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We investigated the inter-day effects of price limits policies that are employed in agent-based simulations. To isolate the impact of price limits from the impact of other factors, we built an artificial stock market with higher frequency price limits hitting. The trading mechanisms in this market are the same as the trading mechanisms in China’s stock market. Then, we designed a series of simulations with and without price limits policy. The results of these simulations demonstrate that both upper and lower price limits can cause a volatility spillover effect and a trading interference effect. The process of price discovery will be delayed if upper price limits are imposed on a stock market; however, this phenomenon does not occur when lower price limits are imposed. [ABSTRACT FROM AUTHOR]

Two large earthquakes occurred in the western part of China in 2008, one of them being the Yutian (35.6°N, 81.6°E) M7.3 earthquake that occurred on March 21 (BJT) and the other the Wenchuan (31.0°N, 103.4°E) M8.0 earthquake that occurred on May 12 (BJT). In this paper, the West Continental China (included in 20.0°-50.0°N, 70.0°-110.0°E region) was the study region for verifyong the predictability of the pattern informatics (PI) method using the receiver-operating characteristic curve (ROC) test and R score test. Different forecasting maps with different calculating parameters were obtained. The calculating parameters were the grid size Δ x, base time t, reference interval t to t, change interval t to t, and forecasting interval t to t. In this paper, the base time t fixed to June 1, 1971, the ending forecast time t fixed to June 1, 2008, and the forecasting interval t to t changed from 1 to 10 years, and the grid sizes were chosen as 1° × 1° and 2° × 2°, respectively. The results show that the PI method could forecast the Yutian M7.3 and Wenchuan M8.0 earthquakes only using suitable parameters. Comparing the forecast results of grid sizes 1° × 1° and 2° × 2°, the models with 2° × 2° grids were better. Comparing the forecast results with different forecasting windows from 1 to 10 years, the models with forecasting windows of 4-8 years were better using the ROC test, and the models with forecasting windows of 7-10 years were better using the R score test. The forecast efficiency of the model with a grid size of 2° × 2° and forecast window of 8 years was the best one using either the ROC test or the R score test. [ABSTRACT FROM AUTHOR]

Abstract: Crop reference evapotranspiration (ET 0) is often used to determine crop water requirement. ET 0 maps are useful for regional agricultural and water resources management, and also play an important role in the distributed hydrological modeling. For generating spatial ET 0 surfaces, ‘Interpolate-then-calculate (IC)’ approach is powerful in principle and is recommended especially for sparse weather station networks. The partial thin-plate smoothing spline incorporated in ANUSPLIN for interpolating climatic variables has been accepted widely across the world. In this paper, the climatology monthly ET 0 data of Shiyang river basin, one of the three inner basins in northwest China, are developed by spatially modeling the input climatic parameters with ANUSPLIN, and from the interpolated climate and ET 0 datasets, sensitivity coefficients of ET 0 to the climatic variables of selected months are also spatially distributed. In the cool months (January, February, November and December), the spatial variability of ET 0 is small and the value is rather low, whereas the warm season (May, June, July and August) is characterized by high values of ET 0 and large spatial variations in the river basin. Vapor pressure deficit is the most sensitive variable during the cool months and in the mountainous area with lower temperature; mean air temperature is the least sensitive one during the year and a little variation is observed at the basin scale. In summer, available energy primarily forces ET 0 as expected, and in winter, wind speed plays an important role and affects ET 0 greater at the northern plain region where deserts are dominated by dunes and low shrubs. We conclude that for regions with isolated climate stations, ‘IC’ procedure by including topographic and geographic factors can effectively model spatially distributed ET 0. [Copyright &y& Elsevier]

In order to accurately assess the thermal maturity of highly/over-mature shales in Paleozoic strata in southern China, hydrothermal experiments of shale samples from the Dalong Formation from bed 18 of well-exposed Shangsi PTB Section was conducted in a semi-open system under various conditions of geological constraint. The saturated extracts of pyrolyzed shale samples were subjected to gas chromatography and mass spectrometry (GC-MS) analyses. The results indicated that hydrothermal experiments of Dalong shales in the presence of fluid pressure (FP), lithostatic stress (LS), water, catalyst of clay minerals and trace elements, is partially equivalent to catalytic hydropyrolysis in terms of the catalytic hydrogen effect for the release of bound biomarkers from geomacromolecules of kerogen and asphaltene. The evolutional trend of maturity-related biomarkers were classified into the following three categories: (a) the most common maturity parameters (e.g., Ts/(Ts + Tm) and C 29 S/(S + R)) initially increased and then decreased with a pyrolysis temperature (450 °C) at the reversal point during maturation; (b) the parameters (e.g., C 32 S/(S + R)) primarily increased or decreased and reached a temperature (400 °C) of tuning point, and then remained unaltered with increasing temperature (c) the parameters (e.g., C 27 DS/S); firstly increased, and then declined at a specific turning point temperature (425–500 °C), and thereafter continued to increase until the end of heating process. As a result, the threshold temperature for the release of bound sterane or terpane occurred in the range 400–500 °C. Most maturity-related sterane and terpane biomarker parameters cannot be applied to evaluate the maturity of highly/over-mature shale. However, the C 30 M/C 30 H ratio and S/T ratio, which are strongly correlated with temperature, may be employed to assess extremely mature shale from these Paleozoic strata due to the integrated effects of multiple factors in the thermal evolution process of biomarkers. This is very important for the exploration and development of shale gas in southern China. Additionally, the values of several source-related biomarker parameters derived from C 27–29 regular steranes are relatively constant during maturation, such as the ternary plot of the C 27–29 αααR sterane versus the C 27 /C 29 αααR sterane ratio. These are useful indicators for distinguishing the genetic source of highly/over-mature shales. • Hydrothermal experiment of Dalong shales under geological constraint is partially equivalent to catalytic HyPy. • C 30 M/C 30 H ratio and S/T ratio may be employed to assess extremely mature shale from Paleozoic strata in southern China. • Source-related biomarker parameters derived from C 27–29 regular steranes could be useful for highly/over-mature shales. [ABSTRACT FROM AUTHOR]

Using the stock transaction records of individual investors from a large brokerage firm in China, we explore the impact of Confucian culture on the gambling preferences of individual investors. After a series of tests, we find a significant negative relationship between Confucianism and the lottery-type stock preference of individual investors, indicating that Confucian culture inhibits gambling preferences in stock investment. This effect is more pronounced for female investors, middle-aged investors and investors in regions with higher gambling sentiment. Investor risk preference mediates the relationship between Confucian culture and lottery-type stock preference. • The impact of Confucian culture on the gambling preferences of individual investors is explored. • Our sample incudes the stock transaction records of individual investors in China. • Confucian culture inhibits individual's gambling preference in stock market investment. • Investor risk preference mediates this relationship. • This effect is more pronounced for female investors, and middle-aged investors. [ABSTRACT FROM AUTHOR]

• A vulnerability analysis for vegetation cover in an inland river basin is developed. • The severe drought events over the basin are identified for the period 2001–2010. • Time-lags of irrigated and non-irrigated vegetation to soil water are quantified. • The proposed approach serves to assess regional eco-environmental vulnerability. Evaluating the relationship between the vegetation conditions on both non-irrigated (rain-fed) and irrigated lands with the soil water availability at a river basin scale is particularly important, as they address the breadth of vulnerability sources and concentrate on a dominant water factor which reflects the physical processes. A four-step framework is proposed to study the vegetation responses to natural soil water content. Three severe drought events for an inland river basin, the Heihe River basin in Northwest China, are identified for the period of 2001–2010. The severe events occurred within the period from June to September and often lasted about 1–2 months. The time-lags of irrigated and non-irrigated vegetation cover to soil water evolutions are found respectively, ranging from approximately −80 to +80 days, which are associated with regional eco-environmental vulnerability. The negative lags, indicating water deficit for crops, mostly occurred in the eastern part of midstream of Heihe River with farmland. The positive lags mainly appeared at the western part of headwater regions of Heihe River. The efforts to assess the vulnerability of regional vegetation to drought in the context of climate change offer guidance to natural environment and agricultural managements in allocating available water particularly under drought situations. [ABSTRACT FROM AUTHOR]

The aims of the present study were to use Langmuir Probe payload electron density data and Plasma Analyzer Package payload O+ density data from the Zhangheng-1 electromagnetic satellite to statistically analyze anomalies in electron and oxygen ion densities before strong earthquakes (Ms ≥ 6.0) in western China and its neighboring areas. The goal was to investigate the physical mechanisms underlying electron and oxygen ion generation by evaluating the correlations between such anomalies and the seismic activity before the 6.4-magnitude earthquake in Yangbi, Yunnan, China, on 21 May 2021. Nine (75%) of the twelve earthquakes that occurred during the study period and were not affected by magnetic storms were preceded by anomalous electron or oxygen ion densities of 1.1–4.5 × 1010/m3 and 2.8–6.0 × 1010/m3, respectively. The anomalies were generally observed within the two weeks preceding the earthquakes and were associated with most strike-slip and thrust earthquakes, which were mainly located on the southeastern and northwestern edges of the Tibetan Plateau—but not normal fault earthquakes. The anomalies were likely the result of acoustic-gravity waves generated by slow vibrations of the Earth's surface reaching the ionosphere, where they cause oscillations in ionospheric electron and ion densities. In addition, the association between ionospheric anomalies and strong earthquakes was confirmed by the observation of other atmospheric anomalies before the Yangbi earthquake. [ABSTRACT FROM AUTHOR]

Organic matter accumulation exhibits different distribution patterns in time and space and tends to be controlled by many factors. This study investigated the mechanisms that control the accumulation of organic matter in the Xianfeng area of western Hubei Province, South China through sedimentological and geochemical analyses of wellbore samples. The results showed that the total organic carbon (TOC) content, mineral content, and elemental geochemical data of the Wufeng-Longmaxi Formations varied significantly with depth. Based on the sharp changes in the vertical profiles of the TOC content, Gamma-ray, and numerous geochemical parameters, as well as regional stratigraphy, this study divided the section from the Upper Ordovician Wufeng Formation to Lower Silurian Longmaxi Formation into six units (W1, W2, GYQ, L1, L2, and L3). The TOC content was positively correlated with redox proxies (DOP T , V EF , and Mo EF) and primary productivity proxies (Cu EF and Ni EF), and negatively correlated with terrigenous input proxies (Al, K, and Ti). The correlation coefficients suggest that the primary factors affecting organic matter accumulation are redox conditions and paleoproductivity, while terrigenous input is a secondary controlling factor. This study proposed an organic matter accumulation model based on the organic matter characteristics, lithofacies, sedimentary environment, and geological setting of the study area. During the deposition of Unit W1, organic matter was well-preserved owing to the anoxic bottom water environment resulting from strong water mass restriction. During the deposition of Unit W2, the rising sea level led to the development of anoxic-euxinic bottom water conditions, and the joint influence of nutrients from upwelling in the open sea and volcanic eruptions enhanced productivity, resulting in the most intense accumulation of organic matter. Unit GYQ had low TOC content due to low productivity despite anoxic conditions. During the deposition of Unit L1, the uplift of the Hunan-Hubei Submarine High caused the depocenter to shift westward and the sea level in this area to drop, resulting in suboxic bottom water and relatively low productivity in the surface water layer. During the deposition of Unit L2, the regional sea level drop resulted in increased input and dilution of terrigenous clasts, thus leading to low TOC content. During the deposition of Unit L3, continuously enhanced terrigenous input due to climate warming and sea level drop became the major factor controlling the organic matter accumulation. In summary, the main factors controlling the organic matter accumulation differed significantly at different evolutionary stages. Compared with the Jiaoshiba area, the Xianfeng area in western Hubei experienced continuously increased terrigenous input, a less reductive water mass, a significant decrease TOC content, and a westward shift of the depocenter since the early stage of the Longmaxi Formation deposition. These changes may be related to the intense uplift of the Hunan-Hubei Submarine High triggered by the Kwangsian Orogeny. These results provide important implications for the understanding of the accumulation of organic matter in the Wufeng-Longmaxi Formations and paleogeographic changes. [ABSTRACT FROM AUTHOR]

Five large earthquakes of M ≥ 7.0 (based on the magnitude scale of the China Earthquake Networks Center) occurred in and near the Tibetan Plateau during 2008-2014, including the Wenchuan M8.0 earthquake on May 12, 2008 (BJT). In this paper, the Tibetan Plateau was chosen to be the study region, and calculating parameters of pattern informatics (PI) method with grid of 1° × 1° and forecasting time interval of 8 years were employed for the retrospective study according to the previous studies for M7 earthquake forecasting. The sliding step of forecasting interval was 1 year, and the hotspot diagrams of each forecasting interval since 2008 were obtained year by year. The relationships among the hotspots and the M ≥ 7.0 earthquakes that occurred during the forecast intervals were studied. The predictability of PI method was tested by verification of receiver-operating characteristic curve (ROC) and R score. The results show that the successive obvious hotspots occurred during the sliding forecasting intervals before four of the five earthquakes, while hotspots only occurred in one forecasted interval without successive evolution process before one of the five earthquakes, which indicates that four of the five large earthquakes could be forecasted well by PI method. Test results of the predictability of PI method by ROC and R score show that positive prospect of PI method could be expected for long-term earthquake forecast. [ABSTRACT FROM AUTHOR]

It is difficult – though important – to assess the necessary allocation of increasingly scarce water resources and yield estimation, by determining the exact amount of evapotranspiration ( ET ) and the partitioning of ET into transpiration ( T ) through the stomata of plants and evaporation ( E ) from the soil. An accurate and effective method for ET partitioning and estimation is, therefore, desirable. This paper aims to evaluate the performance of two main models for ET partitioning and estimation in terms of feasibility and accuracy: the AquaCrop (Version 4.0) model, and the SIMDualKc model. Field experiments were carried out between 2011 and 2015 in an arid region of Northwest China on two sites using full and deficit irrigation under plastic film-mulch, with the ET of maize for seed production and its partitioning components ( T and E ) being strictly measured by using the eddy covariance (EC) system or the sap flow system and micro-lysimeter cylinders. Subsequently, part of the measured data was used to calibrate the two models, so that the calibrated models could then be used to assess whether the agreement between simulation and measurement had proved successful, thus validating the models, or not. The results showed that the two models performed well with regard to their simulation of ET and T under full irrigation conditions. Under deficit irrigation conditions, the ET and T values simulated by the AquaCrop model were much closer to the actual measurement when compared with the results simulated by the SIMDualKc model. This was particularly the case when the soil was re-watered after a period of long-term water stress. For the simulated E , however, both models generated data that were distant from the actual measurements taken under full or deficit irrigation conditions using plastic film-mulch, although when the SIMDualKc model simulated E data, it came closer to the measurement than did the AquaCrop model. The comparison of two models in terms of their accuracy and feasibility based on the data analysis is discussed. [ABSTRACT FROM AUTHOR]