related to the Cretaceous Longxianggai granite in time and space with the main metal substances of Zn most likely derived from the magmatic fluid, classified into the type of post-magmatic hydrothermal filling-metasomatism. The admixing of the early Devonian spouting sediments in the mineralization was evidenced in the study of source trace and has led to the longtime dispute over the ore genesis. [ABSTRACT FROM AUTHOR]

• An end-to-end model is proposed for rice yield prediction using deep learning fusion. • Deep spatial-temporal features significantly reduced prediction errors. • The model converges quickly to low errors and provides stable prediction performance. • The model achieves the optimal prediction performance when the number of layers is 6. Rice yield is essential for more than half of the world's population, and thus, accurate predictions of rice yield are of great importance for trade, development policies, humanitarian assistance, decision-makers, etc. However, traditional mechanistic models and statistical machine learning models need to identify features, making the research on and application of these models laborious and time-consuming. In this paper, a novel end-to-end prediction model that fuses two back-propagation neural networks (BPNNs) with an independently recurrent neural network (IndRNN), named BBI-model, is proposed to address these challenges. In stage one, BBI-model preprocesses the original area and meteorology data. In stage two, one BPNN and the IndRNN are used to learn deep spatial and temporal features in parallel. In stage three, another BPNN combines two kinds of deep features and learns the relationships between these deep features and rice yields to make predictions for summer and winter rice yields. The experimental results indicate that BBI-model achieved the lowest mean absolute error (MAE) and root mean square error (RMSE) for the summer rice prediction (0.0044 and 0.0057, respectively) and corresponding values of 0.0074 and 0.0192 for the winter rice prediction when the number of layers in the network was set to six. Moreover, the errors of the model using the combination of deep spatial-temporal features were significantly lower than when simply using deep temporal features. Furthermore, the model converged quickly with 100 iterations and then remained stable. These findings confirm that the model can make accurate predictions for summer and winter rice yields of 81 counties in the Guangxi Zhuang Autonomous Region, China. [ABSTRACT FROM AUTHOR]

• Six granite phases can be distinguished at the Jiepai deposit. • Four W and three Cu mineralization events are identified at Jiepai deposit. • The granites reveal a complex evolution process that involved two or more sources of magmas. The Jiepai W-Cu deposit, located in the northeastern Guangxi Zhuang Autonomous Region in South China, occurs along the contact zone between the Yuechengling granite batholith and the Cambrian dolomitic limestones and slates. The main body of the batholith is made of a Silurian monzogranite in the south and a Triassic monzogranite in the north. A number of Jurassic to Cretaceous fine-grained granite intrusions are present as stocks and dikes intersecting the batholith. The deposit includes five types of W-Cu ores, including (1) contact-zone scheelite skarn occurring at the lithological contact between monzogranite and dolomitic limestone, (2) strata-bound scheelite skarn hosted by dolomitic limestone, (3) disseminated or banded scheelite within gneissic granite, (4) titanite-bearing scheelite quartz veins cross-cutting the skarns and limestone, and (5) disseminated Cu sulfides within granodiorite, respectively. In this paper, we report new geochronological data obtained from zircon U-Pb, molybdenite Re-Os, and biotite and muscovite Ar-Ar analyses with the aim of constraining the timing of magmatic and mineralization events. Zircon SHRIMP U-Pb analyses of all the granitoids exposed in the deposit and its vicinity reveal six stages of magmatic emplacement dated at 448.4 ± 4.6 Ma, 434.6 ± 3.5 Ma, 429.4 ± 7.6 Ma, 219.2 ± 1.5 Ma, 156.0 ± 3.0 Ma, and 149.7 ± 2.2 Ma (weighted 206Pb/238U mean ages). Molybdenite Re-Os and muscovite and biotite Ar-Ar analyses reveal four W mineralization events that were associated with the magmatic emplacement at 448.4 ± 4.6 Ma, 429.4 ± 7.6 Ma, 219.2 ± 1.5 Ma, and 151.4 ± 1.9 Ma, and three Cu mineralization events at 434.3 ± 5.1 Ma, 152.2 ± 1.1 Ma, and 141.0 ± 2.5 Ma, respectively. The granites at the deposit and its vicinity document weak fractionation of light and heavy REEs, contain low concentrations of Ba, Nb, Sr, P, and Ti, but high concentration of Ta. Neodymium isotopic data of the W-mineralized Late Ordovician granites (ε Nd(t) = −4.87, T 2DM = 1.6 Ga) imply magma mixing of mafic mantle material with Paleoproterozoic and/or Mesoproterozoic continental crust. By contrast, the Silurian granites (ε Nd(t) = −10.15 to −13.49) were formed by anatexis of the Paleoproterozoic continental crust. High-precision Hf-O isotope data obtained in this study indicate partial melting of the lower crust as the main source of the younger granites, and further reveal a complex evolution process that involved two or more sources of magmas. [ABSTRACT FROM AUTHOR]

After the end-Permian mass extinction (EPME), the marine environment was considered extremely toxic, mainly due to anoxic and high-temperature conditions and ocean acidification; consequently, the ecosystem contained few organisms. This paper describes a new ostracod fauna from the microbialite-bearing Permian-Triassic (P-Tr) strata at Zuodeng, Guangxi region, China. One thousand and seventy ostracod specimens were extracted from forty-eight samples. Fifty-three species belonging to fourteen genera were identified. Ostracods, primarily from the family Bairdiidae, were extremely abundant in the microbialites, which suggests that ostracods were opportunists that could survive the EPME within this special microbial ecosystem with sufficient food and scarce competitors and predators rather than undergoing a rapid and early recovery after the EPME event. Ostracods having simultaneous Paleozoic and Meso-Cenozoic affinities coexisted in this fauna. The similarities and differences among the ostracod faunas in the microbialite sections of the P-Tr boundary around the Paleo-Tethys indicate that there was a long-distance dispersal of ostracods, but the faunas maintained endemism at the species level. Previous studies have regarded microbialites as whole units, and it is difficult to detect environmental changes within a microbialite interval based on paleoecological groups of (super)families. In this study, high-resolution sampling was applied to identify changes in the ostracod abundance, diversity, assemblages and proportion of five dominant species in the section, which exhibited an evolutionary trend from the " Bairdia " group to the " Liuzhinia antalyaensis - Bairdiacypris ottomanensis " group. Furthermore, the transition of the ostracod fauna could be divided into six stages according to changes in the dominant species groups, suggesting that the microbialite environment was not entirely monotonous but fluctuated during the postextinction interval. • Microbes support an ostracod-friendly environment after end-Permian mass extinction • Ostracod evolution relates to the growth and demise of Permian-Triassic microbialites • Composition of ostracod fauna changes even in the same structure of microbialites • Six paleoenvironment fluctuation stages recognized by dominant species of ostracods • High-definition study on ostracods helps to understand more about microbialites. [ABSTRACT FROM AUTHOR]