To understand the current situation of institutional registration in Shaanxi Province after the implementation ofregistration system management in drug clinical trial institutions.Relevant information was collected on...To understand the current situation of institutional registration in Shaanxi Province after the implementation ofregistration system management in drug clinical trial institutions.Relevant information was collected on the“Announcement on the Accreditation of Drug Clinical Trial Institutions”issued by the National Medical Products Administration from 2005 to August 2022,the record management information system of drug and medical device clinical trial institutions,and the drug clinical trial registration and information publicity platform.A retrospective analysis was carried out in terms of institutional development,regional distribution,registered majors,principal investigators,and the number of drug clinical trials.After the implementation of institution registration,the number of drug clinical trial institutions in Shaanxi Province increased by 47.4%,884 principal investigators were registered,the number of registered majors expanded from 58 qualified to 117,and the professional scope increased by 50.4%.The policy of institution registration is conducive to promoting the rational use of medical resources and the development of drug clinical trial institutions and improving the healthy development of the pharmaceutical industry in Shaanxi Province.展开更多
[Objective] The aim was to explore eco-economy in ecological fragile region with Wuqi County in Shaanxi Province as an example. [Method] Eco-economy development and major environmental problems in Wuqi County in Shaan...[Objective] The aim was to explore eco-economy in ecological fragile region with Wuqi County in Shaanxi Province as an example. [Method] Eco-economy development and major environmental problems in Wuqi County in Shaanxi Province were researched based on local social and economic conditions, population of impoverished people and environment vulnerability. [Result] The areas with vulnerable environment and backward economy should establish a virtuous circle between economy and environment and a sustainable model of economic development. [Conclusion] It is significant to change the severe situation of environment deterioration and to promote ecological civilization.展开更多
The Loess Plateau in northern Shaanxi Province of China covers Yulin, Yan'an, and Tongchuan cities mainly. The kind of physiognomy is complicated and various, including the transitional region of the sand and wind, t...The Loess Plateau in northern Shaanxi Province of China covers Yulin, Yan'an, and Tongchuan cities mainly. The kind of physiognomy is complicated and various, including the transitional region of the sand and wind, the hilly-gully fragile region, the pimple mound region from North to South. Large-scale land reclamation projects that are severely affecting these ecosystems have been implemented. In this paper, we reported an investigation to the changes in land use and ecosystem services on the Loess Plateau in northern Shaanxi Province from 1978 to 2000. We used three LANDSAT TM and/or ETM data sets to estimate the changes in the size of five land-cover/land-use categories, and we also used previously published value coefficients to estimate the changes in the value of ecosystem services delivered by each land category. Finally, we ranked the contribution of various ecosystem functions to the overall value of the ecosystem services, we have estimated that the annual value of the ecosystem services is 56.95 billon RMB yuan in the Loess Plateau in northern Shaanxi Province in 2000. In the region, from 1978 to 2000, the economic value of the fixing carbon was higher, the economic value of water conservation was the lowest, but the economic value of the NPP, fixing carbon, and supplying oxygen accounted for above ninety percent of the total value, obviously the vegetation created the biggest ecosystem service value. We can conclude that future land-use policy formulation should give precedence to the conservation of these ecosystems over uncontrolled reclamation, and that further land reclamation should be based on rigorous environmental impact analyses.展开更多
Using the theory and method of the ecological footprint, and combining the changes of regional land use, resource environment, population, society and economy, this paper calculated the ecological footprint, ecologica...Using the theory and method of the ecological footprint, and combining the changes of regional land use, resource environment, population, society and economy, this paper calculated the ecological footprint, ecological carrying capacity and ecological surplus/loss in 1986-2002 on the Loess Plateau in northern Shaanxi Province. What is more, this paper has put forward the concept of ecological pressure index, set up ecological pressure index models, and ecological security grading systems, and the prediction models of different ecological footprints, ecological carrying capacity, ecological surplus and ecological safety change, and also has assessed the ecological footprint demands of 10,000 yuan GDE The results of this study are as follows: (1) the ecological carrying capacity in northern Shaanxi shows a decreasing trend, the difference of reducing range is the fastest; (2) the ecological footprint appears an increasing trend; (3) ecological pressure index rose to 0.91 from 0.44 during 1986-2002 on the Loess Plateau of northern Shaanxi with an increase of 47%; and (4) the ecological security in the study area is in a critical state, and the ecological oressure index has been increasing rapidlv.展开更多
A new ootype collected from the Upper Cretaceous Lijiacun Formation in the Shangdan Basin,Shaanxi Province is described in this paper. Based on general external shape, size, eggshell thickness and honeycomb-like eggsh...A new ootype collected from the Upper Cretaceous Lijiacun Formation in the Shangdan Basin,Shaanxi Province is described in this paper. Based on general external shape, size, eggshell thickness and honeycomb-like eggshell microstructure, eggs are referable to the oofamily Faveoloolithidae. Compared with other members of Faveoloolithidae, specimens described in this paper show special characteristics:adjacent pores are usually separated by two eggshell units between which often develop interspaces;columnar eggshell units are relatively closely arranged in radial view. According to these characteristics,we erect a new oogenus and a new oospecies: Duovallumoolithus shangdanensis oogen. et oosp. nov. The new discovery expands the diversity of Faveoloolithidae.展开更多
Efficiency and sustainability of grain production are now important in China. In this study, the grain production systems of Jiangsu and Shaanxi Provinces were compared, to analyze their efficiency and sustainability ...Efficiency and sustainability of grain production are now important in China. In this study, the grain production systems of Jiangsu and Shaanxi Provinces were compared, to analyze their efficiency and sustainability in terms of utilization of natural resources, inputs of purchased energy and materials, and outputs. Flows of energy and materials between environment and human society were identified, and the natural and human work involved in generating inputs as materials or energy were valued in terms of equivalent amount of solar energy required for their production using emergy method. The results showed environmental resources were continually playing a less important role in the systems, when inorganic subsidiary emergy inputs increased drastically while organic ones decreased or increased little. Deterioration of input emergy structure affected the systems′ efficiency and sustainability,resulting in emergy investment ratios and environmental loading ratios increasing while yield ratios and sustainability indices decreasing. In general, efficiency and sustainability of grain production in Jiangsu are worse than those in Shaanxi. This analysis also suggested that inorganic subsidiary emergy should be introduced properly, and peasants in Jiangsu should utilize natural conditions wisely while those in Shaanxi pay enough attention to soil and surface water conservation.展开更多
This study aims to investigate the mechanisms and health risks of fluoride enrichment in groundwater in the Loess Plateau,China.By taking Dali County,Shaanxi Province,China as an example,this study obtains the followi...This study aims to investigate the mechanisms and health risks of fluoride enrichment in groundwater in the Loess Plateau,China.By taking Dali County,Shaanxi Province,China as an example,this study obtains the following results through field investigation and the analyses of water,soil,and crop samples.(1)The groundwater can be divided into two major types,namely the Quaternary pore-fissure water and Karst water.The Karst area and sandy area have high-quality groundwater and serve as the target areas for optional water supply.The groundwater in the study area is slightly alkaline and highly saline.Meanwhile,high-fluoride groundwater is mainly distributed in the loess and river alluvial plains in the depression area of the Guanzhong Basin and the discharge areas of the groundwater,with the highest fluoride concentration exceeding seven times the national standard.(2)Fluoride in groundwater mainly originates from a natural source and human activities.The natural source refers to the fluoride-bearing minerals in rocks and soil,and the fluoride from this source is mainly controlled by natural factors such as climate,geologic setting,pH,specific hydrochemical environment,ion exchange,and mineral saturation.Human activities in modern life can be further divided into industrial and agricultural sources primarily.(3)The health risks of fluoride contamination are very high in the Loess Plateau,especially for children compared to adults.Meanwhile,the risks of fluoride exposure through food intake are higher than those through drinking water intake.The authors suggest selecting target areas to improve water supply and ensure the safety of drinking water in the study area.Besides,it is necessary to plant crops with low fluoride content or cash crops and to conduct groundwater treatment to reduce the fluoride concentration in drinking water.These results will provide a theoretical basis for safe water supply in the faulted basin areas in the Loess Plateau.展开更多
This study was conducted to define the taxonomic status of Spermophilus in the plague area of Dingbian County in Shaanxi Province,China,through the two-factor variance analysis of morphological characteristics,DNA bar...This study was conducted to define the taxonomic status of Spermophilus in the plague area of Dingbian County in Shaanxi Province,China,through the two-factor variance analysis of morphological characteristics,DNA barcoding,and chromosome karyotype analysis.展开更多
The Baguamiao gold deposit in Fengxian County, Shaanxi Province, is a recentlyexplored super-large gold ore deposit. A comprehensive and deep-going study has revealedthat it is a polygenetic deposit: early-stage miner...The Baguamiao gold deposit in Fengxian County, Shaanxi Province, is a recentlyexplored super-large gold ore deposit. A comprehensive and deep-going study has revealedthat it is a polygenetic deposit: early-stage mineralization due to shearing, middle-stagemineralization due to hydrothermal alteration, and late-stage mineralization due toweathering, leaching and concentration at shallow depths. Shearing played a dominant role inthe formation of gold orebodies.展开更多
[ Objective] The research aimed to study change characteristics and formation cause of summer precipitation abnormality in Loess Plateau of northern Shaanxi Province. [ Method] Based on summer precipitation data at 15...[ Objective] The research aimed to study change characteristics and formation cause of summer precipitation abnormality in Loess Plateau of northern Shaanxi Province. [ Method] Based on summer precipitation data at 15 observation stations in Loess Plateau of northern Shaanxi Province and NCEP/NCAR dataset from 1961 to 2008, change characteristics of summer precipitation in the region were investigated by using linear trend estimation and composite analysis. [Result] Summer rainfall had decrease trend in most parts of northem Shaanxi Province, but had increase trend in western and southern regions. The interannual and interdecadal variations were obvious. It had a large amount of precipitation from the mid- 1970s to the mid-1990s, while summer rainfall had decrease trend after the mid-1990s and increase trend in recent years. In wet years, it was a large positive anomaly zone from western Ural Mountains to northem Lake Baikal at middle and high latitudes, indicating that there was a blocking high over the Ural Mountains, while it was negative anomaly zone from northern Okhotsk Sea to Lake Baikal. From Northwest Pacific Ocean to Bo- hal Sea Bay and North China, it was a wide range of significant positive anomaly zone, which was favorable for Westem Pacific subtropical high ex- tending westward and northward. The analysis in dry years showed opposite circulation configuration. It was " -, +, -" wave train distribution in middle and high latitudes and positive anomaly zone along the Sea of Okhotsk. Western Pacific subtropical high was also by south and east. Major water vapor was from southeast direction in wet years, and abundant water vapor caused more summer rainfall in northern Shaanxi. In dry years, water vapor was from westerly tuming southerly flow. It was weaker and by east. [ Conclusion] The research provided reference for reasonable utilization of summer precipitation in the zone.展开更多
Objectives Firstly,according to the characteristics of COVID-19 epidemic and the control measures of the government of Shaanxi Province,a general population epidemic model is es-tablished.Then,the control reproduction...Objectives Firstly,according to the characteristics of COVID-19 epidemic and the control measures of the government of Shaanxi Province,a general population epidemic model is es-tablished.Then,the control reproduction number of general population epidemic model is obtained.Based on the epidemic model of general population,the epidemic model of general population and college population is further established,and the control reproduction number is also obtained.Methods For the established epidemic model,firstly,the expression of the control reproduc-tion number is obtained by using the next generation matrix.Secondly,the real-time reported data of COVID-19 in Shaanxi Province is used to fit the epidemic model,and the parameters in the model are estimated by least square method and MCMC.Thirdly,the Latin hypercube sampling method and partial rank correlation coefficient(PRCC)are adopted to analyze the sensitivity of the model.Conclusions The control reproduction number remained at 3 from January 23 to January 31,then gradually decreased from 3 to slightly greater than 0.2 by using the real-time reports on the number of COVID-19 infected cases from Health Committee of Shaanxi Province in China.In order to further control the spread of the epidemic,the following measures can be taken:(i)reducing infection by wearing masks,paying attention to personal hygiene and limiting travel;(i)improving isolation of suspected patients and treatment of symptomatic individuals.In particular,the epidemic model of the collge population and the general population is estab-lished,and the control reproduction number is given,which will provide theoretical basis for the prevention and control of the epidemic in the colleges.展开更多
Studies on rocks and ores of Jianchaling ore deposit, southern Shaanxi, show that REE patterns in the ores clearly differ from that in ultrabasic and acidic rocks. The REE pattern in Ni ore is similar to that in Au ...Studies on rocks and ores of Jianchaling ore deposit, southern Shaanxi, show that REE patterns in the ores clearly differ from that in ultrabasic and acidic rocks. The REE pattern in Ni ore is similar to that in Au ore and is characterized by typical enrichment in LREE and sharp negative Eu and Ce anomalies, indicating that Ni ore and Au ore were formed from the same hydrothermal solution. δ Eu and δ Ce variations reflect that Ni ore is formed at higher temperature and relative reduction environment, and Au ore at lower temperature and relative oxidation environment. The characteristics imply that the ore forming materials were derived from the ultrabasic rock and the hydrothermal solution is a post magmatic acidic solution.展开更多
Triplet surveys were conducted in the city of Xi'an and two villages (one in the vicinity and the other at a distance) in Shaanxi fuvince in China in October-November (when agricultural activitis were low), 1997, ...Triplet surveys were conducted in the city of Xi'an and two villages (one in the vicinity and the other at a distance) in Shaanxi fuvince in China in October-November (when agricultural activitis were low), 1997, to elucidate nutrient intakes with a focus on possible urban-rural differences. Total food duplicate samples were collected from non-smoking and non-habitually dhnking adult healthy women (ahout 50 subjects per site and 149 in total). The nutrient intakes were estimated from the weight of food items in reference to national food composition tables. On average, the women took 1873 kcal energy, 54 g protein and 37 g lipid per day, with a lipid eneny ratio of 18.4%. Both excess and insufficient energy intake was observed as a result of food intake analysis and body mass index determination. With regard to minor nutrient intakes, insufficiency was serious in the case of calcium, vitamin A and vitamin B2, but not with iron. Whereas dependency on plant foods for sources of energy and protein was common to the three regions, Xi' an people consumed more animal foods than those in the villages. Intake of fish and shellfish was quite low throughout the three regions. Among the four types of cereals, wheat was consumed most substantially in the three regions and in three meals (except for the village where people essentially did not take lunch in reflection of low agricultural activities), whereas rice was consumed more in Xi'an than in the two villages. Maize consumption was higher in the two villages (especially for breakfast) than in the city.In contrast, foxtail millet (although in small amounts) was taken primarily in Xi'an and ouly at the time of breakfast.展开更多
Situated in the Henan-Shaanxi fault-uplift area on the southern margin of the Sino-Korean Paraplatform,the jinduicheng porphyry molybdenum deposit is the most important molybdenum producer in China.During Yenshanian t...Situated in the Henan-Shaanxi fault-uplift area on the southern margin of the Sino-Korean Paraplatform,the jinduicheng porphyry molybdenum deposit is the most important molybdenum producer in China.During Yenshanian the Jinduicheng granite porphyry was emplaced in metaspilite of the Proterozoic XiongerGroup,controlled by a NW trending fault Mineral compositions are mainly quartz (25-40%),microclineand microcline perthite(27-40%)and plagioclase(An8-14-,14-32%),associated with minor biotite andmuscovite,and phenocrysts are made up of K-feldspar,quartz and phagioclase.Accessory minerals includemagmatite,apatite and zircon,The porphyry contains SiO2 73.83% and K2O+Na2O 8.06%(withK2O/Na2O ratio being 1.82),beloning to the calc-alkaline series Mineralization occurs in the porphyry body and biotitized and hornfelsized spilite Within the exocontactzone.The maximum depth of mineralization reaches 1000 meters below the surface.According to mineralassemblage,ore veins are classified into five types:(l) Pyrite-quartz;(2) Pyrite-K-feldspar-quartz; (3)pyrite-molybdenite-quartz:(4) pyrite-molybdenite-K-feldspar-quartz;and(5) Muscovitefluorite-pyrite-molybdenite-quartz. As the most important economic molybdenum mineral,molybdenite occurs in various forms.Wall-rockalterations show a gross zonation of K-feldspathization-greisenization→silicification→propylitization fromthe porphyry outwards,of which silicification is most intense and has close genetic relationship with Momineralization. Fluid inclusion studies yield homogeneous temperatures ranging from 240to240℃,with the main stagebetween 400 and 300℃.Gas inclusions frequently coexist with multiphase inclusions containing suchdaughter minerals as halite,sylvite,molybdenite and K-feldspar.Under moderate-high temperatures,lowerfo2,high fs2 and weak。acidity conditions,boiling of ore-forming fluids is prerequisite for the Precipitation ofmolybdenite. Sulfur,oxygen and carbon isotopic compositions suggest that at the high temperature stage(450℃)magmatic water is dominant and at the main ore-forming stage a mixture of mixture of magmatic water and meteoricwater is expected.At the late stage,the mixture is predominated by meteoric water.Sulfur and molybdenumare mostly of magmatic origin.展开更多
Shaanxi is situated in China’s hinterland,with a total area of 205,600 squarekilometers and a population of 34.8million. The province is composed of 10cities and prefectures (including the sixprovincial cities of Xi...Shaanxi is situated in China’s hinterland,with a total area of 205,600 squarekilometers and a population of 34.8million. The province is composed of 10cities and prefectures (including the sixprovincial cities of Xi’an, Baoji, Xianyang,Tongchuan, Weinan and Jiangzhong, andfour prefectures of Ankang, Shanluo, Yan’anand Yulin), 107 county-level cities, countiesand districts, with Xi’an as the provincialcapital. The average temperature of theprovince is 8 - 16 ℃, average rainfall 674mm, and frost-free period 150 - 270 days. Inthe north lies the Huangtu Plateau, in thesouth is Mount Qingba, and in the centre isthe Guanzhong Plain. Shaanxi is abundant with展开更多
[ Objective] The study aimed to analyze the changing trends of surface water quality and their causes of Weihe River in Shaanxi Province over past ten years. [ Method] Based on the available monitoring data of water q...[ Objective] The study aimed to analyze the changing trends of surface water quality and their causes of Weihe River in Shaanxi Province over past ten years. [ Method] Based on the available monitoring data of water quality of Weihe River in Shaanxi Province from 2001 to 2010, the changing trends of surface water quality of Weihe River in Shaanxi Province during recent ten years were assessed by using the assessment method of surface water quality according to the Assessment Method of Surface Water Quality and Environmental Quality Standards for Surface Water (GB 3838-2002). Moreover, the possible reasons for the trends were also proposed. [ Result] From 2001 to 2010, there was a relatively decrea- sing trend of water pollution in Weihe River due to the considerable decline in the content of the main environmental pollutants like permanganate in- dex, 5-day biochemical oxygen demand ( BOD5 ), ammonia nitrogen, oil and volatile phenol. Meanwhile, the comprehensive pollution index fell by 62.7%, eliminating Weihe River's black and stink on schedule. However, the overall surface water quality of Weihe River was still polluted heavily in each year, and the pollution control of Xi'an section should be paid more attention to. [ Conclusion] The research could provide scientific refer- ences for the comprehensive environmental control of Weihe River in Shaanxi Province.展开更多
BLACK RICE OFYANGXIAN COUNTY The black rice produced in YangXianCounty is known as a precious food aroundthe world.The rice is black in colour andsimilar in size and shape to ordinary rice,buta little bit flatter. A l...BLACK RICE OFYANGXIAN COUNTY The black rice produced in YangXianCounty is known as a precious food aroundthe world.The rice is black in colour andsimilar in size and shape to ordinary rice,buta little bit flatter. A legend says that the rice seed wasdiscovered and bred by Zhang Qian,adistinguished diplomat of the Han Dynasty(206B.C.-A.D.220).One day he was readingon the banks of the River Xushui,whichforms,the a boundary between展开更多
By using 3s technology, the dynamic crop information system can be developed to meet the needs of sharing the agriculture information in Shaanxi Province. The dynamic crop information system can realize the query of c...By using 3s technology, the dynamic crop information system can be developed to meet the needs of sharing the agriculture information in Shaanxi Province. The dynamic crop information system can realize the query of crop information attribute and space, and the automatic acquirement, dynamic distribution and classification analysis of crop information. In this way, the whole process of real-time management of agricultural product with information and visualization can be carried out, which is to improve the level of agriculture information management automation in Shaanxi Province.展开更多
Maintenance of the ecosystem health of a river is of great importance for local sustainable development. On the basis of both qualitative and quantitative analysis of the influence of natural variations and human acti...Maintenance of the ecosystem health of a river is of great importance for local sustainable development. On the basis of both qualitative and quantitative analysis of the influence of natural variations and human activities on the ecosystem function of the Weihe River, the changes in major factors affecting its ecosystem health are deter- mined, which include: 1) Deficiency of environment flow: since the 1960s, the incoming stream flow shows an obvious decreasing tendency. Even in the low flow period, 80% of the water in the stream is impounded by dams for agriculture irrigation in the Baoji district. As a result, the water flow maintained in the stream for environmental use is very limited. 2) Deterioration of water quality: the concentrations of typical pollutants like Chemical Oxygen Demand (COD) and NH3-N are higher than their maximum values of the Chinese environmental quality standard. Very few fish species can survive in the River. 3) Deformation of water channels: the continuous channel sedimentation has resulted in the decrease in stream gradient, shrinkage of riverbed and the decline in the capability for flood discharge. 4) Loss of riparian vegetation: most riparian land has been occupied by urban construction activities, which have caused the loss of riparian vegetation and biodiversity and further weakened flood control and water purification functions.展开更多
基金Project of Xi’an Science and Technology Plan(23YXYJ0163)Education and Teaching Reform Research Project of Xi’an Medical University in 2023(S202311840061)+1 种基金First Affiliated Hospital of Xi’an Medical University of China(XYYFY-2023-01)2021 Xi’an Medical University University-Level Science and Technology Innovation Team(2021TD14)。
文摘To understand the current situation of institutional registration in Shaanxi Province after the implementation ofregistration system management in drug clinical trial institutions.Relevant information was collected on the“Announcement on the Accreditation of Drug Clinical Trial Institutions”issued by the National Medical Products Administration from 2005 to August 2022,the record management information system of drug and medical device clinical trial institutions,and the drug clinical trial registration and information publicity platform.A retrospective analysis was carried out in terms of institutional development,regional distribution,registered majors,principal investigators,and the number of drug clinical trials.After the implementation of institution registration,the number of drug clinical trial institutions in Shaanxi Province increased by 47.4%,884 principal investigators were registered,the number of registered majors expanded from 58 qualified to 117,and the professional scope increased by 50.4%.The policy of institution registration is conducive to promoting the rational use of medical resources and the development of drug clinical trial institutions and improving the healthy development of the pharmaceutical industry in Shaanxi Province.
文摘[Objective] The aim was to explore eco-economy in ecological fragile region with Wuqi County in Shaanxi Province as an example. [Method] Eco-economy development and major environmental problems in Wuqi County in Shaanxi Province were researched based on local social and economic conditions, population of impoverished people and environment vulnerability. [Result] The areas with vulnerable environment and backward economy should establish a virtuous circle between economy and environment and a sustainable model of economic development. [Conclusion] It is significant to change the severe situation of environment deterioration and to promote ecological civilization.
基金the National Natural Science Foundation of China(40771019)the National Natural Science Foundation of Shaanxi Province,China(2007D16).
文摘The Loess Plateau in northern Shaanxi Province of China covers Yulin, Yan'an, and Tongchuan cities mainly. The kind of physiognomy is complicated and various, including the transitional region of the sand and wind, the hilly-gully fragile region, the pimple mound region from North to South. Large-scale land reclamation projects that are severely affecting these ecosystems have been implemented. In this paper, we reported an investigation to the changes in land use and ecosystem services on the Loess Plateau in northern Shaanxi Province from 1978 to 2000. We used three LANDSAT TM and/or ETM data sets to estimate the changes in the size of five land-cover/land-use categories, and we also used previously published value coefficients to estimate the changes in the value of ecosystem services delivered by each land category. Finally, we ranked the contribution of various ecosystem functions to the overall value of the ecosystem services, we have estimated that the annual value of the ecosystem services is 56.95 billon RMB yuan in the Loess Plateau in northern Shaanxi Province in 2000. In the region, from 1978 to 2000, the economic value of the fixing carbon was higher, the economic value of water conservation was the lowest, but the economic value of the NPP, fixing carbon, and supplying oxygen accounted for above ninety percent of the total value, obviously the vegetation created the biggest ecosystem service value. We can conclude that future land-use policy formulation should give precedence to the conservation of these ecosystems over uncontrolled reclamation, and that further land reclamation should be based on rigorous environmental impact analyses.
基金National Natural Science Foundation of China, No.40371003 Ministry of Education of China, No.01158 Master Research Project of Shaanxi Normal University
文摘Using the theory and method of the ecological footprint, and combining the changes of regional land use, resource environment, population, society and economy, this paper calculated the ecological footprint, ecological carrying capacity and ecological surplus/loss in 1986-2002 on the Loess Plateau in northern Shaanxi Province. What is more, this paper has put forward the concept of ecological pressure index, set up ecological pressure index models, and ecological security grading systems, and the prediction models of different ecological footprints, ecological carrying capacity, ecological surplus and ecological safety change, and also has assessed the ecological footprint demands of 10,000 yuan GDE The results of this study are as follows: (1) the ecological carrying capacity in northern Shaanxi shows a decreasing trend, the difference of reducing range is the fastest; (2) the ecological footprint appears an increasing trend; (3) ecological pressure index rose to 0.91 from 0.44 during 1986-2002 on the Loess Plateau of northern Shaanxi with an increase of 47%; and (4) the ecological security in the study area is in a critical state, and the ecological oressure index has been increasing rapidlv.
基金supported by the national natural science foundation (41672012, 41688103)
文摘A new ootype collected from the Upper Cretaceous Lijiacun Formation in the Shangdan Basin,Shaanxi Province is described in this paper. Based on general external shape, size, eggshell thickness and honeycomb-like eggshell microstructure, eggs are referable to the oofamily Faveoloolithidae. Compared with other members of Faveoloolithidae, specimens described in this paper show special characteristics:adjacent pores are usually separated by two eggshell units between which often develop interspaces;columnar eggshell units are relatively closely arranged in radial view. According to these characteristics,we erect a new oogenus and a new oospecies: Duovallumoolithus shangdanensis oogen. et oosp. nov. The new discovery expands the diversity of Faveoloolithidae.
基金Supported by Knowledge Innovation Project of Chinese Academy of Sciences (No. KZCX3-SW-333-02)
文摘Efficiency and sustainability of grain production are now important in China. In this study, the grain production systems of Jiangsu and Shaanxi Provinces were compared, to analyze their efficiency and sustainability in terms of utilization of natural resources, inputs of purchased energy and materials, and outputs. Flows of energy and materials between environment and human society were identified, and the natural and human work involved in generating inputs as materials or energy were valued in terms of equivalent amount of solar energy required for their production using emergy method. The results showed environmental resources were continually playing a less important role in the systems, when inorganic subsidiary emergy inputs increased drastically while organic ones decreased or increased little. Deterioration of input emergy structure affected the systems′ efficiency and sustainability,resulting in emergy investment ratios and environmental loading ratios increasing while yield ratios and sustainability indices decreasing. In general, efficiency and sustainability of grain production in Jiangsu are worse than those in Shaanxi. This analysis also suggested that inorganic subsidiary emergy should be introduced properly, and peasants in Jiangsu should utilize natural conditions wisely while those in Shaanxi pay enough attention to soil and surface water conservation.
基金This study was funded by the survey projects initiated by the China Geological Survey(DD20189220,DD20211317,and 1212010634713).
文摘This study aims to investigate the mechanisms and health risks of fluoride enrichment in groundwater in the Loess Plateau,China.By taking Dali County,Shaanxi Province,China as an example,this study obtains the following results through field investigation and the analyses of water,soil,and crop samples.(1)The groundwater can be divided into two major types,namely the Quaternary pore-fissure water and Karst water.The Karst area and sandy area have high-quality groundwater and serve as the target areas for optional water supply.The groundwater in the study area is slightly alkaline and highly saline.Meanwhile,high-fluoride groundwater is mainly distributed in the loess and river alluvial plains in the depression area of the Guanzhong Basin and the discharge areas of the groundwater,with the highest fluoride concentration exceeding seven times the national standard.(2)Fluoride in groundwater mainly originates from a natural source and human activities.The natural source refers to the fluoride-bearing minerals in rocks and soil,and the fluoride from this source is mainly controlled by natural factors such as climate,geologic setting,pH,specific hydrochemical environment,ion exchange,and mineral saturation.Human activities in modern life can be further divided into industrial and agricultural sources primarily.(3)The health risks of fluoride contamination are very high in the Loess Plateau,especially for children compared to adults.Meanwhile,the risks of fluoride exposure through food intake are higher than those through drinking water intake.The authors suggest selecting target areas to improve water supply and ensure the safety of drinking water in the study area.Besides,it is necessary to plant crops with low fluoride content or cash crops and to conduct groundwater treatment to reduce the fluoride concentration in drinking water.These results will provide a theoretical basis for safe water supply in the faulted basin areas in the Loess Plateau.
基金supported by the grant of the Science and Technology Research and Development of Shaanxi Province[No.2012K16-12-03]
文摘This study was conducted to define the taxonomic status of Spermophilus in the plague area of Dingbian County in Shaanxi Province,China,through the two-factor variance analysis of morphological characteristics,DNA barcoding,and chromosome karyotype analysis.
基金This paper represents partial results of a major project(No,49290100)supported by the National Natural Science Foundation of China.
文摘The Baguamiao gold deposit in Fengxian County, Shaanxi Province, is a recentlyexplored super-large gold ore deposit. A comprehensive and deep-going study has revealedthat it is a polygenetic deposit: early-stage mineralization due to shearing, middle-stagemineralization due to hydrothermal alteration, and late-stage mineralization due toweathering, leaching and concentration at shallow depths. Shearing played a dominant role inthe formation of gold orebodies.
基金Supported by National Science and Technology Support Plan Project,China ( 2007BAC03A01)
文摘[ Objective] The research aimed to study change characteristics and formation cause of summer precipitation abnormality in Loess Plateau of northern Shaanxi Province. [ Method] Based on summer precipitation data at 15 observation stations in Loess Plateau of northern Shaanxi Province and NCEP/NCAR dataset from 1961 to 2008, change characteristics of summer precipitation in the region were investigated by using linear trend estimation and composite analysis. [Result] Summer rainfall had decrease trend in most parts of northem Shaanxi Province, but had increase trend in western and southern regions. The interannual and interdecadal variations were obvious. It had a large amount of precipitation from the mid- 1970s to the mid-1990s, while summer rainfall had decrease trend after the mid-1990s and increase trend in recent years. In wet years, it was a large positive anomaly zone from western Ural Mountains to northem Lake Baikal at middle and high latitudes, indicating that there was a blocking high over the Ural Mountains, while it was negative anomaly zone from northern Okhotsk Sea to Lake Baikal. From Northwest Pacific Ocean to Bo- hal Sea Bay and North China, it was a wide range of significant positive anomaly zone, which was favorable for Westem Pacific subtropical high ex- tending westward and northward. The analysis in dry years showed opposite circulation configuration. It was " -, +, -" wave train distribution in middle and high latitudes and positive anomaly zone along the Sea of Okhotsk. Western Pacific subtropical high was also by south and east. Major water vapor was from southeast direction in wet years, and abundant water vapor caused more summer rainfall in northern Shaanxi. In dry years, water vapor was from westerly tuming southerly flow. It was weaker and by east. [ Conclusion] The research provided reference for reasonable utilization of summer precipitation in the zone.
基金Supported by the Fundamental Research Funds for the Central Universities,CHD(300102129201)the Nat ural Science Basic Research Plan in Shaanxi Province of China(2018JM1011)the National Natural Science Foundation of China(11701041)。
文摘Objectives Firstly,according to the characteristics of COVID-19 epidemic and the control measures of the government of Shaanxi Province,a general population epidemic model is es-tablished.Then,the control reproduction number of general population epidemic model is obtained.Based on the epidemic model of general population,the epidemic model of general population and college population is further established,and the control reproduction number is also obtained.Methods For the established epidemic model,firstly,the expression of the control reproduc-tion number is obtained by using the next generation matrix.Secondly,the real-time reported data of COVID-19 in Shaanxi Province is used to fit the epidemic model,and the parameters in the model are estimated by least square method and MCMC.Thirdly,the Latin hypercube sampling method and partial rank correlation coefficient(PRCC)are adopted to analyze the sensitivity of the model.Conclusions The control reproduction number remained at 3 from January 23 to January 31,then gradually decreased from 3 to slightly greater than 0.2 by using the real-time reports on the number of COVID-19 infected cases from Health Committee of Shaanxi Province in China.In order to further control the spread of the epidemic,the following measures can be taken:(i)reducing infection by wearing masks,paying attention to personal hygiene and limiting travel;(i)improving isolation of suspected patients and treatment of symptomatic individuals.In particular,the epidemic model of the collge population and the general population is estab-lished,and the control reproduction number is given,which will provide theoretical basis for the prevention and control of the epidemic in the colleges.
文摘Studies on rocks and ores of Jianchaling ore deposit, southern Shaanxi, show that REE patterns in the ores clearly differ from that in ultrabasic and acidic rocks. The REE pattern in Ni ore is similar to that in Au ore and is characterized by typical enrichment in LREE and sharp negative Eu and Ce anomalies, indicating that Ni ore and Au ore were formed from the same hydrothermal solution. δ Eu and δ Ce variations reflect that Ni ore is formed at higher temperature and relative reduction environment, and Au ore at lower temperature and relative oxidation environment. The characteristics imply that the ore forming materials were derived from the ultrabasic rock and the hydrothermal solution is a post magmatic acidic solution.
文摘Triplet surveys were conducted in the city of Xi'an and two villages (one in the vicinity and the other at a distance) in Shaanxi fuvince in China in October-November (when agricultural activitis were low), 1997, to elucidate nutrient intakes with a focus on possible urban-rural differences. Total food duplicate samples were collected from non-smoking and non-habitually dhnking adult healthy women (ahout 50 subjects per site and 149 in total). The nutrient intakes were estimated from the weight of food items in reference to national food composition tables. On average, the women took 1873 kcal energy, 54 g protein and 37 g lipid per day, with a lipid eneny ratio of 18.4%. Both excess and insufficient energy intake was observed as a result of food intake analysis and body mass index determination. With regard to minor nutrient intakes, insufficiency was serious in the case of calcium, vitamin A and vitamin B2, but not with iron. Whereas dependency on plant foods for sources of energy and protein was common to the three regions, Xi' an people consumed more animal foods than those in the villages. Intake of fish and shellfish was quite low throughout the three regions. Among the four types of cereals, wheat was consumed most substantially in the three regions and in three meals (except for the village where people essentially did not take lunch in reflection of low agricultural activities), whereas rice was consumed more in Xi'an than in the two villages. Maize consumption was higher in the two villages (especially for breakfast) than in the city.In contrast, foxtail millet (although in small amounts) was taken primarily in Xi'an and ouly at the time of breakfast.
文摘Situated in the Henan-Shaanxi fault-uplift area on the southern margin of the Sino-Korean Paraplatform,the jinduicheng porphyry molybdenum deposit is the most important molybdenum producer in China.During Yenshanian the Jinduicheng granite porphyry was emplaced in metaspilite of the Proterozoic XiongerGroup,controlled by a NW trending fault Mineral compositions are mainly quartz (25-40%),microclineand microcline perthite(27-40%)and plagioclase(An8-14-,14-32%),associated with minor biotite andmuscovite,and phenocrysts are made up of K-feldspar,quartz and phagioclase.Accessory minerals includemagmatite,apatite and zircon,The porphyry contains SiO2 73.83% and K2O+Na2O 8.06%(withK2O/Na2O ratio being 1.82),beloning to the calc-alkaline series Mineralization occurs in the porphyry body and biotitized and hornfelsized spilite Within the exocontactzone.The maximum depth of mineralization reaches 1000 meters below the surface.According to mineralassemblage,ore veins are classified into five types:(l) Pyrite-quartz;(2) Pyrite-K-feldspar-quartz; (3)pyrite-molybdenite-quartz:(4) pyrite-molybdenite-K-feldspar-quartz;and(5) Muscovitefluorite-pyrite-molybdenite-quartz. As the most important economic molybdenum mineral,molybdenite occurs in various forms.Wall-rockalterations show a gross zonation of K-feldspathization-greisenization→silicification→propylitization fromthe porphyry outwards,of which silicification is most intense and has close genetic relationship with Momineralization. Fluid inclusion studies yield homogeneous temperatures ranging from 240to240℃,with the main stagebetween 400 and 300℃.Gas inclusions frequently coexist with multiphase inclusions containing suchdaughter minerals as halite,sylvite,molybdenite and K-feldspar.Under moderate-high temperatures,lowerfo2,high fs2 and weak。acidity conditions,boiling of ore-forming fluids is prerequisite for the Precipitation ofmolybdenite. Sulfur,oxygen and carbon isotopic compositions suggest that at the high temperature stage(450℃)magmatic water is dominant and at the main ore-forming stage a mixture of mixture of magmatic water and meteoricwater is expected.At the late stage,the mixture is predominated by meteoric water.Sulfur and molybdenumare mostly of magmatic origin.
文摘Shaanxi is situated in China’s hinterland,with a total area of 205,600 squarekilometers and a population of 34.8million. The province is composed of 10cities and prefectures (including the sixprovincial cities of Xi’an, Baoji, Xianyang,Tongchuan, Weinan and Jiangzhong, andfour prefectures of Ankang, Shanluo, Yan’anand Yulin), 107 county-level cities, countiesand districts, with Xi’an as the provincialcapital. The average temperature of theprovince is 8 - 16 ℃, average rainfall 674mm, and frost-free period 150 - 270 days. Inthe north lies the Huangtu Plateau, in thesouth is Mount Qingba, and in the centre isthe Guanzhong Plain. Shaanxi is abundant with
文摘[ Objective] The study aimed to analyze the changing trends of surface water quality and their causes of Weihe River in Shaanxi Province over past ten years. [ Method] Based on the available monitoring data of water quality of Weihe River in Shaanxi Province from 2001 to 2010, the changing trends of surface water quality of Weihe River in Shaanxi Province during recent ten years were assessed by using the assessment method of surface water quality according to the Assessment Method of Surface Water Quality and Environmental Quality Standards for Surface Water (GB 3838-2002). Moreover, the possible reasons for the trends were also proposed. [ Result] From 2001 to 2010, there was a relatively decrea- sing trend of water pollution in Weihe River due to the considerable decline in the content of the main environmental pollutants like permanganate in- dex, 5-day biochemical oxygen demand ( BOD5 ), ammonia nitrogen, oil and volatile phenol. Meanwhile, the comprehensive pollution index fell by 62.7%, eliminating Weihe River's black and stink on schedule. However, the overall surface water quality of Weihe River was still polluted heavily in each year, and the pollution control of Xi'an section should be paid more attention to. [ Conclusion] The research could provide scientific refer- ences for the comprehensive environmental control of Weihe River in Shaanxi Province.
文摘BLACK RICE OFYANGXIAN COUNTY The black rice produced in YangXianCounty is known as a precious food aroundthe world.The rice is black in colour andsimilar in size and shape to ordinary rice,buta little bit flatter. A legend says that the rice seed wasdiscovered and bred by Zhang Qian,adistinguished diplomat of the Han Dynasty(206B.C.-A.D.220).One day he was readingon the banks of the River Xushui,whichforms,the a boundary between
文摘By using 3s technology, the dynamic crop information system can be developed to meet the needs of sharing the agriculture information in Shaanxi Province. The dynamic crop information system can realize the query of crop information attribute and space, and the automatic acquirement, dynamic distribution and classification analysis of crop information. In this way, the whole process of real-time management of agricultural product with information and visualization can be carried out, which is to improve the level of agriculture information management automation in Shaanxi Province.
基金Acknowledgements This study is jointly supported by the National Natural Science Foundation of China (Grant Nos. 51079123 and 51379175), Program for New Century Excellent Talents in University (No. NCET-11-1045), Technology Foundation for Selected Overseas Chinese Scholar (2011 -12-09), Scientific Research Foundation for Returned Scholars (2010-1174), and Natural Science Foundation of Shaanxi Province (Grant No.12k798).
文摘Maintenance of the ecosystem health of a river is of great importance for local sustainable development. On the basis of both qualitative and quantitative analysis of the influence of natural variations and human activities on the ecosystem function of the Weihe River, the changes in major factors affecting its ecosystem health are deter- mined, which include: 1) Deficiency of environment flow: since the 1960s, the incoming stream flow shows an obvious decreasing tendency. Even in the low flow period, 80% of the water in the stream is impounded by dams for agriculture irrigation in the Baoji district. As a result, the water flow maintained in the stream for environmental use is very limited. 2) Deterioration of water quality: the concentrations of typical pollutants like Chemical Oxygen Demand (COD) and NH3-N are higher than their maximum values of the Chinese environmental quality standard. Very few fish species can survive in the River. 3) Deformation of water channels: the continuous channel sedimentation has resulted in the decrease in stream gradient, shrinkage of riverbed and the decline in the capability for flood discharge. 4) Loss of riparian vegetation: most riparian land has been occupied by urban construction activities, which have caused the loss of riparian vegetation and biodiversity and further weakened flood control and water purification functions.