[Evaluation of Heavy Metal Distribution Characteristics and Ecological Risk of Soil of Vegetable Land for Hong Kong in Ningxia].

Heavy metal pollution in farmland soil can affect the growth, development, and yield of vegetable crops, as well as the quality and taste of vegetables, and can be continuously transmitted and enriched through the food chain, which ultimately poses a certain hazard to human health in the long term. Therefore, in order to investigate the distribution characteristics of soil heavy metals after years of multi-crop planting of vegetables supplied to Hong Kong, predict their ecological risks, and analyze the causes of pollution formation, 477 surface soil samples of vegetable fields supplied to Hong Kong in Ningxia were collected for three consecutive years from 2019 to 2021, and the contents and distribution characteristics of eight heavy metals, namely, As, Cd, Cr, Hg, Pb, Cu, Zn, and Ni were analyzed. The soil heavy metal pollution status of vegetable fields supplied to Hong Kong in Ningxia was evaluated using the single-factor pollution index method, Nemero's comprehensive pollution index method, land accumulation index method, and potential ecological risk index method, and the sources of heavy metals in vegetable fields supplied to Hong Kong in Ningxia were analyzed using the Pearson's correlation analysis and the principal component analysis method. The results showed that the mean values of As, Cd, Cr, Hg, Cu, and Zn in the soils of Ningxia's vegetable fields were higher than the background values of Ningxia soils, but the contents of all eight heavy metals were lower than the risk screening values of domestic agricultural soils; in terms of spatial distribution, As, Cr, and Ni showed contiguous high values in the northwestern, central, and southern parts of the study area, whereas Pb, Zn, Cd, Hg, and Cu showed high values in the northwestern and southern parts of the study area. The single-factor index method and the Nemero's comprehensive pollution index method showed that the soil of Ningxia's vegetable farmland for Hong Kong was at the clean level as a whole. The results of the ground accumulation index method showed that the pollution in the study area was mainly Hg and Cd pollution, and the pollution areas were mainly concentrated in the northwest and south of the study area. The potential ecological risk index showed that Hg and Cd were the main risk elements, among which Hg was dominated by moderate, strong, and very strong ecological risks, accounting for 44.65 %, 44.65 %, and 1.26 %, respectively, and Cd was dominated by moderate and strong risks, accounting for 65.83 % and 3.56 %. The comprehensive Pearson correlation analysis and principal component analysis showed that the pollution sources of eight heavy metals could be divided into three categories, namely, natural sources:Cu, Zn, Pb, As, Ni, and Cr; agricultural sources:Cd; and industrial and agricultural sources:Hg. From a comprehensive point of view, the heavy metals of the soil in the fields of vegetables supplied to Hong Kong had not exceeded the standard, and the environmental conditions of the soil were good, such that the production of vegetables supplied to Hong Kong by Ningxia was at a safe level overall. The results of the study can provide a theoretical basis for the safe utilization of soil in vegetable fields and the green production of vegetables supplied to Hong Kong in Ningxia, which were aimed to provide help for the safe production of vegetable fields supplied to Hong Kong, the rational application of fertilizers, agronomic planning, and the adjustment of planting structure.

Changes of soil nutrients and organic carbon fractions in Caragana korshinskii forests with different restoration years in mountainous areas of southern Ningxia, China.

Vegetation restoration can effectively enhance soil quality and soil organic carbon (SOC) sequestration. In this study, the distribution characteristics of soil nutrients and SOC along soil profile (0-100 cm), and their responses to restoration years (16, 28, 38 years) were studied in Caragana korshinskii plantations in the southern mountainous area of Ningxia, compared with cropland and natural grassland. The results showed that: 1) the contents of SOC, soil total nitrogen (TN), total phosphorus (TP), particulate organic carbon (POC), mineral-associated organic carbon (MAOC) and the proportion of particulate organic carbon to total organic carbon (POC/SOC) all decreased with increasing soil depth. The ratio of mineral-associated organic carbon to total organic carbon (MAOC/SOC) exhibited an opposite trend. 2) The contents of SOC, TN, TP, C:P, N:P, POC and MAOC gra-dually decreased as the restoration years increased. However, the C:N ratio showed no significant change. The POC/SOC ratio initially increased and then decreased, while the MAOC/SOC ratio decreased initially and then increased. 3) In three different types of vegetation, POC, MAOC, and SOC showed a highly significant positive linear correlation, with the increase in SOC mainly depended on the increase in MAOC. The SOC, TN, TP, POC and MAOC contents in natural grassland and C. korshinskii plantations were significantly higher than those in cropland. In conclusion, soil nutrients and POC and MAOC contents of C. korshinskii plantations gradually decreased with the increases in restoration years. However, when compared with cropland, natural grassland and C. korshinskii plantations demonstrated a greater capacity to maintain and enhance soil nutrient and carbon storage.

A study of the spatial network structure of ethnic regions in Northwest China based on multiple factor flows in the context of COVID-19: Evidence from Ningxia.

As an underdeveloped and low-income region, the development of minority regions in Northwest China is crucial. As an important part of minority regions, Ningxia Hui Autonomous Region has insufficient endogenous power for stable economic development and high risk of returning to poverty. On the whole, the Ningxia county network shows a spatial pattern of high in the north and low in the south. However, there are great differences in the centrality of different factor flow networks. The factor connections between most counties are weak, and a close innovation network has not yet been formed. There is an obvious administrative clique structure, showing a certain degree of self-enclosure. The factor flows between counties are relatively uniform and greatly affected by geographic distance. From the perspective of integrated flow, the Ningxia county network presents a distinct core-periphery circle structure. Population size and GDP are the main factors affecting the spatial network. The policy implication of this study is that Ningxia Autonomous Prefecture should coordinate the planning of the region's economy, technology, and transportation, so as to reduce the development gap between counties by enhancing the closeness of the county spatial association network, and ultimately realize the region's high-quality development.

Coping with groundwater pollution in high-nitrate leaching areas: The efficacy of denitrification.

The Ningxia Yellow River irrigation area, characterized by an arid climate and high leaching of NO3--N, exhibits complex and unique groundwater nitrate (NO3--N) pollution, with denitrification serving as the principal mechanism for NO3--N removal. The characteristics of N leaching from paddy fields and NO3--N removal by groundwater denitrification were investigated through a two-year field observation. The leaching losses of total nitrogen (TN) and NO3--N accounted for 10.81-27.34% and 7.59-12.74%, respectively, of the N input. The linear relationship between NO3--N leaching and N input indicated that the fertilizer-induced emission factor (EF) of NO3--N leaching in direct dry seeding and seedling-raising and transplanting paddy fields was 8.2% (2021, R2 = 0.992) and 6.7% (2022, R2 = 0.994), respectively. The study highlighted that the quadratic relationship between the NO3--N leaching loss and N input (R2 = 0.999) significantly outperformed the linear relationship. Groundwater denitrification capacity was characterized by monitoring the concentrations of dinitrogen (N2) and nitrous oxide (N2O). The results revealed substantial seasonal fluctuations in excess N2 and N2O concentrations in groundwater, particularly following fertilization and irrigation events. The removal efficiency of NO3--N via groundwater denitrification ranged from 42.70% to 74.38%, varying with depth. Groundwater denitrification capacity appeared to be linked to dissolved organic carbon (DOC) concentration, redox conditions, fertilization, irrigation, and soil texture. The anthropogenic-alluvial soil with limited water retention accelerated the leaching of NO3--N into groundwater during irrigation. This process enhances the groundwater recharge capacity and alters the redox conditions of groundwater, consequently impacting groundwater denitrification activity. The DOC concentration emerged as the primary constraint on the groundwater denitrification capacity in this region. Hence, increasing carbon source concentration and enhancing soil water retention capacity are vital for improving the groundwater denitrification capacity and NO3--N removal efficiency. This study provides practical insights for managing groundwater NO3--N pollution in agricultural areas, optimizing fertilization strategies and improving groundwater quality.

Establishment of high performance liquid chromatographic fingerprint and determination of 4 kinds of phenolic acid bioactive substances of fruitless Lycium barbarum leaves from Ningxia at different harvesting periods.

"Fruitless Lycium barbarum leaf (FLBL) are the leaves of a new variety of Lycium barbarum in Ningxia, which exhibit higher content of various nutrients, trace elements, and bioactive substances compared to Lycium barbarum fruits and leaves. However, the health and medicinal value as well as the by-products derived from FLBL have not received sufficient attention, and the contents of main components vary at different harvesting periods. Therefore, for the first time this study aimed to establish high-performance liquid chromatography (HPLC) fingerprints and determine the contents of four phenolic acid bioactive substances during different harvesting periods in order to provide an experimental basis for cultivation, collection, and research on FLBL. The results revealed 17 common peaks among 10 batches samples with a similarity ranging from 0.71 to 0.976. The linear relationships R2 for catechin, epicatechin-catechin, chlorogenic acid, and rutin were determined as 0.9999 each; meanwhile, the average recovery rate ranged from 93.92 % to 120.11 %, with an RSD between 0.91 % and 2.82 %. The precision, repeatability stability (24 h), and recovery rate met the requirements outlined in "Chinese Pharmacopoeia". Catechin, epicatechin, and rutin exhibited higher levels from June to August, while chlorogenic acid showed increased levels from July to September. The findings serve as a foundation for quality control measures such as identifying optimal harvest periods or facilitating development and production processes related to Ningxia FLBL."

Spatial-temporal changes of landscape and habitat quality in typical ecologically fragile areas of western China over the past 40 years: A case study of the Ningxia Hui Autonomous Region.

In this paper, we use the InVEST model and five periods of land use data from 1980 to 2020 to assess the habitat quality of the Ningxia Hui Autonomous Region in Western China, which has characteristics of a typical fragile ecosystem. We further analyse the spatial and temporal characteristics of habitat quality evolution and its relationship with land use and landscape pattern indices to explore the close relationship between regional habitat quality changes and human natural resource conservation and utilization. The research results show that the overall habitat quality of Ningxia Hui Autonomous Region was stable and at a moderate level (0.57-0.60) during the 40 years from 1980 to 2020; Habitat patches (2020) with low (24.89%), high (22.45%) and very high (29.81%) quality occupy a larger proportion of the area, followed by very low (13.31%) and moderate levels (9.54%). Over the past 40 years, there have been 275 sample sites in Ningxia where habitat quality has deteriorated, 1593 sample sites where the habitat quality has remained stable, and 184 sample sites where the habitat quality has increased. From 1980 to 2020, the Mean Patch Area of landscape types in Ningxia decreased by 25.9 hm2. The Patch Density increased by 0.06 /hm2. The Largest Patch Index decreased by 15.69%. The Edge Density increased by 2.5 m/hm2. The Contagion Index decreased by 2.99%. The Area-Weighted Mean Patch Fractal Dimension remained basically unchanged (0.01). The Landscape Shape Index showed a trend of first increasing and then decreasing, increasing by 13.94. The Area-Weighted Mean Shape Index has been reduced by 9.45. The Shannon Diversity Index and Shannon Evenness Index both show an increasing trend, but the amplitude is relatively small, with 0.09 and 0.04, respectively. There was a significant spatial aggregation of high and low habitat quality in Ningxia, with high values usually distributed in the northern and southern areas with good natural conditions and low values distributed in areas with frequent human activities and poor natural conditions. The decrease in habitat quality in Ningxia was mainly due to the expansion of cultivated land and construction land, the increase in landscape fragmentation and the resulting decrease in connectivity. On the other hand, due to the implementation of ecological protection measures, such as the project of returning farmland to pasture and grass to forest, the quality of habitats in Ningxia increased. The conclusions of this study support the idea that the conservation of habitat quality in ecologically fragile areas should fully preserve the original natural habitats and reduce the interference of human activities to increase the habitat suitability of the landscape and the habitat connectivity between patches. At the same time, targeted ecological protection policies should be developed to restore the areas where the habitat quality has been damaged and ultimately maintain the stability of biodiversity and ecosystems in ecologically fragile areas. Meanwhile, for ecologically fragile areas with similar ecological characteristics to those of Ningxia, our research supports the idea of increasing the protection of the stability of the original habitats, increasing the proportion of ecological restoration projects, financial investment and seeking cooperation with local community managers and residents will help to improve the quality of the regional habitats and the enrichment of the biodiversity, and ultimately promote the harmonious coexistence of human beings and nature in the modernized sense of the word.

Association between index finger and ring finger length ratios and polymorphism of homeobox A11 gene locus among Ningxia college students / 解剖学报

Objective To investigate the association between the index finger and ring finger length ratio (2D ∶ 4D) and of four loci (rs6461992‚ rs6968828‚ rs7801581‚ rs17427875) polymorphism of homeobox (HOX) A11 gene among Ningxia college students. Methods Digit camera was used to collect frontal hand photos of 667 Han college students (348 males and 319 females) from Ningxia province; Image analysis software was used to mark the anatomical points and measure finger lengths of the index and ring fingers of both hands; multiplex PCR was used to detect each locus polymorphisms of HOXA11 gene; statistical software was used to compare and analyze the differences and associations of 2D ∶4D and gene polymorphisms between different genders. Results Among Ningxia Han college students‚ both left hand and right hand 2D ∶ 4D were significantly higher in females than those of in males (all P< 0. 05)‚ and there were no significant sex differences in right-left hand 2D ∶4D; the genotypes and allele frequencies of rs7801581 locus of HOXA11 gene differed significantly between genders (all P < 0. 05)‚ and none of the other locus polymorphisms showed any significant sex differences; only female left hand 2D ∶4D was significantly associated with rs6461992 locus genotype in the relationship between 2D ∶4D and HOXA11 polymorphisms (P<0. 05). Conclusion There were significant sex differences in 2D ∶ 4D among Han college students in Ningxia‚ and the rs6461992 locus polymorphism of HOXA11 gene may be associated with the formation of 2D ∶4D in females.

Ecological stoichiometry of leaf-litter-fine roots in mixed plantations in mountainous area of Southern Ningxia, China.

The southern mountainous areas in Ningxia are representative regions of the Loess Plateau, with extremely fragile ecological environment. Large area of pure plantations established during the project of Grain for Green has suffered from poor nutrient availability and biodiversity loss, while planting mixed plantations is commonly consi-dered as an effective way to improve the ecological benefits. We selected Robinia pseudoacacia + Picea asperata mixed plantation, R. pseudoacacia + Armeniaca sibirica mixed plantation, A. sibirica pure plantation and R. pseudoa-cacia pure plantation located ina Ningnan mountainous area as test objects. Based on the theory and method of ecological stoichiometry, we measured the C, N and P contents of leaves, litter and fine roots to understand nutrient cycling characteristics of different plantations. The results showed that there was significant difference in foliar stoichiometry of each tree species within the four plantations. P. asperata leaves had the highest C content in the R. pseudoacacia + P. asperata mixed plantation, and R. pseudoacacia leaves had the highest N and P contents in the R. pseudoacacia + A. sibirica mixed plantation. N content of R. pseudoacacia and A. sibirica leaves was significantly higher in mixed plantation compared with that in pure plantation. There was no significant difference in litter biomass, litter C, N, P contents and stoichiometric ratios between the pure and mixed plantations of R. pseudoacacia. Litter biomass in A. sibirica pure plantation was significantly higher than that in R. pseudoacacia + A. sibirica mixed plantation, while litter C content was significantly lower than that in the mixed plantation. Fine root biomass decreased with increasing soil depth in the four plantations, with total fine root biomass being the highest in the R. pseudoacacia + A. sibirica mixed plantation. N content and N:P of fine roots in the R. pseudoacacia + A. sibirica mixed plantation were higher than those in R. pseudoacacia and A. sibirica pure plantations. There was significant negative correlation between N content in leaves and fine roots of R. pseudoacacia + A. sibirica mixed plantation. There were significant negative correlations between the N content of leaves and litter, as well as between the P content of leaves and fine roots in the R. pseudoacacia + P. asperata mixed plantation. P content between litter and fine roots in A. sibirica pure plantation was significantly negatively correlated. Nutrient status of mixed plantations was better than pure plantations in the Ningnan mountainous area, with the mixed plantation of R. pseudoacacia and A. sibirica being the best. Mixed planting reduced nutrient limitation on plant growth to a certain extent.

Hydrochemical analysis and groundwater suitability for drinking and irrigation in an arid agricultural area of the Northwest China.

Groundwater is the foremost water source in the arid and semiarid regions of Northwest China. Assessing groundwater's drinking and irrigation quality is essential for protecting these valuable groundwater resources. In this study, a total of 24 confined groundwater samples and 54 phreatic groundwater samples were collected in the southern and central Ningxia area for hydrochemical analysis and quality assessment. The hydrochemical results revealed that hydrochemical types of phreatic and confined groundwater consistently belonged to Na-SO4-Cl and Na-Mg-SO4-Cl types. The driving forces of groundwater chemistry were determined by gypsum dissolution, silicate dissolution, and positive cation exchange for phreatic and confined aquifers. The entropy-weighted water quality index (EWQI) and irrigation water quality index (IWQI) showed that the drinking water quality and irrigation quality were better in phreatic groundwater than in confined groundwater due to the Neogene-Paleogene groundwater system recharge and strong evaporation. Measures such as controlling groundwater extraction and optimizing well placement need to be implemented. The achievements would be helpful for groundwater management and protection in agricultural areas under semi-arid and arid climates.

Effects of farmland abandonment on anthropogenic-alluvial soil microbiota and contaminant residues in Lycium barbarum fields.

AIMS: There has been an increasing tendency to abandon crop cultivation and farming in old Lycium barbarum (wolfberry) stands to allow for natural restoration. However, little research has been dedicated to deciphering how soil quality changes in L. barbarum fields following abandonment from a physicochemical and microbiological perspective. Here we assessed the effects of farmland abandonment on anthropogenic-alluvial soil microbiota and contaminant residues in L. barbarum fields in Ningxia, China. METHODS AND RESULTS: Soil microbiota, heavy metal, and neonicotinoid pesticide profiles in L. barbarum fields abandoned for one to four years were characterized. Microbial community analysis was performed by high-throughput sequencing of the bacterial 16S ribosomal RNA genes and the fungal nuclear ribosomal internal transcribed spacer region. Soil bacterial diversity increased from before abandonment to year three after abandonment, and fungal diversity peaked in year one after abandonment. Enrichment of potentially beneficial taxa (e.g. Limnobacter, Cavicella) as well as pathogenic taxa (e.g. Ilyonectria) was observed in the abandoned field soils, along with depletion of other taxa (e.g. Planococcus, Bipolaris). Soil copper, zinc, cadmium, imidacloprid, and acetamiprid concentrations all decreased with increasing time since abandonment and had varied correlations with soil quality, microbial diversity, and the relative abundances of major phyla. Soil available phosphorus, nitrate-nitrogen, and pH were the key factors shaping bacterial communities. The structuring of fungal communities was strongly influenced by soil pH, available phosphorus, and available nitrogen contents. CONCLUSIONS: There were positive consequences of farmland abandonment in L. barbarum fields, such as optimized microbial community structure, reduced heavy metal accumulation, and enhanced pesticide degradation.

Spatiotemporal evolution of soil water erosion in Ningxia grassland based on the RUSLE-TLSD model.

Accurate assessment of grassland soil erosion before and after grazing exclusion and revealing its driving mechanism are the basis of grassland risk management. In this study, the long-term soil erosion in Ningxia grassland was simulated by integrating and calibrating the transport limited sediment delivery (TLSD) function with the revised universal soil loss equation (RUSLE) model. The differential mechanisms of soil loss were explored using the GeoDetector method, and the relative effects of precipitation changes (PC) and human activities (HA) on grassland soil erosion were investigated using double mass curves. The measured sediment discharges from six hydrological stations verified that the RUSLE-TLSD model could reliably simulate water erosion in Ningxia. From 1988 to 2018, the water erosion rate of grassland in Ningxia ranged from 74.98 to 14.98 t⋅ha-1⋅a-1, showing an overall downward trend. July to September is the period with the highest of water erosion. The slope is the dominant factor influencing the spatial distribution of water erosion. After grazing exclusion, the net water erosion rate in Ningxia grassland and sub-regions decreased significantly. The double mass curves results show that human activities were the main driver of net erosion reduction. The focus of water erosion control in Ningxia is to control soil erosion in different terrains and protect grassland with slopes greater than 10°.

Metagenomic analysis of the relationship between the microorganisms and the volatiles' development in the wines during spontaneous fermentation from the eastern foothills of the Ningxia Helan mountains in China.

BACKGROUND: The natural fermentation of multispecies microbial communities is responsible for unique flavors of winery regions of the eastern foothills of the Ningxia Helan Mountains in China. However, the participation of different microorganisms in the metabolic network for the development of important flavor substances is not clearly defined. Microbial population and diversity on different fermentation phases of Ningxia wine were analyzed by metagenomic sequencing approach. RESULTS: Gas chromatography-mass spectrometry and ion chromatography were used to identify flavor components, and 13 esters, 13 alcohols, nine aldehydes and seven ketones were detected in volatile substances with odor activity values > 1, and eight organic acids were detected as important flavor components in young wine. Thus, 52 238 predicted protein-coding genes from 24 genera were identified in the Kyoto Encyclopedia of Genes and Genomes level 2 pathways of global and overview maps, and the genes were primarily involved in amino acid metabolism and carbohydrate metabolism. Major microbial genera (Saccharomyces, Tatumella, Hanseniaspora, Lactobacillus, and Lachancea) were closely related to self-characteristic compound metabolism and further contributed to wine flavor. CONCLUSION: This study clarifies the different metabolic roles of microorganisms in flavor formation during Ningxia wine spontaneous fermentation. Saccharomyces, dominant fungi involved in glycolysis and pyruvate metabolism, produces not only ethanol but also two important precursors, pyruvate and acetyl-CoA, which are necessary for the tricarboxylic acid cycle, fatty acid metabolism, amino acid metabolism, and flavor formation. Lactobacillus and Lachancea, dominant bacteria involved in lactic acid metabolism. Tatumella, dominant bacteria involved in amino acid metabolism, fatty acid metabolism, and acetic acid metabolism to produce esters in the Shizuishan City region samples. These findings provide insights into the use of local functional strains to generate unique flavor formation, as well as improved stability and quality, in wine production. © 2023 Society of Chemical Industry.

Detection of the dominant pathogens in diarrheal calves of Ningxia, China in 2021-2022.

Introduction: Calf diarrhea is a complex disease that has long been an unsolved problem in the cattle industry. Ningxia is at the forefront of China in the scale of cattle breeding, and calf diarrhea gravely restricts the development of Ningxia's cattle industry. Methods: From July 2021 to May 2022, we collected diarrhea stool samples from calves aged 1-103 days from 23 farms in five cities in Ningxia, and performed PCR using specific primers for 15 major reported pathogens of calf diarrhea, including bacteria, viruses, and parasites. The effect of different seasons on the occurrence of diarrhea in calves was explored, the respective epidemic pathogens in different seasons were screened, and more detailed epidemiological investigations were carried out in Yinchuan and Wuzhong. In addition, we analyzed the relationship between different ages, river distributions and pathogen prevalence. Results: Eventually, 10 pathogens were detected, of which 9 pathogens were pathogenic and 1 pathogen was non-pathogenic. The pathogens with the highest detection rate were Cryptosporidium (50.46%), Bovine rotavirus (BRV) (23.18%), Escherichia coli (E. coli) K99 (20.00%), and Bovine coronavirus (BCoV) (11.82%). The remaining pathogens such as Coccidia (6.90%), Bovine Astrovirus (BoAstV) (5.46%), Bovine Torovirus (BToV) (4.09%), and Bovine Kobuvirus (BKoV) (3.18%) primarily existed in the form of mixed infection. Discussion: The analysis showed that different cities in Ningxia have different pathogens responsible for diarrhea, with Cryptosporidium and BRV being the most important pathogens responsible for diarrhea in calves in all cities. Control measures against those pathogens should be enforced to effectively prevent diarrhea in calves in China.

Public health implications of Yersinia enterocolitica investigation: an ecological modeling and molecular epidemiology study.

BACKGROUND: Yersinia enterocolitica has been sporadically recovered from animals, foods, and human clinical samples in various regions of Ningxia, China. However, the ecological and molecular characteristics of Y. enterocolitica, as well as public health concerns about infection in the Ningxia Hui Autonomous Region, remain unclear. This study aims to analyze the ecological and molecular epidemiological characteristics of Y. enterocolitis in order to inform the public health intervention strategies for the contains of related diseases. METHODS: A total of 270 samples were collected for isolation [animals (n = 208), food (n = 49), and patients (n = 13)], then suspect colonies were isolated and identified by the API20E biochemical identification system, serological tests, biotyping tests, and 16S rRNA-PCR. Then, we used an ecological epidemiological approach combined with machine learning algorithms (general linear model, random forest model, and eXtreme Gradient Boosting) to explore the associations between ecological factors and the pathogenicity of Y. enterocolitis. Furthermore, average nucleotide identity (ANI) estimation, single nucleotide polymorphism (SNP), and core gene multilocus sequence typing (cgMLST) were applied to characterize the molecular profile of isolates based on whole genome sequencing. The statistical test used single-factor analysis, Chi-square tests, t-tests/ANOVA-tests, Wilcoxon rank-sum tests, and Kruskal-Wallis tests. RESULTS: A total of 270 isolates of Yersinia were identified from poultry and livestock (n = 191), food (n = 49), diarrhoea patients (n = 13), rats (n = 15), and hamsters (n = 2). The detection rates of samples from different hosts were statistically different (χ2 = 22.636, P < 0.001). According to the relatedness clustering results, 270 isolates were divided into 12 species, and Y. enterocolitica (n = 187) is a predominated species. Pathogenic isolates made up 52.4% (98/187), while non-pathogenic isolates made up 47.6% (89/187). Temperature and precipitation were strongly associated with the pathogenicity of the isolates (P < 0.001). The random forest (RF) prediction model showed the best performance. The prediction result shows a high risk of pathogenicity Y. enterocolitica was located in the northern, northwestern, and southern of the Ningxia Hui Autonomous Region. The Y. enterocolitica isolates were classified into 54 sequence types (STs) and 125 cgMLST types (CTs), with 4/O:3 being the dominant bioserotype in Ningxia. The dominant STs and dominant CTs of pathogenic isolates in Ningxia were ST429 and HC100_2571, respectively. CONCLUSIONS: The data indicated geographical variations in the distribution of STs and CTs of Y. enterocolitica isolates in Ningxia. Our work offered the first evidence that the pathogenicity of isolates was directly related to fluctuations in temperature and precipitation of the environment. CgMLST typing strategies showed that the isolates were transmitted to the population via pigs and food. Therefore, strengthening health surveillance on pig farms in high-risk areas and focusing on testing food of pig origin are optional strategies to prevent disease outbreaks.

Interpreting regional ecological security from perspective of ecological networks: a case study in Ningxia Hui Autonomous Region, China.

The rapid economic development and intense human activities have seriously restricted the sustainable development of ecology and the maintenance of ecosystem services. Ecological network can effectively connect fragmented habitats and is an important way to couple landscape structure, ecological process, and function. This study proposes a multimodel coupling framework to explore the ecological security status of Ningxia Hui Autonomous Region (NHAR) under different development scenarios from the perspective of ecological networks. The conclusions are as follows: (1) From 2000 to 2030, grassland and arable land were the main land types of NHAR. Grassland is the main expansion land type under the ecological land protection (ELP) scenario, while construction land is the main expansion land type in two other scenarios. (2) The main gather and change of the ecological sources occurred in the central region, and the ecological expansion should develop from the middle to the south. (3) The average area of ecological sources under BAU and RED scenarios is smaller than that under ELP scenario, and more ecological corridors are needed to connect. (4) The centrality of the ecological sources under the BAU scenario is generally high, but the ecological sources under ELP and RED scenarios have undergone spatial migration. In addition, the urbanization trend of NHAR is different under different scenarios, and more attention should be paid to the maintenance and protection of ecological networks in typical areas. This study can provide important reference for NHAR's ecological space planning and ecological protection policy formulation.

Front-face excitation-emission matrix fluorescence spectroscopy combined with interpretable deep learning for the rapid identification of the storage year of Ningxia wolfberry.

Ningxia wolfberry stored for many years may be disguised as fresh wolfberry by unscrupulous traders and sold for huge profits. In this work, the front-face excitation-emission matrix (FF-EEM) fluorescence spectroscopy coupled with interpretable deep learning was proposed to identify the storage year of Ningxia wolfberry in a lossless, fast and accurate way. Alternating trilinear decomposition (ATLD) algorithm was used to decompose the three-way data array obtained by Ningxia wolfberry samples, extracting the chemically meaningful information. Meanwhile, a convolutional neural network (CNN) model for the identification of the storage year of Ningxia wolfberry, called EEMnet, was proposed. The model successfully classified wolfberry samples from different storage years by extracting the subtle feature differences of the spectra, and the correct classification rate of the training set, test set and prediction set was more than 98%. In addition, a series of interpretability analyses were implemented to break the "black box" of the deep learning model. These results indicated that the method based on FF-EEM fluorescence spectroscopy combined with EEMnet could quickly and accurately identify the year of Ningxia wolfberry in a green way, providing a new idea for the identification of the storage years of Chinese medicinal materials.

Determinants and Assembly Mechanism of Bacterial Community Structure in Ningxia Section of the Yellow River.

The Yellow River is a valuable resource in the Ningxia Hui Autonomous Region and plays a vital role in local human activities and biodiversity. Bacteria are a crucial component of river ecosystems, but the driving factors and assembly mechanisms of bacterial community structure in this region remain unclear. Herein, we documented the bacterial community composition, determinants, co-occurrence pattern, and assembly mechanism for surface water and sediment. In comparison to sediment, the bacterioplankton community showed significant seasonal variation, as well as less diversity and abundance. The network topology parameters indicated that the sediment bacterial network was more stable than water, but the bacterioplankton network had higher connectivity. In this lotic ecosystem, CODMn, Chl a, and pH affected the structure of the bacterioplankton community, while TP was the primary factor influencing the structure of the sediment bacterial community. The combined results of the neutral community model and the phylogenetic null model indicate that Bacterial communities in both habitats were mainly affected by stochastic processes, with ecological processes dominated by ecological drift for bacterioplankton and dispersal limitation for sediment bacteria. These results provide essential insights into future research on microbial ecology, environmental monitoring, and classified management in the Ningxia section of the Yellow River.

[Risk Assessment and Sources of Heavy Metals in Farmland Soils of Yellow River Irrigation Area of Ningxia].

The farmland environment is directly related to the quality and safety of agricultural products. In order to understand the characteristics and main influencing factors of heavy metals in farmland soil in the Yellow River irrigation area of Ningxia, sampling and monitoring were conducted for five consecutive years from 2017 to 2021, and the distribution characteristics and correlation of heavy metals were analyzed. The pollution status and potential ecological risks of heavy metals were evaluated, and the main sources of heavy metals in farmland were analyzed. The results showed that the average values of Pb, As, Zn, Ni, Cu, Hg, Cr, and Cd in the soil of the Ningxia Yellow River irrigation area were 19.74, 11.67, 66.88, 29.09, 22.55, 0.03, 62.27, and 0.19 mg·kg-1, respectively, which were enriched to some extent compared with the background values of the soil environment in Ningxia. Among them, Hg and Cd had middle- and high-grade ecological risk points; however, none of them exceeded the control value of agricultural land soil pollution risk, and all sampling sites had no high-risk or extremely high-risk levels. The results of source analysis based on positive matrix factorization (PMF) and correlation analysis showed that there were five main sources of heavy metals in farmland soil in the study area: natural sources, mixed sources of industrial and mining activities and the production and life of residents, transportation sources, agricultural production activities sources, and industrial sources, with contribution rates of 26.54%, 25.59%, 22.52%, 15.63%, and 9.72%, respectively. On the whole, the heavy metals in farmland soil in the Ningxia Yellow River irrigation area did not exceed the standard, and there was no high-level ecological risk. The production environment of the farmland soil was good, but the contribution rate of human activities to soil heavy metals was large.

Association between hydroxysteroid dehydrogenases gene family single-nucleotide polymorphisms and digit ratio / 解剖学报

Objective To investigate the association between 8 single-nucleotide polymorphisms (SNPs) of hydroxysteroid dehydrogenase (HSD) gene family and human digit ratio (2D ∶ 4D). Methods Randomly selected 808 college students (400 males and 408 females) as subjects, the digit ratio of left and right fingers were measured and calculated using computer image software. Eight SNPs (rs1000283, rs2236903, rs5479, rs56303414, rs676387, rs4445895, rs2066474, rs8190478) in HSD11B and HSD17B gene families were genotyped by multiplex PCR. The association between 2D ∶4D and different genotypes was analyzed by One-Way ANOVA. Results Female left hand(L)2D ∶ 3D, L2D ∶4D, L3D ∶4D, right hand(R)2D ∶4D, R2D ∶5D were significantly higher than male (P0. 05). The genotypes frequency of the 8 SNPs were not significantly associated with digit ratio (2D ∶4D) in both males and females (P>0. 05). Conclusion There are significant gender differences in digit ratio in Ningxia Han college students, but there is no correlation between digit ratio and 8 SNPs in HSD11B and HSD17B gene families, suggesting that HSD11B and HSD17B gene families may have nothing to do with the formation of human digit ratio.

[Temporal and spatial variation of vegetation net primary productivity and its driving factors in Ningxia, China from 2000 to 2019]. / 2000­2019å¹´å®å¤æ¤è¢«å‡€åˆçº§ç”Ÿäº§åŠ›æ—¶ç©ºå˜åŒ–åŠå ¶é©±åŠ¨å› ç´ .

Ningxia is an important agriculture-pastoral area in China. Research on the temporal and spatial variations of net primary productivity (NPP) in this area and its driving factors would help understand the trends and leading factors of NPP variations, and reveal vegetation restoration status and causes. Based on the NPP data of MODIS, we used Theil-Sen Median trend analysis, correlation analysis, overlay analysis and other methods to analyze the spatiotemporal variations and driving factors of NPP in Ningxia. The results showed that NPP of Ningxia vegetation showed a fluctuating upward trend during 2000-2019, with a linear growth rate of 5.46 g C·m-2·a-1. The NPP presented a spatial characteristics of "two high and two low", with the highest in the southern mountain area, followed by the Yellow River irrigation area, and the lowest in the hilly area of the central arid zone and Helan Mountain. 84.2% of the NPP in the study area was under significant restoration, mainly distributed in the central and southern mountainous and hilly areas. The NPP varied significantly with altitude and was significantly affected by the terrain. NPP center of gravity had generally moved to the south, with the increase and growth rate of NPP of vegetation in the south being greater than that in the north. The annual precipitation in Ningxia had shown an increasing trend, while the average annual temperature had slightly decreased. The NPP was significantly affec-ted by precipitation (R2=0.291), whereas the correlation between mean annual temperature and NPP was weak. 96.9% of the study area was at a state of vegetation restoration, which was promoted by both climate change and human activities.