Search

Sintered ore is the most important incoming iron material for blast furnaces in China. The foundation characteristics of sintering are an important basis for the sintering process of iron ore powder and a key indicator for evaluating the quality of iron ore powder. The chemical composition of iron ore powder directly affects the foundation characteristics of sintering. Based on the chemical composition and sintering characteristics of iron ore powder, the article adopts the FOA-Catboost algorithm to establish a prediction model for the foundation characteristics of single iron ore powder and mixed iron ore powder. Among the foundation characteristics prediction indicators of a single type of iron ore powder, the accuracy of assimilation temperature prediction is 95.65 %, the accuracy of fluidity index prediction is 95.23 %, and the accuracy of bonding phase strength prediction is 97.46. Among the foundation characteristics prediction indicators of mixed iron ore powder, the accuracy of assimilation prediction is 95.82 %, the accuracy of fluidity index prediction is 91.66 %, and the accuracy of bonding phase strength prediction is 93.7 %. On the basis of predicting the foundation characteristics of a single type of iron ore powder, the model further predicts the foundation characteristics of mixed iron ore powder, which can reduce the workload of laboratory experiments on the foundation characteristics of iron ore powder and reduce the amount of experiments in the process of finding the optimal proportion of mixed ore. Based on the foundation characteristics model of mixed ore, determine the optimal ratio of sintered ore powder to improve the quality of sintered ore. The establishment of the model has a significant contribution to improving experimental and production efficiency, reducing costs, improving sinter quality, and reducing environmental impact. [ABSTRACT FROM AUTHOR]

Estimates of grassland aboveground biomass (AGB) upscaled from the plot level to broad scales are lacking extrapolation robustness across grassland biomes. This is because the coupling relationships between diverse driving variables and model forms are poorly understood and/or are not robustly defined. Here, using 17,421 in situ ground-truth AGB samples and 31 driving variables generated from Sentinel-1/2 satellite images and climatic-topographical-soil data, we explored the coupling relationships among these multifaceted driving variables and 6 machine learning (ML) algorithms in AGB upscaling estimates across 18 grassland types in China. Monte Carlo simulations indicated that these 31 multifaceted driving variables did not enhance the performance of the ML algorithms in AGB modeling and that prioritizing climatic factors at a 10 km resolution and the satellite enhanced vegetation index (EVI) at a 10 m resolution have scale effects; the former dominates the variation in grassland AGB among 18 grassland types, and the latter reflects local heterogeneity. ML algorithms prevalently suffer from saturation convergence, and the underrepresentation of training samples leads to instability in ML establishment when constrained to a specific grassland type. Among the 6 ML algorithms, the random forest (RF) algorithm outperformed the other methods in terms of the mean absolute error (MAE) during iterative training; however, the best performance strongly relies on saturated training, with an R2 of 0.68 over all grasslands in China. Finally, based on the optimal estimate of grassland AGB using RF (0.25 Pg C) and both belowground biomass (1.52 Pg C) inferred from the ratio of roots to shoots (R/S) of the 18 grassland types and the approximate intake of grazing animals (0.02 Pg C), the plant-based carbon stock over Chinese grasslands is estimated to be 1.79 Pg C. This study emphasizes that to untangle the limitations of using ML approaches, the robustness of model training and the complementary effect between climatic factors and satellite metrics should be considered when upscaling estimates of grassland AGB. • An ML scheme was developed to scale up the AGB estimates across 18 grassland types. • The coupling relationships between diverse driving variables and AGB were clarified. • Coarse precipitation and EVI have a complementary role in modeling AGB variation. • The saturated training of ML guarantees converging robustness among grassland types. • The plant-based carbon stock in Chinese grasslands was estimated to be 1.79 Pg C. [ABSTRACT FROM AUTHOR]

As a major source of carbon emissions, the civil aviation sector needs a feasible path for low-carbon transition. Owing to the dynamics of travel demand in China, the spatial patterns of aviation emissions are difficult to foresee or simulate in scenario analysis. To address this issue, we predicted the spatial patterns of aviation carbon emissions in China at the city level using projected gridded population data and power law model. The results show that China's civil aviation sector will have a cumulative emission abatement potential of 7027 million tons from 2020 to 2060 if all abatement measures can be implemented. The contribution of individual cities was quantified based on expected changes in population, airport planning, and economic development. Megacities and metropolitan cities will contribute to 58.1 % and 26.2 % of the total emission abatement, respectively. The eastern, central, and western regions of China will contribute to 64.2 %, 15.8 %, and 20.0 % of the total abatement, respectively. The abatement potentials before and after 2040 are expected to account for 20.0 % and 80.0 % of the whole from 2020 to 2060. Therefore, some regions and cities can be regarded as key or pilot areas to implement abatement measures. Finally, policy implications of the results are presented. [Display omitted] • Predict the spatial pattern of carbon emissions of China's civil aviation sector at the city level. • Use gridded population and economic development data, and power-law model. • Sustainable development scenario can abate 7027 Mt of emissions during 2020–2060. • Mega cities contribute to majority of the emissions abatement in future. • Eastern, central, and western cities contribute to 64 %, 16 %, and 20 % of the abatement. [ABSTRACT FROM AUTHOR]

We present a systematic study of the petrological, mineralogical, sedimentological, and elemental geochemical characteristics of Cambrian Stage 3 red beds in the Hannan-Micangshan area of South China. The results show that red beds in the study area were mainly deposited in shallow marine environments, including the littoral and deeper neritic zones. Hematite and ferric hydroxides are the major pigmentary minerals in the red beds, and their origin is related to the contribution of iron-bearing minerals in the terrestrial fine-grained fraction during diagenetic transformation, based on evidence from many co-occurring iron-bearing terrestrial and clay minerals (e.g., ilmenite, chamosite, and glauconite), distinct diagenetically-altered characteristics, and close relationships between total Fe and Al, Mg, and Ti. The data also provide compelling evidence for presence of seawater-derived ferric hydroxides in shallow marine environments through in-situ technique analysis. Distinct lithological and sedimentological features in the study area allow the conclusion that diagenetic and hydrogenic ferric oxides/hydroxides jointly promoted the formation of the red beds. The present study found that the combination of active tectono-magmatic events, enhanced terrestrial fluxes, and improved dissolved oxygen conditions may have provided abundant iron sources and iron availability during the sedimentary and diagenetic processes, and thus facilitating the occurrence of red beds globally in Cambrian Stage 3. • Red beds were deposited on a global scale during Cambrian Age 3. • Shallow marine red beds were mixed hydrogenetic-diagenetic. • A novel in-situ technique was used to distinguish the origin of pigmentary minerals. • Sedimentary processes controlled the distribution of shallow marine red beds. • Global tectonic and climatic changes facilitated iron availability in Cambrian Age 3. [ABSTRACT FROM AUTHOR]

• Metal bioavailability estimated by simple bioavailability extraction test (SBET). • Probabilistic integrated ecological risk assessment method (PIERA) was developed. • PIERA integrated SBET and triangular fuzzy numbers into Hakanson's eco-risk index. • Cd and areas around S2 and S5 was identified to be priority pollutant and areas. • Cd originated from both non-point agricultural and industrial pollution sources. Heavy metals (Cr, Cu, Zn, Pb, Cd) concentrations and fractions in surface sediments from Honghu Lake were detected by an atomic absorption spectrophotometer and Simple Bioavailability Extraction Test (SBET) from 11 typical sites to explore their spatial distribution, bioavailability and sources. Results showed the mean I geo s and ecological risk degrees decreased in the order of Cd>Cu>Cr>Pb>Zn and Cd>Cu>Pb>Cr>Zn. The metals' bioavailability estimated by SBET decreased in the general order of Cu>Pb>Cd>Zn>Cr. Under integrated consideration of metal enrichment, ecological risk and bioavailability, it obviously made the decision-makers confused to identify final priority pollutants and priority areas. Thus, a probabilistic integrated ecological risk assessment method (PIERA) was formulated based on the potential ecological risk index (PER), SBET and triangular fuzzy numbers for synthetically assessing metal enrichment, ecotoxicity and bioavailability. With the help of PIERA, Cd was finally regarded as the risk priority metal due to the integrated potential eco-risk of Cd made the average contribution of 86.4% to the integrated RI s. Moreover, the areas around S5 and S2 were regarded as the risk priority areas. The case application of PIERA revealed that this improved method is of a better resolving ability which scientifically supplies the integrated information of enrichment, bioavailability and systematic uncertainty for decision-makers compared with the other prevalent indexes (SQGs, I geo , PER). The consequence of the Pearson correlation analysis, distribution analysis and field investigation indicated that Cd mainly originated from both non-point agricultural and industrial pollution sources. [ABSTRACT FROM AUTHOR]

Two novel strains GSK1Z-4-2T and MQZ15Z-1 were isolated from branches of mangrove plants collected from Guangxi Zhuang Autonomous Region, China. Both strains were Gram-negative, aerobic, non-flagellated and non-spore-forming bacteria. The comparison of 16S rRNA gene sequences initially indicated that the two strains were assigned to the genus Ancylobacter with sharing the highest similarity to Ancylobacter pratisalsi DSM 102029T (97.3%). The 16S rRNA gene sequence similarity, average nucleotide identity (ANI) and in silico DNA-DNA hybridization (is DDH) values between strains GSK1Z-4-2T and MQZ15Z-1 were 99.9%, 97.4% and 77.4%, respectively, which revealed that the two strains belonged to the same species. Phylogenetic analyses based on 16S rRNA gene sequences and the core proteome showed that the two strains formed a well-supported cluster with A. pratisalsi DSM 102029T. Moreover, the ANI and is DDH values between strain GSK1Z-4-2T and A. pratisalsi DSM 102029T were 83.0% and 25.8%, respectively, demonstrating that strain GSK1Z-4-2T was a previously undescribed species. Meanwhile, strains GSK1Z-4-2T and MQZ15Z-1 exhibited most of chemotaxonomic and phenotypic features consistent with the description of the genus Ancylobacter. Based on the polyphasic data, strains GSK1Z-4-2T and MQZ15Z-1 should represent a novel species of the genus Ancylobacter , for which the name Ancylobacter mangrovi sp. nov. is proposed. The type strain is GSK1Z-4-2T (=MCCC 1K07181T = JCM 34924T). [ABSTRACT FROM AUTHOR]

Context Aconitum species are well-known for their medicinal value and high lethal toxicity in many Asian countries, notably China, India and Japan. The tubers are only used after processing in Traditional Chinese Medicine (TCM). They can be used safely and effectively with the methods of decoction, rational compatibility, and correct processing based on traditional experiences and new technologies. However, high toxicological risks still remain due to improper preparation and usage in China and other countries. Therefore, there is a need to clarify the methods of processing and compatibility to ensure their effectiveness and minimize the potential risks. Object The aim of this paper is to provide a review of traditional and current methods used to potentially reduce toxicity of Aconitum roots in TCM. Materials and methods The use of Aconitum has been investigated and the methods of processing and compatibility throughout history, including recent research, have been reviewed. Results and conclusions Using of the methods of rational preparation, reasonable compatibility, and proper processing based on traditional experiences and new technologies, can enable Aconitum to be used safely and effectively. [ABSTRACT FROM AUTHOR]

Studying the lacustrine microbialites in the Qaidam Basin may provide clues to the occurrence and mineralization processes of microbial communities in extremely harsh terrestrial environments. In the Eocene lacustrine systems of the Qaidam Basin, thick thrombolites (~0.4 to 1 m thick) generally formed in near-shore settings with rare to plentiful terrigenous admixtures and are characterized by four different clotted structures (i.e., maze-like, cortoid-like, tightly bound, and aggregated). In contrast, the small-scale stromatolitic, thrombolitic, and composite clotted-laminated microbialites (cm level) exhibit domical, columnar, and stratiform shapes, likely indicating that they developed in very shallow settings (e.g., a lagoon). The early lithification of the outer crusts and the internally laminated and clotted textures facilitated the preservation of the microbialites. The laminated and clotted textures of the Eocene microbialites analyzed in this study were composed of crypto- to micro-crystalline (mimetic) dolomite, which likely formed during the early mineralization process. This was likely caused by the strong evaporative lacustrine conditions on the Qinghai-Tibetan Plateau during the Eocene-Oligocene climate transition. The microbial mineralization process in dolomite-supersaturated pore fluids may also have contributed to early dolomitization. In contrast, the medium to coarsely crystalline components of the microbialites are composed of calcite minerals, implying that these components experienced cementation/recrystallization during diagenesis. In addition, large quantities of authigenic sulfate (celestite-barite) and sulfide (framboidal pyrite) minerals are exclusively distributed within the mimetically-dolomitized, laminated and clotted microbial structures. It is inferred that the saline lake conditions and the mineral dissolution (both carbonate and terrigenous particles) contributed to the SrSO 4 - and BaSO 4 -supersaturated fluid conditions and enabled the crystallization of celestite-barite. The development of Eocene lacustrine microbialites on the northeastern Qinghai-Tibetan Plateau provides a case for comparison with widely-distributed records of lake microbial carbonates, and the microstructural characteristics and analytical tools used in this study may offer a new perspective to explore the complex mineralization processes of microbialites. • The Eocene lacustrine microbialites on the Qinghai-Tibetan Plateau were studied. • We applied a novel, in-situ laser-ablation imaging technique to the microbialite. • Microbial laminated and clotted components experienced fabric-retentive dolomitization. • Plentiful authigenic sulfate and sulfide minerals are preserved in microbial structures. [ABSTRACT FROM AUTHOR]

Crop monitoring during the growing season is important for regional management decisions and biomass prediction. The objectives of this study were to develop, improve and validate a scale independent biomass model. Field studies were conducted in Huimin County, Shandong Province of China, during the 2006–2007 growing season of winter wheat ( Triticum aestivum L. ). The field design had a multiscale set-up with four levels which differed in their management, such as nitrogen fertilizer inputs and cultivars, to create different biomass conditions: small experimental fields (L1), large experimental fields (L2), small farm fields (L3), and large farm fields (L4). L4, planted with different winter wheat varieties, was managed according to farmers’ practice while L1 through L3 represented controlled field experiments. Multitemporal spectral measurements were taken in the fields, and biomass was sampled for each spectral campaign. In addition, multitemporal Hyperion data were obtained in 2006 and 2007. L1 field data were used to develop biomass models based on the relation between the winter wheat spectra and biomass: several published vegetation indices, including NRI, REP, OSAVI, TCI, and NDVI, were investigated. A new hyperspectral vegetation index, which uses a four-band combination in the NIR and SWIR domains, named GnyLi, was developed. Following the multiscale concept, the data of higher levels (L2 through L4) were used stepwise to validate and improve the models of the lower levels, and to transfer the improved models to the next level. Lastly, the models were transferred and validated at the regional scale using Hyperion images of 2006 and 2007. The results showed that the GnyLi and NRI models, which were based on the NIR and SWIR domains, performed best with R 2 > 0.74. All the other indices explained less than 60% model variability. Using the Hyperion data for regionalization, GnyLi and NRI explained 81–89% of the biomass variability. These results highlighted that GnyLi and NRI can be used together with hyperspectral images for both plot and regional level biomass estimation. Nevertheless, additional studies and analyses are needed to test its replicability in other environmental conditions. [ABSTRACT FROM AUTHOR]

As is known, the financial market prediction and high investing value is receiving more increasing attentions nowadays. But affected by many complex factors, it is difficult to perform the financial market forecast accurately. Among the solving methods, the time-series prediction has caused the focus for its great predictive effect in many fields. However, most of the existing works focus on single-time-series analysis and cannot obtain good learning results because it trains tasks independently and ignores the cross-correlation among multiple time series. Motivated by the multitask learning, a novel online multitask learning based on the least squares support vector regression (OMTL-LS-SVR) algorithm is proposed for multi-step-ahead financial time-series prediction. OMTL-LS-SVR regards multiple related time series as different learning tasks, which are trained in parallel to obtain the prediction model and shorten the training time. Under this scheme, the knowledge from one certain task can benefit others, allowing it to exploit the relatedness among multiple subtasks. The OMTL-LS-SVR is applied to perform the time-series tendency prediction in four branches of China's financial market, and the experimental results demonstrate the effectiveness of the proposed multitask learning algorithm. • An online multitask learning model is proposed for the financial market forecasting. • The cross-correlations among financial time series is well considered in OMTL-LS-SVR. • OMTL-LS-SVR adopts a fixed memory scheme to capture the latest dynamic features. [ABSTRACT FROM AUTHOR]

• China's aggregate inflow and stock markedly increased from 1978 to 2018. • The aggregate inflow reached a plateau in 2014. • The major consuming sectors shifted from buildings to infrastructure. • As a supply source, the trend has shifted from natural aggregates to manufactured ones. • Inflows and stocks have relatively decoupled from economic growth since reform and opening up. Aggregates are the most extracted material resources by weight worldwide. As an important resource for buildings and infrastructure, aggregates, however, are now facing shortages and are associated with negative environmental and social impacts. More attention is now paid to the sand and gravel issues, however, recent investigations are often found ambiguous in definition or adopting over-simplified accounting methodology. To bridge the knowledge gap, first, we conducted a detailed literature investigation to clarify the associated terms. Then we established a systematic material flow and stock accounting framework to map the social metabolism of aggregate resources for the largest aggregates consumer and producer—China. Our results show during 1978–2018, the inflows of China's aggregates increased by 13 times (1.3 to 17.3 billion tons) and the stocks increased by 15 times (18.3 to 285.5 billion tons). We observed both aggregate inflows and stocks have shown a relative decoupling from economic growth. Around 2014, inflows entered a platform area and the dominated consuming sector shifted from buildings to infrastructure. Due to supply shortages and policy interventions, the source of primary supply sees a sustainable transition: manufactured aggregates (instead of natural aggregates) gradually dominated, accounting for 78% of the total primary supply in 2018. Additionally, regarding accumulated stocks of aggregates, it is expected to see rapid growth of aggregate waste in the near future. It is essential to foster a well-functioned circular system to achieve the sustainable development of the aggregate industry. [ABSTRACT FROM AUTHOR]

The development of carbonate factories has potential importance in studies of paleoenvironment, sedimentology, and reservoir geology, but the mechanisms controlling the growth and demise of the large amount of carbonate sedimentation have not been broadly investigated, especially in terms of deep-time sedimentary records. Here, we provide a high-resolution study of the development and collapse of a series of tropical shallow-water carbonate factories distributed in the Hannan-Micangshan area of the South China Craton during the early Cambrian (Age 3). Unlike modern tropical shallow-water factories, the major carbonate producers in the early Cambrian factories contained ooids, benthic microbial communities (predominantly calcified microbes), and symbiotic microbial-skeletal organisms (i.e., calcimicrobial–archaeocyath bioherms). The ooid factories were mostly distributed in the tidal sand complexes around the Hannan-Micangshan massif; and some of the mixed quartz-ooid deposits may have been remodeled by terrigenous sands sourced from the adjacent fluviodeltaic delivery. The microbial carbonate factory was primarily characterized by thrombolites in terms of the lithological composition, with a small contribution of stromatolites and oncolites (grain sizes mostly of 2–4 cm). The thrombolites formed not only mound architectures individually (length of ~1–5 m, and height of ~0.5–2.5 m), but also small- to large-scale bioherms associated with reef-building skeletal organisms (i.e., archaeocyaths). Nutrient conditions may have played an essential role in regulating the distributions of the microbial and microbial-skeletal factories (mesotrophic conditions), but they did not have a significant effect on the ooid factories. These tropical shallow-water carbonate factories were located in oxygenated aqueous environments with some small transient low-oxygen intervals that corresponded to barrier microbial and microbial-skeletal factories in the study area. Hydrodynamic condition and other controls (e.g., wind) may have played roles in shaping the factory morphology and distribution features in the study area. The chemical index of alteration (CIA; values of 60–65) and petrological features (occurrence of large-scale ooid sand complexes) support a warm and dry climate during the development of these tropical shallow-water factories. Finally, the transition from carbonate-dominated to siliciclastic-dominated depositional systems driven by wetter climate conditions (CIA, close to 70) may have been responsible for the cessation of the shallow-water carbonate factories in the Hannan-Micangshan area, which resulted in a rapid drowning, and subsequently, continuous input of a high volume of siliciclastics in late Age 3 to early Age 4 (Yanwangbian Formation). This study provides clues to understanding the growth and demise of deep-time tropical carbonate factories and serves as a valuable reference for studies of other regions and time periods. • We present a high-resolution study of the tropical shallow-water carbonate factories. • These factories contained ooids, calcified microbes, and skeletal organisms. • Nutrient conditions may have played a key role in regulating factory distributions. • Hydrodynamic condition and wind shaped the factory morphology and distribution. • The shift of the depositional system was likely responsible for factory collapse. [ABSTRACT FROM AUTHOR]

Two novel strains KQZ13P-1T and MAQZ13P-2 were isolated from bark of Sonneratia apetala collected from Maowei sea Mangrove Nature Reserve in Guangxi Zhuang Autonomous Region, China. Two strains were Gram-positive, aerobic, non-spore-forming, no diffusion pigment actinobacterial strains and investigated by a polyphasic approach to determine their taxonomic position. The average nucleotide identity (ANI) value and the digital DNA-DNA hybridization (dDDH) value between the two strains were 99.9% and 99.7%, respectively, suggesting that they belonged to the same species. The ANI and dDDH values between strain KQZ13P-1T and five Phycicoccus species were 74.4–95.3% and 20.1–61.5%, respectively. Phylogenetic analyses based on 16S rRNA gene sequences showed that the two strains were member of the genus Phycicoccus and were closely related to P. jejuensis NRRL B-24460T (99.2% sequence similarity), followed by P. ginsengisoli DCY87T (97.5–97.6%). Moreover, based on 88 core genes, the phylogenomic tree indicated that the two strains clustered with P. jejuensis NRRL B-24460T. The cell-wall peptidoglycan of both strains contained meso -diaminopimelic acid. The major fatty acids in two strains were C 17:1 ω 8 c , iso-C 15:0 and iso-C 16:0. The major polar lipids included diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE) and phosphatidylinositol (PI). Based on phylogenetic, phenotypic and chemotaxonomic analysis, strains KQZ13P-1T and MAQZ13P-2 represent a novel species of the genus Phycicoccus , for which the name Phycicoccus mangrovi sp. nov. is proposed. The type strain is KQZ13P-1T (=CGMCC 1.18973T = JCM 34556T). [ABSTRACT FROM AUTHOR]

Widespread development of microbialites harbors a series of clues about microbial activity, environmental condition, and aquatic chemistry. The Ediacaran-Cambrian transition draws extensive attention on the co-evolution of complex life and Earth's environment but the associated microorganism development has been largely ignored. In this study, we present a high-resolution database with respect to the spatial and temporal distributions of microbialites in China through the terminal Ediacaran to the early Cambrian Period and describe morphological and petrological characteristics of stromatolites and thrombolites in detail to shed light on the evolutionary process of microbial carbonates. Microbialite development experienced two thriving intervals during the Ediacaran-Cambrian transition: latest Ediacaran to early Fortunian, and Cambrian Age 3 to middle Age 4. The columnar and domical stromatolites show no marked morphological changes in the Ediacaran-Cambrian transition, but stratiform stromatolites exhibit a notable decline in Cambrian time, likely caused by increasing bioturbation in the Cambrian shelf environments. Meanwhile, thrombolites evolved to form large and complicated structures in the early Cambrian featured by meter-level mound morphology and columnar-branching microbial forms (fan-like/dendritic structures), likely indicating an improved environmental adaptation (e.g., photosynthesis efficiency and hydrodynamic conditions). Another remarkable change in microbialites is the emergence of large numbers of calcified microbial microfossils preserved within the laminated/clotted mesostructures in Cambrian facies, compared with the Ediacaran forms that lack such unique structural features. For the main control over the Cambrian microbial calcification event, this study stresses again the essential role of seawater chemistry (Mg/Ca molar ratios and Ca2+ concentrations) in the formation and preservation of calcified microorganisms based on previous insights and elaborate characteristics of their occurrence and microstructures in China. The transition of the Neoproterozoic "aragonite-dolomite sea" to the Cambrian "calcite sea" (likely widely distributed in Age 3) may have promoted to the generation of an original calcite mineralogy in microbial fossils, which has a stronger ability to resist diagenetic dissolution and substitution (e.g., phosphatization and silicification) than that of the aragonite precursor. • We present a high-resolution database with respect to the development of microbialites in China through the E-C transition. • Detailed morphological and petrological characteristics of stromatolites and thrombolites are described. • Microbialite development experienced two thriving intervals in China during the E-C transition. • Thrombolites evolved to form large and complicated structures, likely indicating an improved environmental adaptation. • The primary calcite mineralogical composition is one potential reason for the preservation of the calcified microfossils. [ABSTRACT FROM AUTHOR]

• Identify optimized three-band spectral indices for estimating the canopy N uptake of corn and wheat. • The optimized NPDI estimated canopy N uptake of both corn and wheat alone and in combination. • Our algorithm may allow the design of improved N diagnosis systems. Nitrogen (N) fertilization management plays an important role in optimizing crop growth and yield. Concerns over environmental risk require a quick, accurate, non-destructive determination of the N status of crops. Hyperspectral remote sensing allows a timely monitoring of the in-season crop N status. Although many spectral indices for assessing the N status of crops have been proposed, it is still necessary to further optimize the central bands, since they often vary with plant cultivars and species. To improve this, we identified optimized three-band spectral indices for estimating the canopy N uptake of corn and wheat. Experiments were conducted from 2009 to 2011 by evaluating and testing optimized three-band spectral indices for estimating the N status of wheat cultivars grown in Germany and China and corn cultivars grown in China. The indices generally enabled more robust predictions compared to published indices. The central bands suitable for assessing the canopy N uptake were 768, 740, and 548 nm for corn; 876, 736 and 550 nm for wheat; and 846, 732 and 536 nm for corn and wheat combined. Both wheat and corn assessed individually as well as in combination where sharing similar wavebands reflected by the species-specific and interspecies-specific optimized three-band spectral indices, e.g. the wavelengths 740, 736 and 732 nm were identified as optimum for corn, wheat and their combination, respectively. The validation results suggest that predictions using the optimized three-band N planar domain index (NPDI) delivered the highest coefficient of determination (R2 = 0.86) and the lowest root mean square error (RMSE, 20.1 kg N ha–1) and relative error (RE, 18.7 %). The optimized NPDI consistently estimated canopy N uptake of both corn and wheat alone and in combination. Therefore, the optimized three-band algorithm is an attractive tool for optimizing and identifying central bands. Our algorithm may allow the design of improved N diagnosis systems and enhance the application of ground- and satellite-based sensing. [ABSTRACT FROM AUTHOR]

In facing the challenge of PM2.5 pollution across China, an overall macro-evaluation of the spatiotemporal pollution distribution and health risk of PM2.5-bound heavy metals at a national level is urgently needed. This study involved a bibliometric analysis of 8 PM2.5-bound heavy metals (Cd, Cr, Hg, As, Pb, Cu, Zn, Ni) in the 27 major cities across China from 2013 to 2019 that was combined with valid data from the published scientific literature. Based on time weight vector, the spatiotemporal metal distributions and their integrated enrichment factors were analyzed, and then a fuzzy health risk assessment model was established to synthetically screen regional priority control regions/pollutants, and explore the pollution trend. The integrated concentrations of As (19.44 ng/m3) and Cd (4.12 ng/m3) in most cities exceeded the limits of the Chinese Ambient Air Quality Standards, while Hg (0.81 ng/m3) and Pb (137.10 ng/m3) did not. Spatially, PM2.5-bound heavy metal pollution generally increased from southern to northern China, with North and Northwest of China being relatively hot regions. For integrated health risks, children (3.31) faced higher non-carcinogenic risks than adults (1.69), with As, Cd, and Cr as the main contributors. The total carcinogenic risk varied from 4.86 × 10−6 to 1.3 × 10−3. The total carcinogenic risk of 77.78% of major cities has reached Grade V (moderate-high risk) or above, and the risk contributions of Cr and As accounted for the largest proportion. The temporal variations showed that the pollution had a recent declining trend in most cities. Finally, 10 major cities and their corresponding metals were determined as the priority control cities/metals. The targeted risk management policies were developed for the identified hierarchical hot cities and their priority pollutants to control were based on the regional pollution trend and source characteristics. Image 1 • Spatiotemporal heavy metals in PM2.5 was investigated in the Chinese major cities. • Fuzzy exposure assessment model was established to identify hot pollutants/areas. • Integrated heavy metals in PM2.5 increased gradually from south to north China. • Priority control metals were As, Cr, Cd, especially in north and northwest China. • Targeted policies for priority control regions were formulated on source analysis. [ABSTRACT FROM AUTHOR]

Environmental Kuznets Curve (EKC) has become the predominant approach between environmentalists and sociologists to modeling environment-economy nexus during the past quarter century, also with regard to China, the largest industrial pollutant emitter in the world, where unprecedented change offers a unique approach to the aggregate emissions. In the case of China the question is whether a tipping point can be reached without de-industrialization and at a lower income phase than in developed economies. It is also the worldwide intrinsic concern of environment-economy nexus in the prospective industrialization process of developing countries. However, China relative researches involve some existing challenges, such as cross-regional time series, various socioeconomic drivers, and turning thresholds. Taking the new normal China economy formulation into consideration, a rethink and reexamination of the environment-economy relationship was performed, using the longest possible environmental and economic data from 30 provincial economies for the period of 1985–2017. Different from the existing mostly time-series based China EKC literature, not only the LLC, IPS, Fisher unit root tests, Pedroni and Kao panel cointegration tests and the panel OLS are used, but, the problem of cross-sectional dependence is handled in panel unit root tests across various cross-economies, and the error-correction based cointegration test is employed, allowing for various forms of heterogeneity, robust against the cross-sectional dependence, and the DOLS estimators are applied to resolve the standard OLS for serial correlation and for endogeneity of regressors, especially in only small possible China samples. In particular, the finding contrasts with the overly optimistic research of certain scholars, who state that China could be on a clearly different path from the routes of some developed economies in the world, realizing the environmental turnaround at low levels of economy and industrialization. China economy is not just having a certain environmental "dividend effect", but mainly faces a more significant environmental "pressure effect". Environmental input and its efficiency is still insufficient to perform the intended pollution reduction effects. Fundamentally, the environmental investment as a proportion of GDP should reach the past levels of some developed economies in the similar pollution-economy phase. [ABSTRACT FROM AUTHOR]

• We report a newly-discovered deposit of giant ooids in middle Ediacaran (EP2) from China. • Petrographic and geochemical evidence support weak diagenetic alterations of giant ooids during burial. • Pure giant ooids can be a reliable achieve of seawater REE compositions in the middle Ediacaran. • Giant-ooid records provide a snapshot into palaeoceanographic conditions during this crucial period of dynamic changes. • The characteristics of Ce anomalies and REY compositions indicate the suboxidized surface ocean in South China. The Ediacaran was a period of intense environmental change in Earth history. Transient pulses of oxygenation and shifts in ocean chemistry have been interpreted from a range of geochemical proxies, including rare earth elements and yttrium (REY), but it is still a challenge to reconstruct paleoceanographic conditions due to the scarcity of reliable recorder. In this study, we explore the possibility that a newly-discovered deposit of giant ooids in the Nanshanping outcrop in South China contains a relatively intact record of the REE composition of Ediacaran seawater, providing an important window into the redox state of the surface ocean at this time. These ooids are relatively large in size (~1–6 mm), and exhibit densely banded laminae. A regional chemostratigraphic correlation shows that the giant-ooid-bearing succession in South China is in the upper part of the second Ediacaran positive carbon isotopic shift (EP2), and thus its occurrence was not associated with the Shuram Excursion. Additionally, the occurrences of giant-ooid-bearing oolites in different blocks were not synchronous during the middle Ediacaran. In-situ laser ablation analysis of giant-ooid cortices reveals that the shale-normalized REY patterns are similar to those of modern seawater, including depleted light REEs, superchondritic Y/Ho ratios, and positive La anomalies. Yet, no Ce anomalies (1.0 ± 0.15) in numerous ooid cortices seems to indicate a suboxidized condition of surface ocean in South China at that time. The petrographic and geochemical evidence support the weak diagenetic alteration of the pure giant ooids during burial. They formed in open-ocean settings with energetic hydrodynamic environments and were affected by early dolomitization that might preserve mostly original petrographic fabrics and REY signatures from further diagenetic overprinting. The characteristics of Ce anomalies and REY compositions acquired from the giant ooids indicate that the surface ocean was suboxidized in South China during the late stage of EP2, implying the very low atmospheric O 2 level at that time. Our results suggest that giant ooids may be a reliable analytical target that provide a snapshot into palaeoceanographic conditions during this crucial period of dynamic changes in early Earth history. [ABSTRACT FROM AUTHOR]

Determination of the pulmonary bioaccessible fraction and its induced health risk with respect to the toxic metals present in tobacco smoke is a significant issue, in terms of scientific and proactive management of clean tobacco production and smoker health. China, the world's largest producer and consumer of tobacco, has about 350 million smokers. The four typical toxic metals in the 20 top selling cigarette brands in China were investigated. The mean levels of As, Cd, Ni, and Pb in tobacco were 0.3891 μg/g, 3.8431 μg/g, 2.4356 μg/g, and 2.7718 μg/g, respectively. Pulmonary bioaccessibility was analyzed by extraction using simulated lung fluid (SLF), where the average rates of As, Cd, Ni, and Pb transferring from tobacco to SLF by mainstream smoke (RSLF) were 7.85%, 2.85%, 0.86%, and 3.45%, respectively. Considering the inhalation pathway of mainstream smoke, an improved health risk assessment (HRA) was conducted using local exposure parameters and fuzzification of sensitive variables. With consideration of the exposure differences of smokers, Cd and As were identified as the priority control metals, and B05, B11, B12, and B19 among the 20 brands (named B01–B20) were found to be the priority control brands. Furthermore, it is worth noting that the membership degrees of a small portion of brands which approached 50% could warn decision-makers of potentially misleading uncertainties. The daily consumption limit (DCL) for each studied brand was calculated, under the risk standard value of Level II (1.00E-05), generally ranging from 1 to 4 cigarette(s) per day. Spatially, DCLs in Southern, Southwestern, and Eastern China were relatively lower than those in other regions. At present, it is of significance to establish a national life-cycle supervisory system for Cd and As. Findings about the health risks posed by toxic metals through the tobacco–smoke–lung exposure pathway can provide scientific risk management reference for smokers, related managers, and producers. Image 1 • Toxic metals in the selected 20 Chinese best-selling cigarettes were investigated. • Pulmonary bioaccessibility of toxic metals was analyzed using simulated lung fluid. • Transfer rates from mainstream smoke to simulated lung fluids (RSLF) were detected. • Health risk posed by tobacco metals was assessed with fuzzy theory and RSLF. • Cd and As need priority control and cigarette consumption limits of brands are 1–4/d. [ABSTRACT FROM AUTHOR]

The refractive index of ambient aerosols is one of the most important parameters indicating the scattering and absorption properties of aerosols. We proposed a new method for retrieving the refractive index (RI) of ambient particles. The main advantage of our method is that it assimilates the single particle mixing states measured by a single-particle soot photometer, when compared to the traditional optical method of retrieving the ambient aerosol RI. This method was validated by good consistency between the determined RI with this method and retrieved RI with the method of Zhao et al. (2019c) using datasets from field measurements conducted in East China in June of 2018. The results show that the real part of the refractive index of the black carbon (BC)-free particles ranged between 1.37 and 1.51 and this value changed little across different tested wavelengths. The mean complex refractive index for the refractory BC was 1.67 ± 0.67 i at 525 nm. The mean imaginary parts of the other non-BC components were 0.019 and 0.023 at 450 nm and 370 nm respectively. Brown carbon contributed to 5%, 13% and 29% of the ambient aerosol light absorption at 525 nm, 450 nm and 370 nm respectively in East China. This study provides the ability to determine the ambient aerosol complex refractive index and these data can be used in models to reduce the uncertainties in estimating aerosol radiative forcing. • A new method for determining the refractive index with assimilating the single-particle mixing states is proposed. •The refractive index of black carbon-free aerosols at the wavelength of 525 nm varied over a wide range between 1.37 and 1.51. •The mean complex refractive index of black carbon was 1.67 ± 0.67i at 525 nm. [ABSTRACT FROM AUTHOR]

Recently frequent hazy weather in China caused by PM2.5 is mainly attributed to irrational energy consumption structure, so the policies cutting coal output and promoting electric power substitution were initiated. Facing some resistance in the policy implementation, what the proper target of cutting coal output is, or whether there is a need to cut electricity prices for electric power substitution, are still unknown or debatable. To exploring this knowledge gap, this paper set the eight action plan policy scenarios, in which the coal output cut is set from −3% to −10% respectively. Further, in order to observe whether the policy of cutting electric price will reduce the negative effects of action plan policy scenarios, the eight enhanced action plan policy scenarios were also set, in which the coal output cut is set from −3% to −10% respectively with the hypothetical electric price cut −3%. By using the developed computable general equilibrium (CGE) model, the policy scenarios are simulated, and the economic and environmental effects are tested. The results showed that: First, in most policy scenarios, the environmental and economic effects were changing synchronously in inverted U shapes, but the policy to cut coal output would lead to positive environmental effects and negative economic effects. Second, cutting electricity price could contribute to promoting electricity substitution, though it couldn't be conducive to improving the electricity structure. Third, the reduction of electricity price could also help to reduce the resistance in policy implementation. Consequently, for optimal environmental effects and economic resistance, it is recommended to set the policy target of cutting coal output as −6%, while the moderate reduction of electricity price is needed and set as −3%. Image 1 • Effects of environment-economic policy to cut coal output are assessed using CGE. • Cutting coal output will contribute to air pollution abatement to certain extent. • The policy intensities and their effect are not in linear sharps. • The proper policy intensity is selected by comprehensively comparing the effects. • Moderately and simultaneously reducing electricity price is beneficial and needed. [ABSTRACT FROM AUTHOR]

Metal pollution in the Bohai Sea in China has posed a potential risk on marine organisms. In this work, crabs (Portunus trituberculatus) were sampled from four sites, namely a reference (site 3934) and three metal-polluted (sites 6151, 6351, and 3562) sites, located in the Bohai Sea. Metal concentrations in crab gill tissues were measured using inductively coupled plasma mass spectrometry. Cu, Zn, and Cd in crab samples from S3562 presented the highest concentrations. Particularly, Cu concentration exceeded the marine biological quality standard II. Cd contents in crab samples from all metal-polluted sites exceeded the marine biological quality standard I. Nuclear magnetic resonance-based metabolomics indicated metal pollution-induced immune stresses in crab samples from all metal-polluted sites. Metal pollution in S6151 and S6351 disturbed energy metabolism through differential pathways. For crab samples from S3562, the metabolic profile suggested that metal pollution mainly induced osmotic stress. • Metal contents were tested in the crabs from four sites in the Bohai Sea in China. • Cu content in crab gills from S3562 exceeded marine biological quality standard. • Metabolomic analysis showed that metal pollution caused immune stress in crab gills. • Metal pollution in S6151 and S6351 affected energy metabolism in crab samples. • Metal pollution mainly induced osmotic stress in crab samples from S3562. [ABSTRACT FROM AUTHOR]

China is home to the world's largest cigarette maker, and with more than 320 million smokers, accounts for a fifth of world annual deaths from smoking-related diseases. Basic tobacco characteristics and its lead (Pb) and cadmium (Cd) contents of the 20 best-selling Chinese cigarette brands were detected using wet digestion-inductively coupled plasma mass spectrometry. Pb and Cd contents of the selected brands of cigarettes ranged from 1.3861 μg/g to 7.7124 μg/g and 2.9137 μg/g to 5.4841 μg/g, respectively, showing a significant correlation with tobacco weight per cigarette. Fuzzy health risk assessment via inhaling pathway of mainstream smoke was carried out for Pb and Cd based on the regional exposure parameters and fuzzification of the key variables. Results indicated the indexes of (non-)carcinogenic risk of tobacco Pb in all studied brands were below the corresponding general acceptable risk criteria, while that of tobacco Cd exceeded. Cd was identified as the priority control metal in the studied cigarettes. Moreover, the maximum membership probabilities of E08, E09, S11, S18 and S19 were in marginal range of 50%–60%, showing existed uncertainties and possibly misleading decision-makers. Spatially, the carcinogenic risks posed by regional cigarette Cd showed a relatively high level in the Southern, Southwestern and Northern China. Based on Level II for carcinogenic risk (1.00E-05), the limit daily consumption and limit concentration of Cd were obtained for each brand, and the result ranges were generally 2–4 cigarettes per day and 0.5–1.7 μg/g. Presently, it is of significance for the related international/local decision-makers to establish a comprehensive supervisory framework and system for Cd (and other typical toxic metals) in cigarettes from its life cycle perspective. Image 1 • 20 best-selling cigarette brands across the Chinese six regions were investigated. • Smoking health risk posed by tobacco Pb and Cd was assessed with fuzzy theory. • Cd in the selected cigarettes was found to pose certain health threats to smokers. • Regional limit concentrations for Cd were established on health risk guidelines. • Daily consumption limits were recommended according to the different brands. [ABSTRACT FROM AUTHOR]

Facing the challengeable PM2.5 pollution management across China, it is of significance to identify key pollution driving factors with a nation-region-city perspective and establish targeted joint management strategies on the trans-provincial scale. To identity hot study regions, the spatiotemporal pollution variation of PM2.5 in 2016 was explored using multi-scale spatial autocorrelation analysis based on the ground monitoring data for Chinese 366 cities. In the identified study regions, the relationship of natural factors and PM2.5 was analyzed on annual and daily scales via the correlation analyses, and the multiple socioeconomic driving forces of PM2.5 were identified utilizing geographic weighted regression (GWR) and principal component analysis. Consequently, 111 cities were identified as the hot regions, where their annual means of PM2.5 (AM) were 60.40 ± 14.23 μg·m−3 exceeding the Chinese level II standard and WHO Air Quality Guideline IT-1 (35 μg·m−3). The elevation and annual accumulative rainfall were found to be negatively correlated with the AM (p < 0.01). The increase of temperature and wind speed mainly helped daily PM2.5 reduce. Furthermore, the sensitive socioeconomic factors, mainly including the added value of the industry, the per capita gross domestic product and the per capital annual disposable income, were identified due to GWR. Then, based on the found spatial heterogeneity of sensitive factors, the selected 111 cities were identified into four types (Q 1 , Q 2 , Q 3 , Q 4) and two sub-regions, Q 1 +Q 2 (13+49 cities) and Q 3 +Q 4 (27+22 cities). Finally, for multi-scale environmental sustainability and equity, the joint management strategies were formulated for each cities pattern based on their feature of sensitive pollution driving forces and city role positioning. Image 1 • Spatiotemporal patterns of PM2.5 in 366 Chinese cities were explored on multi-scale. • Increase of elevation, rainfall/wind, temperature help annual/daily PM2.5 reduce. • PM2.5 was sensitive to social factors like Added value of industry, Per Capita GDP. • 111 hot cities were identified into four types on spatially heterogeneous features. • Joint management strategies were formulated for each kind based on driving factors. [ABSTRACT FROM AUTHOR]

Two novel strains, designated 11W25H-1T and 8H24J-4-2T, were isolated from surface-sterilized plant tissues collected from the Taklamakan Desert in the Xinjiang Uygur Autonomous Region, China. The strains were characterized by a polyphasic approach in order to clarify their taxonomic positions. They were Gram-stain positive, aerobic, non-motile, non-spore-forming and rod-shaped. The 16S rRNA gene sequences of the strains showed highest similarities with Labedella gwakjiensis KCTC 19176T (99.2% and 98.9%, respectively) and Labedella endophytica CPCC 203961T (98.9% and 99.0%, respectively). The sequence similarity between strains 11W25H-1T and 8H24J-4-2T was 99.4%. Phylogenetic analyses based on 16S rRNA gene sequences and single-copy phylogenetic marker genes (pMGs) showed that the two strains belonged to the genus Labedella and formed a separate cluster from the closest species L. gwakjiensis KCTC 19176T and L. endophytica CPCC 203961T. Genomic analyses, including average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH), clearly separated the strains from each other and from the other species of the genus Labedella with values below the thresholds for species delineation. The two strains showed chemotaxonomic characteristics and phenotypic properties in agreement with the description of the genus Labedella and also confirmed the differentiation from the closest species. The data demonstrated that strains 11W25H-1T and 8H24J-4-2T represented two novel species of the genus Labedella , for which the names Labedella phragmitis sp. nov. (type strain 11W25H-1T=JCM 33144T=CGMCC 1.16700T) and Labedella populi sp. nov. (type strain 8H24J-4-2T=JCM 33143T=CGMCC 1.16697T) are proposed. [ABSTRACT FROM AUTHOR]

Accurate and effective short-term wind power forecasting is vital for the large-scale integration of wind power generation into the power grid. However, due to the intermittence and volatility of wind resources, short-term wind power forecasting is challenging. To address the issue that the existing decomposition forecasting methods ignore the coupling relationship between wind power series and multiple meteorological series, this study proposes a short-term wind power forecasting method based on multivariate signal decomposition and variable selection. First, multivariate variational mode decomposition (MVMD) is used to perform time-frequency synchronous analysis on wind power and multidimensional meteorological series, thereby decomposing them into the same predefined number of frequency-aligned intrinsic mode functions (IMFs). Secondly, elastic net (EN) is used for supervised variable selection on all IMFs to provide a high-quality training set for the forecasting model, thereby enhancing precision and interpretability. Next, a hybrid deep neural network combining convolutional neural network (CNN), bidirectional long-short term memory (BiLSTM) neural network, and multi-head attention (MHA) mechanism is employed to model the output curve of a group of wind turbines in a wind farm. Finally, the proposed method is comprehensively evaluated through four sets of comparative experiments and multiple evaluation metrics on data gathered from the Mahuangshan first wind farm in China with four forecasting horizons: 15-min ahead, 30-min ahead, 45-min ahead, and 1-h ahead. The experimental results show that the proposed method significantly outperforms fifteen existing deep learning methods in terms of precision and stability. • A novel multivariate signal decomposition strategy is proposed for wind power forecasting. • Elastic net is firstly applied to provide a high-quality training set for the forecasting model. • Utilizing the multi-head attention mechanism to capture the long-term dependencies in wind power sequence. [ABSTRACT FROM AUTHOR]

China is the biggest tea producer in the world, and soils in the tea plantations play important roles in the carbon cycle, and regional and national carbon neutrality. The knowledge regarding the variation and the key drivers of soil organic carbon (SOC) stock in tea plantations could provide a scientific basis for assessing the potential of regional and national carbon sequestration and neutrality. This is also helpful for the sustainable management of tea plantations. However, little information is available on soil organic carbon (SOC) stock and influential factors in tea plantations. Thereby, SOC density (SOCD) and stock were estimated based on 1723 datasets collected from 322 published studies. Subsequent estimations reveal that the total SOC stock in China's tea plantations is 207.13 Tg with 124.58 Tg SOC stored in top soil layer (0–20 cm), and the average SOCD is 59.17 Mg ha−1 ranging from 0.9 Mg ha−1 to 589.54 Mg ha−1. The SOCD showed a significant three-dimension zonal pattern and was significantly influenced by managerial practices. Tea plantations managed in ecological ways and/or with long stand age even showed higher SOCD than that in neighbored forests. The lower average but wide range of SOCD in tea plantations indicates their great potential in carbon sequestration. This makes tea plantations critically important in regional and national carbon accounting and carbon neutrality, and cannot be ignored in future research and policymaking initiatives. • Total soil organic carbon (SOC) stock in China's tea plantations is 207.13 Tg. • The average SOC density in China's tea plantations is 59.17 Mg ha−1. • SOC density showed a significant three-dimension zonal pattern. • The SOC density was significantly influenced by managerial practices. • China's tea plantations have great potential in carbon sequestration. [ABSTRACT FROM AUTHOR]

• Low Fe transfer within the leaf was tightly correlated with Fe deficiency chlorosis. • High apoplastic pH enhanced Fe deposition near the leaf midrib of HG-QA in calcareous soil. • Low FCR activity inhibited Fe reduction in leaves of HG-QA in calcareous soil. • Rootstocks were involved in the regulation of leaf Fe utilization by scions. Quince (Cydonia oblonga Mill.) is a dwarfing rootstock often used in pear cultivation. However, the pear cultivar 'Huangguan' (Pyrus bretschneideri Rehd. cv) grafted onto quince A (HG-QA) suffered iron (Fe) deficiency chlorosis in the calcareous soils of North China, while 'Huangguan' grafted onto Pyrus betulifolia (HG-PB) did not. We hypothesized that the higher leaf apoplastic pH of HG-QA than HG-PB causes Fe deficiency chlorosis by restricting Fe transportation within leaves. Three-year-old rootstocks quince A and Pyrus betulifolia and the combinations HG-QA and HG-PB were grown in the same orchard in a calcareous soil. Newly expanded leaves were analysed for Fe related properties. Micro X-ray fluorescence analysis was used for Fe mapping within the individual leaves. The extractable Fe(II) concentrations in quince A and HG-QA leaves were much lower than those in Pyrus betulifolia and HG-PB, even though the total leaf Fe concentrations were similar. More Fe was located near the leaf midrib in quince A and HG-QA than in Pyrus betulifolia and HG-PB. These were correlated with the lower ferric chelate reductase (FCR) activity in the chlorotic leaves of the quince A rootstock than Pyrus betulifolia and the lower FCR activity and higher apoplastic pH in the chlorotic leaves of the HG-QA rootstock-scion combination than HG-PB. In conclusion, the reduced Fe availability within the leaves caused by the lower FCR activity and higher apoplastic pH compared with those of HG-PB led to HG-QA leaf chlorosis in calcareous soils. This result implies that rootstocks are involved in the regulation of leaf Fe utilization by scions. [ABSTRACT FROM AUTHOR]

This study recompiled a national dataset to characterize the pollution level and health risk of cadmium (Cd), copper (Cu), lead (Pb) and zinc (Zn) in oysters along the coastal areas of China. Results showed that the median concentrations of Cd, Cu, Pb and Zn in nationwide oysters were 5.5, 335, 1.3 and 1280 mg/kg dry weight, respectively. Generally, oysters from the north coasts presented lower metal pollution and higher quality than those from the south. The regional characteristics of trace metals in oysters might be contributed by the interspecific differences. Nationally, the noncarcinogenic risk posed by these four metals in oysters was relatively low, with the risk only occurring in a few hotspots such as the Pearl River Estuary and the Jiulong River Estuary. However, more attention should be paid to the carcinogenic risk of Cd, and priority should be given to formulating control measures to mitigate Cd pollution. [Display omitted] • A dataset of trace metals in oysters from 274 sites along Chinese coasts was recompiled. • Hotspots of metal pollution and associated human health risk in oysters were identified. • Trace metals in oysters nationwide did not pose widespread noncarcinogenic risk. • The human carcinogenic risk of cadmium in oysters nationwide should not be ignored. [ABSTRACT FROM AUTHOR]

Chinese children are exposed to broad environmental risks ranging from well-known hazards, such as pesticides and heavy metals, to emerging threats including many new man-made chemicals. Although anecdotal evidence suggests that the exposure levels in Chinese children are substantially higher than those of children in developed countries, a systematic assessment is lacking. Further, while these exposures have been linked to a variety of childhood diseases, such as respiratory, endocrine, neurological, behavioral, and malignant disorders, the magnitude of the associations is often unclear. This review provides a current epidemiologic overview of commonly reported environmental contaminants and their potential impact on children's health in China. We found that despite a large volume of studies on various topics, there is a need for more high-quality research and better-coordinated regional and national data collection. Moreover, prevention of such diseases will depend not only on training of environmental health professionals and enhanced research programs, but also on public education, legislation, and networking. [ABSTRACT FROM AUTHOR]

Both EU-DEMO and CFETR need a workable replacement scheme for their tritium breeding blanket (BB). The radioactive environment dictates that all associated operations must be carried out through remotely controlled tools. Accessing and extracting the large BB segments requires their feeding pipes to be removed first from the upper vessel port and later re-installed. In the current design, each of the 80 BB segments is connected with four feeding pipes, two for cooling and two for tritium extraction. Thus, in the process of BB maintenance operation, 320 pipes must be cut, removed and rewelded. The developed concept for this task is presented here. It aims at reducing the associated plant downtime, thereby increasing the overall plant availability. Features underpinning this integrated BB pipe service concept are: (i) parallel pipe service operations, (ii) pipes in each upper port are grouped in a pipe forest and handled as a single component, (iii) the configuration of the individual pipes is standardized such that cutting and joining locations are aligned and with good accessibility from the top, (iv) the number of pipe sizes is limited to two, reducing the number of required tool sets, and (v) the same pipe configuration is adopted in each of the 16 upper ports. The paper will present design solutions and the progress on the manufacturing of prototypes developed for the challenging cutting and welding tasks from both within and outside, as well as the leak detection methodology and pipe stub handling. Prototypes will be used to perform design validation and verification on dedicated test benches currently being implemented in close collaboration between European laboratories and the Comprehensive Research fAcility for Fusion Technology (CRAFT) at ASIPP in China. [ABSTRACT FROM AUTHOR]

• Different responses of soil respiration (R s) components to forest fire. • Soil heterotrophic respiration (R h) increased significantly in burned plots (24%). • Soil autotrophic respiration (R a) decreased significantly in burned plots (66%). • The ratio of R h to R s significantly increased in burned plots (39%). • Fire led to R s C efflux increased during the spring freeze–thaw cycles period (28%). • MBC (microbial biomass carbon) was the dominant biotic driver of R s in burned plots. Fire plays a critical part in regulating soil carbon (C) budgets in forest ecosystems. However, few studies have focused on the effects of fire on soil respiration (R s) and its heterotrophic (R h) and autotrophic (R a) components. In this study, we examined the response of R s , R h , and R a to fire and the driving factors that affect R s after a fire disturbance in a Dahurian larch (Larix gmelinii) forest in northeastern China. Fire disturbance significantly increased R h by approximately 24% and significantly reduced R a by approximately 66% in burned plots compared to unburned plots. The ratio of R h to R s significantly increased from 0.57 in the unburned plots to 0.79 in the burned plots. Fire disturbance also led to cumulative R s C efflux increasing by approximately 10% and 28% during the growing season and the period of spring freeze–thaw cycles (FTC) in the burned plots. Furthermore, using structural equation modelling, we showed that T 5 (soil temperature at 5 cm depth) was the main abiotic factor affecting R s in both unburned and burned plots. Fine root biomass (FR) was the dominant biotic driver of R s in the control plots, whereas microbial biomass carbon (MBC) was the dominant biotic driver of R s in burned plots. Our findings demonstrated a significant discrepancy in the response of R s components to fire disturbance. Forest fires can cause considerable losses of soil C in a cold temperate forest ecosystem, which suggests that proactive management of forest regeneration should be carried out after forest fire disturbances. [ABSTRACT FROM AUTHOR]

Heart transplantation (HTx) remains the gold-standard treatment for end-stage heart failure. The aim of this study was to establish a risk-prediction model for assessing prognosis of HTx using machine-learning approach. Consecutive recipients of orthotopic HTx at our institute between January 1st, 2015 and December 31st, 2018 were included in this study. The primary outcome was 1-year mortality. Least absolute shrinkage and selection operator method was used to select variables and seven different machine-learning approaches were employed to develop the risk-prediction model. Bootstrap method was used for model validation. Shapley Additive exPlanations (SHAP) method was used for model interpretation. 381 recipients were included with average age of 43.783 years old. Albumin, recipient age and left atrium diameter ranked top three most important variables that affected the 1-year mortality of HTx. Other important variables included red blood cell, hemoglobin, lymphocyte%, smoking history, use of lyophilized rhBNP, use of Levosimendan, hypertension, cardiac surgery history, malignancy and endotracheal intubation history. Random Forest (RF) model achieved the best area under curves (AUC) of 0.801 and gradient boosting machine (GBM) showed the best sensitivity of 0.271. SHAP method was introduced to display the RF model's predicting processes of "survival" or "death" in individual level. We established the risk-prediction model for postoperative prognosis of HTx patients by using machine learning method and demonstrated that the RF model performed the highest discrimination with the largest AUC when validated. This prediction model could help to recognize high-risk HTx recipients, provide personalized therapy plan and reduce organ wastage. • Used ML approaches to establish prediction model in Chinese HTx population. • Applied seven ML models and figured out RF model outperformed other models. • Introduced SHAP method to visualize the process of how ML models came to a decision. [ABSTRACT FROM AUTHOR]

• A lateral flow strip combined with recombinase polymerase amplification (LF-RPA) assay was developed to detect HBV The LF-RPA assay demonstrated well specificity and sensitivity. • The LF-RPA assay provides an affordable diagnostic tool for detection of HBV. • The LF-RPA assay could detect most of the circulating HBV strains in China. Hepatitis B virus (HBV) infection is a major public health priority. In the present study, a lateral flow strip combined with the recombinase polymerase amplification (LF-RPA) assay was developed and evaluated for rapid HBV detection. A primer/probe pair targeting the conserved region of the HBV genome was designed and applied to the LF-RPA. TheRPA was achieved at the isothermal temperature of 39℃ for 30 min, and the RPA products were detected using the LF test. DNA extraction, RPA reaction and endpoint detection will take about 70 min. The LF-RPA assay could detect HBV at as low as 10 copies/reaction, with no cross-reactions with other common pathogens. The LF-RPA assay was performed on 85 samples. Of these, 36 samples tested HBV positive, whereas 49 were negative. Similar results were obtained using the conventional polymerase chain reaction method. Thus, the newly developed LF-RPA assay can be an improved diagnostic tool for rapid and simple HBV detection. [ABSTRACT FROM AUTHOR]

The accumulation of extracted titanium tailing (ETT) has seriously affected the local environment and human healthcare in the Panxi area of southwestern China. This research provides a practical way to convert ETT (up to high amount of 50 wt%) to high performance glass-ceramic by introducing waste glass (WG). The effects of sintering temperature and heat-treatment duration on the micro-structures and physicochemical properties of the produced glass-ceramic have been systematically investigated. It is found that the crystalline phase of the glass-ceramic has a great influence on the linear shrinkage rate and bulk density, further affecting its water absorption rate and hardness. The optimal product shows enhanced physical properties: linear shrinkage rate of 17.40 ± 0.04 %, bulk density of 2.75 ± 0.02 g cm-3, Vickers hardness of 21.3 ± 0.2 GPa and water absorption rate of 0.060 ± 0.002 % at the optimized sintering conditions. The formation mechanism of recycling two industrial wastes provides a guidance function to synthesize glass-ceramic using similar industrial waste residue and tailings. The obtained glass-ceramic with high performance has potential to be applied extensively in construction and building field. [ABSTRACT FROM AUTHOR]

Background: Whether extended lymphadenectomy for right colon cancer leads to increased perioperative complications or improves survival is still controversial. This trial aimed to compare the efficacy and safety of complete mesocolic excision (CME) versus D2 dissection in laparoscopic right hemicolectomy for patients with right colon cancer. This article reports the early safety results from the trial.Methods: This randomised, controlled, phase 3, superiority, trial was done at 17 hospitals in nine provinces of China. Eligible patients were aged 18-75 years with histologically confirmed primary adenocarcinoma located between the caecum and the right third of the transverse colon, without evidence of distant metastases. Central randomisation was done by means of the Clinical Information Management-Central Randomisation System via block randomisation (block size of four). Patients were randomly assigned (1:1) to CME or D2 dissection during laparoscopic right colectomy. Central lymph nodes were dissected in the CME but not in the D2 procedure. Neither investigators nor patients were masked to their group assignment but the quality control committee were masked to group assignment. The primary endpoint was 3-year disease-free survival, but the data for this endpoint are not yet mature; thus, only the secondary outcomes-intraoperative surgical complications and postoperative complications within 30 days of surgery, graded according to the Clavien-Dindo classification, mortality (death from any cause within 30 days of surgery), and central lymph node metastasis rate in the CME group only-are reported in this Article. This early analysis of safety was preplanned. The outcomes were analysed according to a modified intention-to-treat principle (excluding patients who no longer met inclusion criteria after surgery or who did not have surgery). This study is registered with ClinicalTrials.gov, NCT02619942. Study recruitment is complete, and follow-up is ongoing.Findings: Between Jan 11, 2016, and Dec 26, 2019, 1072 patients were enrolled and randomly assigned. After exclusion of 77 patients, 995 patients were included in the modified intention-to-treat population (495 in the CME group and 500 in the D2 dissection group). The postoperative surgical complication rate was 20% (97 of 495 patients) in the CME group versus 22% (109 of 500 patients) in the D2 group (difference, -2·2% [95% CI -7·2 to 2·8]; p=0·39); the frequency of Clavien-Dindo grade I-II complications were similar between groups (91 [18%] vs 92 [18%], difference, -0·0% [95% CI -4·8 to 4·8]; p=1·0) but Clavien-Dindo grade III-IV complications were significantly less frequent in the CME group than in the D2 group (six [1%] vs 17 [3%], -2·2% [-4·1 to -0·3]; p=0·022); no deaths occurred in either group. Of the intraoperative complications, vascular injury was significantly more common in the CME group than in the D2 group (15 [3%] vs six [1%], difference, 1·8 [95% CI 0·04 to 3·6]; p=0·045). Metastases in the central lymph nodes were detected in 13 (3%) of 394 patients who underwent central lymph node biopsy in the CME group; no patient had isolated metastases to central lymph nodes.Interpretation: Although the CME procedure might increase the risk of intraoperative vascular injury, it generally seems to be safe and feasible for experienced surgeons.Funding: The Capital Characteristic Clinical Project of Beijing and the Chinese Academy of Medical Sciences. [ABSTRACT FROM AUTHOR]

Heart transplantation (HTx) of brain-dead donors in China has not been reported, not to mention analysis of donors with different brain death mechanisms. The present study aimed to compare clinical outcomes between HTx of traumatically brain-injured (TBI) and non-TBI donors, as well as to establish a risk-prediction model of mortality. All patients undergoing HTx at our institute between January 1st, 2015 and December 31st, 2018 were dichotomized according to cause of donor death, and outcomes between the two groups were compared based on propensity score matching (PSM). The primary endpoint was all-cause mortality. Secondary endpoints included cardiac allograft vasculopathy and other postoperative complications. 342 eligible HTx recipients were included. TBI grafts accounted for 62.87% (215/342). 121 pairs of candidates were generated from PSM. Actuarial and risk-adjusted survival were similar between TBI and non-TBI groups. Risk factors associated with all-cause mortality included recipient age > 60y (HR = 2.781, p =.002), history of cardiac surgery (HR = 2.186, p =.032), chronic kidney disease (HR = 2.948, p =.033) and smoking (HR = 0.465, p =.041), as well as donor age > 45y (HR = 2.701, p =.003) and BMI > 25 kg/m2 (HR = 2.025, p =.045). The risk-prediction model was established successfully based on specific preoperative variables and high-risk group with a score>10 had nearly fourfold increase in mortality (HR = 3.726, p < 0.001) compared to the low-risk group. In this largest single-center cohort from China, we found similar survival and rates of complications between HTx recipients with TBI and non-TBI donors. The risk-prediction model may help to identify high-risked recipients and donors and optimize organ-sharing. • Used propensity score matching to increase comparability. • Reported results in heart transplantation using brain death donors from China. • Established a risk-score model to predict heart transplantation recipients' prognosis. [ABSTRACT FROM AUTHOR]

Iatrogenic biliary injury (IBI) following laparoscopic cholecystectomy (LC) is the most serious iatrogenic complications. Little is known whether LC-IBI would lead to surgeon's severe mental distress (SMD). A cross-sectional survey in the form of electronic questionnaire was conducted among Chinese general surgeons who have caused LC-IBI. The six collected clinical features relating to mental distress included: 1) feeling burnout, anxiety, or depression, 2) avoiding performing LC, 3) having physical reactions when recalling the incidence, 4) having the urge to quit surgery, 5) taking psychiatric medications, and 6) seeking professional psychological counseling. Univariable and multivariable analyses were performed to identify risk factors of SMD, which was defined as meeting ≥3 of the above-mentioned clinical features. Among 1466 surveyed surgeons, 1236 (84.3%) experienced mental distress following LC-IBI, and nearly half (49.7%, 614/1236) had SMD. Multivariable analyses demonstrated that surgeons from non-university affiliated hospitals (OR:1.873), patients who required multiple repair operations (OR:4.075), patients who required hepaticojejunostomy/partial hepatectomy (OR:1.859), existing lawsuit litigation (OR:10.491), existing violent doctor–patient conflicts (OR:4.995), needing surgeons' personal compensation (OR:2.531), and additional administrative punishment by hospitals (OR:2.324) were independent risk factors of surgeon's SMD. Four out of five surgeons experienced mental distress following LC-IBI, and nearly half had SMD. Several independent risk factors of SMD were identified, which could help to make strategies to improve surgeons' mental well-being. [ABSTRACT FROM AUTHOR]

• High geostress and horizontal joint condition affect the squeezing condition. • Resistant support might be failed in squeezing ground. • A simple and economic tangential yielding element is proposed. • The developed tangiential yielding elment is efficient in cope with squeezing ground. Squeezing problems pose a serious challenge for tunnel engineers because they can slow down a project, increase the project budget, and potentially lead to catastrophic collapse. The choice of an adequate support is also often difficult owing to complex geological environments. Lack of sufficient understanding of geological conditions such as high geostress and horizontal layered rock mass could cause tunnel collapse and further lead to economic loss and endanger human life. In an attempt to deal with in-situ squeezing problem, this paper focus on the investigation of the mechanical behavior of tunneling in horizontal layered rock mass with high geostress and the proposal of proper engineering measures. A tunnel collapse incident occurred in northeastern China is analyzed using comprehensive methods including photographing, laboratory tests, discrete element numerical simulations, and site monitoring. The discrete element method was applied to investigate the tunneling mechanical behavior under high-geostress conditions in a horizontally layered rock mass. Numerical simulations show that the dominant horizontal stress and joints cause the maximum deformation at the corner of the arch region. The effect of horizontal joints and horizontal dominant stress were analyzed and found to be the main causes of the collapse. Based on the simulation results, an innovative, simple and efficient tangential yielding element is developed and implemented to test its applicability in a tunnel engineering scenario. Load-displacement curves of the tangential yielding element were obtained through laboratory tests and introduced to the numerical model using the 3D discrete element method. The performance of the developed tangential yielding element was validated in the simulation. Site monitoring was also conducted to determine the in-situ performance of the yielding support using the tangential yielding element. The monitored settlement at the crown region is in agreement with the simulation. The in-situ tests show that the yielding element was considerably deformed while the tunnel remained stable, which confirms the applicability of this technique. The effectiveness of the yielding element is also confirmed in terms of a comparative cost analysis of the yielding and resistant support schemes. [ABSTRACT FROM AUTHOR]

• It was the first time to investigate sources and risks of soil heavy metals completely in the study area. • Four sources of soil heavy metals in a typical agricultural county were identified mainly by PMF model. • Agricultural activities were subdivided into two types of sources for research. • The impacts of each pollution source and each metal on ecological risks were quantitatively and spatially analyzed. This study collected topsoil samples from 330 sites of Shan County, a typical Chinese agricultural county, to analyze the causes and effects of heavy metal pollution. It was found that the average contents of all heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) were lower than their screening values in China. However, average contents of As, Cd, Hg, Ni, and Zn exceeded their local background level. The enrichment factors suggested the moderate pollution of Cd and slight pollution of Hg, and they were also the two of the most toxic elements. Most importantly, a new combination of spatial analysis, ecological risk assessment and positive matrix factorization model was used to identify the sources and ecological risks of heavy metals from different sources quantitatively and spatially. The results showed that the risk contribution rates of the natural source, sewage irrigation and animal husbandry, atmospheric deposition and industrial emissions, and agricultural materials were 20.0%, 35.1%, 22.0% and 22.9%, respectively. It was worth noting that agricultural activities contributed nearly 60% of the risk. In general, a large part of the area was in moderate risk. Therefore, it was necessary to promote long-term control of major sources and take precautions. [ABSTRACT FROM AUTHOR]

Pancreatic cancer (PC), one of the most lethal malignancies, accounts for 8%-10% of digestive system cancers, and the incidence is increasing. Surgery, chemotherapy, and radiotherapy have been the main treatment methods but are not very effective. However, only 20% of patients have the opportunity to undergo surgical operation. Approximately 30-40% of patients present with locally advanced, unresectable pancreatic cancer because of invasion of mesenteric vessels or adjacent organs. The first patient with unresectable pancreatic cancer was treated with Intraoperative radiotherapy (IORT) in 1959 [1]. Since then, new surgical and radiotherapeutic techniques have been developed, clinical trials have provided new evidence, and intriguing long-term effects have emerged from global metadatabases. IORT has the advantages of more accurate target, better local control rate, less complications, longer survival time and better life quality. During the past decade, IORT has been applied in some hospitals in the world, but there is little agreement on technical details and standards. A guidelines of IORT in pancreatic cancer is therefore necessary and timely. To develop standardized criteria for the application of IORT in pancreatic cancer, the experts from China to discuss treatment methods and arrive at a consensus on the indications, contraindications, and preferred techniques of IORT in pancreatic cancer. This detailed and agreed technical description of IORT may have implications on training, assessment, quality control, and future research. [ABSTRACT FROM AUTHOR]

[Display omitted] • Large fracture-cavity reservoirs in fault damage zones are typically found at distances ranging from150 m to 800 m away from fault zone. • Reservoirs adjacent to the 'X' shear strike-slip fault are better developed. • Fault-controlled carbonate reservoirs are mainly formed in buried-hill karst stage. To reveal the effect of faults in the deep and ultra-deep oil and gas reservoirs, based on the comprehensive analysis of drilling logs and the core and seismic data, the development and fault-controlled regularity of the reservoirs in the high and low inner part of the Ordovician carbonate of the Tabei paleo-uplift have been discussed. The results show that large fracture-cave reservoirs are developed in the Tabei paleo-uplift, and as main reservoir, the cave-type reservoirs usually appeared as lumps or patches in the north of the pinch-out line of O 3 s , and gradually transitioned to isolated dots to the south. Due to the difference in control effect of faults, the degree of reservoir development differs greatly from north to south. The effective reservoir thicknesses are relatively stable and the porosity are relatively high in north, which are mainly controlled by karst and fractures, and the effect of faults on reservoir is not obvious. To the south, the reservoirs are gradually banded along the fault, and the control effect of large strike-slip faults are enhanced. This indicates that the strike-slip faults are more important to the development of reservoir in the low inner part. This difference is caused by the differences in fault controlling factors during different evolution periods of the paleo-uplift. [ABSTRACT FROM AUTHOR]

The intensive energy consumption in urban sectors is aggravating global warming, which triggers an in-depth thinking about energy-carbon nexus and low-carbon city actions. Hence, China has launched a pilot low-carbon city program to explore low-carbon pathways since 2010. This study employed a Long-range Energy Alternatives Planning System model (LEAP) to simulate six energy sectors-related GHG emissions in a pilot low-carbon Ningbo city, China. The LEAP-Ningbo model comprises three basic modules, i.e. energy supply, energy transformation and end-use energy demand in six urban sectors (i.e., household, service, agriculture, transport, industry, and transformation sectors), and resulting environmental impacts (CO 2 equivalents). The results identified by the business as usual (BAU) scenario indicate that total energy consumption is expected to reach 449.72 Mtce and results in emissions of 651.83 Mt CO 2e by 2050. In contrast, more aggressive policies and strategies involved in the integrated scenario (INT), which combines the energy structure optimization (ESO) scenario with the policy-oriented energy saving (PES) scenario, can lower energy demand by 14% and CO 2e emissions by 27%. A comparison among global cities and low-carbon plans helps identify the carbon emission level and define the actionable low-carbon policies. The high correlation between sectoral energy use and resulting GHG emissions implies energy-carbon reduction efforts, e.g., low-carbon energy substitution, intensive energy-saving policies, the improvement of energy efficiency, and industrial transformation. Achieving low-carbon city targets requires timeline-restricted actions and backgrounds-based measures in plans. The results of this study shed light on if and how cities can shape energy-carbon reduction trajectories and develop low-carbon pathways in China and beyond. [ABSTRACT FROM AUTHOR]

The process-based Biome-BGC (BioGeochemical Cycles) model is widely used to simulate the storage and flux of water, carbon, and nitrogen within an ecosystem. However, the Biome-BGC model neglects the existence of underground persistent portion of perennial grasses as well as functional differences between the fast-cycling and persistent roots, which are assumed to negatively impact the accurate estimation of net primary productivity (NPP) of alpine meadow on the Qinghai-Tibet Plateau. This study presents the Perennial Deciduous Grasses (PDG) NPP model developed under the framework of Biome-BGC version 4.2. In the PDG NPP model, underground roots of perennial grasses were partitioned into two portions, the fast-cycling portion and the persistent portion. These two portions were represented by different turnover fractions, carbon to nitrogen ratios, and allocation ratios in the PDG NPP model. Processes primarily involving allocation, maintenance respiration, growth respiration, litterfall and mortality, and transfer growth were modified to account for the differences between fast-cycling and persistent roots. Measured NPP including both aboveground NPP (ANPP) and belowground NPP (BNPP) at Zhenqin Station in Qinghai Province, China, was used to validate estimates of the PDG NPP model. The results showed that the PDG NPP model has a higher estimation accuracy of NPP than the Biome-BGC model. The root mean square error (RMSE) and mean absolute percent error (MAPE) of total NPP estimated from the PDG NPP model were 15.1 gC/m 2 /yr and 12.1%, respectively, whereas those from the Biome-BGC model were 49.8 gC/m 2 /yr and 39.9%, respectively. Both RMSE and MAPE of ANPP and BNPP estimates based on the Biome-BGC model were approximately 3 times those based on the PDG NPP model. Improvements of NPP estimation were mainly attributed to the decreasing estimates of gross primary productivity which was caused by the increase of water stress and decrease of soil N availability simulated during growing seasons. Therefore, the PDG NPP model is more reflective of the limitations of water and nutrients to vegetation growth and productivity when applied to the Qinghai-Tibet Plateau. [ABSTRACT FROM AUTHOR]

Maceriate reefs, characterized by centimeter- to decimeter-scale branching structures, flourished during the Cambrian to Early Ordovician on Laurentia, and Gondwana (the North China Platform). Dendritic and columnar maceriate reefs were newly discovered from the northwestern and central parts of the North China Platform. The maceria structures are composed of sponges (e.g., keratosans and lithistids) and microbial components, including Girvanella , Renalcis , and Tarthinia , whereas the interstitial material consists of lime mud with bioclasts and intraclasts. The first appearance of maceriate reefs was diachronous across the North China Platform, younging from the northwest (Drumian Age, Miaolingian) to the southeast (Jiangshanian Age, Furongian). In general, thrombolites and dendrolites were dominant in the microbialite-dominated reefs of the Miaolingian and microbe–sponge maceriate reefs were dominant in the Furongian. This dramatic shift to microbe–metazoan reef assemblages resulted from a combination of factors associated with the Miaolingian–Furongian boundary interval, including global transgression and a shift from widespread anoxia of the SPICE event to more oxygenated post-SPICE conditions. The North China examples suggest that sea level and paleoenvironmental conditions may have played a major role in this transition and its timing. • Newly discovered dendritic and columnar maceriate reefs from the North China Platform. • Diachronous occurrence of maceriate reefs across the NCP, younging from the northwest to the southeast. • Paleoenvironmental conditions as a major controlling factor for the spatio-temporal distribution and reef transition. [ABSTRACT FROM AUTHOR]

The spatial and temporal multi-scaling behaviors between the daily Air Temperature (AT) and the Surface Temperature (ST) over China are compared in about 60-yr observations by Multi-fractal Detrended Fluctuation Analysis (MF-DFA) method. The different fractal phenomena and diversity features in the geographic distribution are found for the AT and ST series using MF-DFA. There are more multi-fractal features for the AT records but less for ST. The respective geographic sites show important scaling differences when compared to the multi-fractal signatures of AT with ST. An interval threshold for 95% confidence level is obtained by shuffling the AT records and the ST records. For the AT records, 93% of all observed stations shows the strong multi-fractal behaviors. In addition, the multi-fractal characteristics decrease with increasing latitude in South China and are obviously strong along the coast. The multi-fractal behaviors of the AT records between the Yangtze River and Yellow River basin and in most regions of Northwest China seem to be weak and not significant, even single mono-fractal features. However, for the ST records, the geographical distributions of multi-fractal phenomenon seem to be in disorder which account for 81% of the stations. The weak multi-fractal behaviors of the ST records are concentrated in North China, most regions of Northeast China. [ABSTRACT FROM AUTHOR]

The tetragonal lattice structure enables cassiterites to incorporate dozens of elements within their crystal lattice (e.g. , Fe, Ti, W, Zr, Hf, Ta, Nb, Mn, Sc, V and Sb). Thus, it is anticipated that variations of these elements should record information of potential elemental substitution mechanisms and precipitation environments of cassiterites. With moderate amounts of U and Pb, cassiterites can be dated with U-Pb geochronology. In this study we collected cassiterite grains from six different ore types within the Gejiu tin polymetallic deposit to perform LA-ICP-MS U-Pb dating, multiple element mapping and in-situ trace element analysis. Systematic U-Pb dating of such cassiterites yielded Tera-Wasserburg lower-intercepted ages ranging from 81.91 ± 0.62 to 85.7 ± 1.4 Ma, coinciding, within their respective analytical uncertainties, with zircon U-Pb ages of regional Late-Yanshanian granitoids. Such age coincidence, combined with spatial association, suggests that tin mineralization may be genetically related to the late Cretaceous granitic magmatism. Multi-elemental mapping shows that the distribution of Nb, Ta, and Ti in the cassiterite grains correlate well with the regular oscillatory zoning patterns in Cathodoluminescence (CL) images. The relatively high Fe, Ga, Sb, W and U concentrations control the dark luminescing domains in these cassiterite grains. The systematic variations in chemical compositions suggest that trace elements such as Sc, V, Fe and Ga incorporate in cassiterites via coupled substitutions of Sc3+ + V5+ ↔ 2 (Sn, Ti)4+, Fe3+ + Ga5+ ↔ 2 (Sn, Ti)4+ and Fe3+ + OH−↔ Sn4+ + O2− or Fe3+ + H+↔ Sn4+. The covariation of redox sensitive elements such as Fe, Sb, W and U indicates that only 'tin-granite'-type cassiterites were formed under an oxidized state whereas cassiterites from other ore types were precipitated in a reducing environment. [Display omitted] [ABSTRACT FROM AUTHOR]

Current cap carbonate formation models invoke a number of different alkalinity sources for the Neoproterozoic deglacial ocean (e.g., weathering alkalinity, hydrothermal alkalinity, microbial sulfate reduction (MSR) alkalinity, and methane oxidation alkalinity). Assessment of the competing models depends in part on an evaluation of their proposed alkalinity source(s). In the Nanhua rift basin of South China, recently discovered Sturtian cap carbonates on horsts have the potential to address this issue owing to sedimentological and geochemical differences between them and correlative deepwater deposits from adjacent grabens. Cap carbonates at three sites in northeastern Guizhou Province, China were selected for petrographic, XRD, XRF, ICP-MS, in-situ LA-ICP-MS, and Sr and Nd isotope analyses to evaluate the conditions and processes under which they formed: (1) JJS, a high-energy shallow-water (platform) setting that accumulated white laminated dolostone and pisolitic grainstone, (2) ZK01, an intermediate-depth (upper slope) setting that accumulated dark-gray laminated dolostone, and (3) ZK4207, a deep-water (basinal) setting that accumulated organic-rich Mn‑carbonates of the basal Datangpo Formation. The salinity proxy B/Ga records brackish conditions at JJS (4.7 ± 1.2) versus fully marine conditions at ZK01 (7.5 ± 0.8) and ZK4207 (9.1 ± 2.0). Hydrothermal influences, as proxied by high Eu/Eu*, trace-metal (Co, Ni, Cu, V) enrichments, and radiogenic Sr Nd isotopic compositions, were strong in the latter sections but absent at JJS. These observations document the existence in the post-Sturtian Nanhua Basin of a reduced-salinity surface layer presumably containing a large glacial meltwater component and lacking hydrothermal inputs, and a fully marine deep watermass subject to strong hydrothermal inputs. Carbonate δ13C variation between JJS (−2 to +2‰), ZK01 (−4 to 0‰), and ZK4207 (−7 to −6‰) records a pronounced vertical carbon-isotope gradient in the Nanhua Basin, consistent with elevated marine productivity in the context of strong salinity/density stratification. Massive inputs of alkalinity from meltwater sources are supported by a ∼ 3.5× greater flux to surface-layer dolomitic cap carbonates than to basinal Mn‑carbonates during the Sturtian deglaciation, although strong correlations between intermediate/deep-water carbonates and hydrothermal proxies imply that basin-floor vents were an additional source of alkalinity. Our study provides insight into the mechanisms of formation of cap carbonates generally, with implications for both Sturtian and Marinoan cap carbonate deposits on other cratons. • New mineralogical and geochemical data from Sturtian cap carbonates, Guizhou, China • Strongly stratified watermass structure existed during cap carbonate deposition. • Surface waters had reduced salinity owing to massive glacial meltwater runoff. • Deep waters were of marine salinity with strong hydrothermal influences. • Alkalinity in Nanhua Basin sourced from both glacial meltwater and hydrothermal vents. [ABSTRACT FROM AUTHOR]