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In order to further understand the ecological status of the northern slope of Qinling Mountains, high-resolution remote sensing data and fuzzy analytic hierarchy process method were used to build an assessment model for the evolution of ecological security. With the analysis of spatio temporal variation and its driving factors, the ecological security status of the mountains was deeply explored. The findings reveal an overall increasing trend in the ecological security of the region, with areas rated as moderately safe or above increasing from 67.5% to 71.9%. Ecological security is generally higher in the southern than in the northern regions, displaying a clear zonal distribution pattern. The evolution of ecological security first declined and then grew, with land use, normalized vegetation index, and PM2.5 identified as the primary driving factors, with correlation indices of 0.90, 0.86, and 0.79, respectively. The results indicate that anthropogenic activities from urbanization and ecological conservation policies significantly influence the ecological security of the northern Qinling region. This study not only offers a scientific assessment of the ecological security in the mountains, but also provides robust decision-making support for regional ecological conservation and sustainable development strategies. [ABSTRACT FROM AUTHOR]

Objective: To ensure the risk level of hazardous substances in chili pepper, and analyze the unqualified situation of hazardous substances in chili pepper by combing spatial with temporal perspectives. Finally, by acquiring high- risk substances in chili pepper, and providing suggestions for efficient supervision of chili pepper safety. Methods: To evaluate the risk value of risk substances in chili pepper, the entropy method was used to calculate the risk level, and the 28 principles were used to classify and rank the risk level. In order to conduct spatiotemporal analysis of the risk substances in chili pepper, descriptive statistical methods were used for statistical description to conduct spatiotemporal analysis of the risks. Global and local autocorrelation analysis methods were used to analyze and explore the national spatial distribution patterns of high risk and high-risk substances in chili pepper. Results: Cadmium, lead, chromium, endosulfan, carbofuran and monocrotophos were high-risk substances in chili pepper; the overall change in the failure rate of chili pepper was stable from 2016--2020, and the failure rate of chili pepper in Hubei was the highest among the national provinces, and the failure of chili pepper in sampling places mainly occurs in supermarkets and farmers' markets. Conclusion: The classification results of chili pepper risk substances could improve the efficiency of government supervision, while providing a reference for enterprise self-regulation. [ABSTRACT FROM AUTHOR]

ObjectiveTo analyze prevalence trend of malaria and its spatiotemporal distribution characteristics in China for further promoting malaria control. MethodsNationwide malaria incidence data of 2010 – 2017 were collected from public health science data website of Chinese Center for Disease Control and Prevention and the population data were extracted from yearly China Statistical Yearbook of the same period. Empirical mode decomposition was adopted to identify the overall trend of malaria incidence and mathematical models were constructed to estimate variations in annual malaria incidence rate; ArcGIS 10.7 and SaTScan 9.01 software were utilized in spatial analysis of the incidence data. ResultsTotally 29 687 malaria cases were reported in mainland China during the 8-year period, primarily with vivax malaria cases aged 0 – 20 and ≥ 55 years and falciparum malaria cases aged 21 – 54 years. The overall incidence showed a significantly downward trend (odds ratio = 0.441, 95% confidence interval: 0.375 – 0.508). The hot spots of malaria incidence were mainly concentrated in the southwest border and some coastal areas of China but no obvious clustering of cold spots was observed. Totally 5 regions with spatio-temporal clustering of malaria incidence were identified and the high incidence clusters occurred mainly before 2013. Standard deviation ellipse analysis demonstrated that the region with higher malaria incidence drifted generally from southwestern area to northeastern area and the spatial range of malaria epidemic expanded to eastern provinces during the period. ConclusionFrom 2010 to 2017 in mainland China, the malaria incidence displayed downward trend generally and populations in southwestern and eastern regions were at a higher risk of malaria incidence.

Objective: To explore the epidemiological characteristics and spatiotemporal clustering of foodborne infection of Vibrio ( V. ) parahaemolyticus in Ningbo, Zhejiang Province, from 2014 to 2022, and provide reference and evidence for the prevention and control of related diseases. Methods: The incidence data on of foodborne infection of V. parahaemolyticus in Ningbo from 2014 to 2022 were collected from Ningbo Foodborne Disease Surveillance System, and the case counts and the positive rates in different districts (counties, cities) were calculated. Spatial autocorrelation analysis and spatiotemporal scanning analysis were conducted to analyze the spatiotemporal clustering of the diseases. Results: A total of 1 822 cases of foodborne infection of V. parahaemolyticus were reported in Ningbo from 2014 to 2022, with an overall positive rate of 3.78%. Spatial autocorrelation analysis showed that the positive rate of foodborne infection of V. parahaemolyticus in Ningbo was unevenly distributed from 2014 to 2022, Ninghai was a high-high clustering area, while Zhenhai was a high-low clustering area, and Jiangbei was a low-low clustering area. The annual incidence was high during July-September. Spatiotemporal scanning analysis found one class Ⅰ spatiotemporal clustering area and three class Ⅱ spatiotemporal clustering areas, with the class Ⅰ spatiotemporal clustering area being observed in Jiangbei and Zhenhai from 2019 to 2022. Conclusions: Spatiotemporal clustering of foodborne infection of V. parahaemolyticus existed in Ningbo from 2014 to 2022, with an annual high incidence period from July to September. The key areas for the prevention and control of foodborne infection of V. parahaemolyticus are coastal districts (counties, cities) in Ningbo.

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To reveal the temporal and spatial development and evolution of human H7N9 infection in China, based on the statistical data of human H7N9 infection from 2013 to 2017, time series and standard deviation ellipse analysis were performed. Firstly, the epidemic time series was analyzed with month as time unit, and the peak and trough periods of the epidemic were identified. On this basis, the whole epidemic period was divided into stages, and the epidemic change law of each stage was analyzed. Then the standard deviation ellipse is established according to the location of the epidemic cases, and the spread of the epidemic situation is described by the changes of the ellipse center, azimuth and area in each stage. Finally, through the time and space analysis of the three typical areas, the spread law of the epidemic was further verified. The results show that, the high incidence period is from December to May every year, especially in January and February. The proportion of cases in these two months is as high as 51.74%. September of every year is the low point of epidemic situation, which is the dividing point of epidemic spreading stage. During the whole epidemic period, the number of cases increased, decreased, broke out and returned to zero. Spatially, the center of the standard deviation ellipse shifts from Huzhou City to Fuzhou City and Quzhou City, and the coverage area of the ellipse also expands from coastal areas to inland areas. It shows that the early control measures are not effective enough, and the effect of prevention and control is not obvious, which makes the epidemic spread. In the later period, the strict measures had a good effect, and the epidemic situation was effectively controlled. Study the spatio-temporal transmission mechanism of human infection with H7N9, can provide a theoretical and practical reference for the prediction and Prevention of infectious diseases in China.

Vegetation net primary productivity （NPP） represents the ability of plants to fix ecosystem carbon, which is a key indicator to determine the health status and sustainable development of ecosystems. Its spatial and temporal changes and driving factors play an important role in revealing the status of vegetation restoration and guiding ecological restoration. Based on MODIS17A3 NPP data, land use, and meteorological data from 2001 to 2020, the temporal and spatial variation characteristics and driving factors of vegetation NPP in the Ulansuhai Nur Basin of Inner Mongolia were explored by using the methods of coefficient of variation, Theil-Sen Median trend analysis, Mann-Kendall significance test, Hurst index, and Geodetector. The results showed that： ① From 2001 to 2020, the vegetation NPP in the Ulansuhai Nur Basin showed a fluctuating upward trend, with an average value （in terms of C） of 141.03 g·（m 2 ·a） -1 and an average increase rate of 2.33 g·（m 2 ·a） -1 . The vegetation NPP had obvious spatial differentiation, which was characterized by high in the southwest and low in the northeast and high in Hetao Plain and low in sandy land and mountainous areas. ② NPP mainly showed an increasing trend, and the area proportions of increasing, decreasing, and unchanged areas were approximately 80%, 3%, and 17%, respectively. The average coefficient of variation of vegetation NPP was 0.149, which mainly showed low fluctuation change, and the area accounted for approximately 51%. The future change trend of NPP was mainly characterized by anti-persistence, with an area ratio of approximately 75%. ③ Land use, altitude, maximum temperature, and slope were the dominant driving factors of variation NPP change in the Ulansuhai Nur Basin, and the q values were all above 0.200. The interaction between altitude and relative humidity had the greatest explanatory power for the spatial differentiation of vegetation NPP in the Ulansuhai Nur Basin. There were significant differences in the explanatory power of land use and all factors except nighttime light to the spatial differentiation of vegetation NPP in the Ulansuhai Nur Basin. According to the research results, in the future, we should strengthen the ecosystem management of the Ulansuhai Nur Basin； continue to implement strict ecological protection and restoration policies； and comprehensively consider factors such as climate, topography, and human activities to carry out comprehensive ecological management according to local conditions to improve the quality of ecosystem services.

Objective: To investigate the spatiotemporal clustering characteristics of the reported incidence of visceral leishmaniasis (VL) in Gansu Province from 1993 to 2023, so as to provide insights into the containment of VL and prevention of VL recurrence., Methods: County (district)-level epidemical data of VL in Gansu Province from 1993 to 2023 were collected, and the geographical information database of reported VL incidence in Gansu Province was created according to the county-level administrative code and electronic maps in Gansu Province. In addition, the spatial autocorrelation analysis and hot spot analysis of the reported VL incidence were performed in Gansu Province using the software ArcGIS 10.8., Results: A total of 2 597 VL cases were reported in Gansu Province from 1993 to 2023, with an annual average incidence rate of 3.036/10 5 . Spatial autocorrelation analysis showed spatial clustering of the reported VL incidence in Gansu Province (Moran's I = 0.605, Z = 5.240, P < 0.001), appearing high-high clustering features (Getis-Ord G = 0.080, Z = 4.137, P < 0.001), and high-high clustering of the reported incidence of VL was identified in Diebu County, Tanchang County, Zhouqu County and Wenxian County. Hot spot analysis showed hot-spot areas of the reported VL incidence in Tanchang County, Zhouqu County, Wudu District and Wenxian County along the Bailong River basins and cold-spot areas in Qin'an County and Gangu County., Conclusions: There was spatial clustering and hot spots of the reported VL incidence in Gansu Province from 1993 to 2023. Intensified surveillance and control is required to prevent the spread of VL.

Objectives: To explore the spatial distribution characteristics, trend changes, and spatial clustering of esophageal cancer among residents in China at the county (city, district) scale, a spatial epidemiological approach was used, with the aim of providing localized evidence for the prevention and treatment of esophageal cancer in China. Methods: The data source was the incidence (crude rate) and mortality (crude rate) of esophageal cancer from 2005 to 2016 in the 2008-2019 edition of China Cancer Registration Annual Report published by the National Cancer Center. The Joinpoint model was used for time trend analysis. The tumor registration area in 2016 was selected as the study area for spatial feature analysis, with a total of 487 counties (cities and districts), covering 27.6% of the national population. Spatial autocorrelation analysis was performed to reveal spatial distribution characteristics by using Arcgis 10.6 software, and spatial scanning statistics was used to analyze spatial clustering characteristics by using SaTScan 9.5 software. The log-likelihood ratio ( LLR ) and relative risk ( RR ) were calculated in different windows, and the region with the largest LLR value represented the most likely cluster. Results: From 2005 to 2016, the incidence and mortality rate of esophageal cancer in China showed a trend of increasing at first and then decreasing. The incidence and mortality rate of esophageal cancer in 2016 were characterized by spatial positive correlation. High incidence and high mortality were mainly concentrated in the areas through which the Huaihe River flowed. The primary clusters (taking high incidence rate as an example LLR =6 374.41, RR =2.37, P ＜0.001) were mainly distributed in Jiangsu, Anhui and Shandong in eastern China and eastern Henan and southern Hebei in central China, and secondary clusters (taking high incidence rate as an example LLR =1 971.19, RR =1.91, P ＜0.001) in Gansu, Ningxia Hui Autonomous Region, Shaanxi, Sichuan and other central and western regions. Conclusions: The incidence and mortality of esophageal cancer in China have decreased since 2010. The disease burden of esophageal cancer has obvious spatial differences, and measures should be taken according to local conditions in high-risk cluster areas such as the Huaihe River basin.

To evaluate the spatiotemporal trends and drivers of PM 2.5 -related health effects in Gansu Province since the implementation of the Air Pollution Prevention and Control Action Plan, the latest global exposure mortality model （GEMM） was adopted to estimate the health burden attributable to PM 2.5 in Gansu Province from 2013 to 2020. The factor decomposition method was used to further quantify the main causes of the long-term changes in deaths attributable to PM 2.5 pollution. The results showed that from 2013 to 2020, the population-weighted PM 2.5 concentration in Gansu Province decreased by 34.57%, and the proportion of people exposed to areas with an annual average PM 2.5 concentration exceeding 35 μg·m -3 decreased significantly from 72.89% to 11.61%. Moreover, the number of attributable deaths in Gansu Province declined from 12 826 （95%CI： 7 840-17 408） in 2 013 to 9 814 （95%CI： 6 407-13 036） in 2020, indicating a decrease of 23.48%. Attributable deaths from stroke, chronic obstructive pulmonary disease, lung cancer, and lower respiratory infection declined, whereas deaths from ischemic heart disease increased by 12.11%. Notably, individuals aged 60 years and older accounted for more than 80% of all age-related deaths. The number of deaths attributable to PM 2.5 in central and eastern Gansu Province was significantly higher than that in the Hexi region, and most regions showed a downward trend. The contribution of the total population, age structure, baseline mortality rate, and PM 2.5 concentration to the change in PM 2.5 -related deaths was -1.26%, 16.16%, -9.84%, and -28.55%, respectively. Overall, population aging and a decrease in PM 2.5 concentration were the main factors contributing to the increase and decrease in PM 2.5 -related deaths, respectively. The active clean air policies in Gansu Province have reduced the health burden caused by PM 2.5 pollution, but with the trend of population aging, a significant reduction in PM 2.5 concentration will be needed in the future to avoid more attributable deaths.

Rivers are important reservoirs of antibiotic resistance genes (ARGs). However, most current studies have focused on the temporal and spatial distribution, and data on the differences in the species and abundance of ARGs between urban and rural rivers is still lacking for certain areas. In view of this, two rural rivers and three urban rivers were selected in Shijiazhuang City. In both December 2020 and April 2021, sediments were collected at 15 sampling sites. Metagenomic sequencing technology was used to compare the differences in temporal-spatial variation for ARGs in sediments. The results showed that:① 162 and 79 ARGs were detected in urban (4 776 ±4 452) and rural rivers (1 043 ±632), respectively. The abundance and species of ARGs in urban rivers were higher than those in rural rivers. ② The relative abundances of sulfonamide (SAs,27 %), aminoglycoside (AGs,26 %), and multidrug (MDs,15 %) ARGs had the highest abundance in urban rivers, whereas the relative abundance of MDs ARGs was highest in rural rivers (65 %). On the whole, the complexity of ARGs in urban rivers was higher than that in rural rivers. ③ There was a significant positive correlation between SAs, AGs, MDs, tetracycline, phenicol, macrolides-lincosamids-streptogramins (MLS), β -lactams, and diaminopyrimidine ARGs in urban rivers ( P &lt; 0.01); however, there was a significant negative correlation between glycopeptide ARGs and all types of ARGs ( P &lt; 0.05 and P &lt; 0.01). There was a significant positive correlation between MDs and SAs ARGs in rural rivers ( P &lt; 0.05), but there was a significant negative correlation between amino aminocoumarin, peptide, rifamycin, and fosfomycin ARGs ( P &lt; 0.05 and P &lt; 0.01). ④ For the temporal variation in urban rivers, 162 ARGs (4 776 ±4 452) and 148 ARGs (5 673 ±5 626) were detected in December and April, respectively. For the temporal variation in rural rivers, 79 species (1 043 ±632) and 46 species (467 ±183) were detected in December and April, respectively. ⑤ RDA analysis results showed that the spatial-temporal distributions of ARGs in urban and rural rivers were different. Correlation analysis showed that the ARGs in urban rivers were significantly correlated with the number of industrial enterprises, whereas the ARGs in rural rivers were significantly correlated with the output value of animal husbandry. In general, this study identified the main influencing factors for ARGs in different rivers and provided data support for ARGs risk management in different rivers.

Site contamination has caused serious harm to human health and the ecological environment, so understanding its spatial and temporal distribution patterns is the basis for contamination assessment and site remediation. For this reason, this study analyzed the spatial-temporal distribution patterns of organic pollutants and their driving factors in the Yangtze River Delta based on site sampling data using the optimal-scale geographical detector. The analysis results showed that:① There was a significant scale effect in the spatial distribution of organic pollutants in the Yangtze River Delta, and its optimal geographic detection scale grid was 8 000 meters. ② The main control factor of the spatial distribution of pollutants in the Yangtze River Delta originated mostly from the biological field, followed by the chemical field. ③ At the depth of 0-20 cm of soil, the explanatory power of sucrase content, urease content, microbial nitrogen amount, total nitrogen content, and cation exchange amount were stronger for the spatial distribution of organic pollutants. At the soil depth of 20-40 cm, the factors with stronger explanatory power on the spatial distribution of organic pollutants were soil moisture, population, and total nitrogen content. With the deepening of soil depth, the explanatory power of the factors of the hydrodynamic field increased. ④ Population, total nitrogen content, and polyphenol oxidase content had stronger explanatory power for the spatial distribution of organic pollutants in the spring. The spatial distribution of organic pollutants was more complex in autumn, and the factors showed stronger enhanced-nonlinear and enhanced-bi phenomena.

Xi'an is the political, economic, and cultural center of northwest China with a developed industry. Air pollution incidents have brought great challenges to the high-quality development of the social economy. It is vital to study air pollution characteristics and clarify their impact on human health. In this study, we first analyzed the spatiotemporal variations in air pollutants in the study region from 2015 to 2021. Then, the air quality index (AQI), aggregate air quality index (AAQI), and health risk-based air quality index (HAQI) were used to assess health risks. Based on these, the AirQ 2.2.3 model was used to quantify health effects. The results showed that the major pollutants were PM 10 , PM 2.5 , and O 3 . The main pollution characteristics of the study area were terrain characteristics and the mixed pollution of anthropogenic emissions. Compared to that of AQI, AAQI and HAQI showed better classification performance for pollution levels. HAQI revealed that approximately 80 % of the population was exposed to unhealthy air throughout the year in the study region. People were most exposed to unhealthy air in winter, followed by autumn and spring, and the least in summer. The AirQ 2.2.3 model quantified the total mortality proportions attributable to PM 2.5 , PM 10 , SO 2 , CO, NO 2 , and O 3 , which were 0.99 %, 2.04 %, 0.41 %, 1.72 %, 8.76 %, and 3.67 %, respectively. The attributable proportion of mortality of the respiratory system and cardiovascular diseases was consistent with the change rule of total mortality.

Exploring the temporal and spatial dynamics of vegetation coverage in the Heilongjiang Basin and its response to climate change can provide a theoretical basis and data support for integrated basin management for three countries (Mongolia, China and Russia) in the region. We used MOD13Q1 remote sensing data from Google Earth Engine (GEE) platform between 2000 and 2020 to process the normalized vegetation index (NDVI) through the maximum value composites method, and calculated the vegetation coverage (FVC) using the dimidiate pixel model. The Sen+MK trend analysis method was employed to monitor the dynamics of FVC, while the Pearson correlation coefficient was utilized to quantify the responses of FVC to climate change. The results showed that the overall FVC in the Heilongjiang Basin exhibited a slight decreasing trend during 2000-2020, with an annual rate of 0.1%. The FVC in Mongolia showed a fluctuating increase trend (0.13%), while slight decrease trends were observed for Russia (0.15%) and China (0.08%). The FVC predominantly slightly degraded and severely degraded, accounting for 34% and 17% of the area, respectively, while the significantly improved area only accounted for 9%. The impact of precipitation on FVC in the study area was significantly greater than that of temperature. The proportion of areas where precipitation and temperature had a significant impact on FVC was 8.2% and 2.2%, respectively. The correlation coefficient between precipitation and FVC was the highest in Mongolia ( r =0.446, P <0.05), and the lowest in Russian region ( r =-0.442, P < 0.05).

Reference crop evapotranspiration (ET 0 ) is a crucial variable for estimating the ecological water demand of vegetation. Under climate change, the trends of ET 0 change vary in different regions. The study of spatial and temporal variations in ET 0 and attribution analysis at the regional scale is more conducive to the regional agricultural water management and ecological water demand estimation under the changing environment. We analyzed the change trend, spatial distribution and the contribution of meteorological factors to annual ET 0 change of the Fenwei Plain during a historical period (1985-2015) and a future period (2030-2060) based on the latest climate data and high-precision grid data from the Sixth International Coupled Model Intercomparison Project (CMIP6). The results showed that the meteorological data from CMIP6 could be used for the prediction of ET 0 after bias correction, and that the prediction accuracy of the multi-model ensemble approach ( R 2 of 82.9%, RMSE of 14.9 mm) was higher than that of a single climate model. ET 0 in the Fenwei Plain showed a significant decreasing trend in the historical period, but a non-significant increasing and significant increasing trend in the future period under the SSP245 and SSP585 scenarios, respectively. The vapor pressure deficit had the largest contribution to the ET 0 change in both the historical and future periods, and was the primary meteorological factor affecting the ET 0 change in the Fenwei Plain under the climate change. Solar radiation and wind speed were important meteorological factors affecting the ET 0 change in the historical period, while temperature and wind speed were the important meteorological factors affecting the ET 0 change in the future period. The meteorological factors that had great contribution to ET 0 change were due to the larger multi-year relative change rates, rather than the high sensitivity of these meteorological factors to ET 0 . The ET 0 of the plain under the SSP245 and SSP585 scenarios increased by 4.2% and 3.1% in the future period, respectively, compared with the historical period. The differences in the spatial distribution of the result were mainly from the eastern and western regions of the plain. Based on the high-precision spatial and temporal distribution of ET 0 , the spatial and temporal data could be used as a reference for the development of various adaptation for climate change in the Fenwei Plain.

Spatial variability of throughfall ( i.e. the non-uniform characteristics of throughfall at different canopy positions) and its temporal persistence ( i.e. time stability) are related to the quantity and efficiency of soil moisture replenishment, and affect plant competition and community succession dynamics by affecting resource availability. We carried out a meta-analysis with 554 papers (from 2000 to 2022) retrieved from Web of Science and China National Knowledge Infrastructure (CNKI) based on keyword search, quantified and compared the amount, spatial heterogeneity, and temporal stability characteristics of penetrating rain in different climate zones and plant functional types. Our results that throughfall proportion was lower in arid regions (72.0%±13.6%) than humid (75.1%±9.3%) and semi-humid areas (79.9%±10.4%). Cold climates had lower values (74.1%±14.6%) than temperate (74.2%±7.5%) and tropical climates (80.9%±14.6%). Shrubs (68.9%±14.9%) generally had lower throughfall proportion than trees (76.7%±9.1%). Broad-leaved trees (75.2%±11.1%) and conifers (75.1%±9.9%) showed similar throughfall proportions, as did evergreen (76.7%±10.0%) and deciduous species (74.7%±11.9%). Additionally, spatial variability (coefficient of variation) did not significantly differ across rainfall zones, temperature zones, or vegetation types. The spatial distribution of throughfall was relatively stable. Canopy structure was the dominant factor affecting temporal stability of throughfall. However, there was a lack of comparison between typical geographic units ( i.e. spatial units with basically consistent geographical environmental conditions) at various temporal scales. Future research should expand upwards to the summary of global spatial scale rules and downwards to the analysis of process based temporal scale mechanisms, to depict the dynamic distribution of penetrating rain and unify observation standards to enhance comparability of different studies, in order to efficiently promote research on canopy penetrating rain and provide ecological and hydrological basis for protecting nature, managing artificial activities, and restoring degraded ecosystems.

Objective. To get the spatio-temporal distribution of the syphilis epidemic in 31 provinces, municipalities directly under the Central Government and autonomous regions of the mainland of China in 2017. Methods. The data of syphilis incidence in 31 provinces, municipalities and autonomous regions of the mainland of China in 2017 were obtained from the China Public Health Science Data Center, and the time distrbution characteristics of the incidence rates were described. The global Moran's I index and Anselin local Moran's I index were used to analyze the spatial cluster characteristics of the syphilis cases, and then space-time scan analysis based on Poisson distribution was used to explore the spatio-temporal distribution characteristics. Results. In 2017, the number of syphilis cases in the 31 provinces, municipalities, and autonomous regions of the mainland of China was 475 860, and the incidence rate was 34.49/100 000. Latent syphilis accounted for most of the cases, reaching 76.78% (365 353/475 860). August had the highest incidence rate. For the spatial distribution, Xinjiang Uygur Autonomous Region was the provincial-level unit with the highest incidence rate of syphilis, reaching 91.80/100 000. The incidence rates of latent, secondary, tertiary, and congenital syphilis appeared with positive spatial autocorrelation (all P<0.05). The high-high clusters of secondary and tertiary syphilis appeared in Shanghai, Jiangsu, and Zhejiang (all P<0.05), respectively, while the high-high clusters of congenital syphilis appeared in Xinjiang and Tibet (P=0.000). The results of space-time scan analysis showed that the main cluster appeared from April to September in Fujian, Jiangxi, Zhejiang, Shanghai, Jiangsu, Hunan, Anhui, and Guangdong (P=0.000). Compared with the outside area, the relative risk of syphilis in this cluster was 1.59 times. Conclusion. The incidence rate of syphilis in China is relatively high. There are differences in the types and periods of syphilis prevention and control among provinces, municipalities and autonomous regions. From April to September, Fujian, Jiangxi, Zhejiang, Shanghai, Jiangsu, Hunan, Anhui and Guangdong are the key areas for syphilis prevention and control in the mainland of China. [ABSTRACT FROM AUTHOR]

To analyze the spatiotemporal distribution and clusters characteristics of human immunodeficiency virus( HIV)/acquired immune deficiency syndrome (AIDS) patients in Rongchang District of Chongqing from 2014 to 2019, we provide reference for relevant departments to clarify the focus of AIDS prevention and control and rationally allocate medical and health resources. Methods Newly identified HIV/AIDS in Rongchang Area from 2014 to 2019 were selected from the National HIV/AIDS Comprehensive Information System. We inputted data into GeoDa 0.95i software for carry out spatial empirical bayesian smoothing and autocorrelation analysis, and into Satscan 9.3 software for statistical analysis of spatial scanning, and finally geographic information system was used for visualization. Results A total of 1 476 new cases of HIV/AIDS were reported in Rongchang District during 2014-2019. The proportion of cases over the aged≥50 years reported in each year ranged from 58.74% to 68.92%, and increased year by year (χ² trend = 4.524, P = 0.033). There was a positive spatial autocorrelation in the spatial distribution of the HIV/AIDS reporting rate for each year (Moran's I > 0, P <0.05). The areas with the most serious HIV/AIDS epidemics, including urban areas (Changyuan Street, Changzhou Street) and the neighboring Fenggao Street, Wanling Town, Zhisheng Town and other towns (streets) in the east were Rongchang AIDS-endemic areas, were identified with both the local Moran's I index and spatiotemporal scan statistics. Conclusion Geographical differences and spatial clustering were identified in HIV/AIDS cases in Rongchang District. For the further prevention and control of the hot-spot regions expanding, the government must strengthen monitoring of the migrating population in hotspots, and strengthen AIDS interventions for middle-aged and elderly people and low-fee sex workers, while further standardize the follow-up management of AIDS in medical institutions at all levels. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Hebei University of Science & Technology is the property of Hebei University of Science & Technology, Journal of Hebei University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Metropolitan integration development refers to the interconnection between cities and the coordinated development of various aspects such as economy, society, culture, and nature, which is the goal of metropolitan area development. With the Zhengzhou metropolitan area as the research area and based on nighttime light data from 2012 to 2021, we comprehensively used landscape index and landscape morphology spatial pattern analysis methods, systematically evaluated the integration process of the metropolitan area from the perspective of spatial expansion and spatial connection, analyzed the spatiotemporal variations of the landscape pattern of the metropolitan area, and revealed the spatiotemporal expansion and connection patterns of the metropolitan area. The results showed that the area of the Zhengzhou metropolitan area expanded year by year from 2012 to 2021, with the number of landscape patches continuously increasing, showing an agglomeration phenomenon. In the metropolitan area, there was a trend towards stability and multi-directional coordinated growth. The contribution of non-central cities to expansion increased annually, while the expansion patterns of various constituent cities gradually shifted from internal filling to external expansion. The connection scale within the metropolitan area had been expanding annually, with enhanced intercity connections. Intercity connection belts and channels for material and information exchange were emerging, and the integrated network of urban agglomeration connections was gradually forming. Metropolitan integration planning provided positive guidance for the development of metropolitan areas. We should fully leverage the driving effects of metropolitan areas, pay attention to the integration of Zhengzhou-Kaifeng and Zhengzhou-Xuchang, promote the formation of emerging growth poles in Xinxiang and Jiaozuo, as well as regional coordinated development, strengthen the network of policies, economy, transportation, information, etc., and form a diversified and integrated development situation.

To explore the temporal and spatial variations in phytoplankton community in small estuaries, we collected surface water samples from Yongjiang River estuary during wet, normal, and dry seasons and determined the main driving factors of phytoplankton community. A total of 358 species belonging to nine phyla and 123 genera were identified in all seasons. During wet, normal, and dry seasons, species number was 276, 154 and 151, and the abundance was (170.45±225.43)×10 3 , (51.92±30.28)×10 3 and (31.65±12.79)×10 3 cells·L -1 , respectively. Diatoms dominated the phytoplankton community, and the main dominant species were Cyclotella meneghiniana , Skeletonema costatum , and Paralia sulcata . Shannon diversity and Pielou evenness indices decreased from inside mouth to outside mouth in wet season, but there was no obvious spatial difference in normal season or dry season. Results of non-metric multidimensional scaling analysis and analysis of similarities showed that phytoplankton community composition differed significantly among different regions (inside, at and outside mouth) and different seasons. In wet season, phytoplankton abundance was significantly positively correlated with temperature, dissolved inorganic nitrogen, and dissolved reactive phosphorus, but significantly negatively correlated with salinity. In normal season, phytoplankton abundance was significantly negatively correlated with temperature. In dry season, it was not significantly correlated with environmental factors. Results of redundancy analysis showed that temperature, salinity, ammonium and dissolved reactive phosphorus explained the variations in phytoplankton community by 19.5%, 11.9%, 9.4% and 8.2%, respectively. These results revealed high dominance of diatoms and the main driving factors (temperature, salinity and nutrients) of phytoplankton community in Yongjiang River estuary.

Understanding the spatiotemporal variations and driving factors of regional vegetation coverage is crucial for developing scientific plans for ecological environment protection and maintaining regional ecological balance. Based on the Google Earth Engine (GEE) platform and using Landsat Collection 2 data, we investigated the spatiotemporal variation and driving factors of vegetation coverage in Shanxi Province, China, from 1990 to 2020, by employing methods such as pixel-based binary model, trend analysis, zonal statistics, and geodetector. The results showed that vegetation coverage in Shanxi Province showed a fluctuating upward trend from 1990 to 2020. Vegetation coverage in 44.4% of this region had been significantly improved, and the area with significant degradation accounted for 7.4%. Vegetation coverage in Shanxi Province was positively correlated with elevation, slope, and mountain terrain relief. The area proportion of vegetation coverage growth was the highest in the plateau and hilly regions. Factor detection results showed that land use type, landform type, annual average precipitation, and soil type were the main influencing factors of the spatial differentiation of vegetation coverage in Shanxi Province. Results of the interaction detection showed that the interaction between driving factors all showed enhancement. The interaction between natural factors showed a downward trend, while the interaction results of social factors showed an upward trend, reflecting that the impacts of human activities on vegetation coverage in Shanxi Province were gradually increasing.

Objective: To analyze the spatial-temporal distribution of etiologically positive pulmonary tuberculosis (PTB) at the county (city, district) unit in Jiangsu Province from 2011 to 2021 to provide evidence for the implementation and adjustment of prevention and control strategies of PTB in Jiangsu Province. Methods: The registration data of etiologically positive PTB patients in Jiangsu Province from 2011 to 2021 were collected from the Tuberculosis Management Information System in the China Information System of Disease Control and Prevention. Data on the permanent population were from the statistical yearbook of each county (city, district) in Jiangsu Province. Geoda 1.18.0 software was used to analyze the global and local spatial autocorrelation and explore the spatial clustering. SaTScan 10.1 software was used to analyze the spatial-temporal clusters, and ArcGIS 10.7 software was used to visualize the spatial-temporal clusters. Results: A total of 128 240 etiological positive PTB cases were registered in Jiangsu Province from 2011 to 2021, with an average annual registration rate of 13.99/100 000. The registration rate showed an overall upward trend (trend χ 2 =63.49, P <0.001) after 2017, and the etiologically positive rate showed an overall upward trend (trend χ 2 =3 710.86, P <0.001). The annual Moran's I values ranged from 0.107 to 0.343, which showed a spatial clustering distribution. The results of local spatial autocorrelation analysis showed that there were "high-high" clustering areas in Jiangsu Province each year, showing a dynamic distribution, and most of the areas were distributed in the central and southern regions of Jiangsu Province, with the largest number (7) in 2015 and the smallest number (1) in 2011. A total of 4 spatial-temporal clustering areas were explored by spatial-temporal scanning analysis (all P <0.001), among which the first-level clustering area covered 3 counties (cities, districts), namely Changshu, Taicang, and Xiangcheng District of Suzhou, and the clustering time was from 2011 to 2015. The secondary clustering areas covered 24 counties (cities, districts), mainly covering Jiangsu's central and northern regions, such as Huai'an, Suqian, and Yancheng. The third-level clustering areas covered 26 counties (cities, districts); the fourth-level clustering area was the Gaochun District of Nanjing, with the clustering period from 2017 to 2021. Conclusions: From 2011 to 2021, the etiologically positive PTB registration rate at the county (city, district) level in Jiangsu Province had obvious spatial-temporal clustering characteristics. The clustering areas included the northern areas with relatively backward economies and the southern areas with better economic development. Multiple measures should be taken to prevent and control PTB according to the specific situation in different regions.

Objective To explore the epidemic trend and spatio-temporal characteristics of colorectal cancer in Jiading District of Shanghai，China，and to provide evidence for prevention and control of colorectal cancer and rational allocation of health resources. Methods The data of colorectal cancer in Jiading District of Shanghai from 1996 to 2016 was collected.The incidence rate was calculated，and spatial and temporal scanning was used to analyze the spatial aggregation of colorectal cancer. Results From 1996 to 2016，a total of 4 279 cases of colorectal cancer were reported in Jiading District of Shanghai，with a crude incidence of 36.2/100 000 and a standardized incidence of 16.4/100 000.Colon cancer accounted for 58.0%，the standardized incidence of colon cancer was on the rise with fluctuation. The number and incidence of rectal cancer were lower than that of colon cancer，accounting for 42.0%. The standardized incidence of colon and rectal cancers were generally higher in male than in female，and the standardized incidence of colon and rectal cancer by town had significant differences.In addition，a cluster was detected by spatial scanning statistics. We also found that the age distribution of 2 clusters of colon cancer and 1 cluster of rectal cancer were statistically different from that of the remaining areas outside the circle. Conclusion The incidence of colorectal cancer in Jiading District of Shanghai showed an upward trend， and the incidence of colorectal cancer may have a tendency of spatial aggregation.The results of this study can provide reference for the prevention and resource allocation of colorectal cancer. [ABSTRACT FROM AUTHOR]

Objective: To analyze the spatial-temporal epidemiological characteristics of pertussis from 2013 to 2022 in Hebei Province and to provide a reference for improving prevention and control measures. Methods: Based on the data of pertussis reported in Hebei Province during 2013-2022 to analyze the popular characteristic, the ArcGIS 10.8 software was used to construct a ring map and to perform spatial autocorrelation analysis; the SaTScan 10.1 software was used for spatial-temporal scan statistics. Results: There were 6 715 cases of the cumulative report in Hebei Province from 2013 to 2022 without death. The annual report incidence was 0.90/100 000. The overall incidence rate showed an upward trend from 2013 to 2019, and during 2020-2021, it showed a sharp decline, but in 2022, it showed a sharp increase. Summer and autumn are the peak seasons of the epidemic. The incidence was highest in age group <1 year (48.67%), and the lowest age group in age group ≥15 years (0.45%) and mainly scattered children (78.03%); the incidence about men is higher than women. Spatial autocorrelation analysis showed that the onset of pertussis has spatial clustering, and high-high clusters were found in Langfang, Baoding, and Cangzhou, the top three countries with reported incidence. The area covered by a low-low cluster was consistent with the distribution of the corresponding low-incidence areas in this study. Space-time scan detects five statistically significant areas, and three zones were concentrated in 2022. Conclusions: The incidence of pertussis in Hebei had obvious season, population, and area-specific differences. There was obvious spatiotemporal and clustering, so the control of key areas should target the characteristics of time and space.

Objective: To explore the temporal and spatial distribution characteristics of reported incidence of schizophrenia in Ningbo from 2018 to 2022 and to provide a scientific basis for rational allocation of mental health resources and comprehensive prevention and treatment of schizophrenia. Methods: The reported incidence data of schizophrenia from 2018 to 2022 were collected from Ningbo's mental health information management system, and the reported incidence was calculated by township. The spatial correlation analysis and the spatiotemporal scan analysis were used to study the spatiotemporal distribution of schizophrenia. Results: The reported incidence of schizophrenia decreased from 2018 to 2022, with 4 133 new cases reported, and the annual average reported incidence was 9.76/100 000. Global and local spatial autocorrelation analysis showed positive spatial correlations and hot spots in 2018-2020. The space-time scan analysis showed an incidence cluster in Dongqiao Town, Haishu District, during 2018-2019. The RR was 2.46, and the log-likelihood ratio was 256.89. Conclusions: The reported incidence of schizophrenia in Ningbo has obvious temporal and spatial aggregation, and the high incidence area explored can provide clues for further research on the correlation between environmental factors and the incidence of schizophrenia and has certain guiding significance for the rational allocation of mental health resources in Ningbo.

Coordinated development by coupling land use intensity with socio-economic factors can promote the sustainable development of cities effectively. We applied the multi-factor comprehensive evaluation method based on the entropy value method to appraise land use intensity and socio-economic development levels in nine categories of cities in the Jilin Province. On the basis of this, coupling coordinative degree and space autocorrelation model were employed to quantitatively analyze the spatio-temporal coupling coordinated development status between the two. The result indicates that the intensive land utilization and socio-economic development levels show a gradual upward trend in all the nine levels of cities in the Jilin Province. Moreover, it appears that the center was spatially higher than the east and the west from 2005 to 2015. From 2005 to 2015, the degree of coordination between intensive land use and socio-economic development in various cities in the Jilin Province was gradually optimized with some effort, while the relative development degree gradually decreased. From the view of the spatio-temporal coupling development status, coupling compatibility and geographic mobility appear obscure during the study period in the nine levels of cities in the Jilin Province. Local analysis demonstrates that Jilin and Changchun belong to a high value polarization region, while Siping, Liaoyuan, Baishan, and Tonghua belong to a low value subsidence area. Songyuan has become a high value polarization region from the low limit area, Yanji has shifted from the non-significant distribution into high-value diffusion distribution, while Baicheng shows nonsignificant distribution overall. [ABSTRACT FROM AUTHOR]

This paper studied the time and space distributions of city-scaled residents by making use of 3G mobile network data, and proposed a spatio-temporal forecasting model of cellular population. The inspiration came from the real world accumulation and dispersion of crowd. For importing the dynamic mobility, this model could avoid the effect of data smoothing widely embedded in previous models based on time series and overall space data. Through experimental verification, this model has been proved that it owns a better prediction performance on a fine-grained scale, especially in the prediction of incident crowd. This study and mode helps to belter understand the crowd distribution and provide support for wireless network base station research. [ABSTRACT FROM AUTHOR]

Objective: To investigate the incidence trend and spatial clustering characteristics of scarlet fever in China from 2016 to 2020 to provide evidence for development of regional disease prevention and control strategies., Methods: The incidence data of scarlet fever in 31 provinces and municipalities in mainland China from 2016 to 2020 were obtained from the Chinese Health Statistics Yearbook and the Public Health Science Data Center led by the Chinese Center for Disease Control and Prevention.The three-dimensional spatial trend map of scarlet fever incidence in China was drawn using ArcGIS to determine the regional trend of scarlet fever incidence.GeoDa spatial autocorrelation analysis was used to explore the spatial aggregation of scarlet fever in China in recent years., Results: From 2016 to 2020, a total of 310 816 cases of scarlet fever were reported in 31 provinces, municipalities directly under the central government and autonomous regions, with an average annual incidence of 4.48/100 000.The reported incidence decreased from 4.32/100 000 in 2016 to 1.18/100 000 in 2020( Z =103.47, P < 0.001).The incidence of scarlet fever in China showed an obvious regional clustering from 2016 to 2019(Moran's I>0, P < 0.05), but was randomly distributed in 2020(Moran's I>0, P =0.16).The incidence of scarlet fever showed a U-shaped distribution in eastern and western regions of China, and increased gradually from the southern to northern regions.Inner Mongolia Autonomous Region and Hebei and Gansu provinces had the High-high (H-H) clusters of scarlet fever in China., Conclusion: Scarlet fever still has a high incidence in China with an obvious spatial clustering.For the northern regions of China with H-H clusters of scarlet fever, the allocation of health resources and public health education dynamics should be strengthened, and local scarlet fever prevention and control policies should be made to contain the hotspots of scarlet fever.

Considering the large volumes of floating car data, the lower real-time and map matching rate of map matching algo-rithm in current urban transportation, this paper proposed a map-matching algorithm based on spatio-temporal analysis. On the basis of grid index building for urban road network, this algorithm considered the spatial geometric, topological structures info of the road network and the impact on the selection of GPS point's projection, which greatly enhanced the matching efficiency and improved the matching accuracy. The experiment proves that this algorithm can meet the requirement of real-time performance and accuracy of floating car map matching in the practical application. [ABSTRACT FROM AUTHOR]

Objective: To analyze the epidemiology and spatial-temporal distribution characteristics of hand, foot and mouth disease (HFMD) in Shanxi province. Methods: The data of HFMD in Shanxi province from 2009 to 2020 were collected from notifiable disease management information system of Chinese information system for disease control and prevention and analyzed by descriptive epidemiology, Joinpoint regression, spatial autocorrelation analysis and spatio- temporal scanning analysis. Results: A total of 293 477 HFMD cases were reported in Shanxi province from 2009 to 2020, with an average annual incidence of 67.64/100 000 (293 477/433 867 454), severe disease rate of 5.36/100 000 (2 326/433 867 454), severe disease ratio of 0.79%(2 326/293 477), mortality of 0.015/100 000 (66/433 867 454), and fatality rate of 22.49/100 000 (66/293 477). The reported incidence rate, severe disease rate, mortality rate and fatality rate of HFMD showed decreasing trends. The main high-risk groups were scattered children and kindergarten children aged 0-5. The incidence of HFMD had obvious seasonal variation, with two peaks every year: the main peak was during June-July, the secondary peak was during September-October and the peak period is from April to November. A total of 13 942 laboratory cases were confirmed, with a diagnosis rate of 4.75% (13 942/293 477), including 4 438 (35.11%, 4 438/293 477) Enterovirus A71 (EV-A71) positive cases, 4 609 (33.06%, 4 609/293 477) Coxsackievirus A16 (CV-A16) positive cases, and 4 895 (31.83%, 4 895/293 477) other enterovirus positive cases. There was a spatial positive correlation (Moran's I ranged from 0.12 to 0.58, all P <0.05) and the spatial clustering was obvious. High-risk regions were mainly distributed in Taiyuan in central Shanxi province, Linfen and Yuncheng in southern Shanxi province, and Changzhi in southeastern Shanxi province. Spatial-temporal scanning analysis revealed 1 the most likely cluster and 8 secondary likely clusters, of which the most likely cluster ( RR =2.65, LLR =22 387.42, P <0.001) located in Taiyuan and Jinzhong city, Shanxi province, including 12 counties (districts), and accumulated from April 1, 2009 to November 30, 2018. Conclusions: There was obvious spatial-temporal clustering of HFMD in Shanxi province, and the epidemic situation was in decline. The key areas were the districts in urban areas and the counties adjacent to it. Meanwhile, the monitoring and classification of other enterovirus types of HFMD should be strengthened.

Qinghai-Tibet Plateau is a "climate change laboratory" for China and the world. Driven by climate change, net primary productivity (NPP) in the Qinghai-Tibet Plateau has significant variations. Using the data of normalized difference vegetation index, digital elevation, annual precipitation, and annual temperature, we explored the temporal and spatial variation characteristics of NPP and its correlation with climate factors on the Qinghai Tibet Plateau from 2000 to 2020. The results showed that NPP of the Qinghai-Tibet Plateau increased significantly from 2000 to 2020, with an increase rate of 1.67 g C·m -2 ·a -1 . The NPP was significantly positively correlated with temperature and precipitation. The climate trend of warming and wetting was an important driving force to promote the significant increase of NPP. The increases of NPP would continue if the climate become warmer and wetter.

The optimal intensity of urban land use is determined by the urbanization development level so it is necessary to explore the spatial-temporal pattern of the coordination between urban land use and urbanization. This paper establishes a comprehensive evaluation index system of the coordination coefficient between urban land intensive use system and urbanization system. Based on the software SPSS16.0 and ArcGIS9.2, the measurement and evolution of the coordination coefficient in the Bohai Rim Region from 1990 to 2008 are analyzed spatially and temporally. The results show that the level of the coordination coefficient between urban land intensive use system and urbanization system in the Bohai Rim Region is still fairly low, and urban land intensive use lags behind urbanization at the large extents. The spearman rank correlation coefficient shows that the coordination coefficient in the Bohai Rim Region has been improving continuously, especially the Shandong peninsula urban agglomeration is the area with most rapid development. The global Moran's Index shows that the distribution of the coordination coefficient in the Bohai Rim Region random from 1990 to 2008 with no significant polarization effect. The proliferation of high-value area is concentrating on Jing-Jin-Ji circle and the Liaodong peninsula. Along with the urbanization and the expansion of urban size, the catalytic effect of urbanization system on urban land intensive use system tends to weaken, even it has been playing a principal role in recent 20 years. As stated previously, with the rapid expansion of city scale and the increasing of urbanization, the development trend of the coordination coefficient between urban land intensive use system and urbanization system will be well fitted to Logistic curves. [ABSTRACT FROM AUTHOR]

Objective: Based on the geographic information systems, we exploreed the spatiotemporal clustering and the development and evolution of COVID-19 epidemic at prefectural level in China from the time when the epidemic was discovered to the time when the lockdown ended in Wuhan. Methods: The information and data of the confirmed COVID-19 cases from December 8, 2019 to April 8, 2020 were collected from 367 prefectures in China for a spatial autocorrelation analysis with software GeoDa, and software ArcGIS was used to visualize the results. Software SatScan was used for spatiotemporal scanning analysis to visualize the hot-spot areas of the epidemic. Results: The incidence of new cases of COVID-19 had obvious global autocorrelation and the partial autocorrelation results showed that incidence of COVID-19 had different spatial distribution at different times from December 8, 2019 to March 4, 2020. There was no significant difference in global autocorrelation coefficient from March 5, 2020 to April 8, 2020. The statistical analysis of spatiotemporal scanning identified two kinds of spatiotemporal clustering areas, the first class clustering areas included 10 prefectures, mainly distributed in Hubei, from January 13 to February 25, 2020. The secondary class clustering areas included 142 prefectures, mainly distributed in provinces in the north and east of Hubei, from January 23 to February 1, 2020. Conclusions: There was a clear spatiotemporal correlation in the distribution of the outbreaks in the early phase of COVID-19 epidemic (December 8, 2019-March 4, 2020) in China. With the decrease of the case and effective prevention and control measures, the epidemics had no longer significant correlations among areas from March 5 to April 8. The study results showed relationship with time points of start and adjustment of emergency response at different degree in provinces. Furthermore, improving the early detection of new outbreaks and taking timely and effective prevention and control measures played an important role in blocking the transmission.

During the implementation of ecological protection in the Yellow River basin, understanding the water pollution status and spatio-temporal variation of water quality has become the most important thing for water safety in the basin. To analyze the water quality in recent years, the water quality data in the Yellow River basin from 2004 to 2018 were firstly collected from eight typical monitoring stations. Using a combination of multivariate data analysis methods including the Mann-Kendall (M-K) trend test, hierarchical clustering analysis (HCA), principal component analysis (PCA), and modified comprehensive water quality identification index (WQI), the spatio-temporal variation characteristics of the water quality were then explored in the Yellow River basin. The results indicated that in terms of time variation, the HCA from the water quality time series showed that the water quality of the Yellow River basin could be divided into the wet season, normal season, and dry season, being basically consistent with the hydrological period. Combined with the M-K trend test and WQI-based water quality assessment, the water quality of the Yellow River basin was improving gradually, with 2010 as the critical year. The water quality in the wet season was superior to that in the dry season. The pollution indicator NH 4 + -N and permanganate index were dominant in both the wet season and dry season. According to the spatial variation analysis, the water quality for all the studied stations improved significantly. Spatial clustering showed that the S6 (Shanxi Yuncheng Hejin Bridge) was obviously different from others, and further comparative study demonstrated that S6 was constantly seriously polluted. The S7 (Henan Jiyuan Xiaolangdi) exhibited different characteristics in the wet and dry season. In all stations, NH 4 + -N was considered to be the most common pollution indicator, whereas the permanganate index and DO were also relatively serious for S6. In different hydrological seasons, NH 4 + -N and the permanganate index showed different characteristics, and their variety was related to the fact that the former mainly came from domestic and industrial sources, whereas the latter was mainly derived from agricultural sources. The modified WQI showed obvious advantages over single-factor water quality assessment, and the findings from this study can provide scientific evidence for water pollution control and comprehensive water quality management in the Yellow River basin.

The NDVI (normalized difference vegetation index) was used as the vegetation coverage index. Based on the NDVI and weather data from 2000 to 2020, the characteristics of the spatiotemporal evolution and the driving mechanism of vegetation were investigated by using correlation analysis, the Theil-Sen estimator, the Mann-Kendall method, and multivariate residual trend analysis. The results showed that the growing season average NDVI in the Yellow River basin was a fluctuating upward trend of 0.005 a -1 from 2000 to 2020. Areas with significantly improved vegetation in the basin were mainly distributed in the Qinling Mountains, the Northern Shaanxi Plateau, and the Lvliang Mountains in the midstream. The average value of the partial correlation coefficient between the growing season average NDVI and rainfall in the Yellow River basin was 0.57, and the average value of the partial correlation coefficient between the growing season average NDVI and temperature was 0.49. The impact of rainfall on vegetation was higher than that of temperature. The areas where human activities significantly improved vegetation growth were mainly distributed in the northern Shaanxi Plateau, the Lvliang Mountains, and southern Ningxia. The areas where human activities inhibited vegetation growth were mainly distributed in cities with strong human activities such as Yinchuan, Baotou, Xi'an, Luoyang, Zhengzhou, and Taiyuan. Human activities and climate change contributed to 72% and 28% of the vegetation change in the Yellow River basin. Driven by human activities and climate change, the area where vegetation growth has improved in the Yellow River basin accounted for 96.4% of the basin area, of which the contribution rate of human activities greater than 80% of the area accounted for 34.3%, which was mainly distributed in the middle and southeast of the basin. The area with a contribution rate of climate change greater than 80% accounted for 4.2%, which was mainly distributed in the Sichuan-Tibet Plateau and Longzhong Loess Plateau in the basin. The results of this research can provide scientific support for the ecological protection and high-quality development of the Yellow River basin.

Objectives: To investigate the epidemic situation of hand-foot-mouth disease (HFMD) in Hunan Province, China, from 2008 to 2019, as well as its spatial autocorrelation characteristics and spatial-temporal clustering, and to provide a reference for the prevention and control of HFMD in Hunan Province., Methods: Spatial autocorrelation and spatial-temporal clustering analyses were used to analyze the monitoring data of HFMD in Hunan Province from 2008 to 2019., Results: The epidemic situation of HFMD in Hunan Province from 2008 to 2019 showed obvious seasonal distribution, with a low incidence rate in January to March and a high incidence rate in April to July. As for population distribution, children aged 0-5 years had the highest number of HFMD cases and accounted for 95.89% (1 460 391/1 522 910) of all cases, with a mean annual incidence rate of 2 197.784/100 000, and scattered children had the highest number of cases and accounted for 82.59% (1 257 739/1 522 910) of all cases. The global spatial autocorrelation analysis showed that the onset of HFMD in Hunan Province showed a significant clustering distribution, and the local spatial autocorrelation analysis showed that the high clustering areas of HFMD were mainly the districts and counties of Changsha, Zhuzhou, and Yueyang cities. Time-space scanning showed that clustering time was mainly April to July; the cases were clustered in the northeast of Hunan Province from 2008 to 2010 and in the central part of Hunan Province from 2011 to 2019., Conclusions: The high incidence rate of HFMD is observed in April to July in Hunan Province. Children under 5 years of age are at a high risk of this disease. Spatial-temporal clustering is observed for the epidemic of HFMD, mainly clustered in the northeastern and central areas of Hunan Province. It is suggested that the results may be used as guidance to determine the key areas for HFMD prevention and control in Hunan Province and optimize the allocation of health resources.

Objective: To understand the spatiotemporal distribution of pulmonary tuberculosis (TB) and influencing factors in Beijing from 2008 to 2018. Methods: The incidence data of pulmonary TB in Beijing from 2008 to 2018 were from Tuberculosis Information Management System of Chinese Disease Prevention and Control Information System. Software ArcGIS 10.2 was used to visualize the spatiotemporal distribution of pulmonary TB incidence. Getis's G i * statistic was applied to analyze the spatial clustering of pulmonary TB incidence at street/township scale. Bayesian spatiotemporal model was applied to analyze factors affecting its spatiotemporal distribution, including urbanization rate, GDP per capita, number of hospital beds per thousand population, permanent migrant population and population density. Results: The reported pulmonary TB incidence showed a downward trend in the past 11 years in Beijing, from 58.64/100 000 to 30.43/100 000. The incidences were higher in Tongzhou, Changping and other newly developed urban districts, with the hot spots concentrated in local areas of these districts. The incidences of pulmonary TB were lower in Dongcheng, Xicheng and other old urban districts-with the cold spots also concentrated in these area. The risk for the incidence of pulmonary TB was associated with the urbanization rate and the permanent migrant population. For every 1% increase in the urbanization rate, the relative risk of pulmonary TB would increase by 1%. For every 10 000 person increase of permanent migrant population, the relative risk of pulmonary TB would increase by 0.6%. Conclusions: In Beijing, the current pulmonary TB prevention and control needs to be focused on the newly developed urban areas. Due to the accelerated process of urbanization, it is necessary to strengthen TB prevention and control in permanent migrant population to reduce the incidence of TB in Beijing.

Objective: To understand the spatial-temporal distribution and spatial clusters of measles cases in China. Methods: Measles incidence data was collected from the National Notifiable Disease Reporting System of Chinese Center for Disease Control and Prevention. The global and local spatial autocorrelation analyses were conducted by using software ArcGIS 10.2 and spatial-temporal scan was conducted by using software SaTScan 9.6. Results: A total of 1 012 537 cases of measles were reported in China from 2001 to 2016 and the annual incidence showed a sharp downward trend. There was global spatial clustering of measles cases during 2001-2004, 2005-2008, and 2009-2012, and their Moran's I coefficients were 0.29, 0.26, and 0.31, respectively. The results of local spatial autocorrelation analysis showed that there were high- high clustering areas of measles at all time periods, especially in western China. Guangdong province was detected as a separate high-low scattered area from 2005 to 2008 and no low-low clustering area was detected. The spatial-temporal scan statistics showed that there was a wide clustering area covering western, central and northern China, and Shanxi province and Guangxi Zhuang Autonomous Region from 2001-2008. Conclusion: The incidence of measles in China has a certain clustering in both space and time during 2001-2016, the results provide evidence for the development of future strategy of measles prevention and control in China.

Objective: To analyze the epidemic characteristics and spatio-temporal distribution of hemorrhagic fever with renal syndrome (HFRS) in Guangzhou from 2010 to 2019 and provide a basis for prevention and control strategies. Methods: The data of HFRS was from National Disease Reporting Information System and the epidemic investigation. A descriptive analysis was used. OpenGeoDa 1.2.0 software was used for global spatial autocorrelation and local spatial autocorrelation analysis. SatScan 9.6 software was used for detecting the hot spot area in time and space. ArcGIS 10.2 software was used for map visualization. Results: 1 298 cases of HFRS were reported, and three patients died in Guangzhou in 2010-2019. The annual incidence rate was 0.99/100 000. The proportion of 21-50 years old cases accounted for 70.88% and the male to female ratio was 2.98∶1. Most patients were house workers or unemployed, accounting for 31.28%, followed by business servants (accounting for 17.33%). The incidence peak in spring and winter accounted for 33.74% and 26.35% of the year. All districts reported cases in recent ten years. A total of 407 cases had been reported in Haizhu district, accounting for 31.36% of the total number of cases in the whole city. The annual incidence rate was 2.52/100 000. The number of reported cases and the annual incidence rate were the highest in Guangzhou. The clustered area showed that there was spatio-temporal clustering in Guangzhou. The aggregation area was mainly concentrated in the urban villages adjacent to Wan-mu orchard and the Haizhu Lake Wetland Park in Haizhu district (logarithmic likelihood ratio was 44.08, P <0.001). Conclusions: The prevalence and concentration of HFRS in winter and spring Guangzhou city from 2010 to 2019, showed a high incidence. Young and middle-aged men engaged in domestic and unemployed, and commercial services appeared the main risk groups. The urban-rural junction with many immigrants and low health environment, streets adjacent to Wan-mu orchard, and the Haizhu Lake Wetland Park in Haizhu district were the important regions for preventing and controlling HFRS. The government should formulate prevention and control measures to curb the rise and spread of the HFRS epidemic.

Objective: To explore the spatio-temporal patterns and epidemic characteristics of imported dengue fever cases in six provinces (Yunnan, Guangxi, Guangdong, Hainan, Fujian and Zhejiang) of China from 2016 to 2018. Methods: In this study, we collected the surveillance data of imported dengue fever cases from 2016 to 2018 in six southern provinces of China. The risk intensity, spatio-temporal distribution and epidemiological characteristics of imported dengue fever cases in the six provinces were analyzed from the perspective of space, time and population. Results: Among the imported cases of dengue fever in China from other countries in the world, most of them were from Southeast Asia. In Zhejiang, Fujian and Guangdong provinces, there were greater number of imported cases with wide range of sources. While in Yunnan, Guangxi and Hainan provinces, the imported cases were almost from Southeast Asia. The incidence of imported dengue fever increased during the past three years, and the annual incidence peak was during August-November, but slight differences were observed among provinces. The age of the imported cases in Hainan[(37.0±19.6) years] was higher than that in southeastern coastal provinces[(36.0±11.7) years] and in southwestern provinces[(32.0±16.3) years]. The male-female ratio of the cases in southeastern coastal provinces (2.18∶1) were higher than those in southwestern provinces (1.04∶1) and Hainan (1.38∶1). The occupations of the cases were mainly workers and unemployed people in southeastern coastal provinces and farmers in southwestern provinces, but commercial personnel was the population with high incidence in both southeastern and southwestern provinces. Less imported dengue fever cases were reported in Hainan, the population distribution varied. Conclusions: There were differences in incidence pattern of imported dengue fever between southeastern coastal provinces and southwestern provinces as well as Hainan in China. Different prevention and control measures should be carried out in different areas to implement more precise prevention strategies.

Objective: To investigate the spatio-temporal distribution characteristics of Oncomelania hupensis snail habitats in three cities of Suzhou, Wuxi and Changzhou along the Taihu Lake region, so as to provide technical supports for establishing a sensitive and highly effective surveillance and forecast system for schistosomiasis., Methods: Snail distribution data were collected from Suzhou, Wuxi and Changzhou cities from 1950 to 2018, and the changing trend for snail habitats were described over years. In addition, the clusters of snail habitats were detected using Kernel density analysis and SaTScan space-time scan analysis., Results: The number of snail habitats appeared a single-peak distribution in Suzhou, Wuxi and Changzhou cities from 1950 to 2018, which peaked in 1970 and then declined rapidly. There were 62.68% of snail habitats eliminated within 10 years after identification, of which 38.24% were eliminated at the year of identification. Kernel density analysis and SaTScan space-time scan analysis revealed that high-density clusters of snail habitats were mainly distributed in Kunshan City, Wuzhong District and Xiangcheng District from 1970 to 1980, and in Yixing City in 1990; since then, the clusters gradually shrank, and overall appeared a move from northeast to west of Taihu Lake. A total of 4 new clusters were detected after 1970, as revealed by space-time scanning of snail habitats. In current snail habitats, emerging snail habitats are mainly identified in Huqiu District (Dongzhu Town), Wuzhong District (Guangfu Town), Taicang City (Shaxi Town) and Jintan District, and re-emerging snail habitats are scattered in 7 districts., Conclusions: The distribution of snail habitats are spatio-temporal aggregation in Suzhou, Wuxi and Changzhou cities. The monitoring and prediction of emerging and re-emerging snail habitats are the key points in the future.

Hemorrhagic fever with renal syndrome (HFRS) is a rodent-borne disease of natural infectious focus caused by Hantavirus (HV) with clinical characteristics as fever, hemorrhage, hyperemia, hypotensive shock and renal damage. Through contacting the excreta or secretion of infected rats, human may get infected. The epidemiological characteristics of HFRS are significantly different in terms of population differences, geographical heterogeneity and seasonal variation, which are all closely related to the habitat of host animals and human productive activities. The reported number of HFRS is about 150 000 to 200 000 each year worldwide, and China accounted for 70 % -90 % of the total reported cases standing the most seriously infected country. In this study, we reviewed the epidemiological characteristics and the influencing factors of HFRS as well as the models and methods used in relevant ecological studies, in order to understand the distribution of time, regional and population and potential influencing factors on the transmission of HFRS better, so as to improve the strategies on investigation, monitoring, prevention and control of the diseases.

Carrying out research on infectious epidemics is an important work contents stipulated in the Law on the Prevention and Control of Infectious Diseases in China. Nowadays, Based on the recent Chinese prevention and treatment system of infectious eye diseases, it is difficult to meet the needs of data collection, etiology determination, and spatiotemporal analysis. The present article explores how to use modern social epidemiology methods to clarify the role of individual factors, social factors, and structural factors in the three links of eye disease epidemic, how to use spatial epidemiology methods to describe, quantify, and explain the spatial distribution characteristics of eye diseases in the population, and how to use infodemiology and digital epidemiology methods to promptly and efficiently mine and process massive amounts of electronic data of eye diseases. These may be used to improve the scientific nature of Chinese eye disease epidemiology research, and strengthen the China's infectious eye disease prevention and control system. (Chin J Ophthalmol, 2020, 56:567-570) .

Objective: To understand the characteristics of spatiotemporal clustering on hepatitis A in Gansu province and to provide evidence for hepatitis A prevention and control. Methods: Data related to hepatitis A were retrieved from National Notifiable Disease Report System, ArcGIS 10.3 and SaTScan 9.1 in Gansu province from 2004 to 2018. Results: The annual average report incidence rate of hepatitis A was 10.91/100 000, showing a descending trend with no periodic or seasonal features. After the implementation of national expanded immunization program, high annual incidence rates had been seen in Linxia Hui autonomous prefecture and Gannan Tibetan autonomous prefecture. From 2004 to 2012, the lowest RR value appeared in the 0-9 age group ( P =0.000) while the highest RR value was in the over 60 age group during 2013-2018 except for the age 0-9 group in 2015. The annual average incidence rate was increasing from south to north and west to east, across the territory. Results from the temporal scanning program revealed that the incidence of hepatitis A was temporally aggregated from 2004 to 2018. For spatio-temporal scanning of 2004-2008, data showed one most likely cluster area (radius: 91.95 km, Time frame: 2004-2005), apparel mainly in Linxia and Longnan cities. Results from the spatio-temporal scanning program of 2009-2018 also showed that the most likely cluster areas (radius: 183.26 km, Time frame: 2009-2012) were in Gannan, Linxia, Dingxi and Longnan areas. Conclusions: The reported incidence rates of hepatitis A were declining, without significant periodic or seasonal pattern in Gansu province from 2004 to 2018. In the 0-9 years-old group, the incidence rate showed the lowest, while the highest was in the 60 year-olds group. Spatio-temporal clustering of hepatitis A was observed in Gansu province from 2004 to 2018. Strategies on prevention and control of the disease should be targeted in the southwest regions of the province.

In recent years, the research of spatiotemporal clustering of disease is attracting more and more attention, which plays an important role in understanding the temporal and spatial distribution characteristics of diseases, and can provide references for the etiology exploration and prevention and control of diseases. In order to better understand the research methods of spatiotemporal clustering of diseases and its application progress, this paper summarizes the statistical methods commonly used in relevant researches at demestic and abroad from three aspects of temporal clustering, spatial clustering and spatiotemporal clustering of diseases.

Objective: To analyze the spatial-temporal distribution characteristics of human brucellosis (HB) in Ningxia Hui Autonomous Region (Ningxia) from 2012 to 2018 and the correlation between HB and the number of livestock stocks, so as to provide reference for the development of preventive measures. Methods: Data on the incidence of HB was collected from the Infectious Disease Report Information Management System of Ningxia, 2012 to 2018. Data related to HB incidence in Ningxia from 2012 to 2018 was then analyzed by global spatial autocorrelation and local spatial autocorrelation analysis methods through the geographic information system (GIS). SPSS (23.0) Spearman correlation was used to analyze the correlation between the incidence of HB and the number of cattle, sheep and pigs. Results: From 2012 to 2018, the incidence of HB showed an overall increase in Ningxia, with an annual growth in 2012-2015 but declined between 2015 and 2018. Results from the global autocorrelation analysis showed that the distribution of HB in the counties and districts of Ningxia appeared non-randomly, with Moran's I value as positive in 2012, 2013 and 2016 indicating the distribution was positive in space. Through local autocorrelation analysis, results showed that "H-H" concentration area was mainly concentrated in central while the "L-L" concentration area was mainly in the northern part of Ningxia. As for the results from correlation analysis between HB and animal husbandry, it showed that the incidence of HB was positively correlated with the number of sheep in stock ( r =0.692, P =0.000). Conclusions: The epidemic situation of HB expressed different degrees of aggregation. Areas with high incidence were mostly concentrated in central Ningxia, and with certain degree of correlation with the number of sheep in stock. Corresponding measures should be taken to control the different aggregation situation. Programs on quarantine and immunization for sheep should also be strengthened.

We used the epidemic data of COVID-19 published on the official website of the municipal health commissions in Anhui province to map the spatiotemporal changes of confirmed cases, fit the epidemic situation by the population growth curve at different stages and analyze the epidemic situation in Anhui Province. It was found that the cumulative incidence of COVID-19 was 156/100 000 by February 18, 2020 and the trend of COVID-19 epidemic declined after February 7 with a change from J-shaped curve to S-shaped curve. As the reporting time of cases might be 3-5 days later than the actual onset time, the number of new cases in Anhui province actually began to decline around February 2 to February 4, 2020.