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The variability of renewable energy generation and its mismatch with demand may lead to curtailment issues, which necessitates the deployment of energy storage on a significantly larger scale. A‐CAES is a promising technology for its green ability and technology maturity to serve as grid's load following. However, previous research mainly focuses on system analysis and core component optimal, and the performance of A‐CAES when constructing with renewable resources has not been fully addressed. In this paper, a comprehensive evaluation on A‐CAES is presented based on an annual photovoltaic (PV) output in western China. The A‐CAES is modeled from the systematic perspective and the PV output is classified into four types (sunny, mostly‐sunny, mostly‐cloudy, and cloudy). First, the performance with different weather and different rated power of A‐CAES is fully investigated. Then, performance availability with different rated power has been proposed—the optimal condition occurs with average 5.936 MWh/day capacity and 53.49% efficiency on 1800 kW rated power. The evaluation framework is suitable for evaluating the role of CAES with other sources and such result provides a reference for A‐CAES designing and further application. [ABSTRACT FROM AUTHOR]

Due to global warming and other climate changes, it is increasingly important to study the response of regional environmental changes and dynamic changes in vegetation to climate change. Based on meteorological data from the last 60 years, this paper calculates the humidity index of western China under a wide range of long time series in different regions and explores the cross-correlation effect between series by offering a comparison with NDVI data, to analyze the cross-correlation between wet and dry changes and changes in vegetation in western China on a spatial scale. The results show that the spatial distribution of the interdecadal humidity index is different between different regions in western China. For example, the semi-arid and the semi-humid zones of the Weihe River region exhibit significant changes, while the Xinjiang and Qinghai–Tibet regions show a trend of constant wetness, on the whole, and the Sichuan and Yunnan–Guizhou regions are relatively humid and the distribution of wetness and dryness is relatively stable. The distribution of high and low values of the humidity index is very obvious and consistent with that of the distribution of desert bare land and precipitation in western China. In common with the distribution in the humidity index, the maximum correlation number between the NDVI and the humidity index in the whole western region is also significantly different in spatial distribution. There is a positive correlation between the NDVI and the humidity index in 99% of the study area. However, the delay in response time of the NDVI to changes in the humidity index in each region is inconsistent. For example, changes in the NDVI lag changes in the humidity index in the Menggan region by generally either 2 months or 5 months, while in the Sichuan region the delay in response time is generally 3 months. The variation and trend in dry and wet areas are closely related to the geographical location, climate zone, and topographic terrain, which may be the reason for the differences in the distribution of vegetation types and the response time to dry and wet changes. There is significant interaction between the humidity index and the vegetation type or precipitation distribution in western China. The positive correlation between the NDVI and the humidity index means that the positive effect is more sensitive, and the response of grassland is the most sensitive in the ecosystem. [ABSTRACT FROM AUTHOR]

Migrant workers in China and their children too frequently are treated as outsiders in the city. This paper explores and compares the opportunities for female Technical Vocational Education and Training (TVET) students in western rural areas of China. Learning from migrant girls how they perceive and evaluate benefits in and from their schooling provides us insights into how TVET played a role in achievements that rural migrant girls value and enact. The capability approach specified for education is used as a structure to assess TVET as experienced by its participants. This research shows that despite its deficiencies and obscurity within socio-economic structures, for the current generation of young rural migrant girls, TVET education was highly accessible, provided a singular opportunity and space to equip them with some skills and knowledge, and enhanced their capabilities to participate in a rapidly changing urbanizing economy. TVET education created changes on both individual and collective levels. Rural migrant girls' opportunities were constrained by unequal migration patterns and were structured along intersections of gender and ethnic lines. Implications for improving TVET policy include improved information flow, diversification of TVET curriculums, standardization of regulations, and increased opportunities for female and ethnic students. [ABSTRACT FROM AUTHOR]

In order to reveal the unsafe factors in the whole life cycle of the water diversion open channel in the dry and cold areas in western China, it is necessary to avoid frequent diseases of open channel in this area, which brings great losses to society and economy. In this paper, for the western dry and cold regions unique climatic and geological conditions, according to the Code for Design of Irrigation and Drainage Canal System Structures and combined with the expert consultation and the previous team’s study on characteristics of open channel diseases in this area, this paper established the safety index system of diversion channel and used the gray Euclid theoretical model to evaluate the safety of the whole life cycle. This paper used IAHP to solve the weight of each index, used gray Euclid association theory to determine the correlation between the indicators and finally got the relative gray Euclid weighted correlation degree of diversion channel safely sort. Taking four open channel sections in the dry and cold areas of western China for an example, the paper applied the gray Euclid model to evaluate the safety. The conclusion was in agreement with the actual situation. The research result shows that the model is effective and practical for the safety evaluation of the open channel in western China and it can provide an important basis for the safety management of open channel. [ABSTRACT FROM AUTHOR]

Macroseismic intensity data play an important role in seismic hazard analysis and in developing reliable earthquake loss models. This paper adopts an ellipse model to predict the macroseismic intensity attenuation in both the long-axis and the short-axis directions based on 136 earthquakes recorded throughout western China during 1970–2012. The geometric spreading and energy release of seismic waves are considered in the models proposed in this study. The proposed relation describes the macroseismic intensity simply as a function of the surface wave magnitude, source-to-site distance, and focal depth. This study adopts the focal depth that is not often considered in the current intensity prediction equations in China and uses different functional forms in the long- and short-axis directions. Based on residual analysis and evaluation, a more suitable macroseismic intensity predictive equation was established for western China, and it was compared and discussed with macroseismic intensity prediction equations of other researchers. [ABSTRACT FROM AUTHOR]

This paper quantifies urban land use eco-efficiency (ULUEE) and explores its improvement in the context of western China. We propose a hybrid model that includes the Super-slack-based measure model (Super-SBM) and a varying co-efficient panel model using data from 11 provincial cities in the western regions of China from 2000 to 2018. The results show that overall ULUEE, pure technical efficiency and scale efficiency were ecologically inefficient. Meanwhile, ULUEE differences between cities mainly reflect different levels of pure technical efficiency. Further, the linkage between urban population density and ULUEE can be expressed in inverted-U and U-shape curves, and most cities' industrial development positively affects ULUEE, while most cities' fixed asset investments negatively affect ULUEE. Moreover, land management institutions (LMIs) play a moderator role, shaping the main impacts of industrial development on ULUEE. Therefore, the findings suggest that improving ULUEE in the western region of China should focus on attracting inflows of highly skilled people, optimizing resource allocation, and guiding/regulating local government actions. [Display omitted] • Overall urban land use eco-efficiency (ULUEE), scale efficiency and pure technical efficiency of ULUEE are estimated and found to be eco-inefficient in the studied areas. • Slowing ULUEE improvement during the studied period results from slowing improvement of scale efficiency. • ULUEE differences between cities were mainly caused by pure technical efficiency. • LMI plays a moderator role in reducing the main impacts of industrial development on ULUEE. [ABSTRACT FROM AUTHOR]

As a consequence of the end-Permian mass extinction, microbes proliferated in the post-extinction shallow marine ecosystems, in which they grew as various microbially induced sedimentary structures (MISSs) in siliciclastic settings. This paper reports, for the first time, the discovery of abundant MISSs from the lowest Triassic sandstones of shallow-water margin origin in the Zhihema sections of the southern Qilianshan region, West China. The sandstones are characterized by well-developed cross-beddings and ripple marks, and a Claraia -dominated bivalve assemblage of middle-late Griesbachian age. These sedimentary structures, together with the bivalves, suggest a high-energy peritidal zone of a shoreface setting in a clastic shallow sea environment. Seven types of MISSs are recognized and described here: pictograph-like sand cracks/crack-fills, polygonal sand crack-fills, erosional remnants, multidirectional linear grooves, sinuous crack-fills, fusiform sand cracks/crack-fills, and leveled ripple marks. Most of the newly found MISSs are morphologically comparable with their ancient and modern counterparts. Detailed optical microscope and scanning electron microscope (SEM) analyses reveal that thin clayey laminae and filamentous mica grains are aligned parallel to bedding plane, and that the matrix-supported quartz grains, overall, are oriented; both of which are interpreted to indicate biogenic origin. The biogenic origin of these MISSs is reinforced by the presence of copious putative nanoglobules and filamentous biofilm-like organic objects in the interspaces of clay minerals in laminated layers. These nanometer-scale objects are interpreted as bacterial bodies or remains that have been replaced with inorganic minerals upon fossilization. The presence of MISSs on the northern margins of Paleo-Tethys indicates that the post-extinction microbial mats had expanded their distributions from low-latitude to moderate-high latitude regions. Moreover, unlike some previously reported microbial mats that contain very rare body and trace fossils, the southern Qilianshan MISSs were found in association with abundant vertical burrows and bivalves, suggesting that the MISS-forming microbial mats may have served as oases for trace-making organisms and opportunistic bivalves to flourish in shallow-marine habitats immediately after the end-Permian mass extinction. [ABSTRACT FROM AUTHOR]

• We analysed the influencing factors of urban eco-efficiency in Western China. • The US-SBM model and spatial econometric models were used for 84 cities' data. • Urban eco-efficiency showed a fluctuating upward trend during 2004–2017. • Economic development and urbanization had U-shaped impact on urban eco-efficiency. • Four explanatory variables showed a positive impact on urban eco-efficiency. Improving eco-efficiency can promote sustainable development. This study first evaluated the urban eco-efficiency of 84 cities in Western China from 2004 to 2017 by the undesirable-super-slack-based measure (US-SBM) and analysed their spatiotemporal characteristics, and then investigated its influencing factors using spatial econometric models. The results indicated that the urban eco-efficiency in Western China was at a relatively low level and showed a fluctuating upward trend with the highest average value of 0.65; however, capital cities of Western China have improved their eco-efficiency rapidly. Furthermore, there were obvious spatial spill-over impacts of the urban eco-efficiency in Western China. This paper also found that both the economic development level and urbanization level have "U" shaped impacts on Western China's urban eco-efficiency, which decreases at first and then rises. Similarly, increasing the proportion of secondary industry promotes urban eco-efficiency, and FDI, trade activities, improved environmental regulations as well as technological innovation capabilities have a positive impact on urban eco-efficiency in Western China. This paper also put forward corresponding policy suggestions to promote Western China's urban eco-efficiency. The present study may be helpful for policy-makers to balance economic development and environmental protection in Western China. [ABSTRACT FROM AUTHOR]

Marine Isotope Stage (MIS) 2 is mostly a cold period encompassing the Last Glacial Maximum (LGM), but the regional expression of MIS2 in arid areas of China is not well known. In this paper, we use high-resolution lacustrine pollen and grain-size records from Balikun Lake to infer vegetation, lake evolution, and climate in arid western China during MIS2. Our results suggest that: 1) the regional vegetation around Balikun was mainly dominated by desert and/or desert-steppe, and Balikun Lake was relatively shallow and experienced high aeolian input during MIS2; 2) distinctive runoff from mountain glacial meltwater in the eastern parts of the Balikun basin caused a high relative abundance of Artemisia pollen during the LGM (26.5–19.2 cal kyr BP), while simultaneously the desert areas expanded as indicated by the high abundance of desert shrubs (e.g., Elaeagnaceae, Rhamnaceae, Hippophae ). This cold and dry LGM climate triggered a substantial lowering of lake level; 3) an extremely cold and dry climate prevailing from 17.0 to 15.2 cal kyr BP, correlated with Heinrich event 1 (H1), would explain the low vegetation cover found then; and 4) the warm and humid Bølling/Allerød interstadial (BA: ca. 15– ca. 13 cal kyr BP) is clearly recorded in the Balikun region by the development of wetland herb communities (e.g., Poaceae, Cyperaceae, Typha ), and the lake level rose due to increased runoff. Our results challenge the traditional view of cold and wet climatic conditions and high lake levels in arid western China during the LGM, and we propose that changes in local temperature modulated by July insolation was an indispensable factor in triggering vegetation evolution in the Balikun region during MIS2. [ABSTRACT FROM AUTHOR]

Chengdu, located at the western edge of the Sichuan Basin, is the provincial capital of Sichuan Province. The fertile and well-watered basin has given the city a long and splendid history, which has left significant and lasting imprints on its urban form, landscape and cultural life. In the planned economy period, Chengdu serviced as the economic, cultural, logistical and technological center for southwest China, and built a competitive and broad industrial base which now helps the city maintain its leading position in the region. In 2007, Chengdu was assigned as one of two pioneer cities in coordinating urban–rural development. This paper introduces the urban development of Chengdu as a historical city, summarizes the city’s economic growth, urban spatial transformation and infrastructure construction as a major city in western China, and discusses its recent efforts in coordinating urban–rural development as a pioneering city in China. [ABSTRACT FROM AUTHOR]

The Xuebaoding deposit in the Songpan–Garzê orogenic belt, western China, spatially associated with the Xuebaoding granitic complex, is a unique pegmatite-type Sn–W–Be deposit within the giant Songpan–Garzê polymetallic belt. A lack of precise geochronological constraints on the timing of mineralization for this deposit has precluded definitive statements relating to a genetic link between ore formation and granitoid intrusion, up to now. To address the temporal relationship between the emplacement of granite and the spatially associated Sn–W–Be polymetallic mineralization in the Xuebaoding deposit, systematic cassiterite U–Pb and muscovite Ar–Ar dating were undertaken. U–Pb data of cassiterite analyzed by In-situ LA-MC-ICP-MS provided an isochron age of 193.6±6Ma (at 95% confidence level, MSWD=4). The 40Ar/39Ar dating on the muscovite intergrown with the cassiterite sample yielded a plateau age of 194.50±1.02Ma (MSWD=1.26), and an inverse isochron age of 194.53±1.05Ma (MSWD=1.34). Both the Ar–Ar dates overlap the U–Pb date within uncertainties, placing the timing of tin mineralization at ~193–194Ma. This is consistent with field geological relationships that show veins cutting marble and granite, and with previous Sm–Nd dating, within experimental error, for scheelite and indicates that Sn–W polymetallic mineralization at the Xuebaoding deposit occurred during the Early Jurassic. Combined with previous published trace element and REE data from the Xuebaoding granites and other ore minerals, as well as the timing of granite emplacement, the temporal and genetic associations between granite intrusion events and Sn–W mineralization of this deposit have been discussed in this paper. The results suggest that the Pankou granite is genetically related to the polymetallic mineralization in Xuebaoding Sn–W–Be deposit, and further demonstrate that the latest-phase of granitic intrusion is commonly favorable for Sn and/or W mineralization. Although the Pukou granite also exhibits close relationships with the ore formation in its spatial distribution and element characteristics, the possibility as a parent for this deposit is excluded duo to the time span from its emplacement to mineralization event that exceed the estimated life of modern geothermal systems (<1–2Ma). The constraints on the timing of mineralization and for the element and fluid source provide important insight into the genesis of the Xuebaoding deposit. [ABSTRACT FROM AUTHOR]

Background: In China, ethnic minorities often live in frontier areas and have a relatively small population size, and tremendous social transitions have enlarged the gap between eastern and western China, with western China being home to 44 ethnic minority groups. These three disadvantages have health impacts. Examining ethnicity and health inequality in the context of western China is therefore essential.Methods: This paper is based on data from the 2010 China Survey of Social Change (CSSC2010), which was conducted in 12 provinces, autonomous regions and province-level municipalities in western China and had a sample size of 10,819. We examined self-rated health and disparities in self-rated health between ethnic minorities and Han Chinese in the context of western China. Self-rated health was coded as poor or good, and ethnicity was coded as ethnic minority or Han Chinese. Ethnic differences in self-rated health was examined by using binary logistic regression. Associations among sociodemographic variables, SES variable, health behaviour variable, health problem variables and self-rated health were also explored.Results: Fourteen percent of respondents reported their health to be poor. A total of 15.75% of ethnic minorities and 13.43% of Han Chinese respondents reported their health to be poor, indicating a difference in self-rated health between ethnic minorities and Han Chinese. Age, gender, marital status, education, alcohol, and health problems were the main factors that affected differences in self-rated health.Conclusion: In western China, there were obvious ethnic disparities in self-rated health. Elderly ethnic minorities, non-partnered ethnic minorities, ethnic minorities with an educational level lower than middle school, and ethnic minorities with chronic disease had higher odds of poor self-rated health. [ABSTRACT FROM AUTHOR]

Since the implementation of the great western development strategy in 2000, the ecological environment in the western region of China has been significantly improved. In order to explore the temporal and spatial characteristics of vegetation coverage in the western region, this paper adopted the method of Maximum Value Composite (MVC) to obtain the mean Normalized Difference Vegetation Index (NDVI) of vegetation on the basis of the Moderate-resolution Imaging Spector audiometer (MODIS) data of 2000/2005/2010/2015/2018. Thereafter, the spatio-temporal differentiation characteristics of vegetation in western China were analyzed. The results show that: (1) According to the time characteristics of vegetation coverage in the western region, the average annual NDVI value of vegetation coverage in the growing season in the western region fluctuated between 0.12 and 0.15, among which that of 2000 to 2010 fluctuated more greatly but did not show obvious change trend. (2) Based on Sen trend and Mann-Kendall test analysis, the area of vegetation coverage improvement in the western region from 2000 to 2018 was larger than that of significant vegetation degradation. (3) From the perspective of global autocorrelation coefficient, Moran's I values were all positive from 2000 to 2018, which indicates that the vegetation coverage in the west showed strong positive autocorrelation in each period. According to the average value and coefficient of variation of vegetation coverage, the vegetation coverage was lower in 2000, its internal variation was smaller, and the vegetation coverage increased with time. According to the local spatial autocorrelation analysis, the vegetation coverage levels in different regions varied greatly. (4) The standard deviation ellipse method was used to study the spatial distribution and directional transformation of vegetation. It makes the result more intuitive, and the three levels of gravity center shift, direction shift, and angle shift were considered: the vegetation growth condition in the spatial aggregation area improved in 2015; the standard deviation ellipses in 2000 and 2018 overlapped and shifted eastward, which indicates that the vegetation coverage conditions in the two years were similar and got ameliorated. [ABSTRACT FROM AUTHOR]