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The "Yangtze River Economic Belt Development Strategy" is one of China's three major national development strategies. Enhancing the protection and quality of arable land in the Yangtze River Economic Belt (YEB) is pivotal for fostering regional growth. In this study, land use data spanning the years 1980 to 2020 in the YEB were extracted from the national land use database maintained by the Resource and Environment Data Center of the Chinese Academy of Sciences. Employing Geographic Information System (GIS) spatial analysis techniques and arable land change metrics, the study delineated the spatiotemporal characteristics of arable land alterations across the YEB for the period. Additionally, using grain output data at the prefecture level from 2011 to 2020, the paper calculated provincial grain output to analyze the impact of arable land changes over the last four decades on grain output. The findings revealed that: (1) From 1980 to 2020, the total arable land area in the YEB decreased by approximately 41,775 square kilometers, with the most significant decrease occurring in the downstream region. (2) From 1980 to 1990, the primary factor contributing to the decrease in arable land area was the expansion of water bodies, while from 1990 to 2020, the principal reason for the reduction in arable land area was the expansion of construction land. (3) From 1980 to 2020, the decrease in arable land area resulted in a net reduction of approximately 25.12 million tons in total grain output, with the largest decline observed in the downstream regions and the smallest decline in the upstream regions. (4) Consistent with the trends in arable land area reduction, the main reason for the decline in grain output from 1980 to 1990 was the expansion of water bodies encroaching upon arable land, whereas from 2000 to 2010, the primary cause of arable land reduction was the expansion of construction land areas. In conclusion, the research suggested that over the past four decades, the primary driver behind the reduction in arable land within the YEB has been the expansion of construction land areas. Particularly noteworthy was the period from 2000 to 2010, during which the impact of arable land reduction on grain output was most pronounced. This period coincided with the rapid economic development and accelerated urbanization process within the YEB. [ABSTRACT FROM AUTHOR]

The National Key Ecological Function Zones (NKEFZ) serve as crucial ecological security barriers in China, playing a vital role in enhancing ecosystem services. This study employed the theoretical framework of ecological benefits assessment in major ecological engineering projects. The primary focus was on the ecosystem macrostructure, ecosystem quality, and key ecosystem services, enabling quantitative analysis of the spatiotemporal changes in the ecosystem status of the NKEFZ from 2000 to 2019. To achieve this, remote sensing data, meteorological data, and model simulations were employed to investigate five indicators, including land use types, vegetation coverage, net primary productivity of vegetation, soil conservation services, water conservation services, and windbreak and sand fixation services. The analysis incorporated the Theil–Sen Median method to construct an evaluation system for assessing the restoration status of ecosystems, effectively integrating ecosystem quality and ecosystem services indicators. The research findings indicated that land use changes in NKEFZ were primarily characterized by the expansion of unused land and the in of grassland. The overall ecosystem quality of these zones improved, showing a stable and increasing trend. However, there were disparities in the changes related to ecosystem services. Water conservation services exhibited a decreasing trend, while soil conservation and windbreak and sand fixation services showed a steady improvement. The ecosystem of the NKEFZ, in general, displayed a stable and recovering trend. However, significant spatial heterogeneity existed, particularly in the southern region of the Qinghai–Tibet Plateau and at the border areas between western Sichuan and northern Yunnan, where some areas still experienced deteriorating ecosystem conditions. Compared to other functional zones, the trend in the ecosystem of the NKEFZ might not have been the most favorable. Nonetheless, this could be attributed to the fact that most of these areas were situated in environmentally fragile regions, and conservation measures may not have been as effective as in other functional zones. These findings highlighted the considerable challenges ahead in the construction and preservation of the NKEFZ. In future development, the NKEFZ should leverage their unique natural resources to explore distinctive ecological advantages and promote the development of eco-friendly economic industries, such as ecological industry, ecological agriculture, and eco-tourism, transitioning from being reliant on external support to self-sustainability. [ABSTRACT FROM AUTHOR]

As an important vegetation parameter and ecological index, vegetation net primary productivity (NPP) can intuitively reflect changes in the ecological environment and the level of the carbon budget. However, the change trend of NPP and its recovery potential in China over the past 20 years remain unclear. Here, we used trend analysis, multiple regression analysis and residual analysis methods to analyse the change trend in the NPP of China's terrestrial ecosystems from 2000 to 2019, as well as the climax background, restoration status and restoration potential of the NPP of forest, grassland and desert ecosystems. The results showed that (1) the change in vegetation NPP in China from 2000 to 2019 showed a continuous upward trend, with a change slope of 2.39 gC/m2/a2, and the area with a positive slope of change accounted for 68.10% of the country's land area. The contribution rates of meteorological conditions and human activities to vegetation NPP changes were 85.41% and 14.59%, respectively. (2) The results obtained by the regression analysis method of meteorological conditions based on nature reserves could reflect the zonal climax vegetation status to a large extent, and the obtained values had a smooth transition within each ecogeographical division and between each ecogeographical division, which truly reflected the law of gradual change in climate, vegetation and natural conditions. The annual total NPP of the climax background vegetation in China's forest, grassland and desert ecosystems was approximately 2.76 ± 0.28 PgC, and the annual total NPP of the three ecosystems was 1.90 ± 0.2 PgC, 0.80 ± 0.07 PgC and 0.009 ± 0.0005 PgC, respectively. (3) The annual total vegetation NPP of the restoration status of China's forest, grassland and desert ecosystems was 2.24 PgC, and the annual total vegetation NPP of the three was 1.54 PgC, 0.65 PgC and 0.007 PgC, respectively. Benefiting from the effective implementation of climate warming and humidification and ecological engineering, the agro-pastoral zone, the Loess Plateau, the eastern Sichuan Basin and the Greater Khingan Range had the most significant increases in the past 20 years. (4) The annual total vegetation NPP of China's forest, grassland and desert ecosystem restoration potential was approximately 0.52 ± 0.28 PgC, which accounted for approximately 19.05% of the annual total NPP of the climax background vegetation. The annual total vegetation NPP of forest, grassland and desert ecosystems restoration status was 0.36 ± 0.2 PgC, 0.16 ± 0.07 PgC and 0.002 ± 0.0005 PgC, respectively; the restoration potential accounted for 18.80%, 9.67% and 23.95% of the climax background vegetation NPP, respectively. The deployment of ecological projects should fully consider the restrictive climate conditions for decision makers and ecological scholars, and the benefits and costs of the projects should be considered comprehensively. [ABSTRACT FROM AUTHOR]

China is one of the countries that are most severely affected by typhoon waves. Typhoon waves often cause catastrophic economic losses and human casualties in the nearshore and offshore areas of China. Risk assessments of nearshore typhoon wave disasters are of great practical significance for the prevention and mitigation of typhoon wave disasters in coastal areas. This study proposes a method of assessing the risks of typhoon wave disasters. The coupled ADCIRC and SWAN model is employed to establish a high-precision numerical model for the study area, which is then used to simulate the process of historical typhoon wave disasters, followed by a statistical analysis of the risk of disasters at the grid scale using the frequency analysis method. The modelling method is empirically analysed, taking the coastal waters from Guishan Island to Zhuhai City, Guangdong Province, as the study area. The processes of 249 typhoon wave disasters in this area were simulated, and the wave height distribution in the 100 m grid of the study area with different return periods calculated. The obtained results can serve as a basis for the development of a methodology for the assessment of typhoon wave disaster risk in coastal areas and could provide a basis for research on disaster-causing mechanisms associated with nearshore waves on the hazard-bearing body. The method proposed in this study can also be applied to other nearshore coastal waters. [ABSTRACT FROM AUTHOR]

Land use change can impact the land surface radiation budget and energy balance by changing surface biophysical processes. Based on satellite remote sensing data and land use data from 2000 to 2015, we quantitatively estimated radiative forcing induced by cropland expansion during the early 21st century in northern China. The results showed that heat flux from the land surface to the atmosphere due to cropland expansion was quite variable in different climate zones. The heat flux increased in humid North China, whereas it decreased in arid Northwest China, semiarid Inner Mongolia, and humid Northeast China. Cropland expansion from woodland areas led to a general decline in the land surface heat flux to the atmosphere, which led to a cooling effect on the climate. The surface heat flux to the atmosphere due to cropland expansion in grassland areas displayed significant variations in different climate zones. The surface heat flux decreased only in humid Northeast China and arid Northwest China. The net surface radiation and latent heat flux both increased when grasslands were changed into cropland, but to different extents, which produced the differences in the surface heat flux to the atmosphere between different zones. [ABSTRACT FROM AUTHOR]

This paper proposes a route-based model for the Train Platforming and Rescheduling Problem (TPRP). Built on the concept of Degree of Conflict (DOC), the proposed model can accommodate various interlocking mechanisms with an aggregate railway yard representation. Thanks to the topology of a typical yard, such an aggregate representation promises to reduce the size of the optimization problems concerning yard operations. The TPRP model is formulated as a mixed integer linear program, and solved using both a commercial solver and two heuristic algorithms developed based on the idea of rolling horizon. The proposed model and algorithms are validated using several case studies constructed using data collected at a large high-speed railway station in China. We find the proposed TPRP model can produce, with reasonable computation resources, high quality platform/schedule decisions for real-world applications. In addition, the heuristic algorithms consistently offer high quality approximate solutions at a computational cost considerably lower than what is demanded by a benchmark commercial solver. The results from a simulation model show the differences between various interlocking mechanisms are well captured using a unified aggregate yard representation based on DOC. As expected, more flexible interlocking mechanisms can achieve greater operational efficiency at the expense of looser safety standards. • An aggregate, route-based model for Train Platforming and Rescheduling Problem is proposed. • A novel concept, Degree of conflict (DOC), is introduced to quantify inter-route conflicts. • The model can accommodate flexible interlocking mechanisms through DOC. • Two rolling horizon algorithms are proposed to solve the mixed integer linear model. • The proposed model and algorithm are validated using numerical experiments based on real-world data. [ABSTRACT FROM AUTHOR]

Significant variations exist in water quality parameters and inherent optical properties (IOPs) in highly turbid rivers. For rivers in the Yellow River (YR) Basin, 83.33% of the collected samples exhibited high turbidity, and the absorption of non-algal particles (NAPs) was the main contributor to total water absorption. In this study, we investigated the compositions of chromophoric dissolved organic matter (CDOM) using the absorption index and fluorescence components, examined the quantitative effects of environmental factors on CDOM at the sub-basin scale and identified where and how carbon was produced in the area. The humic-like component (FR5) of CDOM was the main component in the tributaries and the main stream of the YR, especially for the Huangshui River, with FR5 accounting for 58.12%. Water quality parameters greatly affected CDOM in turbid rivers. Dissolved organic carbon and electrical conductivity were positively correlated with the CDOM concentration (p < 0.05), while dissolved oxygen, pH, chlorophyll-a and turbidity significantly affected CDOM composition (p < 0.01). Basin characteristics exerted significant influences on CDOM. The spectral slope (S 275-295) increased as the altitude of the sub-basins increased. The percentage of built-up area exerted the most significant effects on CDOM composition, with high correlations with tryptophan-like protein (FR2) and FR5 (r > 0.59, p < 0.01). Forest percentage and grassland percentage showed positive correlations with CDOM concentration (r = 0.36, p < 0.05) and S 275-295 (r = 0.30, p < 0.05), respectively. Moreover, the discharge from rivers in the YR Basin showed that the carbon flux of rivers in the YR Basin is more likely to be limited by dissolved organic matter (DOM) sources although negative but nonsignificant effects of discharges on CDOM parameters were shown. Consequently, additional research is necessary to clarify this correlation. This research is crucial and necessary for improving the accuracy of CDOM evaluation with remote sensing, revealing the influencing mechanisms and monitoring carbon cycling. [Display omitted] • Spatial patterns in CDOM concentration and composition varied greatly in the Yellow River Basin. • NAPs was the main contributor to total non-water light absorption. • Allochthonous CDOM is the main source in the studied rivers, especially in the Huangshui River. • Built-up area% exerted the most significant effects on CDOM composition. • Water quality affected CDOM concentration and composition significantly. [ABSTRACT FROM AUTHOR]

China is severely affected by storm surge disasters, which result in substantial economic losses and casualties in coastal regions. Assessing the risk of storm surge disasters can provide valuable insights into the expected losses and severity of future impacts, offering critical foresight for disaster prevention and mitigation strategies. This study assesses the quantitative risk of storm surge disasters, focusing on coastal buildings since they are particularly susceptible to storm surges and frequently bear the brunt such disasters. Xiamen city, China, was used as case study. A high-precision numerical model, using Finite Volume Community Ocean Model (FVCOM), was developed to simulate inundation during storm surges. By referencing historical storm surge records, we defined key parameters for probable maximum typhoon-induced storm surge (PMTSS) in Xiamen. These parameters were used to calculate the corresponding inundation range and water depth distribution within the region. Subsequently, the results were integrated with vulnerability curves that represent the susceptibility of buildings in Xiamen to storm surge-induced damage, enabling the quantitative risk assessment for associated loss risks. The study findings offer valuable guidance for urban planning and functional layout design in coastal areas. Furthermore, the findings contribute to understanding storm surge disaster risks and facilitating informed decision-making processes, ultimately enhancing disaster preparedness and resilience in vulnerable coastal regions. [ABSTRACT FROM AUTHOR]

Vaccination plays a crucial role in preventing and controlling SARS-CoV-2 infections as well as their associated adverse outcomes. But there is a notable lack of research on the effectiveness of COVID-19 vaccination in children, particularly those young preterm-born children, who are more vulnerable to severe outcomes from SARS-CoV-2 infection. We aimed to determine the effect of vaccination with inactivated vaccines BBIBP-CorV and CoronaVac on symptomatic COVID-19 infection and related symptoms in preterm-born children aged 3-7 years after relaxation of the COVID-19 prevention and control measures in December 2022 in China. We performed a retrospective cohort study involving 242 preterm-born children aged 3-7 years and the data were collected in March 2023. Logistic regression models and modified Poisson regression models combined with entropy balancing were used to explore the associations of vaccination against SARS-CoV-2 with symptomatic COVID-19, specific symptoms, and persistent symptoms one month after recovery from COVID-19. Of the 242 recruited preterm-born children, 156 (64.5%) were vaccinated with inactivated vaccines BBIBP-CorV and CoronaVac. After entropy balancing, the covariates were balanced between the vaccinated and the unvaccinated groups, with standardized mean difference < 0.001. Vaccination with the said SARS-CoV-2 vaccines lowered the risk of developing symptomatic COVID-19 in preterm-born children (risk ratio [RR] = 0.783; 95% confidence interval [CI]: (0.711, 0.861). Likewise, COVID-19 vaccination was associated with a decline in the risk of pneumonia (odds ratio [OR] = 0.318; 95% CI 0.110, 0.913), fever (RR = 0.710; 95% CI 0.635, 0.794), high fever (RR = 0.542; 95% CI 0.297, 0.988), sore throat (OR = 0.304; 95% CI 0.139, 0.664), and persistent symptoms (RR = 0.425; 95% CI 0.182, 0.993). Immunization with inactivated vaccines BBIBP-CorV and CoronaVac provides protection against symptomatic COVID-19 for preterm-born children 3-7 years., (© 2024. The Author(s).)

The effects of vegetable planting on soil loss and nutrient loss, runoff, soil erosion, and nitrogen (ammonium nitrogen and nitrate nitrogen) losses under individual rainfalls of fruit- and leaf-vegetable fields between April to October in 2021 were observed using in-situ observation testing. The results showed that: ① the runoff, erosion, and nitrogen loss of the fruit-vegetable pattern (eggplant-chili) were 1.27-2.00 times those under the leaf-vegetable pattern (leaf lettuce-sweet potato leaves), especially under the second season vegetable period. Those losses under the second season vegetable accounted for 50.86%-68.83% of the total losses under different vegetable patterns, which were approximately 1.03-2.04 times those under the first season vegetable. The runoff, erosion, and nutrient loss of vegetable fields under different treatments were both concentrated in June and July, and the nitrogen loss was mainly in the form of nitrate nitrogen with surface runoff. ② The runoff, erosion, and nutrient losses under individual rainfalls of vegetable fields under different treatments fluctuated among the vegetable growing season, and the losses were mainly concentrated in several typical rainfall events. On the whole, the loss and concentration of nitrate and ammonium nitrogen in runoff and erosion sediment of vegetables in the first season were lower than those in the second season. The runoff, erosion, and loss of ammonium nitrogen and nitrate nitrogen of fruit-vegetable were higher than those of leaf-vegetable. ③ Both rainfall amount and maximum 30 min rainfall intensity had significantly positive effects on runoff, soil loss, and nitrogen loss. Runoff, erosion, and nutrient losses under different vegetable patterns were mainly generated by moderate rain, heavy rain, and heavy rainstorms, which accounted for 29.58%-46.68%, 24.54%-36.79%, and 24.01%-39.13% of the total losses, respectively. The results also showed that soil erosion and nutrient losses generated by different rainfall grades were obviously different for the fruit- and leaf-vegetable treatments. The results indicated that the vegetable pattern had significant impacts on soil loss and nutrient loss, and the leaf-vegetable pattern could reduce soil erosion and nutrient loss compared with the fruit-vegetable pattern. Furthermore, for different vegetable patterns and vegetable growing seasons, the effects of rainfall on soil loss and nutrient loss were quite different. The results of this study were helpful in clarifying the soil erosion and nutrient loss characteristics of vegetable fields in South China.

A machine learning method was used to process a multiagent information database to study the spatial distribution characteristics of agglomerations of metal-related enterprises and to analyze the spatial and temporal differentiation characteristics of pollution reduction in metal-related enterprises. Based on the spatial distribution of enterprises and a simulation of their pollution reduction behaviors, the layout of 380 enterprises sample is optimized, and the direction of industrial transfer is planned to give full play to the pollution reduction effect of enterprise agglomeration. The results showed that (1) the metal-related enterprises in the Chang-Zhu-Tan urban agglomeration have obvious spatial heterogeneity and are mainly distributed in the district of Changsha, the Qingshuitang Industrial Zone, Liling city and the Qibaoshan Industrial Zone of Liuyang city, while the metal-related enterprises in Shaoshan city, Zhuzhou County and Liling city are scattered. (2) The pollution emission behaviors of enterprises differ in time and space, and the pollution concentrations are highest in industrial parks such as Qingshuitang and Zhubu Port. (3) There is an interactive relationship between the degree of enterprise agglomeration and the pollution reduction effect. The spatial positive coupling degree between the concentration of metal-related enterprises and the degree of metal-related pollution is significant, accounting for 94.96% of the study area. Low pollution-high agglomeration areas, high pollution-low agglomeration areas, high pollution-high agglomeration areas, and low pollution-low agglomeration area account for 1.01%, 4.03%, 2.87%, and 92.09% of the study area, respectively. Finally, based on the new development concept of dual circulation and the theory of a two-oriented society in the new era, the paper puts forward suggestions and policies for the sustainable development of industrial transfer., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

Background: The relationship between dietary and drinking water habits and oral health are still unclear. We aimed at evaluating the association of dietary and drinking water habits with number of teeth in the elderly adults., Methods: We conducted a longitudinal study based on the Chinese Longitudinal Healthy Longevity Survey from 1998 to 2018. The data of dietary and drinking water habits at baseline were collected using a questionnaire. The number of teeth at baseline and follow-up was collected for each subject. We used the linear mixed-effect model to analyze the associations of dietary habits and drinking water sources with tooth number., Results: Among 19,896 participants at baseline, the mean age of the participants was 83.87 years, with the average number of natural teeth of 9.37, 8.26, 8.38, 8.68, 4.05, 1.92, 1.12, 2.20 for the first to eighth waves of survey. Compared with subjects drinking tap water, 1.036 (95 % CI: -1.206, -0.865), 0.880 (95 % CI: -1.122, -0.637) and 1.331 (95 % CI: -1.715, -0.947) fewer natural teeth were reported for those drinking well, surface water and spring at baseline survey. Compared with participants with rice intake as the staple food, those with wheat intake (β = -0.684; 95 % CI: -0.865, -0.503) tended to have fewer natural teeth. Compared with participants with fresh fruit intake almost every day, those with quite often intake of fresh fruit tended to have fewer teeth with a significant dose-response trend (P trend <0.001). Similar decreased trend for number of teeth was also indicated for increased frequency of vegetable intake (P trend <0.001). Fewer number of teeth was found for subjects with less frequency of meat and fish intakes., Conclusions: The study suggested that drinking well, surface water, and spring, intakes of wheat as staple food, as well as less frequency of fresh fruit, vegetable, meat and fish intakes were associated with significantly fewer number of teeth in the Chinese elderly population., (© 2021. The Author(s).)

In order to integrate resource consumption, environmental damage and ecological benefits into the evaluation system of social and economic development, and practice the green concept of "Lucid waters and lush mountains are invaluable assets", this research was based on the Green GDP and Gross Ecosystem Product accounting to develop comprehensive accounting indicators for Gross Economic-Ecological Product (GEEP). At the same time, the 2016 GEEP of 31 provinces in China is calculated. The results show that: 1) GEEP is a comprehensive ecological-economic accounting system based on weak sustainable development theory and welfare economics. GEEP follows the principle of GDP accounting and carries out value accounting for the final products of ecological and economic systems. Based on GDP, GEEP considers the ecological-environmental damage caused by human beings in economic product activities and the benefits of the ecological system to the economic system. 2) In 2016, China's GEEP was 126.6 trillion RMB, 1.6 times of GDP, among them, the cost of pollution damage was 2.1 trillion RMB, the ecological degradation cost was 0.69 trillion RMB, and the ecosystem regulating service was 51.4 trillion RMB. 3) The regional Gini coefficient based on GEEP was 0.44, which was 0.07 smaller than the regional Gini coefficient calculated based on GDP in 2016, thus GEEP accounting would benefit to shrink regional disparity. 4) Compared GEEP ranking with GDP ranking of all provinces, GEEP rankings in Inner Mongolia, Heilongjiang, Yunnan, Qinghai and Tibet have increased by more than 10 ranks compared with GDP, and Beijing, Shanghai, Tianjin, Hebei and Shaanxi, their GEEP ranking compared with the GDP ranking has descending more than 10 places., (Copyright © 2019. Published by Elsevier Ltd.)