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Global food security is being threatened by the reduction of high‐quality cropland, extreme weather events, and the uncertainty of food supply chains. The globalization of agricultural trade has elevated the diversification of non‐grain production (NGP) on cultivated land to a prominent strategy for poverty alleviation in numerous developing nations. Its rapid expansion has engendered a multitude of deleterious consequences on both food security and ecological stability. NGP in China is becoming very common in the process of rapid urbanization, threatening national food security. To better understand the causal mechanisms and enable governments to balance food security and rural development, it is crucial to have a clear understanding of the spatiotemporal dynamics of NGP using remote sensing. Yet knowledge gaps remain concerning how to use remote sensing to track human‐dominated or ‐induced long‐term cultivated land changes. Our study proposed a method for detecting the spatiotemporal evolution of NGP based on Landsat time‐series data under the Google Earth Engine platform. This approach was proposed by (1) obtaining the union of cultivated lands from multiple landcover products to minimize the cultivated land omission, (2) constructing multi‐index dynamic trend rules for 3 representative types of NGP and obtaining results at the pixel level, while adopting the continuous change detection and classification algorithm to Landsat time series (1986–2022) to determine when the most recent change occurred, (3) minimizing the noise by object‐oriented land use–land cover classification and mode filter approaches, and (4) mapping the spatiotemporal distribution of NGP. The proposed methodology was tested in Jiashan, located in Zhejiang Province (eastern China), where NGP is widespread. We achieved a high overall accuracy of 95.67% for NGP type detection and an overall accuracy of 85.26% for change detection of time. The results indicated a continued increasing pattern of NGP in Jiashan from 1986 to 2022, with the cumulative percentage of NGP increasing from 0.02% to 20.69%. This study highlights the utilization of time‐series data to document essential NGP information for evaluating food security in China and the method is well‐suited for large‐scale mapping due to its automatic manner. [ABSTRACT FROM AUTHOR]

The reservoir in the Anyue gas field, located in the Sichuan basin of China, belongs to the second member of the Dengying formation and has distinctive geological features. It is characterized by strong heterogeneity, low porosity, low permeability, and locally developed natural fractures. The reservoir space consists primarily of corrosion holes, natural fractures, and similar voids. Moreover, the lower reservoir exhibits high water saturation and a homogeneous bottom-water interface. Since it is a carbonate-based hydrocarbon reservoir with low porosity and permeability, deep acid fracturing has proven to be an efficient method for enhancing individual well production. However, the reconstruction of the second member of the Dengying formation reservoir poses significant challenges. The reservoir contains high-angle natural fractures, small vertical stress differences, and is located in close proximity to the gas–water interface. As a result, it becomes difficult to control the height of the acid break. Improper acid break treatment may easily result in water production affecting gas well production. To explore ways to control the longitudinal extension of acid fractures, 3D numerical models focusing on the initiation and expansion of acid fractures have been developed. This model takes into account geological and engineering factors such as stress differences, acid fracture displacements and scales, and their effects on the longitudinal extension of acid fractures. It was revealed that the pressure difference is the main controlling factor for the acid fracture height, followed by the reservoir thickness, the interlayer thickness, and the viscosity of the working fluid. Technical countermeasures for controlled fracture and high-acid fracturing tailored to different reservoir characteristics have been proposed, and design parameters for controlled fracture and high-acid fracturing can be optimized. By effectively controlling the vertical extension of the acid fracture, it is possible to maximize production from a single well while avoiding interference from the lower water layer. This study provides theoretical guidance for the application of deep-acid-fracturing techniques in low-permeability bottom-water gas reservoirs. [ABSTRACT FROM AUTHOR]

Bitespiramycin, has been shown to have a therapeutic effect against respiratory tract inflammation, including a potential effect against COVID-19. A current clinical trial in China showed that bitespiramycin was an effective treatment for severe pneumonia and intracranial infection. However, there is lack of an analytical method to elucidate the distribution of bitespiramycin. In this study, a highly sensitive, rapid and reliable UPLC–MS/MS method was developed to comprehensively characterize the bitespiramycin distribution in various bio-samples, which is significantly improved upon the published work. A rapid sample preparation method was developed by using n-butanol as the solvent to extract bitespiramycin from different bio-samples. The extract was then directly analyzed by UPLC–MS/MS coupled with an alkaline-resistant column after centrifugation which avoids the time-consuming concentration process under nitrogen and redissolution. The method was employed to accurately quantify bitespiramycin and its metabolites in rat plasma, tissues, and human cerebrospinal fluid. Notably, the presence of bitespiramycin and its metabolites was identified for the first time in various rat organs including brain, testis, bladder and prostate as well as in human cerebrospinal fluid. This newly developed approach shows great promise for drug distribution assays including other antibiotics and can help elucidate the ADME of bitespiramycin. [ABSTRACT FROM AUTHOR]

Incorporating three-dimensional (3D) spatial measurement into the urban expansion measurement system plays an important role in understanding the degree of urban expansion and regulating and governing it. This article proposes an urban concrete forest and constructs an Urban Volume Sprawl Index to quantitatively study the spatiotemporal characteristics of the three-dimensional expansion of Chinese prefecture-level cities. Furthermore, geographic detectors are used to study its influencing factors. The following conclusions are drawn: (1) Between 1990 and 2018, the volume of Chinese cities has increased from 414.67 to 1,406.29 km3, with a growth rate of 239.13%. (2) The overall growth rate of urban volume shows a gradual slowing trend during the research period, from 55.99% to 40.83%. (3) Between 1990 and 2018, the Urban Volume Sprawl Index nationwide gradually slowed down (from 5.18% to 3.90%), with the largest rate reported in the western region (4.1%), the middle in the eastern region (3.46%), and the smallest in the central region (3.28%). (4) Government and economic factors have the greatest impact on the three-dimensional expansion of Chinese cities (over 69%), with social factors in the middle, and natural factors having the weakest explanatory power (less than 15%). (5) There are differences in the degree of urban expansion between two-dimensional and three-dimensional perspectives. A total of 38.1% of cities have a greater degree of urban expansion from a two-dimensional (2D) analysis perspective, which are mainly small cities located in the western and eastern regions. A total of 5.4% of cities (mainly located in the Yangtze River Delta and Pearl River Delta regions) have a greater degree of urban expansion from a 3D perspective. The remaining cities (56.5%) go through the same level of urban expansion in both analysis dimensions. A 3D urban expansion analysis can better explain and reveal the actual production and living space provided by urban expansion than 2D analysis. It can provide temporal data for urban land efficiency evaluation, ghost city identification, etc., and it has good application and promotion prospects. [ABSTRACT FROM AUTHOR]

Many coal mining areas overlapped with agricultural land in the world. However, surface subsidence and waterlogging brought on by coal mining inexorably harm the agricultural land. Soil moisture can reflect the variation of mining impact significantly according to the geographic features of the high underground water table, which shows significant spatial gradient variation within the subsidence basin. Previous studies have used site survey and unmanned aerial vehicle (UAV), which are not applicable to large‐scale assessments of the ecological impacts and defining the scale of impacts. Here, we used the Google Earth Engine (GEE) platform and an optical trapezoid model (OPTRAM) to estimate the soil moisture distribution around 50 mining subsidence waterbody samples in eastern China. Based on the spatial variation in soil moisture, the impact boundary of coal mining was determined using buffer analysis and trend fitting. The results showed that: (1) The OPTRAM can well reflect the soil moisture distribution which shows a good correlation between estimated and measured values, with R = 0.83 and RMSE = 0.054. (2) The spatial trend fitting of soil moisture is suitable for evaluating mining impact, and the impact distances are in the range of 96–762 m, 80% of which are located at 128–436 m. We also find that 28% of subsidence waterbody buffer basins were heavily influenced by human activities, and the coal mining impact boundaries cannot be effectively identified. The study provides a new idea to quantify the ecological and agricultural impact boundary of coal mining, which could be applied to other similar regions across the globe. [ABSTRACT FROM AUTHOR]

Background: Increasing evidence show that women across the world face unacceptable mistreatment during childbirth. Person-centered maternity care is fundamental and essential to quality of healthcare services. The aim of this study was to translate and determine the psychometric properties of the Person-Centered Maternity Care (PCMC) Scale among Chinese postpartum women. Methods: A cross-sectional study was conducted among 1235 post-partum women in China. The cross-cultural adaptation process followed the Beaton intercultural debugging guidelines. A total of 1235 women were included to establish the psychometric properties of the PCMC. A demographic characteristics form and the PCMC were used for data collection. The psychometric properties of the PCMC were evaluated by examining item analysis, exploratory factor analysis, known-groups discriminant validity, and internal consistency. Results: The number of extracted common factors was limited to three (dignity & respect, communication & autonomy, supportive care), explaining a total variance of 40.8%. Regarding internal consistency, the Cronbach's alpha coefficient and split-half reliability of the full PCMC score were 0.989 and 0.852, respectively. Conclusions: The Chinese version of the PCMC is a reliable and valid tool to assess person-centered care during childbirth in China. [ABSTRACT FROM AUTHOR]

Drug-induced liver injury (DILI) is a type of bizarre adverse drug reaction (ADR) damaging liver (L-ADR) which may lead to substantial hospitalizations and mortality. Due to the general low incidence, detection of L-ADR remains an unsolved public health challenge. Therefore, we used the data of 6.673 million of ADR reports from January 1st, 2012 to December 31st, 2016 in China National ADR Monitoring System to establish a new database of L-ADR reports for future investigation. Results showed that totally 114,357 ADR reports were retrieved by keywords searching of liver-related injuries from the original heterogeneous system. By cleaning and standardizing the data fields by the dictionary of synonyms and English translation, we resulted 94,593 ADR records reported to liver injury and then created a new database ready for computer mining. The reporting status of L-ADR showed a persistent 1.62-fold change over the past five years. The national population-adjusted reporting numbers of L-ADR manifested an upward trend with age increasing and more evident in men. The annual reporting rate of L-ADR in age group over 80 years old strikingly exceeded the annual DILI incidence rate in general population, despite known underreporting situation in spontaneous ADR reporting system. The percentage of herbal and traditional medicines (H/TM) L-ADR reports in the whole number was 4.5%, while 80.60% of the H/TM reports were new findings. There was great geographical disparity of reported agents, i. e. more cardiovascular and antineoplastic agents were reported in higher socio-demographic index (SDI) regions and more antimicrobials, especially antitubercular agents, were reported in lower SDI regions. In conclusion, this study presented a large-scale, unbiased, unified, and computer-minable L-ADR database for further investigation. Age-, sex- and SDI-related risks of L-ADR incidence warrant to emphasize the precise pharmacovigilance policies within China or other regions in the world. This study provides a whole epidemiological picture of L-ADR in mainland China, and concluded that L-ADR has a persistent increase. This work provides a powerful tool to mine the potential hepatotoxic drugs in the future. [Display omitted] [ABSTRACT FROM AUTHOR]

In the oil and gas industry, traditional logging mostly deems that oil and gas reservoirs are characterized by high resistivity, whereas the water layer is often by low resistivity. However, a lot of exploration and development practices on shale gas reservoirs in Sichuan Basin, China, prove that it is hard to characterize a functional relation between resistivity and water saturation using the Archie equation. Therefore, to make clear the mechanism to form low resistivity in shale gas reservoirs, the matrix resistivity was calculated through the percolation network simulation based on pore structure characteristics and mineral compositional parameters. Moreover, the resistivity in low-resistivity laminations of shale was measured through the finite element simulation. In addition, the reasons for such low resistivity in shale were analyzed according to the resistivity-forming mechanism, and the effects of penetration degree, width, quantity, and spatial distribution of the laminations on the resistivity were worked out. Those may provide theoretical support for explaining the phenomenon of low-resistivity gas reservoirs. [ABSTRACT FROM AUTHOR]

Rock resistivity is a major geophysical technical parameter in geological and geotechnical engineering, geothermal prospecting, and oil and gas exploration. Its accurate measurement is of great significance to achieve the goal of "carbon peak and carbon neutrality". To solve anisotropic problems, a method to test the radial resistivity in cylindrical core samples has been proposed and has been deemed the universal method, as it has the virtues of no specially processed sample being needed and nondestructive testing. However, there is still a difference in the radial resistivities obtained from this method and another testing method that is commonly used for cuboid samples. Furthermore, the differences between these methods have not yet been made clear in China or elsewhere. Therefore, we compared the results of the above-two testing methods via numerical simulations after establishing the potential field distribution, and, in combination with their methodological principles, illustrated the differences between the resistivities determined in samples with distinct shapes obtained using the two testing methods, summarized the conditions when there was zero difference and considerable difference when using the two methods, and provided a theoretical basis for the reasonable selection of an appropriate method to test the resistivity anisotropy. [ABSTRACT FROM AUTHOR]

Farmland consolidation (FC) is among the measures to solve farmland issues, such as farmland fragmentation, and its impact on the ecological environment has always been controversial. In terms of long-term series and large-area analysis, the calculation of a large amount of data makes the analysis of the ecological–environmental quality of farmland consolidation very difficult. To solve this problem, our study applied a remote sensing ecological index model on the Google Earth Engine platform to analyze the changes in the ecological–environmental quality in two prefecture-level cities in Liaoning Province over the past 20 years. In addition, we analyzed the impacts of FC projects on the ecological environment from 2006 to 2018 and compared them to farmland without consolidation. The study results show that FC caused negative impacts on the quality of the ecological environment during the FC period (2006–2018) and that the FC's positive effects take time to develop. In each FC phase, the results showed that FC exhibited negative effects before 2010 because the proportion of ecological–environmental quality reductions (0–47.67%) was higher than the proportion of increases (9.62–46.15%) in those FC phases. Since 2011, the area experiencing positive ecological–environmental benefits (31.96–72.01%) enabled by FC is higher than the area of negative impact (2.24–18.07%). This seems to be triggered by policy evolution. Based on the trend analysis, the proportion of FC areas with improved ecological–environmental quality grew faster (Gini index decreased 0.09) than that of farmland without consolidation (Gini index decreased 0.05) from before FC to after FC. Moreover, the new FC projects (2011–2018) performed better than the early projects (2006–2010), which may be due to policy evolution and technological advancements. However, the new FC projects (2011–2018) caused a dramatic decrease in ecological–environmental quality in a small number of areas due to the study time constraints. In conclusion, we believe that FC could improve the ecological–environmental quality of farmland, whereas some measures are needed to reduce its temporal negative impact on ecological–environmental quality, which may be caused by human interference. The remote sensing ecological index obtained using the Google Earth Engine platform provided an effective and reliable method for detecting the impacts of FC on the ecological–environmental quality of farmland. This could provide the basis and support for the monitoring of ecological–environmental changes in FC areas at a regional level. [ABSTRACT FROM AUTHOR]

• We simulate future urban 3D expansion in China from 2010 to 2100. • Our projections encompass 5 Shared Socio-economic Pathways. • Future changes include both horizontal expansion and building height information. • China's building volume is projected to increase to 4500–6500 km3 by 2050. • Building volume demand in 2100 will decline to 60% of the demand in 2050. The 21st century is marked by urbanization, with global focus on horizontal city expansion. Yet, vertical growth lacks research due to data scarcity. This study investigates the fusion of urban building height predictions with conventional sprawl projections to offer a holistic 3D urban expansion foresight. We constructed a model for projecting urban building volume using socio-economic factors includes GDP, population, and urbanization indicators, enabling the anticipation of China's 2010–2100 building volume demand across five Shared Socioeconomic Pathways (SSPs). Furthermore, deep learning-based neural networks were harnessed for estimating land conversion probabilities and building heights. By aggregating the projected demand, we estimated spatial expansion and building heights for each scenario at ten-year intervals from 2010 to 2100. Compared to other products, our proposed method excels in spatial granularity and temporal continuity, which includes height properties in the 3D structure. According to the projections of this study, considering various SSPs, China's building volume is expected to reach approximately 4500 km3 to 6500 km3 by 2050, representing 1.3–1.9 times increase compared to 2010. Furthermore, forecasts for 2050–2100 anticipate a notable decline to 60 % of the 2050 demand. At a more local level, potential spatial imbalances may arise, as the projections indicate significant urban expansion in the eastern areas and a heightened density of urban land within existing city clusters. This approach surpasses the constraints of 2D analysis, pioneering the prediction of fine-resolution, long-term spatiotemporal urban expansion in China (2010–2100), contributing a model and data support for future sustainable urban development pursuits. [ABSTRACT FROM AUTHOR]

Aimin Luo,3 Shunkai Lai,1 Tingting He,4 Yuchong Luo,2 Ying Wang,5 Yiliang Zhang,1 Shiyi Shen,4 Hui Huang,4 Shenglin Wen,2 Yanbin Jia11Department of Psychiatry, First Affiliated Hospital, Jinan University, Guangzhou, Guangdong Province, People's Republic of China; 2Department of Psychiatry, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong Province, People's Republic of China; 3Department of Psychology, Guangdong Sanjiu Brain Hospital, Guangzhou, Guangdong Province, People's Republic of China; 4School of Management, Jinan University, Guangzhou, Guangdong Province, People's Republic of China; 5Medical Imaging Center, First Affiliated Hospital, Jinan University, Guangzhou, Guangdong Province, People's Republic of China*These authors contributed equally to this workCorrespondence: Yanbin JiaDepartment of Psychiatry, First Affiliated Hospital, Jinan University, Guangzhou, People's Republic of ChinaTel +86 13392489168Fax +86 020-38688888Email [email protected] Purpose: This study aimed to investigate the mechanism of working memory (WM) impairment in drug-naive obsessive-compulsive disorder (OCD) by using neuropsychological tests and proton magnetic resonance spectroscopy (1H-MRS). Patients and Methods: A total of 55 patients with drug-naive OCD and 55 healthy controls (HCs) were recruited for this study. The working memory (WM) was evaluated using the digit span test (DST), visual space memory test (VSMT), and the 2-back task and stroop color word test (SCWT). The bilateral metabolite levels of the prefrontal cortex (PFC) were evaluated by 1H-MRS, then determined the ratios of N-acetyl aspartate (NAA), choline-containing compounds (Cho), and myo-inositol (MI) to creatine (Cr). The independent sample t-test was used to analyse the differences in WM performance and neurometabolite ratios. Multivariate linear regression analysis was performed to screen the influential factors of WM, with an introduction level of 0.05 and a rejection level of 0.10. Results: 1) Patients with OCD performed significantly worse on DST (score), VSMT (score), 2-back task (accuracy rate), SCWT (execution time) when compared with HCs. 2) NAA/Cr and Cho/Cr in the left PFC (lPFC) and MI/Cr ratios in the bilateral PFC of OCD patients were significantly lower when compared to HCs. 3) For OCD patients, the NAA/Cr ratio in the lPFC was negatively correlated with the score of DST (forwards), the Cho/Cr ratio in the lPFC was positively correlated with the accuracy rate of 2-back task, and the MI/Cr ratio in the right PFC (rPFC) was positively correlated with the score of DST (forwards) and the accuracy rate of VSMT. We also found that the compulsive symptoms showed a positive correlation with MI/Cr ratio of the rPFC. Conclusion: Drug-naive OCD patients have demonstrated WM impairments, including phonological loop, visual-spatial sketchpad and central executive system, and the WM impairments might be associated with hypometabolism in the PFC, especially the lPFC. [ABSTRACT FROM AUTHOR]

Surface mining has been subject to increased criticism and pressure due to its potential to cause environmental damage. China accounts for more than half of world coal consumption, and this continued demand for coal, combined with low costs, has accelerated surface coal mining worldwide. However, it isn't easy to understand the impact of surface mining in China. Therefore, combined with POI, the Exposed Coal Frequency Index (ECFI) was constructed without any mining information in China. A LandTrendr algorithm was used to identify past mining disturbances and reclamation events (1986–2021). While examining these events, surface destruction due to coal mining in China was revealed. Based on the results, (1) the detection accuracy of statistical surface mining sites by province reaches 91.8%, while the detection accuracy of disturbance and reclamation events exceeds 72.59 %. Also, by comparing the mine data, our results provide more accurate information regarding both time and spatial consistency. (2) 253.61 km2 of surface mining sites were identified in 14 provinces or autonomous regions during 1986–2021. Of these, Inner Mongolia, Ningxia, Shanxi and Xinjiang ranked in the top four occupying 89.0% of the total mining site. (3) China has cumulatively disturbed 545.84 km2 and reclaimed 169.41 km2 including more comprehensive human activities. In the last 12 years, large-scale mining and reclamation have accounted for 51.63% and 75.17% of the cumulative area, respectively. (4) Generally, reclamation in China can be completed within four years. In contrast, reclamation time intervals and the proportion of reclamation varied widely between mining areas. Clearly, this study provides the most accurate data on surface coal mining disturbances in China, which will be beneficial for future studies in spatial geography related to mining. It also includes more policies and management creation for mines. [Display omitted] [ABSTRACT FROM AUTHOR]

In recent decades, cropland policies have been recognized as crucial tools for ensuring food security and managing urban growth. However, whether cropland conservation undermines urban land use efficiency (ULUE) in peri-urban areas has not been adequately studied. This study investigated the impact of cropland on ULUE in the peri-urban areas of 36 rapidly urbanizing metropolitan areas in China. Multiple open-source datasets were used, including land use, land cover, three-dimensional building structure, and nighttime light (NTL) data. Urban construction land patterns (infilling, edge, outlying) were categorized to examine the intermediate role of urban form in the correlation between cropland and ULUE. The findings indicated that: (1) high proportion of cropland area within the peri-urban areas significantly undermined ULUE; (2) although the conservation of cropland is conducive to compact urban growth, the infilling expansion pattern that compelled by cropland conservation would not sustain intensive human activity; and (3) reducing the spatial separation between conserved cropland and urban construction land was conducive to the dual objectives of protecting cropland and promoting ULUE. This study contributed to the development of a nuanced understanding of cropland protection policies that balance national food security and urbanization efficiency. • High percentage of cropland in peri-urban area threatens urban land use efficiency (ULUE). • Intensive cropland occupation tends to drive compact urban growth. • Compact urban expansion compelled by cropland conservation does not present high ULUE. • Cropland significantly undermines the ULUE of infilling expansion patterns. • A balanced policy approach for cropland conservation and urbanization is advisable. [ABSTRACT FROM AUTHOR]

With the steady growth of the economy and the rapid development of modern industrial technology, the problem of environmental pollution has increased. To continue to develop, it is necessary to thoroughly implement the sustainable development strategy, and we must pay more attention to environmental issues. One of the important management tools implemented in China for environmental management is environmental quality monitoring and evaluation. Environmental quality monitoring can scientifically evaluate the environmental quality of a region, scientifically evaluate and forecast the environmental management and environmental engineering, and provide scientific basis for environmental management, environmental engineering, formulation of environmental standards, environmental planning, comprehensive prevention and control of environmental pollution, and ecological environment construction. This paper will discuss the basic principles of neural network and the implementation process of MATLAB and in the MATLAB software implementation and display process. At the same time, the results of different parameters are analyzed through experiments, and the network parameters are constantly adjusted to improve the accuracy of the evaluation results. Taking the regional environment as an example, two monitoring methods are proposed, and a variety of neural network models are used to analyze each prediction method. Case study results show that the latter method has a better prediction effect. [ABSTRACT FROM AUTHOR]

Abstract China's environmental problems are not only related to the fundamental interests of the broad masses of the people, but also to China's national security and international image. At present, China's environmental protection work is facing a complex situation. Pollution sources can be divided into natural pollution sources and man-made pollution sources. Natural sources of pollution refer to places where nature releases harmful substances or causes harmful effects to the environment, such as active volcanoes. Man-made pollution source refers to the pollution source formed by human activities, and is also the main object of environmental protection research and control. Among the man-made pollution sources, air pollution sources, water pollution sources and soil pollution sources can be classified according to the main objects of pollution. Among them, air pollution sources and water pollution sources have the greatest impact on human life. Therefore, it has become an important subject worthy of in-depth discussion to take automatic and electronic measures for potential environmental pollution incidents, discover environmental pollution problems in time, reduce the probability of environmental pollution incidents, and even put some major environmental pollution incidents in their infancy. In this paper, deep learning method is used to classify the existing key pollution source video. Water pollution experiments show that the accuracy of video counting reaches 93.1%, which is better than other video processing schemes. The operation time of the system reaches acceptable range, and a solution to meet the real-time requirement is put forward. [ABSTRACT FROM AUTHOR]

Rapid urbanization and industrialization have largely promoted the transformation of urban and rural space. In recent years, rural residential land expansion (RRLE) has also become a significant problem for the progress of China's rapid urbanization. The phenomenon of RRLE and its impact on cultivated land needs to be taken seriously. From a process perspective, this study aimed to explore the spatiotemporal dynamics of RRLE under conditions of rapid urbanization and reveal its impacts on cultivated land. We analyzed the spatial pattern of cultivated land occupied by rural residential land and discuss the distribution characteristics under different factors. Our results show that: (1) the changing trend in RRLE between 1990 and 2020 ran counter to that of rural population. The problem of "decreasing population vs. increasing rural residential land" in rural China is significant. The spatial distribution of RRLE was dense in the east of the country and sparse in the west. Landscape metrics indicated that rural settlements still show irregular development; (2) the impacts of RRLE on the cultivated land system were significant. In general, these impacts were greater than those of urban expansion, and showed significant regional differences; (3) the cultivated land occupied by rural residential land was distributed mainly in city suburbs and areas of low elevation and slope, and were closely related to the direction of traffic flow. Based on these findings, some suggestions for optimizing the interrelations between population and rural residential land are proposed. • Identify the spatial and temporal patterns of rural residential land expansion in China. • Rural residential land expansion has caused massive loss of rich cultivated land. • Spatial inequalities in rural residential land expansion and its impacts on cultivated land is significant. • Propose regulation suggestions of different geographical regions. [ABSTRACT FROM AUTHOR]

Mass mortality of juvenile hybrid (Haliotis discus hannai ♀× H. fulgens ♂, DF) and adult H. discus hannai (DD) occurs in south China during the summer. This study showed that the juvenile DF and adult DD exhibited significantly lower survival rates than juvenile DD and adult DF under 72 h pathogenic bacteria (Vibrio harveyi) challenge at different temperatures (20 °C and 28 °C). Phenoloxidase (PO) and superoxide dismutase (SOD) activities were significantly higher in juvenile DD compared to juvenile DF, whereas that in adult abalone was the opposite. Juvenile DD and adult DF also exhibited advantages in terms of immune-related gene expression (TRAF , TLR , MIF , Lys , Spi , Cat , TNF , and SOD) compared to juvenile DF and adult DD. The data reveals immunocompetence differences in DD and DF at the juvenile and adult stages. • Juvenile hybrid (DF) and adult Pacific abalone (DD) were weaker than juvenile DD and adult DF under bacteria challenge. • PO and SOD activities were significantly higher in juvenile DD and adult DF. • Juvenile DD and adult DF exhibited advantages in terms of immune-related genes' expression. [ABSTRACT FROM AUTHOR]

• A new index was proposed to monitor surface mining disturbance. • The new index enhance the sensitivity to improve the detection accuracy. • Compared with five products, the detection accuracy is superior. • Mine Landscape Damage/Reclamation Index can be widely used in the detection of open-pit mining. The exploitation and utilization of mineral resources have significantly contributed to economic and social development; however, the procession has also negatively impacted the ecological environment. Thus, it is necessary to effectively monitor coalfields, an important basis for reasonable development and utilization of coalfields and following ecological reclamation. Based on MODIS Global Damage Index, We couple the Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI), and proposal the Mine Landscape Damage Index (MLDI) and Mine Landscape Reclamation Index (MLRI) to supervise the disturbed vegetation of mines. Huolinhe coalfield, one of the largest mines in China, is monitored in this research. 3675 Landsat imageries from 1990 to 2020 are analyzed using the LandTrendr algorithm with MLDI and MLRI time series data on Google Earth Engine. The results demonstrate that this method could distinguish the region and disturbing process of damage and reclamation due to its effectiveness proved by visual interpretation of high-resolution imageries and verification of field investigation. The total detected area of vegetation damage was 16505.10 ha, and the vegetation damage in the mining was active from 2006 to 2011, with average annual damage of more than 1000 ha. The total area of vegetation restoration in the mine is 8640.81 ha, accounting for 52.35% of the vegetation damage. Vegetation restoration has increased gradually since 2010. In the past three years, vegetation restoration accounted for 47.61% of the total reclamation area. A novel index for monitoring the effects of surface damage in multi-open-pit mining areas is provided to us, and the detection is reliable. It can give the government an effective practical data reference in the sustainable development of utilization management and ecological reclamation in coalfield. [ABSTRACT FROM AUTHOR]

• A novel approach is applied to measure the land-use efficiency of resource-based cities. • Applied the ternary phase diagram to identify critical factors in the three criteria. • Significant differences in the land-use efficiency of resource-based cities in growth stages. China is accelerating the transformation and development of resource-based cities. Urban land-use efficiency is crucial for assessing land output capacity and regional development quality. Measuring the land-use efficiency of resource-based cities and determining its main factors help improve land-use efficiency and promote the transformation of resource-based cities. However, previous urban land-use efficiency studies of multi-source data and its driving factors have been insufficient. Therefore, according to this study's inherent characteristics of urban land use efficiency, a feasible analysis framework is built using multi-source remote sensing data. Three indicators are proposed: urban construction land intensity, urban nighttime light intensity, and urban point of interest (POI) density. We developed the urban land-use efficiency index (ULEI) to explore the spatial pattern of urban land-use efficiency in resource-based cities. We applied the ternary phase diagram to identify critical factors in the three criteria. The results show that land-use efficiency is generally low in resource-based cities at the county scale. According to the ULEI, the top and bottom resource-based cities have significant agglomeration. The southwest region has higher land-use efficiency, while the northern region has the opposite. Meanwhile, there are significant differences in the urban land-use efficiency of resource-based cities in different growth stages. Growing cities have the highest land-use efficiency, while recessionary cities have the opposite. In addition, resource-based cities with higher land-use efficiency tend to be more balanced among the three criteria. Our results show the approach's effectiveness, which provides objective and precise spatial information for urban land use at the county scale for resource-based cities, leading to more informed decision-making. [ABSTRACT FROM AUTHOR]

Land use efficiency (LUE) is considered a significant yardstick for guiding the practice toward sustainable urban development for metropolitan areas. However, existing evaluation methods on LUE ignore the urban function carrying capacity of the urban construction land. This study proposes a theoretical approach for measuring LUE from a vacancy-and-utilization perspective. Accordingly, the land use efficiency index (LUEI) measurement is built up by incorporating nighttime light intensity, population density, and facility density of built-up land. Furthermore, the spatial pattern of the peri-urban areas' LUEI of 36 metropolitan areas in China is investigated. There are three significant findings. First, the LUEIs of the peri-urban area in eastern and western areas are 0.102 and 0.116, respectively, which are almost twice higher than that of the central area, which is only 0.067. Second, the balance between the contributions of LUEI's indicators is conducive to promoting LUE, indicating a bucket effect for achieving high LUE. Third, the average LUEI of county units with fewer facilities is 1.27 and 2.65 times lower than county units with less population and human activities. This new method not only provides a practical way to monitor LUE but would also be an essential basis for land use management. • A new method for evaluating land use efficiency (LUE) is proposed. • The new method is proven applicable in 36 metropolitan areas in China. • A buckets effect for LUE indicators exists for achieving high LUE. • An organized urban function spatial layout is conducive to LUE. [ABSTRACT FROM AUTHOR]

Long-term stable cultivated land (LSCL) is associated with food security. However, relevant studies about monitoring the eco-health condition (EHC) change of LSCL are insufficient at the national level. In our study, the Google Earth Engine platform and the remote sensing pixel-based ecological index model (RSEI-2) were employed to detect the EHC change tendency of LSCL from 2001 to 2019 at the national level. The results showed that approximately half of the LSCL EHC is increasing (56.57%) in China. The EHC increase was present in northeastern and southwestern of China. The EHC decrease occurred in northwestern China and the Inner Mongolia area, which have low rainfall. The results of drought division have proven that the limitation of rainfall could increase the risk of EHC degradation on the LSCL. The analysis of field size showed that large field size LSCL plots (16–25 ha) could increase the EHC (approximately 8-fold), while the very large field size LSCL plots (25–100 ha) showed little positive effects (approximately 1-fold). Population urbanization has played a negative role in the sustainability of LSCL. Low urbanization showed a significant positive effect on the EHC of LSCL. To protect LSCL, we propose optimizing farmers' cropping structure and management methods through the incentives and supervision of policy instruments. • A pixel-based model (RSEI-2) is applied on LSCL at the national level. • The half of the LSCLs' EEQ is improving at the national level. • The drought is threatening in EEQ of LSCL. • The EEQ increasing presented in large field size LSCL (16–25 ha). • Population urbanization cause EEQ decreasing of LSCL. [ABSTRACT FROM AUTHOR]

Background: The utilization of soybean heterosis is probably one of the potential approaches in future yield breakthrough as was the situation in rice breeding in China. Cytoplasmic male sterility (CMS) plays an important role in the production of hybrid seeds. However, the molecular mechanism of CMS in soybean remains unclear. Results: The comparative transcriptome analysis between cytoplasmic male sterile line NJCMS1A and its near-isogenic maintainer NJCMS1B in soybean was conducted using Illumina sequencing technology. A total of 88,643 transcripts were produced in Illumina sequencing. Then 56,044 genes were obtained matching soybean reference genome. Three hundred and sixty five differentially expressed genes (DEGs) between NJCMS1A and NJCMS1B were screened by threshold, among which, 339 down-regulated and 26 up-regulated in NJCMS1A compared to in NJCMS1B. Gene Ontology (GO) annotation showed that 242 DEGs were annotated to 19 functional categories. Clusters of Orthologous Groups of proteins (COG) annotation showed that 265 DEGs were classified into 19 categories. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that 46 DEGs were assigned to 33 metabolic pathways. According to functional and metabolic pathway analysis combined with reported literatures, the relations between some key DEGs and the male sterility of NJCMS1A were discussed. qRT-PCR analysis validated that the gene expression pattern in RNA-Seq was reliable. Finally, enzyme activity assay showed that energy supply was decreased in NJCMS1A compared to in NJCMS1B. Conclusions: We concluded that the male sterility of NJCMS1A might be related to the disturbed functions and metabolism pathways of some key DEGs, such as DEGs involved in carbohydrate and energy metabolism, transcription factors, regulation of pollen development, elimination of reactive oxygen species (ROS), cellular signal transduction, and programmed cell death (PCD) etc. Future research will focus on cloning and transgenic function validation of possible candidate genes associated with soybean CMS. [ABSTRACT FROM AUTHOR]

Characteristic towns have emerged along with China's economic and social development. As a new model of small-town development, they have played an essential role in promoting industrial transformation and upgrade, improving the living environment, and promoting regional innovation and development. Accurate identification of the expansion characteristics of National Characteristic Towns (NCTs) is vital for optimizing the spatial layout of characteristic towns and adjusting the policies of characteristic towns. This study used a dataset on nighttime light to identify expanding NCTs and measure their expansion from 2000 to 2020. In total, 233 expanding NCTs were identified, accounting for 58.25% of the NCTs in China. The areas with the most significant intensity of expansion are primarily located in the East, South, and North economic regions. The critical period of NCTs expansion primarily occurred in the periods 2008–2011 and 2011–2014. Our results show that NCTs are highly consistent with the spatial distribution of urban agglomerations, and the development of NCTs is inherently related to the development of urban agglomerations in the region. The implementation of NCT policies has significantly promoted the development of NCTs in the Central and Western economic regions, which face challenging development issues and differ from those in the Eastern region. The method proposed in this study can effectively identify the 'hot spots' of expanding NCTs and the critical periods of their expansion. [ABSTRACT FROM AUTHOR]

• Facility density attenuates follow power-law on the urban center-edge gradients. • Proved that the center-edge gradient is suitable for pattern analysis of polycentric cities. • Density patterns are more consistent among facilities sharing a similar attribute. • Attenuation rates of facility density in polycentric cities are relatively low. • The gradient difference of facility pattern decreases with the growth of urban economy. With the increasing demand for facilities services, revealing the spatial pattern of various facilities with different functions (i.e., functional facility) and the driving role of urban attributes are crucial to improve the spatial equity of facilities, but still little is known. Here, we took 34 cities with different economic levels in China as cases. We assessed the density of nine types of functional facilities along the center-edge gradients, and analyzed the pattern disparity by cluster and correlation analyses. Results showed that facility density on the urban center-edge gradients presented a power-law attenuation, which was fitted for all types of functional facilities, even in the polycentric cities. The consistencies of attenuation rates increased with similarities of functional types of urban facilities, which reflects that the ability to provide facility services is closer. The attenuation rates decreased with the growth of the urban economy and built-up area, indicating the urban-rural dualization of facility distribution has slowed down accordingly. Furthermore, the relatively low attenuation rates of polycentric cities inspire the comprehensive planning based on facility pattern under the condition of limited urban land areas. This research supports improving the well-being of residents' access to various facility services, and further promotes the sustainable development of the cities. [ABSTRACT FROM AUTHOR]

Socioeconomic development is often dependent on the production of mining resources, but both opencast and underground mining harm vegetation and the eco-environment. Under the requirements of the construction for ecological civilization in China, more attention has been paid to the reclamation of mines and mining management. Thus, it is the basement of formulating policies related to mining management and implementing reclamation that detection of mining disturbance rapidly and accurately. This research carries on an empirical study in the Dexing copper mine, Jiangxi, China, aiming at exploring the process of distance and reclamation. Based on the dense time-series stack derived from the Landsat archive on Google Earth Engine (GEE), the disturbance of surface mining in the 1986–2020 period has been detected using the continuous change detection and classification (CCDC) algorithm. The results are that: (1) the overall accuracy of damage and recovery is 92% and 88%, respectively, and the Kappa coefficient is 85% and 84% respectively. This means that we obtained an ideal detection effect; (2) the surface-mining area was increasing from 1986–2020 in the Dexing copper mine, and the accumulation of mining damage is approximately 2865.96 ha with an annual area of 81.88 ha. We also found that the area was fluctuating with the increase. The detected natural restoration was appraised at a total of 544.95 ha in the 1988–2020 period with an average restoration of 16.03 ha. This means that it just restores less in general; (3) it has always been the case that the Dexing mine is damaged by mining and reclamation in the whole year (it is most frequently damaged month is July). All imageries in the mine are detected by the CCDC algorithm, and they are classified as four types by disturbing number in pixel scale (i.e., 0, 1, 2, more than 2 times). Based on that, we found that the only once disturbed pixels account for 64.75% of the whole disturbed pixels, which is the majority in the four classes; (4) this method provides an innovative perspective for obtaining the mining disturbed dynamic information timely and accurately and ensures that the time and number of surface mining disturbed areas are identified accurately. This method is also valuable in other applications including the detection of other similar regions. [ABSTRACT FROM AUTHOR]

In tropical/subtropical monsoon regions, accurate rice mapping is hampered by the following factors: (1) The frequent occurrence of clouds in such areas during the rice-growing season interferes strongly with optical remote sensing observations; (2) The agro-landscape in such regions is fragmented and scattered. Rice maps produced using low spatial resolution data cannot well delineate the detailed distribution of rice, while pixel-based mapping using medium and high resolutions has significant salt-and-pepper noise. (3) The cropping system is complex, and rice has a rotation schedule with other crops. Therefore, the Phenology-, Object- and Double Source-based (PODS) paddy rice mapping algorithm is implemented, which consists of three steps: (1) object extraction from multi-temporal 10-m Sentinel-2 images where the extracted objects (fields) are the basic classification units; (2) specifying the phenological stage of transplanting from Savitzky–Golay filtered enhanced vegetation index (EVI) time series using the PhenoRice algorithm; and (3) the identification of rice objects based on flood signal detection from time-series microwave and optical signals of the Sentinel-1/2. This study evaluated the potential of the combined use of the Sentinel-1/2 mission on paddy rice mapping in monsoon regions with the Hangzhou-Jiaxin-Huzhou (HJH) plain in China as the case study. A cloud computing approach was used to process the available Sentinel-1/2 imagery from 2019 and MODIS images from 2018 to 2020 in the HJH plain on the Google Earth Engine (GEE) platform. An accuracy assessment showed that the resultant object-based paddy rice map has a high accuracy with a producer (user) accuracy of 0.937 (0.926). The resultant 10-m paddy rice map is expected to provide unprecedented detail, spatial distribution, and landscape patterns for paddy rice fields in monsoon regions. [ABSTRACT FROM AUTHOR]

The eastern plain of China is one of the most important grain production areas in China. Meanwhile, the plain is also an important coal production area with a large number of "coal-grain composite regions". Coal mining causes land subsidence and waterlogging, which destroys a significant amount of cultivated land. However, there is no dataset for the spatio-temporal distribution of subsidence water to assist related decision-making on a regional scale. Accurate monitoring of subsidence water is still a challenge, especially distinguishing among subsidence water, natural water and artificially excavated water by only using remote sensing data. Here, A new method to generate a dynamic map for the subsidence ponding year and the restoration year using the Google Earth Engine platform with 33-year-old Landsat imagery was created. The time segmentation method was used to first extract the change water pixels corresponding to subsidence water and artificially excavated water with similar trajectory features. Then, the morphological characteristics of the two types of change water at the beginning year of water accumulation are used to construct 13 landscape indexes. This approach utilizes the Random Forest algorithm to distinguish between subsidence water and artificially excavated water. The Huang-Huai-Hai plain area in eastern China was selected as the study area and extracted the subsidence water areas from 1986 to 2018. The identification accuracies for subsidence ponding year and restoration year are 88% and 85%. 79% of the subsidence water areas are located in cultivated land, which shows significant impacts to agricultural activities. The method proposed could be applied to other similar areas, the results could provide reference and data for decision-making and related land reclamation planning. • A novel methodology was developed for mapping mining subsidence water. • Map of the subsidence ponding year and restoration year. • Random forest algorithm can effectively extract the patch of subsidence water. • Contribute to monitor annual subsidence water at a regional scale. • This paper belongs to change detection using Landsat time series. [ABSTRACT FROM AUTHOR]

Underground coal mining with high groundwater levels causes many environmental problems, one of the main ones being subsidence waterlogging. After the subsidence waterlogging, the land faces many problems, such as insufficient land development and difficult and costly land restoration. Therefore, it is necessary to monitor the spatial range and temporal trajectory pattern of surface subsidence in a timely manner. When information about underground mining is lacking, it is difficult by using remote sensing alone to identify and distinguish (i) natural water, (ii) engineering water, and (iii) subsidence waterlogging. In this study, we used the Google Earth Engine platform to develop a method to detect subsidence waterlogging area and the disturbance year. The method includes pixel-based trajectory extraction and object-based water type recognition. First, LandTrendr is used to extract the change water (engineering water and subsidence waterlogging) pixels and its disturbance year. Then, the morphological method to further eliminate engineering water patches, so as to extract subsidence waterlogging. We selected the Panxie mining area in Huainan, China as the study area. Using 33 years of Landsat time-series data to generate values of the annual water frequency index, maps of the year of water accumulation caused by underground coal mining and the year of restoration during 1989–2016 are drawn with accuracies of 86.5% and 80.7%, respectively. The results show that from 1989 to 2016, the accumulated area of subsidence waterlogging was 7715.25 ha, accounting for 14.5% of the total area of the study area, of which 75.8% occurred from 2008 to 2016. Furthermore, the accumulated area of restoration was 207.18 ha, which occurred after 2007 and accounts for 2.7% of the total area of subsidence waterlogging. Based on the analysis results of the changes of waterlogging types, the best time window for restoration of the waterlogging area is 3y after water accumulation. The main innovation of this paper is to make use of the temporal heterogeneity (Number of year in patches, Y_num) and morphological index (Landscape shape index in patches, LSI) of the change water to distinguish engineering water and subsidence waterlogging. • Map of subsidence waterlogging caused by mining coal using Landsat time-series. • The annual water frequency index is capable to capture the water variability. • A spatial-temporal algorithm identifies the timing of subsidence waterlogging • The algorithm identifies the timing of backfill after subsidence waterlogging. • The algorithm is applicable to other mining areas too. [ABSTRACT FROM AUTHOR]

The development and utilization of mining resources are basic requirements for social and economic development. Both open-pit mining and underground mining have impacts on land, ecology, and the environment. Of these, open-pit mining is considered to have the greatest impact due to the drastic changes wrought on the original landform and the disturbance to vegetation. As awareness of environmental protection has grown, land reclamation has been included in the mining process. In this study, we used the Shengli Coalfield in the eastern steppe region of Inner Mongolia to demonstrate a mining and reclamation monitoring process. We combined the Google Earth Engine platform with time series Landsat images and the LandTrendr algorithm to identify and monitor mining disturbances to grassland and land reclamation in open-pit mining areas of the coalfield between 2003 and 2019. Pixel-based trajectories were used to reconstruct the temporal evolution of vegetation, and sequential Landsat archive data were used to achieve accurate measures of disturbances to vegetation. The results show that: (1) the proposed method can be used to determine the years in which vegetation disturbance and recovery occurred with accuracies of 86.53% and 78.57%, respectively; (2) mining in the Shengli mining area resulted in the conversion of 89.98 km2 of land from grassland, water, etc., to barren earth, and only 23.54 km2 was reclaimed, for a reclamation rate of 26.16%; and (3) the method proposed in this paper can achieve fast, efficient identification of surface mining land disturbances and reclamation, and has the potential to be applied to other similar areas. [ABSTRACT FROM AUTHOR]

Since the reform and opening up, Chinese economic and social development has undergone great changes, and the people's living standards have improved markedly. For the national economy, the engineering construction is not only a carrier for specific economic tasks, but also a driving force for rapid and sustained economic development. With the continuous expansion of the scale of construction projects, safety management problems of construction projects are constantly exposed. How to effectively avoid accidents has become an important issue to be solved urgently in the construction industry. This paper mainly evaluates human factors in the process of construction project management, such as workers' proficiency, workers' safety awareness, technical workers' quality, and workers' emergency capacity, with the purpose of helping China's construction projects proceed smoothly. In this research, we provide a multiple attribute group decision-making (MAGDM) technique based on Pythagorean 2-tuple linguistic numbers (P2TLNs) and the VIseKriterijumska Optimizacija I KOmpromisno Resenje (VIKOR) method for evaluating the human factors of construction projects. P2TLNs are used to represent the performance assessments of decision makers. Relying on a P2TLWA operator, P2TLWG operator, and the essential VIKOR method, a general framework is established. An application is presented to test the validity of the new method, and a comparative analysis with two algorithms and the P2TL-TODIM method is illustrated with detail. [ABSTRACT FROM AUTHOR]

• Multi-source data are integrated to effectively construct RSEI in successive years. • The characteristics of ecological quality variation have been revealed. • The weak positive trend delayed by mining has been proved. • The extent and area of the better or worse trend have been identified. Coal-based industries are critical to the contemporary world's growth, while the environmental degradation associated with the industry is also increasing. In this study, we develop the Remote Sensing Ecological Index (RSEI) and map its distribution from 2000 to 2020 using the Muli coalfield near Qinghai Lake as the research object. This index is obtained by fitting four components that are critically related to the quality of the ecological environment, including greenness, humidity, heat and dryness, to finally obtain a desirable evaluation. The results illustrate that: (1) The RSEI displayed an overall increasing trend on the time scale, but it also went through three lengthier phases of trend changes. In space view, the RSEI of the unaltered areas has greatly improved, while the damaged areas are clearly concentrated in the study area's northwestern region, where mining is common. (2) In the trend test, the overall variation of RSEI was found to be around 3%. RSEI significantly increased in 69.57% of the study region, whereas RSEI decreased dramatically in 30.43% of the study area. (3) In opencast mining disturbed areas and undisturbed areas, a different quality structure can be discovered, with Moderate and Good levels predominating in disturbed areas and Good and Excellent levels predominating in undisturbed areas. The ecological decline in damaged areas significantly hampered the overall upward trend of RSEI. (4) The Globalmoran's I value was 0.558, 0.546, 0.409, 0.574, and 0.680 in 2000, 2005, 2010, 2015, and 2020, respectively, showing a positive association between regional distribution of ecological environment quality and that opencast mining does really degrade that quality. It has been demonstrated that our evaluation accurately classify the local environment as affected by opencast mining, making it crucial for studying the relationship between coal mining and ecological quality. This index can also be utilized in the future when conducting surveys of other regions of intense human disturbance. [ABSTRACT FROM AUTHOR]

The development of coal resources is necessary, but it has a huge negative impact on land, ecology, and the environment. With the increasing awareness of environmental protection and the requirements of related regulations, the design and practice of reclamation projects run through the mining life cycle and continue for a long time after the coal production. High-precision monitoring of mining disturbance and reclamation, quantifying the degree and time of vegetation disturbance and restoration, is of great significance to minimize the environmental effect of mining. Remote sensing, widely used as efficient monitoring tool, but there is not enough research on disturbance and reclamation monitoring taking into account large-scale areas and high temporal and spatial accuracy. Especially when mining sites remain unknown, how to distinguish the disturbance of coal mining and other human activities affecting the surface land cover has become a challenge. Therefore, this paper proposed a method to reconstruct the time series of mining disturbance and reclamation in a large area by using the POI (point of interest) and Landsat time series images using multiple buffer analysis methods. The process includes: (1) Retrieval of POI in the study area based on the public mining list using Python crawler, and buffering 100 km for preliminary extraction of potential mining areas; (2) Using spectral index mask and random forest algorithm to accurately extract the exposed coal on the Google Earth Engine (GEE) platform; (3) Buffering 10 km to identify the occurrence of disturbance and reclamation, using pixel-based temporal trajectory identification of LandTrendr algorithm under GEE. The method successful detect the change points of surface coal mining disturbance and reclamation in eastern Inner Mongolia of China. The results show that: (1) The method can effectively identify the extent of surface coal mining disturbance and reclamation, and the overall extraction accuracy is 81%. (2) Surface coal mining disturbance in eastern Inner Mongolia was concentrated in 2006–2011. By 2020, the total disturbed area is 627.8 km2, with an average annual disturbance of 18.5 km2, and the annual maximum disturbance to the ground reached 64.6 km2 in 2008. With the total reclaimed area being 236.3 km2, the reclamation rate is about 37.6%. This study provides a systematic solution and process for monitoring the disturbance and reclamation of surface coal mining in a large range with little known about the mines' location. It can effectively identify the mining disturbance and reclamation process which can also be extended to other areas, providing a quantitative assessment of mining disturbance and reclamation, which can support further ecological restoration decision-making. [Display omitted] • A remote sensing procedure of surface coal mine classification, disturbance and reclamation monitoring is developed. • Landsat, random forest, web scraping, and Google Earth Engine has been used to detect 73 surface coal mining sites. • 0.94% of the total study area has been disturbed by surface mining. • The developed procedure is able to reveal the surface coal mine reclamation pattern. [ABSTRACT FROM AUTHOR]

• The effect of tide level on a submerged mangrove recognition index (SMRI) was conducted. • The calculated SMRI results from different tidal heights were evaluated. • SMRI can provide great benefits in accurately mapping mangrove forests. Mangrove forests are intertidal wetland with a diverse assemblage of trees, shrubs and palms growing along tropical and subtropical coastlines. Effective mapping of mangrove forests has not yet been achieved due to the periodicity of tidal dynamics. Our previous studies showed that a submerged mangrove recognition index (SMRI), which was proposed based on the differential spectral signature of mangrove forests from high and low tides, has potential advantages in mangrove discrimination and classification. However, the effect of tide level on the performance of SMRI is still unclear. In this study, GaoFen-1 images with various tide heights were acquired, and SMRI images from low tide to high tide were obtained. Then, the resulting SMRI images were compared in detail, and the relationship between tide level and SMRI values was analyzed. This experiment was accomplished via a case study in Yunlin, Guangxi Province in China. The results showed that an increased difference in tide level led to an increase in the number of pixels of high SMRI values, indicating that more undetected submerged mangrove forests could be distinguished using SMRI. Furthermore, an exponential relationship was observed between SMRI and tide level. It suggests that SMRI effectively helps to distinguish submerged mangrove forests from multi-tide remotely-sensed imagery, and also benefits accurate mapping of mangrove forests. [ABSTRACT FROM AUTHOR]

• Constructed a comprehensive evaluation model of urban ventilation potential (UVP) • UVP has a negative correlation with Land Surface Temperature (LST) • Circuit theory is more suitable for the identification of ventilation corridors. • Ventilation corridors have seasonal differences in mitigating LST. In the context of global warming and rapid urbanization, urban wind-heat environment has become increasingly prominent. Although the identification of ventilation corridors has been well investigated, the impact of ventilation corridors on thermal environment remains unclear. Here, we use the single-window algorithm and circuit theory method to analyze the characteristics of land surface temperature (LST) and ventilation corridors in four megacities of China, so as to quantify the effect of ventilation corridors on thermal environment. Results show that circuit theory works well for identifying ventilation corridors. Moreover, we find that spatial distribution of ventilation corridors in one city is remarkably different from another. Interestingly, ventilation corridors, which consist of green spaces, waters, and roads, have a remarkable mitigation effect on thermal environment. LST of each city is mitigated by 2.39 ℃, 3.22 ℃, 2.11 ℃ and 2.60 ℃, respectively, and the cooling intensity in summer is better than that in winter. Thus, it is of great significance to arrange urban form and ventilation corridors to alleviate the impact of high temperature on urban residents. [ABSTRACT FROM AUTHOR]

Grasping cropland abandonment patterns in China can help protect croplands, thereby ensuring the perpetuation of nationwide food security. However, the pattern of long-term cropland abandonment at the national scale remains limited. Here, we investigate the spatiotemporal patterns and drivers of cropland abandonment across China during 1990–2019 by integrating continuous long-term series of land cover, natural factors, and socioeconomic data. We find that the mean abandoned cropland area is 2.34 × 104 km2 per year. The spatial pattern of cropland and natural factors are prime drivers of cropland abandonment, but there is a substantial variation across agricultural regions. Further analysis suggests that annual food loss due to cropland abandonment is about 7.94 billion kilograms, which could feed 19.85 million people. These findings allow for a better understanding of the spatial heterogeneity and driving forces of cropland abandonment patterns, and inspire to govern global cropland abandonment and formulate relevant policies. [Display omitted] • The average annual cropland abandonment in China is 2.34 × 104 km2 (1.21%). • Cropland abandonment is mostly concentrated near the Hu line. • Driving forces vary significantly across agricultural regions. • Food loss is approximately 7.94 billion kilograms per year. • About 7.92 billion kilograms of food will still be lost by 2030. [ABSTRACT FROM AUTHOR]

Highlights • The older person-centered integrated health management model can simultaneously improve multiple health behaviours. • The older person-centered integrated health management model can simultaneously improve multiple health indicators. • The older person-centered integrated health management model can fully mobilize multisectoral involvement and maximize the personalized interaction of experts. Abstract Objective To investigate the effectiveness of the older-centered Integrated Health Management Model Project (OPCHMP) for multiple lifestyle behaviours in the elderly. Methods A 2-arm, parallel, randomized controlled trial was conducted in Nanjing. The elderly were recruited from multiple community health service centres. The intervention group was intervened and received a personalized, 2-year OPCHMP. The control group only received usual care. Adherence to healthy lifestyle behaviours (ATHLBS) is the primary outcome, obtained through a self-reported composite health behaviour score. The secondary outcomes were health indicators. General estimating equation models were performed to analyse longitudinal dichotomous data and continuous data. Results 637 (intervention = 323; control = 314) participants were included in the study. The participants mean age was 70.53 ± 6.07 years. Significant ATHLBS correction was achieved after 24-month follow-up in the intervention group, comparing to controls. And the intervention group reported significantly better health indicators. Conclusion OPCHMP had positive effect on multiple lifestyle habits in elderly population, which is very encouraging. [ABSTRACT FROM AUTHOR]

Objectives The primary objective of the study was to investigate the prevalence and patterns of multimorbidity in the community-dwelling elderly in urban China. Methods By a cluster random sampling method, 2452 persons aged 60 years and older were enrolled as the subjects in an urban community in Nanjing, China. Data on 13 chronic diseases were collected by interviews, physical check-ups and support by physicians. Factor analyses and the logistic regression models were performed to analyze the patterns of multimorbidity. Results The prevalence of multimorbidity was 49.4% in the community-dwelling elderly in urban China. The observed prevalence of 6 chronic disease pairs was higher than their expected prevalence, including hypertension and diabetes, hypertension and coronary heart disease, hypertension and dyslipidaemia, diabetes and cataract, diabetes and hearing disorder, hypertension and stroke. Three patterns were detected as follows: the first pattern with a prevalence of 9.5% covered degenerative diseases (hearing disorder, cataract, joint disease) and cancer; The second pattern with a prevalence of 1.7% was characterized by liver disease, lung disease, gastrointestinal disease; And the third pattern with a prevalence of 22.4% was characterized by cardiovascular diseases (dyslipidaemia, hypertension, coronary heart disease), metabolic diseases (diabetes) and kidney disease. Compared with <70 years, ≥80 years were found as the risk factor of the prevalence of three patterns. Conclusion A significant proportion of elderly populations was affected by multimorbidity in urban China. Specific patterns of multimorbidity were found at group level and the prevalence was associated with age. [ABSTRACT FROM AUTHOR]

The process of urbanization and infrastructure construction has resulted in the occupation and loss of high-quality cropland. Complemented cropland with higher altitudes and slopes from either development or reclamation has become an important component of cropland resources and plays a vital role in ensuring food security. However, existing research mainly focuses on the dynamic balance of quantity, quality, productivity, and impact on the environment, and not enough attention is paid to whether the newly added cropland is efficiently used in the long term. Based on a cropping intensity dataset from 2001–2019, this study applied the sliding window and change detection methods to assess the use continuity and efficiency of complemented cropland from the perspective of cropland abandonment and explored the impact of the abandonment on food production. The results showed the following: (1) The total area of complemented cropland in 2002–2019 reached 279,416.4 km2, accounting for 13.1% of total cropland in the base year (2001). (2) 45.1% of the complemented cropland was abandoned at least once during the past 20 years, making only 65.6% of that land efficiently used, and this percentage was higher in the middle plains and downstream of the Yangtze River. (3) Abandonment had significant impact on the food production of complemented cropland—with a trend of increasing and then decreasing—leading to a food production reduction of 24.3% per year on average, which was more severe in the middle plains and downstream of the Yangtze River. Higher slope and a migrated population promoted the abandonment of complemented cropland. Therefore, the government should strengthen the monitoring of long-term utilization of complemented cropland and strategic reserves to maintain stable utilization. [Display omitted] • The continuity and efficiency of complemented cropland use need to receive additional attention. • Sliding window and change detection were used to extract abandoned complemented cropland. • 45.07% of the complemented cropland was abandoned at least once making that efficiently used only 65.64%. • The abandonment reduced the food production of complemented cropland by 24.27% per year on average. • It is significant for food security to promote effective use of complemented cropland by policy reinforcement. [ABSTRACT FROM AUTHOR]

Abstract: Understanding how to live successfully within our environment is among the most pressing challenges facing contemporary society. This paper probes the problem based on comparative analysis and discusses the relationship between the spatial–temporal distribution of the Neolithic cultural sites and the geographic context in the Hanjiang River Basin in the south of Shaanxi Province, China. Archaeological studies have identified 175 Neolithic cultural sites in the study area, with a sequence of Laoguantai (14C age 8–7 ka BP), Yangshao (14C age 7–5 ka BP) and the late period of the Neolithic Age (14C age 5–4 ka BP). The total number of archaeological sites, the distribution area and the density all showed an early ascending and later descending trend, but the proportion of the number of archaeological sites in the study area to the corresponding value of the entire Shaanxi Province declined sharply. Spatially, these sites were concentrated on the terraces of the Hanjiang River and its main tributaries with an altitude of 400–800 m. Multiple data were integrated to clarify the critical effects of tectonic and geomorphologic conditions on the distribution of the Neolithic sites. Further comparisons revealed the correlation of Holocene climate change and environmental evolution with the Neolithic cultural succession in the study area that ameliorated conditions to generally promote the development of the primitive culture while degeneration coincided with the culture's transition or interruption. The discussion on the origin of the primitive culture and the temporal–spatial distribution corresponding to the regional culture differentiation sheds light on the complex and dynamic human–nature interaction system during the Neolithic Age, thus emphasising the wider field-based investigation and high-resolution reconstruction works of the palaeoclimate and palaeoenvironment in the future. [Copyright &y& Elsevier]

Abstract: Arsenic levels and speciation in the total suspended particles (TSPs) were quantitatively determined by high performance liquid chromatography on-line coupled with hydride generation atomic fluorescence spectrometry in Beijing, China from February 2009 to March 2011. The high TSP levels fluctuated between 0.07 and 0.79mgm−3, with a mean level of 0.32±0.17mgm−3. The total arsenic concentrations ranged from 0.03 to 0.31μgm−3 (mean: 0.13±0.06μgm−3) in Beijing‘s air. The concentrations of As(III) and As(V) ranged from 0.73 to 20ngm−3 (mean: 4.7±3.6ngm−3) and from 14 to 2.5×102 ngm−3 (mean: 67±35ngm−3), respectively. As levels and speciation demonstrated relative higher levels in spring and autumn and lower values in summer and winter. As(V) accounted for 81–99% of the extractable species in the TSP samples which showed that As(V) was the major fraction of the extractable As. Organoarsenic species, monomethylarsonate (MMA) and dimethylarsinate (DMA) were not found in all samples. Higher values of enrichment factors demonstrated that arsenic in TSP mainly come from anthropogenic sources. High As and its species levels in air and respiratory exposure (0.30–0.84μgd−1) attributed to higher excess cancer risk ((4.2±2.0)×10−4) for people in Beijing. [Copyright &y& Elsevier]

Abstract: As one of the important non-grain energy crops, sweet sorghum has attracted the attention of scientific community and decision makers of the world since decades. But insufficient study has been done about the spatial suitability distribution and ethanol potential of sweet sorghum in China. This paper attempts to probe into the spatial distribution and ethanol potential of sweet sorghum in China by ArcGIS methods. Data used for the analysis include the spatial data of climate, soil, topography and land use, and literatures relevant for sweet sorghum studies. The results show that although sweet sorghum can be planted in the majority of lands in China, the suitable unused lands for large-scale planting (unit area not less than 100hm2) are only as much as 78.6×104 hm2; and the productive potentials of ethanol from these lands are 157.1×104–294.6×104 t/year, which can only meet 24.8–46.4% of current demand for E10 (gasoline mixed with 10% ethanol) in China (assumption of the energy efficiency of E10 is equivalent to that of pure petroleum). If all the common grain sorghum at present were replaced by sweet sorghum, the average ethanol yield of 244.0×104 t/year can be added, and thus the productive potentials of sweet sorghum ethanol can satisfy 63.2–84.9% of current demand for E10 of China. In general, Heilongjiang, Jilin, Inner Mongolia and Liaoning rank the highest in productive potentials of sweet sorghum ethanol, followed by Hebei, Shanxi, Sichuan, and some other provinces. It is suggested that these regions should be regarded as the priority development zones for sweet sorghum ethanol in China. [Copyright &y& Elsevier]

Background: The number and proportion of HIV/AIDS patients among older people are continuously and rapidly increasing in China. We conducted a detailed molecular epidemiological analysis of HIV-1 epidemic strains in a developed city in eastern China and found that elderly people play a crucial role in the transmission of subtypes and high pretreatment drug resistance (PDR)., Methods: A total of 1048 samples were obtained from 1129 (92.8%) newly confirmed HIV-1-positive and treatment-naive patients between 2019 and 2023. The 1316 bp target fragment of the pol gene was amplified by reverse transcription polymerase chain reaction (RT‒PCR) and nested PCR, and Maximum-likelihood (ML) phylogenetic trees and molecular transmission network were constructed to analyse the subtypes and transmission clusters. Molecular transmission network was visualized using Cytoscape with the distance threshold of 0.0075. PDR-associated mutations were determined according to the Stanford University HIV Drug Resistance Database., Results: A total of 933 pol sequences (89.0%, 933/1048) were successfully obtained, and twelve HIV-1 subtypes were detected. CRF07&#95;BC was the predominant subtype, accounting for 48.1% (449/933) of sequences, followed by CRF01&#95;AE (29.4%, 274/933). A total of 398 individuals (42.7%, 398/933) formed 89 clusters in the network. Multivariable logistic regression analysis revealed that age, nationality, subtype, and PDR were the most significant factors associated with clustering in the transmission network. The prevalence of PDR was 14.6% (136/933).PDR associated with non-nucleoside reverse transcriptase inhibitors (10.0%, 93/933) was much more common than that associated with nucleoside reverse transcriptase inhibitors (1.8%, 17/933) and protease inhibitors (3.2%, 30/933) (χ 2  = 77.961, p < 0.001). The most frequent NNRTI mutations were K103N/S/KN/NS (52.2%, 71/136), which led to the highest proportion of high-level resistance to nevirapine and efavirenz (52.2%)., Conclusions: Our study revealed the important influence of elderly people on CRF07&#95;BC transmission and the high prevalence of PDR. The clustering of drug-resistant cases was significant, which suggested the potential for localized widespread transmission of drug-resistant strains. HIV screening and the determination of PDR are recommended for older patients to improve early detection and reduce treatment failure and second-generation transmission., (© 2024. The Author(s).)

Background and Aims: Drug-induced liver injury (DILI) is a prevalent adverse reaction in clinical settings. However, there is limited research on age-related differences in DILI. We performed a large-scale retrospective study to delineate the characteristics of DILI across different age groups., Methods: We collected data on a total of 17,946 patients with confirmed DILI hospitalized at the Fifth Medical Center of the People's Liberation Army (PLA) General Hospital in Beijing, China, from January 1, 2002, to December 31, 2022. The patients were stratified based on age into the following groups: children (< 18 years), young adults (18-44 years), middle-aged individuals (45-64 years), and elderly individuals (≥ 65 years). We gathered demographic information, medical histories, laboratory results, disease severity assessments, and mortality statistics for all patients., Results: Overall, the distribution of DILI cases across different age groups was as follows: 6.57% were children, 24.82% were young adults, 49.06% were middle-aged individuals, and 19.54% were elderly individuals. The percentage of females increased with age, rising from 36.47% in the pediatric group to 60.51% in the elderly group. Notably, central nervous system agents (15.44%) and anti-infectious agents (21.80%) were more commonly associated with DILI in children, while cardiovascular agents (10.58%) and herbal dietary supplements or traditional medicines (H/TMs) (26.29%) were more prevalent among elderly people with DILI. Among all age groups, hepatocellular-type DILI was more common in the pediatric group (p < 0.001), whereas cholestatic-type DILI and chronic DILI were more prevalent in the elderly group (p < 0.001). Acute liver failure (ALF) and fatal outcomes were more prevalent in the pediatric and elderly groups, particularly in the pediatric group (2.04%, p = 0.041; 0.85%, p = 0.007, respectively)., Conclusions: Children and elderly individuals face a higher risk of adverse outcomes following DILI., (© 2024. The Author(s).)

Background: Maternal parenting self-efficacy plays a critical role in facilitating positive parenting practices and successful adaption to motherhood. The Perceived Maternal Parenting Self-Efficacy Scale (PMPS-E), as a task-specific measure, confirms its psychometric properties in cultural contexts. Compared with other tools, the advantages of the PMPS-E are as follows: (i) specific context or time period during the lifespan of a child, (ii) explicitly assess parenting self-efficacy across a diverse enough range of parenting tasks or activities during the perinatal/postnatal period and (iii) having robust psychometric properties. The aim of this study was to translate and determine the psychometric properties of the PMPS-E among Chinese postpartum women (C-PMPS-E)., Method: The cross-cultural adaptation process followed Beaton et al.'s intercultural debugging guidelines. A total of 471 women were included to establish the psychometric properties of the C-PMPS-E. Mothers were asked to complete the C-PMPS-E, Edinburgh Postnatal Depression Scale (EPDS), the Generalized Anxiety Disorder-7 (GAD-7) and several demographic questions. The psychometric testing of the C-PMPS-E was established through item analysis, construct validity and internal consistency reliability., Results: Item analysis showed that the critical ratios of all items were greater than 3 between the low-score group and high-score group, and all item-total correlation coefficients were greater than 0.4. The fit indices showed that the original correlated four-factor model of C-PMPS-E was observed to be an excellent fit to the data. The PMPS-E was negatively correlated with the EPDS and GAD-7 demonstrating its discriminant validity. As expected, no significant correlation was found between PMPS-E total or subscale scores and mothers' age. In addition, statistically significant differences for parity were detected for C-PMPS-E total and subscale scores with multipara having higher scores. This was taken as further evidence of the scale known-groups discriminant validity. In terms of internal consistency, the Cronbach's alpha of the C-PMPS-E total scale was 0.950, and subscales ranged from 0.76 to 0.89. Furthermore, a ROC curve analysis was conducted to establish the ability of the C-PMPS-E to distinguish between symptoms of depression and symptoms of anxiety. A cut-off value of 55 was identified that resulted in good specificity and fair sensitivity., Conclusion: The C-PMPS-E is a reliable and valid tool to assess maternal parenting self-efficacy in a Chinese context., (© 2024 John Wiley & Sons Ltd.)

Nitrogen is an essential nutrient and a major limiting element for the ocean ecosystem. Since the preindustrial era, substantial amounts of nitrogen from terrestrial sources have entered the ocean via rivers, groundwater, and atmospheric deposition. China serves as a key hub in the global nitrogen cycle, but the pathways, sources, and potential mitigation strategies for land-ocean nitrogen transport are unclear. By combining the CHANS, WRF-Chem, and WNF models, we estimated that 8 million tonnes (Tg) of nitrogen was transferred into the ocean in 2017 in China, with atmospheric deposition contributing 1/3. About half variation of the offshore chlorophyll concentration was explained by atmospheric deposition. The Bohai Sea was the hot spot of nitrogen input, estimated at 214 kg N ha -1 , while other areas were around 25-51 kg N ha -1 . The largest contributors are agricultural systems (4 Tg, 55%), followed by domestic sewage (2 Tg, 21%). Abatement measures could reduce nitrogen export to the ocean by 43%, and mitigating ammonia and nitrogen oxide emissions accounts for 33% of this reduction, highlighting the importance of addressing air pollution in resolving ocean pollution. The cost-benefit analysis suggests the priority of nitrogen reduction in cropland and transport systems for the ocean environment.

Flooding is one of the most widespread and catastrophic natural disasters. The exposure of cropland to floods is directly related to the quality of cropland and food security, so it is particularly important to map the spatiotemporal evolution of this exposure, with a specific focus on longer time series and higher resolution scales. This study is the first of its kind to analyse the worldwide spatiotemporal variability of Cropland Exposure to Flooding (CEF) with the 30 m resolution of Global Land Analysis & Discovery (GLAD) dataset during 2000-2019. The findings indicate that: (1) the global CEF area increased by a total of 83,429.50 km 2 or 7.75 %, from 2000 to 2019; (2) only North America's CEF showed a downward trend, and the region with the largest increase in CEF was South Asia; (3) the CEF in 23 river basins, including Ganges, Indus, Mississippi, Yangtze, and Danube, accounted for 79.88 % of the global total in 2019P; (4) in 2019P, China had the largest CEF globally, reaching 239,525.07 km 2 . The fastest growing CEF was India, contributing 16.36 % of the global CEF growth. The CEF of United States experienced a reduction trend; (5) two constructed indicators were used in evaluating the CEF of countries worldwide, and a total of 46 countries are considered to be at the highest level of risk, mainly in Europe and Asia. Based on these conclusions, we carried out a cold/hot spot analysis to reveal the spatial heterogeneity and possible driving factors in this phenomenon, and we offer management suggestions to limit the risks to cropland in the floodplains., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Objective: Chronic non-atrophic gastritis (CNAG) is a common clinical gastrointestinal disease with a long and recurrent course. In China, Wuzhuyu decoction (WZYD) has been used for centuries to treat gastrointestinal disorders. To unravel the efficacy and mechanism of WZYD for CNAG, a clinical study was conducted. And metabolomics was used to explore the mechanism of WZYD for CNAG patients., Methods: Twenty patients in total were recruited in this study (Nos. ChiCTR2200062296) and the protocol was approved by the Ethics Committee (Approval number: KY-2022-2-6-1) and complied with the Declaration of Helsinki. The formula granule of WZYD were assessed by UHPLC-QQQ-TOF to discern the main potential active compounds. The endoscopy evaluation and histopathological changes were detected as effective indicators. Serum samples from patients were used for metabolomics. Inflammatory factors in patients' serum were determined by ELISA. Metabolomics revealed a series of differential metabolites and signaling pathways., Results: WZYD was capable to prevent CNAG by ameliorating score of endoscopy evaluation including erosion, hemorrhage, as well as chronic inflammation and active chronic inflammation score after treatment were decreased. The results indicated that 10 core metabolic components were associated with the treatment of WZYD. Moreover, these metabolic components proved that pyrimidine metabolism and thiamine metabolism were critically responsible for CNAG. In addition, WZYD treatment effectively reduced serum levels of TNF-α, IL-10, and COX-2., Conclusion: Altogether, WZYD can effectively alleviate CNAG by inhibiting inflammation and regulating related metabolic processes, which might be the molecular mechanism of WZYD treatment of CNAG. More studies are warranted to be conducted in this area., Trial Registration: ChiCTR, ChiCTR2200062296. Registered 1 August 2022, https://www.chictr.org.cn/com/25/showprojen.aspx?proj=174027., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Hu et al.)

The abandonment phenomenon is familiar in China. It threatens food security and seriously affects the sustainable development of society, the economy, and the natural environment. However, monitoring and mapping abandoned cropland on a large scale remains a challenge because of its complex land-use change process. According to the World Food and Agriculture Organization, cropland not used for agricultural production for more than 5 years is defined as abandoned cropland. This study uses the Landsat high-precision long-time series product to detect cropland nationwide from 1990 to 2019 by using the sliding window method on Google Earth Engine to profile the spatial distribution, intensity, trend, frequency, and recultivation of abandoned cropland. Between 1992 and 2015, the results illustrate that the total area of abandoned cropland in China was 559,170.26 km 2 , 18.59 % of the cropland area. Excluding the recultivated cropland area, China's abandoned cropland area amounted to 392,156.24 km 2 , 13.03 % of the total cropland. Cropland abandonment is mainly distributed in the second terrain gradient in midwestern and southwestern regions such as Inner Mongolia and Gansu. It rarely happens in western and eastern coastal areas. A high abandonment rate area usually has high elevation and slope. The light index is negatively correlated with the abandonment rate in suburban areas. This study is the first to map the spatiotemporal distribution of abandoned cropland in China with high precision at 30 m resolution. It provides an important basis for policies regarding the recultivation of abandoned cropland., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Farmland abandonment, a widespread phenomenon during land-use transition, leads to a cycling or vanishing evolution of farmland resources. As urbanization advances, an increasing number of agricultural laborers migrate from rural to urban areas, causing ongoing farmland abandonment. However, in contrast to the abandoned information extraction and driving mechanisms revelation, the potential risk of farmland abandonment has received insufficient attention. This study took Yangtze River Economic Belt of China as study area, selected multiple aspects to construct a risk assessment system for farmland abandonment, and applied time series change detection to verify the results. The results showed that (1) farmland abandonment risk, with a regional average value of 0.0978, has strong spatial heterogeneity, with high values clustering in Yunnan-Guizhou and Sichuan-Chongqing mountainous areas and low values distributed in the midstream and downstream plains and the Sichuan Basin. (2) The proportion of farmland area gradually decreased as the risk grade increased. Farmland, with low abandonment risk, occupied an area of 204,837 km 2 , constituting the highest percentage of 35.18% among the overall farmland, and was mainly distributed in the provinces of Jiangsu and Anhui. The area of farmland with high risk was 16,458 km 2 , only accounting for 2.83%, the majority of which was clustered in Sichuan and Yunnan provinces. (3) The Normalized Difference Vegetation Index (NDVI) time series change detection validated the reliability of the risk assessment system. Samples of farmland having low abandonment risk indeed had the lowest abandonment rate of 10%, and those which indicated high risk had the highest abandonment rate of 32%. We propose differentiated managements for farmland resources with high and low abandonment risk from the perspective of sustainable use. This study provides a more reasonable and scientific system for farmland abandonment risk assessment and helps to fill the research gap., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)