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Anthropogenic forcing caused the biodiversity loss and stability decline of communities. There is still controversy over whether the decline in biodiversity will lead to a decrease in community stability. The stability of biological communities is related to both biodiversity and structure, and this paper aims to reveal the human impacts on diatom communities' biodiversity and structure. We studied the richness, β‐diversity and network distance of diatom communities in Qinghai‐Xizang, Yunnan‐Sichuan and Lower Yangtze River Basin, China through empirical dataset and simulation method. The results showed that the diatoms richness in the Qinghai‐Xizang and the Yunnan‐Sichuan region was lower and the network distance was higher than that of the Lower Yangtze River Basin. β‐diversity in the Lower Yangtze River Basin was the lowest and the diatom network distance responds negatively to human population densities in China. The simulation showed that the network distance kept constant during random species loss, and declined while specialist species were lost or replaced by generalist species. The results suggested diatom communities' homogeneity and stability decline were associated with human activities. Human impacts may cause biodiversity loss targeted to specialist species or no biodiversity loss while generalist species replace those specialist species. This study showed that how diversity changes determined ecological stability depends on the type of species changes. [ABSTRACT FROM AUTHOR]

The security of natural gas supply and demand has always been an important topic, and as a result, analyzing and predicting the supply and demand of natural gas has received considerable attention from researchers. Numerous studies have extensively researched the supply and demand of natural gas. The main purpose of this study is to explore the supply‐demand balance mechanism for natural gas security. A system dynamics model is constructed to assess the supply and demand of natural gas in Sichuan Province, China. A new system dynamics model based on domestic gas, production gas, ecological environment and natural gas supply is proposed. The study considers four scenarios: natural development, economic priority development, environmental priority development and coordinated development. The results show that the rapid economic development has led to an excessive environmental carrying capacity, a larger gap between natural gas supply and demand, a decline in the quality of life of residents, and even affected the energy security of Sichuan Province and China. The findings also show that people's overprotection of the environment can lead to slow economic development, which prevents it from achieving its desired goals. The coordinated development scenario in this paper not only ensures the production of natural gas and the quality of life of residents, but also is an optimal scheme with low energy consumption and pollution. According to the research conclusions, considering the overall situation of China's energy security and the situation in Sichuan Province, the author proposes reforms from the supply and demand sides of natural gas. [ABSTRACT FROM AUTHOR]

The development of foreign electricity markets has been relatively complete, while China's electricity market started late and the design of the market mechanism needs to be improved, so the selection of a suitable market model and the design of the market mechanism in hydropower‐rich regions is conducive to the healthy development of the electricity market. While most of the first eight pilot regions in China have entered the long‐period continuous operation stage, and all the second batch of six power spot pilots have started the simulation trial run. However, the construction of power markets in hydropower‐rich regions of China, Sichuan, and Yunnan, still faces multiple problems to be solved, such as ensuring the reliability of medium‐ and long‐term power supply, improving the efficiency of hydropower resources utilization and consumption scale, and maintaining the stability of market prices. In this paper, the authors establish a multi‐scale joint clearing model for different market models considering both long‐term and short‐term operation strategies, and conduct simulations of different market models at different time scales to compare and analyze the optimization results and electricity price fluctuations of different market models. It can stabilize the market price and reasonably reflect the true value of hydropower, and also promote the consumption of clean energy and guarantee the reliability of power supply in the medium and long terms. Finally, suggestions are made for the selection of electricity market models, the security of energy supply and the design of sustainable development mechanisms for hydropower in hydropower‐rich regions such as Yunnan and Sichuan in China, with a view to providing useful references for the construction of China's electricity market. [ABSTRACT FROM AUTHOR]

More than 50 earthquakes occurred in the Luding region, including a 6.8‐magnitude earthquake on September 5, 2022, which induced huge amounts of geological disasters. As the main triggered factors for the geological disasters, the vegetation, precipitation and temperature show regular changes on the time axis. Thus, this paper based on the spatial–temporal evolution of the precipitation, temperature and normalized difference vegetation index (NDVI), focuses on the susceptibility of the Luding area using the weighted information content method (ICM) and analytic hierarchy process (AHP) for the post‐earthquake regional planning and reconstruction. In the Luding area, it was found that there were 18 debris flow gullies, and 470 geological disasters scattered in the debris flow gullies. The NDVI of the study area has been declining in recent years, with only about 12% of the NDVI increasing from 2015 to 2020. From 2011 to 2015, the annual cumulative precipitation has been dropping overall, while the July average temperature has increasing quadratic functions after decreasing trend. Furthermore, the studied area's geological hazards susceptibility was classified into five categories, with extremely low susceptibility accounting for 5.82%, low susceptibility accounting for 13.61%, moderate susceptibility accounting for 38.54%, high susceptibility accounting for 39.96% and extremely high susceptibility accounting for 2.08%. The geological disasters in moderate, high and extremely high susceptibility accounted for approximately 95.08%, and the covered area of geological disasters in moderate, high and extremely high susceptibility accounted for 88.06%. Through the receiver operating characteristic (ROC) curve of the model verification found the AUC = 0.743. The geological hazards susceptibility study results show that the approach is useful for the analysis and prevention of geological disasters. [ABSTRACT FROM AUTHOR]

In the search for precursors to earthquakes, correlation has been found between geochemical characteristics of soil gases and seismic activity. In this paper we present evidence that seismic waves can trigger emission of soil radon (Rn) and carbon dioxide (CO2). An active experiment was performed in two fault zones in China, the Annighe fault in Sichuan province and the Xiadian fault in Heibei province. An active seismic source was used to generate seismic waves at 10 m depth in wells within bedrock. Rn and CO2 detectors were placed around the wells at a distance of ∼1 m for observing the effects of the seismic waves on the emission of the gases. The observations confirm that the seismic waves have a significant and direct effect on the concentration and flux of soil radon and carbon dioxide. When the seismic events were triggered, the observed concentrations of Rn and CO2 immediately increased and reached peak values within 5–50 min and 30–60 min, with corresponding increases of Rn and CO2 concentrations by 10.5%–238.7% and 3.1%–54.1%, respectively. The measured concentrations and flux of CO2 and Rn after the passage of the seismic waves showed strong correlation, confirming the suggestion that CO2 is the carrier gas for Rn. To the best of our knowledge this is the first direct, in‐situ measurement of gas emission caused by the passage of seismic waves and provides important constraints for better understanding of geochemical earthquake precursors. Plain Language Summary: Observed geochemical properties of soil gases migrated from the deep Earth can be used to survey seismicity, volcanic activity and emission of greenhouse gases. However, due to difficulty in natural earthquake prediction, most observations on the geochemical effects linked to seismic activity are conducted after or away from naturally occurring events, with the effects normally inferred from seismic parameters. In this study, an active seismic source based on methane gaseous detonation was employed to artificially produce seismic events along two fault zones, and in‐situ measurements of concentrations and flux of radon (Rn) and carbon dioxide (CO2) were conducted. These observations showed strong correlation between concentrations and flux of CO2 and Rn after the events, in agreement with the hypothesis that CO2 is the carrier gas for Rn in tectonically active settings. Key Points: Soil CO2 and Rn emission triggered by a new type active source that excited at 10 m deep well in bedrock are observed at first timeQuantitative effect of seismicity on the concentration and flux of soil CO2 and Rn are presentedEmission of CO2 and Rn after the seismicity show strong correlation and proved that CO2 is the carrier gas for Rn [ABSTRACT FROM AUTHOR]

Neoproterozoic strata are widely developed in the Upper Yangtze region of South China, among which the Sinian Dengying Formation has been discovered with numerous large gas fields in the Sichuan Basin, and hence they have become an essential domain for natural gas exploration and development. The early‐to‐middle Neoproterozoic Nanhua System and Doushantuo Formation are characterized by rifting deposits in the northeastern margin of Sichuan Basin, but their depositional succession and sequence architectures are still unclear, which has largely restricted our understanding of the resource potential of these strata. In this paper, based on the outcrops of the Neoproterozoic Nanhua System and Doushantuo Formation in the northeastern margin of Sichuan Basin, we describe the stratigraphic distribution and sedimentary evolutionary characteristics, and establish the regional stratigraphic framework, sedimentary cycle and evolutionary sequence of the Nanhua System and Doushantuo Formation. The results show that the lithology of the Nanhua System and Doushantuo Formation is primarily composed of conglomerate, conglomeratic sandstone, medium‐fine sandstone, siltstone, mudstone, shale and tillite; a variety of sedimentary facies including alluvial fan, river, delta, coastal shore, shelf, basin and tillite were developed; five third‐order sequences could be identified, representing multiple cycles of marine transgression and regression. The climate during the deposition of the Nanhua System and Doushantuo Formation underwent from a warm and humid pre‐glacial period through cold and arid multiple glacial periods to a warm and humid interglacial period, which consequently formed a sedimentary sequence of alluvial fan and fluvial delta to tillite during the early period, shelf basin to tillite during the middle period and slope basin to delta facies during the late period. In terms of a plan view, the depositional pattern is composed of alluvial fans and deltas at the proximal part of the rift, deep‐water shelf to slope at the middle part of the rift and slope to basin facies at the central part of the rift. Finally, we propose that large‐scale distribution of high‐quality source rocks developed in the interglacial Datangpo and Doushantuo formations, while fluvial‐deltaic reservoirs occurred in the Gucheng, Nantuo and Doushantuo formations, thus showing favourable resource potential and exploration prospects within the Sichuan Basin. [ABSTRACT FROM AUTHOR]

Obtaining the most Stimulated Reservoir Volume (SRV) by forming a complex fracture network is the prerequisite for shale gas hydraulic fracturing. In this paper, a coupled DFN–DEM model is presented based on a realistic discrete fracture network from fracturing treatment, to simulate the complex interactions between a created hydraulic fracture and a natural fracture system in shale. The sensitivity analysis of numerical simulation was performed to investigate the effects of hydraulic fracture length, multi‐fracture spacing, and internal friction angle on the stimulation reservoir area. The simulation results revealed that regardless of the DFN distribution and the length of hydraulic fracture, shear failure always tracked on the existing natural fracture plane. The amount and depth of the natural fracture shear into formation increased as the hydraulic fracture grew in length. Moreover, the actual dynamic morphology of fracture network was the radial or dendritic. A drastic change of permeability along the distance from injection may stimulate the fracture networks especially near the wellbore. For the multi‐fracture, the opening of the second fracture was able to stabilize the sheared fractures at the tip of the initial fracture. The shear failure area around the second fracture tended to increase with the growth of the length of the second fracture. Fracture network connectivity in the system is better for the optimal fracture spacing, and then fluid penetration during injection will influence the permeability evolution during stimulation. The stimulation reservoir area of the fracture network and the natural fracture friction angle had a quadratic relationship. Finally, the results by the data from field measurement in Sichuan, China verified that the proposed coupled DFN–DEM model had an accuracy up to 91.7%. The research results provide a reference for predicting the development of fracture network far away for multistage fracturing treatment. [ABSTRACT FROM AUTHOR]

Understanding the features of the hydrocarbon generation and expulsion of the Upper Triassic Xujiahe Formation (T3x) source rocks is important to properly guide petroleum exploration in the Xujiahe Formation in the Sichuan Basin. Based on mass balance, the hydrocarbon generation and expulsion from the T3x source rocks are characterized in this paper through a method (i.e., hydrocarbon generation potential index using pyrolysis data) different from that used in previous studies. The threshold and peak of hydrocarbon expulsion are determined to be Ro = 0.9% and 1.15%, respectively. The amounts of hydrocarbon generated and expelled in the T3x source rocks are 4,525.5 × 108 and 2,420.5 × 108 t, respectively. Moreover, three hydrocarbon expulsion regions T3x have been identified in the Sichuan Basin. On the basis of the hydrocarbon generation and expulsion features of the source rocks and the distribution of the oil‐and‐gas reservoirs, the quantitative model of the hydrocarbon accumulation probability under the control of the T3x source rock is established via single‐factor regression analysis. The predictions obtained through this analysis show that the favourable oil‐and‐gas exploration areas in the Xujiahe Formation are distributed in the Qionglai, Chengdu, and Deyang regions, as well as in the west of Yilong region. Further, the results show that 78% of the discovered oil‐and‐gas reservoirs are located in the predicted favourable and relatively favourable oil‐and‐gas exploration areas. [ABSTRACT FROM AUTHOR]

The exploration of high production, natural gas wells (>106 m3/d) has been extremely successful in the Gaoshiti and Moxi areas of the Leshan–Longnvsi paleo‐uplift, in the west‐central Sichuan Basin. This paper focuses on the Sinian and Cambrian reservoirs from the Gaoshiti and Moxi areas, where a dataset of new trace elements in bitumen and potential source rock is reported and where hydrocarbon‐source correlation is attempted based on trace elements characteristics of the 12 potential source rocks and 22 bitumen samples. Results show that the bitumen from the three reservoirs can be distinguished from each other using trace element distribution patterns and redox‐ and provenance‐sensitive elemental ratios. Bitumen in the second and fourth members of the Sinian Dengying Formation were derived primarily from the third member of the source rocks of the Dengying Formation, which represents a self‐sourced paleo‐petroleum system. In contrast, bitumen in the reservoirs of the Cambrian Longwangmiao Formation is derived from the Cambrian Qiongzhusi Formation and third member of Dengying Formation. The trace element method used in this study improves our understanding of the complex hydrocarbon–source relation and confirm the potential target for petroleum exploration in the study area. [ABSTRACT FROM AUTHOR]

Risk of climate‐related impacts results from the interaction of climate‐related hazards (including hazardous events and trends) with the vulnerability and exposure of human and natural systems. Despite the commitment of the Paris Agreement, the integrate research on climate change risk combining risk‐causing factors and risk‐bearing bodies, the regional differences in climate impacts are still missing. In this paper we provide a quantitative assessment of hazards and socioeconomic risks of extreme events, risks of risk‐bearing bodies in China under global warming of 1.5 and 2.0 °C based on future climate scenarios, and quantitative evaluation theory for climate change risk. For severe heat waves, hazards might significantly intensify. Affected population under 2.0 °C warming might increase by more than 60% compared to that of 1.5 °C. Hazards of severe droughts and floods might strengthen under Representative Concentration Pathway 8.5 scenario. Economic losses might double between warming levels of 1.5 and 2.0 °C, and the population affected by severe floods might continuously increase. Under the integrate effects of multiple disasters, the regions with high population and economic risks would be concentrated in eastern China. The scope would gradually expand to the west with socioeconomic development and intensification of extreme events. High ecological risks might be concentrated in the southern regions of the Yangtze River Basin, while the ecological risk in northern China would expand. High agriculture yield risks might be distributed mainly in south of the North China Plain, the Sichuan Basin, south of the Yangtze River, and west of Northwest China, and the risk levels might continuously increase. Plain Language Summary.: Based on the climate and socioeconomic scenario data from the Inter‐Sectoral Impact Model Inter‐comparison Project and International Institute for Applied Systems Analysis, risks from climate change were identified under different warming levels, considering socioeconomic damage and ecosystem and food production losses. The relatively developed areas of eastern China exhibit high risks, and the risks show a westward and northward expansion trend. Socioeconomic damage, natural ecosystem, and food production losses would increase with socioeconomic development and intensification of global warming. We believe that a quantitative assessment of climate change risk should integrate climate‐related hazards with the vulnerability and exposure of human and natural systems. These results can provide decision‐making support for governments and a database for adapting to climate change. Key Points: Risks of socioeconomic development, ecosystem and food production would increase between 1.5 °C and 2.0 °C warming, economic losses might doubleIncreases in annual socioeconomic losses of 2.0 °C warming would be more significant than those of 1.5 °CEastern China exhibits high integrate risks of climate change, which present westward and northward trends from 1.5 °C to 2.0 °C warming [ABSTRACT FROM AUTHOR]

The southwest vortices (SWVs) are a unique type of mesoscale vortex that frequently induce torrential rainfall in China. In this study, we focused a long‐lived quasi‐stationary SWV, which was the primary system for producing an extremely heavy rainstorm within/around Sichuan (the maximum hourly precipitation was ~103.8 mm) in Mid July 2021. After reproduced the SWV's formation by using Weather Research and Forecasting model, we conducted trajectory analyses and topography sensitivity simulations to understand the effects of complicated topography on the vortex's formation. It is found that, the regions south and southwest of the SWV acted as the most important source regions for the air clusters that formed the SWV (proportion ≥ 65%), and the air clusters originated from the upper layer contributed the most (≥60%). Of these, the air clusters sourced from the upper layer southwest and south of the SWV played the most important role in the SWV's formation, as their increase in cyclonic vorticity and their contributions to trajectory number and vorticity were all much larger than those of the others. Sensitivity simulations indicated that, detailed topography features around the Sichuan Basin were crucial in determining the structure, intensity and precipitation of the SWV, whereas, the topography features were not a decisive factor for the SWV's formation. In summary, our findings are useful to enrich the current understanding of the SWVs' formation, which would be helpful to improve the related forecasts. [ABSTRACT FROM AUTHOR]

The Sichuan golden snub‐nosed monkey (Rhinopithecus roxellana) is a rare and endangered primate species endemic to China. Conducting research on the population distribution changes of the Sichuan golden snub‐nosed monkey holds paramount importance for its conservation. Our study represented a comprehensive investigation into the population distribution of the Sichuan snub‐nosed monkey by integrating data acquired from field surveys, protected areas, and historical records and using Geographic Information Systems (GIS) to explore changes in distribution across various time periods, including the historical (the Mid‐to‐Late Pleistocene), recent (1980–2000), and current (2001–2023). The research findings demonstrate a significant shift in the distribution range of the Sichuan golden snub‐nosed monkey compared to historical time frames. Notably, between 1980 and 2000, there was a sharp decline in distribution area. Analyses revealed that the southernmost distribution county for the Sichuan golden snub‐nosed monkey in Sichuan Province has shifted northward from Huili to Kangding. Furthermore, distribution changes in Sichuan Province are not solely characterized by a reduction in habitat area but also by a decrease in vertical distribution zones. Regions in the northeastern part of Sichuan with elevations below 1000 m, such as Guang'an City, Bazhong City, Dazhou City, and Nanchong City, no longer support the presence of the Sichuan golden snub‐nosed monkey. At present, the distribution range is confined to elevations between 1000 and 4000 m in the two major mountain ranges of Qionglai and Minshan. A holistic approach is required to safeguard this species. The establishment of movement corridors can play a critical role in enhancing the overall connectivity of current distribution areas. Additionally, we propose implementing a hierarchical approach to protect current habitats. Spatially differentiated conservation measures should be implemented to prioritize the protection of key habitats while simultaneously monitoring anthropogenic activities in non‐key habitats to prevent further fragmentation and isolation of the monkey's distribution areas. [ABSTRACT FROM AUTHOR]

Geochemical mapping is a crucial tool that can provide valuable insights for a wide range of applications, including mineral resources prospecting, environmental impact assessment, geological process understanding, and climate change research. Despite its significance, geochemical mapping requires spatial modeling based on sparse, heterogeneous, and potentially inaccurate data sets. Moreover, the underlying geological processes are often imperfectly understood. Therefore, uncertainty quantification (UQ) is vital in geochemical mapping to ensure accurate and reliable results, ultimately facilitating well‐informed decision‐making. In this contribution, we distinguish two primary types of uncertainties: systemic and stochastic. We identify the key sources of uncertainties in geochemical mapping and review the techniques that have been employed or hold potential for uncertainty quantification, communication, visualization, and sensitivity analysis. This contribution also illustrates the general procedure of UQ in geochemical mapping by a case study of mapping geochemical anomalies associated with gold mineralization in northwestern Sichuan Province, China. We also explore potential strategies for mitigating the critical uncertainties, such as gathering more geochemical data, developing more effective models, enhancing our understanding of the geochemical dispersion process, or leveraging other thematic information or knowledge. Future research should prioritize addressing underexplored uncertainties and implementing more practical applications to validate the UQ procedure in geochemical mapping. Plain Language Summary: Geochemical mapping is a vital tool for various applications such as finding minerals, assessing environmental impact, understanding geological processes, and researching climate change. However, the challenges lie in dealing with limited, varied, and potentially inaccurate data coupled with an imperfect understanding of geological processes. To ensure accurate and reliable results, we emphasize the importance of uncertainty quantification in geochemical mapping. Our review distinguishes between two main uncertainties, systemic and stochastic, and identifies their key sources in geochemical mapping. We also explore techniques for uncertainty quantification, communication, visualization, and sensitivity analysis. Using a case study in northwestern Sichuan Province, China, we illustrate the general procedure of uncertainty quantification by mapping geochemical anomalies related to gold mineralization. To address critical uncertainties, we suggest strategies such as gathering more data, improving models, and enhancing our understanding of geochemical dispersion. Future research should focus on exploring underexplored uncertainties and implementing more practical applications to validate the procedure of uncertainty quantification in geochemical mapping. Key Points: Geochemical mapping is intricate due to its scale‐dependent and heterogeneous natureUncertainty quantification is an essential part of geochemical mappingThe Monte‐Carlo framework is effective to account for multiple crucial sources of uncertainty manifested in geochemical mapping [ABSTRACT FROM AUTHOR]

The volatile compounds of fig (Ficus carica) are influenced by various factors. To explore the composition and difference of volatile compounds among figs, gas chromatography ion mobility spectrometry (GC‐IMS) was used to study the volatiles of figs from various regions, diverse cultivars, and after treatment with different drying methods. Aldehydes were the main volatile compounds in Bojihong from Shandong, while esters, ketones, and alcohols were the main volatile compounds in Bojihong from Sichuan and Guangdong. The volatiles of Branswick and Banane were similar, but differed significantly from those of Bojihong. Drying had the most significant effect on fig volatiles, which greatly reduced the content of benzaldehyde, (E)‐2‐hexenal, 2‐methylbutanal aldehydes, lost the content of esters such as isoamyl acetate, butyl acetate, ethyl butyrate, and generated some ketones and ethers. The results showed that Bojihong from Shandong was more suitable for the processing of subsequent fig drying products. [ABSTRACT FROM AUTHOR]

Camponotus japonicus (Hymenoptera: Formicidae) is an omnivorous social insect which builds sizable colonies in sparse woodlands or cropland and spreads across multiple climatic zones in the Chinese mainland. This study aims to reveal the role of climate changes and geological events in driving the genetic structure of social insect populations by investigating the phylogenetics and historical demography of C. japonicus in the Chinese mainland. Phylogenetic analyses were conducted based on the mitochondria DNA dataset using MrBayes and IQ‐TREE. We constructed a haplotype network, calculated analyses of molecular variance, estimated the divergence time, and reconstructed the maximum clade credibility tree. Mismatch distribution and Bayesian skyline plots were used to infer historical population fluctuations. Additionally, ecological niche modeling was employed to predict the potential distribution of the species during the present, mid‐holocene, and last glacial maximum periods in the Chinese mainland. The phylogenetic tree and median‐joining network analyses support the presence of four distinct lineages in C. japonicus. These lineages exhibit significant genetic differentiation and limited gene flow. The divergence among the four lineages began in the early Pleistocene, approximately 1.41 million years ago (Ma). Subsequently, the central lineage diverged from both the northern and southern lineages around 1.16 Ma, while the northern and southern lineages diverged from each other at approximately 1.07 Ma. Population expansion was observed in the southern, central, and northern lineages prior to the last glacial maximum, while the Yunnan‐Sichuan lineage experienced a slight increase in population size in more recent times. The predicted distribution of the species corresponds well with the actual distribution. Furthermore, the current suitable habitat areas in northern Xinjiang, southern Tibet, and the southeast coastal regions have significantly decreased compared to the last glacial maximum and the mid‐holocene periods. Our results suggest that climate oscillations and geological events play an important role in driving genetic patterns and differentiation of C. japonicus. Mountain barriers isolate populations from each other, hinder the flow of genes, and effectively prevent the spread of this species. But at the same time, it also formed refugia at low altitudes areas such as Qinling‐Bashan Mountains and Yanshan‐Taihang Mountains and provide suitable habitats during glaciation. This study provides a good model for understanding how complex climate changes and geological events affect population genetic differentiation of social insects in the Chinese mainland. [ABSTRACT FROM AUTHOR]

The increased seismic activity of the last ~10 years in Changning county of Sichuan Province comprised just small (mostly ML < 5.0) injection‐induced earthquakes. The MW 5.7 earthquake on June 17, 2019, is the largest event ever reported there. Moment tensor of the mainshock was remarkably dominated by a compensated linear vector dipole. We resolve its fine structure showing it was a doublet, allowing approximation by a thrust‐ and strike‐slip subevent. The mainshock nucleated as thrust faulting, which (together with the largest aftershocks) can be linked with previously known reverse faults, favorably oriented to regional stress field. Contrarily, the strike‐slip segment of the mainshock, less favorably oriented, was probably facilitated by elevated pore pressure due to previous injections. Shallow active strike‐slip faulting, not yet mapped in the region, is a new feature, important for future hazard assessment. Plain Language Summary: Changning county in Sichuan Basin belongs to major salt‐producing resources, with water injection wells drilled to ~3‐km depths. Enhanced occurrence of small earthquakes was observed in the last ~10 years. However, on June 17, 2019, a damaging earthquake struck the region. Seismic agencies reported diverse focal mechanisms and pointed to departures from shear faulting, typical for tectonic events. To understand these enigmatic features, we modeled records from 12 broadband seismic stations, adding over 100 first‐motion polarities. We found that the earthquake was very shallow (~4 km) and consisted of two shear events: the initial thrust faulting and the following strike‐slip faulting along an SE‐NW trending near‐vertical plane, aligned with aftershocks. The initial episode was "normal," expected on existing faults and supported by tectonic stresses of the region. Contrarily, the significant strike‐slip faulting appears to be rather "abnormal," probably facilitated by the initial shock and by elevated pressure of underground fluids. The 2019 earthquake provided a rare opportunity to illuminate interplay between long‐lasting water injections, tectonic stress, complexity of existing faults, and their dynamic interactions. That is how seismology aims at making industrial activities sustainable and safe. Key Points: This is the so‐far largest earthquake in a salt‐mining area where seismicity has been increased in previous 10 years by injection‐induced eventsMainshock nucleated as a thrust, then rupturing a previously unknown strike‐slip fault, suboptimally oriented to regional stress fieldThe complex nature of the event explains its small double‐couple component and diversity of focal mechanisms across reporting agencies [ABSTRACT FROM AUTHOR]

Climate change is a major factor affecting biodiversity and species distribution, particularly of montane species. Species may respond to climate change by shifting their range to higher elevations. The southeastern Qinghai‐Tibetan Plateau (QTP) and the Hengduan Mountains are considered as global biodiversity hotspots. However, information on the response of maple species to climate change in these regions was limited. Therefore, we selected two maple species that occur there and assessed changes in their habitat suitability under past, present and future climate scenarios in Biomod2. The results showed that temperature seasonality (bio4) was the most critical factor influencing their potential distributions. The distribution of potentially suitable habitat for Acer caesium and Acer stachyophyllum was predicted to be larger during the LGM compared to the present. Under the current climate scenario, the largest areas of potentially suitable habitat for these species were mainly located in southeastern Tibet, the Hengduan Mountains in northwestern Yunnan and western Sichuan, the Qinling‐Daba Mountains in southern Gansu and the Wumeng‐Daliang Mountains in northeastern Yunnan, western Guizhou and southeastern Sichuan. Under future climate change scenarios, the predicted loss of suitable habitat areas for these two species ranged from 13.78% to 45.71% and the increase ranged from 18.88% to 57.98%, with an overall increasing trend. The suitable habitat areas were predicted to shift towards the eastern parts of the QTP under both the pessimistic and optimistic future climate change scenarios in the 2050s and the 2070s, which became evident as global warming intensified, particularly in the eastern QTP and the Hengduan Mountains. Our results highlight the possibility that the diverse topography along altitudinal gradients in the QTP and the Hengduan Mountains may potentially mitigate the range contraction of mountain plants in response to climate warming. These findings provide a basis for planning conservation areas, planting and species conservation in the mountainous areas of southern China under the anticipated global warming. [ABSTRACT FROM AUTHOR]

On 20–22 July 2012, a severe rainstorm occurred in the Sichuan basin of Southwest China and in the Beijing area of North China. This rainstorm was related to the activities of a Tibetan Plateau vortex (TPV) and Southwest China vortex (SWCV). By using radiosonde, satellite brightness temperature, and NCEP_FNL data, we investigated the helicity characteristics nearly the vortexes and their effect on convection. Results showed that (1) strong precipitation in the Sichuan basin was mainly related to the interaction between the TPV and SWCV, while strong precipitation in the Beijing area was related to the northward movement of a cyclonic vortex caused by a split in the SWCV. (2) During the occurrence of the rainstorm, four mesoscale convection systems (MCSs) were observed. Their vertical structure showed a positive vorticity–negative divergence in the lower levels, and negative vorticity–positive divergence in the upper levels, accompanied by vertical upward movement. This was an important factor in the development and maintenance of MCSs, as well as one of the mechanisms for producing heavy precipitation. On this basis, we further discussed the effect of helicity on the MCSs in the atmospheric environment with rotational characteristics. Results showed that the increase in negative water vapour helicity and storm‐relative helicity were more likely to cause a strong development of MCSs. [ABSTRACT FROM AUTHOR]

The original description of Natrix leonardi (currently Rhabdophis leonardi) by Frank Wall in 1923, based on a specimen from the "Upper Burma Hills," lacked important morphological details that have complicated the assignment of recently collected material. Furthermore, although the holotype was never lost, its location has been misreported in one important taxonomic reference, leading to further confusion. We report the correct repository of the holotype (Natural History Museum, London), together with its current catalog number. We also describe key features of that specimen that were omitted from the original description, and provide new details on the morphology of the species, including sexual dichromatism unusual for the genus, based upon specimens from southern Sichuan, China. Rhabdophis leonardi is distinguished from its congeners by the following characters: 15 or 17 DSR at midbody and 6 supralabials; distinct annulus around the neck, broad and red in males, and narrow and orange with a black border in females; dorsal ground color light green or olive; some lateral and dorsal scales possessing black edges, the frequency of black edges gradually increasing from anterior to posterior, forming irregular and ill‐defined transverse black bands; eye with prominent green iris; black ventral spots with a red edge, most numerous at midbody but extending halfway down the length of the tail. In southwestern China, this species is frequently found at 1730–2230 m elevation. It has been documented to prey upon anuran amphibians, including toads. A recently published phylogenetic analysis showed this species to be deeply nested with the genus Rhabdophis, as a member of the R. nuchalis Group. That analysis also revealed the existence of two closely related but geographically distinct subclades in the molecular analysis, one of which may represent an unnamed taxon. [ABSTRACT FROM AUTHOR]

Debris flows commonly cause tremendous damage to buildings in mountainous areas. The identification of buildings susceptible to debris flows is vital for settlement risk management. The efficient identification method is a major issue limiting the targeted regional policy setting. By combining geographic information system (GIS) and Deep Encoding Network (DE‐Net) methods, we proposed an automatic identification method for buildings highly susceptible to debris flows with large‐scale digital elevation data and high‐resolution remote sensing imagery. The judgment criteria were based on a vulnerability matrix containing different threshold values of the horizontal distance (HD) and vertical distance (VD) between buildings and channels obtained from the statistics of 362 buildings destroyed by 23 debris flows and the maximum debris flow depths of 26 events, respectively. Five steps, which are debris flow channel extraction, building extraction, building cluster segmentation, distance calculation, and building classification, were implemented in the method. A case study in Puge County, Sichuan Province, demonstrated the high identification potential of the method for buildings susceptible to debris flows in large areas with only scarce information available. The identification results provide valuable information regarding high‐risk residential areas to governments and facilitate targeted measure design in these areas in the initial planning stage. [ABSTRACT FROM AUTHOR]

Aim: The mechanisms by which global biodiversity hotspots harbour and conserve high genetic and morphological diversity of endemic species remain unexplored. Relic species of ochotonids in the genus Ochotona are confined to alpine habitats and highly sensitive to environmental changes. We studied the genomic and ecological mechanisms underlying the divergence and adaptive evolution of the Moupin pika (O. thibetana) and its closely related species to infer its diversification, adaptive evolution and demographic history in response to historical and recent environmental changes. Location: Hengduan Mountain Region, China. Methods: We integrated morphological, genomic and ecological data to interpret the phylogeographic structure, adaptive evolution, demographic history and range shift of O. thibetana. Phylogenetic reconstruction was based on Cytochrome b (CYTB), the mitochondrial genome and single‐copy orthologues of the whole genome. Gene flow among extant lineages, as well as from extinct species, was inferred by multiple algorithms. Demographic history was inferred using the pairwise sequential Markovian coalescent and high‐resolution analysis of linkage disequilibrium. We also predicted the range shift of this species by using ecological niche modelling. Results: Phylogenetic reconstruction revealed an unusual mitochondrial lineage of O. thibetana from the western Sichuan Basin, which was named O. qionglaiensis in previous studies. Extensive gene flow was detected among genetic lineages of O. thibetana, which has distinct phenotypic variation in hair thickness and colouration, as well as notable morphological differentiation in external and craniodental measurements. Multiple members of the keratin gene family were identified as introgressed loci from some ancient species to O. thibetana. The Moupin pika underwent dramatic population shrinkage in the late Quaternary, with a clear trend of population growth in approximately the last 70 generations. The potential distribution range of O. thibetana showed a clear trend of expansion in the future. Main conclusions: The unusual mitochondrial phylogenetic pattern of O. thibetana resulted from "extended ghost introgression," a new evolutionary model proposed in the present study, and thus rejected the validity of O. qionglaiensis as an independent species. Ancient introgression of keratin genes likely underlies the prominent coat phenotypic variation among genetic lineages. Clear population growth and range expansion of the Moupin pika in recent generations probably benefitted from recent global warming and vegetation recovery, which not only contributed to the conservation of large mammals but was also beneficial to small mammals endemic to alpine habitats. [ABSTRACT FROM AUTHOR]

The Upper Triassic Xiaotangzi and Xujiahe formations are important gas exploration targets in the Sichuan Basin. This article, based on a systematic analysis of sandstone clastic framework components, depositional structures, clay minerals, trace elements and organic geochemistry, gives a detailed discussion regarding their sedimentary environment. There exist abundant tide‐generated depositional structures in this sequence, and the sedimentary provenance was dominated by a recycled orogen belt in the north and by a continental block at an early stage then recycled orogen belt at the late stage in the south of the western Sichuan Basin. The Xiaotangzi Formation and members 2–3 of the Xujiahe Formation only have authigenic illite and chlorite. In contrast, members 4–6 contain increasing kaolinite and decreasing illite and chlorite from bottom to top. The water column salinity gradually downgraded from hyperhaline, euhaline and polyhaline of the Xiaotangzi Formation to member 2 to polyhaline and mesohaline of members 3–6. The source rocks of the Xiaotangzi and Xujiahe formations have a generally low Pr/Ph, minus the value of (Pr/nC17)‐(Ph/nC18), and high values of Pr/nC17 and Ph/nC18. They also show apparent dominance of 9‐MP in methylphenanthrene composition and different point groups of fluorenes, dibenzofurans and dibenzothiophenes from marine or salt lake facies, as well as typical swamp facies. In conclusion, the Xiaotangzi Formation and members 2–3 were deposited in a marine environment, whereas members 4–6 were deposited mainly in a transitional to the continental environment. [ABSTRACT FROM AUTHOR]

Climate change affects the species spatio‐temporal distribution deeply. However, how climate affects the spatio‐temporal distribution pattern of related species on the large scale remains largely unclear. Here, we selected two closely related species in Taxus genus Taxus chinensis and Taxus mairei to explore their distribution pattern. Four environmental variables were employed to simulate the distribution patterns using the optimized Maxent model. The results showed that the highly suitable area of T. chinensis and T. mairei in current period was 1.616 × 105 km2 and 3.093 × 105 km2, respectively. The distribution area of T. chinensis was smaller than that of T. mairei in different periods. Comparison of different periods shown that the distribution area of the two species was almost in stasis from LIG to the future periods. Temperature and precipitation were the main climate factors that determined the potential distribution of the two species. The centroids of T. chinensis and T. mairei were in Sichuan and Hunan provinces in current period, respectively. In the future, the centroid migration direction of the two species would shift towards northeast. Our results revealed that the average elevation distribution of T. chinensis was higher than that of T. mairei. This study sheds new insights into the habitat preference and limiting environment factors of the two related species and provides a valuable reference for the conservation of these two threatened species. [ABSTRACT FROM AUTHOR]

As the country implements the reform of the electricity market and a large number of renewable energy resources (RES) are connected to the grid, the model and algorithm of traditional transmission network expansion planning (TNEP) are not suitable. A model of TNEP is built, in which the investment cost of new lines and the market‐based annual congestion surplus are selected as objective functions. A probabilistic DC power flow method is used to describe uncertainties of RES generation. A new algorithm, Hybrid‐Adaptive Differential Evolution with Decay Function (HyDE‐DF), is applied to solve the model of TNEP for the first time. Analysis and comparison in the IEEE 18‐bus system and the 52‐bus system in an area of Sichuan Province prove the feasibility, effectivity, and practicability of the model and solving algorithm. Some comparisons are performed using other variants of Differential Evolution (DE) and a swarm intelligence optimization algorithm to demonstrate the performance superiority of the new algorithm and new application. It is worth mentioning that in the 52‐bus system of an area of Sichuan Province, the investment cost obtained by the new algorithm is at least one or two orders of magnitude lower than other algorithms. [ABSTRACT FROM AUTHOR]

A set of nodular limestones was developed in the first member of the Middle Permian Maokou Formation (denoted as the Mao‐1 member) in the south‐eastern Sichuan Basin, south‐west China. Borehole coring has shown excellent signals of oil and gas from the Mao‐1 member carbonates, and many drilling wells have obtained industrial‐level gas flow. To assess the natural gas exploration potential of the Mao‐1 member in this area, sedimentary characteristics of drilling cores are described, and the formation mechanism of natural gas reservoir and its key controlling factors are also evaluated using data obtained from field geological survey, core observation, and laboratory experimental analysis. On this basis, the process of natural gas accumulation and evolution is examined. The results show that the Mao‐1 member nodular limestone comprises abundant marls and packstone to wackestone, and they were deposited in a lower part of the carbonate ramp setting. The marls exhibit rather high organic‐matter abundance and hydrocarbon generation capacity. Natural gas is mostly enriched in the marls developed talc diagenetic shrinkage pores and a certain number of organic‐matter pores, and their reservoir properties are much better than that of packstone‐wackestone. The natural gas in the Mao‐1 member is mainly self‐generated oil pyrolysis gas. The gas reservoir is characterized by the co‐existence of source rocks and reservoir, a lithology‐controlled reservoir, and a structure‐fracture‐controlled enrichment mechanism. Organic‐matter‐rich marl constitutes the material basis for natural gas accumulation. Talc diagenetic shrinkage pores provide storage space for natural gas. Preservation conditions are the key to natural gas accumulation, and natural fractures are beneficial to high gas production. The gas reservoir is characterized by early intraformational enrichment and late interformational adjustment. The finding of the nodular limestone gas reservoir of the Mao‐1 member provides new insights into unconventional gas exploration in the Sichuan Basin, and shows great potential for increasing natural gas reserves and production in China. [ABSTRACT FROM AUTHOR]

The middle reaches of the upstream of Jinsha River (MRUJR) is located in the eastern segment of the Jinsha River suture zone on the southwest of China. A study of the MRUJR based on tectonic geomorphology is noteworthy for providing a profound understanding of the tectonic transition between the Sichuan‐Yunnan and Qamdo blocks and active tectonics in various subbasins. Based on the global digital elevation model Shuttle Radar Topography Mission 1 (30 m resolution) data and geographic information system techniques, four geomorphic indices, the hypsometric integral, stream length‐gradient, drainage basin asymmetry, and drainage basin shape were calculated and analysed. Combined with geologic evidence from field surveys and fault slip rates estimated, the tectonic activities and mechanisms were discussed. Through the specific analytical comparisons, the variations in the geomorphic indices were unlikely affected by lithology and climate but showed changes in relevant tectonic activity. The analysis results of geomorphic index value manifested related strong activities in the northwestern and southeastern regions of MRUJR, tilt directions are mainly SW–NE and NE–SW, respectively. The MRUJR is undergoing rapid uplift. These results are consistent with the field evidence. [ABSTRACT FROM AUTHOR]

The Sichuan‐Yunnan region is located at the intersection between the South China Block, the Indian plate, and the Tibet Plateau and is crisscrossed with deep and large faults and is characterized by strong seismic activities and the extrusion of the Tibetan Plateau. Here we employ 1‐year continuous waveforms of the vertical component of 89 broadband seismic stations using noise tomography in this region to evaluate the velocity structure and its implications. Through single station data preprocessing, cross‐correlation calculation, stacking, group velocity dispersion measurement, and quality evaluation, the group velocity dispersion curves of Rayleigh waves for the different periods were extracted in this area. We then use the surface wave tomography method to obtain the Rayleigh wave group velocity distribution of 9–40s. Finally, the S‐wave velocity structure in the depth range of 0–60 km is calculated by pure path dispersion inversion. The results show that a large‐scale low‐velocity anomaly in the lower crust runs through the Sichuan‐Yunnan rhombus block (SYRB) to Yangtze Block from west to east, which might correspond to the extrusion of the Tibetan Plateau or channel flow. On the other hand, the seismic activities are mainly concentrated at the western part of the region, with the earthquakes distributed at the boundary between the low‐ and high‐velocity structures, as well as the adjacent region, which we correlate with the extrusion of the Tibet Plateau. Plain Language Summary: Based on noise tomography, we obtained the S‐wave velocity structure in the depth range of 0–60 km in the Yunnan‐Sichuan region of China. The shallow part of the crust in the Sichuan Basin is characterized by low velocity, which might be the influence of the sedimentary strata, whereas the middle and lower crust show a high velocity structure. In contrast, the SYRB and the Yangtze Block shows the low‐velocity anomaly in the lower crust, which might be associated with the eastern extrusion of the Tibetan Plateau or the channel flow. We correlate the earthquakes distributed at the boundary between the low‐ and high‐velocity structures, as well as those in the adjacent region, which may be induced by the extrusion of the Tibet Plateau. Key Points: The significant low‐velocity anomaly might be associated with the channel flow induced by the extrusion of the Tibetan PlateauThe eastward extrusion of the Tibet Plateau is obstructed by the rigid crust of the Sichuan Basin, which lead to seismic activityThe earthquakes are distributed at the boundary between the low‐ and high‐velocity structures [ABSTRACT FROM AUTHOR]

Abtract The Lower Cambrian Qiongzhusi shale and the Upper Ordovician–Lower Silurian Wufeng‐Longmaxi shale are major source rocks and important shale gas exploration targets in the Sichuan Basin. Cutting and core samples from two shale gas wells in south‐western Sichuan Basin have been selected for organic matter (OM) reflectance measurement and Raman spectra analysis with the aim to determine maturity. The results were incorporated for basin modelling to construct the thermal evolution of this area. Graptolite fragments and pyrobitumens are the dominant form of OM in Wufeng‐Longmaxi shale. A limited number of the OM as pyrobitumens and vitrinite‐like particles is presented in Qiongzhusi shale. According to the measured reflectance of OM in conjunction with the maturity calculated using Raman spectra, the equivalent vitrinite reflectance (EqVRo) values based on solid bitumen and graptolite is 2.53–2.81% for the Wufeng‐Longmaxi shale. The EqVRo value is 2.85–3.53% within 300 m depth intervals for the Qiongzhusi shale. A significant difference in oil generation occurred before the Late Permian between Qiongzhusi shale and Wufeng‐Longmaxi shale based on basin modelling and reassessment of previous published data. Compared with the Qiongzhusi shale, the Wufeng‐Longmaxi shale would have lower maturities before Late Permian and less hydrocarbon could be generated/expelled at that time, therefore, this shale remained with a large amount of oil, which could crack into gas. This difference had shown a favourable time relationship for generation and accumulation of shale gas in Wufeng‐Longmaxi shale. [ABSTRACT FROM AUTHOR]

Evaluation of natural fractures is the key issue of the prediction of sweet spots in deep tight sandstones. In this article, taking the tight gas sandstone reservoir of the Xu 2 Member (second member of the Upper Triassic Xujiahe Formation) in Xinchang Gas Field, West Sichuan Depression as an example, we systematically studied the characteristics, formation periods, influencing factors, and developmental mode of fractures using testing results of cores, thin sections, rock mechanics, isotopes, fluid inclusions, and the structural curvature simulation method. The results show that the Xu 2 Member mainly develops vertical and high‐angle fractures. The fractures are highly effective and mainly developed in medium‐fine‐grained sandstone. The secondary minerals in the fractures have multi‐stage filling processes. The fluid inclusions are mainly gas–liquid two‐phase brine inclusions (secondary inclusions), and with the same crystal, the temperature difference between the brine inclusion and the organic inclusion is 23.7°C. Carbon and oxygen stable isotope tests show that calcite has two mixing stages. In the end, the formation periods of the fractures in the Xu 2 Member were divided into five stages. The influencing factors of fractures in the Xu 2 Member include lithology, fault, layer thickness, and structural deformation. According to geomechanical analysis, we finally established the development mode of reverse fault‐associated fractures in the Xu 2 Member. [ABSTRACT FROM AUTHOR]

There is a close relationship between the gut microbiome and health in humans including regulation of immunity and energy metabolism. This study investigated differences in the gut microbiome of herdsmen from two regions: Hongyuan pasture in Sichuan and Xilingol pasture in Inner Mongolia. We found significant differences in the gut microbiome between the two groups. The main discriminatory species between the two groups were Bifidobacterium longum, Bifidobacterium breve, Phascolarctobacterium succinatutens, Prevotella stercorea, Prevotella copri, Eubacterium biforme, and Fusobacterium prausnitzii. The abundances of Bifidobacterium longum and Bifidobacterium breve were significantly lower in the gut microbiomes of Hongyuan herdsmen than in the gut microbiomes of Xilingol herdsmen. Functional metagenomic analysis showed that more genes were enriched in glycoside hydrolase and transposase in the gut microbiome of Hongyuan herdsmen compared with Xilingol herdsmen, suggesting a higher energy demand in the gut microbiome of Hongyuan herdsmen. Significantly more genes associated with glycolysis, starch degradation, and sucrose degradation were also found in the gut microbiome of Hong yuan herdsmen compared with Xilingol herdsmen. These results indicate that herdsmen from different pastoral regions had distinct gut microbiome composition and functions. [ABSTRACT FROM AUTHOR]

Nighttime ozone (O3) reserved over the stable boundary layer (SBL) could contribute significantly to surface O3 levels. While many studies have revealed that daytime convective eddies and turbulence induced by nighttime low‐level jets can mix O3‐rich air over the SBL down to the surface, increasing nocturnal surface O3 within the cloud topped boundary layer has rarely been examined. In this study, we used measurements and a single‐column photochemistry model to investigate O3 variations within the nighttime cloud topped boundary layer over the Sichuan Basin, which is the cloudiest region in southwest China. The Santa Barbara Distort Atmospheric Radiative Transfer radiation model was coupled into the single‐column photochemistry model to investigate the nighttime radiative effects of clouds. The results showed that the nocturnal cloud top radiative cooling generated turbulence and enhanced vertical mixing below the cloud top layer. The cloud‐driven turbulent eddies even penetrated through the SBL to the surface. Consequently, it weakened the decoupling of the SBL from the residual layer. O3‐rich air over the SBL was entrained downwards to the surface, decreasing O3 aloft and increasing surface O3 at nighttime. The cloud top radiative cooling rates were enhanced with the increase in the cloud liquid water path. Higher cooling rates produced stronger turbulent transport of O3, leading to higher nocturnal surface O3 levels. The turbulent transport of O3 induced by cloud top radiative cooling is revealed as an important mechanism of vertical transport of O3 within a cloud topped boundary layer, contributing to the maximum nocturnal surface O3, which has great implications for understanding atmospheric O3 variation. Key Points: A mechanism of vertical transport of O3 within a cloud topped boundary layer is revealed using measurements and simulations.The contribution from vertical transport to surface O3 increases with cloud liquid water path, with maximum surface O3 enhancing by 30 ppb at nighttime. [ABSTRACT FROM AUTHOR]

An error decomposition method is used to analyze and track seasonal error sources of the Integrated Multi‐satellitE Retrievals for the Global Precipitation Measurement (IMERG) Version 05 daily precipitation estimations, including Early‐, Late‐, and Final‐run products (IMERG‐DE, IMERG‐DL, and IMERG‐DF, respectively) over the Sichuan Basin of China from January 2016 to December 2018. The method decomposes the total errors into hit bias, missed precipitation, and false precipitation, which can be attributed to the satellite retrieval processes. Results show that in spring, all the estimations had serious overestimation in the northwest of the basin. The major error source is the hit bias of the intensity over 25 mm/day. In summer, the three IMERG estimations overestimated the precipitation in almost the entire Sichuan Basin, especially in the south and southwest. The principal determinants of the error sources are missed and false light precipitation (<25 mm/day), while hit bias and false precipitation are the leading error sources for the moderate precipitation (25–54 mm/day). In autumn, the IMERG‐DF's overestimation mainly comes from hit and false moderate precipitation (15–64 mm/day), while the underestimation of the IMERG‐DE and DL is mainly determined by missed and false precipitation of the precipitation less than 15 mm/day. In winter, the main contributors to the underestimation of the IMERG‐DE and DL estimations are missed and false lighter precipitation (<8 mm/day). However, the total errors of the IMERG‐DF are resulting from the three components canceling one another. Additionally, missed precipitation often takes place in the autumn and winter and false precipitation in summer and winter. The IMERG‐DL shows better error control of positive hit bias and false precipitation than do the other estimations in summer. Key Points: The major error sources of the substantial precipitation overestimation in the northwest of the basin are false and hit precipitationThe calibration of GPCC monthly observation intensifies the overestimation of hit and false precipitationThe leading estimation error sources of summer moderate precipitation are missed and hit precipitation [ABSTRACT FROM AUTHOR]

Biotite is an important silicate mineral that can be used to decipher the physicochemical attributes of magmatic or hydrothermal systems. The Lizhuang rare‐earth element (REE) deposit in Sichuan Province, Southwestern China, formed from continuous magmatic‐hydrothermal processes is related to a Cenozoic carbonatite–syenite complex. Biotites are abundant in this deposit, which can be divided into two generations: generation I in intergrown with alkaline feldspar and aegirine‐augite and generation II in association with bastnäsite‐(Ce). We investigated chemical composition of the two biotite generations using electron‐microprobe(EMPA) and laser ablation–inductively coupled plasma–mass spectrometer (LA–ICP–MS) analyses to understand the development of REE mineralization. Generation I biotite has relatively high Al2O3 (10.2–12.4 wt%), TiO2 (0.49–1.85 wt%), and FeOtot (12.2–15.9 wt%), but low SiO2 (40.0–42.5 wt%) contents compared to generation II counterpart. These two generations of biotite also differ in some key trace elements. Specifically, generation I biotite has much higher concentrations of Sr (up to 234 ppm) and Ba (up to 20,796 ppm), but lower levels of Li (47.5–126 ppm) with respect to its generation II counterpart. When comparing Lizhuang biotites with those of other barren carbonatite complexes, we identified an unusual compositional trend in the generation II biotites termed as fluorphlogopite trend. This trend is marked by the continuous increase in the Mg content towards mineralization and, therefore, can serve as a diagnostic attribute in the determination of mineralized carbonatite complexes. Fluorine in biotite is an important parameter that can be used as a vector for REE exploration, because the generation II biotite presents much higher fluorine contents (2.20–4.06 wt%) than its generation I counterpart (0.87–1.59 wt%). The compositional data of the two biotite generations indicate a depletion of Fe and a progressive enrichment in Mg and F in the ore‐forming system during its evolutionary process. Physicochemical parameters estimated by biotite composition suggest that there is a trend of strongly decreasing temperature from the crystallization of generation I to generation II biotite. It is therefore concluded that temperature is a major factor favourable for REE mineralization in the Lizhuang deposit, particularly given related experimental studies. Taken together, we propose that biotite composition could serve as a proxy for REE mineralization processes and as a reliable index for REE routine exploration in a carbonatite‐related setting. [ABSTRACT FROM AUTHOR]

For more than three decades, the depleted Rongchang gas reservoir in China's Sichuan Basin was used for the disposal of unwanted water, which resulted in induced earthquakes, with magnitudes as high as 5.2. After all wells were closed, the frequency of seismic activity was observed to decay following a modified Omori law, and since April 2015, seismic activity again began to increase, and a M4.9 earthquake occurred on 27 December. The results of an epidemic‐type aftershock sequence (ETAS) model analysis show that forced seismicity accounted for more than 70% of the total events. For most M ≥ 3.5 earthquakes, including two M ≥ 4 events, the estimated overpressure was lower than the maximum injection pressure. These results, coupled with the fact that postinjection seismic activity has similar characteristics to seismicity during injection, indicate that the injected overpressure fluid was still the driving factor for postinjection seismic activity. Plain Language Summary: Prior to 2013, unwanted water was intermittently pumped into the depleted Rongchang gas reservoir at a depth of 3 km for approximately three decades, inducing many earthquakes with a magnitude up to 5.2. Although all nearby injection wells were closed in 2013, the seismicity in the area has remained relatively high. At this location, M4.9 and M4.0 earthquakes occurred in December 2016. In order to assess the situation, we carried out an integrated study focused on the area's seismicity before and after the injections ceased. The results, including the overpressure required for major earthquakes and various statistical features, suggest that the postinjection seismicity, which was the same as that during injection, was caused by the delayed rupture of preexisting faults within the reservoir and its surrounding faults. Therefore, at an injection site, at which significant injection‐induced earthquakes occurred during injections, there is still a high probability of continuous occurrence of relatively large earthquakes after injection ends. Key Points: Long‐term injection for wastewater disposal into the depleted Rongchang gas reservoir induced earthquakes with magnitudes as large as 5.2After shutting down of injection, seismicity decayed following a modified Omori law with some major eventsPostinjection seismicity demonstrates features similar to that during injection except for a change in event rate [ABSTRACT FROM AUTHOR]

Analysis of apatite fission‐track and vitrinite reflectance combined with 1‐D basin modelling was used to reconstruct the thermo‐tectonic history of the northeast Sichuan Basin, China. The study indicates that the basin has evolved through multi‐phase tectonic regimes involving a series of subsidence and tectonic uplift phases exerting significant control on the thermal history. Heating and cooling processes were largely related to deep burial and intense exhumation, respectively. Exhumation that extended from 122 to 2.5 Ma has resulted in at least 4 km of sedimentary removal. The rate of exhumation and removal (denudation) was found to have reached 58 and 35 m/Myr, respectively. The results show that the denudation magnitude is significantly higher in the eastern part reaching 5.5 km, compared with 2.2 km in the western part of the study area. The fission‐track ages demonstrate the occurrence of three cooling phases: initial‐gradually increasing (~120–70 Ma), stagnant (70–15 Ma), and rapid (15 Ma to present). This suggests that cooling was associated with different compressive thermo‐structural events that began in the mid‐Lower Cretaceous (~122 Ma) marking the subsidence climax period. With the sedimentary section approximating 8‐km thickness by the time of maximum burial, the modelled average maximum temperature and vitrinite reflectivity coefficient reached roughly 232°C, and 3.5% for the Lower Triassic Feixianguan Formation (T1f1), thus indicating the conditions of dry gas generation. The Meso‐Cenozoic thermo‐structural evolution that postdated the onset of hydrocarbon generation has been critical for the evolution of the petroleum play, including the Feixianguan Formation in the marine carbonates of the Early Triassic and the Xujiahe Formation in the non‐marine sandstones of the Upper Triassic. This resulted in the modification of primary hydrocarbon accumulations, mostly in the lower petroleum play, and development of secondary accumulation in the newly formed structural traps in the upper petroleum play. Therefore, accurate thermo‐tectonic history reconstruction is valuable for understanding the geological history and hydrocarbon prospectivity. [ABSTRACT FROM AUTHOR]

In the Cu‐Au‐Pb‐Zn‐Ag polymetallic mineralization belt of the conjuncture of Sichuan, Yunnan, and Guizhou, occurs the Taiping Pb‐Zn deposit in Proterozoic metamorphic rock strata accompanied by late Proterozoic volcanic rocks. Previous studies on this type of Pb‐Zn deposits are limited. The main purpose of this work is to investigate its metallogenic characteristic and genesis. Rb‐Sr dating of sphalerite yields 714 ± 11 Ma for the Taiping Pb‐Zn deposit, which is a new mineralization age of Pb‐Zn deposits in the Sichuan–Yunnan–Guizhou Pb‐Zn metallogenic belt, reflecting that the Pb‐Zn deposits in the Proterozoic basement strata formed in the Neoproterozoic. In addition, the characteristics of its minerals, including pyrite, sphalerite, chalcopyrite, gersdorffite, and galena, imply that the deposit formed in moderately low temperature and moderately shallow‐seated environments. Sulphur (δ34S of 10.4–12.3‰) was dominantly derived from the reduction of marine sulphate in the strata. Lead isotope data showed normal Pb characteristic, indicating that Pb came from the basement strata and it was affected by metamorphism. 87Sr/86Sr values of trachyandesite are 0.77–0.87, reflecting that Sr was derived from crustal sources. For sphalerite, (87Sr/86Sr)i (t = 714 Ma) = 0.72064–0.72135, indicating that metallogenic materials (metal) came mainly from the basement strata. The enrichment of Zn was associated with ankerite alteration. Ore‐forming fluid is characterized by moderately low temperature (112.6–188.7°C), moderate salinity (10.61–19.68% NaCl), and moderately low pressure. Compositions of H and O isotopes show that the ore‐forming fluid was derived mainly from formation water, and that tensile spaces in the carbonate rocks likely provided conduits for fluid transport and space for metal precipitation, forming layered zinc ore bodies. In conclusion, the Chengjiang period in this study area was an important stage for zinc mineralization, and the Taiping Pb‐Zn deposit is a MVT type deposit in the Proterozoic basement. [ABSTRACT FROM AUTHOR]

The variations of soil structure and soil physical–chemical properties in the process of alpine grassland desertification were revealed, and the indicators of grassland desertification were put forward in order to deepen the understanding of the law of degradation succession and development of alpine grassland. It was used to provide scientific basis for ecological restoration and improvement of ecological service function of alpine grassland. With severe desertification alpine grassland as the core in the Hongyuan County, Tibetan Qiang Autonomous Prefecture of Ngawa, Sichuan Province, China, along both the directions of wetland and arid grassland, the heterogeneity of soil structure and soil fertility in both directions was studied by the analysis of the mean weight diameter (MWD), geometric mean diameter (GMD), >0.25 mm aggregate content (R0.25), fractal dimension (D), soil bulk density, soil moisture content, and soil nutrients. Our results showed that MWD, GMD, and R0.25 all gradually increased, but the D decreased with the reduction in the degree of desertification in the arid grassland and wetland, resulting in the strong stability of soil structure. The decreasing rate of the D in the direction of arid grassland was faster than that of wetland. Therefore, soil structure stability and erosion resistance in the direction of arid grassland were stronger than that of wetland soil; the D had different response to aggregates with different particle sizes. The aggregate less than 0.25 mm (r = 0.981, P < 0.01) and 1–2 mm (r = −0.79, P < 0.01) had the largest responses in the direction of the arid grassland and wetland, respectively; the aggregate more than 1 mm and 1–2 mm can be used as indicators to evaluate desertification of the soil in the direction of the arid grassland and wetland, respectively. The higher the content of the indicating aggregates, the weaker the degree of the desertification. [ABSTRACT FROM AUTHOR]

During the Late Ordovician, abundant siliceous rocks interlayered with K‐bentonites were widely distributed in the Wufeng Formation in the north‐western part of the Sichuan Basin, South China. In order to analyse the material provenance, redox condition, sedimentary environment, and their formation, here we present mineralogical and geochemical investigations on siliceous rocks samples collected from three sections. The presence of massive radiolarian tests, high Si/Si + Al + Fe + Ca ratios (0.87–0.99) and Al–Fe–Mn diagram plotting at nonhydrothermal area, reflects that the deposition of the siliceous rocks was simultaneous, effected by biogenic and terrigenous origin. The TiO2–Zr, La/Th–Hf, and La/Yb‐∑REE bivariate diagrams indicate that the provenance of Late Ordovician siliceous rocks was primarily from felsic igneous rocks. According to the palaeoredox indicators (V/(V + Ni), V/Cr, V/Sc, U/Th, and Ni/Co) and the size of framboidal pyrite, it is considered that the water column conditions of the Late Ordovician siliceous rocks were likely to be anoxic in all three sections. The application of parameters for relatively immobile elements allowed us to establish a continental margin for most samples from the three sections. Finally, we propose that the deposition of siliceous rocks was related to the accretion of the Cathaysia Block to the Yangtze Block. During the Late Ordovician, huge amounts of volcanic ash were released by intensified volcanic eruptions and fell into the ocean, triggering the proliferation of radiolarians. The abundant radiolarians and the persistent continental detritus constituted the major components of siliceous rocks in the Upper Yangtze Block. [ABSTRACT FROM AUTHOR]

Sichuan taimen (Hucho bleekeri) is critically endangered fish listed in The Red List of Threatened Species compiled by the International Union for Conservation of Nature (IUCN). Specific locus amplified fragment sequencing (SLAF‐seq)‐based genotyping was performed for Sichuan taimen with 43 yearling individuals from three locations in Taibai River (a tributary of Yangtze River) that has been sequestered from its access to the ocean for more than 30 years since late 1980s. Applying the inbreeding level and genetic relatedness estimation using 15,396 genome‐wide SNP markers, we found that the inbreeding level of this whole isolated population was at a low level (2.6 × 10−3 ± 0.079), and the means of coancestry coefficients within and between the three sampling locations were all very low (close to 0), too. Genomic differentiation was negatively correlated with the geographical distances between the sampling locations (p <.001), and the 43 individuals could be considered as genetically independent two groups. The low levels of genomic inbreeding and relatedness indicated a relatively large number of sexually mature individuals were involved in reproduction in Taibai River. This study suggested a genomic‐relatedness‐guided breeding and conservation strategy for wild fish species without pedigree information records. [ABSTRACT FROM AUTHOR]

Understanding the relative importance of the factors driving the patterns of biodiversity is a key research topic in community ecology and biogeography. However, the main drivers of plant species diversity in montane forests are still not clear. In addition, most existing studies make no distinction between direct and indirect effects of environmental factors and spatial constraints on plant biodiversity. Using data from 107 montane forest plots in Sichuan Giant Panda habitat, China, we quantified the direct and indirect effects of abiotic environmental factors, spatial constraints, and plant functional traits on plant community diversity. Our results showed significant correlations between abiotic environmental factors and trees (r =.10, p value =.001), shrubs (r =.19, p value =.001), or overall plant diversity (r =.18, p value =.001) in montane forests. Spatial constraints also showed significant correlations with trees and shrubs. However, no significant correlations were found between functional traits and plant community diversity. Moreover, the diversity (richness and abundance) of shrubs, trees, and plant communities was directly affected by precipitation, latitude, and altitude. Mean annual temperature (MAT) had no direct effect on the richness of tree and plant communities. Further, MAT and precipitation indirectly affected plant communities via the tree canopy. The results revealed a stronger direct effect on montane plant diversity than indirect effect, suggesting that single‐species models may be adequate for forecasting the impacts of climate factors in these communities. The shifting of tree canopy coverage might be a potential indicator for trends of plant diversity under climate change. [ABSTRACT FROM AUTHOR]

Aim: China's Grain for Green Program (GFGP) is the largest reforestation programme in the world and has been operating since 1999. The GFGP has promoted the establishment of tree plantations over the restoration of diverse native forests. In a previous study, we showed that native forests support a higher species richness and abundance of birds and bees than do GFGP plantations and that mixed‐species GFGP plantations support a higher level of bird (but not bee) diversity than do any individual GFGP monocultures (although still below that of native forests). Here, we use metabarcoding of arthropod diversity to test the generality of these results. Location: Sichuan, China. Methods: We sampled arthropod communities using pan traps in the land cover types concerned under the GFGP. These land use types include croplands (the land cover being reforested under the GFGP), native forests (the reference ecosystem as the benchmark for the GFGP's biodiversity effects) and the dominant GFGP reforestation outcomes: monoculture and mixed‐species plantations. We used COI‐amplicon sequencing ("metabarcoding") of the arthropod samples to quantify and assess the arthropod community profiles associated with each land cover type. Results: Native forests support the highest overall levels of arthropod species diversity, followed by mixed‐species plantations, followed by bamboo and other monocultures. Also, the arthropod community in native forests shares more species with mixed‐species plantations than it does with any of the monocultures. Together, these results broadly corroborate our previous conclusions on birds and bees but show a higher arthropod biodiversity value of mixed‐species plantations than previously indicated by bees alone. Main conclusion: In our previous study, we recommended that GFGP should prioritize the conservation and restoration of native forests. Also, where plantations are to be used, we recommended that the GFGP should promote mixed‐species arrangements over monocultures. Both these recommendations should result in more effective protection of terrestrial biodiversity, which is an important objective of China's land‐sustainability spending. The results of this study strengthen these recommendations because our policy prescriptions are now also based on a dataset that includes over 500 species‐resolution taxa, ranging across the Arthropoda. [ABSTRACT FROM AUTHOR]

There have been few high‐resolution investigations covering the last glacial and Holocene from Sichuan, Yunnan, or south Asia area in the south‐west monsoon domain region. High‐resolution analyses of lake sediments retrieved from Qionghai Lake, Sichuan Province, were conducted using a combination of variables including total organic carbon (TOC) and total nitrogen (TN) concentration, low frequency magnetic susceptibility (χLF), particle size, carbonate content, and δ13C value of organic matter (δ13Corg), to provide a new perspective on the detailed paleoclimate history of south‐west China spanning the past 30 cal ka BP. Our findings suggest that organic matter in the Qionghai Lake was mainly derived from microorganisms, aquatic macrophytes, and terrestrial C3 plants. From 29.1 to 23.2 cal ka BP, low carbonate contents, high median grain size (Md values), and χLF values indicated a warm and wet climate. During the period 23.2 to 15.4 cal ka BP, low χLF, Md values, and high carbonate contents suggested a decrease in temperature and humidity. The cold and dry Last Glacial Maximum (LGM) and Heinrich 1 event (H1) were captured between 21.6 and 19.4 cal ka BP and 17.6 and 15.8 cal ka BP, respectively. During the interval 15.4 to 9.7 cal ka BP, low level of χLF values and Md values, together with relatively high carbonates, demonstrated that a dry climate prevailed in this period. Since 9.7 cal ka BP, the climate was warm and humid in the early to mid‐Holocene and shifted towards cold and dry condition in the late Holocene. A cold and dry period at 8.5 to 8.1 cal ka BP and warm and wet interval at 6.6 to 4.6 cal ka BP were identified, corresponding to the 8.2‐ka cold event and Holocene climatic optimum (HCO), respectively. These climate changes may reflect variations of the intensity of the south‐west summer monsoon, primarily in response to the Northern Hemisphere solar insolation on a millennial scale induced by orbital forcing. The position of the Intertropical Convergence Zone (ITCZ) may add a complementary effect on the evolution of the monsoon strength in the Holocene. [ABSTRACT FROM AUTHOR]

Human–wildlife conflict (HWC) has become a conservation focus for both protected area management and local communities in many parts of the world. The incidence and mediation of HWCs are rooted in coupled environmental and socioeconomic contexts. A systematic analysis of HWCs was undertaken in 2016 in the Wolong Nature Reserve located in Sichuan Province, southwestern China. Semi‐structured interviews were conducted with 201 local households to understand the occurrence of wildlife damage, the wildlife species involved, the typical losses incurred, and the mitigation measures employed. The results revealed that local HWC has increased rapidly in recent years due to effective biodiversity conservation and ecological restoration policies. Despite the widespread occurrence of HWCs, with nearly all respondents stating that they had suffered a financial loss, appropriate compensation schemes are lacking. Local respondents' expected compensation amount and style were investigated, and it was concluded that integrated compensation and community development plans are needed to mediate and resolve HWC. In particular, greater attention should be given to reduce local households' dependence on agriculture and transform local livelihood strategies to alternative economic activities not related to farming, such as ecotourism development and migrating employment. [ABSTRACT FROM AUTHOR]

A major breakthrough in shale gas exploration and development has been made concerning the black shale of the Upper Ordovician and Lower Silurian. In recent years, significant progresses have been made regarding the exploration and development of shale gas in the black shale of the Upper Ordovician and Lower Silurian. Accordingly, we investigated the petrological and geochemical characteristics of the black shale from WF2‐LM5 graptolite biozones and performed a source analysis of quartz as well as evaluated its effect on shale gas reservoirs. The black shale mainly contains clay, carbonate, and quartz with the average TOC of 2.21%. Three quartz types, Q1, Q2, and Q3, were identified via petrological and cathodoluminescence (CL) analysis. Q1 of detrital origin as suggested by its typical morphology with monocrystal structure, large grain‐size, subrounded to angular outlines, and clear edges. This is further supported by the occurrence of medium luminescence under cathodoluminescence and medium intensity of P1 and P2 and high intensity P3 according to CL images. Q2 accounts for more than 90% of quartz and exhibits cryptocrystalline texture, an irregular shape, blurring edges, and low luminescence, and its CL images show low intensity P1, low intensity P2, and high intensity P3. Q3 have the morphologies of siliceous organisms, for example, sponge spicules, radiolaria, and foraminifera. Q2 and Q3 belong to authigenic quartz derived from siliceous organisms. Th/U and V/Cr indicate black shale from LM1–3 mainly deposited in the dysoxic‐anoxic environment while black shale from LM4–5 deposited in the oxic environment. Authigenic quartz‐rich shales from LM1–3 were speculated to be the best shale gas reservoirs characterized by high TOC content, high gas content, and with negligible amount of detrital quartz. Compared with shale from LM1–3, black shale from LM4–5 usually have relatively high detrital quartz content and low TOC content and gas content. Considering the abundant interparticle pore space, the detrital quartz‐rich shale interbedded within the black shale from LM4–5, could also become good shale gas reservoirs if sufficient gas supply is guaranteed. [ABSTRACT FROM AUTHOR]

The second member of the Middle Jurassic Shaximiao Formation in the rejuvenated Western Sichuan Foreland Basin contains tens of metres of thick incised valley successions. Incised valleys have been widely discussed in traditional models; however, quantitative and detailed analyses of geometric variations and their interpreted controls on ancient incised valleys have rarely been attempted in the past. Using an integrated dataset of seismic profiles, well logs and cores, this study quantifies the geometric parameters of incised valleys and investigates the smaller-scale depositional patterns. (1) During this period, incised valleys (IV) were 5-17 km wide, 20-60 m deep and traceable for 120 km along their axis, placing these valleys among the longest seismically imaged incised valleys in the world. (2) Three nested incised valley successions IV-1, IV-2 and IV-3 can be identified. Except for IV-2, the incised valleys decrease in width and depth downstream. (3) In the downstream segment, the role of tectonism diminishes gradually, and periodic base-level changes control the form and evolution of the incised valleys. A downstream decrease in the stream power appears to be responsible for the decreasing trend in the incised valley geometry. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The upper Daguanshan Formation (middle Expansograptus hirundo graptolite biozone, Dapingian, early Middle Ordovician) of the Shuanghe area, Changning County, southern Sichuan Province, contains three new genera and species of strophomenoids: Ochyromena plana, Shuangheella elongata, and Primotimena globula, which are attributed to the Strophomenidae, Rafinesquinidae and Glyptomenidae respectively. These are the earliest known strophomenoids from the South China palaeoplate, and also the oldest rafinesquinid and glyptomenid brachiopods worldwide. Global review of the superfamily Strophomenoidea of Middle Ordovician age suggests that the first diversity peak at the species level occurred in late Darriwilian (Llanvirn) time, mainly as a result of the rapid diversification of the family Strophomenidae. The first appearance datum (FAD) of strophomenoids and their possible westward dispersal were from North China (latest Floian) and/or South China (early Dapingian), through the Chu-Ili terrane of Kazakhstan, Iran, and Baltica (early Darriwilian), to Avalonia and Laurentia (late Darriwilian). This points to the existence of early diversification hotspots of the strophomenoid superfamily in the North and South China palaeoplates during the early Middle Ordovician in generally shallow water (corresponding to BA2) environments. The high degree of similarity in the external morphology and ventral interior of the three new genera indicates that the early diversification of strophomenoids began with differentiation of the cardinalia, especially in the configuration of the bilobed cardinal process, a key evolutionary novelty for the strophomenoids. [ABSTRACT FROM AUTHOR]

The purpose of the study was to examine what science views were accepted or rejected by the Chinese university students. We administered the Thinking about Science Survey Instrument (TSSI) to 75 Chinese students in the Sichuan province who were enrolled in Science and Technology English classes. The TSSI focuses on nine key areas of science and aims at identifying whether an individual agrees or disagrees with a model science view. Chi-square tests were applied to the data. Three idealized science views were found to be accepted regarding Science and the Economy, Science for All, and Science and Public Health. The same three science views were also found to be accepted in prior U.S. studies. Directions for further research are discussed including the examining views held by diverse populations and the potential development of a global view of science. [ABSTRACT FROM AUTHOR]

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This study investigates the formation of a type of mesoscale vortex around the Sichuan Basin (i.e., the southwest vortex [SWV]) that usually induces heavy precipitation, based on a semi‐idealized simulation of eight similar SWV‐formation events. After producing a reasonable SWV that shares salient features with the events used in composite, a trajectory analysis is conducted and an along‐track vorticity budget is constructed. The results show that approximately 64.7% of the air particles related to SWV formation originate from four source regions outside the vortex. The largest contribution of cyclonic vorticity associated with the SWV formation (approximately 67.7%) comes from the lower levels southwest of the vortex and is due mainly to tilting. The second‐largest contribution (approximately 19.4%) is made by air particles that originate from the upper levels south of the SWV and is also due mainly to tilting. By contrast, for the other two sources (the upper levels west and southwest of the vortex), the convergence‐related horizontal shrinking generally dominates their cyclonic‐vorticity production. Overall, along the tracks of the air particles, vertical motions and water‐vapor phase transitions affect the vorticity variation significantly via modulating divergence‐related vorticity production/dissipation (i.e., the stretching effect), and this is vital for the SWV formation. [ABSTRACT FROM AUTHOR]

Aim Temporal transferability is an important issue when habitat models are used beyond the time frame corresponding to model development, but has not received enough attention, particularly in the context of habitat monitoring. While the combination of remote sensing technology and habitat modelling provides a useful tool for habitat monitoring, the effect of incorporating remotely sensed data on model transferability is unclear. Therefore, our objectives were to assess how different satellite-derived variables affect temporal transferability of habitat models and their usefulness for habitat monitoring. Location Wolong Nature Reserve, Sichuan Province, China. Methods We modelled giant panda habitat with the maximum entropy algorithm using panda presence data collected in two time periods and four different sets of predictor variables representing land surface phenology. Each predictor variable set contained either a time series of smoothed wide dynamic range vegetation index (WDRVI) or 11 phenology metrics, both derived from single-year or multi-year (i.e. 3-year) remotely sensed imagery acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS). We evaluated the ability of models obtained with these four variable sets to predict giant panda habitat within and across time periods by using threshold-independent and threshold-dependent evaluation methods and five indices of temporal transferability. Results Our results showed that models developed with the four variable sets were all useful for characterizing and monitoring giant panda habitat. However, the models developed using multi-year data exhibited significantly higher temporal transferability than those developed using single-year data. In addition, models developed with phenology metrics, especially when using multi-year data, exhibited significantly higher temporal transferability than those developed with the time series. Main conclusions The integration of land surface phenology, captured by high temporal resolution remotely sensed imagery, with habitat modelling constitutes a suitable tool for characterizing wildlife habitat and monitoring its temporal dynamics. Using multi-year phenology metrics reduces model complexity, multicollinearity among predictor variables and variability caused by interannual climatic fluctuations, thereby increasing the temporal transferability of models. This study provides useful guidance for habitat monitoring through the integration of remote sensing technology and habitat modelling, which may be useful for the conservation of the giant panda and many other species. [ABSTRACT FROM AUTHOR]