Short-term Association of Meteorological Elements on COVID-19 Pandemic in a Semi-arid City of Northwest China,2021-2022

The coronavirus disease 2019(COVID-19)outbreak in late 2019 significantly impacted global health.The virus’s rapid spread,with its long incubation period and high infection level,caused substantial disruption to regular social frameworks,production,and lifestyles^([1]).COVID-19 is primarily transmitted through close contact,long-range contaminants,and airborne routes.

Climate and topography regulate the spatial pattern of soil salinization and its effects on shrub community structure in Northwest China

Soil salinization may affect biodiversity and species composition,leading to changes in the plant community structure.However,few studies have explored the spatial pattern of soil salinization and its effects on shrub community structure at the ecosystem scale.Therefore,we conducted a transect sampling of desert shrublands in Northwest China during the growing season(June–September)in 2021.Soil salinization(both the degree and type),shrub community structure(e.g.,shrub density and height),and biodiversity parameters(e.g.,Simpson diversity,Margalf abundance,Shannon-Wiener diversity,and Pielou evenness indices)were used to assess the effects of soil salinization on shrub community structure.The results showed that the primary degree of soil salinization in the study area was light salinization,with the area proportion of 69.8%.Whereas the main type of soil salinization was characterized as sulfate saline soil,also accounting for 69.8%of the total area.Notably,there was a significant reduction in the degree of soil salinization and a shift in the type of soil salinization from chloride saline soil to sulfate saline soil,with an increase in longitude.Regional mean annual precipitation(MAP),mean annual evapotranspiration(MAE),elevation,and slope significantly contributed to soil salinization and its geochemical differentiation.As soil salinization intensified,shrub community structure displayed increased diversity and evenness,as indicated by the increases in the Simpson diversity,Shannon-Wiener diversity,and Pielou evenness indices.Moreover,the succulent stems and leaves of Chenopodiaceae and Tamaricaceae exhibited clear advantages under these conditions.Furthermore,regional climate and topography,such as MAP,MAE,and elevation,had greater effects on the distribution of shrub plants than soil salinization.These results provide a reference for the origin and pattern of soil salinization in drylands and their effects on the community structure of halophyte shrub species.

Evaluating the Impact of the Universal Test and Treat Strategy on the Survival of Patients in the Northwest Region of Cameroon

Introduction: The main outcome of efficiently implemented universal test and treat (UTT) program is improved survival. UTT implementation has been ongoing in Cameroon since 2016 but evaluation data are scarce. This study aims to assess the survival of antiretroviral therapy (ART) patients initiated under UTT in Northwest region of Cameroon. Methods: This retrospective cohort study included HIV-positive patients initiated in 2016 at 27 purposefully selected sites and followed until 2021. Data was anonymously abstracted from ART registers and patients’ charts. Kaplan-Meier survival estimates and Cox model were used to compare the survival of patients initiated under UTT with those initiated otherwise, using stata version 14.0. Results: In total, 2490 HIV-positive patients (median age 42.7 years, 94.7% adults, and 69.0% female) participated in the study. Of 1389 patients with viral load (VL) test results, 55% were initiated on ART late. The VL suppression rate of patients initiated late and those initiated early were similar. During follow-up, 1020 (40.9%) participants censored. The survival curves of patients initiated early on ART and those initiated late were similar during the first 2.5 years of follow-up but significantly (p Conclusions: This study confirms the expected impact of UTT. Programs only need to close existing implementation gaps along the critical pathways (diagnosis and treatment) of UTT, focusing more on males.

Spatiotemporal variability of rain-on-snow events in the arid region of Northwest China

Rain-on-snow(ROS)events involve rainfall on snow surfaces,and the occurrence of ROS events can exacerbate water scarcity and ecosystem vulnerability in the arid region of Northwest China(ARNC).In this study,using daily snow depth data and daily meteorological data from 68 meteorological stations provided by the China Meteorological Administration National Meteorological Information Centre,we investigated the spatiotemporal variability of ROS events in the ARNC from 1978 to 2015 and examined the factors affecting these events and possible changes of future ROS events in the ARNC.The results showed that ROS events in the ARNC mainly occurred from October to May of the following year and were largely distributed in the Qilian Mountains,Tianshan Mountains,Ili River Valley,Tacheng Prefecture,and Altay Prefecture,with the Ili River Valley,Tacheng City,and Altay Mountains exhibiting the most occurrences.Based on the intensity of ROS events,the areas with the highest risk of flooding resulting from ROS events in the ARNC were the Tianshan Mountains,Ili River Valley,Tacheng City,and Altay Mountains.The number and intensity of ROS events in the ARNC largely increased from 1978 to 2015,mainly influenced by air temperature and the number of rainfall days.However,due to the snowpack abundance in areas experiencing frequent ROS events in the ARNC,snowpack changes exerted slight impact on ROS events,which is a temporary phenomenon.Furthermore,elevation imposed lesser impact on ROS events in the ARNC than other factors.In the ARNC,the start time of rainfall and the end time of snowpack gradually advanced from the spring of the current year to the winter of the previous year,while the end time of rainfall and the start time of snowpack gradually delayed from autumn to winter.This may lead to more ROS events in winter in the future.These results could provide a sound basis for managing water resources and mitigating related disasters caused by ROS events in the ARNC.

Ecological Network Resilience of Shiyang River Basin: An Arid Inland Watershed of Northwest China

Due to the uncertainties posed by climate change,resilience has become an increasingly important variable for evaluating regional ecosystem stability.The assessment of Ecological Network Resilience(ENR)is crucial for establishing mitigation strategies and sustainable socioeconomic development in arid regions.Shiyang River Basin is an arid watershed in Northwest China with complex characteristics,its ENR and spatial differentiation characteristics in 2020 were investigated in this work based on the Complex Adaptive System(CAS)theory.The results indicated that the mean Ecological Network Resilience Index(ENRI)value for the Shiyang River Basin was 0.390 in 2020,and the mean values in the southern mountainous,middle oasis,and northern desert regions of the basin were 0.598,0.461,and 0.237,respectively,demonstrating evident spatial differences.Additionally,the ENR of the basin exhibited distinct distribution characteristics across different dimension,whereas the trend of the integrated ENR of the basin was consistent with that of elemental,structural,and functional resilience,indicating the constructed three-region ENR model based on the logical relationship of element-structure-function was suitable for evaluation of the ENR in arid inland river watersheds.Furthermore,strategies for enhancing regional ENR were proposed from the perspective of adapting to climate change.

Predicting changes in the suitable habitats of six halophytic plant species in the arid areas of Northwest China

In the context of changes in global climate and land uses,biodiversity patterns and plant species distributions have been significantly affected.Soil salinization is a growing problem,particularly in the arid areas of Northwest China.Halophytes are ideal for restoring soil salinization because of their adaptability to salt stress.In this study,we collected the current and future bioclimatic data released by the WorldClim database,along with soil data from the Harmonized World Soil Database(v1.2)and A Big Earth Data Platform for Three Poles.Using the maximum entropy(MaxEnt)model,the potential suitable habitats of six halophytic plant species(Halostachys caspica(Bieb.)C.A.Mey.,Halogeton glomeratus(Bieb.)C.A.Mey.,Kalidium foliatum(Pall.)Moq.,Halocnemum strobilaceum(Pall.)Bieb.,Salicornia europaea L.,and Suaeda salsa(L.)Pall.)were assessed under the current climate conditions(average for 1970-2000)and future(2050s,2070s,and 2090s)climate scenarios(SSP245 and SSP585,where SSP is the Shared Socio-economic Pathway).The results revealed that all six halophytic plant species exhibited the area under the receiver operating characteristic curve values higher than 0.80 based on the MaxEnt model,indicating the excellent performance of the MaxEnt model.The suitability of the six halophytic plant species significantly varied across regions in the arid areas of Northwest China.Under different future climate change scenarios,the suitable habitat areas for the six halophytic plant species are expected to increase or decrease to varying degrees.As global warming progresses,the suitable habitat areas of K.foliatum,S.salsa,and H.strobilaceum exhibited an increasing trend.In contrast,the suitable habitat areas of H.glomeratus,S.europaea,and H.caspica showed an opposite trend.Furthermore,considering the ongoing global warming trend,the centroids of the suitable habitat areas for various halophytic plant species would migrate to different degrees,and four halophytic plant species,namely,S.salsa,H.strobilaceum,H.glomeratus,and H.capsica,would migrate to higher latitudes.Temperature,precipitation,and soil factors affected the possible distribution ranges of these six halophytic plant species.Among them,precipitation seasonality(coefficient of variation),precipitation of the warmest quarter,mean temperature of the warmest quarter,and exchangeable Na+significantly affected the distribution of halophytic plant species.Our findings are critical to comprehending and predicting the impact of climate change on ecosystems.The findings of this study hold significant theoretical and practical implications for the management of soil salinization and for the utilization,protection,and management of halophytes in the arid areas of Northwest China.

Effect of CO_(2)flooding in an oil reservoir with strong bottom-water drive in the Tahe Oilfield,Tarim Basin,Northwest China

The dissolution and diffusion of CO_(2)in oil and water and its displacement mechanism were investigated by laboratory experiment and numerical simulation for Block 9 in the Tahe oilfield,a sandstone oil reservoir with strong bottom-water drive in Tarim Basin,Northwest China.Such parameters were analyzed as solubility ratio of CO_(2)in oil,gas and water,interfacial tension,in-situ oil viscosity distribution,remaining oil saturation distribution,and oil compositions.The results show that CO_(2)flooding could control water coning and increase oil production.In the early stage of the injection process,CO_(2)expanded vertically due to gravity differentiation,and extended laterally under the action of strong bottom water in the intermediate and late stages.The CO_(2)got enriched and extended at the oil-water interface,forming a high interfacial tension zone,which inhibited the coning of bottom water to some extent.A miscible region with low interfacial tension formed at the gas injection front,which reduced the in-situ oil viscosity by about 50%.The numerical simulation results show that enhanced oil recovery(EOR)is estimated at 5.72%and the oil exchange ratio of CO_(2)is 0.17 t/t.

Comprehensive applicability evaluation of four precipitation products at multiple spatiotemporal scales in Northwest China

Precipitation plays a crucial role in the water cycle of Northwest China.Obtaining accurate precipitation data is crucial for regional water resource management,hydrological forecasting,flood control and drought relief.Currently,the applicability of multi-source precipitation products for long time series in Northwest China has not been thoroughly evaluated.In this study,precipitation data from 183 meteorological stations in Northwest China from 1979 to 2020 were selected to assess the regional applicability of four precipitation products(the fifth generation of European Centre for Medium-Range Weather Forecasts(ECMWF)atmospheric reanalysis of the global climate(ERA5),Global Precipitation Climatology Centre(GPCC),Climatic Research Unit gridded Time Series Version 4.07(CRU TS v4.07,hereafter CRU),and Tropical Rainfall Measuring Mission(TRMM))based on the following statistical indicators:correlation coefficient,root mean square error(RMSE),relative bias(RB),mean absolute error(MAE),probability of detection(POD),false alarm ratio(FAR),and equitable threat score(ETS).The results showed that precipitation in Northwest China was generally high in the east and low in the west,and exhibited an increasing trend from 1979 to 2020.Compared with the station observations,ERA5 showed a larger spatial distribution difference than the other products.The overall overestimation of multi-year average precipitation was approximately 200.00 mm and the degree of overestimation increased with increasing precipitation intensity.The multi-year average precipitation of GPCC and CRU was relatively close to that of station observations.The trend of annual precipitation of TRMM was overestimated in high-altitude regions and the eastern part of Lanzhou with more precipitation.At the monthly scale,GPCC performed well but underestimated precipitation in the Tarim Basin(RB=-4.11%),while ERA5 and TRMM exhibited poor accuracy in high-altitude regions.ERA5 had a large bias(RB≥120.00%)in winter months and a strong dispersion(RMSE≥35.00 mm)in summer months.TRMM showed a relatively low correlation with station observations in winter months(correlation coefficients≤0.70).The capture performance analysis showed that ERA5,GPCC,and TRMM had lower POD and ETS values and higher FAR values in Northwest China as the precipitation intensity increased.ERA5 showed a high capture performance for small precipitation events and a slower decreasing trend of POD as the precipitation intensity increased.GPCC had the lowest FAR values.TRMM was statistically ineffective for predicting the occurrence of daily precipitation events.The findings provide a reference for data users to select appropriate datasets in Northwest China and for data developers to develop new precipitation products in the future.

The Concurrent Record-breaking Rainfall over Northwest India and North China in September 2021

Extremely heavy rainfall occurred over both Northwest India and North China in September 2021.The precipitation anomalies were 4.1 and 6.2 times interannual standard deviation over the two regions,respectively,and broke the record since the observational data were available,i.e.,1901 for India and 1951 for China.In this month,the Asian uppertropospheric westerly jet was greatly displaced poleward over West Asia,and correspondingly,an anomalous cyclone appeared over India.The anomalous cyclone transported abundant water vapor into Northwest India,leading to the heavy rainfall there.In addition,the Silk Road pattern,a teleconnection pattern of upper-level meridional wind over the Eurasian continent and fueled by the heavy rainfall in Northwest India,contributed to the heavy rainfall in North China.Our study emphasizes the roles of atmospheric teleconnection patterns in concurrent rainfall extremes in the two regions far away from each other,and the occurrence of rainfall extremes during the post-or pre-monsoon period in the northern margins of monsoon regions.

Correction to:Modelling the response of larch growth to age,density,and elevation and the implications for multifunctional management in northwest China

In Table 3 of the published version,“Parameters fi tted for tree height and DBH growth models of Eq.(6)”,the parameters letter mismatched the corresponding values.Hence,the authors regret that this may lead to mistakes in the tree height and DBH simulation based on the model Eq.(6).The correct Table 3 with exact parameter values is listed as follow.

Determinants of Smallholder Farmers Adoption of Acacia decurrens in Northwest Ethiopia

Planting a fast-growing multipurpose Acacia decurrens (AD) tree is one of the climate-smart agricultural practices that have been promoted in Ethiopia, which is widely practiced and an important livelihood strategy in Awi zone. However, the extent of its adoption varies considerably among households in the study area. This study investigated the determinants of intensity of adoption of AD among 385 randomly selected rural households in Awi Zone. Data were gathered using a cross-sectional household survey. Descriptive statistics and Two-limit Tobit model were employed for data analysis. The result of the study shows that on average the intensity of adoption of AD was 0.43 (43% of the total cropland area), though majority of the farmers (48.8%) belong to low level of adoption. The result of the analysis shows that being male, educational level, access to seedling, experience in growing the tree, extension contact has positive and significant relationship with the intensity of adoption. Age of head of household, land holding size, livestock holding size, soil fertility status, disease emergence and road distance have negative and significant influence on intensity of adoption. These suggest that expanding road infrastructure, education, access to seedling, secure land property right, disease management, and provision of extension services related to the AD can also improve smallholder farmers’ intensity of AD adoption. The generated information provides a picture of the study area’s situation to the attention of policy makers, development practitioners and institutional service providers to formulate a better policy intervention to sustain smallholder farmers’ AD plantation.

Long-term improvements in water conservation functions at Qilian Mountain National Park, northwest China

Water conservation is one of the most important ecosystem functions.This study uses the InVEST model to examine the water conservation function of the Qilian Mountain National Park(QMNP),an important water supply area in northwest China.We analyzed the spatiotemporal water conservation patterns of QMNP from 1988 to 2019.It showed that the water conservation capacity in QMNP has increased over the past 32 years,reaching a peak of 6.495×108 m3 in 2019.The area with an increased water conservation capacity is 12 times larger than the area with a reduced capacity.We also examined how climatic,land-use,vegetation coverage,and topographical factors influence water conservation functions.We found that precipitation is the main climatic factor in water conservation.The water conservation function also varies with land-cover type,with forests having the highest capacity,followed by grasslands.Lastly,topographical factors,including altitude and slope,also shape the spatial patterns of water conservation functions in QMNP.

西北地区冠心病患者ApoE基因多态性分布研究以及对他汀类药物使用的指导意义

目的探讨我国西北地区冠心病患者ApoE基因多态性分布情况。方法选取西安交通大学第一附属医院冠心病治疗患者2388例,检测ApoE的基因型,统计基因型及等位基因分布特征,并对比国内外其他地区基因型及等位基因分布差异。结果E3E3、E3E4、E2E3、E2E4、E4E4、E2E2,分别占患者总数的70.31%、15.20%、11.93%、1.30%、0.75%、0.50%。检测出ApoE E2、E3及E4等位基因频率分别为7.12%、83.88%、9.00%。不同性别、年龄冠心病患者之间ApoE基因型及等位基因分布差异均无统计学意义;不同国家和地区ApoE基因型及等位基因分布差异均具有统计学意义。结论西北地区冠心病患者ApoE基因型主要以E3E3、E3E4为主,等位基因以E3为主,有助于目前血脂正常的人群预测血脂异常风险,从而早期通过调节饮食和生活方式来控制血脂,预防或延缓心脑血管疾病的发生。同时也可为患者合理使用他汀类药物提供一定的参考依据。

塔里木盆地西北缘沙井子断裂带的构造特征与形成演化

塔里木盆地西北缘的沙井子断裂带,位于塔北隆起的温宿凸起和北部坳陷的阿瓦提凹陷之间。它是塔里木盆地的一条一级断裂带,由沙井子断裂、英雄断裂、温宿断裂和沙南断裂组成。其中沙井子断裂是主干断裂,其它3条是其分支断裂。本轮研究新发现温宿分支断裂,并将沙南断裂解释为英雄断裂前缘的反冲断层,归属沙井子断裂带。沙井子断裂带的雏形形成于奥陶纪末—志留纪初,在泥盆纪末—石炭纪、二叠纪末—三叠纪初、侏罗纪末—白垩纪初、白垩纪末—古近纪初和新近纪—第四纪发生过多期冲断作用和新近纪末—第四纪初的张扭性构造变形后,才最终定型。沙井子断裂带是一条断控油气富集区带,温宿油田、托探1油藏、沙南1油藏、新苏地1油气藏等都受其控制。

基于多变量灰色模型的台风强度模拟方法

随着台风全路径模拟技术的不断完善,全海域、大范围的台风危险性分析方法得到发展,然而强度模型的模拟精度不能满足需求。针对台风强度演变受多因素影响、动力关系复杂及强度变化随机性强的特点,基于多变量灰色模型对台风强度模拟方法进行研究,并建立起台风多变量灰色强度模型。利用该模型还原了台风“山竹”的强度演变过程,同时对西北太平洋地区整体台风强度进行模拟及检验分析。结果表明:垂直风切变及垂直速度与台风强度的灰色关联度分别为0.771 8、0.745 1,显著高于其他3个环境因素;台风“山竹”强度模拟的后验差比值及小概率误差分别为0.349 1、0.960 8,达到了最高模拟精度;模型模拟所得西北太平洋地区整体的强度变化趋势及分布特征均与地区实际情况保持一致。

基于西北地域特色的《水域生态学》实践课程改革探索

《水域生态学》是水产养殖本科专业的核心基础课,具有很强的实践性和应用性。针对当前《水域生态学》实践课程内容设置及现状,提出一系列教学改革策略,重点关注课程学时与内容、师资力量与资源配置以及考核机制等方面的优化,旨在提升实践教学质量,实现更高效、全面、系统化的育人效果。

西北地区主要锂矿资源分布特征及地球化学找矿远景预测

为圈定锂成矿远景区,采用已有1∶20万地球化学数据,选取西昆仑-阿尔金和阿尔泰两个主要锂矿带,基于锂元素地球化学空间分布及异常特征圈定锂矿远景区,为找矿突破战略行动选区服务。基于重点锂矿带以往1∶20万地球化学数据库,对元素相关性、背景及异常特征等参数进行再分析,结合已有锂矿床或锂矿(化)点,圈定找矿远景区。在昆仑-阿尔金地区圈定锂地球化学异常区15处,在阿尔泰圈定锂地球化学异常区12处。研究圈定27处异常区可为下一步锂矿找矿工作部署提供参考依据。

2005-2020年亚洲中部干旱区生态站月潜在蒸散量数据集

潜在蒸散表征大气蒸发能力,是衡量区域蒸发能力的重要指标,也是评价气候干旱程度变化、水资源供需平衡、植被耗水量等的关键参数。在收集中亚生态系统监测网络12个生态站和中国生态系统研究网络(CERN)11个位于西北干旱区生态站的气象观测数据基础上,经过数据质量控制与插补,采用Penman-Monteith模型计算潜在蒸散量,生成了2005-2020年亚洲中部干旱区生态站月潜在蒸散量数据集。本数据集时间序列较长、覆盖多种生态系统类型,可作为亚洲中部干旱问题研究的基础数据、模型输入数据、模拟结果验证数据等,也可为该区域水资源的合理开发与利用、生态环境保护等方面研究提供数据支撑。

西北高等教育全面振兴的“特区模式”研究

振兴西北高等教育是贯彻落实党的二十大报告关于教育、科技、人才三位一体建设的重要内容。文章以“粤港澳大湾区”高等教育集群式发展为借鉴,提出建立西北高等教育“特区模式”的必要性和可行性,对其面临的区域性国家政策支持和地方政府投入有限、区域内学科建设与产业发展耦合度不高、外部环境对西部高校人才建设的冲击等不利因素进行了回应与分析,提出优化顶层政策设计和加大高等教育投入,增强产业升级贡献度和构建人才共享机制等对策,以期为振兴西北高等教育,促进区域经济社会高质量发展,推动西北地区共同富裕提供“靶向治疗”的重要依据。

三维激电法在黔西北某铅锌矿勘查中的应用

黔西北铅锌成矿区是贵州省重要的铅锌产地之一,区内发现的某超大型铅锌矿深部及外围被认为仍具较大找矿潜力。随着埋深加大,地质条件更复杂,通过地球物理方法探查直接或间接的矿致异常愈加被认可。为研究三维激电方法在黔西北铅锌成矿区的勘查效果,首先在典型矿床开展了方法有效性及装置参数试验,结果显示梯度四极加三极装置联合反演显示的高极化率(17~20 mV/V)、低电阻率(158~251Ω·m)与已知铅锌矿体空间位置对应较好,然后应用到外围空白区,圈定了高极化、低电阻激电异常,经钻孔验证为含黄铁矿及铅锌矿(化)地质体。表明通过低电阻率高极化率圈定含黄铁矿物地质体异常,结合地质分析,间接指示铅锌矿体空间位置是本区三维激电方法应用的思路,对地区同类型铅锌矿地球物理勘探具有参考意义。