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The Chengdu Plain serves as the central hub for economic development in Sichuan Province. The study of its surface deformation plays a pivotal role in disaster prevention and ensuring the safety of lives and property. Based on SBAS-Interferometric Synthetic Aperture Radar technology, this paper derived the land surface deformation in the Chengdu Plain from January 2020 to October 2022, and analyzed it in relation to urban development and other natural environmental factors. Results are as follows: (1) The overall surface deformation in the study area remains stable, with a noticeable trend of westward uplift and eastward decline. Significant uplift is identified in Dujiangyan and Pengzhou, located near the Longmen Mountain, with a maximum uplift rate of +61 mm/year. Conversely, subsidence is evident from Qingbaijiang District in Chengdu to Deyang, with subsidence rates reaching a maximum of −87.8 mm/year. In the areas of Dayi and Qionglai, subsidence is relatively minor. The surface subsidence phenomenon in the study area is primarily associated with urban development. (2) The mean grey correlation coefficient between the time-series cumulative surface deformation and precipitation is 0.71, which suggests a strong relationship between the surface deformation and precipitation in the Chengdu Plain. However, a time delay is observed between the changes in surface deformation and precipitation. (3) The Longmen Mountain tectonic belt extrudes and lifts the premountain plain, playing a crucial role in shaping its topography. Additionally, the concealed fracture zone of Xinjin-Chengdu-Deyang may have contributed to surface subsidence. (4) After eliminating the effect of human factors, the cultivated land and grass land cover types exhibit a subsided state, whilst the artificial surface deformation is relatively stable, and the forest land exhibits an uplifted state. Surface deformation on different land cover types is correlated with water permeability, but it is also influenced by other factors. [ABSTRACT FROM AUTHOR]

Network-based rural development approaches, rooted in neo-endogenous or nexogenous models and aiming to mobilise the development potential of local assets and address local needs by connecting to broader external actor-networks, have been emphasised in rural development policies worldwide. Since the introduction of its National Rural Revitalisation Strategy in 2017, China has adopted more policies, and advanced more programmes, with networked features, which seek to involve local communities and non-governmental extra-local actors in the implementation of rural policy. The 'reaching in' state has a key role to play in the Chinese networked approach, which drives technocratic remedial programmes in response to rural marginalisation, and which seeks to generate new surplus value from supported local economies. This paper introduces the concept of neo-exogenous development (NED), distinguishing this emergent Chinese hybrid development paradigm from its European-Western counterparts. The 'reaching out' of communities in Europe is frequently a response to weakening state intervention, with connections made to non-state actors and networks. However, China's NED approach is characterised by a 'reaching in' active party-state and 'conducted' (or activated) communities , which are inter-connected by 'semi-formal party organisations.' To date, few research studies have explored the specific governance structure of China's NED practices and its dynamics, or sought to situate these in a broader international context of rural development paradigms. This gap in extant research impedes the transfer of knowledge on networked approaches across international rural contexts. This article reports on research investigating the implementation process of a Modern Agriculture Zone (MAZ) programme in Sichuan, a marginalised region of China. That research drew on semi-structured interviews with key actors from county and town governments, the MAZ Management Committee, local community and collective enterprises, and extra-local enterprises. It aims to unveil the distinctive local-state dynamics of NED practice, to show how the active party-state has provoked the reconfiguration of social relations and produced activated communities. • The paper introduces the concept of neo-exogenous development (NED), which is presented as an emergent rural development model. • From the imperial, to the Maoist, and to the modern period, China's rural development has been shaped by the state's desire to effectively integrate and govern an otherwise 'discrete' rural society. • Rooted in a semi-formal and clientelist rural governance tradition, NED combines exogenous 'reaching-in' state interventions with an array of steered endogenous features. • NED connects an active party-state with activated communities via semi-formal rural party networks. • Three drawbacks of NED are underscored: dependency on political recognition and impetus, reliance on public finance, elite capture of benefits. [ABSTRACT FROM AUTHOR]

The natural hydraulic connections between cascade hydropower may make hydraulic and electric connections mismatch after the market clears. Aiming at relieving the contradiction between water surplus and water shortage after market clearing, this paper proposes a new market clearing method considering the coupling relationship between water and electricity. And the method is verified by the simulation of a virtual spot market consisting of eight stations in Sichuan Province, China. The main contributions of this paper lay on three aspects: firstly, a new index called water-electricity coupling degree (WCD) and its calculation method are proposed to measure the overall situation of water shortage and water abandonment in the clearing results. Secondly, a multi-objective clearing model for cascade hydropower stations is established with the goal of minimizing power purchase cost and maximizing WCD. Thirdly, a solution method combined with the characteristics of the clearing model is developed. The case results demonstrate that the built model increases the WCD value by 1.57 % and reduces the insufficient output and surplus water by 45.18 % without increasing the power purchase cost of the power grid; The proposed solution strategy lowers the complexity of the model and improves the solution efficiency, where the search space reduction and time period merging strategies can reduce the calculation time by about 3 % and 8 % respectively. The new clearing method provides a new idea for solving the uncoupling problem of water-electricity-price in the cascade hydropower spot market. • Propose a new index called water-electricity coupling degree (WCD). • Establish a multi-objective clearing model for cascade hydropower market. • Develop a model dimensionality reduction strategy for model solution. [ABSTRACT FROM AUTHOR]

• Eleven high-quality heat flow data were added to the Sichuan Basin. • Based on the geological model, the temperature distribution of the Qixiamaokou Formation in southern Sichuan Basin was calculated. • The distribution and reserves of geothermal resources in the Qixiamaokou Formation in southern Sichuan were evaluated. The southern Sichuan Basin is an abnormal area of high present geothermal fields in the Sichuan Basin. It is a favorable area for the development of geothermal resources in the Sichuan Basin. But its evaluation of geothermal resources is lagging, which has severely affected the development of geothermal resources in the southern Sichuan Basin. In the paper, firstly, based on the temperature data of wells, the geothermal gradients and heat flows of typical wells in the study area were calculated, and the temperatures at the top and bottom of the reservoir in the Qixia-Maokou Formation were calculated using a one-dimensional steady-state heat conduction equation. Then, geothermal resource intensities and reserves of the Middle Permian Qixia-Maokou Formation in the southern Sichuan Basin were evaluated by using a method for rapidly calculating geothermal resources in sedimentary basins by multi-data fusion. Finally, suggestions for geothermal development were proposed. The results show that the geothermal gradient and heat flow values in the southern Sichuan Basin range from 15.6 to 33.70 °C/km and 49 to 85 mW/m2, respectively, and the temperature of the reservoir in the Qixia-Maokou Formation ranges from 50 to 120 °C. The geothermal resources are 3.09 × 1021 J, equivalent to 105 billion tons of standard coal, and the recoverable resources are 6.18 × 1020 J, equivalent to 21 billion tons of standard coal. The development of demonstration projects will focus on the mid- to low-temperature geothermal power generation, geothermal grain drying and geothermal agriculture in the southwestern region of the southern Sichuan Basin. The research results can provide a resource basis for the development of geothermal resources in the southern Sichuan Basin. [ABSTRACT FROM AUTHOR]

The structures of the Southwest Vortex (SWV) differ depending on the different environmental conditions, ultimately resulting in various types of disasters. Based on SWV Year Book during 20122017, this paper mainly makes statistical analysis on the characteristics of summer SWV and winter SWV. The radius and vertical depth between summer and winter SWVs are compared. Using composite method, PV tendency equation and angular momentum, the differences of both types of SWV scales are analyzed to reveal environmental conditions and the mechanism of different scales. The result shows that:(1) approximately 90% of winter SWVs are characterized by shallow pattern, but the percentage of summer SWVs sharing the similar pattern drops below 50%. Additionally, the average radius of SWVs in both seasons exhibits distinct variations with summer SWVs and winter SWVs reaching 100 km and 130 km, respectively. (2) Higher levels of environment angular momentum are exhibited in summer compared to winter, resulting in lager radius of winter SWV than summer SWV. (3) The PV tendency equation suggests that the diabatic heating effect is benefited to transport PV to higher level and strong convergence resulting in higher vertical extension height and radius contraction. (4) Winter SWV exhibits a wide range of inertial stability, which negatively affects the transport of angular momentum to the vortex core, consequently causing a maximum tangential wind and transport of angular momentum to appear outside the core. • Compared to the winter Southwest Vortex (SWV), the summer SWV is deeper on vertical scale but narrower on horizontal scale. • Winter conditions, such as lack of water vapor and more angular momentum, are more conducive to generating larger but not deeper SWV. • A mechanism contributing to the differences in summer and winter SWV scales is proposed. [ABSTRACT FROM AUTHOR]

The construction of the deep-buried tunnels of the Sichuan-Tibet railway is facing severe rockburst disasters. Pressure relief boreholes and rock bolt support are effective methods for mitigating rockburst in hard rock. However, the mechanisms and differences in control effectiveness of these methods for different types of rockburst have yet to be revealed. This paper presents the results of two true triaxial unloading rockburst tests: Static-driven rockburst (static tests) due to excavation disturbance and dynamic-triggered rockburst (dynamic tests) due to adjacent tunnel excavation. The rockburst samples include intact granite, granite with a borehole (hole-granite), and granite with a negative Poisson's ratio bolt (bolt-granite). The mitigation mechanisms of the borehole and bolt were investigated in terms of rockburst intensity, failure patterns, and acoustic emission precursors. The results show that borehole and bolt inhibit the formation of a shear fracture plane during rockburst, with the bolt's inhibition effect being more pronounced. For static tests, borehole and bolt significantly reduce rockburst intensity, with the reduction being more significant for bolt-granite. The bolt mainly inhibits the propagation and penetration of shear microcracks. In contrast, the borehole promotes the propagation of shear microcracks. However, for dynamic tests, the rockburst intensity of bolt-granite is equivalent to that of intact granite, while the borehole enhances the rockburst intensity. The bolt inhibits the final buckling crack penetration in dynamic tests, while the borehole promotes slabbing. For static and dynamic tests, the borehole has little influence on precursor indicators, while the bolt increases the difficulty of precursor capture. Generally, the pressure relief borehole is more effective in controlling static tests, while bolt-reinforced support has advantages in dynamic test control. • Rockburst mitigation mechanisms using stress relief borehole and rock bolt support were revealed. • Static and dynamic rockburst tests were conducted on intact granite, hole-granite, and bolt-granite. • Pressure relief borehole is more effective in controlling static tests. • Boreholes and NPR bolts inhibit the formation of shear fracture during rockburst. • The borehole does not influence the optimal AE precursor, but the bolt increases the difficulty of capturing it. [ABSTRACT FROM AUTHOR]

The Sichuan Basin (SCB) and its surrounding mountainous areas have complicated topography, and the "Nocturnal Rainfall in the Basin (NRB)" and "Nocturnal Rainfall in the Mountainous Areas (NRMA)" are frequent. To further clarify the relationship and the interaction between the two types of "nocturnal rainfall" synoptic systems, the characteristics of the synoptic meteorology, thermodynamics, dynamics, and water vapor fields of the nocturnal precipitation process generated by two Mesoscale Convective Systems (MCSs) that originated from the mountainous area on the western side of the SCB on June 4, 2019 were analyzed and diagnosed in this paper. In addition, the WRF-LES model was used to simulate and analyze the macro and micro physical characteristics of two precipitation centers formed by the main system MCS1 in the center of the SCB and the mountainous areas around it. The results showed as follows. (1) Two MCSs originated from the mountainous area on the western side of the SCB were generated by the eastward movement of the low-pressure trough over the Tibetan Plateau (TP) coupling the higher Convective Available Potential Energy (CAPE) value with the unstable circulation of the upper level. They matured in the SCB and matured and split in the western end of Mt. Daba, respectively. (2) After splitting, the southern part of the sub-system MCS2 sank and moved south along the southern foot of Mt. Daba and uplifted the main system MCS1. After its explosive development, two precipitation centers with the characteristics of the NRB and NRMA were formed. (3) The vertical velocity, divergence, thermal helicity, and potential vorticity could be used as the thermodynamics and dynamics diagnostic quantities to indicate the occurrence and development of the two MCSs. The potential vorticity was an obvious precursory parameter compared with the other three. The water vapor flux divergence and moisture helicity could better indicate the vertical transport of water vapor in the systems. (4) The precipitation simulation result of the WRF-LES model on the main system MCS1 in the SCB was better than that on the sub-system MCS2 in the mountainous area on the northern margin of the SCB. In each MCS1 stage, the precipitation of the NRB was mainly induced by the cold cloud process (supplemented by the warm cloud process), while the precipitation of the NRMA was mainly induced by the warm cloud process. The combination of diagnostic analysis and numerical simulation could effectively promote an understanding of the relationship and interaction between the NRB and NRMA. • The relationship and interaction between nocturnal rainfall in Basin (NRB) and mountainous areas (NRMA) by MCSs were clarified. • A diagnostic analysis method was established to analyze evolution and roles of MCSs during NRB and NRMA. • Combination of diagnosis and simulation successfully revealed the macro and micro physical mechanism of NRB and NRMA. [ABSTRACT FROM AUTHOR]

Morels (Morchella spp.) are commercially important edible mushrooms with high nutritional and medicinal value. There are more than twenty provinces in China that cultivate Morel mushrooms. As of 2023, white mold disease on cultivated Morchella sextelata has become a disease of concern in Sichuan Province, China, with a disease incidence of 12.13%. The ascocarp infected with white mold disease appears covered with a dense white mycelia of a foreign fungus and disintegrates soon after. However, the causal agent is not yet known. Therefore, this study aims to confirm both the causal pathogen by using Koch's postulates and to further establish, at the species level, the identity of this organism via morphological and molecular methods. The pathogens were later identified as Hypomyces rosellus and Hypomyces aurantius. Healthy ascocarps were inoculated with H. rosellus and H. aurantius , which produced the initial disease symptoms with white mold appearing at the inoculation sites, and H. aurantius showed stronger pathogenicity than H. rosellus ; the same pathogens were then isolated again from diseased ascocarp. To our knowledge, this is the first report of the ascocarp cobweb disease of cultivated M. sextelata caused by H. rosellus in China. Our work may be beneficial, especially for designing control measures for ascocarp cobweb disease in the commercial cultivation of M. sextelata. • In this paper, we checked the pathogenicity of Hypomyces rosellus and Hypomyces aurantius in same time. And found that Hypomyces rosellus exhibits stronger pathogenicity towards Morchella sextelata compared to Hypomyces aurantius. • We illustrated some more clearer photographs to describe the morphological characterization of Hypomyces rosellus and Hypomyces aurantius. [ABSTRACT FROM AUTHOR]

In this paper, the potential seven sets of geothermal resources in the Sichuan Basin were evaluated by using a method for rapidly calculating geothermal resources in the sedimentary basins by multi data fusion, and suggestions on geothermal development and utilization are made based on the basic characteristics of abandoned wells in the oil and gas fields. The results show that the Sichuan Basin is rich in geothermal resources. The total resources of 7 sets of thermal reservoirs reach 4.26 × 1013 GJ, of which the Qixia-Maokou Formation has the largest potential geothermal resources, reaching 1.36 × 1013 GJ. The Permian Qixia-Maokou Formation in southern Sichuan Basin has the conditions to prioritize the development of geothermal resources and has the characteristics of the highest temperature of formation water and the largest current and cumulative water production. At the same time, according to the formation temperature of abandoned oil and gas wells, they are divided into two types of wells, and different geothermal resource utilization methods are proposed. The research results can provide a model for the evaluation of geothermal resources in sedimentary basins and a resource basis for the development of geothermal resources in the Sichuan Basin. Method diagram for fast calculation of geothermal resources in the sedimentary basins by multi data fusion. [Display omitted] [ABSTRACT FROM AUTHOR]

The existing research on the multiple fluid control valves to control the balanced exploitation of natural gas in horizontal wells lacks theoretical model support. On this basis, this paper established a flow rate and pressure model of the segmented horizontal well based on the fluid control valve. The model considers the throttling performance, installation position and opening adjustment step size of the fluid control valve for the first time. Next, systematically analyzed the mechanism of mutual influence of the opening and the position on the flow rate and pressure based on multiple fluid control valves. In addition, a novel method of using the dichotomy model to adjust the production of different production segments was proposed to analyze the horizontal wells of 15 production segments in Sichuan. It was found that when the opening adjustment step size is less than 5%, the natural gas production shows irregular changes, which makes it hard to effectively control the production of each segment. When the step size is 5%, the maximum production variation is 2.7%, which will have a more significant and meaningful effect on the exploitation of natural gas. Through seven iterations, the maximum production errors of high and low production segments are 1.3 % and 1.1 % respectively, both less than 2.7%. The research results verified the correctness of the theoretical model of segmented horizontal wells based on multiple fluid control valves. This research provided a theoretical basis for the opening control of multiple fluid control valves based on different production segments of horizontal wells. • Established a flow rate and pressure model of segmented horizontal wells based on the fluid control valve. • Found the minimum adjustment opening for the numerical simulation of the balanced exploitation in horizontal wells. • Proposed a novel dichotomous method to adjust the production of different segments in the horizontal well. [ABSTRACT FROM AUTHOR]

This paper examines how perceived social equity (distributional equity, procedural equity, and recognitional equity) affects acceptance of protected areas by local communities. We also consider the consequences of these perceptions on the behaviour of local people in relation to biodiversity conservation. Despite increasing importance being given to social issues in protected area management, there is limited evidence about the effect of perceived equity on local support for conservation initiatives. Questionnaires (mostly face-to-face interviews) were undertaken with 426 households living in and around the Giant Panda National Park, which lies across the Sichuan, Shanxi and Gansu provinces of China. Structural equation modelling revealed that local residents with positive perceptions of procedural and distributional equity were more willing to support conservation and engage in conservation behaviours. Surprisingly, perceived recognitional equity had no effect on acceptance and negatively impacted conservation behaviour. This highlights that, although it is essential to promote recognitional equity, the complexities around this must be considered further. The context (e.g. age, education, village of residence) moderates the relationships between procedural equity, distributional equity and local acceptance. We suggest that, in order to achieve better park-people relationships, in addition to addressing equity concerns, it is also necessary to implement supplementary measures, such as community co-management and benefit sharing with host communities. • Procedural and distributional equity facilitate acceptance of protected areas. • Recognitional equity has an intricate relationship with local support. • Perceived justice tends to be non-linear in relation to local support. • The location of communities influences local pro-conservation behaviours. • There is a need for a better understanding of the equity-acceptance relationship. [ABSTRACT FROM AUTHOR]

The parameters of fractures, such as fracture geometries, placement, and conductivity, are critical for the production of horizontal wells in tight gas reservoirs. Current studies on fracture parameter optimization, especially those using the optimization algorithms, are often based on the assumptions that the fractures are uniformly placed with equal length and conductivity. However, non-uniform designs of fracture spacing have been proved to be effective in reducing fracture interference as well as increasing the well production, especially with strong rock heterogeneity. In addition, most of the current literature focuses on identifying optimal hydraulic fracture geometries without considering the fracture propagation process, which may oversimplify the evaluation of completion cost and result in fracture geometries that cannot be realized in practice. In this paper, an automatic optimization process, which could efficiently couple the fracture propagation, is proposed to optimize the fracture parameters. The genetic algorithm (GA) with penalty function method is used to optimize the constraint and non-linear problem. A modified PKN fracture propagation model is established to quickly predict the hydraulic fracture geometries. Fracture locations and fluid injection volume are sequentially optimized with consideration of heterogeneous rock properties. Model parameters are taken from typical tight gas horizontal wells in Jinqiu gas field in Sichuan Province, China. The results show the importance of permeability on both fracture length and production in tight gas well. The lower the permeability, the more significant the production increase after fracture location optimization. More fractures tend to be placed in area with small permeability and fewer fractures are required in highly permeable regions. With an increase in rock heterogeneity, the distribution of fractures becomes more uneven. Conversely, increasing the number of fractures can lead to a more even distribution of fractures. More fluid should be injected in low-permeability regions according to the optimization results. The optimization method is applied to a practical tight gas well in Sichuan Basin and the cumulative gas production can be increased by 6.5% to 8% when compared with the initial uniform designs. • A modified PKN model is proposed for quick prediction of fracture propagation, validated against numerical simulations. • GA is used to optimize fracture locations by considering rock heterogeneity's impact on fracture propagation and production. • Sequential optimization of fracture placement and injection volume is conducted with its reliability verified. [ABSTRACT FROM AUTHOR]

As a result of the combined influence of multi-stage and multi-directional tectonic activities, the subsurface medium in complex structural areas can easily develop intricate fault systems with varying scales and directions. Post-stack seismic and azimuth-stack attributes have limited precision in recognizing such complex fault systems. In this paper, we propose an adaptive fault enhancement workflow in offset vector tile (OVT) domain based on anisotropy theory to improve the recognition ability of seismic data for multi-directional faults and minor faults. The vertical directions of fault strikes and tectonic strikes estimated by the gradient structure tensor (GST) can be used as sensitive observation azimuths of faults. At the same time, according to the anisotropic forward modeling and real data amplitude variation with offset (AVO) analysis of minor faults in marine shale of Wufeng-Longmaxi formations in Sichuan Basin, China, the incident angles with the largest difference between isotropic and anisotropic reflection coefficients can be used as sensitive incident angles of faults. A new fault enhancement seismic data can be reconstructed from the OVT gathers by traversing the sensitive azimuths and incident angles adaptively. The 3D model and real data indicate that the faults enhanced by the workflow we proposed are clearer in shape, smaller in scale, and richer in details, which is consistent with geology and well. • We propose an adaptive fault enhancement workflow in OVT domain. • The workflow considers the azimuth and incidence contained in OVT gathers. • We discussed the recognition ability of angle stack for minor faults. • The result of shale reservoir in Sichuan Basin is consistent with geology and well. [ABSTRACT FROM AUTHOR]

This paper presents a two-stage hybrid robust programming model that integrates multiple blood products scheduling and multiple casualty types evacuation under facility disruptions risk and casualty number uncertainty. The model seeks to maximize the rescue efficiency and minimize the total operations cost. Under a set of disruption scenarios, we adopt a scenario-based robust method to address disruption risks at temporary medical centres and two robust uncertainty sets to deal with uncertain casualty numbers. We propose a proximal bundle algorithm to solve large-scale instances of the proposed hybrid robust model approximately. Extensive numerical experiments show that: (i) the trade-off between model robustness and solution robustness can help the decision-makers determine an appropriate risk-aversion weight; (ii) compared with the corresponding stochastic and scenario-based robust models, the hybrid robust model can obtain more robust solutions with a slight increase in cost; (iii) the proximal bundle algorithm can produce near-optimal solutions within reasonable computational times; (iv) some model parameters have significant impact on the total cost, which can help decision-makers set the appropriate parameters to achieve the desired outcome. Finally, we also use the real data of the 2008 Wenchuan County Earthquake in Sichuan Province, China, to illustrate the application of the model. • An HRM is developed for jointly plan blood logistics and casualty evacuation. • The model considers facility disruptions risk and casualty number uncertainty. • A PB algorithm based on Lagrangian relaxation is proposed. • Experiment results show that HRM outperforms the SM and SRM. • Real data are used to illustrate the application of the model. [ABSTRACT FROM AUTHOR]

• A spatial random forest-based downscaling and merging method (SRF-DM) is proposed. • SRF-DM performs better than the original satellite-based precipitation products. • SRF-DM is more accurate than the classical machine learning-based methods. • Spatial autocorrelation is the most important variable. • SRF-DM has a good performance even when the gauge density is low. Publicly available satellite precipitation products (SPPs) are essential inputs for hydrological models. However, the existing SPPs suffer from coarse resolutions and large uncertainties, which greatly hinder their widespread applications. Thus, to fully utilize the unique characteristics of each individual SPP, a spatial random forest (SRF)-based downscaling and merging (SRF-DM) method is proposed to fuse multiple SPPs and gauge observations in this paper. The proposed method incorporates spatial autocorrelation information between precipitation observations through a covariate. This covariate is estimated using ordinary kriging interpolation on spatial neighbors that have a high correlation with the target location. The proposed method was used to generate 1-km daily precipitation data using the datasets from five satellite precipitation products (IMERG, GSMaP, CHIRPS, MORPH, and PERSIANN) and gauge observations in the period from January 1, 2015 to December 31, 2019 over Sichuan province, China. The performance of SRF-DM was compared with the original SPPs, XGBoost-based downscaling and merging (XGB-DM), two double-layer machine learning (ML) methods, namely RF-RF and RF-artificial neural network (RF-ANN), and three single ML methods, namely RF, ANN, and RF-based Merging Procedure (RF-MEP). The experimental results demonstrate the following findings: (i) SRF-DM is more accurate than the original SPPs across different temporal scales (i.e., daily, monthly, and seasonal) in terms of statistical and categorical accuracy measures, (ii) SRF-DM outperforms the six ML-based methods in estimating high precipitation and capturing spatial precipitation patterns, (iii) the spatial autocorrelation between neighboring precipitation data is the most significant factor in both downscaling and merging, and (iv) the performance of SRF-DM is influenced by gauge density, but it still yields good results even with a limited number of gauges. On the whole, SRF-DM is considered an effective tool for generating daily precipitation products with high accuracy and resolution, which is primarily attributed to its satisfactory performance in regions with diverse precipitation patterns and topography. [ABSTRACT FROM AUTHOR]

With the completion of the poverty alleviation task in China, the Chinese economy has made great breakthroughs. Meanwhile, the implementation of Chinese "dual carbon" goal has entered an important window period of both strategic opportunities and difficulties. The emission of carbon dioxide (CO2) leads to the greenhouse effect, which affects the sustainable development of society. Therefore, this paper proposes an improved analytic hierarchy process (AHP) with Slacks-based measure integrating data envelopment analysis (SBMDEA) (AHP-SBMDEA) based efficiency evaluation model for different provincial-level administrative regions in China, which is used to analyze and optimize the Chinese energy structure of different provincial-level administrative regions. With coal, gasoline, petroleum, fuel oil, diesel, crude oil and natural gas as inputs, the per capita Gross Domestic Product (GDP) as the desired output and the CO2 as the undesired output, after linear weighted calculation of the results of the AHP-SP model and the SBMDEA model, the energy efficiency evaluation model of different provincial administrative regions in China is established. The results show that there is a large difference in efficiency between Chinese northern and southern regions, and the overall efficiency of southern regions is higher than that of northern regions. In addition, it is easier to find out the optimal energy efficiency benchmark, which can provide suggestions and help to guide the energy consumption input structure improvement of other inefficient provincial-level administrative regions. Furthermore, the energy structure can also be adjusted through the redundant variable calculated by the SBMDEA model. For example, Sichuan Province can reduce the consumption of the coal, the gasoline, the diesel, the fuel oil, the crude oil and the natural gas by 5269.95 × 10000 tons (WT), 513.01 WT, 59.05 WT, 34.37 WT, 4,73.33 WT and 130.37 billion cubic meters (BCM), respectively. Its CO2 emissions can be reduced by 1925.4 WT, and raise the efficiency of energy utilization in the province. [Display omitted] • Novel economy and CO 2 emissions evolution model based on a AHP-SBMDEA is proposed. • The proposed model can identify the optimal energy efficiency benchmark. • GDP per capita can be increased and CO 2 emissions can be decreased. [ABSTRACT FROM AUTHOR]

Hydropower resources have been developed to the cold regions in the west of China recently, wherein the dam will be subjected to high frequency of repeated freeze-thaw action during the construction process in winter, and thus will cause safety and stability problems of these projects. According to the actual construction situations of Lianghekou hydropower station located in Sichuan Province, one-side freezing and two-side thawing tests of unsaturated core-wall soil samples in a closed system are carried out, and the evolution of temperature, water and displacement as well as their interaction are tested and analyzed. The results show that with the increasing of freeze-thaw cycles, water migration results in a decrease of water content in the unfrozen zone and an increase in the frozen zone, and the water concentration area is formed in the soil column. Simultaneously, a deeper freezing depth accompanied with a shorter thawing duration after 10 freeze-thaw cycles is observed through the temperature field results, whereas a steady fluctuation of the deformation field is showed after the 7th freeze-thaw cycle. Moreover, based on the test results and exiting researches, a thermo-hydro-mechanical coupling model for unsaturated soils subjected to cyclic freeze-thaw action is proposed, in which both the permeability and compressibility are inextricably related to the void ratio, and vary in different calculated areas. Additionally, the effects of number of cycles on initial conditions and model parameters are also considered. Comparisons with the experimental data demonstrate the validity and adaptability of the proposed model in describing the freeze-thaw process of unsaturated soil. Through the combination of experiments and numerical simulation, the freeze-thaw process can be more clearly understood, and related engineering problems can be predicted with the help of the mathematical model in this paper. • One-side freezing and two-side thawing tests of unsaturated soil are carried out. • A thermo-hydro-mechanical coupling model in freeze-thaw process is proposed. • The thermo-hydro-mechanical coupling mechanism is revealed by simulations. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Pianyanzi area in western Sichuan hosts a rare sellaite-bearing orogenic gold deposit. • Gold is mostly present as visible native gold formed in two stages. • Gold precipitation was forced by interaction between auriferous fluids and wall rocks. • Metasomatized mantle lithosphere served a potential source of ore fluids. The Pianyanzi gold deposit is situated at the western margin of the Yangtze Craton, and represents a rare sellaite-bearing orogenic gold deposit. This deposit belongs to the Dauduhe gold belt of southwestern China and remains poorly documented. In this paper we present first petrographic and in-situ geochemistrical and sulfur isotope data from pyrite as well as results of multielement mapping. The deposit is dominated by native gold (average gold fineness = 980.8) filling fractures in minerals (e.g., pyrite, quartz, sellaite and hematite) or also emplaced along the contact interface between mineral grains. Pyrite is the most abundant sulfide mineral of this deposit. We identified five generations of pyrite: Py1, Py2a, Py2b, Py3, and Py4. Gold occurs in sellaite- and hematite-bearing mineral assemblages formed simultaneous with the formation of Py2a&b and Py4, respectively. Py1 formed in the Au-poor ore stage, while Py3 formed during the late galena-dominated sulfide stage. All generations of pyrite exhibit low concentrations of gold with an average value of less than 2 ppm. Py2a&b possess distinctive textures and chemical zonation, with trace elements displaying greater variations compared to Py1, Py3 and Py4. The δ34S values vary from −0.52 ‰ to 7.08 ‰, which is consistent with those of orogenic deposits of the Daduhe gold belt. The deep metasomatized mantle lithosphere acted as a potential source of ore fluids. We conclude that the co-precipitation of native gold and sellaite was triggered by the interaction between auriferous fluids and dolomite. [ABSTRACT FROM AUTHOR]