Search Results (56)

The inter-provincial border region in eastern China, encompassing the junction of Jiangsu, Anhui, Shandong, and Henan provinces, serves as a crucial zone that connects the important economic zones of Beijing–Tianjin–Hebei and the Yangtze River Delta. It is of great significance to study the temporal variation characteristics, spatial distribution patterns, and driving factors of PM_2.5 concentrations in this region. Based on the PM_2.5 concentration observation data, ground meteorological data, environmental data, and socio-economic data from 2022 to 2024, this study conducted in-depth and systematic research by using advanced methods, such as spatial autocorrelation analysis and geographical detectors. The research results show that the concentration of PM_2.5 rose from 2022 to 2023, but decreased from 2023 to 2024. From the perspective of seasonal variations, the concentration of PM_2.5 shows a distinct characteristic of being “high in winter and low in summer”. The monthly variation shows a “U”-shaped distribution pattern. In terms of spatial changes, the PM_2.5 concentration in the inter-provincial border region of eastern China (Jiangsu, Anhui, Shandong, Henan) forms a gradient difference of “higher in the west and lower in the east”. The high-concentration agglomeration areas are mainly concentrated in the Henan part of the study region, while the low-concentration agglomeration areas are distributed in the eastern coastal parts of the study region. The analysis of the driving factors of the PM_2.5 concentration based on geographical detectors reveals that the average temperature is the main factor affecting the PM_2.5 concentration. The interaction among the factors contributing to the spatial differentiation of the PM_2.5 concentration is very obvious. Temperature and population density (q = 0.92), temperature and precipitation (q = 0.95), slope and precipitation (q = 0.97), as well as DEM and population density (q = 0.96), are the main combinations of factors that have continuously affected the spatial differentiation of the PM_2.5 concentration for many years. The research results from this study provide a scientific basis and decision support for the prevention, control, and governance of PM_2.5 pollution. Full article

To investigate the distribution of hantavirus (HV) in rodent organs, we selected eight counties across four regions in Hebei Province (southern, northern, eastern, and central) as study areas. Rodents were captured using night trapping methods, and organ samples were aseptically collected for HV detection via quantitative real-time PCR (qPCR) and gene sequencing. During the 2022–2023 spring and autumn seasons, 1386 rodents were trapped, including 73 Rattus norvegicus carrying Seoul virus (SEOV). The highest detection rate was observed in the liver (3.84%), followed by the kidneys (3.46%) and lungs (3.09%). Viral load analysis revealed higher SEOV RNA levels in the liver than in the lungs and kidneys. Antibody levels in R. norvegicus may influence the detection of viruses in organs. Phylogenetic analysis indicated that all sequences belonged to the S3 subtype, exhibiting regional aggregation and genetic stability. Our findings emphasize the necessity of multi-organ sampling for comprehensive HV surveillance and epidemic risk assessment. Full article

In recent years, surface ozone (O₃) pollution has emerged as a significant barrier to the continued improvement of air quality in China, making O₃ risk assessment a critical research priority. Using nationwide O₃ monitoring data, this research investigated the spatial characteristics of O₃ pollution and assessed its potential impacts on human health and crop yields. The results showed that the maximum daily 8 h average O₃ (MDA8 O₃) exhibited higher concentrations in eastern and northern regions, and lower concentrations in the western and southern regions of China. Long-term O₃ exposure was associated with an estimated 175,154 all-cause deaths nationwide, with the highest health risks observed in Shandong, Henan, and Jiangsu provinces. The AOT40 values for the winter wheat and single-rice growing seasons in China were 9.30 × 10³ ppb·h and 1.29 × 10⁴ ppb·h, respectively. Moreover, O₃ exposure led to relative yield losses of 22.1% for winter wheat and 9.3% for single rice, corresponding to crop yield losses (CPLs) of 63 million metric tons and 14 million metric tons, respectively. Higher winter wheat CPL values were primarily concentrated in Henan, Shandong, and Hebei, while higher single rice CPL values were observed in Jiangsu, Hubei, and Anhui. This study presents a novel coupling of O₃ pollution exposure with human health and agricultural risk assessments across China, emphasizing the need for region-specific O₃ management strategies to protect public health and ensure agricultural sustainability. In conclusion, this study highlights the importance of targeted O₃ control in densely populated and major crop-producing areas to mitigate health risks and yield losses, thus safeguarding ecosystem health and food security. Full article

Urbanization has greatly altered Earth’s surface form, and land use changes can lead to significant changes in carbon emissions. However, how these changes affect ecosystems remains unclear. Therefore, this study calculated the carbon absorption and emissions in 31 Chinese provinces using high-resolution (300 m) land use data. Subsequently, a carbon flow model was used to evaluate the carbon transfer that occurred from the changes in land use in every province between 2000 and 2020. The standard deviation ellipse analytic techniques were also employed to research the spatiotemporal evolution features of carbon flow in various economic zones. Furthermore, the flux and utility analysis approaches in ecological network analysis were used to quantitatively examine the interaction relationship between two carbon metabolism land uses. The results revealed that the continuous expansion of China’s construction land has reduced the area of agricultural land, resulting in industrial land (53.14%) and urban land (39.38%) being the main contributors to the total carbon emissions. Among them, the five eastern provinces of Hebei, Jiangsu, Zhejiang, Shandong, and Guangdong had carbon emissions of more than 100 million tons. From 2000 to 2020, the center of gravity of the carbon flow in construction land had shifted significantly from Henan Province to Gansu Province. The ecological relationship of exploitation and control dominated the two land use types. It is mostly found in Xinjiang, Qinghai, Gansu, Inner Mongolia, and Ningxia provinces. The findings could provide relevant policy implications for the Chinese government to mitigate carbon metabolism on land. Full article

The COVID-19 pandemic has profoundly impacted the tourism industry, particularly red tourism. This study investigates the spatiotemporal characteristics and dynamics of population flow in red tourism counties during the pre-pandemic and post-pandemic periods, aiming to provide valuable insights for sustainable red tourism planning and policy formulation. This study covers 180 red tourism counties across 20 provinces in China, utilizing mobile signaling data from May and October of 2018, 2020, 2022, and 2023. The results show that, in 2023, the total population inflow to red tourism counties reached 4448.85 × 10⁴, with a notable spatial disparity, mainly concentrated in northern and central regions, such as Beijing, Linyi, and Liu’an. The inflow was primarily from eastern and central provinces, such as Guangdong, Hebei, and Henan, with these areas showing substantially higher visitation than western and northeastern regions. These inflows were strongly influenced by geographic proximity and transportation accessibility, with a significant increase during holiday periods reflecting the role of tourism policies in shaping mobility patterns. From 2018 to 2023, population dynamics fluctuated significantly due to the pandemic, with a strong recovery by 2023, surpassing pre-pandemic levels by 1332.26 × 10⁴. The recovery rates varied regionally, with areas such as Inner Mongolia and Qinghai showing substantial growth, while provinces such as Beijing and Shanxi showed slower recovery. These findings underscore the enduring appeal of red tourism and highlight the effectiveness of targeted policy interventions. However, regional disparities in recovery rates suggest that focused efforts are needed to ensure balanced and sustainable red tourism development. Full article

Coccidiosis is one of the most significant diseases affecting the rabbit industry and is caused by Eimeria. In a previous study, we identified a new species of Eimeria kongi (E. kongi-ZJK) from the northern region of China (Zhangjiakou, Hebei Province) and studied its pathogenicity and immunogenicity. The aim of this study was to evaluate the pathogenicity, immunogenicity, and cross-immunogenicity from different geographical isolates of E. kongi for vaccine development. Two geographical isolates of E. kongi-QD from Qingdao, Shandong Province (eastern China), and E. kongi-CD from Chengdu, Sichuan Province (southwestern China), were isolated and identified. The pathogenicity, immunogenicity, and cross-immunogenicity among the three geographical isolates were evaluated. The pathogenicity results showed that after infecting rabbits with doses of 1 × 10³ or fewer sporulated oocysts of E. kongi-QD and E. kongi-CD, the rabbits exhibited clinical symptoms but recovered quickly, indicating lower pathogenicity. Immunogenicity studies revealed that after immunizing rabbits with 1 × 10³ sporulated oocysts of E. kongi-QD and E. kongi-CD for 14 days, followed by challenge with 1 × 10⁴ homologous sporulated oocysts, the oocyst reduction rates in the immunized groups were 99.39% and 99.12%, respectively, compared with the non-immunized groups, demonstrating good immunogenicity. In cross-immunogenicity studies, rabbits were immunized with 1 × 10³ sporulated oocysts of E. kongi-ZJK, E. kongi-QD, or E. kongi-CD and then challenged with 1 × 10⁴ sporulated oocysts of heterologous isolate. The immunized groups showed no significant clinical symptoms, and the oocyst reduction rates ranged from 55.9% to 98.4%. E. kongi-CD exhibited cross-protection against E. kongi-ZJK and E. kongi-QD, making it an ideal candidate formulation for vaccine development. Full article

In recent years, tourism and leisure districts have become a pivotal aspect of China’s tourism development. Analyzing their spatial distribution characteristics and driving factors is essential for fostering comprehensive district tourism and promoting sustainable development, while also facilitating the profound integration of culture and tourism. This study undertakes a thorough investigation of the spatiotemporal patterns of national-level tourism and leisure districts in China, employing GIS spatial statistical analysis techniques, including the Average Nearest-Neighbor Index, Kernel Density Analysis, and Standard Deviation Ellipse. Additionally, this research identifies the principal driving factors affecting the spatial distribution of these districts through overlay analysis, buffer analysis, and geographic detectors. The findings reveal that (1) tourism and leisure districts exhibit a notable spatial clustering pattern, characterized by a predominance in the eastern regions and scarcity in the west, alongside a higher concentration in the south compared to the north, with a gradual decline in spatial density. (2) High-density tourism and leisure districts are predominantly located in the Yangtze River Delta and the Beijing–Tianjin–Hebei urban agglomerations, while regions of elevated density are situated in the southwest (notably in Sichuan, Chongqing, Guizhou, and Yunnan provinces). The centroids of the first to third batches of tourism and leisure districts have transitioned from southern to northern locations. (3) The population density factor exhibits the most substantial explanatory power regarding the distribution of tourism and leisure districts (q: 0.80528), followed by the added value of the tertiary industry (q: 0.53285), whereas the slope factor shows minimal influence (q: 0.00876). Furthermore, the distance to rivers of grade three and above, in conjunction with population density, constitutes the primary factor combination influencing the spatial configuration of tourism and leisure districts (q: 0.9101). Full article

It is widely recognized that the phenology of insects, of which the life activities are closely tied to temperature, is shifting in response to global climate warming. This study aimed to investigate the impacts of climate change on the phenology of Carposina sasakii Matsumura, 1900 (Lepidoptera: Carposinidae) across large temporal and spatial scales, through collecting and systematically analyzing historical data on the pest’s occurrence and population dynamics in China. The results showed that for overwintering adults, the first occurrence date in eastern, northwestern, and northern China has significantly advanced, along with the population peak in eastern and northwestern China. At the provincial level, the population peak date in Shandong province has also moved significantly earlier, as well as the population peak date in Shandong and Shaanxi and the end occurrence date in Ningxia. However, the population peak date in Jilin has experienced a delayed trend. For first-generation adults, the first occurrence date in northeastern, eastern, and central China has notably advanced, while the first appearance date in northwestern and northern China has significantly delayed. Additionally, the population peak in northwestern China has experienced significant delays, along with the final occurrence in northeastern and northwestern China. At the provincial level, the first occurrence date in Liaoning, Shandong, and Shanxi has significantly advanced, while Hebei has demonstrated a significant delay. The population peak time in Gansu and Shaanxi has displayed significant delays, and the end occurrence date in Liaoning, Shanxi, and Shaanxi has also shown significant delays. Furthermore, these findings integrated with the Pearson correlation results reveal spatial heterogeneity in C. sasakii’s phenological responses to climate warming at both regional and provincial scales. The phenology of C. sasakii and their changing patterns with climate warming vary by geographical location. This study provides valuable information for the future monitoring, prediction, and prevention of peach fruit moths in the context of climate warming. Full article

A perennial leguminous forage, Medicago ruthenica has outstanding tolerance to abiotic stresses. The genome of Medicago ruthenica is large and has a complex genetic background, making it challenging to accurately determine genetic information. However, the chloroplast genome is widely used for researching issues related to evolution, genetic diversity, and other studies. To better understand its chloroplast characteristics and adaptive evolution, chloroplast genomes of 61 Medicago ruthenica were assembled (including 16 cultivated Medicago ruthenica germplasm and 45 wild Medicago ruthenica germplasm). These were used to construct the pan-chloroplast genome of Medicago ruthenica, and the chloroplast genomes of cultivated and wild Medicago ruthenica were compared and analyzed. Phylogenetic and haplotype analyses revealed two main clades of 61 Medicago ruthenica germplasm chloroplast genomes, distributed in eastern and western regions. Meanwhile, based on chloroplast variation information, 61 Medicago ruthenica germplasm can be divided into three genetic groups. Unlike the phylogenetic tree constructed from the chloroplast genome, a new intermediate group has been identified, mainly consisting of samples from the eastern region of Inner Mongolia, Shanxi Province, and Hebei Province. Transcriptomic analysis showed that 29 genes were upregulated and three genes were downregulated. The analysis of these genes mainly focuses on enhancing plant resilience and adapting adversity by stabilizing the photosystem structure and promoting protein synthesis. Additionally, in the analysis of adaptive evolution, the accD, clpP and ycf1 genes showed higher average Ka/Ks ratios and exhibited significant nucleotide diversity, indicating that these genes are strongly positively selected. The editing efficiency of the ycf1 and clpP genes significantly increases under abiotic stress, which may positively contribute to plant adaptation to the environment. In conclusion, the construction and comparative analysis of the complete chloroplast genomes of 61 Medicago ruthenica germplasm from different regions not only revealed new insights into the genetic variation and phylogenetic relationships of Medicago ruthenica germplasm, but also highlighted the importance of chloroplast transcriptome analysis in elucidating the model of chloroplast responses to abiotic stress. These provide valuable information for further research on the adaptive evolution of Medicago ruthenica. Full article

The northern margin of the North China Craton is one of the most important porphyry-skarn molybdenum ore belts in the world. The eastern Hebei Province, which contains a high number of molybdenum and gold (molybdenum) resources, is an important portion of the northern margin of the North China Craton. Xichanggou and Huashi, located in eastern Hebei, are quartz-molybdenum vein deposits that are intimately associated with intrusions that are deeply concealed in the mining area. This work presents two zircon U-Pb dates and ten molybdenite Re-Os ages from samples of the aforementioned two deposits in order to determine the timing of the intrusion and mineralization. The zircon U-Pb ages of the quartz monzonite porphyry from Xichanggou are determined to be 163.3 ± 0.3 Ma and 162.8 ± 0.4 Ma. The molybdenite Re-Os dating yielded ages of 160.3 ± 4.6 Ma for Xichanggou and 171.4 ± 19 Ma for Huashi, respectively. The isotopic composition of oxygen and hydrogen of the ore-forming fluid from Huashi, as indicated by the δD_V-SMOW values (−80.0‰ to −67.6‰) and δ¹⁸O_H2O values (−1.86‰ to 2.33‰), suggests that the fluid is primarily composed of water derived from magma, with some contribution from atmospheric precipitation. The sulfur isotope values (δ³⁴S) of sulfides from Xichanggou range from 6.5‰ to 7.1‰, while the δ³⁴S values from Huashi range from 3.3‰ to 4.9‰. The lead isotope ratios (²⁰⁶Pb/²⁰⁴Pb and ²⁰⁷Pb/²⁰⁴Pb) of sulfides from Xichanggou and Huashi average at 17.414, 15.428, and 17.591, 15.379, respectively. The Re-Os isotopic compositions of ore sulfides mostly fall within the range of 318 ppm to 50,114 ppm. These isotopic compositions indicate that the materials responsible for the formation of the ores in Xichanggou and Huashi primarily originate from the melting of lower crust materials that have been contaminated by the mantle. Based on the regional data, the molybdenum deposits in eastern Hebei were formed in multiple periods, specifically approximately 170 Ma and 160 Ma in Huahsi and Xichanggou, respectively. The subduction of the Paleo-Pacific plate during the middle–late Jurassic period led to the partial remelting of lower crust material, resulting in the acquisition of a significant quantity of metal elements (Mo), which were subsequently deposited. Full article

As a frequent hazard, tropical cyclones have a great impact on the social and economic development of China, which is close to the origin of tropical cyclones in the western Pacific Ocean. The primary objective of this study was to construct a comprehensive risk assessment model for tropical cyclone hazards based on natural influencing factors, informing recommendations for hazard prevention and mitigation in affected regions. This research focused on tropical cyclones that made landfall in mainland China and Hainan from 1949 to 2023, utilizing hazard risk theory and classical extreme value theory. The wind speed and rainfall data during the peak cyclone periods (June to October) from 1997 to 2021 gathered from various meteorological stations, as well as altitude and vegetation cover data, were examined. Hierarchical analysis and ArcGIS spatial analysis methods were employed to study the characteristics of the spatiotemporal distribution of landfalling tropical cyclones and the comprehensive risk of tropical cyclone hazards, and the regions of China were delineated according to these methods. The results showed that, during the period from 1949 to 2023, the overall number of landfalling tropical cyclones decreased in a fluctuating manner, while the intensity of the cyclones increased. Furthermore, severe typhoons tended to occur more frequently in the summer than autumn with time, intensifying the challenge to resist short-term hazards. Moreover, the hazard-causing factors in areas affected by tropical cyclones displayed an increasing trend from north to south and from west to east. In detail, the regions sensitive to natural hazards were primarily located in the central part of Liaoning province, Tianjin, central and eastern Hebei province, Shandong province, eastern Henan province, central and northern Anhui province, Jiangsu province, and Shanghai, which are characterized by flat terrain and relatively low vegetation cover. Overall, the comprehensive risk of tropical cyclone hazards showed a geographical distribution that decreases from south to north and from east to west, with coastal cities in provinces such as Hainan, Guangdong, Guangxi, Fujian, and Zhejiang—including Haikou, Zhanjiang, Xiamen, Beihai, and Taizhou—exhibiting the highest levels of risk. Full article

In light of the tremendous pressure for improving urbanization levels and expanding construction land on ecosystems, regional sustainable development is premised on the coordinated development of the ecological environment and urbanization. This paper focuses on the Circum-Bohai-Sea Region and assesses the ecosystem service value (ESV) and urbanization level using the equivalence factor and entropy-weighted TOPSIS methods. Based on these assessments, it examines the coupling coordination between the ESV and urbanization as well as the obstacles to this coordination, utilizing the coupling coordination degree model, spatial autocorrelation model, and obstacle model. The results revealed several key findings. First, the Circum-Bohai-Sea Region experienced a continuous improvement in the urbanization level from 2005 to 2020, which presented a “center–periphery” spatial pattern. Overall, the ESV exhibited an N-shaped trend, namely, initially increasing, then decreasing, and then rapidly increasing. The ESV per unit of area exhibited a spatial difference, with the boundary of Baoding and Cangzhou as the dividing line. The ESV per unit of area in the northern parts was higher than that in the southern parts. Second, the degree of the coupling coordination between the ESV and urbanization exhibited an inverted U-shaped trend, initially increasing and then slightly decreasing. It also exhibited significant spatial heterogeneity, with the degree of the coupling coordination in the northern parts being higher than that in the southern parts and that in the central parts being higher than those in the eastern and western parts. Additionally, the ESV showed a significant spatially positive correlation with urbanization. H-H clusters were predominantly found in central and southern Liaoning Province, while L-L clusters were primarily located in southern Hebei Province and western Shandong Province. Third, the obstacle factors remained stable during the study period. The top five obstacles in the ESV system were the water resource supply, nutrient cycling maintenance, raw material production, aesthetic landscape, and food production. Moreover, the top five obstacles in the urbanization system were the number of college students per 10,000 people, population density, number of health technical personnel per 10,000 people, per capita road area, and proportion of secondary and tertiary industry output values. Full article

With the active promotion of the “carbon peaking and carbon neutrality” goals, science and technology finance (STF) is the important driving force of low-carbon development, and financial networks facilitate the aggregation and transformation of resources in space, so it is of great theoretical and practical significance to investigate the impact of science and technology finance networks (STFN) on carbon emissions (CE). Based on the 30 provinces of China from 2011 to 2019, this article used the STF development level in each province as the main indicator to construct the STFN. The complex network analysis and econometric models are combined, with the weighted degree values and betweenness centrality selected as typical network structure indicators incorporating into the econometric model to explore their impact on CE. Then, the Geographically and Temporally Weighted Regression (GTWR) model is applied to analyse the spatio-temporal heterogeneity of influencing factors. The results show the following: (1) From 2011 to 2019, the spatial structure of China’s STFN has changed significantly, and the status of the triangle structure consisting of Beijing–Tianjin–Hebei (BTH)–Yangtze River Delta (YRD)–Pearl River Delta (PRD) is gradually consolidated in the overall network, and the network structure tends to be stable. (2) The results of the benchmark regression show that the weighted degree value of the STFN has a significant inhibitory effect on CE, while betweenness centrality shows a certain positive effect on CE. (3) The weighted degree value has a more significant effect on CE reduction in the eastern region, while the betweenness centrality has a more significant effect on CE reduction in the central and western regions, but shows a significant promotion effect in the eastern region. (4) There is spatio-temporal heterogeneity in the effects of residents’ affluence, energy consumption, industrial structure, and environmental pollution on CE. Full article

The “2+26” cities are 26 cities in Beijing, Tianjin and the surrounding cities, constituting a region characterized by economic prosperity and diverse industries but plagued by severe atmospheric pollution. As a focal area for atmospheric pollution control, a scientific assessment of atmospheric environmental efficiency in the “2+26” cities that measures the degree of coordination between the economy and air pollution is very important for winning the battle of blue sky defense. Based on this, this study comprehensively used the nonradial multi-directional efficiency analysis (MEA) model, Global Reference Malmquist Model and spatial correlation analysis to evaluate the atmospheric environmental efficiency, calculate the driving factors and explore the spatiotemporal distribution characteristics of the “2+26” cities from 2009 to 2018. The research findings indicate the following: (1) Atmospheric environmental efficiency showed a trend of first decreasing and then increasing, with a significant improvement potential of 26.7% in the future. (2) There was a significant discrepancy between the best- and worst-performing cities, with the best being 0.910 and the worst being 0.573, demonstrating imbalanced development between cities. The relatively low-efficiency cities were mainly located in Hebei, Shanxi and Henan provinces. (3) A value of technological efficiency change (EC) less than 1 was the main restrictive factor for improving atmospheric environmental efficiency, whereas a value of technological change (TC) greater than 1 enhanced it. (4) The atmospheric environmental efficiency presented a distinct spatial distribution pattern of high–high and low–low aggregation, forming high-value areas centered in the Beijing–Tianjin region and along the Zibo–Zhengzhou line. The western and central regions were relatively low, whereas the northern and eastern regions were relatively high, with significant regional differences in spatial distribution. The conclusions from this article’s empirical analysis can help concerned developing countries determine key factors to improve their atmospheric environmental efficiency and then formulate policies for sustainable economic and environmental development. Full article

The longicorn beetle Monochamus saltuarius (Coleoptera; Cerambycidae) is an insect vector that transmits the pine wood nematode Bursaphelenchus xylophilus, a serious issue in pine forests in China, Japan, and South Korea. Dastarcus helophoroides and Scleroderma guani are effective in controlling M. saltuarius. However, the application of these parasites for the direct control of vector insects requires detailed analyses of the suitability of the selected natural enemies in potential pest areas, particularly under climate change. Based on species distribution records as well as the current and projected climate change trends up to 2050, we utilized an optimized Maxent algorithm to predict the potential distribution patterns of M. saltuarius and its natural enemies in China. Furthermore, we estimated Schoener’s D to quantify the overlap in adaptability between M. saltuarius and its natural enemies. The potentially suitable areas predicted under the current climate conditions were concentrated mainly in northeast and north China. Additional suitable areas were detected in central, eastern, northwestern, and southwestern China. Under future climate conditions, the suitable range of M. saltuarius gradually shifted southward, with a tendency to expand into high-altitude and colder regions, such as Sichuan, Qinghai, and Tibet. The potential distribution of the natural enemies D. helophoroides and S. guani continued to expand under climate change. A comparison of the appropriate habitats of M. saltuarius and natural enemy insects indicated that D. helophoroides is more suitable for initial biological control in north, northeast, and central China as well as certain northwest and coastal regions. S. guani could be prioritized for nationwide release, while joint control using both species may be effective in Liaoning, Hebei, and Tianjin provinces. These analyses demonstrate that future climate change is likely to exert adverse effects on the potential distribution of M. saltuarius but is favorable for the potential distributions of natural enemies. This study offers important insights into the effective control of M. saltuarius and provides an experimental basis for the utilization of natural enemies according to the characteristics of different regions. Full article