Central China Region Research Articles

Spatiotemporal variations and priority ranking of emerging contaminants in nanwan reservoir: A case study from the agricultural region in huaihe river basin in China

The presence of emerging contaminants (ECs) in drinking water sources is an increasing concern, yet limited data exists on their occurrence and risk in the upper Huaihe River Basin, an important agricultural region in Central China. This study investigated 70 ECs, including pesticide and antibiotics in surface water from drinking water source areas in Nanwan Reservoir along the upper reaches of the Huaihe River Basin to prioritize the ECs based on ecological risk and health risk assessment. A total of 66 ECs were detected in the surface water at least once at the selected 38 sampling sites, with concentrations ranging from 0.04 to 2508 ng/L. Ecological risk assessment using the risk quotient (RQ) method revealed high risks (RQ > 1) from 7 ECs in the dry season and 15 ECs in the wet season, with triazine pesticides as the main contributors. Non-carcinogenic risks were below negligible levels, but carcinogenic risks from neonicotinoid and carbamate pesticides and macrolide antibiotics were concerning for teenagers. Ciprofloxacin exhibited a high level of resistance risk during the wet season. A multi-indicator prioritization approach integrating occurrence, risk, and chemical property data ranked 6 pesticides and 3 antibiotics as priority pollutants. The results highlight EC contamination of drinking water sources in this agriculturally-intensive region and the need for targeted monitoring and management to protect water quality.

Marketization and corporate cash holdings: Role of financial constraint alleviation

AbstractThis study examines the relationship between marketization and corporate cash holdings. Using a sample of the Chinese stock market spanning from 2007 to 2020, our empirical results show that marketization negatively affects corporate cash holdings. This effect is more pronounced for firms in the eastern and central regions of China and Chinese Growth Enterprise Market (GEM). Additionally, our study finds that investment opportunities and state‐owned features of firms play moderating roles in the effect of marketization on firms' cash holdings. State‐owned enterprises (SOEs) are less affected by marketization; however, the more investment opportunities a firm has, the greater is the negative impact of marketization on its cash holdings. Finally, we find that marketization can affect corporate cash holdings through firms' financing constraints. These results are robust to various tests and alternative explanations.

Long-range transport impact of a severe dust storm over the Yangtze River Basin region and its modeling sensitivity to dust emission scheme

Dust storms frequently occur in the spring over East Asia, affecting southern Mongolia and northeast China. An exceptionally powerful dust storm occurred in East Asia from March 14th to March 18th, 2021. To investigate the ability of climate models to simulate severe dust storms, we employed the Weather Research Forecast model coupled with chemistry (WRF-Chem) with Goddard Chemistry Aerosol Radiation and Transport (GOCART), SHAO and KOK dust emission schemes to simulate the evolution of this event and to characterize dust aerosols long-range transport. Results showed that this storm was caused by a Mongolian cyclone depicted at 850 hPa with a cold front, which swept dust aerosols southeastward across southern Mongolia to northeast China. Model evaluation with satellite-retrieved Aerosol Optical Depth (AOD) and observational PM10 concentrations revealed that the SHAO dust emission scheme performed better in simulating spatial and temporal distribution of AOD over the Gobi Desert (GD) but overestimated them over Taklimakan Desert (TD). In contrast, the GOCART dust emission scheme underestimated AOD over most areas except the Taklimakan Desert; the KOK dust emission scheme overestimated them over both TD and GD. Overall, the SHAO dust emission scheme had good performance in simulating the surface PM10 concentrations over the Yangtze River Basin (YRB) and depicted an increase in PM10 concentrations, which denoted the transport of dust aerosols over YRB. As a better description of the physical process of dust emission flux over the eastern region of the Gobi Desert, the SHAO dust emission scheme depicted well the spatial and temporal evolution of dust plume episodes, especially over northeast China and YRB. The significant differences in dust emission fluxes between the three dust emission schemes were attributed to the sensitivity of threshold friction velocity and erodibility factor. Thereunto, the SHAO dust emission scheme incorporated well soil particle size distribution and threshold velocity to produce the dust emission flux, which allowed higher dust emission flux over the eastern GD and under strong southwesterly transported dust aerosols to East Central China's region of North China Plain (NCP) and YRB. This study will help further the simulation of extreme dust events more accurately and the exploration of climate change's effect on dust events over East Asia.

Spatiotemporal Variation of Soil Erosion in the Northern Foothills of the Qinling Mountains Using the RUSLE Model

The Qinling region in central China, known as the ‘Dragon Vein of China’, is a vital ecological barrier facing significant soil erosion challenges. This study aims to enhance soil erosion management and analyse the spatiotemporal changes of soil erosion in the northern foothills of the Qinling Mountains. We collected data on precipitation, terrain, land use types, and soil in the designated region. Using GIS technology and the Revised Universal Soil Loss Equation (RUSLE) model, we created a detailed soil erosion map and analysed its evolution from 2018 to 2022. Results show a significant reduction in soil erosion in 2020–2021 despite a general upward trend in other years. Innovation includes integrating remote sensing with RUSLE for high-precision mapping and introducing a hierarchical approach for erosion risk assessment. The study found erosion peaks in summer and autumn, with higher levels in the southern parts compared to the northern parts. Influential factors include climate variables, human activities, soil, and vegetation types. The average soil erosion modulus in 2023 is 233.515 t/(km2·a), with total soil erosion of 85,233.046 t/a, mainly concentrated in the valley and mountain basin areas. This research provides a theoretical basis for improving the natural environment and implementing comprehensive soil and water conservation measures in the Qinling region, offering a model for similar ecological regions globally.

Disparity in Guideline-Based Antidiabetic Drugs Prescribing for Type 2 Diabetes Patients in Primary Healthcare Facilities Across China, 2017-2019.

The purpose of this study is to evaluate the pattern, appropriateness, and cost of antidiabetic drugs prescribed for patients with Type 2 diabetes at primary healthcare facilities (PHFs) in China. We collected outpatient-visit prescriptions from 363 PHFs in 31 cities covering eastern, central, and western regions of China. The visits of adult patients with Type 2 diabetes diagnosis were collected and classified the antidiabetic medication pattern of each patient use as recommended or non-recommended according to Chinese guidelines. We then calculated the proportion of guideline-recommended patterns and the average monthly cost for each pattern, overall and by region. Of 33 519 prescriptions for Type 2 diabetes, most (73.9%) were for guideline-recommended antidiabetic treatments. The proportion of guideline-recommended prescriptions varied by region (eastern [75.9%], central [87.5%], and western [59.7%]). Metformin monotherapy was the most common guideline-recommended treatment in all three regions (eastern [20.1%], central [28.0%], and western [24.6%]). The most common non-guideline-recommended treatments were monotherapy of insulin (eastern [16.5%], central [5.1%], and western [25.7%]) and traditional Chinese antidiabetic medicines (eastern [5.6%], central [5.7%], and western [11.1%]). The average monthly costs were lower for guideline-recommended treatments compared to non-recommended treatments in all regions (eastern [13.6 ± 15.4 USD vs. 28.1 ± 22.0 USD], central [9.8 ± 10.9 USD vs. 28.7 ± 19.4 USD], and western [17.9 ± 21.4 USD vs. 30.3 ± 23.6 USD]). The majority of patients with Type 2 diabetes received guideline-recommended antidiabetic medications at PHFs in China, with only half of the prescriptions containing guideline-recommended metformin. Utilization of guideline-recommended therapies differed across regions. Tailored interventions to promote evidence-based antidiabetic prescribing are urgently needed, especially in the undeveloped western region.

The relationship between peer support and sleep quality among Chinese college students: the mediating role of physical exercise atmosphere and the moderating effect of eHealth literacy.

Poor sleep quality has emerged as a prevalent health issue among college students. This study aims to explore the mechanism of sleep quality among college students by constructing a moderated mediation model. The Peer Support Scale, Physical Exercise Atmosphere Scale, eHealth Literacy Scale and Pittsburgh Sleep Quality Index were used to conduct a survey and analysis on 1,085 questionnaires, which were distributed among students from four universities in the northwest, northeast and central regions of China. (1) A significant pairwise correlation exists between peer support, physical exercise atmosphere, eHealth literacy and sleep quality (P < 0.001); (2) Physical exercise atmosphere plays a mediating role between peer support and sleep quality, with a mediating effect accounting for 28.08%; (3) eHealth literacy can significantly moderate the strength of the relationships between peer support and exercise atmosphere, between peer support and sleep quality, and between physical exercise atmosphere and sleep quality. This study revealed the relationship between peer support and sleep quality among college students and its influencing mechanism, and provided theoretical and practical basis for improving college students' sleep quality from the perspectives of peer support, physical exercise atmosphere, and eHealth literacy.

Patterns of environmental regulation and green innovation in China

Green technology innovation is an important means to achieve sustainable development. The study is an exploration of the bilateral perspective on the relationship between different types of environmental regulations and green innovation. Based on the data set of 30 provinces in China from 2006 to 2018, the two-sided effects of command-and-control environmental regulation and market-based environmental regulation on green innovation are analysed and the net effects are calculated by using the two-tier stochastic frontier models. First, empirical research shows that the effects of command-and-control environmental regulation and market-based environmental regulation on green innovation are both highlighted by negative characteristics. Command-and-control environmental regulation has a smaller effect on green innovation, with an average positive effect of 0.00005, which is smaller than the average negative effect of 0.0008. Meanwhile, the positive effect of market-based environmental regulation on green innovation is 0.00291, smaller than the negative effect of 0.00461. Second, the negative impact of command-and-control environmental regulation on green innovation underwent a "back-to-N" change process in 2006–2018, while the negative effect of market-based environmental regulation on green innovation did not decline until after 2011. Third, the provinces where command-and-control environmental regulation policies have a greater negative effect are concentrated in the energy-intensive regions of central and western China, while the provinces where market-based environmental regulation policies can promote green innovation are from the energy-intensive or developed eastern regions of China. Based on the research conclusions, to better promote green innovation, there is a need to implement environmental regulatory policies that address regional differences and to establish a national system of green innovation markets.

Current status of palliative care for patients with unresectable metastatic colorectal cancer in China: a questionnaire-based survey

Objective: To analyze the current adoption of palliative care by patients with unresectable metastatic colorectal cancer (mCRC) in China. Methods: From 1 March 2023 to 30 June 2023, a questionnaire survey was conducted by random sampling. An exclusive research platform for the Blue Book on Clinical Diagnosis and Treatment of Metastatic Colorectal Cancer. An online questionnaire was sent to medical oncologists (including chief physicians, associate chief physicians, attending physicians and residents) in general hospitals and oncology hospitals in four major regions of East, Central, South and Northeast China. The questionnaire contained 28 questions requesting basic information about doctors, the number of patients with mCRC, the status of treatment from first to fourth line and beyond, points concerning treatment of pain in patients with mCRC, and expectations for the future. A medical team was responsible for the quality control of data collected, whereas statisticians performed the data cleaning and sorting and statistical analysis. Results: A total of 300 clinical questionnaires were collected, including 217 (72%) from doctors in general hospitals and 83 (28%) from doctors in oncology hospitals. Senior physicians (including associate chief physicians and chief physicians) accounted for 65% of the respondents, attending physicians 30%, and residents 5%. Within 3 months (average for each month), 46.4±26.6% patients were diagnosed with recurrent or unresectable mCRC by each physician, 51.6±26.8% of the patients being in cancer hospitals and 44.4±26.3% in general hospitals. One hundred percent of patients receiving first-line treatment received palliative care, as did 80.3% of those receiving second-line treatment, 58.2% of those receiving third-line treatment, and 35.1% of those receiving ≥fourth-line treatment. The primary factor governing selection of first-line treatment was guideline recommendations, whereas comorbidities and the patients' physical status dictated second line to fourth line treatment. Standard first-line treatment was administered to 93.8% of eligible patients, standard second-line treatment to 94.3%; and standard third-line treatment to 73.5%. First-line therapy included targeted therapy in 63.6% of patients and immunotherapy in 2.8%; second-line therapy included targeted therapy in 63.0% of patients and immunotherapy in 2.0%; third-line therapy included targeted therapy in 59.2% of patients and immunotherapy in 2.2%; and fourth-line therapy included targeted therapy in 48.7% of patients and immunotherapy in 3.1%. First-line treatment lasted an average of 9.6 months, second-line treatment 6.7 months, third-line treatment 4.9 months, and fourth-line treatment 3.7 months. More than 70% of the patients maintained a good quality of life after receiving first and second-line treatment and more than 60% of them had ECOG performance scores of 0-1. After receiving third- and fourth-line treatment, 50%-60% of patients maintained a good quality of life and 40%-50% of them maintained ECOG performance scores of 0-1. The survey also revealed that the main deficiencies in treatment were limited effectiveness of third-line treatment, insufficient availability and opportunity for clinical research, popularity of new drugs or new drug combination strategies, and limited channels for participation in multidisciplinary diagnosis and treatment. Clinicians reported looking forward to participating in more clinical research on new drugs, hearing about the experience of experts in the field, and discovery of new targets and new drugs that increased the options for posterior line treatment of colorectal cancer. Conclusions: This report objectively summarizes the current situation, treatment difficulties, and expectations of frontline physicians concerning management of mCRC, thus providing a basis for decision-making and future direction for the diagnosis and research on treatment of mCRC.

Spatiotemporal patterns in persistent precipitation extremes of the Chinese mainland (1961–2022) and association with the dynamic factors

Previous studies on extreme precipitation events have primarily focused on the intensity of such events during fixed periods, without considering the entirety of extreme precipitation events and conducting a comprehensive examination of the intensity and frequency of more disastrous persistent extreme precipitation (PEP) events. In this paper, persistent extreme precipitation indices (PEPIs) related to intensity, frequency, duration, and contribution rates were constructed, utilizing a gridded daily precipitation dataset and atmospheric circulation indices data from China for the period 1961–2022 to analyze the spatial distribution, spatiotemporal trends, and seasonal patterns and variations of PEPIs across different regions of China and the potential impact of the dynamic factors on the spatiotemporal variations of PEPIs. The results are crucial for effectively predicting future changes and informing planning for adaptation strategies: From 1961 to 2022, (1) China's PEP pattern displays distinct regional variations. PEP has been prevalent in Western Arid (Semi-Arid) Zone (WAS) and Qinghai-Tibet Plateau (QT) regions, with higher occurrence frequency, duration, and contribution rates to total extreme precipitation (44.91% and 42.01%) and overall precipitation (26.35% and 29.08%). Conversely, the humid eastern regions exhibit greater event intensity. (2) Intensity-related PEPIs show a significant increase, while the frequency and contribution rate-related PEPIs tend to decrease, indicating less frequent but more concentrated PEP events. (3) Seasonal distribution of PEP events shows a primary concentration in QT, North China (N), the Eastern arid zone (EA), and Northeast China (NE) from June to September and they occur more frequently during spring and summer in Central (C) and South China (S) regions. Summer variations predominantly account for annual PEP variability and trends. (4) WPSHII, SCSSHII, WPWPSII, APVII, NHPVII, NINO3 predominantly affect the WAS, QT, NE, C, and S regions, with WPSHII having the broadest impact, notably on the QT, C, S, and NE regions. In the WAS region during autumn, the interaction of NAO and WPSHII explains 72% of the intensity of PEP events.

Exploring the Supporting Role of Finance in the Development of Clean Energy in China Based on the Panel Vector Autoregressive Model

The efficient development and widespread utilization of clean energy hold global significance, particularly for developing countries like China, which has committed to carbon peak and neutrality targets. In this context, the financial sector plays a crucial role in supporting the renewable energy industry, ensuring a reliable energy supply for economic growth. To statistically assess the impact of financial characteristics—such as financial efficiency, financial size, and green finance—this paper employs a panel vector autoregressive (PVAR) model with province-level data from China spanning the period 1991 to 2018. The key findings demonstrate that (1) financial factors significantly contribute to the development of clean energy in China, and among these factors, financial scale has a greater impact than financial efficiency and green finance; (2) there are distinct regional variations in how financial development affects the clean energy sector, and the role of financial scale is particularly pronounced in the central and western regions of China while the impact of financial efficiency on the clean energy industry is not significant across all regions; and (3) other drivers—including industrial structure, financial expenditure, and technological advancements—also spur the growth of the clean energy industry. However, due to diminishing marginal effects, the forces driving its growth may gradually diminish. Therefore, the article proposes critical policy suggestions for promoting clean energy development in China. These policies should consider the regional context and address both financial and non-financial aspects. Understanding the interplay between finance, regional dynamics, and clean energy development is crucial for achieving sustainable and resilient energy systems in China.

A preliminary integrated analysis of regional paleoclimate variations in China over the past ∼ 21 ka

In this study, we employ biological, geochemical and mineral, and physical proxies to quantitatively and semi-quantitatively reconstruct regional paleoclimate variations in China over the past ∼21 thousand years (ka). We have constructed state-of-the-art transfer functions between proxies and climatic variables in East Asia, revealing substantial paleoclimate variability, and demonstrate significant diversity of paleoclimate variations in regions of China over the past ∼21 ka. Compared with observational data between 1961 and 1990, averaged mean annual temperature (MAT) was ∼5 °C (3–8 °C) lower during the Last Glacial Maximum (LGM, ∼21 ± 3 ka), and ∼ 2 °C (1–3 °C) higher during Holocene Optimum (HO, ±9 ka) in China; while averaged mean annual precipitation (MAP) and averaged summer precipitation varied between 30 and 150%, with enhanced seasonality during the warmer Holocene (8–5 ka). Our quantitative and semi-quantitative paleoclimate reconstructions reveal both similarities and contrasts with previous studies of regional temperature and precipitation variability. The most remarkable paleoclimate variability is recorded in the transitional zone between the humid monsoon and arid desert regions of central and northern China. We conducted a dynamic downscaling paleoclimate simulation with a regional climate model (RegCM4), using the output from the fully-forced transient simulation of the global climate (TraCE-21 K) as the prescribed boundary conditions, to simulate regional climate changes at high spatial resolution in China over the past ∼21 ka. The results improve paleoclimate simulations at regional scales, but reveal differences in comparison with TraCE-21 K, thereby highlighting uncertainties in the simulation modeling. Moreover, we compare proxy-based paleoclimate reconstructions and the output of TraCE-21 K to identify inconsistencies in relation to regional paleoclimate variations, and confirm a generally consistent warming trend in MAT from the LGM to the HO followed by a cooling trend during the late Holocene. An overall increase in both annual and summer precipitation is observed from LGM to Holocene. This general paleoclimate pattern is likely to have been driven by northern hemisphere ice volume and atmospheric greenhouse gas concentrations (GHGs) during the last deglaciation, and boreal summer insolation during the Holocene. This study represents the first attempt to use multi sources and large datasets of proxy reconstructions and numerical simulations to evaluate regional paleoclimate variability in China since the LGM. Our research provides a comprehensive overview of climate change over the past 21 ka and underscores the critical importance of conducting high-resolution simulations and quantitative paleoclimate studies. This approach is essential for deciphering patterns of paleoclimate change that are currently poorly defined.

Breaking the financial bottleneck of local universities of China: an analysis of the current situation of university intellectual property

PurposeWith the global economic slowdown in 2023, most universities in the central and western regions of China may face the problem of shortage of government financial funding, which is directly related to the development of science and technology of the universities. With the support of the local government, most of the ordinary universities have shifted attention to the transfer and transformation of intellectual property based on school-enterprise cooperation, hoping to seek more commercialization income as an extra source of income. Therefore, this paper aimed to study the current situation of university intellectual property, i.e. the reserve and distribution of transferable patents, discipline distribution of patents, and regional cooperation of university patents.Design/methodology/approachA patent database of 10 key universities in Henan Province of China from 2012 to 2021 was established. The evaluation indicator model by the Entropy method was conducted to reveal the interaction mechanism between quantity indicators, quality indicators, and value indicators. Based on the data analysis, the development direction of the discipline construction and school-enterprise cooperation for local universities was clear.FindingsThe findings indicated that the number of patent applications from ten key universities in Henan Province has been increasing rapidly over the years. The trend for authorized invention patents has remained relatively stable. Compared with the patent applications and authorizations, the growth of transferable patents was notably slow. The significance of strategic layout of dominant disciplines and related high-value patents was not appreciated enough by Chinese government and universities. There was a large difference of dominant disciplines between 10 key universities, and the patent level of each university was directly proportional to the number of dominant disciplines. The university patent level heavily relied on the researchers' contributions and the distribution mechanism of scientific research resources within the university. Guangdong Province and the Yangtze River Delta of China, being economically developed regions, exhibited the most active engagement in patent technology cooperation. Conversely, the central and western regions displayed relatively lower participation in high-value patent research and development.Research limitations/implicationsThis study can provide a unique perspective to understand and solve the financial bottleneck problem of ordinary universities in the central and western regions of China. The discipline construction and school-enterprise cooperation are just one of the existing schemes, but it still cannot solve the financial problems faced by local universities in China towards the government.Practical implicationsThe findings of this study can serve as a foundation for further investigation into policies aimed at improving the financial problems of ordinary universities in the central and western regions of China.Originality/valueAs an important attempt, the study tried to focus the financial problem of universities in the central and western regions of China based on the evaluation of the current situation of university intellectual property. This research findings are of great value in finding optimal layout between university patents, disciplines and school-enterprise cooperation.

Investigation into the Factors Affecting the Green Consumption Behavior of China Rural Residents in the Context of Dual Carbon

The achievement of the dual-carbon objective and China’s green and sustainable development are both heavily reliant on green consumption. This research paper employs the Likert scale method to construct a questionnaire encompassing internal and external factors that influence green consumption behavior, as well as various types of consumption behavior. It then administers the questionnaire to 1004 rural residents residing in the eastern, central, western, and northeastern regions of China, with the objective of gathering pertinent data on green consumption behavior. Drawing from the aforementioned, structural equation modeling was employed to investigate the impact of three external factors—market incentives, social pressure, and information boost—and two internal factors—environmental awareness and psychological factors—on diverse forms of green consumption behavior. The objective was to identify the most influential factors of various green consumption behaviors to facilitate the effective promotion of green consumption. The research findings indicate that internal factors exert a more substantial influence on green consumption behaviors compared to external factors. Specifically, market incentives ranks highest among the external determinants of green consumption behavior, and environmental protection cognition rank highest among the internal determinants of green consumption behavior.

The Epidemiological Characteristics and Spatiotemporal Clustering of Measles - China, 2005-2022.

In recent years, the incidence of measles in China has consistently remained below 1 per 100,000 population, yet the disease has not been eliminated. This study aims to comprehensively analyze the epidemiological characteristics of measles from 2005 to 2022, identify high-risk populations and areas, and propose targeted interventions. We utilized data from the China Disease Prevention and Control Information System for our comprehensive analysis. Spatial autocorrelation was employed to examine the spatial clustering of measles, while spatiotemporal scanning analysis was used to detect spatiotemporal clustering to describe measles epidemiology during the study period. Between 2005 and 2022, 732,218 measles cases were reported in China. Overall, the incidence of measles exhibited a downward trend, particularly during the periods of 2008-2011 and 2015-2022. In 2022, the incidence rate reached its historical low at 0.039 per 100,000 population. Measles predominantly affects young children. Since 2017, global spatial clustering has diminished, although hotspot areas persist in the western provinces. Spatial-temporal scanning identified a high-incidence cluster from 2005 to 2008, comprising 15 provinces in the western, central, and northern regions of China. Conversely, from 2016 to 2022, a low-incidence cluster was detected in the southern and central provinces. China has made significant progress in measles prevention and control. The recent low incidence and absence of substantial spatiotemporal clustering indicate that China is nearing measles elimination. However, there is a continuing need to enhance prevention and control efforts among very young children and in historic incidence hotspots in western provinces. Additionally, improving the diagnosis of vaccine-associated rash illnesses is essential.

A spatiotemporal analysis of personal casualty accidents in China's electric power industry

The electric power industry in China has experienced significant growth in recent years. Despite efforts to improve safety management in the industry, accidents still occur frequently. This study aimed to analyze the personal casualty accidents in the electric power industry from 2012 to 2021. Specific methods used include descriptive analysis, principal component analysis, and Theil index model. The results indicated that fall, electric shock, and collapse were the primary types of accidents, accounting for 59.65 % of all accidents. Accidents were higher in April and August, but lower in February. While the accident rate was relatively low on Mondays, the fatality rate was higher on Mondays, Thursdays, and Fridays. Taking into account accidents, workload, and labor, we found that Ningxia, Hainan, and Guangxi exhibited subpar levels of safety management within the electric power industry. The overall difference in the number of deaths in 31 provinces was significant in 2012 and 2016. It was significantly reduced in 2021. In terms of the proportion of intraregional and interregional differences, there were significant differences in the number of accidents and fatalities between provinces in the Central China and North China regions. This study provides valuable insights for enterprises to formulate accident prevention strategies and for the government to develop relevant policies.

A Review of Stability of Dam Structures in Coal Mine Underground Reservoirs

Coal has remained the primary component of China’s energy structure, and high-intensity extraction has continued in the central and western coal-producing regions of China. In contrast to the abundant coal resources, water resources have become extremely scarce in these regions, creating a conflict between coal resource extraction and water resource conservation. The coal mine underground reservoir (CMUR), as a typical technology for combined coal and water extraction and water-preserving coal mining, has been applied in numerous mines in central and western China. This effectively alleviates water resource shortages and achieves the goal of water resource conservation. The CMURs utilizes the goaf created by longwall mining as the water storage space. The reservoir dam structure comprises coal pillars, which serve as protective coal pillars in the mining area, and artificial dam structures that filled the gaps between these coal pillars. The stability of the dam structure under the complex stress effects of hydraulic coupling has been identified as the key to maintaining the safe operation of the CMUR. The mechanical properties, stress field, fracture field, and seepage field (“three fields”) change mechanisms, as well as the research results on size optimization of coal pillar dams and artificial dams in CMURs, were systematically reviewed. The core content included the instability and failure mechanisms of dam structures under the comprehensive coupling effects of factors such as dry–wet cycles of mine water, long-term immersion, chemical effects of high-salinity water, dynamic and static loads, and cyclic loads. This paper is considered to have certain reference value for the study of the stability of dam structures in CMURs and to provide some guidance for the safe operation of CMURs.

Spatiotemporal carbon sequestration by forests among counties and grids in China

Top-down emission reduction target setting results in inability of local governments to develop differentiated plans for emission reduction. Forests have received considerable attention as an important source of carbon sequestration, especially following China's commitment to carbon neutrality. However, studies have paid little attention to spatiotemporal differences of downscale forest carbon sequestration in China over the long term due to data limitations, while also ignoring the large differences in forest carbon sequestration per unit area among different regions. Here, a basic dataset of forest carbon sequestration among counties and grids in China is constructed and the temporal drivers and spatial differences of forest carbon sequestration were investigated from the perspectives of counties' administrative boundaries and 0.5 by 0.5 degree grid combining modelling, GIS spatial analysis and a decomposition method. Changes in forest land use between 2000 and 2020 were also analysed. The results highlight the importance of forests in managing carbon sequestration among all types of terrestrial vegetation and the differences in forest carbon sequestration per unit area. The scale effect increased forest carbon sequestration in the first two periods (2000–2005 and 2005–2010), followed by a decrease since 2010. The intensity effect promoted carbon sequestration; in particular, a dramatic increase was observed from the second (2005–2010) to the third period (2010–2015). The heterogeneity of the scale effect of forest carbon sequestration increased compared to that of the intensity effect, both from administrative and geographical divisions. The scale and intensity effects of counties located in the northern regions of northeast China enhanced forest carbon sequestration, while counties located in southern and central China inhibited it during the study period. The scale effect of grids changed from enhanced to inhibited forest carbon sequestration mainly in northeast China near 120°E, whereas the intensity effect of grids increased from inland regions in central China to eastern coastal regions during the study period. This study provides references for policymakers to set differentiated emission reduction targets considering the local forest carbon sequestration.

Nighttime Warming Reduced Copper Concentration and Accumulation in Wheat Grown in Copper-Contaminated Soil by Affecting Physiological Traits

The changes in biomass (including yield), copper (Cu) concentration, and the accumulation of wheat (Triticum aestivum. L) in response to soil Cu pollution under nighttime warming had still not been explored. Hence, this study was carried out, and these variations were analyzed from a physiological perspective. Pot trials were performed at two levels of ambient temperatures (no-warming (NT) and average nighttime warming of 0.28 °C (WT)) and two levels of soil Cu concentrations (control check without Cu application (CK) and 100 mg/kg Cu application (Cu)). Soil was collected from the carbonate cinnamon soil region of central China. The warming effects of the passive nighttime warming system were prominent, and the average increment was 0.28 °C. Antioxidant enzyme activities were promoted by warming (p &lt; 0.05) and Cu. The highest yield was achieved in NT-Cu, mainly attributed to relatively strong root activity and photosynthesis caused by supplemental Cu, but the Cu concentration in its grains was close to the threshold (10 mg/kg) for Cu concentration in foodstuff and could present a potential food safety risk. Though nighttime warming did not increase the total biomass and yield of wheat, it decreased the Cu accumulation of wheat grown in Cu-contaminated soil, especially in grains. Moreover, WT-CK and WT-Cu increased the Cu concentration in the roots and glumes and reduced the Cu concentration in grains by 13.09% and 55.84%, respectively, probably because of a lower transpiration rate. Among them, the Cu concentration of grains in WT-Cu was the lowest and significantly lower than other applications. Our findings reveal that nighttime warming has the potential to reduce the Cu risk of grains in wheat grown in the Cu-contaminated carbonate cinnamon soil region of central China and could then provide a theoretical reference for risk assessment of food quality for wheat subjected to dual stress from nighttime warming and Cu pollution.

The diversity and risk of potential pathogenic bacteria on the surface of glaciers in the southeastern Tibetan Plateau

Glaciers, which constitute the world's largest global freshwater reservoir, are also natural microbial repositories. The frequent pandemic in recent years underscored the potential biosafety risks associated with the release of microorganisms from the accelerated melting of glaciers due to global warming. However, the characteristics of pathogenic microorganisms in glaciers are not well understood. The glacier surface is the primary area where glacier melting occurs that is often the main subject of research on the dynamics of pathogenic microbial communities in efforts to assess glacier biosafety risks and devise preventive measures. In this study, high-throughput sequencing and quantitative polymerase chain reaction methods were employed in analyses of the composition and quantities of potential pathogenic bacteria on the surfaces of glaciers in the southeastern Tibetan Plateau. The study identified 441 potential pathogenic species ranging from 215 to 4.39 × 1011 copies/g, with notable seasonal and environmental variations being found in the composition and quantity of potential pathogens. The highest level of diversity was observed in April and snow, while the highest quantities were observed in October and cryoconite. Host analysis revealed that >70 % of the species were pathogens affecting animals, with the highest proportion of zoonotic pathogens being observed in April. Analysis of aerosols and glacial meltwater dispersion suggested that these microbes originated from West Asia, primarily affecting the central and southern regions of China. Null model analysis indicated that the assembly of potential pathogenic microbial communities on glacier surfaces was largely governed by deterministic processes. In conclusion, potential pathogenic bacteria on glacier surfaces mainly originated from the snow and exhibited significant temporal and spatial variation patterns. These findings can be used to enhance researchers' ability to predict potential biosafety risks associated with pathogenic bacteria in glaciers and to prevent their negative impact on populations and ecological systems.

Analysis of dynamic relationship between agricultural products circulation service industry and circulation efficiency in less developed regions: based on data from Western China

The market circulation system for agricultural products in less-developed regions lags behind; it fails to meet the requirements for efficient circulation. Therefore, it is crucial to explore the dynamic relationship between the Agricultural Products Circulation (APC) service industry and circulation efficiency. Using panel data from 29 regions in China, the entropy method measured the Development Level (DL) of the APC service industry, while the non-oriented super-efficiency Slacks-Based Measure (SBM) model was employed to assess the APC efficiency. A Panel Vector Autoregressive (PVAR) model was built for estimation. The impulse response function and variance decomposition were utilized to analyze the differences in the DL of the APC service industry, circulation efficiency, and their interaction mechanism across the Western, Central, and Eastern regions of China. The findings indicate that the DL of the APC service industry and APC efficiency in the less-developed regions of the West have a positive driving effect on each other. However, the magnitude of this effect was asymmetric and transient. The APC service industry’s DL and APC efficiency are more dependent on their inertia, and no efficient two-way feedback mechanism has been formed. This study provides a reference for the construction and sustainable development of modernized APC systems in less-developed regions.