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Sample records for altun northwest china

  1. Alpine glacier change in the Eastern Altun mountains of Northwest China during 1972-2010.

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    Xinyang Yu

    Full Text Available Accurately mapping and monitoring glacier changes over decades is important for providing information to support sustainable use of water resource in arid regions of northwest China. Since 1970, glaciers in the Eastern Altun Mountains showed remarkable recession. Further study is indispensable to indicate the extent and amplitude of glacial change at basin and individual glacier scale. In this study, spatiotemporal glacier changes referring to the year 1972, 1990, 2000 and 2010 were studied for the Eastern Altun Mountains using Landsat MSS/TM/ETM+ images and glacier volume-area scaling. The results demonstrated that the total area and volume of glaciers in EAMs decreased significantly by 10.70±0.57 km² (19.56±10.41% and 0.61±0.03 km³ (23.19±11.40% during 1972-2010, respectively. More than half of the total receding area occurred during 1990-2000, primarily due to higher temperature increasing. However, varied response of individual glaciers indicated that glacier change was also affected by glacier dynamics, which was related to local topography. In addition, five glaciers unrecorded in the glacier inventory of China were reported in this study.

  2. Three Alkali-Rich Intrusive Rock Belts Newly Discovered in the Mt. Kunlun-Mt. Altun Region, Xinjiang, China

    Institute of Scientific and Technical Information of China (English)

    朱笑青; 王元龙; 毕华; 王中刚

    2002-01-01

    The newly discovered three alkali-rich intrusive rock belts in the Mt. Kunlun Mt.Altun region of southern Xinjiang are the Lapeiquan-Yitunbulak alkali-rich intrusive rock belt,the Gez-Taxkorgan alkali-rich intrusive rock belt and the Beilisai-Abulash alkali-rich intrusive rock belt. The former two belts were formed during the Yanshanian period, and the third one was formed during the Himalayan period, which is the youngest alkali-rich intrusive rock belt in China. The discovery of the alkali-rich intrusive rock belts is of great significance in shedding light on the history of tectono-magmatic activities in this region.

  3. Three Alkali—Rich Intrusive Rock Belts Bewly Discovered in the Mt.Kunlkun—Mt.Altun Region,Xinjiang,China

    Institute of Scientific and Technical Information of China (English)

    朱笑青; 王元龙; 等

    2002-01-01

    The newly discovered three alkali-rich intrusive rock belts in the Mt.Kunlun Mt.Altun region of southern Xinjiang are the Lapeiquan-Yitunbulak alkali-rich intrusive fock belt, the Gez-Taxkorgan alkali-rich intrusive rock belt and the Beeilisai-Abulash alkali-rich intrusive rock belt.The former two belts were formed during the Yanshanian period,and the third one was formed during the Himalayan period,which is the youngest alkali-rich intrusive rock belt in China.The discovery of the alkali-rich intrusive rock belts is of great significance in shedding light on the history of tectono-magmatic activities in this region.

  4. Bashikaogong-Shimierbulake granitic complex,north Altun,NW China: Geochemistry and zircon SHRIMP ages

    Institute of Scientific and Technical Information of China (English)

    WU; Cailai; YAO; Sunzhi; ZENG; Lingsen; YANG; Jingsui; Joseph; L.Wooden; CHEN; Songyong; Frank; K.Mazdab

    2006-01-01

    The Bashikaogong-Shimierbulake granitoid complex is about 30 km long and 2-6 km wide,with an area of 140 km2,located at the north margin of the Bashikaogong Basin in the north Altun terrain.It intruded into schist,metapelite and metatuff of Precambrian ages.This granitoid complex consists of darkish quartz diorite,grey granite,pink granite and pegmatite.Geochemically,the quartz diorite has I-type granite affinity and belongs to Calc-alkaline sereies,and the other granites have S-type affinity and to high-K calc-alkaline series.Zircon SHRIMP U-Pb dating shows that the quartz diorite has a bigger age than those of other granites,which is 481.6±5.6 Ma for quartz diorite,437.0±3.0 Ma-433.1±3.4 Ma for grey granite and 443±11 Ma-434.6±1.6 Ma for pink granite,respectively.Combined with regional geology,we think that the quartz diorite formed in tectonic environment related to oceanic crust subduction and the granites in post-collision.

  5. The distribution, geochronology and geochemistry of early Paleozoic granitoid plutons in the North Altun orogenic belt, NW China: Implications for the petrogenesis and tectonic evolution

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    Meng, Ling-Tong; Chen, Bai-Lin; Zhao, Ni-Na; Wu, Yu; Zhang, Wen-Gao; He, Jiang-Tao; Wang, Bin; Han, Mei-Mei

    2017-01-01

    Abundant early Paleozoic granitoid plutons are widely distributed in the North Altun orogenic belt. These rocks provide clues to the tectonic evolution of the North Altun orogenic belt and adjacent areas. In this paper, we report an integrated study of petrological features, U-Pb zircon dating, in situ zircon Hf isotope and whole-rock geochemical compositions for the Abei, 4337 Highland and Kaladawan Plutons from north to south in the North Altun orogenic belt. The dating yielded magma crystallization ages of 514 Ma for the Abei Pluton, 494 Ma for the 4337 Highland Pluton and 480-460 Ma for the Kaladawan Pluton, suggesting that they are all products of oceanic slab subduction because of the age constraint. The Abei monzogranites derived from the recycle of Paleoproterozoic continental crust under low-pressure and high-temperature conditions are products of subduction initiation. The 4337 Highland granodiorites have some adakitic geochemical signatures and are sourced from partial melting of thickened mafic lower continental crust. The Kaladawan quartz diorites are produced by partial melting of mantle wedge according to the positive εHf(t) values, and the Kaladawan monzogranite-syenogranite are derived from partial melting of Neoproterozoic continental crust mixing the juvenile underplated mafic material from the depleted mantle. These results, together with existing data, provide significant information about the evolution history of oceanic crust subduction during the 520-460 Ma. The initiation of subduction occurred during 520-500 Ma with formation of Abei Pluton; subsequent transition from steep-angle to flat-slab subduction at ca.500 Ma due to the arrival of buoyant oceanic plateaus, which induces the formation of 4337 Highland Pluton. With ongoing subduction, the steep-angle subduction system is reestablished to cause the formation of 480-460 Ma Kaladawan Pluton. Meanwhile, it is this model that account for the temporal-spatial distribution of these early

  6. China Northwest Architectural Design & Research Institute

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    China Northwest Architectural Design & Research Institute,founded by the state on June 1, 1952 is the first and largest architectural design institute in northwest China. For over 50 years, Northwest Institute has gradually established itself as a renowned and comprehensive design institute. It is staffed by a team of outstanding engineering design specialists able to undertake various architectural design projects from home and abroad.

  7. Characteristics of Recent Horizontal Crustal Movement and Tectonic Deformation in the Northwest China Region

    Institute of Scientific and Technical Information of China (English)

    Liu Wenyi; Wang Shuangxu; Wang Wenping; Zhang Xiaoliang; Cui Duxin; Xue Fuping

    2006-01-01

    Making use of observation data of GPS in the Northwest China region and infrared distancemeasurements crossing the Qilian-Longshoushan fault zone up to 2004, aided by the least square collocation and inversion of negative dislocation model for the boundaries of elastic blocks and the singular force-source, the dynamic evolution features of deformation and strain fields before and after the Ms = 8. 1 earthquake on the west of Kunlun Mountains Pass,especially the recent tectonic deformation and stress field status three years after this earthquake are studied. The possible regions or segments of active blocks and their boundaries reflecting accumulation background of high strain energy of producing earthquakes over middle magnitude, are obtained, as well as the potential epicenter. The results show that after short-term relaxation and adjustment in the northern margin of Qinghai-Xizang (Tibet) block after the Ms = 8. 1 earthquake, the main control action of background field of northeastward pushing of Indian plate is now recovering. Moreover, the following regions are found to have the background of high strain energy accumulation. They are the middle segment of the northern Tianshan fault zone and its meeting region with the western segment, the middle and western segments of southern Tianshan fault zone and the meeting region with Western Kunlun fault zone, the middle segment of Altun fault, the middle-eastern segment of Qilianshan fault zone and its meeting region with Haiyuan fault, the meeting region of northern margin fault of west Qinling Range and the southeastward expanding line of Zhuanglanghe fault; The Linze and Haiyuan areas also see accumulation of strain energy to some degree.

  8. Northwest China covered by 750-kV power grid

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Being abundant in hydropower, coal, wind energy and solar energy etc., Northwest China is an important energy base with great potential. In recent years, along with the vigorous development of the energy base, the

  9. The Altun Fault: Its Geometry, Nature and Mode of Growth

    Institute of Scientific and Technical Information of China (English)

    崔军文; 李莉; 杨经绥; 岳永军; 李朋武; 张建新; 陈文

    2001-01-01

    The Altun (or Altyn Tagh) fault displays a geometry of overlapping of linear and arcuate segments and shows strong inhomogeneity in time and space. It is a gigantic fault system with complex mechanical behaviours including thrusting, sinistral strike slip and normal slip. The strike slip and normal slip mainly occurred in the Cretaceous–Cenozoic and Plio–Quaternary respectively, whereas the thrusting was a deformation event that has played a dominant role since the late Palaeozoic (for a duration of about 305 Ma). The formation of the Altun fault was related to strong inhomogeneous deformation of the massifs on its two sides (in the hinterland of the Altun Mountains contractional deformation predominated and in the Qilian massif thrust propagation was dominant). The fault experienced a dynamic process of successive break-up and connection of its segments and gradual propagation, which was synchronous with the development of an overstep thrust sequence in the Qilian massif and the uplift of the Qinghai-Tibet plateau. With southward propagation of the thrust sequence and continued uplift of the plateau, the NE tip of the Altun fault moved in a NE direction, while the SW tip grew in a SW direction.

  10. Community Service, Educational Performance and Social Responsibility in Northwest China

    Science.gov (United States)

    Luo, Renfu; Shi, Yaojiang; Zhang, Linxiu; Liu, Chengfang; Li, Hongbin; Rozelle, Scott; Sharbono, Brian

    2011-01-01

    The main goal of this paper is to analyse the effect of high school scholarships tied to community service on the development of secondary school students in Northwest China. Using data from three rounds of surveys of thousands of students in 298 classes in 75 high schools in Shaanxi province, the paper documents the implementation of the…

  11. Two new species of Stemphylium from Northwest China

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    During surveys of hyphomycetes from the Northwest of China, two undescribed taxa of Stemphylium were discovered from diseased leaves of Malus sieversii and Pyrus sinkiangensis in Sinkiang Provence, which are described as S. mali and S. pyrinum. The two species differ from similar species morphologi...

  12. Challenges and Improvements of Wind Power Dispatch in Northwest China

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Besides common characteristics of wind power, there are some special characteristics in China power system, including large-scale, long distance transmission and lack of flexible regulating power sources. These special characteristics make power dispatch more challenging in China. Many studies have been carried out and some improvements are presented including wind power monitoring and control as well as evaluation of wind power integration capabilities. As a demonstration project, the technologies are integrated into the energy management system and are implemented in the Northwest China power system. They provide effective measures for wind power dispatch in the grid.

  13. Appropriate Strategies for Rural Houses In Northwest China

    Institute of Scientific and Technical Information of China (English)

    HE Quan; LIU Jia-ping; LU Xiao-hui; YANG Liu

    2009-01-01

    To avoid the old road of urban development with high consumption and high pollution,this paper took the houses in a village near Yinchuan(a typical city of Northwest China)as an exemplary proiect to explore the appropriate strategies in the arid cold climate for the sustainable devdopment in rural undeveloped areas Northwest China.Firstly,all houses were designed according to the principles of passive solar heating.Second-ly,optimized biomass energy technologies such as biogas pit and straw gasification stove were utilized for cooking or heating.Last but not the least important,the ecological building materials such as earth,straw bale,fly ash were used to construct houses,which improves the indoor thermal comfort and meanwhile lowers the negative impact on the environment.Low costs,easy accessibility and habitants'inclination were taken into account in the process of design.

  14. Estimation of regional evapotranspiration over Northwest China using remote sensing

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    It is a very complicated problem to estimate evapotranspiration (ET) over a large area of land surface. In this paper, the evapotranspiration estimation models for dense vegetation and bare soil are presented, based on the information of parameters like vegetation cover-degree and surface albedo. Combined with vegetation cover-degree data, a model for regional evapotranspiration estimation over the heterogeneous landscape is derived. Through a case study using remote sensing data over Northwest China, the accuracy of the model for regional evapotranspiration estimation is checked. The result shows that the accuracy of the model is satisfactory. The features of evapotranspiration over Northwest China are also discussed with the application of the model.

  15. A Miocene ostrich fossil from Gansu Province, northwest China

    Institute of Scientific and Technical Information of China (English)

    HOU Lianhai; ZHOU Zhonghe; ZHANG Fucheng; WANG Zhao

    2005-01-01

    @@ A pelvic skeleton, recognized as a large terrestrial bird in the field, was recently collected by our paleomammalogist colleagues from the Institute of Vertebrate Paleontology and Paleoanthropology from the late Miocene sandy mudstones in the Linxia Basin in Gansu Province, northwest China. We have further referred this bird to as an early representative of ostrich. Ostrich fossils usually coexisted with the famous Hipparion Fauna from the Miocene to Pliocene.

  16. Exiled by Definition:The Salar of Northwest China

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    David SG Goodman

    2005-03-01

    Full Text Available The reform of state socialism came relatively late to Qinghai Province in the Northwest of the People’s Republic of China. One of Qinghai’s most dynamic groups in the social leadership of reform has been the Salar. The Salar were one of the officially recognized nationalities identified in the People’s Republic of China during the 1950s. A relatively small group of some 100,000 currently live along the upper reaches of the Yellow River, on the borders of Qinghai and Gansu Provinces. The Salar are characterised by their commitment to both Islam and China, and by their belief that they live in permanent exile, though there is considerable uncertainty about their origins. The evidence of recent research in Qinghai suggests the perspective of being Chinese citizens, yet a people in exile, significantly shapes recent Salar social and economic activism.

  17. Climate Change Impacts and Adaptation Strategies in Northwest China

    Institute of Scientific and Technical Information of China (English)

    ZHAO Hong-Yan; LIU Cai-Hong; LI Yan-Chun; FANG Jian-Gang; LI Lin; LI Hong-Mei; ZHENG Guang-Fen; DENG Zhen-Yong; DONG An-Xiang; GUO Jun-Qin; ZHANG Cun-Jie; SUN Lan-Dong; ZHANG Xu-Dong; LIN Jing-Jing; WANG You-Heng; FANG Feng; MA Peng-Li

    2014-01-01

    Climate change resulted in changes in crop growth duration and planting structure, northward movement of planting region, and more severe plant diseases and insect pests in Northwest China. It caused earlier seeding for spring crop, later seeding for autumn crop, accelerated crop growth, and reduced mortality for winter crop. To adapt to climate change, measures such as optimization of agricultural arrangement, adjustment of planting structure, expansion of thermophilic crops, and development of water-saving agriculture have been taken. Damaging consequences of imbalance between grassland and livestock were enhanced. The deterioration trend of grassland was intensified; both grass quantity and quality declined. With overgrazing, proportions of inferior grass, weeds and poisonous weeds increased in plateau pastoral areas. Returning farmland to grazing, returning grazing to grassland, fence enclosure and artificial grassland construction have been implemented to restore the grassland vegetation, to increase the grassland coverage, to reasonably control the livestock carrying capacity, to prevent overgrazing, to keep balance between grassland and livestock, and to develop the ecological animal husbandry. In Northwest China, because the amount of regional water resources had an overall decreasing trend, there was a continuous expansion in the regional land desertification, and soil erosion was very serious. A series of measures, such as development of artificial precipitation (snow), water resources control, regional water diversion, water storage project and so on, were used effectively to respond to water deficit. It had played a certain role in controlling soil erosion by natural forest protection and returning farmland to forest and grassland. In the early 21st century, noticeable achievements had been made in prevention and control of desertification in Northwest China. The regional ecological environment has been improved obviously, and the desertification trend

  18. Fluorine emission from com-bustion of steam coal of North China Plate and Northwest China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    To study the amount of fluorine emission from the combustion of the steam coal (mainly Permo-Carbonif- erous coal) from the North China Plate and Northwest China, the fluorine contents of the coal, the fly ash and the cinder in high-temperature power stations as well as mid-low temperature power stations have been analyzed. This note provides a rough estimate of the total annual amount of fluorine emission as well as emission ratio from steam coal combustion in China. Our results show that by combustion of 1 t of Permo-Carboniferous coal (containing roughly 100 g fluorine), high-temperature power stations emit roughly 90 g fluorine into the atmosphere. The fluorine emission ratio of coal combustion in high-temperature power stations is about 96% and that in mid-low temperature power stations is about 78%. A total of 800 million tons of coal is burnt in China every year, and the coal comes mainly from Permo- Carboniferous deposite in the North China Plate and Northwest China coal mines. Taking the average fluorine content of the coal used at a low value of 100 mg/kg, the total annual fluorine emission from steam coal combustion into the atmosphere is estimated to be 66398 t.

  19. The Local Residents’ Concerns about Environmental Issues in Northwest China

    Directory of Open Access Journals (Sweden)

    Fanus A. Aregay

    2016-03-01

    Full Text Available This paper analyzes public awareness and perception about current issues of environmental and water resources in China in comparison to the socio-economic issues. The ranking, Likert scale, and ordered logit analysis were applied to data from 1773 sample residents in northwest China. The results show that the residents rank the degradation of the ecological environment and water resources as the most important issue, and education, political involvement, gender, employment, and residential location play significant roles in explaining the observed differences in concern. Of the possible environmental and water resource restoration policies, residents ranked water quantity and quality, agricultural and industrial water use, erosion control, vegetation restoration, wildlife habitat, animal brooding and migration services, biodiversity landscape, and eco-tourism from one to nine in order of importance, respectively. The results are relevant for policymaking and imply that environmental restoration is a high public demand. Welfare gains from investments in it would be higher or equal to gains from other socio-economic and livelihood activities. Thus, public policies must emphasize restoring and maintaining a sustainable ecological environment.

  20. Evaluation of mulched drip irrigation for cotton in arid Northwest China

    NARCIS (Netherlands)

    Wang, Z.; Jin, M.; Simunek, J.; van Genuchten, M.T.

    2014-01-01

    Field experiments were conducted in arid Southern Xinjiang, Northwest China, for 3 years to evaluate sustainable irrigation regimes for cotton. The experiments involved mulched drip irrigation during the growing season and flood irrigation afterward. The drip irrigation experiments included control

  1. Evaluation of mulched drip irrigation for cotton in arid Northwest China

    NARCIS (Netherlands)

    Wang, Z.; Jin, M.; Simunek, J.; van Genuchten, M.T.

    2014-01-01

    Field experiments were conducted in arid Southern Xinjiang, Northwest China, for 3 years to evaluate sustainable irrigation regimes for cotton. The experiments involved mulched drip irrigation during the growing season and flood irrigation afterward. The drip irrigation experiments included control

  2. Clinical characteristics of patients with gastroesophageal reflux disease in several centers of Northwest China

    Institute of Scientific and Technical Information of China (English)

    高麦仓

    2013-01-01

    Objective To investigate the clinical characteristics of gastroesophageal reflux disease (GERD) in several endoscopy centers of Northwest China.Methods From September 2008 to September 2009,a questionnaire survey was carried out in the endoscopy centers of four hospitals

  3. Response of Glaciers to Climate Change in Northwest China

    Science.gov (United States)

    Li, Z.; Wang, P.

    2015-12-01

    In Northwest China, an extremely dry region, more than 20,000 mountain glaciers are developed. Glacial melt water is vital for local water resources, ecosystem in the lower reaches, peoples' living and city development there. During the past several decades, due to climate warming, the most glaciers in NW China are in a state of rapid retreating. To obtain the general idea on response of glaciers in that region, Tianshan Glaciological Station, Chinese Academy of Sciences selected more than ten glaciers in six sub-regions along Altai Mountain, Tianshan and Qilian Mountain, respectively, doing in-situ observations. Based on field observation and remote sensing technique, this study has revealed that the area reductions in different regions range between 8.8%~34.2 % during the past four decades. The potential impact of the glacier recession on water resource in future will be spatially different. For the Tarim River, the glacier runoff is estimated to maintain its current level or increase somewhat in next 30~50 years. In the north slope of Tianshan, the glaciers with a size smaller than 1 km2 are most likely to be melted away in next 20~40 years, and those larger than 5 km2 are melting intensively. In eastern Xinjiang, because the number of the glaciers is small and also because the climate is extremely dry, the glacier retreating are causing the water shortage problem. For Ili River and Irtysh River, because they are dominant by snow melt runoff, the impact of the glacier shrinkage and temperature rise would be limited on the quantity of the river runoff, but significant on the annual distribution of the river runoff. For Qilian Mountains, glaciers are quite small. The vanishing of small glacier will have significant impact on local water resources in near future.

  4. [Donations after cardiac death kidney transplantation in northwest China].

    Science.gov (United States)

    Pan, Xiaoming; Xue, Wujun; Liu, Linjuan; Xiang, Heli; Ding, Chenguang; He, Shuqin; Ren, Li; Tian, Puxun; Ding, Xiaoming

    2014-03-01

    To explore the effect of donations after cardiac death (DCD) kidney transplant performed in northwest China and the measures for management of delayed graft function (DGF). In the period of 2011-2013, a total of 51 families of DCD donor gave their consent to organ donation by signing the informed consent with the help by a Red Cross Organization (ROC) coordinator, and 102 kidneys were retrieved by organ procurement organization (OPO) teams. Ninety-four operations of renal transplantation were carried out in our hospital. All the patients were followed-up and based on the occurrence of DGF after transplantation, they were divided into DGF group and non-DGF group for comparative studies. The success rate of donation after cardiac death was 29.3%, and the incidence of post-transplantation DGF was 27.7%. The 1-year human/kidney survival rate was 98.9%/95.7%. Within six months after the transplant, the values of eGFR in DGF group were significantly lower and serum creatinine significantly higher than those in non-DGF group (P0.05). The occurrence of DGF in LifePort mechanical perfusion cohorts was significantly lower than that in the simple cold preservation group (21.5% vs. 41.4%, Ptransplant is good despite a high incidence of early DGF, and we recommend the use of low-temperature mechanical perfusion for storage and transportation of DCD donor kidney.

  5. Pulsed strain release on the Altyn Tagh fault, northwest China

    Science.gov (United States)

    Gold, Ryan D.; Cowgill, Eric; Arrowsmith, J. Ramón; Friedrich, Anke M.

    2017-02-01

    Earthquake recurrence models assume that major surface-rupturing earthquakes are followed by periods of reduced rupture probability as stress rebuilds. Although purely periodic, time- or slip-predictable rupture models are known to be oversimplifications, a paucity of long records of fault slip clouds understanding of fault behavior and earthquake recurrence over multiple ruptures. Here, we report a 16 kyr history of fault slip-including a pulse of accelerated slip from 6.4 to 6.0 ka-determined using a Monte Carlo analysis of well-dated offset landforms along the central Altyn Tagh strike-slip fault (ATF) in northwest China. This pulse punctuates a median rate of 8.1+1.2/-0.9 mm /a and likely resulted from either a flurry of temporally clustered ∼Mw 7.5 ground-rupturing earthquakes or a single large >Mw 8.2 earthquake. The clustered earthquake scenario implies rapid re-rupture of a fault reach >195 km long and indicates decoupled rates of elastic strain energy accumulation versus dissipation, conceptualized as a crustal stress battery. If the pulse reflects a single event, slip-magnitude scaling implies that it ruptured much of the ATF with slip similar to, or exceeding, the largest documented historical ruptures. Both scenarios indicate fault rupture behavior that deviates from classic time- or slip-predictable models.

  6. Pulsed strain release on the Altyn Tagh fault, northwest China

    Science.gov (United States)

    Gold, Ryan D.; Cowgill, Eric; Arrowsmith, J. Ramón; Friedrich, Anke M.

    2017-01-01

    Earthquake recurrence models assume that major surface-rupturing earthquakes are followed by periods of reduced rupture probability as stress rebuilds. Although purely periodic, time- or slip-predictable rupture models are known to be oversimplifications, a paucity of long records of fault slip clouds understanding of fault behavior and earthquake recurrence over multiple ruptures. Here, we report a 16 kyr history of fault slip—including a pulse of accelerated slip from 6.4 to 6.0 ka—determined using a Monte Carlo analysis of well-dated offset landforms along the central Altyn Tagh strike-slip fault (ATF) in northwest China. This pulse punctuates a median rate of 8.1+1.2/−0.9 mm/a and likely resulted from either a flurry of temporally clustered ∼Mw 7.5 ground-rupturing earthquakes or a single large >Mw 8.2 earthquake. The clustered earthquake scenario implies rapid re-rupture of a fault reach >195 km long and indicates decoupled rates of elastic strain energy accumulation versus dissipation, conceptualized as a crustal stress battery. If the pulse reflects a single event, slip-magnitude scaling implies that it ruptured much of the ATF with slip similar to, or exceeding, the largest documented historical ruptures. Both scenarios indicate fault rupture behavior that deviates from classic time- or slip-predictable models.

  7. The Efiect of Northwest the Muslim population in China's Residences by Various Cultures

    Institute of Scientific and Technical Information of China (English)

    Li Yiyong

    2009-01-01

    By analyzing geographical conditions,geographical features of the northwest inhabited areas, religious factors simpact on the Muslim population in China Vernacular Architecture as well as Han culture's impact on it,the thesis expounded the unique artistic style of Musl im population in China residential construction.

  8. Assessing Dryland Ecosystem Services in Xinjiang, Northwest China

    Science.gov (United States)

    Siew, T. F.; Brauman, K. A.; Zuo, L.; Doll, P. M.

    2014-12-01

    Dryland ecosystems, including grassland, forest, and irrigated cropland, cover about 41% of earth's land area and are inhabited by over two billion people. In drylands, particularly arid and semiarid areas, the production of ecosystem services is primarily constrained by freshwater availability. Often, water allocated to production by one ecosystem or of one ecosystem service negatively impacts other ecosystems or ecosystem services (ESS). The challenge is to determine how much water should be allocated to which ecosystems (natural and manmade) such that multiple ESS are maximized, thus improving overall well-being. This strategic management decision must be supported by knowledge about spatial and temporal availability of water and its relationship to production (location and scale) of ESS that people receive. We assess the spatial and temporal relationships between water availability and ESS production in Xinjiang, Northwest China. We address four questions: (1) What services are produced by which ecosystems with water available? (2) Where are these services produced? (3) Who uses the services produced? (4) How the production of services changes with variability of water available? Using existing global, national, and regional spatial and statistical data, we assess food, fiber, livestock, and wood production as well as unique forest landscapes (as a proxy for aesthetic appreciation and habitats for unique animals and plants) and protection from dust storms. Irrigation is necessary for crop production in Xinjiang. The production of about 4.2 million tons of wheat and 500,000 tons of cotton requires more than 2 km3 of water each year. This is an important source of food and income for local residents, but the diverted water has negative and potentially costly impacts on downstream forests that potentially provide aesthetic services and protection from dust. Our analyses also show that cropland had increased by about 1.6 million ha from 1987 to 2010, while

  9. Recent glacial retreat in High Asia in China and its impact on water resource in Northwest China

    Institute of Scientific and Technical Information of China (English)

    YAO; Tandong; WANG; Youqing; LIU; Shiying; PU; Jianchen; S

    2004-01-01

    Under the impact of climatic warming, the glaciers in the High Asia in China have been retreating continuously with negative glacial mass balance in recent several decades. The retreat became more intensive in the past 10 years. The spatial pattern of the glacial retreat in the High Asia in China is that the smallest magnitude of retreat is in the inland of the Tibetan Plateau, the magnitude increases from the inland to the margin of the Tibetan Plateau, and the largest magnitude at the margin of the Tibetan Plateau. The glacial retreat in the High Asia in China has an important impact on the water resource of the arid regions in Northwest China. This study shows that the glacial retreat in the 1990s has caused an increase of 5.5% in river runoff in Northwest China. In the Tarim River basin, the increase of river runoff is higher than 5.5%.

  10. Urbanization Process Monitoring in Northwest China based on DMSP/OLS Nighttime Light Data

    Science.gov (United States)

    Wang, K.; Bai, L. Y.; Feng, J. Z.

    2017-02-01

    In recent years, the DMSP/OLS nighttime light data have been widely applied to various fields such as monitoring and evaluation of urbanization, estimation of social economy, economical environment and health effects, hazards analysis, and fisheries research. The general urbanized level in China has rapidly developed since the 1990s, and the cities in northwest China, which were important population centres of the ancient silk road, have also been developed in a high speed thanks to China’s national strategy of Western Development. Given the Xinjiang autonomous region as a core area of One Belt and One Road, it is very necessary to study the urbanization processes and changes of its urban system and the whole northwest region of China. In this paper, we extracted built-up areas of the cities in northwest China in 1992, 1997, 2002, 2007, and 2012, evaluated urban expansion and spatial pattern through appropriate indexes, and also quantitatively analyzed the urbanized level of each city. The results showed that the cities in northwest China generally presented high strong and rapid expansion, but there were some large differences among cities. Urban expansion forms alternate with exterior expansion and interior filling, in general, the cities externally expandedafter 2002 and internally filledbefore 2002, meanwhile, there were a high positive correlation between urban built-up areas and population growth in Xinjiang autonomous.

  11. Study on the glacier variation and its runoff responses in the arid region of Northwest China

    Institute of Scientific and Technical Information of China (English)

    刘潮海; 康尔泗; 刘时银; 陈建明; 刘宗香

    1999-01-01

    The glaciers in the arid region of Northwest China are viewed as an independent system, and glacier variation and mass balance fluctuation since the Little Ice Age and in the recent decades are estimated. Based on the estimation, the threshold time of glacier runoff against the backgrounds of the current and future varying climate conditions is simulated.

  12. From sea level to high elevation in 15 million years: Uplift history of the northern Tibetan Plateau margin in the Altun Shan

    NARCIS (Netherlands)

    Ritts, B.D.; Yue, Y.; Graham, S.A.; Sobel, E.R.; Abbink, O.A.; Stockli, D.

    2008-01-01

    Approximately 1300 in of Oligocene-Miocene clastic strata are exposed along the Miran River in the southeastern Tarim basin, where the adjacent Altun Shan form the topographic escarpment of the northern Tibetan Plateau. The sedimentary section is faulted against Proterozoic rocks of the Altun Shan i

  13. Progress and prospects of climate change impacts on hydrology in the arid region of northwest China.

    Science.gov (United States)

    Chen, Yaning; Li, Zhi; Fan, Yuting; Wang, Huaijun; Deng, Haijun

    2015-05-01

    The arid region of Northwest China, located in the central Asia, responds sensitively to global climate change. Based on the newest research results, this paper analyzes the impacts of climate change on hydrology and the water cycle in the arid region of Northwest China. The analysis results show that: (1) In the northwest arid region, temperature and precipitation experienced "sharply" increasing in the past 50 years. The precipitation trend changed in 1987, and since then has been in a state of high volatility, during the 21st century, the increasing rate of precipitation was diminished. Temperature experienced a "sharply" increase in 1997; however, this sharp increasing trend has turned to an apparent hiatus since the 21st century. The dramatic rise in winter temperatures in the northwest arid region is an important reason for the rise in the average annual temperature, and substantial increases in extreme winter minimum temperature play an important role in the rising average winter temperature; (2) There was a significant turning point in the change of pan evaporation in the northwest arid area in 1993, i.e., in which a significant decline reversed to a significant upward trend. In the 21st century, the negative effects of global warming and increasing levels of evaporation on the ecology of the northwest arid region have been highlighted; (3) Glacier change has a significant impact on hydrology in the northwest arid area, and glacier inflection points have appeared in some rivers. The melting water supply of the Tarim River Basin possesses a large portion of water supplies (about 50%). In the future, the amount of surface water will probably remain at a high state of fluctuation. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. The Impact of Industrial Transformation on Water Use Efficiency in Northwest Region of China

    Directory of Open Access Journals (Sweden)

    Qingling Shi

    2014-12-01

    Full Text Available China has been stressing the needs of promoting regional sustainable development through industrial transformation. In the northwest region of China, which is faced with both urgent socioeconomic development and fragile ecological conditions, with water scarcity being one of the major characters, the relationship between industrial transformation and water use efficiency ought to be investigated. This paper conducted an empirical analysis of industry transformation’s impact on water use efficiency by using the Input-output analysis. First, we compiled an extended Input-output table with water use account; Second, the input-output analysis model was built based on the extended Input-output table; Then, a counterfactual experiment was performed to document the water use efficiency caused by industrial transformation; Finally, water use efficiency of different sectors in both northwest region of China as a whole and its five provinces were calculated. The results show that water use efficiency of northwest region of China is improved by optimizing industrial structure. Also, sectors with low water use efficiency but huge improvement potential were found out. Then policy implications for regional sustainable development and water resources management are provided at the end of the article.

  15. Land tenure security and land investments in Northwest China

    NARCIS (Netherlands)

    Ma Xian lei, Xianlei; Heerink, N.; Ierland, van E.C.; Berg, van den M.; Shi, X.

    2013-01-01

    Purpose - The purpose of this paper is to examine the effect of perceived land tenure security in China on farmers' decisions to invest in relatively long-term land quality improvement measures, taking into account the potential endogeneity of tenure security. Design/methodology/approach – Data from

  16. Resource integration of regional economic development in northwest China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Northwestern area is the most arid and underdeveloped area in China. Lots of researches have been done to find the approaches to alleviate poverty. But there are some problems, for example, how to invest, how to use capital,and why the utilization rate is ambiguous. Water, capital and human resources are analyzed in this paper to be compared with their Utilization rates. As a result, according to the dependences of economic growth on those resources, a new approach has been selected to organize the integration ways among these resources for economic development in northwestern China. The efficient ways to develop northwestern China are: firstly, use the wanting resources most effectively to make an efficient integration model of multiple resources. For example, enhance the utilization rate of water to raise the value of other resources. Secondly, invest more in basic factors for economic development to upgrade the competitiveness in the western China. For example, invest more in primary education and sustainable development of basic natural resources in order to have more power for sustainable development.

  17. Conservation and restoration of degraded ecosystems in arid and semi-arid areas of northwest China

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In "West Development" of China, one of the most important activities is the Natural Forest Protection Program, designed to swiftly convert the focus of management and utilization of the natural forests from a timber orientation towards forest conservation, sustainable management and environmental protection. The project covered almost all the arid and semi-arid regions in Northwest region. Accompanying this great campaign this paper studied the conservation and restoration model of degraded ecosystems in arid and semi-arid lands in Northwest China. The past practices have resulted in considerably natural forest degradation and loss through land conversion (primarily for agriculture), over-harvesting, inadequate reforestation and lack of protection. The consequences have been the loss of soil and water resources, diminished timber production capacity on a sustainable basis, and environmental losses. This paper applied Aronson's restoration model and proposed the conservation, restoration, re-allocation and preservation program for the implementation of environmental improvement and natural forest conservation.

  18. Developing microfinance models to facilitate adoption of biogas systems in rural Northwest China

    Energy Technology Data Exchange (ETDEWEB)

    Harris, Gabrielle [PlaNet Finance, Beijing (China)

    2011-07-01

    This paper discusses a successful means of increasing low-income populations' access to renewable energy technology. Actions included the tailoring of micro-credits to the needs of low-income investors in biogas, the development of systems to assure long-term and efficient use of the technology, and the integration of more comprehensive trainings which increase awareness on the system's requirements for year-long operations especially during the cold winters of Northwest China. (orig.)

  19. Sand-dust Storm,Population and Environment in Northwest China

    Institute of Scientific and Technical Information of China (English)

    Liu Shao

    2004-01-01

    Sand-dust storms are the result of the integrated influences of climate, geography, society and human factors. A theoretical framework is built to explain the coherence of population growth,agriculture change and environmental degradation.On the basis of the analysis of the causes of the sand-dust storm in terms of human factors, a discussion will be given to show that these factors are internally consistent with the theoretical framework. After that, it will look at Chinas Agenda21 and try to find relevant measures to reduce such large sand-dust storms happening in Northwest China and eventually make this area develop sustainably.

  20. The Influence of Land Surface Changes on Regional Climate in Northwest China

    Institute of Scientific and Technical Information of China (English)

    XU Xingkui; ZHANG Feng; Jason K.LEVY

    2007-01-01

    Land surface changes effect the regional climate due to the complex coupling of land-atmosphere interactions. From 1995 to 2000, a decrease in the vegetation density and an increase in ground-level thermodynamic activity has been documented by multiple data sources in Northwest China, including meteorological, reanalysis from European Centre for Medium-Range Weather Forecasts (ECMWF), National Oceanic and Atmospheric Administration's (NOAA) Advanced Very High Resolution Radiometer (AVHRR) and TIROS Operational Vertical Sounder (TOVS) satellite remote sensing data. As the ground-level thermodynamic activity increases, humid air from the surrounding regions converge toward desert (and semi-desert) regions, causing areas with high vegetation cover to become gradually more arid. Furthermore, land surface changes in Northwest China are responsible for a decrease in total cloud cover, a decline in the fraction of low and middle clouds, an increase in high cloud cover (due to thermodynamic activity) and other regional climatic adaptations. It is proposed that, beginning in 1995, these cloud cover changes contributed to a "greenhouse" effect, leading to the rapid air temperature increases and other regional climate impacts that have been observed over Northwest China.

  1. Rabies Outbreaks and Vaccination in Domestic Camels and Cattle in Northwest China.

    Science.gov (United States)

    Liu, Ye; Zhang, He-Ping; Zhang, Shou-Feng; Wang, Jin-Xiang; Zhou, Hai-Ning; Zhang, Fei; Wang, Yu-Mei; Ma, Long; Li, Nan; Hu, Rong-Liang

    2016-09-01

    In contrast to many countries where rabies has been well controlled in humans and livestock, even in wildlife, rabies is still endemic in almost regions of China. In Northwest China, rabies transmitted by stray dogs and wild foxes has caused heavy economic losses to local herdsmen, as well as causing numbers of human cases. In this study, as part of an investigation of ways to prevent rabies epidemics in livestock, we report an analysis of domestic cattle and camel rabies cases in Ningxia Hui (NHAR) and Inner Mongolia Autonomous Region (IMAR) and the immune efficacy of canine inactivated rabies vaccines in these animals. We found that rabies viruses from these animals are closely related to dog-hosted China I and fox-associated China III lineages, respectively, indicating that the infections originated from two different sources (dogs and wild foxes). As well as the previously reported Arctic and Arctic-related China IV lineage in IMAR, at least three separate phylogenetic groups of rabies virus consistently exist and spread throughout Northwest China. Since there is no licensed oral vaccine for wild foxes and no inactivated vaccine for large livestock, local canine inactivated vaccine products were used for emergency immunization of beef and milk cattle and bactrian (two-humped) camels in local farms. Compared with a single injection with one (low-efficacy) or three doses (high-cost), a single injection of a double dose of canine vaccine provided low-price and convenience for local veterinarians while inducing levels of virus neutralizing antibodies indicative of protection against rabies for at least 1 year in the cattle and camels. However, licensed vaccines for wildlife and large domestic animals are still needed in China.

  2. Genetic variation in yield and chemical composition of wide range of sorghum accessions grown in north-west China

    NARCIS (Netherlands)

    Wang, J.S.; Wang, M.L.; Spiertz, J.H.J.; Liu, Z.; Han, L.; Xie, G.H.

    2013-01-01

    Sorghum can be grown on marginal and waste lands as a versatile feedstock for biofuel production in the vast areas of north-west China. Fifty-six sorghum accessions were grown in 2009 at the experimental station of Xinjiang Agricultural University, located at Urumchi, Xinjiang, China. A total of 31

  3. Relationship Between Agriculture and Ecological Deterioration, Restoration and Reconstruction in Loess Plateau Areas of Northwest China

    Institute of Scientific and Technical Information of China (English)

    CHENG Xu

    2002-01-01

    A comprehensive analysis was conducted on the current situation as well as historic succession process of agriculture and ecological conditions in Northwest China, in particular in the Loess Plateau, by means of a inter-disciplinary approach of ecology, agro-geohistory, and agronomy. It was concluded that the fundamental causes responsible for the ecological deterioration, signed by the poor agro-productivity and serious soil erosion, had been the extensive cropping system by ever-increasing reclamation on semi-drought slope land, where initiated a natural vegetation of brushy grasses with sparse trees, thus suitable only for animal husbandry. Based on an identification of specific actual status of China, several countermeasures of correctly dealing with the relationship between agricultural development and the ecological restoration and reconstruction were proposed, including to get breakthrough first in the transection area by means of the rational use of resources and the raising of agro-system productivity, to promoting "water conservancy-type ecological agriculture" through the radical shift of traditional production pattern, and the adoption of a policy of proper degree of grain self-reliance, as well as to construct livestock industry base in Northwest China.

  4. Hydrologic modeling of the Heihe watershed by DLBRM in Northwest China

    Institute of Scientific and Technical Information of China (English)

    Carlo; Demarchi; Thomas; E.Croley; Ⅱ; Tim; Hunter

    2009-01-01

    Water shortage is a chronic problem in arid Northwest China.The rapid population growth and expanding urbanization as well as potential climate change impacts are likely to worsen the situation,threatening domestic,irrigation,and industrial supplies and even the survival of the ecosystems in Northwest China.This paper describes the preliminary work of adapting the Distributed Large Basin Runoff Model(DLBRM) to the Heihe watershed(the second largest inland river in arid Northwestern China,with a drainage area of 128,000 km2) for understanding distribution of glacial-snow melt,groundwater,surface runoff,and evapotranspi-ration,and for assessing hydrological impacts of climate change and glacial recession on water supply in the middle and lower reaches of the watershed.Preliminary simulation results show that the Qilian Mountain in the upper reach area produces most runoff in the Heihe watershed.The simulated daily river flows during the period of 1990-2000 indicate that the Heihe River dis-charges about 1×109 m3 of water from the middle reach(at Zhengyixia Station) to lower reach,with surface runoff and interflow contributing 51 and 49 percent respectively.The sandy lower soil zone in the middle reach has the highest evapotranspiration rate and also contributes nearly half of the river flow.Work underway focuses on the DLBRM model improvement and incorporation of the climate change and management scenarios to the hydrological simulations in the watershed.

  5. Hydrologic modeling of the Heihe watershed by DLBRM in Northwest China

    Institute of Scientific and Technical Information of China (English)

    ChanSheng He; Carlo Demarchi; Thomas E. Croley Ⅱ; Qi Feng; Tim Hunter

    2009-01-01

    Water shortage is a chronic problem in arid Northwest China. The rapid population growth and expanding urbanization as well as potential climate change impacts are likely to worsen the situation, threatening domestic, irrigation, and industrial supplies and even the survival of the ecosystems in Northwest China. This paper describes the preliminary work of adapting the Distributed Large Basin Runoff Model (DLBRM) to the Heihe watershed (the second largest inland river in arid Northwestern China, with a drainage area of 128,000 km2) for understanding distribution of glacial-snow melt, groundwater, surface runoff, and evapotranspiration, and for assessing hydrological impacts of climate change and glacial recession on water supply in the middle and lower reaches of the watershed. Preliminary simulation results show that the Qilian Mountain in the upper reach area produces most runoff in the Heihe watershed. The simulated daily river flows during the period of 1990-2000 indicate that the Heihe River discharges about 1×109 m3 of water from the middle reach (at Zhengyixia Station) to lower reach, with surface runoff and interflow contributing 51 and 49 percent respectively. The sandy lower soil zone in the middle reach has the highest evapotranspiration rate and also contributes nearly half of the river flow. Work underway focuses on the DLBRM model improvement and incorporation of the climate change and management scenarios to the hydrological simulations in the watershed.

  6. Seroprevalence of Toxoplasma gondii infection in household and stray cats in Lanzhou, northwest China

    Directory of Open Access Journals (Sweden)

    Wu Song-Ming

    2011-11-01

    Full Text Available Abstract Background Toxoplasma gondii is an important protozoan parasite infecting humans and almost all warm-blooded animals. As the only definitive host, cats play a crucial role in the transmission of T. gondii infection by shedding parasite oocysts in their feces. However, little information on T. gondii infection in cats was available in Lanzhou, northwest China. This study was performed to determine the seroprevalence of T. gondii infection in household and stray cats in Lanzhou, northwest China. Results A total of 221 (179 households and 42 strays blood samples were collected from clinically healthy cats admitted to several pet hospitals located in Lanzhou City, between November 2010 and July 2011 for the serological detection of T. gondii infection. The majority (207 of these cats represented Chinese Lihua cats. 47 of 221 (21.3% examined cats were seropositive for T. gondii infection using the modified agglutination test (MAT at the cut-off of 1:25. The seroprevalence in household and stray cats was assessed to be 15.6% and 45.2%, respectively, and the difference was statistically significant (P 0.05. The seroprevalence ranged from 15.1% to 25.8% among different age groups, but the differences were not statistically significant (P >0.05. Studies showed that there was no relationship between seroprevalence and the gender (P >0.05. Conclusions The present survey indicated the high seroprevalence of T. gondii in cats in Lanzhou, northwest China, which poses a threat to animal and human health. Therefore, measures should be taken to control and prevent toxoplasmosis of cats in this area.

  7. Impact of Climate Change on Vegetation Growth in Arid Northwest of China from 1982 to 2011

    Directory of Open Access Journals (Sweden)

    Rong Zhang

    2016-04-01

    Full Text Available Previous studies have concluded that the increase in vegetation in the arid northwest of China is related to precipitation rather than temperature. However, these studies neglected the effects of climate warming on water availability that arise through changes in the melting characteristics of this snowy and glaciated region. Here, we characterized vegetation changes using the newly improved third-generation Global Inventory Modeling and Mapping Studies Normalized Difference Vegetation Index (GIMMS-3g NDVI from 1982 to 2011. We analyzed the temperature and precipitation trends based on data from 51 meteorological stations across Northwest China and investigated changes in the glaciers using Gravity Recovery and Climate Experiment (GRACE data. Our results indicated an increasing trend in vegetation greenness in Northwest China, and this increasing trend was mostly associated with increasing winter precipitation and summer temperature. We found that the mean annual temperature increased at a rate of 0.04 °C per year over the past 30 years, which induced rapid glacial melting. The total water storage measured by GRACE decreased by up to 8 mm yr−1 and primarily corresponded to the disappearance of glaciers. Considering the absence of any observed increase in precipitation in the growing season, the vegetation growth may have benefited from the melting of glaciers in high-elevation mountains (i.e., the Tianshan Mountains. Multiple regression analysis showed that temperature was positively correlated with NDVI and that gravity was negatively correlated with NDVI; together, these variables explained 84% of the NDVI variation. Our findings suggest that both winter precipitation and warming-induced glacial melting increased water availability to the arid vegetation in this region, resulting in enhanced greenness.

  8. Prevalence and determinants of metabolic syndrome among adults in a rural area of Northwest China.

    Directory of Open Access Journals (Sweden)

    Yaling Zhao

    Full Text Available To evaluate the prevalence and determinants of metabolic syndrome (MetS among adults in a rural area of Northwest China.A population-based cross-sectional study was conducted in 2010 among adults aged 18 to 80 years in rural areas of Hanzhong, in Northwest China. Interview, physical and clinical examinations, and fasting blood glucose and lipid measurements were completed for 2990 adults. The definitions of MetS proposed by the Third Report of the National Cholesterol Education Program Expert Panel (Adults Treatment Panel III, ATP III and the International Diabetes Federation (IDF, and the modified ATP III definition for Asian population were used and compared. Proportions were adjusted for age and sex.The prevalence of MetS was 7.9%, 10.8% and 15.1% according to ATP III, IDF and modified ATP III criteria, respectively. Agreement between ATP III and IDF criteria and that between ATP III and modified ATP III criteria were moderate (Kappa = 0.52 and 0.64, respectively, whereas agreement between IDF and modified ATP III criteria was good (Kappa = 0.83. The prevalence of MetS increased with age, and was higher in women than in men (10.4% versus 5.4%, 13.6% versus 8.1% and 17.4% versus 12.8%, according to ATP III, IDF and modified ATP III criteria, respectively. The most common MetS component was high blood pressure. Having family history of hypertension, lack of physical activity, high economical level, overweight and obesity were positively associated with MetS.MetS is prevalent among rural adults in Northwest China and high blood pressure is the most common MetS component. Prevention and treatment of hypertension and MetS should be a public health priority to reduce cardiovascular diseases in rural areas of Northwest China. More attention should be given to the elderly, women, people with family history of hypertension and obese people who are at high risk of MetS.

  9. The Association of Maternal Lifestyle with Birth Defects in Shaanxi Province, Northwest China.

    Directory of Open Access Journals (Sweden)

    Leilei Pei

    Full Text Available The main objective was to investigate the burden of birth defects among alive infants and explore the impact of maternal lifestyle during pregnancy on the burden of birth defects in Northwest China.A stratified multi-stage sampling method was used to study infants born during 2010-2013 (and their mothers in Shaanxi province of Northwest China. Socio-demographic information was collected using a structured questionnaire, and medical records from the local hospitals were used to determine the final diagnosis of birth defects. Poisson regression analysis was performed to assess the association between maternal lifestyles during pregnancy and the burden of birth defects, while adjusting for potential confounders.We sampled 29098 infants, of whom 629 (i.e. 216.17 per 10000 were observed to have congenital defects. Cardiovascular system defects (77.32 per 10000 were found to be the most common. Mothers who had ever consumed alcohol during pregnancy were found to have infants with a higher prevalence of some categories of birth defects, including nervous system (Prevalence Rate Ratio, PRR:14.67, 95% CI: 1.94, 110.92, cardiovascular system (PRR:3.22, 95% CI: 1.02, 10.16 and oral clefts (PRR:9.02, 95% CI: 2.08, 39.10 in contrast to infants of mothers without any alcohol consumption. Maternal passive smoking during pregnancy lead to the increased burden of malformations of eye, ear, face and neck (PRR:1.95, 95% CI: 1.15, 3.33, cardiovascular system (PRR:1.70, 95% CI: 1.25, 2.31 and respiratory system (PRR:9.94, 95% CI: 2.37, 41.76 in their newborns. Further, tea or coffee consumption during pregnancy was positively correlated with the burden of specific birth defects, such as cardiovascular system (PRR: 2.44, 95% CI: 1.33, 4.46 and genital organs (PRR:14.72, 95% CI: 1.87, 116.11 among infants.The prevalence of birth defects was high in Shaanxi province of Northwest China. The unhealthy lifestyles of mothers during pregnancy may increase the prevalence of

  10. Observation of Directional Ocean Wave Spectra in China Seas and Northwest Pacific Ocean Using SAR Retrieval Software

    Science.gov (United States)

    Liu, Xiaoyan; Zeng, Kan; He, Mingxia

    2014-11-01

    A software to retrieve directional ocean wave spectra from SAR images has been developed for China seas and northwest Pacific. The software, written with C programming language, is based on the MPI method proposed by Hasselmann. It is designed to support the wave mode SAR data of ERS, Envisat, Sentinel and so on. The directional ocean wave spectra produced by this software are validated with buoy data in global ocean area, northwest Pacific and China seas and the retrieved significant wave height (SWH) errors are 5.2%, 4.9% and 9.3% respectively. About 15,000 directional ocean wave spectra are obtained with the software from the wave mode data of Envisat/ASAR over the China seas and northwest Pacific during the period between Jan 2003 and Jan 2012. The preliminary analysis is presented.

  11. Winter coastal upwelling off northwest Borneo in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    YAN Yunwei; LING Zheng; CHEN Changlin

    2015-01-01

    Winter coastal upwelling off northwest Borneo in the South China Sea (SCS) is investigated by using satellite data, climatological temperature and salinity fields and reanalysis data. The upwelling forms in Decem-ber, matures in January, starts to decay in February and almost disappears in March. Both Ekman trans-port induced by the alongshore winter monsoon and Ekman pumping due to orographic wind stress curl are favorable for the upwelling. Transport estimates demonstrate that the month-to-month variability of Ekman transport and Ekman pumping are both consistent with that of winter coastal upwelling, but Ek-man transport is two times larger than Ekman pumping in January and February. Under the influence of El Niño-Southern Oscillation (ENSO), the upwelling shows remarkable interannual variability: during winter of El Niño (La Niña) years, an anticyclonic (a cyclonic) wind anomaly is established in the SCS, which behaves a northeasterly (southwesterly) anomaly and a positive (negative) wind stress curl anomaly off the north-west Borneo coast, enhancing (reducing) the upwelling and causing anomalous surface cooling (warming) and higher (lower) chlorophyll concentration. The sea surface temperature anomaly (SSTA) associated with ENSO off the northwest Borneo coast has an opposite phase to that off southeast Vietnam, resulting in a SSTA seesaw pattern in the southern SCS in winter.

  12. Natural hazards along the oil and gas transport pipelines in Northwest China

    Science.gov (United States)

    Hong, Xie; Yu, Zhao; Yong, Li

    2017-04-01

    The northwest China, including the provincial districts of Xinjiang, Qinghai, and Gansu, is the key area for transporting oil and gas from the west to the east, through where runs the China-Kazakhstan crude oil pipeline linking the Central Asia resources of oil and gas. The area is 283.6 km2and the pipeline is 15 650 km long, suffering severe disasters destroying the operation of oil and gas transport. Major disasters are torrential floods, debris flows, rockfalls, landslides, wind erosion, and ground subsidence, having the following characteristics: 1) most disasters are distributed along the rivers; 2) special strata are effective in controlling some types of disasters; 3) landslides, collapses and debris flows are especially concentrated in steep landforms; 4) the disasters are highly likely to occur under the extreme climate; 5) the disasters are distributed in parallel to the earthquake zones.

  13. Review and proposals on vegetation restoration in the Loess Plateau, Northwest China

    Institute of Scientific and Technical Information of China (English)

    Wenhui ZHANG; Guobin LIU

    2008-01-01

    A group of scientists conducted a comprehen-sive investigation on ecological safety and water and soil erosion in the Northwest Loess Plateau, Northwest China. The data gathered was analyzed in terms of achievement, existing problems, and strategy and mea-sures on vegetation restoration in the area. Since the policies of conversion from cropland to forest (CCF) and forbid grazing and cutting (FGC) were carried out, vegetation quality and coverage rate increased quickly in the Loess Plateau area, strengthening the concept of eco-environment protection. Environment harness measure-ments were optimized. The multiform investments on eco-environment and urbanization development in China will benefit vegetation restoration. However, there have been some persisting problems, such as the shortage of investment, instability of government policy, expectation of extravagant economic benefit, larger rate of planta-tion, and scarce technologies supporting vegetation restoration. Many key theories and practice problems require an urgent resolution. In the future, short-, mid-,and long-term goals for vegetation restoration should be clear, achievement should be expanded, and the natural restoration area should be increased. The benefit for the contractor on vegetation restoration should be ensured. Investment on vegetation building research work should be increased.

  14. Planning for Regional Water Resources in Northwest China Using a Dynamic Simulation Model

    Science.gov (United States)

    Chen, C.; Kalra, A.; Ahmad, S.

    2014-12-01

    Problem of water scarcity is prominent in northwest China due to its typical desert climate. Exceedence of sustainable yield of groundwater resources has resulted in groundwater depletion, which has raised a series of issues such as drying wells, increasing pumping costs and environmental damage. With a rapid agricultural and economic development, population increase has added extra stress on available water resources by increasing municipal, agricultural and industrial demands. This necessitates efficient water resources management strategies with better understanding of the causes of water stress and options for sustainable development of economy and management of environment. This study focuses on simulating the water supply and demand, under the influence of changing climate, for Shanshan County, located in northwest of China. A dynamic simulation model is developed using the modeling tool Stella for monthly water balance for the period ranging from 2000-2030. Different future water demand and supply scenarios are developed to represent: (1) base scenario- with current practices; (2) change of the primary water source; (3) improvement of irrigation efficiency; (4) reduction of irrigation area; and (5) reduction of industrial water demand. The results indicate that besides growing demand, the low water use efficiency and low level of water reuse are the primary concerns for water scarcity. Groundwater recharge and abstraction could be balanced by 2030, by reducing industrial demand by 50% and using high efficiency irrigation for agriculture. The model provided a better understanding of the effect of different policies and can help in identifying water resources management strategies.

  15. Aeolian particle transport inferred using a ~150-year sediment record from Sayram Lake, arid northwest China

    Directory of Open Access Journals (Sweden)

    Long Ma

    2015-05-01

    Full Text Available We studied sediment cores from Sayram Lake in the Tianshan Mountains of northwest China to evaluate variations in aeolian transport processes over the past ~150 years. Using an end-member modeling algorithm of particle size data, we interpreted end members with a strong bimodal distribution as having been transported by aeolian processes, whereas other end members were interpreted to have been transported by fluvial processes. The aeolian fraction accounted for an average of 27% of the terrigenous components in the core. We used the ratio of aeolian to fluvial content in the Sayram Lake sediments as an index of past intensity of aeolian transport in the Tianshan Mountains. During the interval 1910-1930, the index was high, reflecting the fact that dry climate provided optimal conditions for aeolian dust transport. From 1930-1980, the intensity of aeolian transport was weak. From the 1980s to the 2000s, aeolian transport to Sayram Lake increased. Although climate in northwest China became more humid in the mid-1980s, human activity had by that time altered the impact of climate on the landscape, leading to enhanced surface erosion, which provided more transportable material for dust storms. Comparison of the Lake Sayram sediment record with sediment records from other lakes in the region indicates synchronous intervals of enhanced aeolian transport from 1910 to 1930 and 1980 to 2000.

  16. Impact of Global Warming on Water Resource in Arid Area of Northwest China

    Institute of Scientific and Technical Information of China (English)

    LU Aigang; DING Yongjian; PANG Hongxi; YUAN Lingling; HE Yuanqing

    2005-01-01

    As the unprecedented global warming is under way, the glacier retreat is getting more and more serious. In the inland arid area of Northwest China, due to very scarce precipitation, where there is water, there are oases. And the glacier melt water amounts to 22 % of the total direct supply of the inland river water and is of crucial importance to the survival and development of the oases. In this paper,using both the observed data and the previous research achievements of the glaciers in the inland valley of Northwest China where the oasis depending on the glacier is the only location suitable for human living, the authors describe the glacier retreat trend over the past half century, focusing on discussing the possible impact of the glacier retreat on the melt water runoff that is almost the only water resource efficient to nourish the oases. The authors find that even with increasing amount of water from the glacier with global warming, the water shortage is getting more and more serious and the environment is under a degrading way due to the accelerating economical development. The water shortage is bound to be more serious if the glacier retreat keeps on, especially after the glacier melt water is over its top for the degraded glacier scale. So suggestions are stressed in the end that a new water-saving pattern should be adopted in the area for a sustainable development due to the warming-up induced continuous glacier retreat.

  17. Analysis of the severe group dust storms in eastern part of Northwest China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Based on the available original dust storm records from 60 meteorological stations, we discussed the identification standard of severe dust storms at a single station and constructed a quite complete time series of severe group dust storms in the eastern part of Northwest China in 1954-2001.The result shows that there were 99 severe group dust storms in this region in recent 48 years. The spatial distribution indicates that the Alax Plateau, most parts of the Ordos Plateau and most parts of the Hexi Corridor are the main areas influenced by severe group dust storms. In addition, the seasonand the month with the most frequent severe group dust storms are spring and April, accounting for 78.8% and 41.4% of the total events respectively. During the past 48 years the lowest rate of severe group dust storms occurred in the 1990s. Compared with the other 4 decades, on the average, the duration and the affected area of severe group dust storms are relatively short and small during the 1990s. In 2000 and 2001, there were separately 4 severe group dust storms as the higher value after 1983 in the eastern part of Northwest China.

  18. REPORT OF HLA DISTRIBUTION IN 2315 VOLUNTEER DONORS OF CHINESE BONE MARROW BANK FROM NORTHWEST CHINA

    Institute of Scientific and Technical Information of China (English)

    Jin Tianbo; Gao Ya; Zhang Hongbo; Zhao Junhai; Lai Jianghua; Lai Shuping; Li Shengbin

    2005-01-01

    Objective To report the HLA data of volunteer donors of Chinese bank from Northwest China and characterize the distribution of HLA genes in Northwest China. Methods HLA-A, B antigens of 2315 volunteer donors were examined by the method of microlymphocytetoxicity (MLT) test .The antigen frequencies(AF) were assessed by directly counting; and based on that gene frequencies(GF) were calculated. HLA data from other population were collected and distribution characteristics were compared. With the raw data, Hardy-Weinberg equilibrium, statistical parameters of forensic medicine interest for HLA were computed. Results A total of 18 specific antigens were detected in HLA-A and the most frequent antigen was A2 . AF and GF were 0.5136 and 0.3026, respectively. A total of 42 specific antigens were detected in HLA-B and the most frequent antigen was A13. Its AF and GF were 0.1978 and 0.1044, respectively. The heterozygosity(H), polymorphism information content(PIC), discrimination power(DP) and probability of paternity exclusion (PPE) of HLA-A were 0.8215, 0.8212, 0.9356 and 0.7798 accordingly; while H,PIC, DP and PPE of HLA-B were 0.9322, 0.9322, 0.9878 and 0.9528. Conclusion The polymorphism of HLA-A,B genes is characteristic in Chinese. In this research, the genetic trait of HLA in 2315 volunteers is consistent with Northern Han population.

  19. Modeled effects of irrigation on surface climate in the Heihe River Basin, Northwest China

    Science.gov (United States)

    Zhang, Xuezhen; Xiong, Zhe; Tang, Qiuhong

    2017-08-01

    In Northwest China, water originates from the mountain area and is largely used for irrigation agriculture in the middle reaches. This study investigates the local and remote impact of irrigation on regional climate in the Heihe River Basin, the second largest inland river basin in Northwest China. An irrigation scheme was developed and incorporated into the Weather Research and Forecasting (WRF) model with the Noah-MP land surface scheme (WRF/Noah-MP). The effects of irrigation is assessed by comparing the model simulations with and without consideration of irrigation (hereafter, IRRG and NATU simulations, respectively) for five growth seasons (May to September) from 2009 to 2013. As consequences of irrigation, daily mean temperature decreased by 1.7°C and humidity increased by 2.3 g kg-1 (corresponding to 38.5%) over irrigated area. The temperature and humidity of IRRG simulation matched well with the observations, whereas NATU simulation overestimated temperature and underestimated humidity over irrigated area. The effects on temperature and humidity are generally small outside the irrigated area. The cooling and wetting effects have opposing impacts on convective precipitation, resulting in a negligible change in localized precipitation over irrigated area. However, irrigation may induce water vapor convergence and enhance precipitation remotely in the southeastern portion of the Heihe River Basin.

  20. Ecosystem Evapotranspiration as a Response to Climate and Vegetation Coverage Changes in Northwest Yunnan, China.

    Directory of Open Access Journals (Sweden)

    Hao Yang

    Full Text Available Climate and human-driven changes play an important role in regional droughts. Northwest Yunnan Province is a key region for biodiversity conservation in China, and it has experienced severe droughts since the beginning of this century; however, the extent of the contributions from climate and human-driven changes remains unclear. We calculated the ecosystem evapotranspiration (ET and water yield (WY of northwest Yunnan Province, China from 2001 to 2013 using meteorological and remote sensing observation data and a Surface Energy Balance System (SEBS model. Multivariate regression analyses were used to differentiate the contribution of climate and vegetation coverage to ET. The results showed that the annual average vegetation coverage significantly increased over time with a mean of 0.69 in spite of the precipitation fluctuation. Afforestation/reforestation and other management efforts attributed to vegetation coverage increase in NW Yunnan. Both ET and WY considerably fluctuated with the climate factors, which ranged from 623.29 mm to 893.8 mm and -51.88 mm to 384.40 mm over the time period. Spatially, ET in the southeast of NW Yunnan (mainly in Lijiang increased significantly, which was in line with the spatial trend of vegetation coverage. Multivariate linear regression analysis indicated that climatic factors accounted for 85.18% of the ET variation, while vegetation coverage explained 14.82%. On the other hand, precipitation accounted for 67.5% of the WY. We conclude that the continuous droughts in northwest Yunnan were primarily climatically driven; however, man-made land cover and vegetation changes also increased the vulnerability of local populations to drought. Because of the high proportion of the water yield consumed for subsistence and poor infrastructure for water management, local populations have been highly vulnerable to climate drought conditions. We suggest that conservation of native vegetation and development of water

  1. Soya and isoflavone intakes associated with reduced risk of oesophageal cancer in north-west China.

    Science.gov (United States)

    Tang, Li; Lee, Andy H; Xu, Fenglian; Zhang, Taotao; Lei, Jun; Binns, Colin W

    2015-01-01

    To ascertain the association between soya consumption, isoflavone intakes and oesophageal cancer risk in remote north-west China, where the incidence of oesophageal cancer is known to be high. Case-control study. Information on habitual consumption of soya foods and soya milk was obtained by personal interview. The intakes of isoflavones were then estimated using the US Department of Agriculture nutrient database. Logistic regression analyses were performed to assess the association between soya consumption, isoflavone intakes and oesophageal cancer risk. Urumqi and Shihezi, Xinjiang Uyghur Autonomous Region, China. Participants were 359 incident oesophageal cancer patients and 380 hospital-based controls. The oesophageal cancer patients consumed significantly less (P soya foods (mean 57·2 (sd 119·0) g/d) and soya milk (mean 18·8 (sd 51·7) ml/d) than the controls (mean 93·3 (sd 121·5) g/d and mean 35·7 (sd 73·0) ml/d). Logistic regression analyses showed an inverse association between intake of soya products and the risk of oesophageal cancer. The adjusted odds were OR = 0·33 (95 % CI 0·22, 0·49) and OR = 0·48 (95 % CI 0·31, 0·74) for consuming at least 97 g of soya foods and 60 ml of soya milk daily (the highest tertiles of consumption), respectively, relative to the lowest tertiles of consumption. Similarly, inverse associations with apparent dose-response relationships were found between isoflavone intakes and oesophageal cancer risk. Habitual consumption of soya products appears to be associated with reduced risk of oesophageal cancer in north-west China.

  2. Year aridity index patterns in northwest China and the relationship to summer North Atlantic sea surface temperature

    Institute of Scientific and Technical Information of China (English)

    YAN Yan; ZHAO Xinyi; ZHOU Liping

    2008-01-01

    Aim to linking the variability of drought in northwest China to the oceanic influence of North Atlantic SSTs at the background of global warming and at the regional climate change shifting stages, year aridity index variations in northwest China and summer North Atlantic sea surface temperature (SST) variations are examined for the 44 a period of 1961--2004 using singular value de-composition (SVD) analysis. Results show that the SST anomalies (SSTA) in the North Atlantic in summer reflected three basic models. The first SVD mode of SST pattern shows a dipole - like variation with the positive center located at southwest and nega-tive center at northeast of extratropical North Atlantic. And it strongly relates to the positive trend in AI variation in northwest China. The second coupled modes display the coherent positive anomalies in extratropical North Atlantic SST and the marked opposite trend of AI variability between north and south of Xinjiang. In addition, the lag correlation analysis of the first mode of SSTA and geopotential heights at 500 hPa variations also shows that the indication of the former influencing the latter configuration, which re-sult in higher air temperature and less precipitation when the SSTA in the North Atlantic Ocean in summer motivated Eurasian cir-culation of EA pattern, further to influence the wet - dry variations in northwest China by the ocean-to - atmosphere forcing.

  3. A population-based study examining hepatitis B virus infection and immunization rates in Northwest China.

    Directory of Open Access Journals (Sweden)

    Zhaohua Ji

    Full Text Available BACKGROUND AND AIM: Current baseline data regarding the prevalence of hepatitis B virus (HBV infections and the immune status in hyperendemic areas is necessary in evaluating the effectiveness of ongoing HBV prevention and control programs in northwest China. This study aims to determine the prevalence of chronic HBV infections, past exposure rates, and immune response profiles in Wuwei City, northwest China in 2010. METHODS: Cross-sectional household survey representative of the Wuwei City population. 28,579 participants were interviewed in the seroepidemiological survey ≥1 year of age. House to house screening was conducted using a standard questionnaire. All serum samples were screened by enzyme-linked immunoassays for the presence of hepatitis B surface antigen, antibodies against HBV surface antigen, and antibodies to the hepatitis B core antigen. RESULTS: Among individuals ≥1 year of age, 7.2% (95%CI: 6.3-8.1% had chronic HBV infections, 43.9% (CI: 40.4-47.4% had been exposed to HBV, and 23.49% (CI: 21.6-25.3% had vaccine-induced immunity. Multi-factor weighted logistic regression analysis showed that having household contact with HBV carriers (OR = 2.6, 95%CI: 2.3-3.0 and beauty treatments in public places (OR = 1.2, 95%CI: 1.1-1.3 were the risk factors of HBV infection in whole population. Having household contact with HBV carriers (OR = 3.8, 95% CI: 2.2-6.5 and lack of hepatitis vaccination (OR = 2.0, 95% CI: 1.4-3.3 were the risk factors for HBV infection in children aged 1-14 years. CONCLUSIONS: Hepatitis B infection remains a serious public health problem in northwest China. Having household contact with HBV carriers and beauty treatments in public places represented HBV infection risk factors. Hepatitis B vaccine immunization strategies need further improvement, particularly by targeting the immunization of rural migrant workers.

  4. Quantitative Analysis and Comparison of BMI among Han, Tibetan, and Uygur University Students in Northwest China

    Directory of Open Access Journals (Sweden)

    Bai Jingya

    2013-01-01

    Full Text Available Objectives. To fully analyze and compare BMI among Han, Tibetan, and Uygur university students, to discuss the differences in their physical properties and physical health, and thus to provide some theoretical suggestions for the improvement of students’ physical health. Methods. The cross-sectional random cluster sampling was used to investigate 10103 Han, Tibetan, and Uygur university students, aged 20–24 in Northwest China, and their height and weight were measured to calculate BMI. The BMI classification criteria for Chinese established by Work Group on Obesity in China (WGOC were used for screening. Results. Han, Tibetan, and Uygur university students show low obesity rates but high overweight rates. Han, Tibetan, and Uygur university students present a high rate of underweight, normal weight, and overweight, respectively. Female Han students show higher underweight and normal weight rates, but lower overweight and obesity rates, than male Han students. Female Tibetan students show higher normal weight rate, but lower overweight and obesity rates, than male Tibetan students. BMI increases with age for male students but decreases with age for female students. Male Uygur students show higher obesity rate than female Uygur students. Tibetan and Uygur university students have higher BMI than other minorities in South China.

  5. Molecular detection and characterization of Anaplasma spp. in sheep and cattle from Xinjiang, northwest China.

    Science.gov (United States)

    Yang, Jifei; Li, Youquan; Liu, Zhijie; Liu, Junlong; Niu, Qingli; Ren, Qiaoyun; Chen, Ze; Guan, Guiquan; Luo, Jianxun; Yin, Hong

    2015-02-19

    Anaplasmosis is caused by obligate intracellular bacteria in the genus Anaplasma. These bacterial pathogens are transmitted by ticks and impact both human and animal health. This study was conducted to determine the prevalence and molecular characterization of Anaplasma spp. in ruminants sampled in Xinjiang, northwest China. A survey was performed in August 2012 in rural areas of six counties in Xinjiang province. A total of 250 blood samples from ruminants were collected and tested for the presence of Anaplasma spp. by PCR. Positive samples were genetically characterized based on the 16S rRNA and msp4 genes. The results showed a high prevalence of Anaplasma spp. in ruminants, with at least three different Anaplasma species detected (A. phagocytophilum, A. bovis and A. ovis). The mean prevalence of single infection with each species was 17.6% (A. phagocytophilum), 4.8% (A. bovis) and 40.5% (A. ovis). Coinfection occurred in 20 (8.0%) animals. Phylogenetic analysis of the 16S rRNA gene of A. bovis and A. phagocytophilum revealed a higher degree of genetic diversity for the latter. The results for A. ovis showed genotypic variation among geographic regions in China. In addition, a closely related isolate to the canine pathogen A. platys was identified in ruminants. This survey revealed a high prevalence of Anaplasma sp. infections in sheep and cattle in the northwestern border regions of China, indicating the potential risk of transboundary disease.

  6. Groundwater circulation and hydrogeochemical evolution in Nomhon of Qaidam Basin, northwest China

    Indian Academy of Sciences (India)

    Yong Xiao; Jingli Shao; Yali Cui; Ge Zhang; Qiulan Zhang

    2017-03-01

    In this study, analysis of hydrogeological conditions, as well as hydrochemistry and isotopic tools were used to get an insight into the processes controlling mineralization, recharge conditions, and flow pattern of groundwater in a typical arid alluvial-lacustrine plain in Qaidam Basin, northwest China. Analysisof the dissolved constituents reveals that groundwater evolves from fresh water (TDS=300–1000 mg/l) to saline water (TDS ≥5000 mg/l) along the flow paths, with the water type transiting from HCO ₃•Cl– Na•Mg to HCO ₃•Cl–Na, and eventually to Cl–Na. Groundwater chemical evolution is mainly controlled by water–rock interaction and the evaporation–crystallization process. Deuterium and oxygen-18 isotopes in groundwater samples indicate that the recharge of groundwater is happened by meteoric water andglacier melt-water in the Kunlun Mountains, and in three different recharge conditions. Groundwater ages, estimated by the radiogenic (³H and ¹⁴C) isotope data, range from present to Holocene (~28ka). Based on groundwater residence time, hydrogeochemical characteristics, field investigation, and geological structure distribution, a conceptual groundwater flow pattern affected by uplift structure is proposed, indicating that shallow phreatic water is blocked by the uplift structure and the flow directionis turned to the northwest, while high pressure artesian water is formed in the confined aquifers at the axis of the uplift structure.

  7. Trends and corresponding policies related to population, resources, environment and economic development in northwest China.

    Science.gov (United States)

    Zhang, Z; Zhu, L

    1994-01-01

    A model is presented of the interaction between population, resources, environment, and the economic system in the northwest region of China. Population pressure is yielding important impacts on the environment. Development should be guided by effective population control and continuous agricultural development. Alternative strategies include: 1) Identify effective ways to curb population growth, e.g., investment in social and economic development, and formation of a social environment with social security assurances conducive to population control. Public campaigns need to address the links between poverty and population, to awaken people's sense of responsibility, and to change people's desire for more children. 2) Give education a priority as a means of upgrading the quality of rural labor. Mass media must popularize elementary school education and nine years of education. 3) Encourage migration out of the northwest. 4) Use technology to protect and correct land resources. Local regulations are needed on land management to guarantee proper planning, use, protection, and conservation of land. 5) Upgrade agricultural structures, develop forestry and grasslands, protect water and soil, and improve the ecological conditions. 6) Invest capital in such farm constructions as irrigation systems. 7) Increase investments in agriculture in order to assure productivity and reserves and to speed the transition to modern agricultural practices. 8) Raise land efficiency by increasing imports of grain and cereals from outside the region. 9) Develop township enterprises and the rural economy.

  8. Agricultural reclamation policy and environmental changes In the northwest China during the Qing dynasty

    Institute of Scientific and Technical Information of China (English)

    Zhao Zhen

    2006-01-01

    Northwest China,including the provinces of Shaanxi,Gansu,Ningxia,and a small part of the Inner Mongolian Autonomous Region,was not only one of the earliest developed areas in history,but also one of the most ecologically fragile belts.The traditionally sustainable land reclamation and cultivation policies for the development of an agricultural economy adopted and implemented in administrations during different periods of the Qing dynasty,greatly raised farming and stock production.However,this led to imbalances in the originaUy fragile ecological environment.The negative effects such as rapidly expanding desertification,worsening water and soil erosions,increased cost of production,enlarged investment,vicious cycles and failing economy can serve as a lesson for contemporary development.

  9. Optical properties and source analysis of aerosols over a desert area in Dunhuang, Northwest china

    Science.gov (United States)

    Ma, Yongjing; Xin, Jinyuan; Ma, Yining; Kong, Lingbin; Zhang, Kequan; Zhang, Wenyu; Wang, Yuesi; Wang, Xiuqin; Zhu, Yongfeng

    2017-08-01

    Aerosol observational data for 2012 obtained from Dunhuang Station of CARE-China (Campaign on Atmospheric Aerosol Research Network of China) were analyzed to achieve in-depth knowledge of aerosol optical properties over Dunhuang region. The results showed that the annual average aerosol optical depth (AOD) at 500 nm was 0.32±0.06, and the Ångström exponent ( α) was 0.73 ± 0.27. Aerosol optical properties revealed significant seasonal characteristics. Frequent sandstorms in MAM (March-April-May) resulted in the seasonal maximum AOD, 0.41 ± 0.04, and a relatively smaller α value, 0.44±0.04. The tourism seasons, JJA (June-July-August) and SON (September-October-November) coincide with serious emissions of small anthropogenic aerosols. While in DJF (December-January-February), the composition of the atmosphere was a mixture of dust particles and polluted aerosols released by domestic heating; the average AOD and α were 0.29 ± 0.02 and 0.66 ± 0.17, respectively. Different air masses exhibited different degrees of influence on the aerosol concentration over Dunhuang in different seasons. During MAM, ranges of AOD (0.11-1.18) and α (0.06-0.82) were the largest under the dust influence of northwest-short-distance air mass in the four trajectories. Urban aerosols transported by northwest-short-distance air mass accounted for a very large proportion in JJA and the mixed aerosols observed in SON were mainly conveyed by air masses from the west. In DJF, the similar ranges of AOD and α under the three air mass demonstrated the analogous diffusion effects on regional pollutants over Dunhuang.

  10. Distribution and diversity of rhizobia associated with wild soybean (Glycine soja Sieb. & Zucc.) in Northwest China.

    Science.gov (United States)

    Zhao, Liang; Fan, Miaochun; Zhang, Dehui; Yang, Ruiping; Zhang, Feilong; Xu, Lin; Wei, Xiuli; Shen, Yaoyao; Wei, Gehong

    2014-09-01

    A total of 155 nodule isolates that originated from seven sites in Northwest China were characterized by PCR-RFLP of the 16S rRNA gene and sequence analysis of multiple core genes (16S rRNA, recA, atpD, and glnII) in order to investigate the diversity and biogeography of Glycine soja-nodulating rhizobia. Among the isolates, 80 were Ensifer fredii, 19 were Ensifer morelense, 49 were Rhizobium radiobacter, and 7 were putative novel Rhizobium species. The phylogenies of E. fredii and E. morelense isolates in a concatenate tree (assembly of all housekeeping genes) were generally consistent with those in individual gene trees. However, incongruence was found in the phylogenies of the different genes of Rhizobium isolates, indicating that lateral transfer or recombination possibly occurred in these gene loci. Despite their species identity, all the isolates in this study formed a single lineage related to E. fredii in nodAand nifH gene phylogenies, which also indicated that the symbiotic genes were laterally transferred between different species. Biogeographic patterns were found at the species and strain genomic type levels, as revealed by BOXA1R fingerprinting, demonstrating that the evolution of rhizobial populations in different geographic locations was related to soil types, altitude and spatial effects. This study is the first to report that E. morelense, R. radiobacter, and Rhizobium sp. are microsymbionts of G. soja, as well as showing that the diversity of G. soja rhizobia is enhanced and new rhizobia have evolved in Northwest China.

  11. Estimation of net primary productivity using a process-based model in Gansu Province, Northwest China

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Peijuan; Xie, Donghui; Zhou, Yuyu; E, Youhao; Zhu, Qijiang

    2014-01-16

    The ecological structure in the arid and semi-arid region of Northwest China with forest, grassland, agriculture, Gobi, and desert, is complex, vulnerable, and unstable. It is a challenging and sustaining job to keep the ecological structure and improve its ecological function. Net primary productivity (NPP) modeling can help to improve the understanding of the ecosystem, and therefore, improve ecological efficiency. The boreal ecosystem productivity simulator (BEPS) model provides the possibility of NPP modeling in terrestrial ecosystem, but it has some limitations for application in arid and semi-arid regions. In this paper we improve the BEPS model, in terms of its water cycle by adding the processes of infiltration and surface runoff, to be applicable in arid and semi-arid regions. We model the NPP of forest, grass, and crop in Gansu Province as an experimental area in Northwest China in 2003 using the improved BEPS model, parameterized with moderate resolution remote sensing imageries and meteorological data. The modeled NPP using improved BEPS agrees better with the ground measurements in Qilian Mountain than that with original BEPS, with a higher R2 of 0.746 and lower root mean square error (RMSE) of 46.53 gC/m2 compared to R2 of 0.662 and RMSE of 60.19 gC/m2 from original BEPS. The modeled NPP of three vegetation types using improved BEPS show evident differences compared to that using original BEPS, with the highest difference ratio of 9.21% in forest and the lowest value of 4.29% in crop. The difference ratios between different vegetation types lie on the dependence on natural water sources. The modeled NPP in five geographic zones using improved BEPS are higher than those with original BEPS, with higher difference ratio in dry zones and lower value in wet zones.

  12. Current attitudes toward organ donation after cardiac death in northwest China

    Institute of Scientific and Technical Information of China (English)

    Pan Xiaoming; Liu Linjuan; Xiang Heli; Ding Chenguang; Ren Li; Xue Wujun

    2014-01-01

    Background People's attitude toward organ donation after cardiac death (DCD) has not come to an agreement in different countries and regions.Influenced by the local culture in China for thousands of years,the general public has different ideas about this issue.The purpose of this study was to investigate the current attitudes trend and characteristics of transplantation with organs donated after cardiac death in northwest China.Methods This largest single-center cohort study was performed by an interview or by telephone using a questionnaire.The family members of potential DCD donors were recruited from the First Affiliated Hospital,medical college of Xi'an Jiaotong University located in a metropolitan area of northwest China.The 12-item attitude questionnaire was specifically developed from the literature review with coordinator,physician,and donor's family feedback.The participants were asked to rate the queries on a 5-point Likert intensity scale.Results The 174 participants included 56 (32.2%) women and 118 (67.8%) men.Most people were aged between 41 and 50 years (n=63,36.2%),31 and 40 years (n=59,33.9%),and less than 30 years (n=36,20.7%).The top five attitudes of participants were the best person to suggest organ donation to a family was ranked as the DCD coordinator of Red Cross Organization (RCO,n=160,92%),donor is a hero (n=143,82.2%),honor to be a donor's family member (n=136,78.2%),improved relationship with colleagues (n=124,71.3%),and with recipient after donation (n=123,70.7%).The best person to suggest organ donation to a family was ranked as the coordinator of RCO (n=160,92%),doctor unrelated to transplantation (n=104,59.8%),social worker (n=36,20.7%),and doctor related to transplantation (n=25,14.4%).The top two reasons for non-consent to donation were that the family insisted on intact body after patient death and did not want to have surgery again (n=51,41.5%),and feared that they would be misunderstood by neighbors

  13. LATEST DEVONIAN (FAMENNIAN TO EARLIEST CARBONIFEROUS (TOURNAISIAN BRACHIOPODS FROM THE BACHU FORMATION OF THE TARIM BASIN, XINJIANG PROVINCE, NORTHWEST CHINA

    Directory of Open Access Journals (Sweden)

    Z Q. CHEN

    1999-07-01

    Full Text Available Brachiopods are described from two horizons of the Bachu Formation from the Bachu area of the Tarim Basin, Xinjiang Province, northwest China. We assign the brachiopods from the basal Bachu Formation to late Famennian and correlate those from its upper part to the Eochoristites-Martiniella Assemblage of South China, of early Tournaisian age. The brachiopod fauna of the Bachu Formation exhibits strong generic and specific links with coeval South Chinese faunas, suggesting a close biogeographical affinity with the South China block. Eleven species are described, including one new species, Ptychomaletoechia bachuensis sp. nov. 

  14. Modeling impacts of management alternatives on soil carbon storage of farmland in Northwest China

    Directory of Open Access Journals (Sweden)

    F. Zhang

    2006-05-01

    Full Text Available Long-term losses of soil organic carbon (SOC have been observed in many agriculture lands in Northwest China, one of the regions with the longest cultivation history in the world. The decline of SOC contents not only impaired the soil fertility but also increased the amount of carbon dioxide (CO2 emitted from terrestrial ecosystems into the atmosphere. However, quantifying the SOC losses at regional scale has long been remaining unsolved. A process-based model, Denitrification-Decomposition or DNDC, was adopted in the study to quantify impacts of farming management practices on SOC dynamics for a selected region, Shaanxi Province. The selected domain, with 3 million hectares of cropland across different climatic and farming management regimes, is representative for the major agricultural areas in Northwest China. The DNDC model was tested against long-term SOC dynamics observed at five agricultural sites in China. The agreement between the observed and modeled results indicate that DNDC was capable of capturing patterns and magnitudes of SOC changes across the climate zones, soil types, and management regimes in China. To quantify SOC dynamics for Shaanxi, we constructed a GIS database to hold all of the DNDC-required input information (e.g., weather, soil properties, crop acreage, and farming practices for all the farmland in the studied domain. Sensitivity tests indicated the spatial heterogeneity of soil properties, especially initial SOC content, was the major source of uncertainty for the modeled SOC dynamics at regional scale. The Most Sensitive Factor (MSF method was employed in the study to quantify the uncertainties produced from the upscaling process. The results from the regional simulations for Shaanxi indicated that (1 the overall 3 million hectares of farmland in the province was a source of atmospheric CO2 with 0.5 Tg C yr−1 lost in 2000 under the current farming

  15. Chemical composition, sources and secondary processes of aerosols in Baoji city of northwest China

    Science.gov (United States)

    Wang, Y. C.; Huang, R.-J.; Ni, H. Y.; Chen, Y.; Wang, Q. Y.; Li, G. H.; Tie, X. X.; Shen, Z. X.; Huang, Y.; Liu, S. X.; Dong, W. M.; Xue, P.; Fröhlich, R.; Canonaco, F.; Elser, M.; Daellenbach, K. R.; Bozzetti, C.; El Haddad, I.; Prévôt, A. S. H.; Canagaratna, M. R.; Worsnop, D. R.; Cao, J. J.

    2017-06-01

    Particulate air pollution is a severe environmental problem in China, affecting visibility, air quality, climate and human health. However, previous studies focus mainly on large cities such as Beijing, Shanghai, and Guangzhou. In this study, an Aerodyne Aerosol Chemical Speciation Monitor was deployed in Baoji, a middle size inland city in northwest China from 26 February to 27 March 2014. The non-refractory submicron aerosol (NR-PM1) was dominated by organics (55%), followed by sulfate (16%), nitrate (15%), ammonium (11%) and chloride (3%). A source apportionment of the organic aerosol (OA) was performed with the Sofi (Source Finder) interface of ME-2 (Multilinear Engine), and six main sources/factors were identified and classified as hydrocarbon-like OA (HOA), cooking OA (COA), biomass burning OA (BBOA), coal combustion OA (CCOA), less oxidized oxygenated OA (LO-OOA) and more oxidized oxygenated OA (MO-OOA), which contributed 20%, 14%, 13%, 9%, 23% and 21% of total OA, respectively. The contribution of secondary components shows increasing trends from clean days to polluted days, indicating the importance of secondary aerosol formation processes in driving particulate air pollution. The formation of LO-OOA and MO-OOA is mainly driven by photochemical reactions, but significantly influenced by aqueous-phase chemistry during periods of low atmospheric oxidative capacity.

  16. THE STUDY OF POPULATION GENETIC RELATION AMONG TEN ETHNIC GROUPS IN NORTHWEST CHINA

    Institute of Scientific and Technical Information of China (English)

    康龙丽; 金天博; 陈腾; 李生斌

    2004-01-01

    Objective To investigate the genetic relation among ten ethnic groups in northwest China. Methods Allele frequencies of six STR(short tandem repeat ) loci in D13S1358, VWA, FGA, D5S818, D13S317, and D7S820 were collected from Lasa Tibetan, Changdu Tibetan, Xian Han, Gansu Dongxiang, Gansu Yugu, Xinjiang Uygur, Ozbak, Kirgiz, Sibe, Ningxia Hui by the results of State Key laboratory, Forensic Science Department, school of medical, Xian Jiaotong University and internet biological information data bank, and compared with that of the Mongolian, Zhuang in China, and White and Negro in USA. The polymorphism index (H, DP, PPE, PIC) and genetic distance, then the phylogenetic tree of all population were reported. Results The resulting tree topology exhibited strong geographic and racial partitioning consistent with that obtained with HLA and classical genetic polymorphisms. Conclusion The results suggest that forensic STR loci may be particularly powerful tools and provide the necessary fine resolution for the reconstruction of recent human evolutionary history.

  17. Geochemical characteristics of fossil Solenites murrayana cuticles from the Jurassic in Lanzhou, northwest China

    Energy Technology Data Exchange (ETDEWEB)

    Sun, B.N.; Yan, D.F.; Xie, S.P.; Shi, Y.J.; Zhang, C.J.; Lin, Z.C. [Lanzhou University, Lanzhou (China)

    2006-07-01

    Through geochemical analysis on cuticles of the Jurassic fossil Solenites murrayuna L. et H. from the Yaojie Coalfield in Lanzhou, northwest China, and by comparison of geochemical features with its nearest living equivalent, Ginkgo biloba, we show that the characteristics of organic matter of the fossil plant cuticles accord with evolutionary features of asphalt in oil formation. The content analysis of organic matter indicates that the geochemistry is equivalent to rotten mud-sapropel humus types from Mesozoic and Cenozoic source rock in China. Some analysis data of organic matter indicate that Solenites murrayana cuticles are in a low mature stage, which coincides with the hydrocarbon generation model of cutinite in coal. Moreover, distribution features of soluble organic matter of cuticles show that fossil plant cuticles have a definite action in forming terrestrial high-wax oil, which has testified the contribution of high plants to waxness. The present study proves that Ginkgophytes abundant in the Jurassic were a high potential plant in the formation of coal-bed hydrocarbon.

  18. Early Tertiary plate reconstructions for the South China Sea region: constraints from northwest Borneo

    Science.gov (United States)

    Gower, Robert J. W.

    Previous plate reconstructions and tectonic syntheses for the southeast Asia region (Leichti et al. 1960, Ben Avraham and Uyeda 1973, Hamilton 1979, Holloway 1982, Taylor and Hayes 1982) have all highlighted the problems of correlating events in northwest Borneo with contemporaneous extension of the South China Sea. Theoretical modelling of crustal scale deformation in Asia during the Tertiary (Tapponnier et al. 1982) following India's collision with Asia suggested that the opening of the South China Sea basin accommodated major sinistral displacement. Haile (1973) and Hamilton (1979) have proposed that active subduction of oceanic crust beneath northwestern Borneo during the late Cretaceous and early Tertiary was associated with the development of a major arcuate accretionary complex, the "Crocker-Rajang" complex (Haile 1973), which is exposed over a large area of West Malaysia. Contemporaneous outer arc basin sedimentation in west Sarawak and eastern Kalimantan is consistent with a southeasterly dipping orientation of subduction at the margin. The duration of subduction is poorly constrained, but the initiation of major clastic depocenter in the Baram-Belait area during the early Miocene (Brondjik 1963), indicates a major change in sedimentation and deformational style at the northwestern Bornea continental margin. Pre-Miocene geological and paleomagnetic evidence from Borneo is inconsistent with the simple model of estrusion tectonics and suggests that Borneo and Malaya were separate microplates during the early Tertiary.

  19. Pharmacists' perception of pharmaceutical care in community pharmacy: a questionnaire survey in Northwest China.

    Science.gov (United States)

    Fang, Yu; Yang, Shimin; Feng, Bianling; Ni, Yufei; Zhang, Kanghuai

    2011-03-01

    The aim of this study was to explore the perceptions of community pharmacists towards the concept of pharmaceutical care, implementing frequencies of pharmaceutical care, and barriers to implementation of pharmaceutical care in China. A 38-item self-completion pre-tested questionnaire was administered to a quota sample of 130 pharmacists in community pharmacies in Xi'an, Shaanxi Province, northwest China in April 2008. Main outcome measures included understanding of pharmaceutical care; perceived frequency of pharmaceutical care activities; attitude towards pharmaceutical care; barriers to implementation of pharmaceutical care. A response rate of 77.7% (101/130) was achieved. The data were analysed descriptively. Factor analysis was used to explore potential barriers to the provision of pharmaceutical care. Respondents' understanding of the definition of pharmaceutical care was not entirely satisfactory: it was widely but incorrectly seen as a medication counselling service and many pharmacists appeared to misunderstand their role in the process. Respondents spent most of their work time performing prescription checks and providing patients with directions for drug administration, dosage, and precautions, but they tended to ignore health promotion within and outside of pharmacy settings. Factor analysis suggested four factors influencing the implementation of pharmaceutical care in the surveyed community pharmacies: lack of external conditions for developing or providing pharmaceutical care, lack of time and skills, absence of information and economic incentive, and lack of full support from other health professionals, with a cumulative variance of 64.7%. Cronbach's alpha for the four factors was 0.71, 0.72, 0.69 and 0.74, respectively. Although the respondent pharmacists had a certain degree of understanding of the definition, aim, function and use of pharmaceutical care, and carried out some activities currently, a range of barriers need to be overcome before

  20. Unconformity structures controlling stratigraphic reservoirs in the north-west margin of Junggar basin, North-west China

    Science.gov (United States)

    Wu, Kongyou; Paton, Douglas; Zha, Ming

    2013-03-01

    Tectonic movements formed several unconformities in the north-west margin of the Junggar basin. Based on data of outcrop, core, and samples, the unconformity is a structural body whose formation associates with weathering, leaching, and onlap. At the same time, the structural body may be divided into three layers, including upper layer, mid layer, and lower layer. The upper layer with good primary porosity serves as the hydrocarbon migration system, and also accumulates the hydrocarbon. The mid layer with compactness and ductility can play a role as cap rock, the strength of which increases with depth. The lower layer with good secondary porosity due to weathering and leaching can form the stratigraphic truncation traps. A typical stratigraphic reservoir lying in the unconformity between the Jurassic and Triassic in the north-west margin of the Junggar basin was meticulously analyzed in order to reveal the key controlling factors. The results showed that the hydrocarbon distribution in the stratigraphic onlap reservoirs was controlled by the onlap line, the hydrocarbon distribution in the stratigraphic truncation reservoirs was confined by the truncation line, and the mid layer acted as the key sealing rock. So a conclusion was drawn that "two lines (onlap line and truncation line) and a body (unconformity structural body)" control the formation and distribution of stratigraphic reservoirs.

  1. Unconformity structures controlling stratigraphic reservoirs in the north-west margin of Junggar basin, North-west China

    Institute of Scientific and Technical Information of China (English)

    Kongyou WU; Douglas PATON; Ming ZHA

    2013-01-01

    Tectonic movements formed several unconformities in the north-west margin of the Junggar basin.Based on data of outcrop,core,and samples,the unconformity is a structural body whose formation associates with weathering,leaching,and onlap.At the same time,the structural body may be divided into three layers,including upper layer,mid layer,and lower layer.The upper layer with good primary porosity serves as the hydrocarbon migration system,and also accumulates the hydrocarbon.The mid layer with compactness and ductility can play a role as cap rock,the strength of which increases with depth.The lower layer with good secondary porosity due to weathering and leaching can form the stratigraphic truncation traps.A typical stratigraphic reservoir lying in the unconformity between the Jurassic and Triassic in the north-west margin of the Junggar basin was meticulously analyzed in order to reveal the key controlling factors.The results showed that the hydrocarbon distribution in the stratigraphic onlap reservoirs was controlled by the onlap line,the hydrocarbon distribution in the stratigraphic truncation reservoirs was confined by the truncation line,and the mid layer acted as the key sealing rock.So a conclusion was drawn that "two lines (onlap line and truncation line) and a body (unconformity structural body)" control the formation and distribution of stratigraphic reservoirs.

  2. First report of Toxoplasma gondii infection in market-sold adult chickens, ducks and pigeons in northwest China

    OpenAIRE

    Cong Wei; Huang Si-Yang; Zhou Dong-Hui; Xu Min-Jun; Wu Song-Ming; Yan Chao; Zhao Quan; Song Hui-Qun; Zhu Xing-Quan

    2012-01-01

    Abstract Background Toxoplasma gondii infection is a global concern, affecting a wide range of warm-blooded animals and humans worldwide, including poultry. Domestic and companion birds are considered to play an important role in the transmission of T. gondii to humans and other animals. However, little information on T. gondii infection in domestic birds in Lanzhou, northwest China was available. Therefore, this study was performed to determine the seroprevalence of T. gondii infection in do...

  3. First report of Toxoplasma gondii infection in market-sold adult chickens, ducks and pigeons in northwest China

    Directory of Open Access Journals (Sweden)

    Cong Wei

    2012-06-01

    Full Text Available Abstract Background Toxoplasma gondii infection is a global concern, affecting a wide range of warm-blooded animals and humans worldwide, including poultry. Domestic and companion birds are considered to play an important role in the transmission of T. gondii to humans and other animals. However, little information on T. gondii infection in domestic birds in Lanzhou, northwest China was available. Therefore, this study was performed to determine the seroprevalence of T. gondii infection in domestic birds in Lanzhou, northwest China. Methods In the present study, the seroprevalence of T. gondii antibodies in 413 (305 caged and 108 free-range adult chickens, 334 (111 caged and 223 free-range adult ducks and 312 adult pigeons in Lanzhou, northwest China, were examined using the modified agglutination test (MAT. Results 30 (7.26% chickens, 38 (11.38% ducks and 37 (11.86% pigeons were found to be positive for T. gondii antibodies at the cut-off of 1:5. The prevalences in caged and free-range chickens were 6.23% and 10.19% respectively, however, statistical analysis showed that the difference was not significant (P > 0.05. The seroprevalences in caged and free-range ducks were 6.31% and 13.90% respectively, but the difference was not statistically significant (P > 0.05. Conclusions The results of the present survey indicated the presence of T. gondii infection in adult chickens, ducks and pigeons sold for meat in poultry markets in Lanzhou, northwest China, which poses a potential risk for T. gondii infection in humans and other animals in this region. This is the first seroprevalence study of T. gondii infection in domestic birds in this region.

  4. An input-output table based analysis on the virtual water by sectors with the five northwest provinces in China

    Science.gov (United States)

    Shi, Chenchen; Zhan, Jinyan

    Virtual water refers to the volumes of water required to produce a commodity or service. It reflects human's actual consumption of water resources and therefore has certain significance in water resources management. Over the years, the concept of virtual water has caught the attentions of water manager and decision maker. In order to utilize this concept, the accounting and estimation of virtual water is the foundation that lies in this issue. Till now, the accounting methods mainly include the method provided by Food and Agriculture Organization of the United Nations (FAO), water footprint and input-output analysis method. In this paper, we chose Northwest China, which is a typical arid region that is facing with rapid economic development, as the study area and built an Input-Output (IO) analysis method to estimate virtual water among different industry sectors in the northwest China. The accounting and estimation results could be used to give suggestions to increase water use efficiency and promote virtual water trade in the study area. Comparison of the proposed method with other prevailing method was also analyzed. The introduced method could be utilized for accounting and estimation of virtual water by sectors, with its superiority in characterizing industrial water consumption and the accounting results could lend certain credence to the water resource management and industrial transformation for the future economic development of northwest China.

  5. Dermanyssidae insects in northwest China%西北地区皮刺螨科昆虫初报

    Institute of Scientific and Technical Information of China (English)

    罗芳; 刘增加; 张继军

    2011-01-01

    目的 研究西北地区皮刺螨科昆虫的种类与地理分布.方法 宿主体检螨法和巢穴检螨法.结果 记述西北地区皮刺螨科Dermanyssidae 6属36种,即异皮螨属Allodermanyssus 1种、皮刺螨属Dermanyssus 1种、赫刺螨属Hirstionyssus 27种、鼠刺螨属Myonyssus 1种、禽刺螨属Ornithonysus 2种、肪刺螨属Steatonyssus4种.结论 初步明确西北地区皮刺螨科昆虫的种类与分布,为深入研究与防控提供了科学依据.%Objective To study the species and geographical distribution of Dermanyssidae in Northwest China. Method Using the methods of mite inspection of host surface and nest Results There were 6 genera and 36 species of Dermanyssidae in the Northwest China have been recorded, among them, 1 species of Allodermanyssus, 1 species of Der-manyssus, 27 species of Hirstionyssus Fonseca, 1 species of Myonyssus Tiraboschi, 2 species of Omithonyssus and 4 species of Steatonyssus. Conclusions This article initial identified the species and geographical distribution of Dermanyssidae in Northwest China and provide scientific basis for lucubrating and prevention and control the insect

  6. An observed connection between wintertime temperature anomalies over Northwest China and weather regime transitions in North Atlantic

    Science.gov (United States)

    Li, Chao; Zhang, Qingyun

    2015-04-01

    In this study, the association between wintertime temperature anomalies over Northwest China and the weather regime transitions in North Atlantic on synoptic scale is analyzed by using observational surface air temperature (SAT) data and atmospheric reanalysis data. Daily SAT anomaly and duration time are used in order to define SAT anomaly cases. Differences with regard to the circulation anomalies over the Ural Mountains and the upstream North Atlantic area are evident. It is found that the colder than normal SAT is caused by the enhanced Ural high and associated southward flow over Northwest China. Time-lagged composites reveal possible connections between the SAT anomalies and the different development phases of the North Atlantic Oscillation (NAO). The Ural highs tend to be strengthened during the negative phase of NAO (NAO-) to Atlantic ridge transition, which are closely related to the downstream-propagating Rossby wave activity. The opposite circulation patterns are observed in the warm SAT cases. A cyclonic circulation anomaly is distinctly enhanced over the Urals during the positive phase of NAO (NAO+) to Scandinavian blocking transition, which would cause warmer SAT over Northwest China. Further analyses suggest that the intensified zonal wind over North Atlantic would favor the NAO- to Atlantic ridge transition, while the weakened zonal wind may be responsible for the transition between NAO+ and Scandinavian blocking.

  7. An Observed Connection Between Wintertime Temperature Anomalies over Northwest China and Weather Regime Transitions in North Atlantic

    Institute of Scientific and Technical Information of China (English)

    李超; 张庆云

    2015-01-01

    In this study, the association between wintertime temperature anomalies over Northwest China and the weather regime transitions in North Atlantic on synoptic scale is analyzed by using observational surface air temperature (SAT) data and atmospheric reanalysis data. Daily SAT anomaly and duration time are used in order to defi ne SAT anomaly cases. Diff erences with regard to the circulation anomalies over the Ural Mountains and the upstream North Atlantic area are evident. It is found that the colder than normal SAT is caused by the enhanced Ural high and associated southward fl ow over Northwest China. Time-lagged composites reveal possible connections between the SAT anomalies and the diff erent development phases of the North Atlantic Oscillation (NAO). The Ural highs tend to be strengthened during the negative phase of NAO (NAO–) to Atlantic ridge transition, which are closely related to the downstream-propagating Rossby wave activity. The opposite circulation patterns are observed in the warm SAT cases. A cyclonic circulation anomaly is distinctly enhanced over the Urals during the positive phase of NAO (NAO+) to Scandinavian blocking transition, which would cause warmer SAT over Northwest China. Further analyses suggest that the intensifi ed zonal wind over North Atlantic would favor the NAO–to Atlantic ridge transition, while the weakened zonal wind may be responsible for the transition between NAO+and Scandinavian blocking.

  8. Dust deposition and ambient PM10 concentration in northwest China: spatial and temporal variability

    Science.gov (United States)

    Zhang, Xiao-Xiao; Sharratt, Brenton; Chen, Xi; Wang, Zi-Fa; Liu, Lian-You; Guo, Yu-Hong; Li, Jie; Chen, Huan-Sheng; Yang, Wen-Yi

    2017-02-01

    Eolian dust transport and deposition are important geophysical processes which influence global bio-geochemical cycles. Currently, reliable deposition data are scarce in central and east Asia. Located at the boundary of central and east Asia, Xinjiang Province of northwestern China has long played a strategic role in cultural and economic trade between Asia and Europe. In this paper, we investigated the spatial distribution and temporal variation in dust deposition and ambient PM10 (particulate matter in aerodynamic diameter ≤ 10 µm) concentration from 2000 to 2013 in Xinjiang Province. This variation was assessed using environmental monitoring records from 14 stations in the province. Over the 14 years, annual average dust deposition across stations in the province ranged from 255.7 to 421.4 t km-2. Annual dust deposition was greater in southern Xinjiang (663.6 t km-2) than northern (147.8 t km-2) and eastern Xinjiang (194.9 t km-2). Annual average PM10 concentration across stations in the province varied from 100 to 196 µg m-3 and was 70, 115 and 239 µg m-3 in northern, eastern and southern Xinjiang, respectively. The highest annual dust deposition (1394.1 t km-2) and ambient PM10 concentration (352 µg m-3) were observed in Hotan, which is located in southern Xinjiang and at the southern boundary of the Taklamakan Desert. Dust deposition was more intense during the spring and summer than other seasons. PM10 was the main air pollutant that significantly influenced regional air quality. Annual average dust deposition increased logarithmically with ambient PM10 concentration (R2 ≥ 0.81). While the annual average dust storm frequency remained unchanged from 2000 to 2013, there was a positive relationship between dust storm days and dust deposition and PM10 concentration across stations. This study suggests that sand storms are a major factor affecting the temporal variability and spatial distribution of dust deposition in northwest China.

  9. An integrated multiscale river basin observing system in the Heihe River Basin, northwest China

    Science.gov (United States)

    Li, X.; Liu, S.; Xiao, Q.; Ma, M.; Jin, R.; Che, T.

    2015-12-01

    Using the watershed as the unit to establish an integrated watershed observing system has been an important trend in integrated eco-hydrologic studies in the past ten years. Thus far, a relatively comprehensive watershed observing system has been established in the Heihe River Basin, northwest China. In addition, two comprehensive remote sensing hydrology experiments have been conducted sequentially in the Heihe River Basin, including the Watershed Allied Telemetry Experimental Research (WATER) (2007-2010) and the Heihe Watershed Allied Telemetry Experimental Research (HiWATER) (2012-2015). Among these two experiments, an important result of WATER has been the generation of some multi-scale, high-quality comprehensive datasets, which have greatly supported the development, improvement and validation of a series of ecological, hydrological and quantitative remote-sensing models. The goal of a breakthrough for solving the "data bottleneck" problem has been achieved. HiWATER was initiated in 2012. This project has established a world-class hydrological and meteorological observation network, a flux measurement matrix and an eco-hydrological wireless sensor network. A set of super high-resolution airborne remote-sensing data has also been obtained. In addition, there has been important progress with regard to the scaling research. Furthermore, the automatic acquisition, transmission, quality control and remote control of the observational data has been realized through the use of wireless sensor network technology. The observation and information systems have been highly integrated, which will provide a solid foundation for establishing a research platform that integrates observation, data management, model simulation, scenario analysis and decision-making support to foster 21st-century watershed science in China.

  10. Common and Privatized: Conditions for Wise Management of Matsutake Mushrooms in Northwest Yunnan Province, China

    Directory of Open Access Journals (Sweden)

    Xuefei Yang

    2009-12-01

    Full Text Available Since Hardin's (1968 paper on the "Tragedy of the Commons," property rights of common-pool resources have been a central concern for natural resource management scholars. Matsutake, a common-pool resource, is an economically important mushroom in several locations around the world. Driven by growing international demand over the last few decades, matsutake management is a relatively new practice both for local communities and government agencies. In Northwest Yunnan, China, one of the most productive areas for matsutake globally, numerous local practices and systems have emerged in the last two to three decades. In this study, we investigate the differences between management systems in eight communities and the factors associated with them. The methods used for field research included key-informant interviews, household surveys, and questionnaires. Three main management patterns were identified through use of statistical clustering based on indicators such as physical environment, resource characteristics, tenure arrangements, regulations and implementation, harvesting behavior, income, and market regulation. It was found that private access - the principal characteristic of which is the exclusive use of resources - results in more income at lower labor cost per household than either of the other open-access management patterns. Even though under the context of ongoing Second Forest Tenure Reform in China - in which collective forest privatization is the key task - application of private-access regimes is limited because of site conditions including physical, institutional, and market environments. Common-access management systems have advantages in terms of managing conflict and balancing equity needs. No matter the type of access right, the key issue for wise matsutake management is institutional. Locally rooted innovative strategies should be encouraged, and institutional capacity building should be carried out to support innovations in

  11. Seed dispersal and germination traits of 70 plant species inhabiting the Gurbantunggut Desert in northwest China.

    Science.gov (United States)

    Liu, Huiliang; Zhang, Daoyuan; Yang, Xuejun; Huang, Zhenying; Duan, Shimin; Wang, Xiyong

    2014-01-01

    Seed dispersal and germination were examined for 70 species from the cold Gurbantunggut Desert in northwest China. Mean and range (3 orders of magnitude) of seed mass were smaller and narrower than those in other floras (5-8 orders of magnitude), which implies that selection favors relatively smaller seeds in this desert. We identified five dispersal syndromes (anemochory, zoochory, autochory, barochory, and ombrohydrochory), and anemochorous species were most abundant. Seed mass (F = 3.50, P = 0.01), seed size (F = 8.31, P seed shape (F = 2.62, P = 0.04) differed significantly among the five dispersal syndromes and barochorous species were significantly smaller and rounder than the others. There were no significant correlations between seed mass (seed weight) (P = 0.15), seed size (P = 0.38), or seed shape (variance) (P = 0.95) and germination percentage. However, germination percentages differed significantly among the dispersal syndromes (F = 3.64, P = 0.01) and seeds of ombrohydrochorous species had higher germination percentages than those of the other species. In the Gurbantunggut Desert, the percentage of species with seed dormancy was about 80%. In general, our studies suggest that adaptive strategies in seed dispersal and germination of plants in this area are closely related to the environment in which they live and that they are influenced by natural selection forces.

  12. Seed Dispersal and Germination Traits of 70 Plant Species Inhabiting the Gurbantunggut Desert in Northwest China

    Directory of Open Access Journals (Sweden)

    Huiliang Liu

    2014-01-01

    Full Text Available Seed dispersal and germination were examined for 70 species from the cold Gurbantunggut Desert in northwest China. Mean and range (3 orders of magnitude of seed mass were smaller and narrower than those in other floras (5–8 orders of magnitude, which implies that selection favors relatively smaller seeds in this desert. We identified five dispersal syndromes (anemochory, zoochory, autochory, barochory, and ombrohydrochory, and anemochorous species were most abundant. Seed mass (F=3.50, P=0.01, seed size (F=8.31, P<0.01, and seed shape (F=2.62, P=0.04 differed significantly among the five dispersal syndromes and barochorous species were significantly smaller and rounder than the others. There were no significant correlations between seed mass (seed weight (P=0.15, seed size (P=0.38, or seed shape (variance (P=0.95 and germination percentage. However, germination percentages differed significantly among the dispersal syndromes (F=3.64, P=0.01 and seeds of ombrohydrochorous species had higher germination percentages than those of the other species. In the Gurbantunggut Desert, the percentage of species with seed dormancy was about 80%. In general, our studies suggest that adaptive strategies in seed dispersal and germination of plants in this area are closely related to the environment in which they live and that they are influenced by natural selection forces.

  13. Simulating the Effect of Climate Change on Vegetation Zone Distribution on the Loess Plateau, Northwest China

    Directory of Open Access Journals (Sweden)

    Guoqing Li

    2015-06-01

    Full Text Available A risk assessment of vegetation zone responses to climate change was conducted using the classical Holdridge life zone model on the Loess Plateau of Northwest China. The results show that there are currently ten vegetation zones occurring on the Loess Plateau (1950–2000, including alvar desert, alpine wet tundra, alpine rain tundra, boreal moist forest, boreal wet forest, cool temperate desert, cool temperate desert scrub, cool temperate steppe, cool temperate moist forest, warm temperate desert scrub, warm temperate thorn steppe, and warm temperate dry forest. Seventy years later (2070S, the alvar desert, the alpine wet tundra and the cool temperate desert will disappear, while warm temperate desert scrub and warm temperate thorn steppe will emerge. The area proportion of warm temperate dry forest will expand from 12.2% to 22.8%–37.2%, while that of cool temperate moist forest will decrease from 18.5% to 6.9%–9.5%. The area proportion of cool temperate steppe will decrease from 51.8% to 34.5%–51.6%. Our results suggest that future climate change will be conducive to the growth and expansion of forest zones on the Loess Plateau, which can provide valuable reference information for regional vegetation restoration planning and adaptive strategies in this region.

  14. Genetic polymorphisms of VIP variants in the Tajik ethnic group of northwest China.

    Science.gov (United States)

    Zhang, Jiayi; Jin, Tianbo; Yunus, Zulfiya; Li, Xiaolan; Geng, Tingting; Wang, Hong; Cui, Yali; Chen, Chao

    2014-09-30

    Individual response to medications varies significantly among different populations, and great progress in understanding the molecular basis of drug action has been made in the past 50 years. The field of pharmacogenomics seeks to elucidate inherited differences in drug disposition and effects. While we know that different populations and ethnic groups are genetically heterogeneous, we have not found any pharmacogenomics information regarding minority groups, such as the Tajik ethnic group in northwest China. We genotyped 85 Very Important Pharmacogene (VIP) variants selected from PharmGKB in 100 unrelated, healthy Tajiks from the Xinjiang Uygur Autonomous Region and compared our data with HapMap data from four major populations around the world: Han Chinese (CHB), Japanese in Tokyo (JPT), Utah Residents with Northern and Western European Ancestry (CEU), and Yorubia in Ibadan, Nigeria (YRI). We found that Tajiks differed from CHB, JPT and YRI in 30, 32, and 32 of the selected VIP genotypes respectively (p ethnic group and provide a theoretical basis for safer drug administration that may be useful for diagnosing and treating disease in this population.

  15. Mantle-derived helium in foreland basins in Xinjiang, Northwest China

    Science.gov (United States)

    Xu, Sheng; Zheng, Guodong; Zheng, Jianjing; Zhou, Shixin; Shi, Pilong

    2017-01-01

    Hydrocarbon-rich natural gases from the Tarim, Junggar, Turpan-Hami and Santanghu basins in Xinjiang, Northwest China have measured 3He/4He ratios from 0.01 to 0.6 times higher than the atmospheric value, indicating 0-7% helium derived from the mantle. The mantle-derived helium is high in foreland basins associated with the Tianshan, Kunlun and Zhayier-Halalate orogenic mountains, but low towards the center of basins. This spatial distribution suggests that the mantle-derived helium originates either from fluids or small scale melts in the upper asthenospheric or lithospheric mantle which have found pathways into the root zones of the major faults defining these mountains, but do not significantly move into the basins themselves. During upward transport to near the surface, the mantle-derived helium is significantly diluted by radiogenic helium produced in the crust. Despite the lack of recent magmatic activity or extensional tectonics within the basins, this pattern shows strong evidence that the major faults play an important role in mantle-derived components degassing from the mantle to the surface.

  16. Estimation of wind erosion from construction of a railway in arid Northwest China

    Directory of Open Access Journals (Sweden)

    Benli Liu

    2017-06-01

    Full Text Available A state-of-the-art wind erosion simulation model, the Wind Erosion Prediction System and the United States Environmental Protection Agency's AP 42 emission factors formula, were combined together to evaluate wind-blown dust emissions from various construction units from a railway construction project in the dry Gobi land in Northwest China. The influence of the climatic factors: temperature, precipitation, wind speed and direction, soil condition, protective measures, and construction disturbance were taken into account. Driven by daily and sub-daily climate data and using specific detailed management files, the process-based WEPS model was able to express the beginning, active, and ending phases of construction, as well as the degree of disturbance for the entire scope of a construction project. The Lanzhou-Xinjiang High-speed Railway was selected as a representative study because of the diversities of different climates, soil, and working schedule conditions that could be analyzed. Wind erosion from different working units included the building of roadbeds, bridges, plants, temporary houses, earth spoil and barrow pit areas, and vehicle transportation were calculated. The total wind erosion emissions, 7406 t, for the first construction area of section LXS-15 with a 14.877 km length was obtained for quantitative analysis. The method used is applicable for evaluating wind erosion from other complex surface disturbance projects.

  17. Modelling Snowmelt Runoff under Climate Change Scenarios in an Ungauged Mountainous Watershed, Northwest China

    Directory of Open Access Journals (Sweden)

    Yonggang Ma

    2013-01-01

    Full Text Available An integrated modeling system has been developed for analyzing the impact of climate change on snowmelt runoff in Kaidu Watershed, Northwest China. The system couples Hadley Centre Coupled Model version 3 (HadCM3 outputs with Snowmelt Runoff Model (SRM. The SRM was verified against observed discharge for outlet hydrological station of the watershed during the period from April to September in 2001 and generally performed well for Nash-Sutcliffe coefficient (EF and water balance coefficient (RE. The EF is approximately over 0.8, and the water balance error is lower than ± 10%, indicating reasonable prediction accuracy. The Statistical Downscaling Model (SDSM was used to downscale coarse outputs of HadCM3, and then the downscaled future climate data were used as inputs of the SRM. Four scenarios were considered for analyzing the climate change impact on snowmelt flow in the Kaidu Watershed. And the results indicated that watershed hydrology would alter under different climate change scenarios. The stream flow in spring is likely to increase with the increased mean temperature; the discharge and peck flow in summer decrease with the decreased precipitation under Scenarios 1 and 2. Moreover, the consideration of the change in cryosphere area would intensify the variability of stream flow under Scenarios 3 and 4. The modeling results provide useful decision support for water resources management.

  18. [Root architecture of two desert plants in central Hexi Corridor of Northwest China].

    Science.gov (United States)

    Shan, Li-Shan; Li, Yi; Ren, Wei; Su, Shi-Ping; Dong, Qiu-Lian; Geng, Dong-Mei

    2013-01-01

    In this study, the root systems of desert plant species Reaumuria soongorica and Nitraria tangutorum in the central Hexi Corridor of Northwest China were excavated by shovel, and the characteristics of the plant root architecture were analyzed by using topology and fractal theory. The root topological indices of the two desert plants were small, and the root branching patterns were herringbone-like. The roots of the two desert plants had obvious fractal characteristics, with the fractal dimension of R. soongorica and N. tangutorum being (1.18 +/- 0.04) and (1.36 +/- 0.06), respectively. The root fractal dimension and fractal abundance were significantly positively correlated with the root average link length. The root average link lengths of the two plants were long, which enlarged the plants' effective nutrition space, and thus, made the plants adapt to the dry and infertile soil environment. The sums of the root cross-sectional areas before and after the root bifurcation of the two desert plants were equal, which verified the principle of Leonardo da Vinci. A total of 17 parameters of root architecture were analyzed by the principal component analysis. The parameters of root topological structure, numbers of root links, stepwise branching ratio, and root diameter could well present the root architecture characteristics of the two desert plants.

  19. [Land use pattern change in Ejin Delta of Northwest China during 1930-2010].

    Science.gov (United States)

    Nian, Yan-yun; Wang, Xiao-li; Chen, Lu

    2015-03-01

    The land use and landscape pattern in the lower reaches of the arid inland river basin is meaningful to water resource allocation. Based on the land use data in 1930, 1961, 1990, 2000, 2010, the purpose of this study was to quantitatively analyze the change of landscape pattern in the Ejin Delta in the lower reaches of the Heihe River Basin, a typical inland river basin in Northwest China. The results showed that the desert area accounted for 73.4% of the total research area in 2010, and the grassland 20.8%. During the past 80 years, the grassland, farmland and construction land increased. The transformation of land use types were characterized by switching to farmland and construction land. The fragmentation and. diversity of the landscape increased, while the dominance of the landscape decreased. The landscape pattern obviously lied on the water resource and had regional diversity. Land use changes tended to make the landscape well-distributed, diverse and fragmentized. At last, the driving factors and ecological environment effects of land use change were discussed. In a word, to ensure harmonious development between human and eco-hydrology, suggestions such as planning ecological resettlement, limiting farmland area, developing precision agriculture and increasing the proportion of ecological water use should be put forward.

  20. [Ecological and economic harmony evaluation and spatial evolution of the Hexi corridor, northwest China].

    Science.gov (United States)

    Liu, Hai-long; Shi, Pei-ji; Li, Sheng-mei; Tong, Hua-li; Nie, Xiao-ying; Wei, Wei

    2014-12-01

    The relationship between economic development and environment and the evolution characteristics of spatial pattern in Hexi Corridor of Northwest China were analyzed based on Landsat images in 1985, 1995, 2000 and 2011 with twenty counties in Hexi Corridor chosen as the basic research units. The ecological economic harmony during 1985-2011 was estimated according to ESV (ecosystem services value) and EEH (ecological and economic harmony) index with the ecosystem services value estimation methods. The results showed that the land type of the study area dramatically changed during the study period, the grassland decreased badly, and the construction land and cultivated land increased quickly. The ESV showed an overall downward trend, especially in the Shiyang River basin and the middle of Heihe River. The ESV in the Shule River basin in this period. After 2000, the economic growth speeded up visibly in the study area. The economic development concentrated in the resource-based cities and regional central cities, and declined from the center of corridor to the both sides. The ecological-economic relation in Hexi Corridor experienced a transformation of "preliminary deterioration--further deterioration--low grade coordination". The EEH had large changes in the Shiyang River basin and the middle of Heihe River, which experienced a transformation of "conflict--more conflicts--less conflicts", however, there was little change in Shule River basin. The development mode and the comprehensive reclamation of Shiyang River basin and Heihe River basin had a significant influence on the regional ecological and economic harmony.

  1. Characteristics of meteorological drought pattern and risk analysis for maize production in Xinjiang, Northwest China

    Science.gov (United States)

    Li, Cheng; Wang, Ranghui; Ning, Husen; Luo, Qinghong

    2017-08-01

    Xinjiang is an important maize cultivation area in Northwest China. Investigating the relationship between meteorological drought and climate-driven maize yield can help to mitigate the negative impacts of drought on agricultural production in Xinjiang. In this study, multi-source data, including meteorological, agricultural, and socio-economic data, are collected to analyze the spatiotemporal patterns of drought and assess drought disaster risk. The standardized precipitation evapotranspiration index is calculated to classify different drought grades in the study area. The main results are as follows: (1) the relationship between drought and climate-driven maize yield is determined using a stepwise regression analysis, which indicates that drought conditions occurring from May to July are crucial for the yield in Xinjiang; (2) the modified Mann-Kendall test detects that the frequency-intensity-coverage of drought from May to July shows a decreasing tendency as a whole in the study area; (3) the correlation analysis shows that the multivariate ENSO index may be the dominant force in regional drought evolution; and (4) a drought disaster risk assessment system is constructed based on principles of natural disaster management. The drought disaster risk is higher in southwestern and northwestern Xinjiang, areas that should deserve more attention.

  2. Ecological and Economic System Health Assessment Based on Fuzzy Set Pair Analysis: A Case Study of Northwest Region, China%Ecological and Economic System Health Assessment Based on Fuzzy Set Pair Analysis: A Case Study of Northwest Region, China

    Institute of Scientific and Technical Information of China (English)

    Chen Junfei; Zhou Xiaolan; Wang Huimin

    2012-01-01

    Due to the increasingly serious environmental pollution and destruction, especially humans' unreasonable activities, the ecological and economic system (EES) issues of Northwest region in China have attracted more and more attention of the researchers. Aiming at evaluating its ecological and economic system health, a multi-objective evaluation framework called Pressure- State-Response (PSR) was established to. describe the ecological and economic health situations. Meanwhile, an integrative set pair model combining set pair analysis (SPA) and fuzzy analytic hierarchy process (FAHP) was proposed to assess the ecological and economic system. Then the EES status of five northwest provinces (Shanxi, Gansu, Qinghai, Ningxia and Xinjiang) of Northwest region in China was evaluated during 1985 to 2009. The EES development trends of five provinces are obtained. In general, the health values of five provinces showed a rising trend. The health values of five provinces grew rapidly during 1985 to 2000. After 2000, the health values of five provinces still followed the present growth trend, but the growth is relatively smooth. The results show that the method proposed is effective for assessing the health of ecological and economic system.

  3. Apcocynum Pictum and Sustainable Agriculture Along the Tarim River In Arid Northwest, China

    Science.gov (United States)

    Aihemaitijiang, R.

    2014-12-01

    Water scarcity and population increase have been a major limiting factor in oasis development along the Tarim River in Xinjiang, Northwest China which has very continental and dry climate, and all the agriculture and livelihoods depend on glacier melt water from Tarim River. Due to vast land reclamation along the Tarim River to grow cotton, native plant species are facing a severe competition for water, which is essential for their survival. Decreasing river runoff and inefficient water use practices by agriculture and industry has exacerbated already serious situation even worse. In addition, a large influx of migrant famers from Eastern China is being settled in this region to cultivate new agricultural lands that consumed even more water. Under those conditions, the natural riparian vegetation and the irrigation agriculture, especially along the lower reaches, suffers water shortage leading the degradation and economic losses, respectively. Along with the enlargement of irrigation area and periods of water shortage, soil salinization has become a major concern for farmers in the area. Alternative cash crops are much needed to reduce water use, so both native vegetation and human demand for water would be fulfilled. We hypothesized Apocynum Pictum, perennial herb species with multiple uses as potential substitute. Multidisciplinary approach is being used in this study to investigate three related issues to offer a basis for Apocynum's role in sustainable agriculture, such as Biomass production of Apocynum; Water budget of Apocynum; and Economic utilization of Apocynum. A.Pictum is perennial plant distributed in Central Asia and China, which its roots are perennial, while the stems die every year. Thus, A.pictum grow under the arid climate of Central Asia and provide utilization options without irrigation. We initially estimate water requirement for this plant is much less than cotton. In order to validate our hypothesis, we have measured water consumption of the

  4. Does migration benefit the schooling of children left behind?: Evidence from rural northwest China

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    Feng Hu

    2013-07-01

    Full Text Available BACKGROUND While many studies have found that migration can benefit home communities and family members left behind by increasing household income, thus easing liquidity constraints on investment; less is known about how "internal" migration and remittances affect the educational performance of the children who are left behind in the source communities. OBJECTIVE My aim in this paper is to examine the effects of migration on the educational attainment of left-behind rural children in northwest China. To gain a better understanding of whether the educational performance of these children improves or suffers when adult family members migrate, I attempt to disentangle the effects of remittances from the effects of migration. METHODS The data used in this study come from the 2004 wave of the Gansu Survey of Children and Families. To account for the possible endogeneity of migration-related variables, I use the migration network variables to instrument for different migration strategies. RESULTS The results show that the absence of adult household members, including parents, has a negative effect on the educational performance of the children left behind, but that remittances can partially compensate for this loss. Boys' educational performance does not seem to be greatly affected by the migration of adult household members. By contrast, the absence of adult household members is shown to have a large negative effect on girls' educational performance, and the positive effect of remittances is also found to be significant for girls. CONCLUSIONS The findings may be of interest to other developing countries with large internal migration flows and to the relevant policy makers, as the results suggest that remittances sent home by out-migrants may serve as a channel for investing in human capital in the migrants' regions of origin, and especially for investing in the human capital of girls.

  5. [Effects of mulching on soil moisture in a dryland winter wheat field, Northwest China].

    Science.gov (United States)

    Fan, Ying-Dan; Chai, Shou-Xi; Cheng, Hong-Bo; Chen, Yu-Zhang; Yang, Chang-Gang; Huang, Cai-Xia; Chang, Lei; Pang, Lei

    2013-11-01

    This paper studied the effects of different mulching modes on the soil moisture in a semi-arid rainfed area of Loess Plateau, Northwest China. Seven treatments were installed, i. e., mulching plastic film in summer (T1), mulching plastic film in autumn (T2), mulching 5 cm long wheat straw in summer (T3), mulching whole wheat straw in summer (T4), mulching plastic film in summer plus wheat straw (T5), mulching used plastic film after harvest (T6), and un-mulching (CK). In T6, the soil moisture in different layers at different crop growth stages was all higher than that in CK. In the other five mulching treatments, the soil moisture in 0-90 cm layer before flowering stage was obviously higher, but that in 0-90 cm layer after flowering stage and in 90-200 cm layer during the whole growth season was lower than that of CK. The soil moisture in 0-200 cm layer in T6 during the whole growth period was significantly higher than that in CK, with a difference of 0.9%, but the soil moisture in 0-200 cm layer in other mulching treatments was lower. As compared with plastic film mulching, straw mulching increased the soil moisture in 0-200 cm layer. The soil moisture under mulching with used plastic film after harvest was higher than that under mulching with new plastic film. As compared to CK, the grain yield of winter wheat with plastic film mulching was increased by 20.3%-29.0%, and that With straw mulching was increased by 5.0%-16.7%. There was a significant positive correlation between the crop productivity and the soil water consumption during the growth period (r = 0.77*).

  6. Halalkalicoccus paucihalophilus sp. nov., a halophilic archaeon from Lop Nur region in Xinjiang, northwest of China.

    Science.gov (United States)

    Liu, Bing-Bing; Tang, Shu-Kun; Zhang, Yong-Guang; Lu, Xin-Hua; Li, Li; Cheng, Juan; Zhang, Yuan-Ming; Zhang, Li-Li; Li, Wen-Jun

    2013-05-01

    Two extremely halophilic archaea, designated YIM 93701(T) and YIM 93664, were isolated from Lop Nur region in Xinjiang Province, northwest of China. The cells of the two strains were observed to be cocci, non-motile and Gram-negative. The organisms were determined to be aerobic and required at least 6 % NaCl for growth (optimum 20-25 % and maximum 35 %). Growth was found to occur in the ranges of 16-50 °C (optimum 37 °C) and pH 6.0-8.5 (optimum 6.5-7.5). Cells did not lyse in distilled water. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the two strains belongs to the genus Halalkalicoccus and possessed 99.3 and 99.5 % similarities with their closest phylogenetic relative Halalkalicoccus tibetensis JCM 11890(T). Major polar lipids of the two strains were determined to be phosphatidylglycerol(PG),phosphatidylglycerol phosphate methyl ester (PGP-Me), phosphatidylglycerol sulfate (PGS) and three unidentified glycolipids. The DNA G+C contents were determined to be 60.0-60.4 mol%. The DNA hybridization between the two strains was 92.0 %. In addition, the hybridizations of both strains to H. tibetensis were 49 and 52 %, respectively, and to Halalkalicoccus jeotali were 38 and 33 %, respectively. On the basis of physiological, biochemical tests and phylogenetic differentiations, strains YIM 93701(T) and YIM 93664 were classified as the same species which represent a novel species in the genus Halalkalicoccus, for which the name Halalkalicoccus paucihalophilus sp. nov. is proposed. The type strain is YIM 93701(T) (=JCM 17505(T) = CCTCC 2012803(T)).

  7. Nitrate Accumulation in Soil Profile of Dry Land Farming in Northwest China

    Institute of Scientific and Technical Information of China (English)

    FAN Jun; HAO Ming-De; SHAO Ming-An

    2003-01-01

    A long-term fertilizer experiment on dry land of the Loess Plateau, northwest China, has been conducted since 1984 to study the distribution and accumulation of NO3-N down to a depth of 400 cm in the profile of a coarse-textured dark loessial soil after continuous winter wheat cropping. Thirteen fertilizer treatments consisted of four levels of N and P applied alone or in combination. Annual N and P (P2O5) rates were 0,45, 90, 135 and 180 kg ha-1. After 15 successive cropping cycles, the soil samples were taken from each treatment for analysis of NO3-N concentration. The results showed that NO3-N distribution in the soil profile was quite different among the treatments. The application of fertilizer N alone resulted in higher NO3-N concentration in the soil profile than the combined application of N and P, showing that application of P could greatly reduce the NO3-N accumulation. With an annual application of 180 kg N ha-1 alone, a peak in NO3-N accumulation occurred at 140 cm soil depth, and the maximum NO3-N concentration in the soils was 67.92 mg kg-1. The amount of NO3-N accumulated in the soil profile decreased as the cumulative N uptake by the winter wheat increased. Application of a large amount of N resulted in lower N recoveries in winter wheat and greater NO3-N accumulation in soil profile. NO3-N did not enter underground water in the study region; therefore, there is no danger of underground water pollution. Amount of NO3-N accumulation can be predicted by an equation according to annual N and P rates based on the results of this experiment.

  8. Variation Characteristics of Regional Synchronous Wind in Hami, Xinjiang of Northwest China

    Institute of Scientific and Technical Information of China (English)

    黄林宏; 宋丽莉; 李刚; 辛渝

    2015-01-01

    From several towers in Hami, Xinjiang of Northwest China, built by the national wind power resources professional observation network, we selected three towers with synchronous 10-min average wind speed data for one year (May 2011–April 2012) under strict quality control. The towers are located where large-scale wind power development is projected. We analyzed the frequency and variation of extreme wind speed at low wind condition (LWC), rated wind condition (RWC), and cut-out wind condition (CWC), which may signifi cantly impact the electric power grid confi guration in large-scale wind power development. The correlation between duration and frequency of LWC/RWC/CWC is obtained. Major fi ndings are: 1) The frequency of CWC is the lowest among all conditions, its synchronous rate at all three towers tends to be zero, and the frequency of LWC is always greater than that of RWC. 2) Among the three towers, the synchronous rate of RWC steadily increases with height, and LWC diff ers little between diff erent levels. The synchronous rate of LWC concentrates in winter, while that of RWC mainly occurs in spring and summer. Diurnal variation of LWC/RWC during the entire year is signifi cantly diff erent. 3) During the study year, the longest durations of synchronous LWC and RWC among the three towers are up to 640 and 700 min, respectively. The duration and frequency of LWC/RWC can be quantitatively well described by a logarithmic function. Consequently, the synchronous rates of LWC and RWC over any duration in the region can be easily calculated by using the fi tting function equation from observed data. These results are of value to the planning of large-scale wind power transmission and grid dispatching in this area.

  9. Geochemical Responses to Anthropogenic and Natural Influences in Ebinur Lake Sediments of Arid Northwest China.

    Science.gov (United States)

    Ma, Long; Wu, Jinglu; Abuduwaili, Jilili; Liu, Wen

    2016-01-01

    Geochemical concentrations were extracted for a short sediment core from Ebinur Lake, located in arid northwest China, and mathematical methods were used to demonstrate the complex pattern of the geochemical anomalies resulting from the temporal changes in natural and anthropogenic forces on the lake sediments. The first element assemblage (C1) (aluminum, potassium, iron, magnesium, beryllium, etc.) was predominantly terrigenous; among the assemblage, total phosphorus and titanium were generally consistent with aluminum except with regards to their surface sequences, which inferred the differences of source regions for terrigenous detrital material led to this change around ca. 2000AD. The second assemblage (C2) (calcium and strontium) was found to have a negative relationship with aluminum through a cluster analysis. The third assemblage (C3) included sodium and magnesium, which were influenced by the underwater lake environment and deposited in the Ebinur depression. The concentration ratio of C1/(C1+C2) was used as an indicator for denudation amount of detrital materials, which was supported by the values of magnetic susceptibility. The enrichment factors for heavy metals suggested that the influence of human activities on heavy-metal enrichment in Ebinur Lake region was not severe over the past century. Prior to the 1960s, geochemical indicators suggested a stable lacustrine environment with higher water levels. Beginning in the 1960s, high agricultural water demand resulted in rapid declines in lake water level, with subsequent increases of lake water salinity, as evidenced by enhanced sodium concentration in lake core sediments. During this period, anthropogenic activity also enhanced the intensity of weathering and the denudation of the Ebinur watershed.

  10. Bayesian Network Modeling to Improve Water Pricing Practices in Northwest China

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    Yusuyunjiang Mamitimin

    2015-10-01

    Full Text Available Water pricing is regarded as the most important and simplest economic instrument to encourage more efficient use of irrigation water in crop production. In the extremely water-scarce Tarim River basin in northwest China, improving water use efficiency has high relevance for research and policy. A Bayesian network modeling approach was applied, which is especially suitable under data-scarce conditions and the complex geo-hydrological, socioeconomic, and institutional settings of the study region, as it allows the integration of data from various types of sources. The transdisciplinary approach aimed at understanding the actual water pricing practices, the shortcomings of the current system, and possible ways of improvement. In an iterative procedure of expert interviews and group workshops, the key factors related to water pricing and water use efficiency were identified. The interactions among specific factors were defined by the respective experts, generating a causal network, which describes all relevant aspects of the investigated system. This network was finally populated with probabilistic relationships through a second round of expert interviews and group discussions. The Bayesian modeling exercise was then conducted using Netica software. The modeling results show that the mere increase of water price does not lead to significant increases in water use efficiency in crop production. Additionally, the model suggests a shift to volumetric water pricing, subsidization of water saving irrigation technology, and advancing agricultural extension to enable the farmer to efficiently react to increased costs for water. The applied participatory modeling approach helped to stimulate communication among relevant stakeholders from different domains in the region, which is necessary to create mutual understanding and joint targeted action. Finally, the challenges related to the applied transdisciplinary Bayesian modeling approach are discussed in the

  11. Recent changes of precipitation in Gansu, Northwest China: An index-based analysis

    Science.gov (United States)

    Li, Cheng; Wang, Ranghui

    2017-07-01

    Monitoring variations in precipitation is important in detecting regional climate change and studying the hydrological cycle. An understanding of its dynamic characteristics will be valuable in the management of water resources in Northwest China. This study utilized daily precipitation data from 29 stations across Gansu spanning the years from 1960 to 2013; the data was used to investigate changes in precipitation by defining 21 precipitation-related indices. Trends were detected in the series of precipitation-related indices using the Mann-Kendall test. Primary results are as follows: (1) Decreasing trends in both the extreme precipitation and wet spell indices are indicative of a decrease in precipitation in southeastern Gansu, whereas the trends in the data indicate that northwestern Gansu has experienced an increase in precipitation; (2) decreasing trends in the annual number and length of dry spells with longer durations in northwestern Gansu also demonstrate that the precipitation frequency and intensity are increasing across this area; (3) by means of 24-month time scales, standardized precipitation index values, and principal component analysis, the Gansu can also be identified into two distinctive sub-regions, which predominantly show different variations of dryness/wetness during 1960-2013; and (4) the correlation analysis showed that the intensity of the western Pacific subtropical high possesses obvious effects on a number of precipitation indices in two subregions of Gansu. In addition, the Indian Ocean Dipole and Multivariate El Niño-Southern Oscillation (ENSO) index may also be important factors in the southeastern areas; in contrast, the impacts of large-scale climate indices on precipitation indices are less severe in northwestern Gansu.

  12. Recent changes of precipitation in Gansu, Northwest China: An index-based analysis

    Science.gov (United States)

    Li, Cheng; Wang, Ranghui

    2016-04-01

    Monitoring variations in precipitation is important in detecting regional climate change and studying the hydrological cycle. An understanding of its dynamic characteristics will be valuable in the management of water resources in Northwest China. This study utilized daily precipitation data from 29 stations across Gansu spanning the years from 1960 to 2013; the data was used to investigate changes in precipitation by defining 21 precipitation-related indices. Trends were detected in the series of precipitation-related indices using the Mann-Kendall test. Primary results are as follows: (1) Decreasing trends in both the extreme precipitation and wet spell indices are indicative of a decrease in precipitation in southeastern Gansu, whereas the trends in the data indicate that northwestern Gansu has experienced an increase in precipitation; (2) decreasing trends in the annual number and length of dry spells with longer durations in northwestern Gansu also demonstrate that the precipitation frequency and intensity are increasing across this area; (3) by means of 24-month time scales, standardized precipitation index values, and principal component analysis, the Gansu can also be identified into two distinctive sub-regions, which predominantly show different variations of dryness/wetness during 1960-2013; and (4) the correlation analysis showed that the intensity of the western Pacific subtropical high possesses obvious effects on a number of precipitation indices in two subregions of Gansu. In addition, the Indian Ocean Dipole and Multivariate El Niño-Southern Oscillation (ENSO) index may also be important factors in the southeastern areas; in contrast, the impacts of large-scale climate indices on precipitation indices are less severe in northwestern Gansu.

  13. Temporal-Spatial Pattern of Carbon Stocks in Forest Ecosystems in Shaanxi, Northwest China.

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    Gaoyang Cui

    Full Text Available The precise and accurate quantitative evaluation of the temporal and spatial pattern of carbon (C storage in forest ecosystems is critical for understanding the role of forests in the global terrestrial C cycle and is essential for formulating forest management policies to combat climate change. In this study, we examined the C dynamics of forest ecosystems in Shaanxi, northwest China, based on four forest inventories (1989-1993, 1994-1998, 1999-2003, and 2004-2008 and field-sampling measurements (2012. The results indicate that the total C storage of forest ecosystems in Shaanxi increased by approximately 29.3%, from 611.72 Tg in 1993 to 790.75 Tg in 2008, partially as a result of ecological restoration projects. The spatial pattern of C storage in forest ecosystems mainly exhibited a latitude-zonal distribution across the province, increasing from north (high latitude to south (low latitude generally, which signifies the effect of environmental conditions, chiefly water and heat related factors, on forest growth and C sequestration. In addition, different data sources and estimation methods had a significant effect on the results obtained, with the C stocks in 2008 being considerably overestimated (864.55 Tg and slightly underestimated (778.07 Tg when measured using the mean C density method and integrated method, respectively. Overall, our results demonstrated that the forest ecosystem in Shaanxi acted as a C sink over the last few decades. However, further studies should be carried out with a focus on adaption of plants to environmental factors along with forest management for vegetation restoration to maximize the C sequestration potential and to better cope with climate change.

  14. Temporal and spatial variations of precipitation in Northwest China during 1960-2013

    Science.gov (United States)

    Yang, Peng; Xia, Jun; Zhang, Yongyong; Hong, Si

    2017-01-01

    Based on the precipitation data from 96 weather stations in Northwest China (NWC) during 1960-2013, the Continuous Wavelet Transform (CWT) and the Mann-Kendall (MK) test were applied to analyze the precipitation spatiotemporal variations at different time scales. The relationships between the original precipitation and different periodic components were investigated. The results indicated that the annual precipitation was significantly increasing (P < 0.01) at the rate of 0.55 mm/a in the NWC. In terms of seasonal precipitation, the summer original precipitation significantly increased (P < 0.05) in the Southern Altay Mountain Basin (SAMB), Qaidam Basin (QB), Qiang Tang Plateau Basin (QTPB), Turpan-Hami Basin (THB), Tarim Desert Basin (TDB), Northern Tianshan Mountain Basin (NTMB) and NWC. For the winter original precipitation, except the Inner Mongolia Inland Rivers Basin and Northern Kunlun Mountain Basin, the significant increases (P < 0.05) were detected in the other sub-basins. In terms of monthly precipitation, significant increases were detected in January in the SAMB, NTMB and NWC, and July in the QB, Headstreams of Tarim River Basin (HTRB) and N. Additionally, most of the increasing and decreasing trends began in the mid-1980s or mid-1990s. Moreover, the periodic components were not always similar to the original data with the significant trends. The dominant scale of the original data from the periodic components was different in spatiotemporal distribution. Meanwhile, the relationship between the precipitation and El Niño-Southern Oscillation (ENSO) was different from period to period and from time scale to time scale. This study will help to develop better management measures to account for climate change and the supply/demand of water.

  15. Water resource management in river oases along the Tarim River in North-West of China

    Science.gov (United States)

    Kliucininkaite, Lina; Disse, Markus

    2013-04-01

    Tarim River is one of the longest inland rivers in the world. It flows its water in the northern part of the Taklamakan desert in Xinjiang, North-west of China, which is a very hostile region due its climatic conditions and particularly due to low precipitation and very high evaporation rates. During the past five decades intensive exploitation of water resources, mainly by agricultural activities, has changed the temporal and spatial distribution of them and caused serious environmental problems in the Tarim River Basin. The support measures for oasis management along the Tarim River under climatic and societal changes became the overarching goal of this research. The temperature has risen by nearly 1° C over the past 50 years in the Tarim River Basin so more water was available in the mountainous areas of Xinjiang, leading to an increasing trend of the headstream discharges of the Tarim Basin. Aksu, Hotan and Yarkant Rivers are three tributaries of the Tarim River, as well as its main water suppliers. However, under the condition of water increase with the volume of 25×108 m3 in headstreams in recent 10 years, the water to the mainstream has increased less than 108 m3 (in Alar hydrological station), which is less than 3% of the increased water volume of runoff. Moreover, the region is one of the biggest cotton and other cash crops producers in China. In addition, expansion of urban and, in particular, of irrigation areas have caused higher water consumption at different parts of the river, leading to severe ecological effects on rural areas, especially in the lower reaches. Moreover, it also highly affects groundwater level and quality. The aim of this research is to support decision makers, planners and engineers to find right measures in the area for the further development of the region, as well as adaptation to changing climate. Different scenarios for water resource management, as well as water distribution and allocation in a more efficient and water

  16. Molecular Epidemiological Investigation of Porcine kobuvirus and Its Coinfection Rate with PEDV and SaV in Northwest China

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    Chen Wang

    2016-01-01

    Full Text Available Porcine kobuvirus (PKV has circulated throughout China in recent years. Although many studies have detected it throughout the world, its molecular epidemiology has not been characterized in northwest China. To understand its prevalence, 203 fecal samples were collected from different regions of Gansu Province and tested with reverse transcription-polymerase chain reaction. In this study, we tested these samples for PKV, porcine epidemic diarrhea virus (PEDV, and sapovirus and analyzed the amplified 2C gene fragments of PKV. Overall, 126 (62.1% samples were positive for PKV. Of the 74 piglets samples among the 203 fecal samples, 65 (87.8% were positive for PKV. PKV infection was often accompanied by PEDV, but the relationship between the two viruses must be confirmed. A phylogenetic analysis indicated that the PKV strains isolated from the same regions clustered on the same branches. This investigation shows that PKV infections are highly prevalent in pigs in northwest China, especially in piglets with symptoms of diarrhea.

  17. Trend Patterns of Vegetative Coverage and Their Underlying Causes in the Deserts of Northwest China over 1982-2008.

    Science.gov (United States)

    Zhang, Tianyi; Wang, Hesong

    2015-01-01

    We identified the spatiotemporal patterns of the Normalized Difference Vegetation Index (NDVI) for the years 1982-2008 in the desert areas of Northwest China and quantified the impacts of climate and non-climate factors on NDVI changes. The results indicate that although the mean NDVI has improved in 24.7% of the study region; 16.3% among the region has been stagnating in recent years and only 8.4% had a significantly increasing trend. Additionally, 45.3% of the region has maintained a stable trend over the study period and 30.0% has declined. A multiple regression model suggests that a wetter climate (quantified by the Palmer Drought Severity Index, PDSI) is associated with higher NDVI in most areas (18.1% of significance) but these historical changes in PDSI only caused an average improvement of approximately 0.4% over the study region. Contrasting the regression results under different trend patterns, no significant differences in PDSI impacts were detected among the four trend patterns. Therefore, we conclude that climate is not the primary driver for vegetative coverage in Northwest China. Future studies will be required to identify the impacts of specific non-climatic factors on vegetative coverage based on high-resolution data, which will be beneficial in creating an effective strategy to combat the recent desertification trend in China.

  18. Sources and characteristics of organochlorine pesticides in the soil and sediment along the Kaidu-Peacock River, Northwest of China

    Science.gov (United States)

    Chen, Wei; Qi, Shihua; Peng, Fei; Qu, Chengkai; Zhang, Yuan; Xing, Xinli; Zhang, Jiaquan

    2016-04-01

    Organochlorine pesticides (OCPs) are a sub-group of persistent organic pollutants (POPs), which have raised the concerns from researchers all around the world for several decades. But very little research has been conducted on POPs in the arid zone of Northwest China. More than 100 soil and sediment samples were collected from Kaidu-Peacock River of Xinjiang, Northwest of China, to investigate the organochlorine pesticides (OCPs) in this region analysed by the gas chromatograph equipped with a mass selective detector (GC-MSD). Our pre-study in 2006 (Chen et al. 2011) in the same region, showed that OCPs except o,p'-DDT were detected in sediments from the Peacock River. Similar results were found in the whole river catchment in this investigation. DDTs, HCHs, chlordanes and endosulfans were the dominant OCPs residual in the soil and sediments. This study confirmed that POPs, such as OCPs in this region were contributed to by both local emissions and long-term atmospheric transport and may pose risks to human health and the ecosystem. Chen, W., Jing, M., Bu, J., Ellis Burnet, J., Qi, S., Song, Q., Ke, Y., Miao, J., Liu, M. & Yang, C. (2011) Organochlorine pesticides in the surface water and sediments from the Peacock River Drainage Basin in Xinjiang, China: a study of an arid zone in Central Asia. Environmental Monitoring and Assessment, 177, 1-21.

  19. Global Warming: The Instability of Desert Climate is Enhancing in the Northwest Area in China: A Case Study in the Desert Area in Northwestern China

    Directory of Open Access Journals (Sweden)

    Zhao-Feng Chang

    2013-03-01

    Full Text Available To disclose the relation between the sandstorms change and the temperature changes, a case study in the desert area in northwestern china is investigated. The results showed that: the instability of climate in Minqin desert area is enhancing in the arid desert region in northwest China. Mainly as follows: Variation the annual extreme maximum temperature increasing. Variation of extreme minimum temperature also an increasing trend. Average visibility of sandstorms significantly reduced and the fluctuation trend increased significantly. In the past two years, there have been some unusual climate events in other regions in China. They reflect the fact that the deterioration of the stability of the climate change. The instability of the climate change impact on human life and production is increased more than global warming, more worthy of global concern.

  20. Poverty and Proximate Barriers to Learning: Vision Deficiencies, Vision Correction and Educational Outcomes in Rural Northwest China.

    Science.gov (United States)

    Hannum, Emily; Zhang, Yuping

    2012-09-01

    Uncorrected vision may present a significant barrier to educational mobility in poor communities in low and middle income countries. Focusing on the case of rural Northwest China, we analyze the Gansu Survey of Children and Families (2,000 children; 100 rural villages) and the Gansu Vision Intervention Project (a randomized trial; 19,185 students, 165 schools, two counties). Four main findings emerge: significant unmet need for vision correction; socioeconomic gradients in vision correction; somewhat greater vulnerability to vision problems among higher socioeconomic status and more academically engaged children; and significant favorable effects of vision correction on math and literacy performance and class failure.

  1. [Mechanisms of grass in slope erosion control in Loess sandy soil region of Northwest China].

    Science.gov (United States)

    Zhao, Chun-Hong; Gao, Jian-En; Xu, Zhen

    2013-01-01

    By adopting the method of simulated precipitation and from the viewpoint of slope hydrodynamics, in combining with the analysis of soil resistance to erosion, a quantitative study was made on the mechanisms of grass in controlling the slope erosion in the cross area of wind-water erosion in Loess Plateau of Northwest China under different combinations of rainfall intensity and slope gradient, aimed to provide basis to reveal the mechanisms of vegetation in controlling soil erosion and to select appropriate vegetation for the soil and water conservation in Loess Plateau. The grass Astragalus adsurgens with the coverage about 40% could effectively control the slope erosion. This grass had an efficiency of more than 70% in reducing sediment, and the grass root had a greater effect than grass canopy. On bare slope and on the slopes with the grass plant or only the grass root playing effect, there existed a functional relation between the flow velocity on the slopes and the rainfall intensity and slope gradient (V = DJ(0.33 i 0.5), where V is flow velocity, D is the comprehensive coefficient which varies with different underlying surfaces, i is rainfall intensity, and J is slope gradient). Both the grass root and the grass canopy could markedly decrease the flow velocity on the slopes, and increase the slope resistance, but the effect of grass root in decreasing flow velocity was greater while the effect in increasing resistance was smaller than that of grass canopy. The effect of grass root in increasing slope resistance was mainly achieved by increasing the sediment grain resistance, while the effect of canopy was mainly achieved by increasing the slope form resistance and wave resistance. The evaluation of the soil resistance to erosion by using a conceptual model of sediment generation by overland flow indicated that the critical shear stress value of bare slope and of the slopes with the grass plant or only the grass root playing effect was 0.533, 1.672 and 0

  2. Biophysical controls on net ecosystem CO2 exchange over a semiarid shrubland in northwest China

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    X. Jia

    2014-03-01

    Full Text Available The carbon (C cycling in semiarid and arid areas remains largely unexplored, despite the wide distribution of drylands globally. Rehabilitation practices have been carried out in many desertified areas, but information on the C sequestration potential of recovering vegetation is still largely lacking. Using the eddy-covariance technique, we measured the net ecosystem CO2 exchange (NEE over a recovering shrub ecosystem in northwest China throughout 2012 in order to (1 quantify NEE and its components, (2 examine the dependence of C fluxes on biophysical factors at multiple timescales. The annual budget showed a gross ecosystem productivity (GEP of 456 ± 8 g C m−2 yr−1 and an ecosystem respiration (Re of 379 ± 3 g C m−2 yr−1, resulting in a net C sink of 77 ± 7 g C m−2 yr−1. The maximum daily NEE, GEP and Re were −4.7, 6.8 and 3.3 g C m−2 day−1, respectively. Both the maximum C assimilation rate (i.e., at optimum light intensity and the quantum yield varied strongly over the growing season, being higher in summer and lower in spring and autumn. At the half-hourly scale, water stress exerted a major control over daytime NEE, and interacted with heat stress and photoinhibition in constraining C fixation by the vegetation. Low soil moisture also reduced the temperature sensitivity of Re (Q10. At the synoptic scale, rain events triggered immediate pulses of C release from the ecosystem, followed by peaks of CO2 uptake 1–2 days later. Over the entire growing season, leaf area index accounted for 45 and 65% of the seasonal variation in NEE and GEP, respectively. There was a linear dependence of daily Re on GEP, with a slope of 0.34. These results highlight the role of abiotic stresses and their alleviation in regulating C cycling in the face of an increasing frequency and intensity of extreme climatic events.

  3. Source apportionment of carbonaceous aerosols in a megacity of northwest China: insights from radiocarbon measurement

    Science.gov (United States)

    Ni, Haiyan; Huang, Rujin; Dusek, Ulrike

    2017-04-01

    Fine particulate matter (PM2.5) samples were collected from 5 July 2008 to 27 June 2009 at Xi'an, a very polluted megacity in Northwest China. The 24 h averaged PM2.5concentrations (ranged from 32 μg m-3 to 339 μg m-3) were 1-14 times higher than the WHO guideline for 24 h PM2.5(25 μg m-3). In this work, we unambiguously quantify fossil (e.g., vehicle emissions, coal burning etc.) and non-fossil (e.g., biomass burning, cooking, biogenic emissions etc.) contributions to organic carbon (OC) and elemental carbon (EC) of PM2.5using radiocarbon (14C) measurement. In addition, we measured PM2.5 major components and source markers, including OC and EC, ions, trace elements, polycyclic aromatic hydrocarbons (PAHs), oxygenated PAHs (o-PAHs), anhydrous sugars and hopanes. The preliminary results of radiocarbon measurements in OC and EC show that the annual mean contributions from fossil-fuel combustion to EC was 76 ± 8% (6 ± 2 μg m-3). The remaining 24 ± 8% (2 ± 1 μg m-3) was attributed to biomass burning, with higher contribution in the cold period (˜33%) compared to the warm period (˜21%), due to enhanced emissions from local biomass burning activities in winter. In contrast with EC, OC was dominated by non-fossil sources, with an annual average of 54 ± 8 % (13 ± 10 μg m-3). Clear seasonal variations were seen in OC concentrations both from fossil fuel (OCff), and from non-fossil sources (OCnf), with maxima in the cold period and minima in the warm period, because of enhanced fossil and non-fossil activities in winter, mainly biomass burning and domestic coal burning. Further source apportionment of OC, including primary/secondary fossil OC, primary/secondary non-fossil OC, will be conducted by combining 14C results with positive matrix factorization (PMF) analysis of organic matter (OM).

  4. Prevalence and associated factors of corneal blindness in Ningxia in northwest China

    Directory of Open Access Journals (Sweden)

    Xun-Lun Sheng

    2014-06-01

    Full Text Available AIM:To describe the prevalence and demographic characteristics of corneal blindness in an urban and rural region of Ningxia, located in the northwest part of China.METHODS:A stratified, randomized sampling procedure was employed in the study, including urban and rural area of all age group. Visual acuity, anterior segment and ocular fundus were checked. Related factor of corneal disease, including age, gender, education status, ethnic group, location and occupation, were identified according to uniform customized protocol. An eye was defined to be corneal blindness if the visual acuity was <20/400 due to a corneal disease.RESULTS:Three thousand individuals (1290 from urban area and 1710 from rural area participated in the investigation, with a response rate of 80.380%. The prevalence of corneal blindness was 0.023% in both eyes and 0.733% in at least one eye. The blindness in at least one eye with varied causes was present in 106 participants (3.533% and in bilateral eyes in 34 participants (1.133%. The corneal diseases accounted for 20.754% of blindness in at least one eye and 20.588% of bilateral blindness. The prevalence of corneal disease was higher in older and Han ethnic group, especially those who occupied in agriculture and outdoor work. People with corneal blindness were more likely to be older and lower education. Rural population were more likely to suffer from bilateral corneal blindness than the urban population in ≥59-year group (χ2=6.716, P=0.019. Infectious, trauma and immune corneal disease were the three leading causes of corneal disease. Trauma corneal disease was more likely leading to blindness in one eye. However, infectious and immune corneal diseases make more contribution to the bilateral corneal blindness.CONCLUSION: Corneal blindness is a significant burden of in Ningxia population, encompassing a variety of corneal infections and trauma; the majority of those were avoidable. Health promotion strategies and good

  5. Numerical Simulation of the Effects of Grassland Degradation on the Surface Climate in Overgrazing Area of Northwest China

    Directory of Open Access Journals (Sweden)

    Yanfei Li

    2013-01-01

    Full Text Available The climatic effects of LUCC have been a focus of current researches on global climate change. The objective of this study is to investigate climatic effects of grassland degradation in Northwest China. Based on the stimulation of the conversion from grassland to other land use types during the next 30 years, the potential effects of grassland degradation on regional climate in the overgrazing area of Northwest China from 2010 to 2040 have been explored with Weather Research and Forecasting model (WRF. The analysis results show that grassland will mainly convert into barren land, croplands, and urban land, which accounts for 42%, 48%, and 10% of the total converted grassland area, respectively. The simulation results indicate that the WRF model is appropriate for the simulation of the impact of grassland degradation on climate change. The grassland degradation during the next 30 years will result in the decrease of latent heat flux, which will further lead to the increase of temperature in summer, with an increment of 0.4–1.2°C, and the decrease of temperature in winter, with a decrement of 0.2°C. In addition, grassland degradation will cause the decrease of precipitation in both summer and winter, with a decrement of 4–20 mm.

  6. Seroprevalence and risk factors associated with hepatitis E virus infection in three species of pet birds in northwest China.

    Science.gov (United States)

    Cong, Wei; Meng, Qing-Feng; Shan, Xiao-Feng; Sun, Wu-Wen; Qin, Si-Yuan; Zhang, Xiao-Xuan; Huang, Si-Yang; Qian, Ai-Dong

    2014-01-01

    Hepatitis E virus (HEV), the causative agent of hepatitis E, has been reported in a wide variety of animals, including birds, but little is known of HEV infection in pet birds in northwest China. The objective of the present investigation was to examine HEV seroprevalence in three species of pet birds, namely, Eurasian siskin, Oriental skylark, and black-tailed grosbeak from Gansu. Serum samples collected from 685 pet birds from August 2011 to September 2012 were examined independently for the presence of antibodies against HEV. A total of 59 (8.31%) pet birds were tested positive for HEV antibodies by the commercially available enzyme immunoassay kits. Of these, the seroprevalence was diverse in different species pet birds; the most frequent level was 10.83% (39/360) in Eurasian siskin, followed by 6.57% (19/289) in Oriental skylark, and 2.29% (1/36) in black-tailed grosbeak. Age and collecting region of pet birds were the main risk factors associated with HEV infection. The present study firstly revealed the seroprevalence of HEV infection in three species of pet birds in northwest China, which provided the baseline data for taking comprehensive countermeasures and measures for effectively preventing and controlling HEV infection in birds.

  7. Analysis of characteristics of multiple time scale drought based on SPEI in the east of northwest China

    Science.gov (United States)

    Wang, Zhilan; Li, Yaohui; Wang, Suping

    2017-04-01

    From characteristics of multiple time scale of drought, the Standardized Precipitation Evaportranspiration Index (SPEI) considering precipitation and temperature are calculated using CRU update data, and the characteristics of drought at different time scales from 1901 to 2012 in the east of northwest China have been investigated. In this paper, reliability for hundred years of the CRU data has been tested, and the adaptability of SPEI in study area has been discussed. The result shows that, the SPEI is confirmed to be applicable to analyze the drought in the east of northwest China from drought intensity and range. The time scale of SPEI is shorter, the fluctuation is more frequent, and the change is more significantly. The amplitude, period and phase of SPEI curve with different time scales are not the same. Short time scale mainly shows seasonal characteristics, and long time scale shows interannual and decadal characteristics. The study area is divided into the eastern of the Plateau area and the southern of Shaanxi area. There are three times extreme drought events in 48 months time scale of the SPEI index of less than -2.0 in the eastern of the Plateau area from 1901 to 2012, and only one time in the southern of Shaanxi area. Finally, the contribution of temperature anomaly to the drought is analyzed. The result indicates that high temperature contribution cannot be neglected by comparison with the SPI index.

  8. Chemical, Mechanical, and Durability Properties of Concrete with Local Mineral Admixtures under Sulfate Environment in Northwest China

    Directory of Open Access Journals (Sweden)

    Qingke Nie

    2014-05-01

    Full Text Available Over the vast Northwest China, arid desert contains high concentrations of sulfate, chloride, and other chemicals in the ground water, which poses serious challenges to infrastructure construction that routinely utilizes portland cement concrete. Rapid industrialization in the region has been generating huge amounts of mineral admixtures, such as fly ash and slags from energy and metallurgical industries. These industrial by-products would turn into waste materials if not utilized in time. The present study evaluated the suitability of utilizing local mineral admixtures in significant quantities for producing quality concrete mixtures that can withstand the harsh chemical environment without compromising the essential mechanical properties. Comprehensive chemical, mechanical, and durability tests were conducted in the laboratory to characterize the properties of the local cementitious mineral admixtures, cement mortar and portland cement concrete mixtures containing these admixtures. The results from this study indicated that the sulfate resistance of concrete was effectively improved by adding local class F fly ash and slag, or by applying sulfate resistance cement to the mixtures. It is noteworthy that concrete containing local mineral admixtures exhibited much lower permeability (in terms of chloride ion penetration than ordinary portland cement concrete while retaining the same mechanical properties; whereas concrete mixtures made with sulfate resistance cement had significantly reduced strength and much increased chloride penetration comparing to the other mixtures. Hence, the use of local mineral admixtures in Northwest China in concrete mixtures would be beneficial to the performance of concrete, as well as to the protection of environment.

  9. Spatial distribution of soil organic carbon and its influencing factors in desert grasslands of the Hexi Corridor, northwest China.

    Science.gov (United States)

    Wang, Min; Su, Yongzhong; Yang, Xiao

    2014-01-01

    Knowledge of the distribution patterns of soil organic carbon (SOC) and factors that influence these patterns is crucial for understanding the carbon cycle. The objectives of this study were to determine the spatial distribution pattern of soil organic carbon density (SOCD) and the controlling factors in arid desert grasslands of northwest China. The above- and belowground biomass and SOCD in 260 soil profiles from 52 sites over 2.7×10(4) km2 were investigated. Combined with a satellite-based dataset of an enhanced vegetation index during 2011-2012 and climatic factors at different sites, the relationships between SOCD and biotic and abiotic factors were identified. The results indicated that the mean SOCD was 1.20 (SD:+/- 0.85), 1.73 (SD:+/- 1.20), and 2.69 (SD:+/- 1.91) kg m(-2) at soil depths of 0-30 cm, 0-50 cm, and 0-100 cm, respectively, which was smaller than other estimates in temperate grassland, steppe, and desert-grassland ecosystems. The spatial distribution of SOCD gradually decreased from the southeast to the northwest, corresponding to the precipitation gradient. SOCD increased significantly with vegetation biomass, annual precipitation, soil moisture, clay and silt content, and decreased with mean annual temperature and sand content. The correlation between BGB and SOCD was closer than the correlation between AGB and SOCD. Variables could together explain about 69.8%, 74.4%, and 78.9% of total variation in SOCD at 0-30 cm, 0-50 cm, and 0-100 cm, respectively. In addition, we found that mean annual temperature is more important than other abiotic factors in determining SOCD in arid desert grasslands in our study area. The information obtained in this study provides a basis for accurately estimating SOC stocks and assessing carbon (C) sequestration potential in the desert grasslands of northwest China.

  10. SHRIMP U-Pb Zircon Dating of the Tula Granite Pluton on the South Side of the Altun Fault and Its Geological Implications

    Institute of Scientific and Technical Information of China (English)

    WU Suoping; WU Cailai; WANG Meiying; CHEN Qilong; Joseph L. WOODEN

    2008-01-01

    The Tula A2-subtype granite pluton is located between the Altun fault and its branching fault.According to the geological, geochemical, REE and trace elements characteristics, it belongs to the A2 (PA) subtype granite. The SHRIMP U-Pb zircon dating gives a result of 385.2+8.1 Ma, which is located between the Middle and Late Devonian in the international stratigraphic chart, and can be regarded as the crystallization age of the Tula granite. The study indicates that the Tula area was in a local extensional environment in the end of the Middle Devonian, and that environment was probably related to the synchronized strike-slip activity of the Altun fault.

  11. How to help woody plants to overcome drought stress?-a control study of four tree species in Northwest China.

    Science.gov (United States)

    Liu, Xiaozhen; Zhang, Shuoxin

    2010-05-01

    Water is essential for plants and involves most physical and chemical processes within their lifecycles. Drought stress is a crucial limiting factor for plant growth and production. 48% of the land in China is arid and semi-arid, and non-irrigated land occupies approximately 51.9% of the total cultivated areas. Therefore, studies on plant drought resistant mechanisms have great significance for improving water use efficiency and thus increasing productivity of economical plants. Prior research has shown that the application of nitrogenous fertilizer affects the drought-resistant characteristics of plants. This study aimed to reveal the effect of nitrogenous fertilizer on physiological aspects and its impact on the drought resistance of four tree species (Robinia pseudoacacia L., Ligustrum lucidum Ait., Acer truncatum Bge. and Ulmus pumila L. ) in northwest China. Three levels of nitrogen fertilization (46% N based of urea adjusted to: 5g/15g soil, 15g/15g soil and 25g/15g soil) and an additional control study were applied to 2-year-old well-grown seedlings under drought conditions (30% field moisture capacity). Stomatal conductance, transpiration rate and net photosynthetic rate were measured by a LI-6400 photosynthesis system, while water use efficiency was calculated from net photosynthesis rate and transpiration rate. The results revealed that as the amount of urea applied was raised, stomatal conductance, transpiration rate and net photosynthetic rate decreased significantly, and thus water use efficiency significantly increased. It is therefore concluded that the application of nitrogenous fertilizer regulated physiological parameters by reducing stomata conductance to improve water use efficiency. In addition, among the four tree species, U. pumila had the maximum value of water use efficiency under the same drought condition. The outcome of this study provides a guided option for forest management in arid and semi-arid areas of northwest China.

  12. Application of Mulching Materials of Rainfall Harvesting System for Improving Soil Water and Corn Growth in Northwest of China

    Institute of Scientific and Technical Information of China (English)

    HAN Juan; JIA Zhi-kuan; HAN Qing-fang; ZHANG Jie

    2013-01-01

    The ridge and furrow rainfall harvesting (RFRH) system is used for dryland crop production in northwest of China. To determine the effects of RFRH using different mulching materials on corn growth and water use efifciency (WUE), a ifeld experiment was conducted during 2008-2010 at the Heyang Dryland Experimental Station, China. Four treatments were used in the study. Furrows received uncovered mulching in all RFRH treatments whereas ridges were mulched with plastic iflm (PF), biodegradable iflm (BF) or liquid iflm (LF). A conventional lfat ifeld without mulching was used as the control (CK). The results indicated that the average soil water storage at depths of 0-200 cm were 8.2 and 7.3%, respectively higher with PF and BF than with CK. However, LF improved soil water storage during the early growth stage of the crop. Compared with CK, the corn yields with PF and BF were increased by 20.4 and 19.4%, respectively, and WUE with each treatment increased by 23.3 and 21.7%, respectively. There were no signiifcant differences in corn yield or WUE with the PF and BF treatments. The net income was the highest with PF, followed by BF, and the 3-yr average net incomes with these treatments were increased by 2 559 and 2 430 CNY ha-1, respectively, compared with CK. BF and PF had similar effects in enhancing the soil water content, crop yield and net income. Therefore, it can be concluded that biodegradable iflm may be a sustainable ecological alternative to plastic iflm for use in the RFRH system in northwest of China.

  13. Identification of soil heavy metal sources and improvement in spatial mapping based on soil spectral information: A case study in northwest China

    NARCIS (Netherlands)

    Chen, Tao; Chang, Qingrui; Liu, Jing; Clevers, J.G.P.W.; Kooistra, L.

    2016-01-01

    In a sewage irrigation area of northwest China, 52 topsoil samples were collected to measure the contents of arsenic (As), chromium (Cr), copper (Cu), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn). To identify their sources, multivariate statistics and geostatistics were appl

  14. Transcending an Urban-Rural Divide: Rural Youth's Resistance to Townization and Schooling, a Case Study of a Middle School in Northwest China

    Science.gov (United States)

    Lou, Jingjing

    2011-01-01

    Based on an ethnographic study in a rural middle school in Northwest China, the author explores how the transition of the rural countryside, specifically townization, has challenged the urban-rural dichotomy being reproduced in and by formal schooling. Rural students express criticism of the chaos, pollution, and corruption they have experienced…

  15. Identification of soil heavy metal sources and improvement in spatial mapping based on soil spectral information: A case study in northwest China

    NARCIS (Netherlands)

    Chen, Tao; Chang, Qingrui; Liu, Jing; Clevers, J.G.P.W.; Kooistra, L.

    2016-01-01

    In a sewage irrigation area of northwest China, 52 topsoil samples were collected to measure the contents of arsenic (As), chromium (Cr), copper (Cu), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn). To identify their sources, multivariate statistics and geostatistics were

  16. Characterizing dust aerosols in the atmospheric boundary layer over the deserts in Northwest China: monitoring network and field observation

    Science.gov (United States)

    He, Q.; Matimin, A.; Yang, X.

    2016-12-01

    TheTaklimakan, Gurbantunggut and BadainJaran Deserts with the total area of 43.8×104 km2 in Northwest China are the major dust emission sources in Central Asia. Understanding Central Asian dust emissions and the interaction with the atmospheric boundary layer has an important implication for regional and global climate and environment changes. In order to explore these scientific issues, a monitoring network of 63 sites was established over the vast deserts (Taklimakan Desert, Gurbantunggut Desert and Badain Jaran Desert) in Northwest China for the comprehensive measurements of dust aerosol emission, transport and deposition as well as the atmospheric boundary layer including the meteorological parameters of boundary layer, surface radiation, surface heat fluxes, soil parameters, dust aerosol properties, water vapor profiles, and dust emission. Based on the monitoring network, the field experiments have been conducted to characterize dust aerosols and the atmospheric boundary layer over the deserts. The experiment observation indicated that depth of the convective boundary layer can reach 5000m on summer afternoons. In desert regions, the diurnal mean net radiation was effected significantly by dust weather, and sensible heat was much greater than latent heat accounting about 40-50% in the heat balance of desert. The surface soil and dust size distributions of Northwest China Deserts were obtained through widely collecting samples, results showed that the dominant dust particle size was PM100within 80m height, on average accounting for 60-80% of the samples, with 0.9-2.5% for PM0-2.5, 3.5-7.0% for PM0-10 and 5.0-14.0% for PM0-20. The time dust emission of Taklimakan Desert, Gurbantunggut Desert and Badain Jaran Desert accounted for 0.48%, 7.3%×10-5and 1.9% of the total time within a year, and the threshold friction velocity for dust emission were 0.22-1.06m/s, 0.29-1.5m/s and 0.21-0.59m/s, respectively.

  17. Land Use Changes of an Aeolian-Loessial Soil Area in Northwest China: Implications for Ecological Restoration

    Institute of Scientific and Technical Information of China (English)

    CHEN Yu-Fu; LIU Yan-Sui; WANG Jing; YAN Jian-Ping; GUO Xu-Dong

    2009-01-01

    China has experienced dramatic land use changes over recent decades,with marked environmental and socio-economic consequences.Hcngshan County,located in the aeolian-loessial area of Northwest China,was investigated to illustrate land use changes and their implications for environmental and long-term rural economic development.The farmland in Hengshan County significantly decreased during 1990-2003,whereas forest land and grassland increased.The conversion rates of farmland,orchard land,forest land and construction land varied markedly among different periods:1990-1995,1995-2000 and 2000-2003.Conversion of orchard land,grassland and construction land was dominant in 1990-1995,whereas the conversion of farmland to forest land mainly occurred in 2000-2003.The results suggested a profound transition in institutional policy and political economy of land management,including implementation of integrated soil erosion control projects,adoption of a market-oriented economy and the 'Grain-for-Green' policy,during this period in China.To achieve long-term sustainable land use in Hengshan County,efforts should aim at increasing off-farm income of rural families as well as establishing land-economizing mechanisms to promote land productivity,in addition to conservation measures.

  18. Plant species diversity of wetland ecosystem in an arid and semi-arid region in northwest China

    Institute of Scientific and Technical Information of China (English)

    LI Rui; LIU Yunfang; ZHANG Kebin

    2007-01-01

    In order to study the changes of plant species diversity along the biotope gradient and its influencing factors in a wetland-add grassland ecosystem in the add and semi-arid regions of northwest China,four transect lines were set along the biotope gradient in four directions:east,northeast,west and northwest,and altogether 123 sample plots were investigated on species composition,density,foliage cover,height and biomass (calculated in fresh weight).The whole study area was divided into the Wetland zone,the ecotone and the arid grassland zone in terms of habitat characteristics and vegetation types.In this paper,we analyzed and compared the species diversity in the ecotone of a wetland-dry grassland ecosystem in Yanchi County,Ningxia Hui Autonomous Region,with the help of biodiversity software BioDiversity Pro and statistical software Microcal Origin,as well as the combined measurement of species diversity indices.The results revealed distinct differences between those three vegetation zones along each transect line.The ecotone had the highest richness indices (R) and comprehensive diversity indices (Y),reflecting the edge effect.The greatest evenness indices (E) were found in the add grassland zones.This result agreed with the phenomenon of desertification reversion,vegetation restoration and dominant communities' formation.As for the four transect lines,the east and the northeast scored higher in each diversity index than the others due to less human disturbance,gentler topography uplift and more intercepted materials and energies.The highest Simpson index value was found in the northeast transect line,which was 39.9% higher than the lowest in the Northwest.

  19. Evaluation of the tourism climate in the Hexi Corridor of northwest China's Gansu Province during 1980-2012

    Science.gov (United States)

    Zhang, Fuxian; Zhang, Mingjun; Wang, Shengjie; Qiang, Fang; Che, Yanjun; Wang, Jie

    2017-08-01

    As a pivotal section of the Silk Road in northwest China, the Hexi Corridor is a popular tourist destination. In this study, the tourism climate conditions in this region were discussed using the Physiologically Equivalent Temperature (PET) and the Climate-Tourism/Transfer-information-Scheme (CTIS) from 1980 to 2012. Overall, cold or cool stress was prevalent in the area, and the optimal travel period was from May to September. With global warming, the annual numbers of cumulative days with relatively cold conditions decreased, and the annual numbers of cumulative days with comfortable and relatively hot conditions increased. Two typical stations, Wushaoling and Dunhuang, were compared and analysed for their tourism climate information according to the frequency of PET and CTIS conditions, respectively. In addition, regional variations in the tourism climate conditions based on geographic information systems (GIS) were investigated during the optimal travel period.

  20. Evaluation of the tourism climate in the Hexi Corridor of northwest China's Gansu Province during 1980-2012

    Science.gov (United States)

    Zhang, Fuxian; Zhang, Mingjun; Wang, Shengjie; Qiang, Fang; Che, Yanjun; Wang, Jie

    2016-05-01

    As a pivotal section of the Silk Road in northwest China, the Hexi Corridor is a popular tourist destination. In this study, the tourism climate conditions in this region were discussed using the Physiologically Equivalent Temperature (PET) and the Climate-Tourism/Transfer-information-Scheme (CTIS) from 1980 to 2012. Overall, cold or cool stress was prevalent in the area, and the optimal travel period was from May to September. With global warming, the annual numbers of cumulative days with relatively cold conditions decreased, and the annual numbers of cumulative days with comfortable and relatively hot conditions increased. Two typical stations, Wushaoling and Dunhuang, were compared and analysed for their tourism climate information according to the frequency of PET and CTIS conditions, respectively. In addition, regional variations in the tourism climate conditions based on geographic information systems (GIS) were investigated during the optimal travel period.

  1. Age Structure and Growth of Degraded Populus euphratica Floodplain Forests in North-west China and Perspectives for Their Recovery

    Institute of Scientific and Technical Information of China (English)

    Janneke Westermann; Stefan Zerbe; Dieter Eckstein

    2008-01-01

    The Populus euphratica floodplain forests along the lower reaches of the Tarim River in continental-arid Xinjiang (north-west China) have been declining in recent decades as a result of dam constructions and the withdrawal of water from the river. Since 2000, controlled flooding has been carried out to counteract this process of degradation. However, the consequences of a changing water regime for the floodplain ecosystem are not yet sufficiently investigated. In 2004 we sampled a total of 150 P. euphratica trees along two transects at the middle and lower reaches of the Tarim River to compare the age structure and growth of these two tree populations. The anthropogenic drawdown of the groundwater table had no effect on the average growth of the trees at the lower reaches. However, tree growth abruptly increased after controlled flooding, thus showing distinct signs of recovery.

  2. Simulating Crop Evapotranspiration Response under Different Planting Scenarios by Modified SWAT Model in an Irrigation District, Northwest China.

    Directory of Open Access Journals (Sweden)

    Xin Liu

    Full Text Available Modelling crop evapotranspiration (ET response to different planting scenarios in an irrigation district plays a significant role in optimizing crop planting patterns, resolving agricultural water scarcity and facilitating the sustainable use of water resources. In this study, the SWAT model was improved by transforming the evapotranspiration module. Then, the improved model was applied in Qingyuan Irrigation District of northwest China as a case study. Land use, soil, meteorology, irrigation scheduling and crop coefficient were considered as input data, and the irrigation district was divided into subdivisions based on the DEM and local canal systems. On the basis of model calibration and verification, the improved model showed better simulation efficiency than did the original model. Therefore, the improved model was used to simulate the crop evapotranspiration response under different planting scenarios in the irrigation district. Results indicated that crop evapotranspiration decreased by 2.94% and 6.01% under the scenarios of reducing the planting proportion of spring wheat (scenario 1 and summer maize (scenario 2 by keeping the total cultivated area unchanged. However, the total net output values presented an opposite trend under different scenarios. The values decreased by 3.28% under scenario 1, while it increased by 7.79% under scenario 2, compared with the current situation. This study presents a novel method to estimate crop evapotranspiration response under different planting scenarios using the SWAT model, and makes recommendations for strategic agricultural water management planning for the rational utilization of water resources and development of local economy by studying the impact of planting scenario changes on crop evapotranspiration and output values in the irrigation district of northwest China.

  3. Simulating Crop Evapotranspiration Response under Different Planting Scenarios by Modified SWAT Model in an Irrigation District, Northwest China.

    Science.gov (United States)

    Liu, Xin; Wang, Sufen; Xue, Han; Singh, Vijay P

    2015-01-01

    Modelling crop evapotranspiration (ET) response to different planting scenarios in an irrigation district plays a significant role in optimizing crop planting patterns, resolving agricultural water scarcity and facilitating the sustainable use of water resources. In this study, the SWAT model was improved by transforming the evapotranspiration module. Then, the improved model was applied in Qingyuan Irrigation District of northwest China as a case study. Land use, soil, meteorology, irrigation scheduling and crop coefficient were considered as input data, and the irrigation district was divided into subdivisions based on the DEM and local canal systems. On the basis of model calibration and verification, the improved model showed better simulation efficiency than did the original model. Therefore, the improved model was used to simulate the crop evapotranspiration response under different planting scenarios in the irrigation district. Results indicated that crop evapotranspiration decreased by 2.94% and 6.01% under the scenarios of reducing the planting proportion of spring wheat (scenario 1) and summer maize (scenario 2) by keeping the total cultivated area unchanged. However, the total net output values presented an opposite trend under different scenarios. The values decreased by 3.28% under scenario 1, while it increased by 7.79% under scenario 2, compared with the current situation. This study presents a novel method to estimate crop evapotranspiration response under different planting scenarios using the SWAT model, and makes recommendations for strategic agricultural water management planning for the rational utilization of water resources and development of local economy by studying the impact of planting scenario changes on crop evapotranspiration and output values in the irrigation district of northwest China.

  4. A Study of the Atmospheric Boundary Layer Structure During a Clear Day in the Arid Region of Northwest China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qiang; WANG Sheng

    2009-01-01

    The local climate and atmospheric circulation pattern exert a clear influence on the atmospheric boundary layer (ABL) formation and development in Northwest China. In this paper, we use field observational data to analyze the distribution and characteristics of the ABL in the extremely arid desert in Dunhuang, Northwest China. These data show that the daytime convective boundary layer and night time stable boundary layer in this area extend to higher altitudes than in other areas. In the night time, the stable boundary layer exceeds 900 m in altitude and can sometimes peak at 1750 m, above which the residual layer may reach up to about 4000 m. The daytime convective boundary layer develops rapidly after entering the residual layer, and exceeds 4000 m in thickness. The results show that the deep convective boundary layer in the daytime is a pre-requisite for maintaining the deep residual mixed layer in the night time. Meanwhile, the deep residual mixed layer in the night time provides favorable thermal conditions for the development of the convective boundary layer in the daytime. The prolonged periods of clear weather that often occurs in this area allow the cumulative effect of the atmospheric residual layer to develop fully, which creates thermal conditions beneficial for the growth of the daytime convective boundary layer. At the same time, the land surface process and atmospheric motion within the surface layer in this area also provide helpful support for forming the particular structure of the thermal ABL. High surface temperature is clearly the powerful external thermal forcing for the deep convective boundary layer. Strong sensible heat flux in the surface layer provides the required energy. Highly convective atmosphere and strong turbulence provide the necessary dynamic conditions, and the accumulative effect of the residual layer provides a favorable thermal environment.

  5. The occurrence, sources and spatial characteristics of soil salt and assessment of soil salinization risk in Yanqi basin, northwest China.

    Directory of Open Access Journals (Sweden)

    Zhang Zhaoyong

    Full Text Available In order to evaluate the soil salinization risk of the oases in arid land of northwest China, we chose a typical oasis-the Yanqi basin as the research area. Then, we collected soil samples from the area and made comprehensive assessment for soil salinization risk in this area. The result showed that: (1 In all soil samples, high variation was found for the amount of Ca2+ and K+, while the other soil salt properties had moderate levels of variation. (2 The land use types and the soil parent material had a significant influence on the amount of salt ions within the soil. (3 Principle component (PC analysis determined that all the salt ion values, potential of hydrogen (pHs and ECs fell into four PCs. Among them, PC1 (C1-, Na+, SO4(2-, EC, and pH and PC2 (Ca2+, K+, Mg2+and total amount of salts are considered to be mainly influenced by artificial sources, while PC3 and PC4 (CO3(- and HCO3(2- are mainly influenced by natural sources. (4 From a geo-statistical point of view, it was ascertained that the pH and soil salt ions, such as Ca2+, Mg2+ and HCO3(-, had a strong spatial dependency. Meanwhile, Na+ and Cl- had only a weak spatial dependency in the soil. (5 Soil salinization indicators suggested that the entire area had a low risk of soil salinization, where the risk was mainly due to anthropogenic activities and climate variation. This study can be considered an early warning of soil salinization and alkalization in the Yanqi basin. It can also provide a reference for environmental protection policies and rational utilization of land resources in the arid region of Xinjiang, northwest China, as well as for other oases of arid regions in the world.

  6. Diversification of plant species in arid Northwest China: species-level phylogeographical history of Lagochilus Bunge ex Bentham (Lamiaceae).

    Science.gov (United States)

    Meng, Hong-Hu; Zhang, Ming-Li

    2013-09-01

    Lagochilus occurs in the arid zones across temperate steppe and desert regions of Northwest China. Cooling with strong dessication in the Pleistocene, along with rapid uplift of mountain ranges peripheral to the Qinghai-Tibet Plateau, appear to have had major impacts on the genetic structure of the flora. To understand the evolutionary history of Lagochilus and the divergence related to these past shifts of habitats among these regions, we sequenced the plastid intergenic spacers, psbA-trnH and trnS-trnG from populations throughout the known distributions of ten species of the genus. We investigated species-level phylogeographical patterns within Lagochilus. Phylogenetic trees were constructed using Neighbor-joining and Bayesian inference. The divergence times of major lineages were estimated with BEAST and IMa. Genetic structure and demographic history were inferred by AMOVA, neutrality tests, mismatch distribution, and Bayesian skyline plot analyses. The results showed that most chloroplast haplotypes were species-specific, and that the phylogeny of Lagochilus is geographically structured. The estimated Bayesian chronology and IMa suggested that the main divergence events for species between major eastern and western portions of the Chinese desert occurred at the Plio-/Pleistocene boundary (ca. 2.1-2.8 Ma ago), and likely coinciding with the formation of these deserts in Northwest China. The regional demographic expansions, in the western region at ca. 0.39 Ma, and in the eastern at ca. 0.06 Ma, or across all regions at ca. 0.26 Ma, showed the response to aridification accompanied by cooling of the Pleistocene sharply increased aridity in the Chinese deserts, which reflects a major influence of geologic and climatic events on the evolution of species of Lagochilus. We suggest that diversification is most likely the result of the past fragmentation due to aridification; the expansion of the range of species along with the deserts was an adaptation to dry and cold

  7. Phylogeographic patterns of Lygus pratensis (Hemiptera: Miridae): Evidence for weak genetic structure and recent expansion in northwest China

    Science.gov (United States)

    Zhang, Li-Juan; Cai, Wan-Zhi; Luo, Jun-Yu; Zhang, Shuai; Wang, Chun-Yi; Lv, Li-Min; Zhu, Xiang-Zhen; Wang, Li; Cui, Jin-Jie

    2017-01-01

    Lygus pratensis (L.) is an important cotton pest in China, especially in the northwest region. Nymphs and adults cause serious quality and yield losses. However, the genetic structure and geographic distribution of L. pratensis is not well known. We analyzed genetic diversity, geographical structure, gene flow, and population dynamics of L. pratensis in northwest China using mitochondrial and nuclear sequence datasets to study phylogeographical patterns and demographic history. L. pratensis (n = 286) were collected at sites across an area spanning 2,180,000 km2, including the Xinjiang and Gansu-Ningxia regions. Populations in the two regions could be distinguished based on mitochondrial criteria but the overall genetic structure was weak. The nuclear dataset revealed a lack of diagnostic genetic structure across sample areas. Phylogenetic analysis indicated a lack of population level monophyly that may have been caused by incomplete lineage sorting. The Mantel test showed a significant correlation between genetic and geographic distances among the populations based on the mtDNA data. However the nuclear dataset did not show significant correlation. A high level of gene flow among populations was indicated by migration analysis; human activities may have also facilitated insect movement. The availability of irrigation water and ample cotton hosts makes the Xinjiang region well suited for L. pratensis reproduction. Bayesian skyline plot analysis, star-shaped network, and neutrality tests all indicated that L. pratensis has experienced recent population expansion. Climatic changes and extensive areas occupied by host plants have led to population expansion of L. pratensis. In conclusion, the present distribution and phylogeographic pattern of L. pratensis was influenced by climate, human activities, and availability of plant hosts. PMID:28369108

  8. A toxic endophyte-infected grass helps reverse degradation and loss of biodiversity of over-grazed grasslands in northwest China.

    Science.gov (United States)

    Yao, Xiang; Christensen, Michael J; Bao, Gensheng; Zhang, Chunping; Li, Xiuzhang; Li, Chunjie; Nan, Zhibiao

    2015-12-18

    Overgrazing of China's grasslands is increasingly causing biodiversity to decline. In degenerated grasslands of northwest China endophyte (Epichloё gansuensis) infected Achnatherum inebrians (drunken horse grass) is becoming widely distributed because of its toxicity to livestock. In this study, we investigated the ecological consequences of endophyte toxicity in this native grass, at three sites in northwest China, by comparing seed production of plant species and arthropod abundance in overgrazed grasslands with and without the presence of A. inebrians. Our findings demonstrate that the presence of endophyte infected A. inebrians reduces the loss of plant and arthropod biodiversity by providing a protected nursery free of animal grazing. Therefore, A. inebrians, typically regarded as an unwanted toxic invader by pastoralists, should be viewed as beneficial for grasslands as its presence maintains plant and arthropod biodiversity, and provides a foundation stone in the reconstruction and restoration of these grassland ecosystems.

  9. Fruit and vegetable consumption and risk of esophageal cancer: a case-control study in north-west China.

    Science.gov (United States)

    Tang, L; Lee, A H; Xu, F; Zhang, T; Lei, J; Binns, C W

    2014-01-01

    The north-western region of China carries a big burden of esophageal cancer with incidence above the national average. This study ascertained the association between fruit and vegetable consumption and the risk of esophageal cancer in this remote part of China. A case-control study was undertaken in Urumqi and Shihezi, Xinjiang Uyghur Autonomous Region of China, between 2008 and 2009. Participants were 359 incident esophageal cancer patients and 380 hospital-based controls. Information on habitual fruit and vegetable consumption was obtained by face-to-face interview using a validated semiquantitative food frequency questionnaire. Unconditional logistic regression analyses were performed to assess the strength of the associations. The esophageal cancer patients consumed significantly less fruits (mean 364.3, standard deviation [SD] 497.4 g) and vegetables (mean 711.4, SD 727.9 g) daily than their counterparts without the disease (mean 496.5, SD 634.4 g and mean 894.5, SD 746.1 g, respectively). The adjusted odds ratios were 0.48 (95% confidence interval 0.33-0.71) and 0.46 (95% confidence interval 0.32-0.68) for consuming at least 515 g of fruits and 940 g of vegetables per day, respectively, relative to at most 170 g and 520 g. With respect to nutrients contained in fruits and vegetables, intakes of vitamin C, vitamin E, β-cryptoxanthin, potassium, and magnesium at high levels also reduced the esophageal cancer risk. In conclusion, inverse associations were evident between consumption of fruits and vegetables and the risk of esophageal cancer for adults residing in north-west China.

  10. Genomic analyses of metal resistance genes in three plant growth promoting bacteria of legume plants in Northwest mine tailings, China.

    Science.gov (United States)

    Xie, Pin; Hao, Xiuli; Herzberg, Martin; Luo, Yantao; Nies, Dietrich H; Wei, Gehong

    2015-01-01

    To better understand the diversity of metal resistance genetic determinant from microbes that survived at metal tailings in northwest of China, a highly elevated level of heavy metal containing region, genomic analyses was conducted using genome sequence of three native metal-resistant plant growth promoting bacteria (PGPB). It shows that: Mesorhizobium amorphae CCNWGS0123 contains metal transporters from P-type ATPase, CDF (Cation Diffusion Facilitator), HupE/UreJ and CHR (chromate ion transporter) family involved in copper, zinc, nickel as well as chromate resistance and homeostasis. Meanwhile, the putative CopA/CueO system is expected to mediate copper resistance in Sinorhizobium meliloti CCNWSX0020 while ZntA transporter, assisted with putative CzcD, determines zinc tolerance in Agrobacterium tumefaciens CCNWGS0286. The greenhouse experiment provides the consistent evidence of the plant growth promoting effects of these microbes on their hosts by nitrogen fixation and/or indoleacetic acid (IAA) secretion, indicating a potential in-site phytoremediation usage in the mining tailing regions of China. Copyright © 2014. Published by Elsevier B.V.

  11. Genomic analyses of metal resistance genes in three plant growth promoting bacteria of legume plants in Northwest mine tailings, China

    Institute of Scientific and Technical Information of China (English)

    Pin Xie; Xiuli Hao; Martin Herzberg; Yantao Luo; Dietrich H.Nies; Gehong Wei

    2015-01-01

    To better understand the diversity of metal resistance genetic determinant from microbes that survived at metal tailings in northwest of China,a highly elevated level of heavy metal containing region,genomic analyses was conducted using genome sequence of three native metal-resistant plant growth promoting bacteria (PGPB).It shows that:Mesorhizobium amorphae CCNWGS0123 contains metal ~nsporters from P-type ATPase,CDF (Cation Diffusion Facilitator),HupE/UreJ and CHR (chromate ion transporter) family involved in copper,zinc,nickel as well as chromate resistance and homeostasis.Meanwhile,the putative CopA/CueO system is expected to mediate copper resistance in Sinorhizobium meliloti CCNWSX0020 while ZntA transporter,assisted with putative CzcD,determines zinc tolerance in Agrobacterium tumefaciens CCNWGS0286.The greenhouse experiment provides the consistent evidence of the plant growth promoting effects of these microbes on their hosts by nitrogen fixation and/or indoleacetic acid (IAA) secretion,indicating a potential in-site phytoremediation usage in the mining tailing regions of China.

  12. Multi-proxy evidence for Late Pleistocene-Holocene climatic and environmental changes in Lop-Nur, Xinjiang, Northwest China

    Science.gov (United States)

    Luo, C.; Yang, D.; Peng, Z.; Zhang, Z.; Weiguo, L.; He, J.; Zhou, C.

    2008-01-01

    A 10.35-m-long sediment core from the Luobei depression in Lop-Nur, Xinjiang, Northwest China, provides detailed information about environmental changes during the Late Pleistocene. The samples taken every 5 cm of the core were analyzed for 10 environmental proxies, including magnetic susceptibility, granularity, chroma, carbonate and loss on ignition (LOI), and pH value. The chronology data are provided by the uranium/thorium disequilibrium dates. The sediments of the section were deposited during the last 32000 years. The results of analysis of 10 proxies were examined using multivariate statistical analysis, and the principal components were calculated. According to the results, the Late Pleistocene sequence contains four climatic and environmental stages appearing in the cycles of cold-wet and warm-dry changes. During 10-9 ka BP, it was the earliest warm episode in the Holocene. Environmental changes in this district were restricted by global change, as suggested by the analysis of glacial-interglacial cycles. But it was different from the mutative trend of a monsoon region in East China because of its own characteristics, which was the situation of cold-wet and warm-dry climate-environment change. The candidate reason may be the uplift of the Tibet Plateau and the westerly wind circulation. ?? Science Press, Institute of Geochemistry, CAS and Springer-Verlag GmbH 2008.

  13. Multi-proxy evidence for Late Pleistocene Holocene climatic and environmental changes in Lop-Nur, Xinjiang, Northwest China

    Institute of Scientific and Technical Information of China (English)

    LUO Chao; YANG Dong; PENG Zicheng; ZHANG Zhaofeng; LIU Weiguo; HE Jianfeng; ZHOU Chenlin

    2008-01-01

    A 10.35-m-long sediment core from the Luobei depression in Lop-Nur, Xinjiang, Northwest China, provides detailed information about environmental changes during the Late Pleistocene. The samples taken every 5 cm of the core were unalyzed for 10 environmental proxies, including magnetic susceptibility, granularity, chroma, carbonate and loss on ignition (LOI), and pH value. The chronology data are provided by the uranium/thorium disequilibrium dates. The sediments of the section were deposited during the last 32000 years. The results of analysis of 10 proxies were examined using multivariate statistical analysis, and the principal components were calculated. According to the results, the Late Pleistocene sequence contains four climatic and environmental stages appearing in the cycles of cold-wet and warm-dry changes. During 10-9 ka BP, it was the earliest warm episode in the Holocene.Environmental changes in this district were restricted by global change, as suggested by the analysis of glacial-interglacial cycles. But it was different from the mutative trend of a monsoon region in East China because of its own characteristics, which was the situation of cold-wet and warm-dry climate-environment change. The candidate reason may be the uplift of the Tibet Plateau and the westerly wind circulation.

  14. Pollution of intensively managed greenhouse soils by nutrients and heavy metals in the Yellow River Irrigation Region, Northwest China.

    Science.gov (United States)

    Kong, Xiaole; Cao, Jing; Tang, Rangyun; Zhang, Shengqiang; Dong, Fang

    2014-11-01

    The present study aimed to assess the potential ecological risk of heavy metals and nutrient accumulation in polytunnel greenhouse soils in the Yellow River irrigation region (YRIR), Northwest China, and to identify the potential sources of these heavy metals using principal component analysis. Contents of available nitrogen (AN), phosphorus (AP), and potassium (AK) in the surface polytunnel greenhouse soils (0-20 cm) varied from 13.42 to 486.78, from 39.10 to 566.97, and from 21.64 to 1,156.40 mg kg(-1), respectively, as well as AP, soil organic matter (SOM) and AK contents tended to increase significantly at the 0-20- and 20-40-cm soil layers. Heavy metal accumulations occurred in the polytunnel greenhouse soils as compared to arable soils, especially at a depth of 20 cm where Cd, Zn and Cu contents were significantly higher than arable soil. Cd and As were found to be the two main polluting elements in the greenhouse soils because their contents exceeded the thresholds established for greenhouse vegetable production HJ333-2006 in China and the background of Gansu province. It has been shown that Cd, Cu, Pb and Zn at the 0-20-cm soil layer were derived mainly from agricultural production activities, whereas contents of Cr and Ni at the same soil layer were determined by 'natural' factors and As originated from natural sources, deposition and irrigation water.

  15. Aerosol size distribution and new particle formation events in the suburb of Xi'an, northwest China

    Science.gov (United States)

    Peng, Yan; Liu, Xiaodong; Dai, Jin; Wang, Zhao; Dong, Zipeng; Dong, Yan; Chen, Chuang; Li, Xingmin; Zhao, Na; Fan, Chao

    2017-03-01

    Particle number concentration and size distribution are important for better understanding the characteristics of aerosols. However, their measurements are scarce in western China. Based on the first measurement of particle number size distribution (10-487 nm) in the suburb of Xi'an, northwest China from November 2013 to December 2014, the seasonal, monthly and diurnal average particle number concentrations were investigated, and the characteristics of new particle formation (NPF) events and their dependencies on meteorological parameters also discussed. The results showed that the annual average particle number concentrations in the nucleation (NNUC), Aitken (NAIT), and Accumulation (NACC) size ranges were 960 cm-3, 4457 cm-3, 3548 cm-3, respectively. The mean total particle number concentration (NTOT) was 8965 cm-3 and largely dominated by particles in Aitken mode. The number concentration was dominated by particles around 67.3 nm in spring, summer and fall, while about 89.8 nm in winter. The percentage of the ultrafine size range (UFP, particles of diameter below 100 nm) to total particle number concentration was 63.2%, 69.6%, 62.2% and 58.1% in four seasons. The diurnal variation of the nucleation mode particles was mainly influenced by NPF events in summer, while by both traffic densities and NPF events in spring, fall and winter. The diurnal variation of the number concentration of Aitken mode particles correlated with the traffic emission in spring, fall and winter, while in summer it more correlated with contribution of the growth of the nucleation mode particles. The burst of nucleation mode particles typically started in the daytime (08:15-16:05, LST). The growth rates of nucleated particles ranged from 2.8 to 10.7 nm h-1 with an average of 5.0 ± 1.9 nm h-1. Among observed 66 NPF events from 347 effective measurement days, 85 percent of their air masses came from north or northwest China, resulting in a low concentration of pre-existing particles, and

  16. Ulocladium cantlous sp. nov. isolated from Northwest China: morphology and molecular phylogenetic position

    Science.gov (United States)

    A new species of Ulocladium was isolated from diseased leaves from two Cucumis spp. growing in Sinkiang and Gansu Provinces of China. Conidia were isolated from diseased leaf areas, grown in single-spore pure culture, and conidia harvested 1, 3, and 7 days after incubation for morphological comparis...

  17. A Year as an Educator in Northwest China. World Education Monograph Series, Number Two.

    Science.gov (United States)

    Elias, Richard F.

    Chinese children must attend school until age 16, and education consists of elementary schools for ages 6-13 and lower middle schools for ages 13-16. While the economic planning of the national government in Beijing (China) dictates what will be emphasized, the school curriculum includes instruction in ideology, Chinese language, calligraphy, fine…

  18. Modification of evapotranspiration model based on effective resistance to estimate evapotranspiration of maize for seed production in an arid region of northwest China

    Science.gov (United States)

    Jiang, Xuelian; Kang, Shaozhong; Tong, Ling; Li, Fusheng

    2016-07-01

    To estimate evapotranspiration (ET) of heterogeneous canopy of maize for seed production accurately, an ET model was developed based on effective resistance after field experiments were conducted from March to September in 2013 and 2014 in an arid region of northwest China. The effective resistance of maize including effective surface (rce) and aerodynamic (rae) resistance was estimated using different methods, and then the Penman-Monteith model (P-M model) based on effective resistance was used to estimate daily ET of maize over the whole growing stage. Results showed that when the fraction cover of the canopy (fc) = 1, the estimated rce by aggregating female and male canopy resistances in parallel, was closer to the measured rce (rcec), which was obtained by inverting the P-M model based on effective resistance using measured ET by the eddy covariance (EC) system. When fc maize for seed production in the arid region of northwest China.

  19. A decade of change in breastfeeding in China's far north-west

    Directory of Open Access Journals (Sweden)

    Xiao Cuiqin

    2006-11-01

    Full Text Available Abstract Background There have been considerable changes in breastfeeding practices in China over the past forty years. However China is a very large country, and breastfeeding rates in different parts of China vary considerably. The objective of this paper is to identify and compare breastfeeding types and rates between 1994–1996 and 2003–2004 in Shihezi, Xinjiang Uygur Autonomous Region, PR China. Methods In 1994–1996, a study of breastfeeding (n = 2197 was undertaken in Shihezi, Xinjiang, PR China. A decade later in 2003–2004, a longitudinal study (n = 545 of infant feeding practices was undertaken in the same area. Results The 'any breastfeeding' rates at 1, 4 and 6 months were 94%, 82% and 78% respectively in the early 1990s. A decade later, breastfeeding at 1 month was lower, but rates at 4 and 6 months remained the same. In 2004 the 'full breastfeeding' rate at one month was significantly higher (57% than a decade earlier (38%, but after 3 months there was a rapid decline. This reflected a shift in the way complementary foods are introduced: the initial introduction was later, but by a higher proportion of mothers. Conclusion The rate of breastfeeding at one month is significantly lower in 2003–2004 when compared to 1994–1996. The 'full breastfeeding' rates were initially higher, but after 3 months were then lower. The Chinese national breastfeeding targets were not reached in either period of the study. These studies show the need to further promote full or exclusive breastfeeding and further longitudinal studies are necessary to provide the detailed knowledge about risk factors required for health promotion programs.

  20. Modelling the effects of climate and land use change on the hydrological system of Urumqi, Northwest China

    Science.gov (United States)

    Fricke, K.; Bubenzer, O.

    2012-04-01

    This case study is about the hydrological system of Urumqi City, Northwest China, where the effects of climate change and land use change until 2050 are modelled. The research is part of the BMBF-funded project "RECAST Urumqi - Meeting the Resource Efficiency Challenge in a Climate Sensitive Dryland Megacity Environment". Northwest China is a region where notable climate change takes place. Regional climate has shifted during the last 30 years to a wetter regime, while at the same time exhibiting rising temperatures. The provincial capital Urumqi is a fast expanding economic and industrial centre, leading to enforced and notable land use change around the city. The hydrological effects of both drivers have to be assessed to allow customized adaptation to the inevitable changes. The hydrological model is based on the water balance equation and uses partly physically based modules e.g. to calculate potential evapotranspiration with the Penman-Monteith formula and partly index based modules e.g. to simulate snow melt water and surface runoff. The main challenge when applying the model was the lack of field research and hydrological data such as measured runoff or groundwater recharge. Hence, input data was almost completely collected from afar, from climate and soil databases and remote sensing (land use and cover, spatial distribution of land surface temperature and precipitation). The hydrological model was calibrated at one of the upper sub-catchments with good results for the total annual runoff volume but low values for the Nash-Sutcliffe model efficiency coefficient. In order to assess the annual water balance, the methodology was transferred to the whole catchment area. The hydrological behaviour of the other sub-catchments was assumed to be comparable to the calibrated one, applying the concept of predicting ungauged basins based on similar characteristics of the hydrological system. Future scenarios that were modelled include on the one hand the projection of

  1. A Picea crassifolia Tree-Ring Width-Based Temperature Reconstruction for the Mt. Dongda Region, Northwest China, and Its Relationship to Large-Scale Climate Forcing.

    Science.gov (United States)

    Liu, Yu; Sun, Changfeng; Li, Qiang; Cai, Qiufang

    2016-01-01

    The historical May-October mean temperature since 1831 was reconstructed based on tree-ring width of Qinghai spruce (Picea crassifolia Kom.) collected on Mt. Dongda, North of the Hexi Corridor in Northwest China. The regression model explained 46.6% of the variance of the instrumentally observed temperature. The cold periods in the reconstruction were 1831-1889, 1894-1901, 1908-1934 and 1950-1952, and the warm periods were 1890-1893, 1902-1907, 1935-1949 and 1953-2011. During the instrumental period (1951-2011), an obvious warming trend appeared in the last twenty years. The reconstruction displayed similar patterns to a temperature reconstruction from the east-central Tibetan Plateau at the inter-decadal timescale, indicating that the temperature reconstruction in this study was a reliable proxy for Northwest China. It was also found that the reconstruction series had good consistency with the Northern Hemisphere temperature at a decadal timescale. Multi-taper method spectral analysis detected some low- and high-frequency cycles (2.3-2.4-year, 2.8-year, 3.4-3.6-year, 5.0-year, 9.9-year and 27.0-year). Combining these cycles, the relationship of the low-frequency change with the Pacific Decadal Oscillation (PDO), North Atlantic Oscillation (NAO) and Southern Oscillation (SO) suggested that the reconstructed temperature variations may be related to large-scale atmospheric-oceanic variations. Major volcanic eruptions were partly reflected in the reconstructed temperatures after high-pass filtering; these events promoted anomalous cooling in this region. The results of this study not only provide new information for assessing the long-term temperature changes in the Hexi Corridor of Northwest China, but also further demonstrate the effects of large-scale atmospheric-oceanic circulation on climate change in Northwest China.

  2. Preliminary investigation on geographic distribution of Aedes albopictus in northwest China%西北地区白纹伊蚊地理分布初步调查

    Institute of Scientific and Technical Information of China (English)

    施耀勇; 张军民

    2012-01-01

    目的 调查了解白纹伊蚊在西北地区的分布.方法 帐诱、人诱法、畜诱法、网捕法和文献资料收集.结果 白纹伊蚊在陕西省除陕北黄土高原外遍布大部分地区;甘肃省仅在文县、康县、徽县、成县和两当县发现有白纹伊蚊;在宁夏和青海采集的大量标本中没有发现白纹伊蚊.结论 白纹伊蚊在西北地区分布的界限有向西扩大.%Objective To clarify the geographical distribution oi Aedes albopictus in northwest China. Methods Using bedent snars, person soars, animal snars and insert net to collect Aedes alhopictus from northwest China. Results Aedes albopictus distributed in most parts oi Shanxi Province, except the Shanbei plateau; but Aedes albopic-lus was only found in Wen County, Kang County,Cheng County and Liangdang County in Gansu Province;Aedes albopictus was not found in the large number of specimens collected in Ningxia Province and Qinghai Province. Conclusion Distribution boundaries of Aedes albopictus in the northwest China is expanding westward.

  3. Estimation of the Threshold Friction Velocities over Various Dust Storm Source Areas in Northwest China

    Institute of Scientific and Technical Information of China (English)

    ZHU Hao; ZHANG Hongsheng

    2010-01-01

    The emission of dust particles into the atmosphere is governed by the aerodynamic and resistant factors, which are quantified by the friction velocity u. and the threshold friction velocity u*t, respectively. The threshold friction velocity u*t influences the vertical dust flux and dust transport. Based on the micro-meteorological data obtained in the springs of 2004 and 2006 over Hunshandake desert area, Loess Plateau, and Gobi desert area, the relationship between dust concentration and friction velocity for the dust events that occurred over Hunshandake desert area was investigated, and the threshold friction velocities over the three different dust source areas were estimated. The results show that the value of dust concentration is low during the pre-emission stage of a dust storm event, and the rapid increase of friction velocity provides favor-able dynamic conditions for dust emission. During the dust emission stage, the dust concentration increases sharply due to mechanical and thermal turbulent mixing. At the calm-down stage, the dust concentration drops nearly linearly with the decreasing friction velocity, on account of the gravitational deposition of larger dust particles. When the dust concentration is higher than 200 μgm-3, it is considered as a dust emission process. According to the criteria, the values of threshold friction velocity over Hunshandake desert area and Gobi region are 0.6 and 0.45 m s-1, respectively. The threshold friction velocity over Loess Plateau depends on the wind direction, due to the complex terrain and inhomogeneous surface. The northwest wind shows the effects of the Mu Us desert in the northwest. The corresponding u*t is 0.35 m s-1. The south wind exhibits the characteristics of the Loess hilly dunes in the south, and the u*t is 0.7 m s-1. The large roughness length of the Loess hilly dunes and the large inter-particle cohesion for the clay soil texture increases the local friction velocity. Different threshold friction

  4. Methane-metabolizing microbial communities in sediments of the Haima cold seep area, northwest slope of the South China Sea.

    Science.gov (United States)

    Niu, Mingyang; Fan, Xibei; Zhuang, Guangchao; Liang, Qianyong; Wang, Fengping

    2017-09-01

    Cold seeps are widespread chemosynthetic ecosystems in the deep-sea environment, and cold seep microbial communities of the South China Sea are poorly constrained. Here we report on the archaeal communities, particularly those involved in methane metabolization, in sediments of a newly discovered cold seep (named 'Haima') on the northwest slope of the South China Sea. Archaeal diversity, abundance and distribution were investigated in two piston cores collected from a seep area (QDN-14B) and a non-seep control site (QDN-31B). Geochemical investigation of the QDN-14B core identified an estimated sulfate-methane transition zone (Estimated SMTZ) at 300-400 cm below sea floor (cmbsf), where a high abundance of anaerobic methane-oxidizing archaea (ANME) occurred, as revealed by analysis of the 16S rRNA gene and the gene (mcrA) encoding the α-subunit of the key enzyme methyl-coenzyme M reductase. ANME-2a/b was predominant in the upper and middle layers of the estimated SMTZ, whereas ANME-1b outcompeted ANME-2 in the sulfate-depleted bottom layers of the estimated SMTZ and the methanogenic zone. Fine-scale phylogenetic analysis further divided the ANME-1b group into three subgroups with different distribution patterns: ANME-1bI, ANME-1bII and ANME-1bIII. Multivariate analyses indicated that dissolved inorganic carbon and sulfate may be important factors controlling the composition of the methane-metabolizing community. Our study on ANME niche separation and interactions with other archaeal groups improves our understanding of the metabolic diversity and flexibility of ANME, and the findings further suggest that ANME subgroups may have evolved diversified/specified metabolic capabilities other than syntrophic anaerobic oxidation of methane coupled with sulfate reduction in marine sediments. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Ozone concentrations, flux and potential effect on yield during wheat growth in the Northwest-Shandong Plain of China.

    Science.gov (United States)

    Zhu, Zhilin; Sun, Xiaomin; Zhao, Fenghua; Meixner, Franz X

    2015-08-01

    Ozone (O3) concentration and flux (Fo) were measured using the eddy covariance technique over a wheat field in the Northwest-Shandong Plain of China. The O3-induced wheat yield loss was estimated by utilizing O3 exposure-response models. The results showed that: (1) During the growing season (7 March to 7 June, 2012), the minimum (16.1 ppbV) and maximum (53.3 ppbV) mean O3 concentrations occurred at approximately 6:30 and 16:00, respectively. The mean and maximum of all measured O3 concentrations were 31.3 and 128.4 ppbV, respectively. The variation of O3 concentration was mainly affected by solar radiation and temperature. (2) The mean diurnal variation of deposition velocity (Vd) can be divided into four phases, and the maximum occurred at noon (12:00). Averaged Vd during daytime (6:00-18:00) and nighttime (18:00-6:00) were 0.42 and 0.14 cm/sec, respectively. The maximum of measured Vd was about 1.5 cm/sec. The magnitude of Vd was influenced by the wheat growing stage, and its variation was significantly correlated with both global radiation and friction velocity. (3) The maximum mean Fo appeared at 14:00, and the maximum measured Fo was -33.5 nmol/(m(2)·sec). Averaged Fo during daytime and nighttime were -6.9 and -1.5 nmol/(m(2)·sec), respectively. (4) Using O3 exposure-response functions obtained from the USA, Europe, and China, the O3-induced wheat yield reduction in the district was estimated as 12.9% on average (5.5%-23.3%). Large uncertainties were related to the statistical methods and environmental conditions involved in deriving the exposure-response functions.

  6. Assessment of spatial and temporal patterns of green and blue water flows in inland river basins in Northwest China

    Directory of Open Access Journals (Sweden)

    C. F. Zang

    2012-03-01

    Full Text Available In arid and semi-arid regions freshwater resources have become scarcer with increasing demands from socio-economic development and population growth. Until recently, water research and management in these has mainly focused on blue water but ignored green water. Here we report on spatial and temporal patterns of both blue and green water flows simulated by the Soil and Water Assessment Tool (SWAT for the Heihe river basin, the second largest inland river basin in Northwest China. Calibration and validation at two hydrological stations show good performance of the SWAT model in modelling hydrological processes. The total green and blue water flows were 22.09 billion m3 in the 2000s for the Heihe river basin. Blue water flows are larger in upstream sub-basins than in downstream sub-basins mainly due to high precipitation and large areas of glaciers in upstream. Green water flows are distributed more homogeneously among different sub-basins. The green water coefficient was 88.0% in the 2000s for the entire river basin, varying from around 80–90% in up- and mid-stream sub-basins to above 95% in downstream sub-basins. This is much higher than reported green water coefficient in many other river basins. The spatial patterns of green water coefficient were closely linked to dominant land covers (e.g. glaciers in upstream and desert in downstream and climate conditions (e.g. high precipitation in upstream and low precipitation in downstream. There are no clear consistent historical trends of change in green and blue water flows and green water coefficient at both the river basin and sub-basin levels. This study provides insights into green and blue water endowments for the entire Heihe river basin at sub-basin level. The results are helpful for formulating reasonable water policies to improve water resources management in the inland river basins of China.

  7. Assessing water footprint at river basin level: a case study for the Heihe River Basin in northwest China

    Directory of Open Access Journals (Sweden)

    Z. Zeng

    2012-05-01

    Full Text Available Increasing water scarcity places considerable importance on the quantification of water footprint (WF at different levels. Despite progress made previously, there are still very few WF studies focusing on specific river basins, especially for those in arid and semi-arid regions. The aim of this study is to quantify WF within the Heihe River Basin (HRB, a basin located in the arid and semi-arid northwest of China. The findings show that the WF was 1768 million m3 yr−1 in the HRB over 2004–2006. Agricultural production was the largest water consumer, accounting for 96% of the WF (92% for crop production and 4% for livestock production. The remaining 4% was for the industrial and domestic sectors. The "blue" component of WF was 811 million m3 yr−1. This indicates a blue water proportion of 46%, which is much higher than the world average and China's average, which is mainly due to the aridness of the HRB and a high dependence on irrigation for crop production. However, even in such a river basin, blue WF was still smaller than green WF, indicating the importance of green water. We find that blue WF exceeded blue water availability during eight months per year and also on an annual basis. This indicates that WF of human activities was achieved at a cost of violating environmental flows of natural freshwater ecosystems, and such a WF pattern is not sustainable. Considering the large WF of crop production, optimizing the crop planting pattern is often a key to achieving more sustainable water use in arid and semi-arid regions.

  8. Farmers' Perception and Adaptation Behavior Concerning Land Degradation: A Theoretical Framework and a Case Study in Northwest China

    Science.gov (United States)

    Hou, Deyi; Liu, Kai

    2017-04-01

    In an era of global environmental change, social actors from an individual level to a national level are increasingly seeking adaptation strategies to better manage risks from environmental hazards. Vulnerability arises where adaptation capacity is not sufficient in dealing with a changing environment. Adaptation on an individual level and community level is important because of the location specific nature of environmental change. Land degradation is drawing much attention from both governments and academics, because it tends to affect the most vulnerable human populations and ecological systems most significantly. Despite these efforts, there is limited scientific knowledge regarding how farmers at a local level perceive the risks associated with degraded land and how their background, attitude, and living situation may affect their adaptation behavior. This poses a challenge to policy makers who are tasked to enhance the resilience of the society in response to environmental changes. Degradation of land by pollutant chemicals is particularly serious in China due to aggressive urbanization and industrialization activities over the last four decades. A report by the Ministry of Environmental Protection (MEP) in 2014 suggested that 16.1 percent of the nation's soil is polluted. Other studies suggest that shallow groundwater contamination is even more wide spread, with 80 90 percent being polluted. The government has realized the seriousness of land contamination, and vowed to give high priority to land remediation. Millions of hectares of contaminated agricultural land are expected to be remediated over the next decade. However, farmer's perception and adaptation behavior under this social and environmental change remain unknown. In this presentation, we report a conceptual framework and research hypothesis based on theoretical methodologies found in existing literature. We applied this framework to a case study of degraded land in an arid region in Northwest of

  9. Effects of Sand Dune Stabilization on the Spatial Pattern of Artemisia ordosica Population in Mu Us Desert, Northwest China.

    Science.gov (United States)

    Zhang, Jiachen; Zhang, Yuqing; Fan, Dongqing; Qin, Shugao; Jia, Xin; Wu, Bin; Chen, Dong; Gao, Hao; Zhu, Linfeng

    2015-01-01

    Vegetation patterns are strongly influenced by sand mobility in desert ecosystems. However, little is known about the spatial patterns of Artemisia ordosica, a dominant shrub in the Mu Us desert of Northwest China, in relation to sand fixation. The aim of this study was to investigate and contrast the effects of sand dune stabilization on the population and spatial distribution of this desert shrub. Spatial autocorrelation, semi-variance analysis, and point-pattern analysis were used jointly in this study to investigate the spatial patterns of A. ordosica populations on dunes in Yanchi County of Ningxia, China. The results showed that the spatial autocorrelation and spatial heterogeneity declined gradually, and the distance between the clustered individuals shortened following sand dune fixation. Seedlings were more aggregated than adults in all stage of dune stabilization, and both were more aggregated on shifting sand dunes separately. Spatial associations of the seedlings with the adults were mostly positive at distances of 0-5 m in shifting sand dunes, and the spatial association changed from positive to neutral in semi-fixed sand dunes. The seedlings were spaced in an almost random pattern around the adults, and their distances from the adults did not seem to affect their locations in semi-fixed sand dunes. Furthermore, spatial associations of the seedlings with the adults were negative in the fixed sand dune. These findings demonstrate that sand stabilization is an important factor affecting the spatial patterns of A. ordosica populations in the Mu Us desert. These findings suggest that, strong association between individuals may be the mechanism to explain the spatial pattern formation at preliminary stage of dune fixation. Sand dune stabilization can change the spatial pattern of shrub population by weakening the spatial association between native shrub individuals, which may affect the development direction of desert shrubs.

  10. [Degradation characteristics, patterns, and processes of lakeside wetland in Napahai of northwest Yunnan Plateau, Southwest China].

    Science.gov (United States)

    Shang, Wen; Yang, Yong-Xing

    2012-12-01

    Two-way indicator species analysis (TWINSPAN) and canonical correspondence analysis (CCA) were employed to analyze the degradation characteristics, patterns, and processes of lakeside wetland in Napahai of northwest Yunnan Plateau. The plant communities in the lakeside wetland could be classified into four associations, according to the TWINSPAN results. The succession patterns of the plant community were represented by aquatic plant community --> swamp plant community --> swamp meadow plant community --> meadow plant community. During the processes of succession, the plant community coverage, density, Shannon diversity index, species richness, and plant aboveground biomass increased, whereas the community height decreased. The succession of the plant hydro-ecotypes followed the sequence of aquatic --> helophyte --> hygrophyte --> mesophyte. With the succession of the plant community, the wetland water quality indices salinity, alkalinity, and hardness decreased but ammonium nitrogen and total phosphorus concentrations increased, while total nitrogen and nitrate nitrogen concentrations showed no significant changes. Meanwhile, the soil pH and soil organic matter and total nitrogen contents decreased gradually, soil total phosphorous and potassium contents were increasing, whereas soil available phosphorous and potassium contents decreased after an initial increase. The CCA showed that the community species composition and structure were mainly affected by the wetland water gradient. The soil pH and total phosphorus content and the water total nitrogen and ammonium nitrogen concentrations had significant effects on the wetland plant species distribution and plant community succession.

  11. Multi-tracer investigation of river and groundwater interactions: a case study in Nalenggele River basin, northwest China

    Science.gov (United States)

    Xu, Wei; Su, Xiaosi; Dai, Zhenxue; Yang, Fengtian; Zhu, Pucheng; Huang, Yong

    2017-06-01

    Environmental tracers (such as major ions, stable and radiogenic isotopes, and heat) monitored in natural waters provide valuable information for understanding the processes of river-groundwater interactions in arid areas. An integrated framework is presented for interpreting multi-tracer data (major ions, stable isotopes (2H, 18O), the radioactive isotope 222Rn, and heat) for delineating the river-groundwater interactions in Nalenggele River basin, northwest China. Qualitative and quantitative analyses were undertaken to estimate the bidirectional water exchange associated with small-scale interactions between groundwater and surface water. Along the river stretch, groundwater and river water exchange readily. From the high mountain zone to the alluvial fan, groundwater discharge to the river is detected by tracer methods and end-member mixing models, but the river has also been identified as a losing river using discharge measurements, i.e. discharge is bidirectional. On the delta-front of the alluvial fan and in the alluvial plain, in the downstream area, the characteristics of total dissolved solids values, 222Rn concentrations and δ18O values in the surface water, and patterns derived from a heat-tracing method, indicate that groundwater discharges into the river. With the environmental tracers, the processes of river-groundwater interaction have been identified in detail for better understanding of overall hydrogeological processes and of the impacts on water allocation policies.

  12. An Integrative Approach to Understand the Climatic-Hydrological Process: A Case Study of Yarkand River, Northwest China

    Directory of Open Access Journals (Sweden)

    Jianhua Xu

    2013-01-01

    Full Text Available Taking the Yarkand River as an example, this paper conducted an integrative approach combining the Durbin-Watson statistic test (DWST, multiple linear regression (MLR, wavelet analysis (WA, coefficient of determination (CD, and Akaike information criterion (AIC to analyze the climatic-hydrological process of inland river, Northwest China from a multitime scale perspective. The main findings are as follows. (1 The hydrologic and climatic variables, that is, annual runoff (AR, annual average temperature, (AAT and annual precipitation (AP, are stochastic and, no significant autocorrelation. (2 The variation patterns of runoff, temperature, and precipitation were scale dependent in time. AR, AAT, and AP basically present linear trends at 16-year and 32-year scales, but they show nonlinear fluctuations at 2-year and 4-year scales. (3 The relationship between AR with AAT and AP was simulated by the multiple linear regression equation (MLRE based on wavelet analysis at each time scale. But the simulated effect at a larger time scale is better than that at a smaller time scale.

  13. Indices of central and general obesity and cardiometabolic risk among adolescents in three ethnic groups in north-west China.

    Science.gov (United States)

    Lek, Ngee; Yan, Weili; Zhang, Yi; Wang, Qian; Cheung, Yin Bun

    2016-01-01

    'A Body Shape Index-Adolescents' (ABSI-Adolescents) and waist-to-height ratio are recently proposed indices that quantify central obesity in adolescents. To investigate the scaling exponents to standardise waist circumference (WC) for body mass index (BMI) and height and to investigate the association between BMI, WC-based indices and cardiometabolic outcomes in adolescents of three ethnic groups. A cross-sectional study of 1755 adolescents (516 Hans, 565 Uygurs, 674 Kazakhs) was conducted in north-west China. Correlation between indices of obesity and blood pressure (BP) and fasting blood glucose (FBG) were estimated and compared. Two ethnic groups (Han and Kazakh) had WC-BMI-height profiles different from the previously proposed ABSI-Adolescents and, therefore, required different scaling exponents for WC standardization. After adjustment for age and gender, WC and BMI have similar associations with BP and FBG. After further adjustment for BMI, WC remained significantly associated with FBG in all three ethnic groups (each p adolescents (each p pressure and fasting blood glucose in adolescents of three ethnicities. The WC-based indices did not out-perform WC per se.

  14. C:N:P Stoichiometry and Leaf Traits of Halophytes in an Arid Saline Environment, Northwest China

    Science.gov (United States)

    Wang, Lilong; Zhao, Guanxiang; Li, Meng; Zhang, Mingting; Zhang, Lifang; Zhang, Xinfang; An, Lizhe; Xu, Shijian

    2015-01-01

    Salinization is an important and increasingly prevalent issue which has broad and profound effects on plant survival and distribution pattern. To understand the patterns and potential drivers of leaf traits in saline environments, we determined the soil properties, leaf morphological traits (specific leaf area, SLA, and leaf dry matter content, LDMC), leaf chemical traits (leaf carbon, C, nitrogen, N, and phosphorus, P, stoichiometry) based on 142 observations collected from 23 sites in an arid saline environment, which is a vulnerable ecosystem in northwest China. We also explored the relationships among leaf traits, the responses of leaf traits, and plant functional groups (herb, woody, and succulent woody) to various saline environments. The arid desert halophytes were characterized by lower leaf C and SLA levels, higher N, but stable P and N:P. The leaf morphological traits were correlated significantly with the C, N, and P contents across all observations, but they differed within each functional group. Succulent woody plants had the lowest leaf C and highest leaf N levels among the three functional groups. The growth of halophytes might be more limited by N rather than P in the study area. GLM analysis demonstrated that the soil available nutrients and plant functional groups, but not salinity, were potential drivers of leaf C:N:P stoichiometry in halophytes, whereas species differences accounted for the largest contributions to leaf morphological variations. Our study provides baseline information to facilitate the management and restoration of arid saline desert ecosystem. PMID:25798853

  15. Groundwater and surface-water interactions and impacts of human activities in the Hailiutu catchment, northwest China

    Science.gov (United States)

    Yang, Zhi; Zhou, Yangxiao; Wenninger, Jochen; Uhlenbrook, Stefan; Wang, Xusheng; Wan, Li

    2017-02-01

    The interactions between groundwater and surface water have been significantly affected by human activities in the semi-arid Hailiutu catchment, northwest China. Several methods were used to investigate the spatial and temporal interactions between groundwater and surface water. Isotopic and chemical analyses of water samples determined that groundwater discharges to the Hailiutu River, and mass balance equations were employed to estimate groundwater seepage rates along the river using chemical profiles. The hydrograph separation method was used to estimate temporal variations of groundwater discharges to the river. A numerical groundwater model was constructed to simulate groundwater discharges along the river and to analyze effects of water use in the catchment. The simulated seepage rates along the river compare reasonably well with the seepage estimates derived from a chemical profile in 2012. The impacts of human activities (river-water diversion and groundwater abstraction) on the river discharge were analyzed by calculating the differences between the simulated natural groundwater discharge and the measured river discharge. Water use associated with the Hailiutu River increased from 1986 to 1991, reached its highest level from 1992 to 2000, and decreased from 2001 onwards. The reduction of river discharge might have negative impacts on the riparian ecosystem and the water availability for downstream users. The interactions between groundwater and surface water as well as the consequences of human activities should be taken into account when implementing sustainable water resources management in the Hailiutu catchment.

  16. The role of basic health insurance on depression: an epidemiological cohort study of a randomized community sample in Northwest China

    Directory of Open Access Journals (Sweden)

    Tian Donghua

    2012-09-01

    Full Text Available Abstract Background Little research has focused on the relationship between health insurance and mental health in the community. The objective of this study is to determine how the basic health insurance system influences depression in Northwest China. Methods Participants were selected from 32 communities in two northwestern Chinese cities through a three-stage random sampling. Three waves of interviews were completed in April 2006, December 2006, and January 2008. The baseline survey was completed by 4,079 participants. Subsequently, 2,220 participants completed the first follow-up, and 1,888 completed the second follow-up. Depression symptoms were measured by the Center for Epidemiologic Studies Depression Scale (CES-D. Results A total of 40.0% of participants had at least one form of health insurance. The percentages of participants with severe depressive symptoms in the three waves were 21.7%, 22.0%, and 17.6%. Depressive symptoms were found to be more severe among participants without health insurance in the follow-up surveys. After adjusting for confounders, participants without health insurance were found to experience a higher risk of developing severe depressive symptoms than participants with health insurance (7 months: OR, 1.40; 95% CI, 1.09-1.82; p = 0.01; 20 months: OR, 1.89; 95% CI, 1.37-2.61; p  Conclusion A lack of basic health insurance can dramatically increase the risk of depression based on northwestern Chinese community samples.

  17. C:N:P stoichiometry and leaf traits of halophytes in an arid saline environment, northwest China.

    Directory of Open Access Journals (Sweden)

    Lilong Wang

    Full Text Available Salinization is an important and increasingly prevalent issue which has broad and profound effects on plant survival and distribution pattern. To understand the patterns and potential drivers of leaf traits in saline environments, we determined the soil properties, leaf morphological traits (specific leaf area, SLA, and leaf dry matter content, LDMC, leaf chemical traits (leaf carbon, C, nitrogen, N, and phosphorus, P, stoichiometry based on 142 observations collected from 23 sites in an arid saline environment, which is a vulnerable ecosystem in northwest China. We also explored the relationships among leaf traits, the responses of leaf traits, and plant functional groups (herb, woody, and succulent woody to various saline environments. The arid desert halophytes were characterized by lower leaf C and SLA levels, higher N, but stable P and N:P. The leaf morphological traits were correlated significantly with the C, N, and P contents across all observations, but they differed within each functional group. Succulent woody plants had the lowest leaf C and highest leaf N levels among the three functional groups. The growth of halophytes might be more limited by N rather than P in the study area. GLM analysis demonstrated that the soil available nutrients and plant functional groups, but not salinity, were potential drivers of leaf C:N:P stoichiometry in halophytes, whereas species differences accounted for the largest contributions to leaf morphological variations. Our study provides baseline information to facilitate the management and restoration of arid saline desert ecosystem.

  18. C:N:P stoichiometry and leaf traits of halophytes in an arid saline environment, northwest China.

    Science.gov (United States)

    Wang, Lilong; Zhao, Guanxiang; Li, Meng; Zhang, Mingting; Zhang, Lifang; Zhang, Xinfang; An, Lizhe; Xu, Shijian

    2015-01-01

    Salinization is an important and increasingly prevalent issue which has broad and profound effects on plant survival and distribution pattern. To understand the patterns and potential drivers of leaf traits in saline environments, we determined the soil properties, leaf morphological traits (specific leaf area, SLA, and leaf dry matter content, LDMC), leaf chemical traits (leaf carbon, C, nitrogen, N, and phosphorus, P, stoichiometry) based on 142 observations collected from 23 sites in an arid saline environment, which is a vulnerable ecosystem in northwest China. We also explored the relationships among leaf traits, the responses of leaf traits, and plant functional groups (herb, woody, and succulent woody) to various saline environments. The arid desert halophytes were characterized by lower leaf C and SLA levels, higher N, but stable P and N:P. The leaf morphological traits were correlated significantly with the C, N, and P contents across all observations, but they differed within each functional group. Succulent woody plants had the lowest leaf C and highest leaf N levels among the three functional groups. The growth of halophytes might be more limited by N rather than P in the study area. GLM analysis demonstrated that the soil available nutrients and plant functional groups, but not salinity, were potential drivers of leaf C:N:P stoichiometry in halophytes, whereas species differences accounted for the largest contributions to leaf morphological variations. Our study provides baseline information to facilitate the management and restoration of arid saline desert ecosystem.

  19. Phylogenetic Diversity of Ammopiptanthus Rhizobia and Distribution of Rhizobia Associated with Ammopiptanthus mongolicus in Diverse Regions of Northwest China.

    Science.gov (United States)

    Zhao, Liang; Wang, Xinye; Huo, Haibo; Yuan, Guiji; Sun, Yali; Zhang, Dehui; Cao, Ying; Xu, Lin; Wei, Gehong

    2016-07-01

    Aiming to investigate the diversity and distribution of rhizobia associated with Ammopiptanthus, an endangered evergreen legume widely distributed in deserts, we characterized a total of 219 nodule isolates from nine sampling sites in Northwest China with different soil characteristics based upon restriction fragment length polymorphism (RFLP) analysis of 16S ribosomal RNA (rRNA) and symbiotic genes (nodC and nifH). Ten isolates representing different 16S rRNA-RFLP types were selected for further sequence analyses of 16S rRNA and four housekeeping genes. As results, nine genospecies belonging to the genera Ensifer, Neorhizobium, Agrobacterium, Pararhizobium, and Rhizobium could be defined among the isolates. The nodC and nifH phylogenies of 14 isolates representing different symbiotic-RFLP types revealed five lineages linked to Ensifer fredii, Ensifer meliloti, Rhizobium leguminosarum, Mesorhizobium amorphae, and Rhizobium gallicum, which demonstrated the various origins and lateral transfers of symbiotic genes between different genera and species. The rhizobial diversities of Ammopiptanthus mongolicus varied among regions, and the community compositions of rhizobia associated with A. mongolicus were significantly different in wild and cultured fields. Constrained correspondence analysis showed that the distribution of A. mongolicus rhizobia could be explained by available potassium content and that the assembly of symbiotic types was mainly affected by available phosphorus content and carbon-nitrogen ratio.

  20. Groundwater and surface-water interactions and impacts of human activities in the Hailiutu catchment, northwest China

    Science.gov (United States)

    Yang, Zhi; Zhou, Yangxiao; Wenninger, Jochen; Uhlenbrook, Stefan; Wang, Xusheng; Wan, Li

    2017-08-01

    The interactions between groundwater and surface water have been significantly affected by human activities in the semi-arid Hailiutu catchment, northwest China. Several methods were used to investigate the spatial and temporal interactions between groundwater and surface water. Isotopic and chemical analyses of water samples determined that groundwater discharges to the Hailiutu River, and mass balance equations were employed to estimate groundwater seepage rates along the river using chemical profiles. The hydrograph separation method was used to estimate temporal variations of groundwater discharges to the river. A numerical groundwater model was constructed to simulate groundwater discharges along the river and to analyze effects of water use in the catchment. The simulated seepage rates along the river compare reasonably well with the seepage estimates derived from a chemical profile in 2012. The impacts of human activities (river-water diversion and groundwater abstraction) on the river discharge were analyzed by calculating the differences between the simulated natural groundwater discharge and the measured river discharge. Water use associated with the Hailiutu River increased from 1986 to 1991, reached its highest level from 1992 to 2000, and decreased from 2001 onwards. The reduction of river discharge might have negative impacts on the riparian ecosystem and the water availability for downstream users. The interactions between groundwater and surface water as well as the consequences of human activities should be taken into account when implementing sustainable water resources management in the Hailiutu catchment.

  1. Biomass production and carbon sequestration of a short-rotation forest with different poplar clones in northwest China.

    Science.gov (United States)

    Meifang, Yan; Lu, Wang; Honghui, Ren; Xinshi, Zhang

    2017-05-15

    Short Rotation Forestry (SRF) is of interest as producers of biomass for bio-energy, but also as carbon (C) sinks to mitigate CO2 emission. To investigate biomass production and C sequestration of SRF, ecosystem C stock (including C stored in tree biomass, litter and soil), NPP (net primary productivity), heterotrophic respiration (Rh) and NEP (net ecosystem productivity) of three poplar clone plantations were estimated by repeated field sampling in northwest China. Ecosystem C stock (105.62MgCha(-1)) was significantly lower in PB (P. balsamifera) stand than in PD (P. deltoids) and PE (P.×euramericana) stands (Pplantations all acted as C sinks, averagely absorbing 3.45MgCha(-1) during a year. Our results suggest that clone type is a main factor influencing C sequestration capacity of a plantation, along with determining the amount of biomass yield. The success of poplar plantations as a bio-energy resource largely depends on the selection of hybrid varieties. Copyright © 2017. Published by Elsevier B.V.

  2. Comparison between the response of the Northwest Pacific Ocean and the South China Sea to Typhoon Megi (2010)

    Science.gov (United States)

    Li, Zi-Liang; Wen, Ping

    2017-01-01

    The upper-ocean responses to Typhoon Megi (2010) are investigated using data from ARGO floats and the satellite TMI. The experiments are conducted using a three-dimensional Princeton Ocean Model (POM) to assess the storm, which affected the Northwest Pacific Ocean (NWP) and the South China Sea (SCS). Results show that the upwelling and entrainment experiment together account for 93% of the SST anomalies, where typhoon-induced upwelling may cause strong ocean cooling. In addition, the anomalous SST cooling is stronger in the SCS than in the NWP. The most striking feature of the ocean response is the presence of a two-layer inertial wave in the SCS—a feature that is absent in the NWP. The near-inertial oscillations can be generated as typhoon wakes, which have maximum flow velocity in the surface mixed layer and may last for a few days, after the typhoon's passage. Along the typhoon tracks, the horizontal currents in the upper ocean show a series of alternating negative and positive anomalies emanating from the typhoon.

  3. Irrigation water productivity is more influenced by agronomic practice factors than by climatic factors in Hexi Corridor, Northwest China

    Science.gov (United States)

    Li, Xiaolin; Zhang, Xiaotao; Niu, Jun; Tong, Ling; Kang, Shaozhong; Du, Taisheng; Li, Sien; Ding, Risheng

    2016-12-01

    Quantifying the influence of driving factors on irrigation water productivity (IWP) is vital for efficient agricultural water use. This study analyzed contributions of agronomic practice and climatic factors to the changes of IWP, based on the data from 1981 to 2012 in Hexi Corridor, Northwest China. Cobb-Douglas production functions were developed by the partial least squares method and contribution rates of the driving factors were calculated. Results showed that IWP and its driving factors increased during the study period, with different changing patterns. IWP was significantly correlated with the agronomic practice factors, daily mean temperature and solar radiation of the crop growing period. The agronomic practice factors including irrigation, fertilization, agricultural film, and agricultural pesticide contributed 20.6%, 32.8%, 42.3% and 11.1% respectively to the increase of IWP; and the contribution rates of the climatic factors, i.e. daily mean temperature and solar radiation, are ‑0.9% and 0.9%. And the contributions of these factors changed in different sub-periods. It is concluded that agronomic practice factors influenced IWP much more than climatic factors. The improvement of IWP should rely on advanced water-saving technology and application of optimum (need-based) fertilizer, agricultural film and pesticide, ensuring efficient use of agronomic inputs in the study area.

  4. Effect of Nitrogen Management on Yield and Water Use Efficiency of Rainfed Wheat and Maize in Northwest China

    Institute of Scientific and Technical Information of China (English)

    DANG Ting-Hui; CAI Gui-Xin; GUO Sheng-Li; HAO Ming-De; L.K.HENG

    2006-01-01

    A field experiment with four treatments and four replicates in a randomized complete block design was conducted at the Changwu Experimental Station in Changwu County, Shaanxi Province, of Northwest China from 1998 to 2002. The local cropping sequence of wheat, wheat-beans, maize, and wheat over the 4-year period was adopted. A micro-plot study using 15N-labelled fertilizer was carried out to determine the fate of applied N fertilizer in the first year. When N fertilizer was applied wheat (years 1, 2 and 4) and maize (year 3) grain yield increased significantly (P < 0.05) (> 30%), with no significant yield differences in normal rainfall years (Years 1, 2 and 3) for N application at the commonly application rate and at 2/3 of this rate. Grain yield of wheat varied greatly between years, mainly due to variation in annual rainfall.Results of 15N studies on wheat showed that plants recovered 36.6%-38.4% of the N applied, the N remained in soil (0-40cm) ranged from 29.2% to 33.6%, and unaccounted-for N was 29.5%-34.2%. The following crop (wheat) recovered 2.1%-2.8% of the residual N from N applied to the previous wheat crop with recovery generally decreasing in the subsequent three crops (beans, maize and wheat).

  5. The Vulnerability of Water Resources in Northwest China%中国西北水资源的脆弱性

    Institute of Scientific and Technical Information of China (English)

    刘春蓁

    2003-01-01

    The vulnerability of water resources in Northwest China were described in terms of the sensitivity and adaptability of water resource systems effected by climate change and human activities. Most measures that reduce the vulnerability are closely linked with decreasing the sensitivity of climate change or human activity. In other words, the interaction of climate factors and human activity may either exacerbate or mitigate the vulnerability of water resources. Studying both positive and negative events in terms of sustainable utilization of water resources in the past, may establish the sound strategic base in regulating further human activity. The knowledge and correct awareness of recent and future tendencies of hydro-climatic condition may serve as an imperative scientific base for taking such actions as: 1) undertaking structural and non-structural (e.g., policy, law, and forecasting) measures in a reasonable way; 2) coordinating and allocating both differences of time and space between inflow water and water use and between water yield area and water assumption area as well.

  6. Multiple cooling episodes in the Central Tarim (Northwest China) revealed by apatite fission track analysis and vitrinite reflectance data

    Science.gov (United States)

    Chang, Jian; Qiu, Nansheng; Song, Xinying; Li, Huili

    2016-06-01

    Apatite fission track and vitrinite reflectance are integrated for the first time to study the cooling history in the Central Tarim, northwest China. The paleo-temperature profiles from vitrinite reflectance data of the Z1 and Z11 wells showed a linear relationship with depth, suggesting an approximately 24.8 °C/km paleo-geothermal gradient and 2700-3900 m of erosion during the Early Mesozoic. The measured apatite fission track ages from well Z2 in the Central Tarim range from 39 to 159 Ma and effectively record the Meso-Cenozoic cooling events that occurred in Central Tarim. Moreover, two cooling events at 190-140 Ma in the Early Jurassic-Early Cretaceous and 80-45 Ma in the Late Cretaceous-Paleocene revealed by measured AFT data and thermal modeling results are related to the collisions of the Qiangtang-Lhasa terranes and the Greater India Plate with the southern margin of the Eurasian Plate, respectively. This study provides new insights into the tectonic evolution of the Tarim Basin (and more broadly Central Asia) and for hydrocarbon generation and exploration in the Central Tarim.

  7. Molecular detection, identification and phylogenetic inference of Leishmania spp. in some desert lizards from Northwest China by using internal transcribed spacer 1 (ITS1) sequences.

    Science.gov (United States)

    Zhang, Jun-Rong; Guo, Xian-Guang; Liu, Jin-Long; Zhou, Tian-He; Gong, Xiong; Chen, Da-Li; Chen, Jian-Ping

    2016-10-01

    Leishmaniasis caused by Leishmania is still endemic in Northwest China. It has been thought that reptiles could be a reservoir for mammalian leishmaniasis. However, data are still scarce on natural infection of lizards with Leishmania spp. in China. The present study deals with detection, identification and phylogenetic inference of Leishmania parasites at species and intraspecies levels isolated from six desert lizard species from 10 geographical locations in Northwest China using amplification and sequencing of ITS-rDNA. In total, 83 haplotypes were found among 137 ITS1 sequences obtained from up to 64.6% of all captured lizards. Representative sequences of Leishmania available in GenBank were compiled for comparison with the obtained haplotypes. Tree-based species delimitation was achieved by using Bayesian phylogenitc analyses and maximum parsimony approach. Phylogenetic trees congruently supported that the haplotypes were found to belong to three Leishmania species including L. (sauroleishmania) sp., Leishmania tropica and Leishmania donovani complex. A network approach revealed paraphyletic populations of L. (sauroleishmania) sp. and L. tropica at intraspecies level regarding geographical origin and low host specificity. Chinese L. tropica from lizards showed significant heterogeneity as the obtained haplotypes were distributed in different clusters from other countries. Common ancestry was observed between some sequences of L. tropica from lizards and other sequence types from clinical samples from other countries. This may lend support to the potential reservoir role of lizards for human leishmaniasis. Our results appear to be the first molecular evidence for natural infection of lizards in Northwest China with reptilian Leishmania and mammalian Leishmania species. Desert lizards may be considered as putative reservoir hosts for Leishmania in China. Further studies on persistence of the Leishmania parasites in lizards and sandflies are recommended for the

  8. More Girls Going to School Raises Hope for Women in Northwest China

    Institute of Scientific and Technical Information of China (English)

    JANE SHAW

    1994-01-01

    THE main difficulty developing countries have faced in making primary education universal is its education of girls. In Gansu and Qinghai provinces and the Ningxia Hui Autonomous Region of China, experimental schools for girls sponsored by education workers have seen inspiring results. In 1993, 96.4 percent of girls continued their schooling. According to 1990 statistics, more than 180 million Chinese were illiterate; two-thirds of them were women. Also, of children aged 7-11 who hadn’t yet gone to school, girls accounted for 81 percent. Currently, provinces and autonomous regions with the lowest enrollment rate for girls are all located in remote, poor or

  9. Alpine Ecosystems of Northwest Yunnan, China: an Initial Assessment for Conservation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Implementing conservation actions on-the-ground is not a straightforward process,especially when faced with high scientific uncertainty due to limited available information. This is especially acute in regions of the world that harbor many unique species that have not been well studied, such as the alpine zone of the Hengduan Mountains of Northwest Yunnan (NWY), a global biodiversity hotspot and site of The Nature Conservancy's Yunnan Great Rivers Project. We conducted a quantitative, but rapid regional-level assessment of the alpine flora across NWY to provide a broad-based understanding of local and regional patterns of the alpine flora, the first large-scale analysis of alpine biodiversity patterns in this region. Multivariate analyses were used to classify the major plant community types and link community patterns to habitat variables. Our analysis indicated that most species had small distributions and/or small population sizes. Strong patterns emerged with higher diversity in the more northern mountains, but beta diversity was high, averaging only 10% among sites. The ordinations indicated that elevation and geographic location were the dominant environmental gradients underlying the differences in the species composition among communities. The high beta diversity across the alpine of these mountains implies that conservation strategies ultimately will require the protection of large numbers of species over a large geographical area. However, prioritization should be given to areas where potential payoffs are greatest. Sites with high species richness also have a greater number of endemic species, and, by focusing efforts on these sites, conservation investments would be maximized by protecting the greatest number of unique species.

  10. Evaluating Impacts of Industrial Transformation on Water Consumption in the Heihe River Basin of Northwest China

    Directory of Open Access Journals (Sweden)

    Feng Wu

    2014-11-01

    Full Text Available Growing water scarcity is one of the central challenges for sustainability in China, given its burgeoning industry and huge population, especially in the arid and semi-arid inland river basin where precipitation is very limited. Industrial transformation is an important engine of economic growth, which is required to be implemented by governments at all levels in China. Economic models have generally been applied to evaluate the effects of economic policy change (e.g., industrial transformation or adjustment of price on the allocation of production factors. The computable general equilibrium (CGE model is an effective tool to reallocate the primary factors across sectors for different industrial transformation scenarios. In this research, we first briefly introduced the principles and structure of the CGE model, which embeds water resources as a primary factor of production. Then we chose Zhangye as an example to evaluate the impacts of industrial transformation on water consumption under three designed scenarios with the water-embedded CGE model. Simulation results showed that there will be considerable water saving benefit from industrial transformation when the output value of secondary industry and tertiary industry increases and the contribution of the planting sector to the total output value decreases. Finally, we put forward a scheme that can improve water utilization efficiency in policy options.

  11. Evidence for UHP metamor phism of eclogites from the Altun Mountains

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Ultrahigh pressure (UHP) metamorphism refers to metamorphism that has occurred at pressures for the stability of coesite. The polycrystalline quartz inclusions showing the characteristic texture within garnets of eclogites indicates the pre-existence of coesites under the peak metamorphic condition. The unusual exsolution textures in ompacites and apatites, and the pressure estimations of phengite-bearing eciogites have been taken to provide further proof of eclogite formation under the UHP conditions.Combined with the fact that coesites have been observed in country rocks of eclogites in North Qaidam Mountains, another UHP metamorphic belt cut by the large-scale strikeslip fault in the AItun-North Qaidam area of China is confirmed.``

  12. Groundwater Quality in Jingyuan County, a Semi-Humid Area in Northwest China

    Directory of Open Access Journals (Sweden)

    Wu Jianhua

    2011-01-01

    Full Text Available Groundwater quality assessment is an essential study which plays an important role in the rational development and utilization of groundwater in any part of the world. In the study, groundwater qualities in Jingyuan County, in Ningxia, China were assessed with entropy weighted water quality index method. In the assessment, 12 hydrochemical parameters including chloride, sulphate, sodium, iron, pH, total dissolved solid (TDS, total hardness (TH, nitrate, ammonia, nitrogen, fluoride, iodine and nitrite were selected. The assessment results show that the concentrations of iodine, TH, iron and TDS are the most influencing parameters affecting the groundwater quality. The assessment results are rational and are in consistency with the results of filed investigation of which both indicates the groundwater in Jingyuan County is fit for drinking.

  13. Contribution of Root Respiration to Total Soil Respiration in a Cotton Field of Northwest China

    Institute of Scientific and Technical Information of China (English)

    ZHAO Zhi-Min; ZHAO Cheng-Yi; Y.YILIHAMU; LI Ju-Yan; LI Jun

    2013-01-01

    To measure the contribution of root respiration (Rr) to total soil respiration (Rt) in arid cotton fields,eighteen plots,nine for girdling and nine control,were built in an arid cotton field in the Aksu National Experimental Station of Oasis Farmland Ecosystem,Xinjiang of China.Given the difference of soil respiration between girdled plots and non-girdled control plots,the components of soil respiration,root respiration (Rr) and respiration originating from decomposition (Rd) were divided.The temperature sensitivities of Rr and Rd were analyzed,respectively.The results showed that the average contribution of Rr to Rt in arid cotton field was about 32% during the study period.The temperature-response curve of Rr differed from that of Rd.The dynamic variation of Rd was more related to the change of soil temperature as compared to Rr.Rr and Rd had different responses to the variation of environment,and thus new models capable of differentiating between Rr and Rd are needed for evaluating the different factors controlling these two components of soil respiration in arid cotton field.

  14. Characteristics of stemflow for sand-fixed shrubs in Mu Us sandy land, Northwest China

    Institute of Scientific and Technical Information of China (English)

    YANG ZhiPeng; LI XiaoYan; LIU LianYou; WU JianJun; HASI Eerdun; SUN YongLiang

    2008-01-01

    Little work has been done on stemflow for desert shrubs in China. This study measured stemflow in two shrubs of Salix psammophila C. Wang et Chang Y. Yang and Artemisia sphaerocephala Krasch in Mu Us sandy land and established a relationship between stemflow and canopy characteristics, rainfall amount and intensity. During the experimental period, the amount of stemflow for S. psammophila and A. sphaerocephala accounted for 7.6% and 2.7% of the gross rainfall respectively. Statistical analysis showed that there was a significant positive linear correlation between rainfall and stemflow for the two shrubs; while the relationship between stemflow percentage and rainfall suggested that there existed a rainfall depth threshold of 3-5 mm for S. psammophila and 5-7 mm for A. sphaerocephala. Stemflow percentage positively increased with rainfall depth increasing before the rainfall depth threshold values had been reached but showed stability after the threshold. A stepwise regression analysis suggested that the shrubs with more branches, larger crown volume and smaller branch angle inclination tended to collect more volumes of stemflow. Moreover, stemflow amount and percentage increased with the maximum rain intensity increasing in 10 minutes (/10) and the stemflow percentage tended to increase quickly with /10 when it was less than 3.0 mm h-1 for S. psammophila and 2.0 mm h-1 for A. sphaero-cephala, and then showed stable trend with increasing of/10.

  15. Upper mantle convection beneath northwest China and its adjacent region driven by density anomaly

    Institute of Scientific and Technical Information of China (English)

    XU Ping; FU Rong-shan; HUANG Jian-ping; ZHAXian-jie; DAI Zhi-yang

    2006-01-01

    We assume that the density anomalies, which are transformed from seismic tomography data, are corresponding to temperature distribution in a convective mantle. We take density anomalies as the driving force for mantle convec tion and solve the basic equation with given boundary conditions in a wave-number domain by using the FFT arithmetic. Using the physical model of upper mantle convection and the seismic tomography data supplied by XU et al, we calculated upper mantle convection beneath northwestern China and adjacent region. The flow patterns in the upper mantle show that there are upward and divergent flows in the basin regions, such as Tarim, Qaidam,Junggar and Kazakhstan, where the lithosphere is thin. There are downward and convergent flows in the mountain regions,such as Tianshan, Kunlun and Qilian, where the lithosphere is thick. In addition, because of the divergent flow under the Tarim Basin the upper mantle material in this region is driven southward to the north part of Tibetan Plateau and northward to Tianshan Mountain. Maybe, it is one of the reasons for the recent uplift of the Tianshan Mountain.

  16. The effectiveness assessment of gas accumulation processes in Kuqa depression,Tarim Basin,Northwest China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The effectiveness of gas accumulation processes is controlled by several main geological factors in-cluding charging force,features of gas conduit,sealing properties of caprock,etc. Based on the analysis and statistics of the large-medium size gas accumulations in China,the main parameters,in-cluding the excess pressure difference between the source rock and reservoir bed,the area coefficient of the gas conduit,and the thickness or displacement pressure of caprock,and the criteria for the as-sessment of gas accumulation processes have been established. Using the parameters and the criteria above,the effectiveness of gas accumulation processes in the Kuqa depression was quantitatively evaluated. By integrating the parameters of the excess pressure difference between the source rock and reservoir bed,the area coefficient of fault conduit system,and the caprock thickness in gas charging period,a comprehensive assessment of the effectiveness of gas accumulation in the Kuqa depression has been made. The result reveals that the Tubei-Dawan area,the Central Kelasu area and the Dongqiu-Dina area are three highly-effective areas for gas accumulation in the Kuqa depression.

  17. Speciation, sources, and risk assessment of heavy metals in suburban vegetable garden soil in Xianyang City, Northwest China

    Science.gov (United States)

    Wang, Lijun; Tao, Wendong; Smardon, Richard C.; Xu, Xue; Lu, Xinwei

    2017-07-01

    Intensive anthropogenic activities can lead to soil heavy metal contamination resulting in potential risks to the environment and to human health. To reveal the concentrations, speciation, sources, pollution level, and ecological risk of heavy metals in vegetable garden soil, a total of 136 soil samples were collected from three vegetable production fields in the suburbs of Xianyang City, Northwest China. These samples were analyzed by inductively coupled plasma- atomic emission spectrometry and atomic fluorescence spectrometry. The results showed that the mean concentrations of Cd, Co, Cu, Mn, Pb, Zn, and Hg in vegetable garden soil were higher than the corresponding soil element background values of Shaanxi Province. The heavy metals studied in vegetable garden soil were primarily found in the residual fraction, averaging from 31.26% (Pb) to 90.23% (Cr). Considering the non-residual fractions, the mobility or potential risk was in the order of Pb (68.74%)>Co (60.54%)>Mn (59.28%) >Cd (53.54%) ≫Ni (23.36%) >Zn (22.73%)>Cu (14.93%)>V (11.81%)>Cr (9.78%). Cr, Mn, Ni, V, and As in the studied soil were related to soilforming parent materials, while Cu, Hg, Zn, Cd, Co, and Pb were associated with the application of plastic films, fertilizers, and pesticides, as well as traffic emissions and industrial fumes. Cr, Ni, V, and As presented low contamination levels, whereas Co, Cu, Mn, Pb, and Zn levels were moderate, and Cd and Hg were high. Ecological risk was low for Co, Cr, Cu, Mn, Pb, Zn, and As, with high risk observed for Cd and Hg. The overall pollution level and ecological risk of these heavy metals were high.

  18. Potential transport pathways of dust emanating from the playa of Ebinur Lake, Xinjiang, in arid northwest China

    Science.gov (United States)

    Ge, Yongxiao; Abuduwaili, Jilili; Ma, Long; Wu, Na; Liu, Dongwei

    2016-09-01

    In this paper, the HYSPLIT model, driven with reanalysis meteorological data from 1978 to 2013, was used to understand the potential transport characteristics of dust and salt dust emanating from the playa of Ebinur Lake in arid northwest China. Daily air parcel trajectories were computed forward for 8 days from an origin centered over Ebinur Lake at 100 m above ground level. Air parcel trajectory density plots were mapped for seven levels: 0-100 m agl., 100-500 m agl., 500-1000 m agl., 1000-1500 m agl., 1500-2000 m agl., 2000-3000 m agl., and 3000-5000 m agl. These show that potential dust transport pathways have clear seasonal differentiation. The potential transport distance of dust and salt dust is greatest in spring and summer. In autumn and winter, the potential transport of the high-density air trajectory is below 1000 m traveling a shorter distance. Potential dust transport pathways showed notifying directivity in different seasons and heights. Southeast in spring and summer, and north to northeast in autumn and winter are the two main potential transport channels of dust and salt dust. Accordingly, dust and salt dust from the playa of Ebinur Lake may influence the atmospheric processes and biogeochemical cycles of a vast region. The main area of influence of dust and salt dust is close to the source area, and will significantly accelerate the melting of snow and ice in the Tianshan Mountains. This highlights the urgent need to combine remote sensing, isotope and other methods to further research the transport characteristics of dust and salt dust from the playa of the Ebinur Lake.

  19. Responses of Vegetation Growth to Climatic Factors in Shule River Basin in Northwest China: A Panel Analysis

    Directory of Open Access Journals (Sweden)

    Jinghui Qi

    2017-03-01

    Full Text Available The vegetation response to climatic factors is a hot topic in global change research. However, research on vegetation in Shule River Basin, which is a typical arid region in northwest China, is still limited, especially at micro scale. On the basis of Moderate-resolution Imaging Spectroradiometer (MODIS Normalized Difference Vegetation Index (NDVI data and daily meteorological data, employing panel data models and other mathematical models, the aim of this paper is to reveal the interactive relationship between vegetation variation and climatic factors in Shule River Basin. Results show that there is a widespread greening trend in the whole basin during 2000–2015, and 80.28% of greening areas (areas with vegetation improvement are distributed over upstream region, but the maximum vegetation variation appears in downstream area. The effects of climate change on NDVI lag about half to one month. The parameters estimated using panel data models indicate that precipitation and accumulated temperature have positive contribution to NDVI. With every 1-mm increase in rainfall, NDVI increases by around 0.223‰ in upstream area and 0.6‰ in downstream area. With every 1-°C increase in accumulated temperature, NDVI increases by around 0.241‰ in upstream area and 0.174‰ in downstream area. Responses of NDVI to climatic factors are more sensitive when these factors are limiting than when they are not limiting. NDVI variation has performance in two seasonal and inter-annual directions, and the range of seasonal change is far more than that of inter-annual change. The inverted U-shaped curve of the variable intercepts reflects the seasonal change. Our results might provide some scientific basis for the comprehensive basin management.

  20. Origin and assessment of groundwater pollution and associated health risk: a case study in an industrial park, northwest China.

    Science.gov (United States)

    Li, Peiyue; Wu, Jianhua; Qian, Hui; Lyu, Xinsheng; Liu, Hongwei

    2014-08-01

    Groundwater quality which relates closely to human health has become as important as its quantity due to the demand for safe water. In the present study, an entropy-weighted fuzzy water quality index (WQI) has been proposed for performing groundwater quality assessment in and around an industrial park, northwest China, where domestic water requirements are solely met by groundwater. The human health risk was assessed with the model recommended by the United States Environmental Protection Agency. In addition, the sources of major ions and main contaminants were also analyzed. The study shows that groundwater in the study area has been contaminated conjunctively by natural processes and industrial and agricultural activities. Nitrate, manganese (Mn), fluoride, total dissolved solids, total hardness and sulfate are major contaminants influencing groundwater quality. Nitrate and heavy metals such as Mn are mainly affected by human agricultural activities and industrial production, while other contaminants are mainly originated from mineral weathering and water-rock interactions. The results of water quality assessment suggest that half of the groundwater samples collected are of medium quality thus require pretreatment before human consumption. The mean health risk caused by the consumption of contaminated groundwater in the area is 8.42 × 10(-5) per year which surpasses the maximum acceptable level (5 × 10(-5) per year) recommended by the International Commission on Radiologic Protection. The entropy-weighted fuzzy WQI proposed in this study can not only assign proper weights to parameters but also treat uncertainties associated with water quality classification. This study will be of interest to international environmentalists and hydrogeologists. It will also be useful in regional groundwater management and protection.

  1. Hydrological Impacts of Land Use Change and Climate Variability in the Headwater Region of the Heihe River Basin, Northwest China.

    Directory of Open Access Journals (Sweden)

    Ling Zhang

    Full Text Available Land use change and climate variability are two key factors impacting watershed hydrology, which is strongly related to the availability of water resources and the sustainability of local ecosystems. This study assessed separate and combined hydrological impacts of land use change and climate variability in the headwater region of a typical arid inland river basin, known as the Heihe River Basin, northwest China, in the recent past (1995-2014 and near future (2015-2024, by combining two land use models (i.e., Markov chain model and Dyna-CLUE with a hydrological model (i.e., SWAT. The potential impacts in the near future were explored using projected land use patterns and hypothetical climate scenarios established on the basis of analyzing long-term climatic observations. Land use changes in the recent past are dominated by the expansion of grassland and a decrease in farmland; meanwhile the climate develops with a wetting and warming trend. Land use changes in this period induce slight reductions in surface runoff, groundwater discharge and streamflow whereas climate changes produce pronounced increases in them. The joint hydrological impacts are similar to those solely induced by climate changes. Spatially, both the effects of land use change and climate variability vary with the sub-basin. The influences of land use changes are more identifiable in some sub-basins, compared with the basin-wide impacts. In the near future, climate changes tend to affect the hydrological regimes much more prominently than land use changes, leading to significant increases in all hydrological components. Nevertheless, the role of land use change should not be overlooked, especially if the climate becomes drier in the future, as in this case it may magnify the hydrological responses.

  2. [Effects of different drip irrigation modes on root distribution of wine grape 'Cabernet Sauvignon' in desert area of Northwest China].

    Science.gov (United States)

    Mao, Juan; Chen, Bai-Hong; Cao, Jian-Dong; Wang, Li-Jun; Wang, Hai; Wang, Yan-Xiu

    2013-11-01

    To study the effects of different drip irrigation modes on the wine grape root distribution is the basis of formulating fertilization, irrigation, and over-wintering management practices for wine grape. Taking the wine grape "Cabernet Sauvignon" as test material, this paper studied the effects of different water-saving irrigation modes (drip irrigation under straw mulching, drip irrigation under plastic mulching, double-tube drip irrigation, and single-tube drip irrigation) on the root distribution of wine grape in the desert area of Northwest China, with the conventional furrow irrigation as the control. The root system of the "Cabernet Sauvignon" was distributed from 0 to 70 cm vertically, and from 0 to 120 cm horizontally. With double-tube drip irrigation, the root amount was the largest (138.3 roots per unit profile), but the root vertical distribution scope was narrowed by 20 cm, as compared to the control. Drip irrigation with straw mulching increased the root amount significantly, and increased the root horizontal distribution scope by 9.1%, as compared to the control. No significant difference was observed in the root number and root horizontal distribution scope between the drip irrigation under plastic mulching and the control, but the root vertical distribution scope with the drip irrigation under plastic mulching decreased by 20 cm. Single-tube drip irrigation increased the root number significantly, but had lesser effects on the root vertical or horizontal distribution, as compared to the conventional irrigation. It was suggested that the drip irrigation under straw mulching could be the best water-saving practice for the wine grape "Cabernet Sauvignon" in the study area.

  3. Improved cloud mask algorithm for FY-3A/VIRR data over the northwest region of China

    Science.gov (United States)

    Wang, X.; Li, W.; Zhu, Y.; Zhao, B.

    2013-03-01

    The existence of various land surfaces always leads to more difficulties in cloud detection based on satellite observations, especially over bright surfaces such as snow and deserts. To improve the cloud mask result over complex terrain, an unbiased, daytime cloud detection algorithm for the Visible and InfRared Radiometer (VIRR) on board the Chinese FengYun-3A polar-orbiting meteorological satellite is applied over the northwest region of China. The algorithm refers to the concept of the clear confidence level from Moderate Resolution Imaging Spectroradiometer (MODIS) and the unbiased structure of the CLoud and Aerosol Unbiased Decision Intellectual Algorithm (CLAUDIA). Six main channels of VIRR centered at the wavelengths of 0.455, 0.63, 0.865, 1.595, 1.36, and 10.8 μm are designed to estimate the degree of a pixel's cloud contamination judged by the clear confidence level. Based on the statistical data set during four months (January, April, July, and October) in 2010, seasonal thresholds are applied to improve the accuracy of the cloud detection results. Flags depicting snow and water are also generated by the specific threshold tests for special surfaces. As shown in image inspections, the cloud detection results over snow and deserts, adopting the proposed scheme, exhibit better correlations with true-color images than the VIRR official cloud mask results do. The performance of the proposed algorithm has been evaluated in detail for four seasons in 2011, using cloud mask products from MODIS and the ground-based observations. The evaluation is based on, overall, 47 scenes collocated with MODIS and 96 individual matchups between VIRR and the ground-based observations from two weather stations located in the research region. The quantitative validations suggest that the estimations of clear-sky regions have been greatly improved by the proposed algorithm, while a poor identification of the cirrus clouds occurs over deserts.

  4. Improved cloud mask algorithm for FY-3A/VIRR data over the northwest region of China

    Directory of Open Access Journals (Sweden)

    X. Wang

    2013-03-01

    Full Text Available The existence of various land surfaces always leads to more difficulties in cloud detection based on satellite observations, especially over bright surfaces such as snow and deserts. To improve the cloud mask result over complex terrain, an unbiased, daytime cloud detection algorithm for the Visible and InfRared Radiometer (VIRR on board the Chinese FengYun-3A polar-orbiting meteorological satellite is applied over the northwest region of China. The algorithm refers to the concept of the clear confidence level from Moderate Resolution Imaging Spectroradiometer (MODIS and the unbiased structure of the CLoud and Aerosol Unbiased Decision Intellectual Algorithm (CLAUDIA. Six main channels of VIRR centered at the wavelengths of 0.455, 0.63, 0.865, 1.595, 1.36, and 10.8 μm are designed to estimate the degree of a pixel's cloud contamination judged by the clear confidence level. Based on the statistical data set during four months (January, April, July, and October in 2010, seasonal thresholds are applied to improve the accuracy of the cloud detection results. Flags depicting snow and water are also generated by the specific threshold tests for special surfaces. As shown in image inspections, the cloud detection results over snow and deserts, adopting the proposed scheme, exhibit better correlations with true-color images than the VIRR official cloud mask results do. The performance of the proposed algorithm has been evaluated in detail for four seasons in 2011, using cloud mask products from MODIS and the ground-based observations. The evaluation is based on, overall, 47 scenes collocated with MODIS and 96 individual matchups between VIRR and the ground-based observations from two weather stations located in the research region. The quantitative validations suggest that the estimations of clear-sky regions have been greatly improved by the proposed algorithm, while a poor identification of the cirrus clouds occurs over deserts.

  5. Post-Orogenic Granites in Pingwu Region, Northwest Sichuan: Evidence for North China Block and Yangtze Block Collision during Triassic

    Institute of Scientific and Technical Information of China (English)

    Pei Xianzhi; Li Zuochen; Ding Saping; Feng Jianyun; Li Ruibao; Sun Yu; Zhang Yafeng; Liu Zhanqing

    2009-01-01

    The Nanyili (南一里), Laohegou (老河沟), and Shaiziyan (筛子岩) granitic intrusions are located in the southern margin of the Bikou (碧口) block in Pingwu (平武) area, Northwest Sichuan (四川). The petrography and geochemical characteristics of the granitic intrusions as well as their source and tectonic settings are reported and discussed in this article. The Laohegou and Shaiziyan granites are with high SiO2 (69.89 wt.%-73.05 wt.%) and Al2O3 contents, and A/CNK=1.04-1.12. They are typi-cal strongly peraluminous granites, with supersaturation in Al and Si. The abundance of ∑REE varies in the range of (33.13-89.12)×106. The rocks show an LREE enrichment pattern and obvious Eu nega-tive anomaly. The trace element geochemistry is characterized evidently by a negative anomaly of Ta, Nb, Ti, etc. and a positive anomaly of Rb, Ba, Sr, etc.. Zircons of the Nanyili granite have higher Th/U ratios, and their CL images have internal oscillatory zoning, suggesting that the zircons of the samples are igneous in origin. The LA ICP-MS zircon U-Pb isotopic concordia diagram yields an age of 223.1±2.6 Ma (MSWD=1.4), which indicates that the granodiorite intrusions formed in the early Late Triassic. The Nanyili, Laohegou, and Shaiziyan granites have the characteristics of post-eollisional granites and are regarded as post-orogenic granites. Thus, the granite intrusions are interpreted as syn-collisional granites that resulted from the crustal thickening caused by the collisions between the North China plate and the Yangtze plate during the Indosinian. The granitic intrusions formed in a transitional environment from syn- (compres-slonal environment) to post-collision (extensionalenvironment).

  6. Improved cloud mask algorithm for FY-3A/VIRR data over the northwest region of China

    Directory of Open Access Journals (Sweden)

    X. Wang

    2012-11-01

    Full Text Available The existence of various land surfaces has always been a difficult problem for researchers who study cloud detection using satellite observations, especially over bright surfaces such as snow and desert. To improve the cloud mask result over complex terrain, an unbiased daytime cloud detection algorithm for the Visible and InfRared Radiometer (VIRR on board the Chinese FengYun-3A polar-orbiting meteorological satellite is applied over the northwest region of China. Based on the statistical seasonal threshold tests, the algorithm consists of six main channels centered on the wavelengths of 0.63, 0.865, 10.8, 1.595, 0.455, and 1.36 μm. The combination of the unbiased algorithm and the specific threshold tests for special surfaces has effectively improved the cloud mask results over complex terrain and decreased the false identifications of clouds. The visual images over snow and desert adopting the proposed scheme exhibit better correlations with true-color images than do the VIRR official cloud mask results. The validation with the Moderate Resolution Imaging Spectroradiometer (MODIS cloud mask product shows that the probability of detection for clear-sky regions over snow of the new scheme has increased nearly five times over the official method, and the false-alarm ratio for cloudy areas over desert has reduced by half compared with the official result. With regard to comparisons between ground measurements and cloud mask results, this approach also provides acceptable correspondence with the ground observations except for some cases, which are mainly obscured by cirrus clouds.

  7. Validation of MODIS and Deep Blue aerosol optical depth retrievals in an arid/semi-arid region of northwest China

    Institute of Scientific and Technical Information of China (English)

    Xia Li; Xiangao Xia; Shengli Wang; Jietai Mao; Yan Liu

    2012-01-01

    The global aerosol optical depth (AOD or τ) has been retrieved using the Dark Target algorithm (the C004 and C005 products) and the Deep Blue algorithm (DB product).Few validations have thus far been performed in arid/semi-arid regions,especially in northwest China.The ground-based remote sensing of AOD from sun photometers at four sites in Xinjiang during the years 2002-2003 is used to validate aerosol products,including C004,C005 and DB of the Moderate Resolution Imaging Spectroradiometer (MODIS).The results show substantial improvement in the C005 aerosol product over the C004 product.The average correlation coefficient of regression with ground measurements increased from 0.59 to 0.69,and the average offset decreased from 0.28 to 0.13.The slopes of the linear regressions tended to be close to unity.The percentage of AODs falling within the retrieval errors of 30% (or △τ =±0.1 ± 0.2τ)increased from 16.1% to 45.6%.The best retrievals are obtained over an oasis region,whereas the worst are obtained over urban areas.Both the MODIS C004 and C005 products overestimate AOD,which is likely related to improper assumptions of the aerosol model and of the estimation of surface reflectance.An encouraging result has been derived with regard to validation of the DB AOD.Overall,the average offset,slope and correlation coefficient of regression with sun-photometer measurements are -0.04,0.88 and 0.85,respectively.Approximately 73% of the DB AOD retrievals fall within the expected error of 30%.Underestimation of the AOD by the DB products is observed.The aerosol model and estimations of surface reflectance in this region require further improvements.

  8. Relationship between species richness and biomass on environmental gradient in natural forest communities on Mt. Xiaolongshan, northwest China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    We analyzed the relationship between species richness and biomass in natural forest communities at two similar sites on Mt. Xiaoiongshan, northwest China. At both sites, a wide range of tree layer biomass levels was available by local biomass estima-tion models. In order to identify underlying mechanism of the species richness-biomass relationship, we included different water resource levels and number of individuals in each plot in our analysis. We sampled 15 and 20 plots (20 m x 20 m), respectively, at both two sites. These plots were sampled equally on the sunny slope and the shady slope. Species richness, number of individuals of each species and diameter at breast height (DBH) as a substitute of biomass of tree layer were recorded in each sample. At one site,the relationship between species richness and biomass was significant on the sunny slope, and this relationship disappeared on the shady slope due to more environmental factors. The relations between species richness and number of individuals and between num-ber of individuals and biomass paralleled the species richness-biomass relation on both slopes. The difference in number of individu-als-biomass relationships on the sunny slope and the shady slope revealed "interspecific competitive exclusion" even though the species richness-biomass relationships were not hump-shaped. At the other site, species richness was not related to biomass or to number of individuals. Our study demonstrated the importance of environmental stress and succession of community in the under-standing of species diversity-productivity patterns.

  9. Assessing the changes in land use and ecosystem services in an oasis agricultural region of Yanqi Basin, Northwest China.

    Science.gov (United States)

    Wang, Shuixian; Wu, Bin; Yang, Pengnian

    2014-12-01

    The Yanqi Basin, one of the most productive agricultural areas, has a high population density in Xinjiang, Northwest China. Land use changes, mainly driven by oasis expansion, significantly impact ecosystem services and functions, but these effects are difficult to quantify. The valuation of ecosystem services is important to clarify the ecological and environmental changes caused by agriculturalization of oasis. This study aimed to investigate variations in ecosystem services in response to land use changes during oasis agricultural expansion activities in the Yanqi Basin from 1964 to 2009. The methods used were based on formula of ecosystem service value (ESV) and ESV coefficients. Satellite data were combined with the ESV coefficients to quantify land use changes and ecosystem service changes in the study area. Sensitivity analysis determined the effect of manipulating the coefficients on the estimated values. The results show that the total ESVs in the Yanqi Basin were $1,674, $1,692, $1,471, $1,732, and $1,603 million in 1964, 1973, 1989, 1999, and 2009, respectively. The net deline in ESV was $71 million in the past 46 years, but the ESVs of each types of landscape changed significantly. The aggregated ESVs of water areas and wetlands were approximately 80 % of the total ESV. Water supply and waste treatment were the two largest service functions and contributed approximately 65 % of the total ESV. The estimated ESVs in this study were elastic with respect to the value coefficients. Therefore, the estimations were robust in spite of uncertainties on the value coefficients. These significant changes in land use occur within the entire basin over the study period. These changes cause environmental problems, such as land degradation, vegetation degeneracy, and changes in aquatic environment.

  10. Hydrological Impacts of Land Use Change and Climate Variability in the Headwater Region of the Heihe River Basin, Northwest China.

    Science.gov (United States)

    Zhang, Ling; Nan, Zhuotong; Xu, Yi; Li, Shuo

    2016-01-01

    Land use change and climate variability are two key factors impacting watershed hydrology, which is strongly related to the availability of water resources and the sustainability of local ecosystems. This study assessed separate and combined hydrological impacts of land use change and climate variability in the headwater region of a typical arid inland river basin, known as the Heihe River Basin, northwest China, in the recent past (1995-2014) and near future (2015-2024), by combining two land use models (i.e., Markov chain model and Dyna-CLUE) with a hydrological model (i.e., SWAT). The potential impacts in the near future were explored using projected land use patterns and hypothetical climate scenarios established on the basis of analyzing long-term climatic observations. Land use changes in the recent past are dominated by the expansion of grassland and a decrease in farmland; meanwhile the climate develops with a wetting and warming trend. Land use changes in this period induce slight reductions in surface runoff, groundwater discharge and streamflow whereas climate changes produce pronounced increases in them. The joint hydrological impacts are similar to those solely induced by climate changes. Spatially, both the effects of land use change and climate variability vary with the sub-basin. The influences of land use changes are more identifiable in some sub-basins, compared with the basin-wide impacts. In the near future, climate changes tend to affect the hydrological regimes much more prominently than land use changes, leading to significant increases in all hydrological components. Nevertheless, the role of land use change should not be overlooked, especially if the climate becomes drier in the future, as in this case it may magnify the hydrological responses.

  11. An Assessment of Storage Terms in the Surface Energy Balance of a Subalpine Meadow in Northwest China

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The heat storage terms in the soil-vegetation-atmosphere system may play an important role in the surface energy budget.In this paper,we evaluate the heat storage terms of a subalpine meadow based on a ficld experiment conducted in the complex terrain of the eastern Qilian Mountains of Northwest China and their impact on the closure of the surface energy balance under such non-ideal conditions.During the night, the average sum of the storage terms was -5.5 W m~(-2),which corresponded to 10.4%of net radiation.The sum of the terms became positive at 0730 LST and negative again at about 1500 LST,with a maximum value of 19 W m~(-2) observed at approximately 0830 LST.During the day,the average of the sum of the storage terms was 6.5 W m~(-2),which corresponded to 4.0%of net radiation.According to the slopes obtained when linear regression of the net radiation and partitioned fluxes was forced through the origin,there is an imbalance of 14.0%in the subalpine meadow when the storage terms are not considered in the surface energy balance.This imbalance was improved by 3.4%by calculating the sum of the storage terms.The soil heat storage flux gave the highest contribution(1.59%),while the vegetation enthalpy change and the rest of the storage terms were responsible for improvements of 1.04%and 0.77%,respectively.

  12. An Assessment of Storage Terms in the Surface Energy Balance of a Subalpine Meadow in Northwest China

    Institute of Scientific and Technical Information of China (English)

    WANG Runyuan; ZHANG Qiang

    2011-01-01

    The heat storage terms in the soil-vegetation-atmosphere system may play an important role in the surface energy budget. In this paper, we evaluate the heat storage terms of a subaipine meadow based on a field experiment conducted in the complex terrain of the eastern Qilian Mountains of Northwest China and their impact on the closure of the surface energy balance under such non-ideal conditions. During the night,the average sum of the storage terms was -5.5 W m-2, which corresponded to 10.4% of net radiation. The sum of the terms became positive at 0730 LST and negative again at about 1500 LST, with a maximum value of 19 W m-2 observed at approximately 0830 LST. During the day, the average of the sum of the storage terms was 6.5 W m-2, which corresponded to 4.0% of net radiation. According to the slopes obtained when linear regression of the net radiation and partitioned fluxes was forced through the origin, there is an imbalance of 14.0% in the subalpine meadow when the storage terms are not considered in the surface energy balance. This imbalance was improved by 3.4% by calculating the sum of the storage terms. The soil heat storage flux gave the highest contribution (1.59%), while the vegetation enthalpy change and the rest of the storage terms were responsible for improvements of 1.04% and 0.77%, respectively.

  13. Discrete wavelet transform-based investigation into the variability of standardized precipitation index in Northwest China during 1960-2014

    Science.gov (United States)

    Yang, Peng; Xia, Jun; Zhan, Chesheng; Zhang, Yongyong; Hu, Sheng

    2017-02-01

    In this study, the temporal variations of the standard precipitation index (SPI) were analyzed at different scales in Northwest China (NWC). Discrete wavelet transform (DWT) was used in conjunction with the Mann-Kendall (MK) test in this study. This study also investigated the relationships between original precipitation and different periodic components of SPI series with datasets spanning 55 years (1960-2014). The results showed that with the exception of the annual and summer SPI in the Inner Mongolia Inland Rivers Basin (IMIRB), spring SPI in the Qinghai Lake Rivers Basin (QLRB), and spring SPI in the Central Asia Rivers Basin (CARB), it had an increasing trend in other regions for other time series. In the spring, summer, and autumn series, though the MK trends test in most areas was at the insignificant level, they showed an increasing trend in precipitation. Meanwhile, the SPI series in most subbasins of NWC displayed a turning point in 1980-1990, with the significant increasing levels after 2000. Additionally, there was a significant difference between the trend of the original SPI series and the largest approximations. The annual and seasonal SPI series were composed of the short periodicities, which were less than a decade. The MK value would increase by adding the multiple D components (and approximations), and the MK value of the combined series was in harmony with that of the original series. Additionally, the major trend of the annual SPI in NWC was based on the four kinds of climate indices (e.g., Atlantic Oscillation [AO], North Atlantic Oscillation [NAO], Pacific Decadal Oscillation [PDO], and El Nino-Southern Oscillation index [ENSO/NINO]), especially the ENSO.

  14. Spatiotemporal Variation of Karst Ecosystem Service Values and Its Correlation with Environmental Factors in Northwest Guangxi, China

    Science.gov (United States)

    Zhang, Mingyang; Zhang, Chunhua; Wang, Kelin; Yue, Yuemin; Qi, Xiangkun; Fan, Feide

    2011-11-01

    In this investigation we analyzed the spatiotemporal variation of ecosystem service values (ESVs) and its correlation with numerous environmental factors (EFs) for the karst region of Northwest Guangxi, China, from 1985 to 2005 using remote sensing, geographic information systems (GIS) and statistical techniques. The results indicate that historically ESVs for this karst region decreased from 1985 (109.652 billion Yuan) to 1990 (88.789 billion Yuan) and then increased at the turn of the twenty-first century. However, the ESVs in both 2000 (103.384 billion Yuan) and 2005 (106.257 billion Yuan) never achieved the level recorded in 1985. The total of nutrient cycling, organic production and gas regulation combined were 72.69, 64.57, 70.18 and 72.10% of ESVs in 1985, 1990, 2000 and 2005, respectively. In contrast, the ESVs of water conservation, soil reservation, recreation and culture were determined to be relatively low contributing only 17.44, 23.82, 19.26 and 24.76% of total ESVs, respectively, during these four years. With regards to the spatial distribution of ESVs, larger values were recorded in the west and smaller ones recorded in the east. The most significant factors that were deemed to influence ESVs are annual rainfall, per capita cropland, slope and vegetation coverage. Annual rainfall and slope exert a negative force, whereas per capita cropland and vegetation coverage exert a positive force on ESVs. The results of the study would suggest that ecosystem conditions of this important karst region have been improved as the result of the implementation of rocky desertification control policies.

  15. A Comparison of the Physical and Optical Properties of Anthropogenic Air Pollutants and Mineral Dust over Northwest China

    Institute of Scientific and Technical Information of China (English)

    王鑫; 浦伟; 史晋森; 闭建荣; 周天; 张雪荣; 任勇

    2015-01-01

    Emissions of mineral dust and its mixing with anthropogenic air pollutants aff ect both regional and global climates. Our fi eldwork in late spring 2007 (April 25–June 15) measured the physical and optical properties of dust storms mixed with local air pollutants at a rural site about 48 km southeast of central Lanzhou. Levels of air pollutants and aerosol optical properties were observed during the experiment, with concentrations of NOx (6.8 ± 3.3 ppb, average ± standard deviation), CO (694 ± 486 ppb), SO2 (6.2 ± 10 ppb), O3 (50.7 ± 13.1 ppb), and PM10 (172 ± 180 µg m−3), and aerosol scattering coeffi cient (164 ± 89 Mm−1; 1 Mm = 106 m) and absorption coeffi cient (11.7 ± 6.6 Mm−1), all much lower than the values observed during air pollution episodes in urban areas. During a major dust storm, the mass concentration of PM10 reached 4072 µg m−3, approximately 21-fold higher than in non-dust storm periods. The mixing ratios of trace gases declined noticeably after a cold front passed through. The observed CO/SO2 and CO/NOx ratios during air pollution episodes were 4.2–18.3 and 13.7–80.5, respectively, compared with the corresponding ratios of 38.1–255.7 and 18.0–245.9 during non-pollution periods. Our investigations suggest that dust storms have a signifi cant infl uence on air quality in areas far from their source, and this large-scale transport of dust and air pollutants produces major uncertainties in the quantifi cation of the global eff ects of emissions over Northwest China.

  16. Evaluation of Penman-Monteith model applied to a maize field in the arid area of Northwest China

    Directory of Open Access Journals (Sweden)

    W.-Z. Zhao

    2010-01-01

    Full Text Available The Penman-Monteith (P-M model has been applied to estimate evapotranspiration in terrestrial ecosystem widely in the world. As shown in many studies, bulk canopy resistance is an especially important factor in the application of P-M model. In this study, the authors used the Noilhan and Planton (N-P approach and Jacobs and De Bruin (J-D approach to express the bulk canopy resistance. The application of P-M mode to a maize field with two approaches in the arid area of Northwest China was evaluated by the measured half-hourly values from the eddy covariance system. The results indicate that the N-P approach underestimates slightly the bulk canopy resistance, while the J-D approach overestimates that. The estimation of bulk canopy resistance with N-P approach was then better and more consistent than that with J-D approach during the entire maize growing season. Correspondingly, the P-M model with J-D bulk canopy resistance slightly underestimated the latent heat flux throughout the maize growing season, but overestimated the latent heat flux during the dry period of the soil as compared to that with N-P approach. The good fitness of the simulated latent heat flux by the P-M model with N-P bulk canopy resistance approach to the measured one at a half-hour time step demonstrates the application of the approach is reasonable in the relative homogenous and not drought-stressed maize fields of the arid areas during the entire growing season. Further researches are discussed on enhancing the field observation, taking the correction for atmospheric stability into estimating aerodynamic resistance, to improve the performance of P-M model to simulate evapotranspiration in the cropped fields.

  17. Linear and nonlinear characteristics of the runoff response to regional climate factors in the Qira River basin, Xinjiang, Northwest China.

    Science.gov (United States)

    Xue, Jie; Gui, Dongwei

    2015-01-01

    The inland river watersheds of arid Northwest China represent an example of how, in recent times, climatic warming has increased the complexity of Earth's hydrological processes. In the present study, the linear and nonlinear characteristics of the runoff response to temperature and precipitation were investigated in the Qira River basin, located on the northern slope of the Kunlun Mountains. The results showed that average temperature on annual and seasonal scales has displayed a significantly increasing trend, but this has not been reflected in accumulated precipitation and runoff. Using path analysis, a positive link between precipitation and runoff was found both annually and in the summer season. Conversely, it was found that the impact of temperature on runoff has been negative since the 1960s, attributable to higher evaporation and infiltration in the Qira River basin. Over the past 50 years, abrupt changes in annual temperature, precipitation and runoff occurred in 1997, 1987 and 1995, respectively. Combined with analysis using the correlation dimension method, it was found that the temperature, precipitation and runoff, both annually and seasonally, possessed chaotic dynamic characteristics, implying that complex hydro-climatic processes must be introduced into other variables within models to describe the dynamics. In addition, as determined via rescaled range analysis, a consistent annual and seasonal decreasing trend in runoff under increasing temperature and precipitation conditions in the future should be taken into account. This work may provide a theoretical perspective that can be applied to the proper use and management of oasis water resources in the lower reaches of river basins like that of the Qira River.

  18. Middle Permian Seamount from Xiahe Area, Gansu Province, Northwest China: Zircon U-Pb Age, Biostratigraphy and Tectonic Implications

    Institute of Scientific and Technical Information of China (English)

    Kou Xiaohu; Zhang Kexin; Zhu Yunhai; Chen Zhongqiang; Lin Qixiang; Chen Fenning; Huang Jinyuan

    2009-01-01

    The well-preserved seamount buildups are documented from the northwestern Qinling (秦岭) orogenic belts, Northwest China. The study sections are located in the Ganjia (甘加) area of the Xiahe (夏河) County, Gansu (甘肃) Province. The dark basalt and overlying massive reef carbonate characterize the Xiahe seamount buildup. Basalts are dominated by the olivine type of rocks and bear distinct porphyritic textures, and fumarole and amygdaloidal structures. The basaits are dominated by SiO2(up to 48.49 wt.%-52.29 wt.%) followed by (Na2O+ K2O) (3.80 wt.%-4.96 wt.%) and TiO2 (2.04 wt.%-2.52 wt.%). They are featured by considerably high content of Ti. The tholeilteseries rocks dominate the basalts, while calc-alkali-series rocks are also present. The REE of the basalts shows the LREE-enrichment type with distinct positive Eu abnormal. The trace elements of the basalts are characterized by the lack of P and high content of Ti. These geochemical signals suggest that the Xiahe basalts were formed in an ocean-island setting. The LA ICP-MS zircon U-Pb age of the basalts is 267.6±5 Ma, which is reinforced by the presnce of the fusuHnid Neoschwagerina Zone of the Wordian (Middle Permian) in the limestone interbeds of the basalts. Integration of petrological and geochemical studies of seamount basaits and lateral correlation of seamount buildups reveals that the Qinling-qilian-Kunlun orogenic belts were probably the archipelagtc oceans during the Permian.

  19. Quantitative analysis of burden of infectious diarrhea associated with floods in northwest of anhui province, china: a mixed method evaluation.

    Science.gov (United States)

    Ding, Guoyong; Zhang, Ying; Gao, Lu; Ma, Wei; Li, Xiujun; Liu, Jing; Liu, Qiyong; Jiang, Baofa

    2013-01-01

    Persistent and heavy rainfall in the upper and middle Huaihe River of China brought about severe floods during the end of June and July 2007. However, there has been no assessment on the association between the floods and infectious diarrhea. This study aimed to quantify the impact of the floods in 2007 on the burden of disease due to infectious diarrhea in northwest of Anhui Province. A time-stratified case-crossover analysis was firstly conducted to examine the relationship between daily cases of infectious diarrhea and the 2007 floods in Fuyang and Bozhou of Anhui Province. Odds ratios (ORs) of the flood risk were quantified by conditional logistic regression. The years lived with disability (YLDs) of infectious diarrhea attributable to floods were then estimated based on the WHO framework of the calculating potential impact fraction in the Burden of Disease study. A total of 197 infectious diarrheas were notified during the exposure and control periods in the two study areas. The strongest effect was shown with a 2-day lag in Fuyang and a 5-day lag in Bozhou. Multivariable analysis showed that floods were significantly associated with an increased risk of the number cases of infectious diarrhea (OR = 3.175, 95%CI: 1.126-8.954 in Fuyang; OR = 6.754, 95%CI: 1.954-23.344 in Bozhou). Attributable YLD per 1000 of infectious diarrhea resulting from the floods was 0.0081 in Fuyang and 0.0209 in Bozhou. Our findings confirm that floods have significantly increased the risks of infectious diarrhea in the study areas. In addition, prolonged moderate flood may cause more burdens of infectious diarrheas than severe flood with a shorter duration. More attention should be paid to particular vulnerable groups, including younger children and elderly, in developing public health preparation and intervention programs. Findings have significant implications for developing strategies to prevent and reduce health impact of floods.

  20. [Microbial community and its activities in canopy- and understory humus of two montane forest types in Ailao Mountains, Northwest China].

    Science.gov (United States)

    Liu, Yong-jie; Liu, Wen-yao; Chen, Lin; Zhang, Han-bo; Wang, Gao-sheng

    2010-09-01

    Mid-montane moist evergreen broadleaved forest (MMF) and top-montane dwarf mossy forest (DMF) are the two major natural forest types in subtropical mountainous area of Ailao Mountains, Northwest China. In this paper, a comparative study was made on the microbial composition, quantity, biochemical activity, metabolic activity, and their seasonal dynamics in the canopy- and understory humus of the two forest types. The composition, quantity, and metabolic activity of the microbes in the canopy humus of dominant tree species in MMF and DMF were also analyzed. In the canopy humus of the two forest types, the amounts of fungi and actinomycetes, microbial biomass C and N, and intensities of nitrogen fixation and cellulose decomposition were significantly higher than those in understory humus. Meanwhile, the amount of cellulose-decomposing microbes (ACDM), cellulose decomposition intensity, microbial biomass C and N, and metabolic activity in the canopy humus of MMF were significantly higher than those of DMF. The amounts of bacteria, fungi, and aerobic nitrogen-fixing bacteria (ANFB) and the metabolic activity in the canopy humus of MMF and DMF were significantly higher in wet season than in dry season, while a contradictory trend was observed on the amount of actinomycetes. No significant difference was observed on the amount of ACDM between wet season and dry season. For the two forest types, the amounts of microbes and their biochemical activities in canopy humus had a larger seasonal variation range than those in understory humus. There was a significant difference in the amounts of the microbes in canopy humus among the dominant tree species in MMF and DMF, especially in wet season. The microbes in canopy humus played important roles in maintaining the biodiversity of epiphytes in the canopy, and in supplying the needed nutrients for the vigorous growth of the epiphytes.

  1. Long-term effect of manure and fertilizer on soil organic carbon pools in dryland farming in northwest China.

    Science.gov (United States)

    Liu, Enke; Yan, Changrong; Mei, Xurong; Zhang, Yanqing; Fan, Tinglu

    2013-01-01

    An understanding of the dynamics of soil organic carbon (SOC) as affected by farming practices is imperative for maintaining soil productivity and mitigating global warming. The objectives of this study were to investigate the effects of long-term fertilization on SOC and SOC fractions for the whole soil profile (0-100 cm) in northwest China. The study was initiated in 1979 in Gansu, China and included six treatments: unfertilized control (CK), nitrogen fertilizer (N), nitrogen and phosphorus (P) fertilizers (NP), straw plus N and P fertilizers (NP+S), farmyard manure (FYM), and farmyard manure plus N and P fertilizers (NP+FYM). Results showed that SOC concentration in the 0-20 cm soil layer increased with time except in the CK and N treatments. Long-term fertilization significantly influenced SOC concentrations and storage to 60 cm depth. Below 60 cm, SOC concentrations and storages were statistically not significant between all treatments. The concentration of SOC at different depths in 0-60 cm soil profile was higher under NP+FYM follow by under NP+S, compared to under CK. The SOC storage in 0-60 cm in NP+FYM, NP+S, FYM and NP treatments were increased by 41.3%, 32.9%, 28.1% and 17.9%, respectively, as compared to the CK treatment. Organic manure plus inorganic fertilizer application also increased labile soil organic carbon pools in 0-60 cm depth. The average concentration of particulate organic carbon (POC), dissolved organic carbon (DOC) and microbial biomass carbon (MBC) in organic manure plus inorganic fertilizer treatments (NP+S and NP+FYM) in 0-60 cm depth were increased by 64.9-91.9%, 42.5-56.9%, and 74.7-99.4%, respectively, over the CK treatment. The POC, MBC and DOC concentrations increased linearly with increasing SOC content. These results indicate that long-term additions of organic manure have the most beneficial effects in building carbon pools among the investigated types of fertilization.

  2. Long-term effect of manure and fertilizer on soil organic carbon pools in dryland farming in northwest China.

    Directory of Open Access Journals (Sweden)

    Enke Liu

    Full Text Available An understanding of the dynamics of soil organic carbon (SOC as affected by farming practices is imperative for maintaining soil productivity and mitigating global warming. The objectives of this study were to investigate the effects of long-term fertilization on SOC and SOC fractions for the whole soil profile (0-100 cm in northwest China. The study was initiated in 1979 in Gansu, China and included six treatments: unfertilized control (CK, nitrogen fertilizer (N, nitrogen and phosphorus (P fertilizers (NP, straw plus N and P fertilizers (NP+S, farmyard manure (FYM, and farmyard manure plus N and P fertilizers (NP+FYM. Results showed that SOC concentration in the 0-20 cm soil layer increased with time except in the CK and N treatments. Long-term fertilization significantly influenced SOC concentrations and storage to 60 cm depth. Below 60 cm, SOC concentrations and storages were statistically not significant between all treatments. The concentration of SOC at different depths in 0-60 cm soil profile was higher under NP+FYM follow by under NP+S, compared to under CK. The SOC storage in 0-60 cm in NP+FYM, NP+S, FYM and NP treatments were increased by 41.3%, 32.9%, 28.1% and 17.9%, respectively, as compared to the CK treatment. Organic manure plus inorganic fertilizer application also increased labile soil organic carbon pools in 0-60 cm depth. The average concentration of particulate organic carbon (POC, dissolved organic carbon (DOC and microbial biomass carbon (MBC in organic manure plus inorganic fertilizer treatments (NP+S and NP+FYM in 0-60 cm depth were increased by 64.9-91.9%, 42.5-56.9%, and 74.7-99.4%, respectively, over the CK treatment. The POC, MBC and DOC concentrations increased linearly with increasing SOC content. These results indicate that long-term additions of organic manure have the most beneficial effects in building carbon pools among the investigated types of fertilization.

  3. Composition, origin and weathering process of surface sediment in Kumtagh Desert, Northwest China

    Institute of Scientific and Technical Information of China (English)

    XU Zhiwei; LU Huayu; ZHAO Cunfa; WANG Xianyan; SU Zhizhua; WANG Zhenting; LIU Hongyi; WANG Lixin; LU Qi

    2011-01-01

    Kumtagh Desert is one of the eight biggest deserts in China,but poorly investigated before our interdisciplinary study because of the difficulty of access.In this paper,33 representative surface sediment samples were collected from the Kumtagh Desert and analyzed in the laboratory to obtain heavy mineral components and geochemical element contents.Results show that various kinds of heavy minerals are present in these samples,with high levels of epidote and hornblende.Si and AI take up a large part of chemical composition.Compared with the average composition of geochemical elements of the upper continental crust (UCC),except Si and Ca,all elements are depleted to a certain degree; Fe,Mg,Ca,P,Ti and Mn have high correlation coefficients in their contents.The mineral and geochemical composition of the Kumtagh Desert sediments have a similarity with that of rocks of Altyn Tagh Mountains,and the surface sediments of the alluvial/diluvial fans around the Altyn Tagh Mountains and that of the Taklamakan Desert,indicating that one major source of the Kumtagh Desert sediments is located in the Altyn Tagh Mountains.Alluvial deposits and lake sediments in Aqik valley and lower reaches of Shule River are prone to be eroded and transported by the strong northeasterly wind into the Kumtagh Desert,forming another source of the desert deposits.An A-CN-K ternary diagram shows that a weak degree chemical weathering by the loss of Na and K occurred in these sediments,whereas A-CNK-FM temary diagram suggests that Fe and Mg have undergone a significant chemical differentiation.Physical weathering processes cause easy erosion and enrichment in fine particles for mafic minerals,thus coarse desert sand particles can be relatively depleted in Fe and Mg.The mineral and geochemical composition of sediments in arid regions experiencing less chemical weathering are mostly affected by physical weathering.

  4. Multi-Temporal Remotely Sensed Data for Degradation Dynamics in Linxia Rangeland, Northwest China

    Directory of Open Access Journals (Sweden)

    Xinyang Yu

    2017-03-01

    Full Text Available The importance of accurately monitoring rangeland degradation dynamics over decades is increasing in Linxia rangeland, the birthplace of the Yellow River in China. Since 2000, the Chinese government has implemented the “Grain for Green” program and enforced a grazing ban in Gansu province, one of the most degraded provinces, to mitigate the problem of rangeland degradation. The effects of these policies are controversial and have become a topic of public concern. In this study, a grading system was established for the estimation of Linxia rangeland degradation. Degrees of rangeland degradation were interpreted and the spatio-temporal dynamics of the degraded rangeland through several study periods were mapped and monitored using the Linear Spectral Mixture Analysis method on Landsat Thematic Mapper (TM/ETM+ (Enhanced Thematic Mapper Plus images for the years of 1996, 2001, 2006, and 2011. The results demonstrated that the time around the year 2001 appeared to be a turning point of the rangeland degradation reversion course, as the rangeland degradation reversed significantly since 2001. From 1996 to 2001, the total degraded area in Linxia rangeland increased from 2922.01 km2 to 3048.48 km2 (+4.33%, and decreased by 4.54% to 2909.97 km2 in 2011; the non-degraded rangeland gradually increased from 602.74 km2 to 710.01 km2, an increase of 17.80%. Degraded rangeland vegetation was restored significantly during 2001–2011: the area of slightly degraded rangeland increased by 3.71% and 3.83% annually during 2001–2006 and 2006–2011 intervals, respectively, and the area of moderately and severely degraded rangeland decreased annually by 4.77% and 2.41% from 2001 to 2006, and 4.58% and 0.81% during 2006–2011, respectively. These results indicated that the “Grain for Green” program and grazing ban policy, together with other ecological impacting factors, helped reverse the rangeland degradation and promote the rehabilitation of rangeland

  5. Factors Affecting Migration Intentions in Ecological Restoration Areas and Their Implications for the Sustainability of Ecological Migration Policy in Arid Northwest China

    Directory of Open Access Journals (Sweden)

    Yongjin Li

    2014-11-01

    Full Text Available Ecological migration policy has been proposed and implemented as a means for depopulating ecological restoration areas in the arid Northwest China. Migration intention is critical to the effectiveness of ecological migration policy. However, studies on migration intention in relation to ecological migration policy in China remain scant. Thus this paper aims to investigate the rural residents’ migration intentions and their affecting factors under ecological migration policy in Minqin County, an ecological restoration area, located at the lower terminus of Shiyang River Basin in arid Northwest China. The data for this study come from a randomly sampled household questionnaire survey. Results from logistic regression modelling indicate that most residents do not intend to migrate, despite rigid eco-environmental conditions and governance polices threatening livelihood sustainability. In addition to demographic and socio-economic factors, the eco-environmental factors are also significantly correlated with the possibility of a resident intending to migrate. The implications of the significant independent variables for the sustainability of ecological migration policy are discussed. The paper concludes that ecological migration policies may ultimately be more sustainable when taking into account household interests within complex migration intention contexts, such as household livelihoods dynamics and environmental change.

  6. Characterization of groundwater in the Ejina Basin,northwest China:hydrochemical and environmental isotopes approaches

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    To characterize the groundwater in the Ejina Basin,surface and groundwater samples were collected in May and October of 2002.On-site analyses included temperature,electrical conductance(EC),total alkalinity(as HCO 3) by titration,and pH.Chemical analyses were undertaken at the Geochemistry Laboratory of the Cold and Arid Region Environmental and Engineering Institute,Chinese Academy of Sciences,Lanzhou,China.The pH of the groundwater ranged from 7.18 to 8.90 with an average value of 7.72,indicating an alkaline nature.The total dissolved solids(TDS) of the groundwater ranged from 567.5 to 5,954.4 mg/L with an average of 1,543.1 mg/L and a standard deviation of 1,471.8 mg/L.According to the groundwater salinity classification of Robinove et al.(1958),47.4 percent of the samples were brackish and the remainder were fresh water.The ion concentration of the groundwater along the riverbed and near the southern margin of the basin were lower than those farther away from the riverbed.The groundwater in the study area was of Na +-HCO 3 type near the bank of the Heihe River and in the southern margin of the basin,while Na +-SO 4 2-Cl type samples were observed in the terminal lake region.In the desert area the groundwater reached a TDS of 3,000-6,000 mg/L and was predominantly by a Na +-Cl chemistry.Br/Cl for the water of Ejina Basin indicates an evaporite origin for the groundwater with a strongly depleted Br/Cl ratio(average 0.000484).The surface water was slightly enriched in Br/Cl(average 0.000711) compared with groundwater.The calculated saturation index(SI) for calcite and dolomite of the groundwater samples range from 0.89 to 1.31 and 1.67 to 2.67 with averaged 0.24 and 0.61,respectively.About 97 percent of the groundwater samples were kinetically oversaturated with respect to calcite and dolomite,and all the samples were below the equilibrium state with gypsum.Using isotope and hydrochemical analyses,this study investigated the groundwater evolution and its residence

  7. Structural Variation of an Atmospheric Heat Source over the Qinghai-Xizang Plateau and Its Influence on Precipitation in Northwest China

    Institute of Scientific and Technical Information of China (English)

    WEI Na; GONG Yuanfa; HE Jinhai

    2009-01-01

    NCEP/NCAR reanalysis data and a 47-year precipitation dataset are utilized to analyze the relationship between an atmospheric heat source (hereafter called ) over the Qinghai-Xizang Plateau (QXP) and its surrounding area and precipitation in northwest China.Our main conclusions are as follows:(1) The horizontal distribution of and its changing trend are dramatic over QXP in the summer.There are three strong centers of over the south side of QXP with obvious differences in the amount of yearly precipitation and the number of heat sinks predominate in the arid and semi-arid regions of northwest China (NWC),beside the northern QXP with an obvious higher intensity in years with less precipitation.(2) In the summer,the variation of the heat source's vertical structure is obviously different between greater and lesser precipitation years in eastern northwest China (ENWC).The narrow heat sink belt forms between the northeast QXP and the southwestern part of Lake Baikal.In July and August of greater precipitation years,the heating center of the eastern QXP stays nearly over 35°N,and at 400 hPa of the eastern QXP,the strong upward motion of the heating center constructs a closed secondary vertical circulation cell over the northeast QXP (40°-46°N),which is propitious to add precipitation over the ENWC.Otherwise,the heating center shifts to the south of 30°N and disappears in July and August of lesser precipitation years,an opposite secondary circulation cell forms over the northeast QXP,which is a disadvantage for precipitation.Meanwhile,the secondary circulation cell in years with more or less precipitation over the ENWC is also related to the heat source over the Lake Baikal. (3) The vertical structure of the heat source over the western QXP has obvious differences between greater and lesser precipitation years in western northwest China in June and July.The strong/weak heat source over the western QXP produces relatively strong/weak ascending motion and

  8. Investigating the Impact of Shading Effect on the Characteristics of a Large-Scale Grid-Connected PV Power Plant in Northwest China

    OpenAIRE

    2014-01-01

    Northwest China is an ideal region for large-scale grid-connected PV system installation due to its abundant solar radiation and vast areas. For grid-connected PV systems in this region, one of the key issues is how to reduce the shading effect as much as possible to maximize their power generation. In this paper, a shading simulation model for PV modules is established and its reliability is verified under the standard testing condition (STC) in laboratory. Based on the investigation result ...

  9. The status of vitamin B12 and folate among Chinese women: a population-based cross-sectional study in northwest China.

    Science.gov (United States)

    Dang, Shaonong; Yan, Hong; Zeng, Lingxia; Wang, Quanli; Li, Qiang; Xiao, Shengbin; Fan, Xiaojing

    2014-01-01

    To assess the status of the vitamin B12 and folate of Chinese women living in northwest China. A population-based cross-sectional study was conducted in 2008 among Chinese women aged 10-49 years living in Shaanxi province of northwest China. A stratified multistage random sampling method was adopted to obtain a sample of 1170 women. The women were interviewed for collection of their background information and their plasma vitamin B12 and folate were measured with the immunoassay method. The status of both vitamins was evaluated and the prevalence of deficiency was estimated. The median value of the women was 214.5 pg/mL for vitamin B12 and 4.6 ng/mL for folate. The urban women had a significantly higher vitamin B12 (254.1 vs. 195.9 pg/mL) but lower folate (4.4 vs. 4.7 ng/mL) than rural women. Total prevalence of deficiency was 45.5% (95% CI: 42.6% ∼ 48.4%) for vitamin B12 and 14.7% (95% CI: 12.6% ∼ 16.8%) for folate. About 36% of women presented vitamin B12 deficiency alone, 5.2% belonged to folate deficiency alone and 9.5% was combined deficiency in both vitamins. More than 25% of the women were in marginal vitamin B12 status (200-299 pg/mL) and 60% in marginal status of folate (3-6 ng/mL). About 75.2% of rural women with folate deficiency were deficient in vitamin B12 and 46% for urban women. Quantile regression model found decreasing coefficient of folate status across 73 different quantiles of vitamin B12, which indicated that the women with folate deficiency had lower vitamin B12 significantly compared with those with no deficiency. The deficiency of vitamin B12 and folate is still prevalent among the Chinese women in northwest China. Vitamin B12 deficiency could be more serious and the improvement of poor vitamin B12 status should be invoked when practicing the supplementation of folate against the neural tube defects in northwest China.

  10. Effects of Ultra-drying on Viability and Physiological Characteristics of Platycladus orientalis Seed from Arid and Semiarid Areas of Northwest China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In order to supply quality seed for vegetation restoration in arid and semiarid areas of Northwest China, the effects of Platycladus orientalis seed storage under ultra-drying and accelerated aging were studied. The seeds were dried from 6.8% to 5.1%, 4.4%, 3.7% and 2.2% MC, respectively, in a desiccator with the silica gel. The germination energy, germination percentage, germination index and vigor index of the seed were investigated. After ultra-drying, groups of seeds were carried on the accelerated agin...

  11. Diurnal and seasonal variations in carbon dioxide exchange in ecosystems in the Zhangye oasis area, Northwest China.

    Directory of Open Access Journals (Sweden)

    Lei Zhang

    Full Text Available Quantifying carbon dioxide exchange and understanding the response of key environmental factors in various ecosystems are critical to understanding regional carbon budgets and ecosystem behaviors. For this study, CO2 fluxes were measured in a variety of ecosystems with an eddy covariance observation matrix between June 2012 and September 2012 in the Zhangye oasis area of Northwest China. The results show distinct diurnal variations in the CO2 fluxes in vegetable field, orchard, wetland, and maize cropland. Diurnal variations of CO2 fluxes were not obvious, and their values approached zero in the sandy desert, desert steppe, and Gobi ecosystems. Additionally, daily variations in the Gross Primary Production (GPP, Ecosystem Respiration (Reco and Net Ecosystem Exchange (NEE were not obvious in the sandy desert, desert steppe, and Gobi ecosystems. In contrast, the distributions of the GPP, Reco, and NEE show significant daily variations, that are closely related to the development of vegetation in the maize, wetland, orchard, and vegetable field ecosystems. All of the ecosystems are characterized by their carbon absorption during the observation period. The ability to absorb CO2 differed significantly among the tested ecosystems. We also used the Michaelis-Menten equation and exponential curve fitting methods to analyze the impact of Photosynthetically Active Radiation (PAR on the daytime CO2 flux and impact of air temperature on Reco at night. The results show that PAR is the dominant factor in controlling photosynthesis with limited solar radiation, and daytime CO2 assimilation increases rapidly with PAR. Additionally, the carbon assimilation rate was found to increase slowly with high solar radiation. The light response parameters changed with each growth stage for all of the vegetation types, and higher light response values were observed during months or stages when the plants grew quickly. Light saturation points are different for different

  12. Estimation of subsurface formation temperature in the Tarim Basin, northwest China: implications for hydrocarbon generation and preservation

    Science.gov (United States)

    Liu, Shaowen; Lei, Xiao; Feng, Changge; Hao, Chunyan

    2016-07-01

    Subsurface formation temperature in the Tarim Basin, northwest China, is vital for assessment of hydrocarbon generation and preservation, and of geothermal energy potential. However, it has not previously been well understood, due to poor data coverage and a lack of highly accurate temperature data. Here, we combined recently acquired steady-state temperature logging data with drill stem test temperature data and measured rock thermal properties, to investigate the geothermal regime and estimate the subsurface formation temperature at depth in the range of 1000-5000 m, together with temperatures at the lower boundary of each of four major Lower Paleozoic marine source rocks buried in this basin. Results show that heat flow of the Tarim Basin ranges between 26.2 and 66.1 mW/m2, with a mean of 42.5 ± 7.6 mW/m2; the geothermal gradient at depth of 3000 m varies from 14.9 to 30.2 °C/km, with a mean of 20.7 ± 2.9 °C/km. Formation temperature estimated at the depth of 1000 m is between 29 and 41 °C, with a mean of 35 °C, while 63-100 °C is for the temperature at the depth of 3000 m with a mean of 82 °C. Temperature at 5000 m ranges from 97 to 160 °C, with a mean of 129 °C. Generally spatial patterns of the subsurface formation temperature at depth are basically similar, characterized by higher temperatures in the uplift areas and lower temperatures in the sags, which indicates the influence of basement structure and lateral variations in thermal properties on the geotemperature field. Using temperature to identify the oil window in the source rocks, most of the uplifted areas in the basin are under favorable condition for oil generation and/or preservation, whereas the sags with thick sediments are favorable for gas generation and/or preservation. We conclude that relatively low present-day geothermal regime and large burial depth of the source rocks in the Tarim Basin are favorable for hydrocarbon generation and preservation. In addition, it is found that the

  13. Origin of high Sr/Y-type granitic magmatism in the southwestern of the Alxa Block, Northwest China

    Science.gov (United States)

    Zhou, Xiao-Chun; Zhang, Hong-Fei; Luo, Bi-Ji; Pan, Fa-Bin; Zhang, Sha-Sha; Guo, Liang

    2016-07-01

    The petrogenesis of high Sr/Y-type magmas is still open to debate. Usually, such magmas could result from melting under high-pressure settings (> 12 kbar). In this paper, we gave an example that some high Sr/Y-type magmas could originate from melting of crustal materials at pressure of 10-12 kbar. We carried out a study of petrogenesis for Devonian high Sr/Y granites from the Beidashan batholith (397-411 Ma), southwestern Alxa Block, Northwest China. The Beidashan granites have SiO2 (69.21-74.60 wt.%) and Al2O3 (14.01-16.20 wt.%) with A/CNK ratios of 0.99-1.08. According to their trace element compositions and whole-rock zirconium saturation temperatures (TZr), the Beidashan granites can be divided into two groups: Group I ((Dy/Yb)N = 1.2-3.0, Eu/Eu* = 0.77-1.3, TZr = 761-856 °C), resulted from fluid-absent partial melting of mafic to intermediate crustal materials leaving garnet residuum at pressure of ~ 12 kbar, and Group II ((Dy/Yb)N = 0.76-2.16, Eu/Eu* = 1.7-5.3, TZr = 651-785 °C), formed by fluid-present melting of mafic to intermediate crustal materials with residual amphibole in the source at pressure of ~ 10 kbar. Both Group I and Group II show high Sr/Y and (La/Yb)N features. They show ISr = 0.7134-0.7180, εNd(t) = - 6.61 to - 9.71, T2DM = 1.7-1.9 Ga; εHf(t) = - 5.6 to - 9.9 and TDMC = 1.7-2.0 Ga, indicating that the Beidashan high Sr/Y granites were derived from melting of crustal basement materials. Our results suggest that some high Sr/Y-type granites formed under relatively lower pressure conditions (~ 10-12 kbar), and they could not be an indicative of partial melting of thickened crust.

  14. Paleozoic adakitic rocks in the northern Altyn Tagh, northwest China: Evidence for progressive crustal thickening beneath the Dunhuang Block

    Science.gov (United States)

    Bao, Weihang; Long, Xiaoping; Yuan, Chao; Sun, Min; Zhao, Guochun; Wang, Yujing; Guan, Yili; Zhang, Yunying

    2017-02-01

    To constrain the Phanerozoic crustal evolution of the Dunhuang Block, new whole-rock geochemistry, zircon U-Pb ages and Hf isotopic data were determined for three Paleozoic granitic plutons in the northern Altyn Tagh, northwest China. Zircon U-Pb dating of these plutons, including gneissic granite, mylonitic granite and augen gneiss, yielded Middle Devonian to Early Carboniferous crystallization ages of 358 ± 4 Ma, 382 ± 4 Ma and 332 ± 2 Ma, respectively. The gneissic granites are characterized by a small SiO2 variation (69.11-70.33 wt.%) with moderate K2O (3.07-3.55 wt.%), Na2O (3.61-4.08 wt.%), low Fe2O3T (2.25-2.84 wt.%) and MgO (1.04-1.25 wt.%). The granites are weakly peraluminous with moderate aluminium saturation indexes (ASI = 1.02-1.08) and exhibit the geochemical features of high-K calc-alkaline igneous rocks. Although the major element contents of the mylonitic granites and the augen gneisses are different from those of the gneissic granites, all three plutons show similar REE patterns and trace element variations. Rocks from these plutons are all LREE-enriched and show relatively flat HREE patterns with pronounced depletions in Ba, Nb, Ta, Ti and negative Eu anomalies. Moreover, the rocks are characterized by high Sr (330.7-656 ppm), low Yb (0.513-1.521 ppm) and Y (5.199-13.73 ppm), and thus have high Sr/Y ratios (32-122), showing geochemical affinities of adakitic rocks. Their negative εHf(t) values, low MgO, Cr, Co and Ni contents indicate a continental crust origin without significant involvement of mantle-derived materials. The negative Eu anomalies, low Yb and Y contents of these granitic rocks reveal that plagioclase and garnet are major residue minerals in the magma source. All the geochemical characteristics demonstrate that these adakitic plutons were produced by partial melting of thickened lower crust at relatively shallow depths under high amphibolite or granulite facies and did not reach the eclogite facies. Combining this with the

  15. Changes in Socioeconomic Inequality of Low Birth Weight and Macrosomia in Shaanxi Province of Northwest China, 2010–2013

    Science.gov (United States)

    Pei, Leilei; Kang, Yijun; Zhao, Yaling; Cheng, Yue; Yan, Hong

    2016-01-01

    Abstract Socioeconomic disparities in birth weights (BWs) are associated with lifelong differences in health and productivity. Understanding socioeconomic disparities in BW is presently of concern to develop public health interventions that promote a good start in life in Northwest China. In the study, our objective is to investigate the socioeconomic disparities in low and high BW from 2010 to 2013 in this region. Those single live births were recruited using a stratified multistage sampling method in Shaanxi province from August to December 2013. Data were collected with a structured questionnaire and a review of birth certificates. Socioeconomic status (SES) was stratified based on the calculated household wealth index. Prevalence differences (PDs) and concentration indices (CIs) were used to depict the SES inequality of low BW (LBW) and macrosomia. Information for 28722 single live births born were obtained in Shaanxi province. From 2010 to 2013, the overall rates of LBW decreased, and the difference in LBW across differing SES groups decreased by 0.7% (boys, 0.4%; girls, 0.8%). From 2010 to 2013, the overall rates of macrosomia increased by 14.3% (boys, 17.5%; girls, 7.8%), whereas the PDs in macrosomia across various SES groups remained unchanged. From 2010 to 2013, concentration indices for SES inequalities in LBW and macrosomia confirmed the results shown by differences in prevalence. Compared with mothers of high SES, those in low SES group were significantly older, less educated, engaged in farming with less availabile healthcare, and engaged in unhealthy lifestyles (eg, exposure to secondhand smoke) during pregnancy, regardless of the baby's sex. From 2010 to 2013, in Shaanxi province, the negative association between socioeconomic status and LBW weakened. Rates of macrosomia were higher in those of high SES, but the SES disparities varied insignificantly over the same time. Our findings may provide valuable insights to direct healthcare policies for

  16. Water isotope variations in the snow pack and summer precipitation at July 1 Glacier, Qilian Mountains in northwest China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This paper presents the stable isotope data of the snow pack and summer precipitation collected at the July 1 Glacier, Qilian Mountains in northwest China and analyses their relationships with meteorological factors. On an event scale, there is no temperature effect on the δ18O values in the summer precipitation, whereas the amount effect is shown to be clear. By tracing the moisture transport history and comparing the precipitation with its isotopic composition, it is shown that this amount effect not only reflects the change in moisture trajectory, which is related to the monsoon activities, but is also associated with the cooling degree of vapor in the cloud, the evaporation of falling raindrops and the isotopic exchange between the falling drops and the atmospheric vapor. As very little precipitation occurs in winter, the snow pack profile mainly represents the precipitation in the other three seasons. There are low precipitation δ18O ratios in summer and high ratios in spring and autumn. The Meteoric Water Line (MLW) for the summer precipitation is δD = 7.6 δ18O + 13.3, which is similar to that at Delingha, located in the south rim of the Qilian Mountains. The MWL for the snow pack is δD = 10.4 δ18O + 41.4, showing a large slope and intercept. The deuterium excess (d) of the snow pack is positively correlated with δ18O, indicating that both d and δ18O decrease from spring to summer and increase from early autumn to early spring. This then results in the high slope and intercept of the MWL. Seasonal fluctuations of d in the snow pack indicate the change of moisture source and trajectory. During spring and autumn, the moisture originates from continental recycling or rapid evaporation over relatively warm water bodies like Black, Caspian and Aral Seas when the dry westerly air masses pass over them, hence very high d values in precipitation are formed. During summer, the monsoon is responsible for the low d values. This indicates that the monsoon can

  17. [Moisture and nutrient characteristics of deep layer soil in apple orchards on the Luochuan highland of Shaanxi, Northwest China].

    Science.gov (United States)

    Cao, Yu; Jumahan, Kasimu; Fan, Peng; Zhang, Li-Na; Li, Jun

    2013-02-01

    Taking the 11-, 15-, 20-, and 43 years old apple orchards on the Luochuan highland of Shaanxi, Northwest China as test objects, this paper measured the moisture content in 0-1500 cm soil layer and the organic matter and total and available nitrogen, phosphorous, and potassium contents in 0-300 cm soil layer, with the soil moisture and nutrient regimes as well as their variation characteristics with apple tree age and soil depth analyzed. The moisture content in 0-1500 cm soil layer in 11-, 15-, 20-, and 43 years old apple orchards was averagely 18.6%, 13.7%, 17.0%, 11.5%, and 13.1%, respectively, and decreased with apple tree age. Soil desiccation did not occurr in the orchards with supplementary irrigation, but a slight or medium soil desiccation occurred in the rainfed orchards. Nevertheless, the moisture content in 0-300 cm soil layer in the rainfed orchards was still higher than that in wheat field. The contents of organic matter and total and available nitrogen in 0-300 cm soil layer in the five apple orchards were less than 10 g.kg-1, 0.75 g. kg-1, and 50 mg.kg-1, respectively, all at shortage level, whilst the content of available phosphorous in 0-300 cm soil layer was 3.30-6.42 mg.kg-1, being moderate in upper soil layer and scarce in deep soil layer. The content of available potassium in 0-300 cm soil layer was 78.09-98.31 mg.kg-1, presenting abundant. The contents of nutrients were all higher in 0-100 cm soil layer than in 100-300 cm soil layer. The soil organic matter and total and available nitrogen contents and the soil nutrient index (SNI) all presented a trend of decrease after an initial increase with the increasing apple tree age. The contents of the test nutrients except total potassium in 0-100 cm soil layer all decreased rapidly with soil depth, while those in deeper soil layers kept relatively stable. There existed significant correlations between the contents of soil organic matter, total nitrogen, available nitrogen, total phosphorous

  18. Changes in Organic Carbon Index of Grey Desert Soil in Northwest China After Long-Term Fertilization

    Institute of Scientific and Technical Information of China (English)

    XU Yong-mei; LIU Hua; WANG Xi-he; XU Ming-gang; ZHANG Wen-ju; JIANG Gui-ying

    2014-01-01

    Soil organic carbon (SOC), soil microbial biomass carbon (SMBC) and SMBC quotient (SMBC/SOC, qSMBC) are key indexes of soil biological fertility because of the relationship to soil nutrition supply capacity. Yet it remains unknown how these three indexes change, which limits our understanding about how soil respond to different fertilization practices. Based on a 22-yr (1990-2011) long-term fertilization experiment in northwest China, we investigated the dynamics of SMBC and qSMBC during the growing period of winter wheat, the relationships between the SMBC, qSMBC, soil organic carbon (SOC) concentrations, the carbon input and grain yield of wheat as well. Fertilization treatments were 1) nonfertilization (control);2) chemical nitrogen plus phosphate plus potassium (NPK);3) NPK plus animal manure (NPKM);4) double NPKM (hNPKM) and 5) NPK plus straw (NPKS). Results showed that the SMBC and qSMBC were signiifcantly different among returning, jointing, lfowering and harvest stages of wheat under long-term fertilization. And the largest values were observed in the lfowering stage. Values for SMBC and qSMBC ranged from 37.5 to 106.0 mg kg-1 and 0.41 to 0.61%, respectively. The mean value rank of SMBC during the whole growing period of wheat was hNPKM>NPKM>NPKS>CK>NPK. But there were no statistically signiifcant differences between hNPKM and NPKM, or between CK and NPK. The order for qSMBC was NPKS>NPKM>CK>hNPKM>NPK. These results indicated that NPKS signiifcantly increased the ratio of SMBC to SOC, i.e., qSMBC, compared with NPK fertilizer or other two NPKM fertilizations. Signiifcant linear relationships were observed between the annual carbon input and SOC (P<0.01) or SMBC (P<0.05), and between the relative grain yield of wheat and the SOC content as well (P<0.05). But the qSMBC was not correlated with the annual carbon input. It is thus obvious that the combination of manure, straw with mineral fertilizer may be beneift to increase SOC and improve soil quality than

  19. [Effects of revegetation on organic carbon storage in deep soils in hilly Loess Plateau region of Northwest China].

    Science.gov (United States)

    Zhang, Jin; Xu, Ming-Xiang; Wang, Zheng; Ma, Xin-Xin; Qiu, Yu-Jie

    2012-10-01

    Taking the Robinia pseudoacacia woodlands, Caragana korshinskii shrublands, and abandoned croplands with different years of revegetation in the hilly Loess Plateau region of Northwest China as test objects, this paper studied the profile distribution and accumulation dynamics of organic carbon storage in deep soil (100-400 cm), with those in 0-100 cm soil profile as the control. In 0-100 cm soil profile, the organic carbon storage decreased significantly with the increase of soil depth; while in deep soil, the organic carbon storage had a slight fluctuation. The total organic carbon storage in 100-400 cm soil profile was considerably high, accounting for approximately 60% of that in 0-400 cm soil profile. The organic carbon storage in 80-100 cm soil layer had a significant linear correlation with that in 100-200 and 200-400 cm soil layers, and among the organic carbon storages in the five layers in 0-100 cm soil profile, the organic carbon storage in 80-100 cm soil layer had the strongest correlation with that in 100-400 cm soil profile, being able to be used to estimate the organic carbon storage in deep soil in this region. The organic carbon storage in 0-20 cm soil layer in the three types of revegetation lands was significantly higher than that in slope croplands, but the organic carbon storage in deep soil had no significant difference among the land use types. The organic carbon storage in deep soil increased with the increasing years of revegetation. In R. pseudoacacia woodlands and C. korshinskii shrub lands, the average increasing rate of the organic carbon storage in 100-400 cm soil layer was 0.14 and 0.19 t x hm(-2) x a(-1), respectively, which was comparable to that in the 0-100 cm soil layer in C. korshinskii shrublands. It was suggested that in the estimation of the soil carbon sequestration effect of revegetation in hilly Loess Plateau region, the organic carbon accumulation in deep soil should be taken into consideration. Otherwise, the effect of

  20. Non-methane hydrocarbons (NMHCs) and their contribution to ozone formation potential in a petrochemical industrialized city, Northwest China

    Science.gov (United States)

    Jia, Chenhui; Mao, Xiaoxuan; Huang, Tao; Liang, Xiaoxue; Wang, Yanan; Shen, Yanjie; Jiang, Wanyanhan; Wang, Huiqin; Bai, Zhilin; Ma, Minquan; Yu, Zhousuo; Ma, Jianmin; Gao, Hong

    2016-03-01

    Hourly air concentrations of fifty-three non-methane hydrocarbons (NMHCs) were measured at downtown and suburb of Lanzhou, a petrochemical industrialized city, Northwest China in 2013. The measured data were used to investigate the seasonal characteristics of NMHCs air pollution and their contributions to the ozone formation in Lanzhou. Annually averaged NMHCs concentration was 38.29 ppbv in downtown Lanzhou. Among 53 NMHCs, alkanes, alkenes, and aromatics accounted for 57%, 23% and 20% of the total NMHCs air concentration, respectively. The atmospheric levels of toluene and propane with mean values of 4.62 and 4.56 ppbv were higher than other NMHCs, respectively. The ambient levels of NMHCs in downtown Lanzhou were compared with measured NMHCs data collected at a suburban site of Lanzhou, located near a large-scale petrochemical industry. Results show that the levels of alkanes, alkenes, and aromatics in downtown Lanzhou were lower by factors of 3-11 than that in west suburb of the city. O3-isopleth plots show that ozone was formed in VOCs control area in downtown Lanzhou and NOx control area at the west suburban site during the summertime. Propylene-equivalent (Prop-Equiv) concentration and the maximum incremental reactivity (MIR) in downtown Lanzhou indicate that cis-2-butene, propylene, and m/p-xylene were the first three compounds contributing to ozone formation potentials whereas in the petrochemical industrialized west suburb, ethane, propene, and trans-2-Butene played more important role in the summertime ozone formation. Principal component analysis (PCA) and multiple linear regression (MLR) were further applied to identify the dominant emission sources and examine their fractions in total NMHCs. Results suggest that vehicle emission, solvent usage, and industrial activities were major sources of NMHCs in the city, accounting for 58.34%, 22.19%, and 19.47% of the total monitored NMHCs in downtown Lanzhou, respectively. In the west suburb of the city

  1. Chemical composition, sources, and processes of urban aerosols during summertime in Northwest China: insights from High Resolution Aerosol Mass Spectrometry

    Science.gov (United States)

    Xu, J.; Zhang, Q.; Chen, M.; Ge, X.; Ren, J.; Qin, D.

    2014-06-01

    An aerodyne High Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) was deployed along with a Scanning Mobility Particle Sizer (SMPS) and a Multi Angle Absorption Photometers (MAAP) to measure the temporal variations of the mass loading, chemical composition, and size distribution of sub-micrometer particulate matter (PM1) in Lanzhou, northwest China, during 12 July-7 August 2012. The average PM1 mass concentration including non-refractory PM1 (NR-PM1) measured by HR-ToF-AMS and black carbon (BC) measured by MAAP during this study was 24.5 μg m-3 (ranging from 0.86 to 105μg m-3), with a mean composition consisting of 47% organics, 16% sulfate, 12% BC, 11% ammonium, 10% nitrate, and 4% chloride. The organics was consisted of 70% carbon, 21% oxygen, 8% hydrogen, and 1% nitrogen, with the average oxygen-to-carbon ratio (O / C) of 0.33 and organic mass-to-carbon ratio (OM / OC) of 1.58. Positive matrix factorization (PMF) of the high-resolution mass spectra of organic aerosols (OA) identified four distinct factors which represent, respectively, two primary OA (POA) emission sources (traffic and food cooking) and two secondary OA (SOA) types - a fresher, semi-volatile oxygenated OA (SV-OOA) and a more aged, low-volatility oxygenated OA (LV-OOA). Traffic-related hydrocarbon-like OA (HOA) and BC displayed distinct diurnal patterns both with peak at ~07:00-11:00 (BJT: UTC +8) corresponding to the morning rush hours, while cooking OA (COA) peaked during three meal periods. The diurnal profiles of sulfate and LV-OOA displayed a broad peak between ∼07:00-15:00, while those of nitrate, ammonium, and SV-OOA showed a narrower peak at ~08:00-13:00. The later morning and early afternoon peak in the diurnal profiles of secondary aerosol species was likely caused by mixing down of pollutants aloft, which were likely produced in the residual layer decoupled from the boundary layer during night time. The mass spectrum of SV-OOA also showed similarity with that of

  2. Potassium channel changes of peripheral blood T-lymphocytes from Kazakh hypertensive patients in Northwest China and the inhibition effect towards potassium channels by telmisartan.

    Science.gov (United States)

    Zhang, Qiubing; Gou, Fang; Zhang, Yuanming; He, Yuanjun; He, Jixian; Peng, Ling; Cheng, Lufeng; Yuan, Qingyan; Zhang, Guiming; Huang, Shasha

    Increasing evidence indicates that chronic inflammation is a direct or indirect manifestation of hypertension. Potassium channels are thought to be critical for lymphocyte activation, which suggests that hypertension may be an inflammatory disease initiated at the ion channel level. This study investigated changes in interleukin (IL)-6, IL-17, and transforming growth factor beta (TGF-b1) expression in the blood of Kazakh hypertensive patients in Northwest China using ELISA technology. Whole-cell patch clamp technology was used to evaluate current changes associated with Kv1.3 and KCa3.1 in peripheral blood T lymphocytes of hypertensive patients, and to investigate current changes induced by telmisartan. We also investigated the effects of telmisartan on expression of Kv1.3 and KCa3.1 at mRNA and protein levels in peripheral blood T lymphocytes using real-time polymerase chain reaction and Western blot analysis. Expression of IL-6, IL-17 and TGF-b1 in the blood of Kazakh hypertensive patients in Northwest China was significantly higher than in healthy controls (p Telmisartan intervention for 24 h and 48 h inhibited the current and expression of Kv1.3 and KCa3.1 at mRNA and protein levels (p telmisartan, resulting in a reduced inflammatory response. These results provide theoretical support for the treatment of hypertension at the cellular ion channel level.

  3. Integrated water resources management and water users' associations in the arid region of northwest China: a case study of farmers' perceptions.

    Science.gov (United States)

    Hu, Xiao-Jun; Xiong, You-Cai; Li, Yong-Jin; Wang, Jian-Xin; Li, Feng-Min; Wang, Hai-Yang; Li, Lan-Lan

    2014-12-01

    Water scarcity is a critical policy issue in the arid regions of northwest China. The local government has widely adopted integrated water resources management (IWRM), but lacks support from farmers and farm communities. We undertook a case study in the Minqin oasis of northwest China to examine farmers' responses to IWRM and understand why farmer water users' associations (WUAs) are not functioning effectively at the community level. Results of quantitative and qualitative surveys of 392 farmers in 27 administrative villages showed that over 70% of farmers disapprove of the IWRM market-based reforms. In particular, the failure of farmer WUAs can be attributed to overlapping organizational structures between the WUAs and the villagers' committees; mismatches between the organizational scale of the WUAs and practical irrigation management by the farmers themselves; marginalization of rural women in water decision-making processes; and the inflexibility of IWRM implementation. An important policy implication from this study is that rebuilding farmer WUAs is key to overcoming the difficulties of IWRM. The current water governance structure, which is dominated by administrative systems, must be thoroughly reviewed to break the vicious cycle of tension and distrust between farmers and the government.

  4. Investigating the Impact of Shading Effect on the Characteristics of a Large-Scale Grid-Connected PV Power Plant in Northwest China

    Directory of Open Access Journals (Sweden)

    Yunlin Sun

    2014-01-01

    Full Text Available Northwest China is an ideal region for large-scale grid-connected PV system installation due to its abundant solar radiation and vast areas. For grid-connected PV systems in this region, one of the key issues is how to reduce the shading effect as much as possible to maximize their power generation. In this paper, a shading simulation model for PV modules is established and its reliability is verified under the standard testing condition (STC in laboratory. Based on the investigation result of a 20 MWp grid-connected PV plant in northwest China, the typical shading phenomena are classified and analyzed individually, such as power distribution buildings shading and wire poles shading, plants and birds droppings shading, and front-row PV arrays shading. A series of experiments is also conducted on-site to evaluate and compare the impacts of different typical shading forms. Finally, some feasible solutions are proposed to avoid or reduce the shading effect of PV system during operation in such region.

  5. Application of valve-regulated lead-acid batteries for storage of solar electricity in stand-alone photovoltaic systems in the northwest areas of China

    Science.gov (United States)

    Hua, Shounan; Zhou, Qingshen; Kong, Delong; Ma, Jianping

    Photovoltaic (PV) installations for solar electric power generation are being established rapidly in the northwest areas of China, and it is increasingly important for these power systems to have reliable and cost effective energy storage. The lead-acid battery is the more commonly used storage technology for PV systems due to its low cost and its wide availability. However, analysis shows that it is the weakest component of PV power systems. Because the batteries can be over discharged, or operated under partial state of charge (PSOC), their service life in PV systems is shorter than could be expected. The working conditions of batteries in remote area installations are worse than those in situations where technical support is readily available. Capacity-loss in lead-acid batteries operated in remote locations often occurs through sulfation of electrodes and stratification of electrolyte. In northwest China, Shandong Sacred Sun Power Sources Industry Co. Ltd. type GFMU valve-regulated lead-acid (VRLA) batteries are being used in PV power stations. These batteries have an advanced grid structure, superior leady paste, and are manufactured using improved plate formation methods. Their characteristics, and their performance in PV systems, are discussed in this paper. The testing results of GFMU VRLA batteries in the laboratory have shown that the batteries could satisfy the demands of the International Electrotechnical Commission (IEC) standards for PV systems.

  6. Research on the Tourism Competitiveness of Qinghai in Northwest China%青海省在西北地区的旅游竞争力研究

    Institute of Scientific and Technical Information of China (English)

    罗正霞; 李玲琴; 李春花; 卓玛措; 黄芸玛

    2009-01-01

    Using Porter's diamond model, AHP method and SPSS statistical software,a comprehensive evaluation was made on the tourism industry in different provinces of Northwest China, based on analyzing the tourism reality competitiveness, potential competitiveness, supporting competitiveness, regional economic conditions and the overall competitiveness.Meanwhile,the tourism status of Qinghai in Northwest China was deeply analyzed and some appropriate countermeasures for enhancing its tourism competitiveness were put forward.%基于波特钻石模型,采用层次分析法,借助SPSS统计软件对西北各省旅游业现实竞争力、支持竞争力、潜在竞争力、区域经济条件及综合竞争力做出综合评价,深入分析青海省旅游业在西北地区的地位并指出提升青海省旅游竞争力的相应对策.

  7. 西北地区抽水蓄能发展研究%Research on Development of Pumped-Storage Hydropower in Northwest of China

    Institute of Scientific and Technical Information of China (English)

    贾德香; 程路

    2012-01-01

    With the large-scale development of wind power in Northwest China, the feasibility for building pumped-storage plants in this area needs to be studied to facilitate the effective consumption of wind power. The principle and method for planning pumped-storage plants are proposed. Considering the traditional hydropower development and the planned sites of pumped-storage plants, with the aim of minimum total social cost of the power supply, and with multiple factors such as the effective consumption of wind power and the balance of power and energy as constraints, the paper proposes a rational and feasible development scale and the distribution of pumped-storage plants in Northwest China, which can provide a reference for the formulation of development planning and management measures of pumped-storage power stations for the northwest grid.%面对我国西北地区未来风电大规模开发趋势,需要深入研究西北地区建设抽水蓄能电站的可行性,以便促进风电有效消纳.提出了抽水蓄能电站发展研究的思路、原则和方法,结合常规水电开发和抽蓄电站选点,以全社会电力供应总成本最低为目标,以清洁能源有效消纳和电力电量平衡等多种因素为约束条件,提出了西北地区抽水蓄能电站的合理可行的开发规模、布局,为西北电网制定抽水蓄能发展规划和管理措施提供参考.

  8. Chemical composition, sources, and processes of urban aerosols during summertime in Northwest China: insights from High Resolution Aerosol Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    J. Xu

    2014-06-01

    Full Text Available An aerodyne High Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS was deployed along with a Scanning Mobility Particle Sizer (SMPS and a Multi Angle Absorption Photometers (MAAP to measure the temporal variations of the mass loading, chemical composition, and size distribution of sub-micrometer particulate matter (PM1 in Lanzhou, northwest China, during 12 July–7 August 2012. The average PM1 mass concentration including non-refractory PM1 (NR-PM1 measured by HR-ToF-AMS and black carbon (BC measured by MAAP during this study was 24.5 μg m−3 (ranging from 0.86 to 105μg m−3, with a mean composition consisting of 47% organics, 16% sulfate, 12% BC, 11% ammonium, 10% nitrate, and 4% chloride. The organics was consisted of 70% carbon, 21% oxygen, 8% hydrogen, and 1% nitrogen, with the average oxygen-to-carbon ratio (O / C of 0.33 and organic mass-to-carbon ratio (OM / OC of 1.58. Positive matrix factorization (PMF of the high-resolution mass spectra of organic aerosols (OA identified four distinct factors which represent, respectively, two primary OA (POA emission sources (traffic and food cooking and two secondary OA (SOA types – a fresher, semi-volatile oxygenated OA (SV-OOA and a more aged, low-volatility oxygenated OA (LV-OOA. Traffic-related hydrocarbon-like OA (HOA and BC displayed distinct diurnal patterns both with peak at ~07:00–11:00 (BJT: UTC +8 corresponding to the morning rush hours, while cooking OA (COA peaked during three meal periods. The diurnal profiles of sulfate and LV-OOA displayed a broad peak between ∼07:00–15:00, while those of nitrate, ammonium, and SV-OOA showed a narrower peak at ~08:00–13:00. The later morning and early afternoon peak in the diurnal profiles of secondary aerosol species was likely caused by mixing down of pollutants aloft, which were likely produced in the residual layer decoupled from the boundary layer during night time. The mass spectrum of SV-OOA also showed similarity

  9. Organic petrology and geochemistry of mudrocks from the lacustrine Lucaogou Formation, Santanghu Basin, northwest China: Application to lake basin evolution

    Science.gov (United States)

    Hackley, Paul C.; Fishman, Neil; Wu, Tao; Baugher, Gregory

    2016-01-01

    Exploration for tight oil in the frontier Santanghu Basin of northwest China has resulted in recent commercial discoveries sourced from the lacustrine Upper Permian Lucaogou Formation, already considered a “world class source rock” in the Junggar Basin to the west. Here we apply an integrated analytical program to carbonate-dominated mudrocks from the Lucaogou Formation in Santanghu Basin to document the nature of organic matter (OM) in the context of an evolving lake system. The organic-rich samples (TOC 2.8–11.4 wt%; n = 10) were widely spaced from an ~ 200 m cored section, interpreted from textural and mineralogical evidence to document transition from a lower under-filled to an overlying balanced-filled lake. Organic matter is dominated by moderate to strongly fluorescent amorphous material with Type I geochemical signature (HI values 510–755; n = 10) occurring in a continuum from lamellar stringers, 10–20 μm thick, some ≥ 1 mm in length (possible microbial mat; preserved only in lower under-filled section) to finely-disseminated amorphous groundmass intimately intermixed with mineral matrix. Biomarkers for methanotrophs and photosynthetic cyanobacteria indicate a complex microbial consortium. A unicellular prasinophyte green alga(?), similar to Tasmanites in marine rocks, is present as discrete flattened discs 50–100 μm in diameter. Type III OM including vitrinite (some fluorescent) and inertinite also is abundant. Solid bitumen, indicating local kerogen conversion, fills voids and occurs throughout the cored section. Vitrinite reflectance values are 0.47–0.58%, consistent with strong OM fluorescence but may be “suppressed”. Other proxies, e.g., biomarker parameters, indicate the Lucaogou Formation is in the early oil window at this location. On average, slightly more amorphous OM and telalginite are present in the lower section, consistent with a shallow, stratified, saline environment with low sediment dilution. More

  10. Reservoir microfacies and their logging response of gas hydrate in the Qilian Mountain permafrost in Northwest China

    Science.gov (United States)

    Liu, H.; Lu, Z.; Zhang, Y.; Sun, Z.

    2012-12-01

    The Qilian Mountain permafrost is located in the north margin of the Qinghai-Tibet Plateau in northwest China. The permafrost area is about 10×104 Km2, and dominated by mountain permafrost. The mean annual ground temperature is 1.5 to 2.4 centigrade and the thickness of permafrost is generally 50 to 139 m. The gas hydrate was sampled successfully in the 133-396m interval from holes DK-1, DK-2 and DK-3 and tested by microRaman spectroscopy in the hydrate laboratory of the Qingdao Institute of Marine Geology during June to September in 2009. The exploratory drilling indicated that gas hydrate and its abnormal occurrence are mainly developed 130-400 m beneath permafrost. The strata belong to the Jiangcang Formation of middle Jurassic. Based on lithology, sedimentary structure and sequence and other facies markers, reservoir microfacies of gas hydrate are identified as underwater distributary channel and interdistributary bay in delta front of delta and deep lake mudstone facies in lacustrine. The underwater distributary channel in delta front of delta is dominated by fine sandstone. It has little mudstone. The grain size generally becomes finer, and scour-filling structure, parallel bedding, cross bedding and wavy bedding develop successively from bottom to top in one phase of channel. In vertical multi-period distributary channels superimpose, forming thick sandstone, and sometimes a thin mudstone develop between two channels. The interdistributaty bay is characterized by mudstone with little siltstone and fine sandstone. The lithology column shows mudstone interbedded with thin sandstone. Horizon bedding and lenticular bedding are the main structure. The gas hydrate usually presents visible white (smoky gray when mixing with mud) ice-like lamina in fissures or invisible micro disseminated occurrence in pores of sandstone. Honeycomb pores formed by the decomposition of gas hydrate are usually found in sandstone. The deep lake is dominated by thick dark grey mudstone

  11. Bulk transfer coefficients of the atmospheric momentum and sensible heat over desert and Gobi in arid climate region of Northwest China

    Institute of Scientific and Technical Information of China (English)

    张强; 卫国安; 黄荣辉; 曹晓彦

    2002-01-01

    By utilizing the data of the intensive observation period (May-June, 2000) of Dunhuang land-surface process field experiment that belongs to "Land-atmosphere Interactive Field Experiment over Arid Region of Northwest China", the bulk momentum transfer coefficient Cd and bulk sensible heat transfer coefficient Ch between surface and atmosphere over desert and Gobi in the arid region are determined according to three different methods. The result shows that, though these bulk transfer coefficients are different, they are in the same order. Especially, the means of Cd and Ch are close. Moreover, through analyzing the wind direction, the interference of the building near the observational station with the data is eliminated. From this, the relation between the bulk transfer coefficients and the bulk Richardson number and the range of the typical values of the bulk transfer coefficients over desert and Gobi in the typical arid region are obtained.

  12. Genesis Analysis of High-Gamma Ray Sandstone Reservoir and Its Log Evaluation Techniques: A Case Study from the Junggar Basin, Northwest China

    Directory of Open Access Journals (Sweden)

    Liang Wang

    2013-01-01

    Full Text Available In the Junggar basin, northwest China, many high gamma-ray (GR sandstone reservoirs are found and routinely interpreted as mudstone non-reservoirs, with negative implications for the exploration and exploitation of oil and gas. Then, the high GR sandstone reservoirs’ recognition principles, genesis, and log evaluation techniques are systematically studied. Studies show that the sandstone reservoirs with apparent shale content greater than 50% and GR value higher than 110API can be regarded as high GR sandstone reservoir. The high GR sandstone reservoir is mainly and directly caused by abnormally high uranium enrichment, but not the tuff, feldspar or clay mineral. Affected by formation’s high water sensitivity and poor borehole quality, the conventional logs can not recognize reservoir and evaluate the physical property of reservoirs. Then, the nuclear magnetic resonance (NMR logs is proposed and proved to be useful in reservoir recognition and physical property evaluation.

  13. Study of impacts of floods on the water quality in an arid zone: the case of the Tarim River in Northwest China.

    Science.gov (United States)

    Jean de la Paix, Mupenzi; Lanhai, Li; Xi, Chen; Varenyam, Achal; Anming, Bao

    2011-01-01

    This paper presents the results of the study undertaken at the Tarim River Basin in Northwest China to analyze impacts of flooding on water quality. It was shown that irregular rainfall was the cause of flash floods that affected many ecosystems and eroded soils. Simulation results and the existence of relationships between flood volume and flood peak allowed potential model application that included flood peak estimation. The analysis of water pollution through sample sediment was helped by spectroscopy techniques and it was found that the flood was the main cause of many chemical elements in water. The floods affected the quality of water in the Tarim River where it was slightly basic with pH = 8.1 before flooding and acidic with pH = 6.9 after flooding.

  14. Evaluation of the pollution and human health risks posed by heavy metals in the atmospheric dust in Ebinur Basin in Northwest China.

    Science.gov (United States)

    Abuduwailil, Jilili; Zhaoyong, Zhang; Fengqing, Jiang

    2015-09-01

    Recently, a large amount of research assessing pollution levels and the related health risks posed by atmosphere dust has been undertaken worldwide. However, little work has been done in the oases of the arid regions of Northwest China. In this paper, we studied the pollution and health risks over a year of seven heavy metals in the atmospheric dust of Ebinur Basin, a typical oasis in Northwest China. The results showed the following: (1) The annual amount of atmospheric deposition in Ebinur Basin was 298.23 g m(-2) and the average monthly atmospheric deposition was 25.06 g m(-2). The average and maximum values of the seven heavy metals measured were all below the National Soil Environmental Quality Standards (2nd). (2) Heavy metals of Cu, Cr, and As in the atmospheric deposition mainly originated from the natural geological background, while Zn came from human activity. This study also showed that among the seven measured heavy metals, the ratios of the no-pollution status of Pb, Cd, and Hg were higher than those of others with moderate degrees of pollution also accounting for a certain ratio. (3) The carcinogenic risks from As, Cd, and Cr were all lower than the corresponding standard limit values, and these metals are considered not harmful to the health of the basin. However, there is a relatively high risk of exposure for children from hand-to-mouth intake, which is worthy of attention. This research showed that both human activity and natural factors, such as wind and altitude, influenced the heavy metal contents in the atmospheric dust of the study area. Furthermore, recent human activity in the study area had the most negative influence on the accumulation of the heavy metals and the corresponding health risks, especially for Hg, Pb, and Cd, which is worthy of attention.

  15. Causes of Sandstorm Disaster and Strategies against Desertification——A Case Study of Hexi Corridor in Northwest China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This case study outlines the problems faced by the peoples of the Hexi Corridor. These problems are serious and urgent, and are representative of those faced by other communities right across western China. The root causes are outlined and some remedies are suggested. The practical measures proposed under China's National Action Plan to Combat Desertification are described and discussed.

  16. Organic geochemistry and hydrocarbon potential contrasts among lithologically different source rocks in the Qingxi Sag, Jiuquan Basin, Northwest China

    Science.gov (United States)

    Zhang, Weiwei; Huang, Zhilong; Gao, Gang; Yin, Yue; Li, Tianjun

    2017-04-01

    Jiuquan Basin, located in the eastern part of Hexi Corridor, is a medium- to small-sized superimposed basin in northwest China. Situated in the southwest of the basin is the Qingxi sag, in which the development of large sets of argillaceous dolomite dominate (lithological assemblage named as LSA) and dolomitic mudstone (LSB), partially being mudstone. From electronical and seismic profile features, the Lower Cretaceous can be divided into the Chijinpu Formation, Xiagou Formation, and Zhonggou Formation in the Qingxi Sag. Moreover, the Xiagou Formation can be divided into four members, represented as K1g0, K1g1, K1g2, and K1g3. The given lithological assemblages and occurrence of particular mineralogical combinations indicate that it is the product of hydrothermal deposition. Lithologically, the argillaceous dolomite and dolomitic mudstone are diametrically different in both mineral contents and types. The integration of field outcrop observation and sampling with laboratory analyses, including solvent extract, Rock-Eval (S1, S2, and Tmax), organic petrography (lithological identification, cement, grain, mineral, and maceral observation), and laboratory modeling of hydrocarbon generation, show that both LSA and LSB contains good hydrocarbon potentials but rather different mineralogical compositions. The concurrence of LSA and LSB indicates the alternate interaction between the hydrothermal deposition and normal lacustrine deposits. The LSA mainly contains Type I kerogen and much lower Pr/Ph ratio, indicating parental material sourced from lacustrine algae and bacteria and much stronger reduction depostional environment. However, the LSB mainly contains Type III kerogen, containing parental material mainly sourced from terrestrial higher plant. And in the mudstone, there is almost no Type I kerogen, indicating no substantial input of lacustrine phytoplankton. The LSA contains TOC value of 1.2-3.2% (wt), averaging 2.1% (wt); while the LSB contains 0.8-2.4% (wt) with

  17. Effects of Ethnic Settlements and Land Management Status on Species Distribution Patterns: A Case Study of Endangered Musk Deer (Moschus spp. in Northwest Yunnan, China.

    Directory of Open Access Journals (Sweden)

    Xueyou Li

    Full Text Available Understanding the status and spatial distribution of endangered species in biologically and ethnologically diverse areas is important to address correlates of cultural and biological diversity. We developed models for endangered musk deer (Moschus spp. abundance indices in and around protected areas inhabited by different ethnic groups in northwest Yunnan China to address different anthropogenic and management-related questions. We found that prediction of relative abundance of musk deer was best accomplished using ethnicity of settlements, conservation status and poaching pressure in an area. Musk deer were around 5 times more abundant in Tibetan regions relative to Lisu regions. We found no significant negative correlates of gathering and transhumance activities on musk deer abundance. Hunting pressure showed no significant differences between protected and non-protected areas, but showed significant differences among ethnic groups. Hunting pressures in areas adjacent to Lisu settlements was 7.1 times more than in areas adjacent to Tibetan settlements. Our findings indicate protected areas in southwest China are not fully effective in deterring human disturbance caused by traditional practices. We suggest that conservation and management strategies should engage traditional culture and practices with a positive conservation impact. Better understanding of indigenous culture may open up new opportunities for species conservation in much wider tracts of unprotected and human-dominated lands. Traditional practices that are not destructive to biodiversity should be allowed as a way of providing a link between the local communities and protected areas thereby creating incentives for conservation.

  18. Water resources utilization and eco-environmental safety in Northwest China%中国西北水资源利用及生态环境安全

    Institute of Scientific and Technical Information of China (English)

    张济世; 徐进祥; 张永秋

    2006-01-01

    Northwest China includes Xinjiang Ugyur Autonomous Region, Qinghai Province, Gansu Province, Ningxia Hui Autonomous Region and Shaanxi Province, covering 308× 104 km2. It is located in the warm-temperate zone and the climate is arid or semi-arid. Precipitation is very scarce but evaporation is extremely high. The climate is dry, the water resources are deficient, the eco-environment is fragile, and the distribution of water resources is uneven. In this region, precipitation is the only input, and evaporation is the only output in the inland rivers, and precipitation, surface water and groundwater change with each other for many times, which benefits the storage and utilization of water resources.The average precipitation in this region is 232 mm, the total precipitation amount is 7003 × 108 m3/a,the surface water resources are 1891 × 108 m3/a, the total natural groundwater resources are 1150× 108 m3/a,the total available water resources are 438 × 108 m3/a, and the total water resources are 1996× 108 m3/a and per capita water resources are 2278 m3/a. The water resources of the whole area are 5.94× 104 m3/(a.km2),being only one-fifth of the mean value in China. Now, the available water resources are 876×108 m3/a,among which groundwater is proximate 130× 108 m3/a.

  19. Retrieval of precipitable water vapor using MFRSR and comparison with other multisensors over the semi-arid area of northwest China

    Science.gov (United States)

    Li, Xia; Zhang, Lei; Cao, Xianjie; Quan, Jiannong; Wang, Tianhe; Liang, Jiening; Shi, Jinsen

    2016-05-01

    Precipitable water vapor (PWV) was retrieved using direct solar irradiance at 938 nm measured by a multifilter rotating shadowband radiometer (MFRSR) at the Semi-Arid Climate and Environment Observatory of Lanzhou University (SACOL) located in the semi-arid area of northwest China from August 2007 to June 2010. Measurement also occurred at Zhangye, China, at the Atmosphere Radiation Measurements (ARM) Program's Ancillary Facility during the dust period from April to June 2008. The line-by-line radiative transfer model (LBLRTM) code combined with the HITRAN 2004 spectral database is used to model the water vapor spectral transmittance throughout the 938-nm spectral response of MFRSR in the retrieval algorithm. Gaussian fitting is proposed to determine the daily calibration constant at the top of atmosphere for a long-term series under an obvious annual change in solar radiation. PWV retrieved by MFRSR over SACOL shows that 90% of PWV values are smaller than 1.52 cm, and PWV distribution has a seasonal variation, with maximum in summer and minimum in winter. The comparisons between MFRSR and other measurements show a better agreement between MFRSR and sunphotometer (AERONET's Cimel) PWV retrievals with relative bias of 2.9% and RMS difference of 9.1% than between MFRSR and microwave radiometer (MWR) with relative bias of 10% and RMS difference of 23% over SACOL, and an excellent agreement between MFRSR and sunphotometer with relative bias of 0.56% and RMS difference of 6.1% over Zhangye. To verify satellite PWV products over the semi-arid area of northwest China, the comparisons of PWV from MODIS and AIRS with MFRSR suggest that the agreement between satellite and MFRSR PWV retrievals is not as good as that between MFRSR and other ground-based instruments. MODIS appears to slightly underestimate PWV in a dry atmosphere but overestimate PWV in a moist atmosphere against MFRSR. A method is proposed to correct MODIS PWV products. AIRS PWV products relative to MFRSR show

  20. Toxoplasma gondii, Dirofilaria immitis, feline immunodeficiency virus (FIV), and feline leukemia virus (FeLV) infections in stray and pet cats (Felis catus) in northwest China: co-infections and risk factors.

    Science.gov (United States)

    Cong, Wei; Meng, Qing-Feng; Blaga, Radu; Villena, Isabelle; Zhu, Xing-Quan; Qian, Ai-Dong

    2016-01-01

    This study was conducted to estimate the prevalence of Toxoplasma gondii, Dirofilaria immitis, feline immunodeficiency virus (FIV), and feline leukemia virus (FeLV) infections among stray and pet cats in Lanzhou, northwest China, and to identify the influence of age, gender, and regions on seropositivity. T. gondii antibodies were examined in cat sera by the modified agglutination test (MAT). The circulating antigens of D. immitis and FeLV and specific antibodies to FIV were examined using kits commercially available. The overall prevalence of T. gondii, FIV, FeLV, and D. immitis was 19.34, 9.12, 11.33, and 3.04 %, respectively. For the genetic characterization of T. gondii genotypes in cats, genomic DNA was extracted from the seropositive cats and the T. gondii B1 gene was amplified using a semi-nested PCR. DNA samples giving positive B1 amplification were then genotyped using multilocus PCR-RFLP. Two T. gondii genotypes (ToxoDB#9 and ToxoDB#1) were identified. Results of the multivariate logistic regression analysis showed that older cats are more likely to be seropositive than juveniles for T. gondii, FIV, FeLV, and D. immitis. This is the first report of T. gondii genotypes in cats in northwest China. Moreover, the present study is the first study of retrovirus and D. immitis seroprevalence in cats in China. The results revealed that T. gondii, FIV, and FeLV infections are common in stray and pet cats in northwest China.

  1. Ethnic stratification in northwest China: occupational differences between Han Chinese and national minorities in Xinjiang, 1982-1990.

    Science.gov (United States)

    Hannum, E; Xie, Y

    1998-08-01

    The debate on market reforms and social stratification in China has paid very little attention to China's ethnic minorities. We explored rising occupational stratification by ethnicity in the Xinjiang Uygur Autonomous Region. Analyses of census data from 1982 and 1990 pointed to educational disadvantages faced by ethinic minorities as the most plausible explanation for the change. Multivariate analysis revealed a significant increase in the effect of education on high-status occupational attainment but no change in the effect of ethnicity. Net of education, ethnic differences in high-status occupational attainment were negligible. In contrast, large ethnic differences in manufacturing and agricultural occupations persisted after education and geography were statistically controlled.

  2. CLPTM1L genetic polymorphisms and interaction with smoking and alcohol drinking in lung cancer risk: a case-control study in the Han population from northwest China.

    Science.gov (United States)

    Xun, Xiaojie; Wang, Huijuan; Yang, Hua; Wang, Hong; Wang, Bo; Kang, Longli; Jin, Tianbo; Chen, Chao

    2014-12-01

    Genetic variants of cleft lip and palate trans-membrane 1-like (CLPTM1L) genes in the p15.33 region of chromosome 5 were previously identified to influence susceptibility to lung cancer. We examined the association of single nucleotide polymorphisms (SNPs) in CLPTM1L genes with lung cancer and explored their potential effects on the relationship between environmental risk factors (smoking, drinking) and lung cancer in a Chinese Han population. We genotyped 9 single nucleotide polymorphisms (SNPs) of CLPTM1L in a case-control study with 228 lung cancer cases and 301 controls from northwest China. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by unconditional logistic regression. We identified that the minor alleles of rs451360, rs402710, and rs31484 in CLPTM1L were associated with a 0.52-fold, 0.76-fold, and 0.70-fold decreased risk of lung cancer in allelic model analysis, respectively. In the genetic model analysis, we found rs402710 and rs401681 were associated with decreased lung cancer risk. Further stratification analysis showed that rs380286 displayed a significantly decreased lung cancer risk (OR=0.65, P=0.041) in the non-drinkers. In addition, Haplotype "GTTATCTGT" was found to be associated with decreased lung cancer risk (OR=0.50, P=0.033). Our results verified that genetic variants of CLPTM1L contribute to lung cancer susceptibility in the northwest Chinese Han population. Additionally, we found that consumption of alcohol may interact with CLPTM1L polymorphisms to contribute to overall lung cancer susceptibility.

  3. Post-Triassic thermal history of the Tazhong Uplift Zone in the Tarim Basin, Northwest China: Evidence from apatite fission-track thermochronology

    Directory of Open Access Journals (Sweden)

    Caifu Xiang

    2013-11-01

    Full Text Available The Tarim Basin is a representative example of the basins developed in the northwest China that are characterized by multiple stages of heating and cooling. In order to better understand its complex thermal history, apatite fission track (AFT thermochronology was applied to borehole samples from the Tazhong Uplift Zone (TUZ. Twelve sedimentary samples of Silurian to Triassic depositional ages were analyzed from depths coinciding with the apatite partial annealing zone (∼60–120 °C. The AFT ages, ranging from 132 ± 7 Ma (from a Triassic sample to 25 ± 2 Ma (from a Carboniferous sample, are clearly younger than their depositional ages and demonstrate a total resetting of the AFT thermometer after deposition. The AFT ages vary among different tectonic belts and decrease from the No. Ten Faulted Zone (133–105 Ma in the northwest, the Central Horst Zone in the middle (108–37 Ma, to the East Buried Hill Zone in the south (51–25 Ma. Given the low magnitude of post-Triassic burial heating evidenced by low vitrinite reflectance values (Ro < 0.7%, the total resetting of the AFT system is speculated to result from the hot fluid flow along the faults. Thermal effects along the faults are well documented by younger AFT ages and unimodal single grain age distributions in the vicinity of the faults. Permian–early Triassic basaltic volcanism may be responsible for the early Triassic total annealing of those samples lacking connectivity with the fault. The above arguments are supported by thermal modeling results.

  4. Structural features and petroleum geology of the fold-thrust belt in the southern Tarim basin, China

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xinyuan; LUO Jinhai; WANG Qinghua

    2004-01-01

    The west Kunlun fold-thrust belt (WKFTB) and the Altun fold-thrust belt (AFTB) are respectively located in the southern margin of the Tarim basin, NW China. The analyses of typical structures and regional dynamics of the fold-thrust belts reveal their different structural and petroleum features and mechanisms. WKFTB differs from AFTB by abundant fault-related folds and triangles zones, and was formed by northward extrusion of the west Kunlun orogen. AFTB was affected synchronously by northward extrusion of the Altun orogen and the sinistral strike-slipping of the Altun Fault, so it is characterized by the minor scale and the monotonous structural styles. The Aqike anticline and the Aqike fault, of which the strikes are orthogonal to the strike of the fold-thrust belts, are regarded as the adjustive structures between both of the fold-thrust belts. The oil-gas pools of WKFTB develop mainly in the faulted-related anticline traps, but the oil-gas pools of AFTB develop mainly in the low fault-block and anticlines traps related with the paleo-uplifts. There are different exploration countermeasures for both of the fold-thrust belts.

  5. Remote sensing-based analysis on temporal and spatial changes about environmental elements in the northwest of Junggar basin, China

    Science.gov (United States)

    Yang, Liu; Nannan, Zhang; Wentong, Dong; Liqun, Zou; Shanghong, Huang

    2016-11-01

    This paper presents a study of revealing the environmental elements change during the process of local industrialization based on remote sensing technique in the western part of China. Spatio-temporal evolution of vegetation cover derived from NDVI and land surface water distribution was analyzed by time-series analysis of MSS and Landsat data from 1977 to 2011. Results show that remote sensing provide a way for monitoring the influence of local industrialization on regional environment elements in gobi region.

  6. Impacts of human activities and climate variability on green and blue water flows in the Heihe River Basin in Northwest China

    Science.gov (United States)

    Zang, C.; Liu, J.; Jiang, L.; Gerten, D.

    2013-07-01

    Human activities and climate factors both affect the availability of water resources and the sustainability of water management. Especially in already dry regions, water has become more and more scarce with increasing requirements from growing population, economic development and diet shifts. Although progress has been made in understanding variability of runoff, the impacts of climate variability and human activities on flows of both green water (actual evapotranspiration) and blue water (discharge accumulated in the river network) remain less well understood. We study the spatial patterns of blue and green water flows and the impacts on them of human activities and climate variability as simulated by the Soil and Water Assessment Tool (SWAT) for an inland Heihe river basin located in Northwest China. The results show that total green and blue water flow increased from 1980 to 2005, mainly as a result of climate variability (upward precipitation trends). Direct human activities did not significantly change the total green and blue water flow. However, land use change led to a transformation of 206 million m3 from green to blue water flow, while farmland irrigation expansion resulted in a transformation of 66 million m3 from blue to green water flow. The synchronous climate variability caused an increase of green water flow by 469 million m3 and an increase of blue water flow by 146 million m3 at the river basin level, while the geographical distribution showed an uneven change even with reductions of water flows in western sub-basins at midstream. The results are helpful to benchmark the water resources in the context of global change in the inland river basins in China. This study also provides a general approach to investigate the impacts of historical human activities and climate variability on green and blue water flows at the river basin level.

  7. Impacts of human activities and climate variability on green and blue water flows in the Heihe River Basin in Northwest China

    Directory of Open Access Journals (Sweden)

    C. Zang

    2013-07-01

    Full Text Available Human activities and climate factors both affect the availability of water resources and the sustainability of water management. Especially in already dry regions, water has become more and more scarce with increasing requirements from growing population, economic development and diet shifts. Although progress has been made in understanding variability of runoff, the impacts of climate variability and human activities on flows of both green water (actual evapotranspiration and blue water (discharge accumulated in the river network remain less well understood. We study the spatial patterns of blue and green water flows and the impacts on them of human activities and climate variability as simulated by the Soil and Water Assessment Tool (SWAT for an inland Heihe river basin located in Northwest China. The results show that total green and blue water flow increased from 1980 to 2005, mainly as a result of climate variability (upward precipitation trends. Direct human activities did not significantly change the total green and blue water flow. However, land use change led to a transformation of 206 million m3 from green to blue water flow, while farmland irrigation expansion resulted in a transformation of 66 million m3 from blue to green water flow. The synchronous climate variability caused an increase of green water flow by 469 million m3 and an increase of blue water flow by 146 million m3 at the river basin level, while the geographical distribution showed an uneven change even with reductions of water flows in western sub-basins at midstream. The results are helpful to benchmark the water resources in the context of global change in the inland river basins in China. This study also provides a general approach to investigate the impacts of historical human activities and climate variability on green and blue water flows at the river basin level.

  8. A 1000-year chironomid-based salinity reconstruction from varved sediments of Sugan Lake, Qaidam Basin, arid Northwest China, and its palaeoclimatic significance

    Institute of Scientific and Technical Information of China (English)

    CHEN JianHui; CHEN FaHu; ZHANG EnLou; BROOKS Stephen J; ZHOU AiFeng; ZHANG JiaWu

    2009-01-01

    A 1000-year high-resolution (~10 years) chironomid record from varved sediments of Sugan Lake, Qaidam Basin on the northern Tibetan Plateau, is presented. The chironomid assemblages are mainly composed of the relatively high-saline-water taxa Psectrocladius barbimanus-type and Orthocladius/Cricotopus, and the relatively low-saline-water taxa Procladius and Psectrocladius sordidellus-type. Variations in the chironomid fauna and inferred salinities suggest that over the last millennium, the Sugan Lake catchment has alternated between contrasting climatic conditions, having a dry climate during the period 990-1550 AD, a relatively humid climate during the Little Ice Age (LIA) (1550-1840 AD), and a dry climate again from 1840 AD onwards. At the decadal to centennial scale, a wet event around 1200-1230 AD, interrupting the generally arid period (990-1550 AD), and a dry event around 1590-1700 AD, punctuating the generally humid period (1550-1840 AD), are clearly documented. Trends in the chironomid-based salinity time series indicate a highly unstable climate during the LIA when salinity fluctuations were of greater magnitude and higher frequency. The effective moisture evolution in the Sugan Lake catchment during the last millennium reconstructed by chironomid analysis is in broad agreement with previous palaeo-moisture data derived from other sites in arid Northwest China (ANC). The LIA, characterized by generally humid conditions over the west-erly-dominated ANC was distinctly different from that in monsoonal China, implying an "out-of-phase" relationship between moisture evolution in these two regions during the past 1000 years.

  9. [Pollution and Potential Ecology Risk Evaluation of Heavy Metals in River Water, Top Sediments on Bed and Soils Along Banks of Bortala River, Northwest China].

    Science.gov (United States)

    Zhang, Zhao-yong; Abuduwaili, Jilili; Jiang, Feng-qing

    2015-07-01

    This paper focuses on the sources, pollution status and potential ecology risks of heavy metals (Cr, Cu, Hg, As, Cd, Pb, and Zn) in the surface water, top sediment of river bed and soil along banks of Bortala River, which locates in the oasis region of Xinjiang, northwest China. Results showed that: (1) As a whole, contents of 7 tested heavy metals of Bortala River were low, while the maximum values of Hg, Cd, Pb, and Cr in the river water were significantly higher than those of Secondary Category of the Surface Water Quality Standards of People's Republic of China (GB 3838-2002) and Drinking Water Guideline from WHO. Analysis showed that the heavy metals contents of top sediment on river bed and soils along river banks were significantly higher than those of the river water. (Correlation analysis and enrichment factor (EF) calculation showed that in the river water, top sediment on river bed and soils along river banks, Hg, Cd, Pb, and Cr mainly originated from industrial emissions, urban and rural anthropogenic activities, transportation and agricultural production activities; While Cu, Zn, and As mainly originated from natural geological background and soil parent materials. (3) Pollution assessment showed that in three matrices, the single factor pollution index(Pi) and the integrated pollution index (Pz) of 7 heavy metals were all lower than 1, and they all belonged to safe and clean levels. (4) Potential ecology risk evaluation showed that as a whole the single factor potential ecological risk (Eir) and the integrated potential ecology risks (RI) of 7 heavy metals were relatively low, and would not cause threats to the health of water and soil environment of river basin, while the potential ecology risks of Cd, Hg, Pb, and Cr were significantly higher than those of other heavy metals.

  10. [Changes in vegetation and soil characteristics under tourism disturbance in lakeside wetland of northwest Yunnan Plateau, Southwest China].

    Science.gov (United States)

    Tang, Ming-Yan; Yang, Yong-Xing

    2014-05-01

    The characteristics of vegetation and soil were investigated in Bita Lake and Shudu Lake wetlands in northwest Yunnan Plateau under tourism disturbance. The 22 typical plots in the wetlands were classified into 4 types by TWINSPAN, including primary wetland, light degradation, moderate degradation, and severe degradation. Along the degradation gradient, the plant community density, coverage, species number and Shannon diversity index increased and the plant height decreased in Bita Lake and Shudu Lake wetlands, and Whittaker diversity index increased in Bita Lake wetland. Plant species number, soil organic matter, total nitrogen, porosity, available nitrogen, available phosphorus and available potassium contents were higher in Shudu Lake wetland than in Bita Lake wetland, but the plant density, height, soil total potassium and pH were opposite. Canonical correspondence analysis (CCA) by importance values of 42 plants and 11 soil variables showed that soil organic matter, total nitrogen and total potassium were the key factors on plant species distribution in Bita Lake and Shudu Lake wetlands under tourism disturbance. TWINSPAN classification and analysis of vegetation-soil characteristics indicated the effects of tourism disturbance in Bita Lake wetland were larger than in Shudu Lake wetland.

  11. Migration, filling history and geochemical characteristics of Ordovician natural gases in the Tahe Oilfield, Tarim Basin, Northwest China

    Institute of Scientific and Technical Information of China (English)

    WANG Jie; LIU Wenhui; QIN Jianzhong; LIU Keyu; GU Yi

    2009-01-01

    Ordovician natural gases in the Tahe Oilfield are composed predominantly of hydrocarbon gases dominated by methane with a significant amount of heavy hydrocarbon gas component. The non-hydrocarbon gases include N2, CO2 and minor H2S. The Ordovician natural gases are believed to have originated from the same source rocks, and are composite of gases differing in thermal maturity. Carbon dioxide was derived from thermal metamorphism of Ordovician carbonate rocks. The generation of natural gases involves multiple stages from mature normal oil and condensate-associated gas to thermally cracked gas at the maturity to over-maturity stages. In the main part of the Tahe Oilfield, the Ordovician natural gases appear to be filled in two major phases with a typical petroleum-associated gas from southeast to northwest and from east to west in the early stage; and a thermally cracked gas from east to west in the late stage. At the same time, the oil/gas filling boundary has been primarily established between the two stages.

  12. A model for simulating the response of runoff from the mountainous watersheds of inland river basins in the arid area of northwest China to climatic changes

    Institute of Scientific and Technical Information of China (English)

    康尔泗; 程国栋; 蓝永超; 金会军

    1999-01-01

    A model for simulating the response of monthly runoff from the mountainous watersheds to climatic changes is developed.The model is based on the modifications to the HBV runoff model, and therefore represents the characteristics and runoff generation processes of inland river basins in the arid area of northwest China. Taking the mountainous watershed of an inland river, the Heihe River originating from the Qilian Mountains and running through the Hexi Corridor as an example, the monthly runoff changes under different climate scenarios are simulated. The simulation indicates that, during the years from 1994 to 2030, if the annual mean air temperature increases by 0.5℃, and precipitation keeps unchanged, then the runoff of May and October will increase because of the increase of the snow melt runoff, but the runoff of July and August will decrease to some extent because of the increase of evaporation, and as a result, the annual runoff will decrease by 4%. If the precipitation still keeps unchanged, an

  13. Coupled effects of straw and nitrogen management on N2O and CH4 emissions of rainfed agriculture in Northwest China

    Science.gov (United States)

    Htun, Yin Min; Tong, Yanan; Gao, Pengcheng; Xiaotang, Ju

    2017-05-01

    Straw incorporation is a common agricultural practice, but the additional carbon source may increase greenhouse gas emissions by stimulating microbial activity in soil, particularly when straw is applied at the same time as nitrogen (N) fertilizer. We investigated the coupled effects of straw and N fertilizer on greenhouse gas emissions in a rainfed winter wheat-summer fallow system in Northwest China. Simultaneous applications of straw and N fertilizer increased N2O emissions by up to 88%, net greenhouse gas (NGHG) emission and net greenhouse gas intensity (NGHGI) by over 90%, and the N2O emission factor by over 2-fold. When straw was applied before N fertilizer, the emission factor (0.22%) decreased by approximately one-half compared with that for simultaneous applications (0.45%). In addition, early straw incorporation decreased N2O emissions, NGHG, and NGHGI by 35% (0.62 kg N2O-N ha-1 yr-1), 40% (242 kg CO2-eq ha-1 yr-1), and 38% (42 kg CO2-eq t-1 grain), respectively. We identified the period 30-35 days after N fertilization as a crucial period for evaluating the effectiveness of management practices on N2O emissions. The time between straw and fertilizer applications was negatively related to N2O emission (R2 = 0.8031; p early straw incorporation can effectively mitigate greenhouse gas emissions by reducing N2O flux and increasing soil CH4 uptake without significantly decreasing grain yield.

  14. Scenario-Based Impact Assessment of Land Use/Cover and Climate Changes on Watershed Hydrology in Heihe River Basin of Northwest China

    Directory of Open Access Journals (Sweden)

    Feng Wu

    2015-01-01

    Full Text Available This study evaluated hydrological impacts of potential climate and land use changes in Heihe River Basin of Northwest China. The future climate data for the simulation with Soil and Water Assessment Tool (SWAT were prepared using a dynamical downscaling method. The future land uses were simulated with the Dynamic Land Use System (DLS model by establishing Multinomial Logistic Regression (MNL model for six land use types. In 2006–2030, land uses in the basin will experience a significant change with a prominent increase in urban areas, a moderate increase in grassland, and a great decrease in unused land. Besides, the simulation results showed that in comparison to those during 1981–2005 the temperature and precipitation during 2006–2030 will change by +0.8°C and +10.8%, respectively. The land use change and climate change will jointly make the water yield change by +8.5%, while they will separately make the water yield change by −1.8% and +9.8%, respectively. The predicted large increase in future precipitation and the corresponding decrease in unused land will have substantial impacts on the watershed hydrology, especially on the surface runoff and streamflow. Therefore, to mitigate negative hydrological impacts and utilize positive impacts, both land use and climate changes should be considered in water resource planning for the Heihe River Basin.

  15. 西北电网数字仿真实验室的建设%Construction of the Simulation Laboratory in Northwest China Grid

    Institute of Scientific and Technical Information of China (English)

    李刚; 张星; 林卫星; 孙海顺; 尚勇; 施荣

    2012-01-01

    A digital simulation laboratory of sending-end power grid with multi-type power sources was constructed by Northwest China Grid Company in 2009 to enhance its capability of power grid simulation and to deal with the grave technical issues including large-scale wind power integration,high-capacity DC multiple-point sending,FACTS technology application and very large-scale synchronous power gird stability.This paper introduces the configurations,functions,and main performance index of the laboratory as well as some of the major simulation works based on the laboratory.Finally,the development prospect of laboratory is discussed.%为提升电网仿真计算能力,解决大型风电并网、大容量直流多点外送、柔性交流输电技术应用及超大规模同步电网稳定等重大技术问题,西北电网公司于2009年建成"多类电源送端电网数字仿真实验室"。介绍了实验室的配置、功能、主要性能指标以及基于该实验室的若干重大仿真试验研究工作。最后展望了实验室的发展前景。

  16. Distribution and Source of Polycyclic Aromatic Hydrocarbons (PAHs) in Water Dissolved Phase, Suspended Particulate Matter and Sediment from Weihe River in Northwest China.

    Science.gov (United States)

    Chen, Yuyun; Jia, Rui; Yang, Shengke

    2015-11-06

    Weihe River is a typical river located in the arid and semi-arid regions of Northwest China. In this study, the distribution and sources of 16 polycyclic aromatic hydrocarbons (PAHs) in Weihe River were investigated. The concentrations of ∑PAHs ranged from 351 to 4427 ng/L with a mean value of 835.4 ng/L in water dissolved phase (WDP), from 3557 ng/L to 147,907 ng/L with a mean value of 20,780 ng /L in suspended particulate matter (SPM), and from 362 to 15,667 ng/g dry weight (dw) with a mean value of 2000 ng/g dw in sediment, respectively. The concentrations of PAHs in Weihe River were higher compared with other rivers in the world. In both WDP and sediment, the highest concentrations of ∑PAHs were observed in the middle reach, while the lowest concentrations of ∑PAHs were found in the lower reach. For SPM, however, the PAHs concentrations in the lower reach were highest and the PAHs concentrations in the upper reach were lowest. The ratios of anthracene/(anthracene + phenanthrene) and fluoranthene/ (fluoranthene + pyrene) reflected a pattern of both pyrolytic and petrogenic input of PAHs in Weihe River. The potential ecosystem risk assessment indicated that harmful biological impairments occur frequently in Weihe River.

  17. Variations in Stable Carbon Isotope Composition and Leaf Traits of Picea schrenkiana var. tianschanica along an Altitude Gradient in Tianshan Mountains, Northwest China

    Directory of Open Access Journals (Sweden)

    Huiwen Zhang

    2014-01-01

    Full Text Available To understand the morphological and physiological responses of leaves to changes in altitudinal gradients, we examined ten morphological and physiological characteristics in one-year-old needles of Picea schrenkiana var. tianschanica at ten points along an altitudinal gradient from 1420 to 2300 m a.s.l. on the northern slopes of the Tianshan Mountains in northwest China. Our results indicated that LA, SD, LPC, and LKC increased linearly with increasing elevation, whereas leaf δ13C, LNC, Chla + b, LDMC, LMA, and Narea varied nonlinearly with changes in altitude. With elevation below 2100 m, LNC, Narea, and Chla + b increased, while LDMC and LMA decreased with increasing altitude. When altitude was above 2100 m, these properties showed the opposite patterns. Leaf δ13C was positively correlated with Narea and LNC and negatively correlated with SD and LA, suggesting that leaf δ13C was indirectly controlled by physiological and morphological adjustments along altitudinal gradients. Based on the observed maximum values in LNC, Narea, Chla + b, and LA and the minimum values in LMA and LDMC at the elevation of 2100 m, suggesting higher photosynthetic capacity and greater potential for fast growth under superior optimum zone, we concluded that the best growing elevation for P. schrenkiana var. tianschanica in the Tianshan Mountains was approximately 2100 m.

  18. Bioaccumulation and translocation of cadmium in cole (Brassica campestris L.) and celery (Apium graveolens) grown in the polluted oasis soil,Northwest of China

    Institute of Scientific and Technical Information of China (English)

    Yiming Yang; Zhongren Nan; Zhuanjun Zhao; Zhaowei Wang; Shengli Wang; Xia Wang; Wangqiang Jin; Cuicui Zhao

    2011-01-01

    A pot experiment was conducted to study the bioaccumulation and translocation of cadmium (Cd) in cole (Brassica campestris L.) and celery (Apium graveolens) grown in the Cd-polluted oasis soil,Northwest of China.The results showed that Cd in the unpolluted oasis soil was mainly bound to carbonate fraction (F2) and Fe-Mn oxide fraction (F3).However,marked change of Cd fractions was observed with increasing soil Cd concentrations,in which the concentration of Cd in F1 (exchangeable fraction),F2 and F3 increased significantly (p < 0.001 for F1,F2 and F3).The growth of cole and celery could be facilitated by low concentrations of Cd,but inhibited by high concentrations.The correlation analysis between the fraction distribution coefficient of Cd in the soil and Cd concentration accumulated in the two vegetables showed that Cd in FI in the soil made the greatest contribution on the accumulation of Cd in the two vegetables.The high bio-concentration factor and the translocation factor of Cd in both cole and celery were observed,and Cd had higher accumulation in the edible parts of the two vegetables.Therefore,both cole and celery grown in Cd-polluted oasis soil have higher risk to human health.And the two vegetables are not suitable to be cultivated as vegetables consumed by human in the Cd-polluted oasis soil.

  19. Distinguishing between anthropogenic and climatic impacts on lake size: a modeling approach using data from Ebinur Lake in arid northwest China

    Directory of Open Access Journals (Sweden)

    Long Ma

    2014-03-01

    Full Text Available Evaluation of anthropogenic and climatic impacts on lake size variation is important for maintaining ecosystem integrity and sustaining societal development. We assumed that climate and human activity are the only drivers of lake-size variation and are independent of each other. We then evaluated anthropogenic and climatic effects on hydrological processes, using a multivariate linear model. Macro-economic data were used to describe the anthropogenic impact on lake surface area in our approach. Ebinur Lake is a shallow, closed, saline lake in arid northwest China; it has shrunk at a rapid rate over the past half century. Using our new method, we explored temporal trends of anthropogenic and climatic impacts on the lake over the past 50 years. Assessment indices indicate that the model represents observed data quite well. Compared with the reference period of 1955-1960, impacts of climate change across the catchment were generally positive with respect to lake area, except for the period from 1961 to 1970. Human activity was responsible for a reduction in lake surface area of 286.8 km2 over the last 50 years. Our approach, which uses economic variables to describe the anthropogenic impact on lake surface area, enables us to explain the lake responses to climate change and human activities quantitatively.

  20. Exploring Northwest China's agricultural water-saving strategy: analysis of water use efficiency based on an SE-DEA model conducted in Xi'an, Shaanxi Province.

    Science.gov (United States)

    Mu, L; Fang, L; Wang, H; Chen, L; Yang, Y; Qu, X J; Wang, C Y; Yuan, Y; Wang, S B; Wang, Y N

    2016-01-01

    Worldwide, water scarcity threatens delivery of water to urban centers. Increasing water use efficiency (WUE) is often recommended to reduce water demand, especially in water-scarce areas. In this paper, agricultural water use efficiency (AWUE) is examined using the super-efficient data envelopment analysis (DEA) approach in Xi'an in Northwest China at a temporal and spatial level. The grey systems analysis technique was then adopted to identify the factors that influenced the efficiency differentials under the shortage of water resources. From the perspective of temporal scales, the AWUE increased year by year during 2004-2012, and the highest (2.05) was obtained in 2009. Additionally, the AWUE was the best in the urban area at the spatial scale. Moreover, the key influencing factors of the AWUE are the financial situations and agricultural water-saving technology. Finally, we identified several knowledge gaps and proposed water-saving strategies for increasing AWUE and reducing its water demand by: (1) improving irrigation practices (timing and amounts) based on compatible water-saving techniques; (2) maximizing regional WUE by managing water resources and allocation at regional scales as well as enhancing coordination among Chinese water governance institutes.

  1. The impact of the winter North Atlantic Oscillation on the frequency of spring dust storms over Tarim Basin in northwest China in the past half-century

    Science.gov (United States)

    Zhao, Yong; Huang, Anning; Zhu, Xinsheng; Zhou, Yang; Huang, Ying

    2013-06-01

    The relationship between the frequency of spring dust storms over Tarim Basin in northwest China and the winter North Atlantic Oscillation (NAO) is investigated by using the observed dust storm frequency (DSF) and the 10 m wind velocity at 36 stations in Tarim Basin and the National Centers for Environment Prediction/National Center for Atmospheric Research reanalysis data for the period 1961-2007. The spring DSF (winter NAO) index shows a clear decreasing (increasing) linear trend over 1961-2007. The winter NAO correlates well with the subsequent spring DSF over Tarim Basin on both interannual and interdecadal time scales and its interannual to interdecadal variation plays an important role in the spring DSF. Two possible physical mechanisms are identified. One is related to the large scale anomalous circulations in spring in the middle to high troposphere modulated by the winter NAO, providing the background of dynamical conditions for the dust storm occurrences. The other is related to the shifts in the local horizontal sea level pressure (SLP) gradients and 10 m wind speed, corresponding to changes in the large scale circulations in spring. The decrease in the local 10 m wind speed due to the reduced horizontal SLP gradients over Tarim Basin during the strong winter NAO years contributes to the decline of the DSF in the subsequent spring.

  2. Modeling daily reference ET in the karst area of northwest Guangxi (China) using gene expression programming (GEP) and artificial neural network (ANN)

    Science.gov (United States)

    Wang, Sheng; Fu, Zhi-yong; Chen, Hong-song; Nie, Yun-peng; Wang, Ke-lin

    2016-11-01

    Nonlinear complexity is a characteristic of hydrologic processes. Using fewer model parameters is recommended to reduce error. This study investigates, and compares, the ability of gene expression programming (GEP) and artificial neural network (ANN) techniques in modeling ET0 by using fewer meteorological parameters in the karst area of northwest Guangxi province, China. Over a 5-year period (2008-2012), meteorological data consisting of maximum and minimum air temperature, relative humidity, wind speed, and sunshine duration were collected from four weather stations: BaiSe, DuAn, HeChi, and RongAn. The ET0 calculated by the FAO-56 PM equation was used as a reference to evaluate results for GEP, ANN, and Hargreaves models. The coefficient of determination ( R 2) and the root mean square error (RMSE) were used as statistical indicators. Evaluations revealed that GEP, and ANN, can be used to successfully model ET0. In most cases, when using the same input variables, ANN models were superior to GEP. We then established ET0 equations with fewer parameters under various conditions. GEP can produce simple explicit mathematical formulations which are easier to use than the ANN models.

  3. Chemical fractionations and bioavailability of cadmium and zinc to cole (Brassica campestris L.) grown in the multi-metals contaminated oasis soil, northwest of China

    Institute of Scientific and Technical Information of China (English)

    Yiming Yang; Zhongren Nan; Zhuanjun Zhao; Shengli Wang; Zhaowei Wang; Xia Wang

    2011-01-01

    A pot experiment was conducted to study the relationship between distribution of cadmium (Cd) and zinc (Zn) and their availability.to cole (Brassica canpestris L.) grown in the multi-metal contaminated oasis soil in northwest of China. The results showed that Cd and Zn in the unpolluted oasis soil was mainly found in the residual fractionation, however, with increasing contents of Cd and Zn in the oasis soil, the distribution of Cd and Zn changed significantly. The growth of cole could be promoted by low Cd and Zn concentration,but significantly restrained by high concentrations. There was antagonistic effect among Cd and Zn in the multi-metals contaminated oasis soil. Stepwise regression analysis between fractionations distribution coefficients of the two meals in the soil and their contents in cole showed that both Cd and Zn in the exchangeable fractionation in the oasis soil made the most contribution on the uptake of Cd and Zn in cole. The bio-concentration factor (BCF) of Cd was greater than Zn in cole, and BCFs of the two metals in leaves were greater than those in roots. The translocation factors of the two metals in cole were greater than 1, and the two metals mainly accumulated in the edible parts in cole. Therefore, cole is not a suitable vegetable for the oasis soil because of the plants notable contamination by heavy metals.

  4. Sources identification and pollution evaluation of heavy metals in the surface sediments of Bortala River, Northwest China.

    Science.gov (United States)

    Zhang, Zhaoyong; Juying, Li; Mamat, Zulpiya; QingFu, Ye

    2016-04-01

    The current study focused on the Bortala River - a typical inland river located in an oasis of arid area in northwestern China. The sediment and soil samples were collected from the river and drainage basin. Results showed that: (1) the particle size of the sand fraction of the sediments was 78-697 µm, accounting for 78.82% of the total samples; the average concentrations of eight heavy metals fell within the concentration ranges recommended by the Secondary National Standard of China, while the maximum concentrations of Pb, Cd, and Hg exceeded these standards; (2) results from multivariate statistical analysis indicated that Cu, Ni, As, and Zn originated primarily from natural geological background, while Cd, Pb, Hg and Cr in the sediments originated from human activities; (3) results of the enrichment factor analysis and the geo-accumulation index evaluation showed that Cd, Hg, and Pb were present in the surface sediments of the river at low or partial serious pollution levels, while Zn, Cr, As, Ni, and Cu existed at zero or low pollution levels; (4) calculation of the potential ecological hazards index showed that among the eight tested heavy metals, Cd, Pb, Hg, and Cr were the main potential ecological risk factors, with relative contributions of 25.43%, 22.23%, 21.16%, and 14.87%, respectively; (5) the spatial distribution of the enrichment factors (EF(S)), the Geo-accumulation index (I(geo)), and the potential ecological risk coefficient (E(r)(i)) for eight heavy metals showed that there was a greater accumulation of heavy metals Pb, Cd, and Hg in the sediments of the central and eastern parts of the river. Results of this research can be a reference for the heavy metals pollution prevention, the harmony development of the ecology protection and the economy development of the oases of inland river basin of arid regions of China, Central Asia and also other parts of the world.

  5. The Wasteland Auction Policy in Northwest China: Solving Environmental Degradation and Rural Poverty? / Rural Development in Transitional China: A Special Issue

    NARCIS (Netherlands)

    Ho, P.P.S.

    2003-01-01

    In order to relieve rural poverty and solve the problem of soil and water erosion on marginal land, various provinces and regions throughout China proclaimed a new policy in the late 1980s and early 1990s. This 'Four Wastelands Auction Policy' attempts to boost the development of land of low economi

  6. Interdisciplinary investigation on ancient Ephedra twigs from Gumugou Cemetery (3800 B.P.) in Xinjiang region, northwest China.

    Science.gov (United States)

    Xie, Mingsi; Yang, Yimin; Wang, Binghua; Wang, Changsui

    2013-07-01

    In the dry northern temperate regions of the northern hemisphere, the genus Ephedra comprises a series of native shrub species with a cumulative application history reaching back well over 2,000 years for the treatment of asthma, cold, fever, as well as many respiratory system diseases, especially in China. There are ethnological and philological evidences of Ephedra worship and utilization in many Eurasia Steppe cultures. However, no scientifically verifiable, ancient physical proof has yet been provided for any species in this genus. This study reports the palaeobotanical finding of Ephedra twigs discovered from burials of the Gumugou archaeological site, and ancient community graveyard, dated around 3800 BP, in Lop Nor region of northwestern China. The macro-remains were first examined by scanning electron microscope (SEM) and then by gas chromatography-mass spectrometry (GC-MS) for traits of residual biomarkers under the reference of modern Ephedra samples. The GC-MS result of chemical analysis presents the existence of Ephedra-featured compounds, several of which, including benzaldehyde, tetramethyl-pyrazine, and phenmetrazine, are found in the chromatograph of both the ancient and modern sample. These results confirm that the discovered plant remains are Ephedra twigs. Although there is no direct archaeological evidence for the indication of medicinal use of this Ephedra, the unified burial deposit in which the Ephedra was discovered is a strong indication of the religious and medicinal awareness of the human inhabitants of Gumugou towards this plant.

  7. 西北涡与登陆台风相互作用个例的诊断分析%Diagnostic analysis of a case on interaction between landed typhoon and Northwest China vortex

    Institute of Scientific and Technical Information of China (English)

    武麦凤; 曹玲玲; 马耀荣; 吉庆; 吴阳军

    2015-01-01

    Based on conventional surface and upper data and NCEP/NCAR 6-hourly reanalysis with 1° × 1° resolution, taking a regional rainstorm event which occurred in eastern Shaanxi, eastern Gansu and the junction of southern Shaanxi and Sichuan on 23 July 2010 as an ex-ample, we make a diagnostic analysis of the interaction between a remote landed typhoon and Northwest China vortex and its influence on the development of Northwest China vortex and rainstorms. The results indicate that (1) the interaction between remote landed typhoon and North-west China vortex changes the baroclinic, temperature-humidity and momentum structure of Northwest China vortex, and strengthens convec-tive instability and dynamic uplift effect near the Northwest China vortex. (2) The improvement of center intensity of Northwest China vortex and the ambient field in its surrounding areas has a positive feedback on the originating and strengthening of rainstorm. Namely, it extends the water-vapor transportation established by typhoon and subtropical high over the West Pacific, and strengths the dynamic uplift in the low-lev-el over rainstorm area, which results in increasing the area and intensity of rainstorm. (3) While the interaction between remote landed ty-phoon and Northwest China vortex occurs, the low level jet is established, which have a certain indicative significance to the position and in-tensity of the broad-scale but short-term severe precipitation.%利用常规高空、地面观测资料以及每日4次的1°×1° NCEP/NCAR再分析全球格点资料,以2010年7月23日发生在陕西、甘肃东部以及陕西南部与四川交界地区一次区域性大暴雨过程为例,对远距离台风与西北涡相互作用对西北涡发展和暴雨发生的影响及其原因进行了诊断分析.结果表明:(1)远距离台风和西北涡相互作用,改变了西北涡的斜压结构、温湿结构和动量结构,也增强了西北涡附近对流不稳定程度和动力抬升作用;(2)

  8. Petrogenesis and tectonic implications of Early Cretaceous S- and A-type granites in the northwest of the Gan-Hang rift, SE China

    Science.gov (United States)

    Jiang, Yao-Hui; Zhao, Peng; Zhou, Qing; Liao, Shi-Yong; Jin, Guo-Dong

    2011-01-01

    The Gan-Hang rift, trending at least 450 km in a NE-SW direction, is a part of a Mesozoic Basin and Range Province in southeastern China. Detailed SHRIMP zircon U-Pb chronology, major and trace element, and Sr-Nd-Hf isotope data of three granitic plutons and a diabasic dike in the northwest of the Gan-Hang rift, are used to explore the origin of these granites and their relationship to the evolution of the Gan-Hang rift. SHRIMP zircon U-Pb dating shows that the granitic plutons and diabasic dike were emplaced in the Early Cretaceous (122-129 Ma). The Tongshan and Damaoshan plutons, close to the Gan-Hang rift, consist mainly of weakly peraluminous granitic rocks, which show A2 subtype affinity. These granites have initial 87Sr/86Sr ratios of 0.7080-0.7103, εNd (T) values of-1.4 to-5.6 and εHf (T) (in-situ zircon) values of - 3.8 to + 1.2. Detailed elemental and isotopic data suggest that they were formed by partial melting of granulitized Mesoproterozoic metamorphic basement (including metasedimentary and metaigneous rocks) in the shallow (residual phase. The association of Early Cretaceous (122-129 Ma) S- and A-type granites in the northwest of the Gan-Hang rift marks the onset of back-arc extension or intra-arc rift. With ongoing extension the crust and lithospheric mantle became progressively thinned. The upwelling of asthenosphere triggered partial melting of both metasedimentary and metaigneous rocks in the more thinned crust close to the Gan-Hang rift, forming the A-type granitic magmas such as Tongshan and Damaoshan, whereas partial melting of metasedimentary rocks in the less thinned crust farther from the Gan-Hang rift formed the S-type granitic magmas such as Ehu. The red sediments with the total thickness more than 10,000 m have been successively deposited in the Gan-Hang rift valley since the late Early Cretaceous (~ 105 Ma), suggesting that this region experienced the most back-arc extension.

  9. The Prospects of new energy vehicle development in Northwest China%我国西北地区新能源汽车发展前景研究

    Institute of Scientific and Technical Information of China (English)

    张耀丹

    2016-01-01

    伴随着全球经济的发展,汽车的快速普及增加了环境污染的程度,使得全球环境污染逐渐加剧,如何有效开发和利用新能源成为急需解决的问题。随着能源危机和环境问题的不断加重,新能源汽车的推广和发展势在必行。而我国新能源汽车的保有量及竞争力远不及传统汽车,因此,通过对新能源汽车性能、厂商和政府等客观因素以及消费者主观因素方面的研究,进行消费者的需求分析,给予厂商及政府以决策参考具有十分重要的意义。同时针对影响西北地区新能源汽车发展的影响因素进行研究,为新能源汽车在西北的发展提供指导参考。%With the global economic development, the rapid spread of the car increases the level of environmental pollution, so that gradually increased global environmental pollution, how to effectively develop and utilize new energy has become an urgent problem. With the constantly increasing energy crisis and environmental issues, promotion and development of new energy vehicles is imperative. In China, ownership and competitiveness of new energy vehicles, far less than conventional vehicles, therefore, the study of new energy vehicle performance, manufacturers and government and other objective factors and subjective factors of consumers, carry out analysis of consumer demand, manufacturers and administration the Government is of great significance to decision-making. At the same time carry out research on factors influencing the development of new energy vehicles Northwest for new energy vehicles to provide a reference guide in the development of the Northwest.

  10. Effects of grazing on photosynthetic features and soil respiration of rangelands in the Tianshan Mountains of Northwest China.

    Science.gov (United States)

    Liu, Hua; Zang, Runguo; Chen, Han Y H

    2016-07-25

    Rangelands play a critical role in the global carbon cycle. However, the eco-physiological mechanisms associated with the effects of grazing on leaf photosynthesis and soil respiration remain poorly understood. To examine the impacts of grazing on leaf photosynthesis and soil respiration, we measured the photosynthetic parameters of the dominant species (Trifolium repens) and the soil respiration in grazed and ungrazed rangelands in the Tianshan Mountains of China. We found that grazing reduced the daily maximum net photosynthetic rate and soil respiration rates by 35% and 15%, respectively. The photosynthetic quantum yield, dark respiratory rate, and water use efficiency of T. repens leaves were reduced in grazed plots by 33.3%, 69.2%, and 21.5%, respectively. Our results demonstrated that grazing reduced carbon assimilation while increasing soil respiration within the rangelands in the Tianshan Mountains.

  11. Effects of grazing on photosynthetic features and soil respiration of rangelands in the Tianshan Mountains of Northwest China

    Science.gov (United States)

    Liu, Hua; Zang, Runguo; Chen, Han Y. H.

    2016-07-01

    Rangelands play a critical role in the global carbon cycle. However, the eco-physiological mechanisms associated with the effects of grazing on leaf photosynthesis and soil respiration remain poorly understood. To examine the impacts of grazing on leaf photosynthesis and soil respiration, we measured the photosynthetic parameters of the dominant species (Trifolium repens) and the soil respiration in grazed and ungrazed rangelands in the Tianshan Mountains of China. We found that grazing reduced the daily maximum net photosynthetic rate and soil respiration rates by 35% and 15%, respectively. The photosynthetic quantum yield, dark respiratory rate, and water use efficiency of T. repens leaves were reduced in grazed plots by 33.3%, 69.2%, and 21.5%, respectively. Our results demonstrated that grazing reduced carbon assimilation while increasing soil respiration within the rangelands in the Tianshan Mountains.

  12. The research of three-dimensional numerical simulation of groundwater-flow: taking the Ejina Basin, Northwest China as example

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Water is a primary controlling factor for economic development and ecological environmental protection in the inland river basins of arid western China. And it is groundwater, as the most important component of total water resources, that plays a dominant role in the development of western China. In recent years, the use-ratio of surface water has been raised, the groundwater recharge rate from surface water has been reduced, and groundwater has been exploited on a large scale. This has led to the decline of ground-water levels and the degradation of eco-environments in the Heihe watershed. Therefore, the study on the change in groundwater levels in recent years, as well as simulating and predicting groundwater levels in the future, have become very significant for im-proving the ecological environment of the Heihe River Basin, to coordinate the water contradiction among upper, middle and lower reaches of Heihe River Basin and to allocate the water resources. The purpose of this study is to analyze the groundwa-ter-level variations of the Ejina region based on a large scale, to develop and evaluate a conceptual groundwater model in Ejina Basin, to establish the groundwater flow model using the experimental observation data and combining Modular Three-Dimensional Groundwater Flow Model (MODFLOW) and GIS software, to simulate the regional hydrologic regime in re-cent 10 years and compare various water-delivery scenarios from midstream, and to determine which one would be the best plan for maintaining and recovering the groundwater levels and increasing the area of Ejina oasis. Finally this paper discusses the pos-sible vegetation changes of Ejina Basin in the future.

  13. 中国西北地区与东部地区跨区域金融流实证研究%Empirical Research of inter-regional financial flaw between Northwest Inland and East Coast of China

    Institute of Scientific and Technical Information of China (English)

    王培安; 白永平; 纪发俊

    2012-01-01

    西北地区是我国不发达的地区,其经济金融发展状况远远落后于东部发达地区。运用相对量分析法分析了西北地区金融流流向东部地区的现实情况,借助计量经济学协整分析VEC模型和格兰杰因果检验等方法对两地区经济差距和金融差距之间的关系进行实证研究,结果表明:东西部经济差距与金融差距存在因果关系,两地经济差距引起金融要素从落后的西北地区流向了发达的东部地区,这进一步阻碍了西北地区的经济增长,并使得两地区经济差距逐渐拉大,最后给出相应的政策建议。%For a country,capital is often transferred from the less developed regions to developed regions;this would make the more developed regions be developed and underdeveloped regions even further behind due to the lack of effective financial support.The Northwest is one of the most undeveloped regions,whose economic and financial situation have been lagged far behind the developed east part of China.From recent economic development situation,the Northwest is China's sparsely populated region with harsh natural conditions,low social productivity and not well-developed financial situation.This issue should get our government and economists to attach great importance to the related research because the uneven development of the region and the country will affect social stability.The paper uses relative quantitative analysis to study the reality of the financial flows from the Northwest to the East of China.And based on Cointegretion analysis,Granger causality test and model VEC,the author finds out that these is a stable causal relationship between the economy gap and financial gap of two regions.And the financial elements escape out of the Northwest to the East,which has hampered the economic development of the Northwest and enlarged this gap.The test results show that there are a economic gap between the East and the West and a clear financial gap

  14. Post-treatment follow-up study of abdominal cystic echinococcosis in tibetan communities of northwest Sichuan Province, China.

    Directory of Open Access Journals (Sweden)

    Tiaoying Li

    2011-10-01

    Full Text Available BACKGROUND: Human cystic echinococcosis (CE, caused by the larval stage of Echinococcus granulosus, with the liver as the most frequently affected organ, is known to be highly endemic in Tibetan communities of northwest Sichuan Province. Antiparasitic treatment with albendazole remains the primary choice for the great majority of patients in this resource-poor remote area, though surgery is the most common approach for CE therapy that has the potential to remove cysts and lead to complete cure. The current prospective study aimed to assess the effectiveness of community based use of cyclic albendazole treatment in Tibetan CE cases, and concurrently monitor the changes of serum specific antibody levels during treatment. METHODOLOGY/PRINCIPAL FINDINGS: Ultrasonography was applied for diagnosis and follow-up of CE cases after cyclic albendazole treatment in Tibetan communities of Sichuan Province during 2006 to 2008, and serum specific IgG antibody levels against Echinococcus granulosus recombinant antigen B in ELISA was concurrently monitored in these cases. A total of 196 CE cases were identified by ultrasound, of which 37 (18.9% showed evidence of spontaneous healing/involution of hepatic cyst(s with CE4 or CE5 presentations. Of 49 enrolled CE cases for treatment follow-up, 32.7% (16 were considered to be cured based on B-ultrasound after 6 months to 30 months regular albendazole treatment, 49.0% (24 were improved, 14.3% (7 remained unchanged, and 4.1% (2 became aggravated. In general, patients with CE2 type cysts (daughter cysts present needed a longer treatment course for cure (26.4 months, compared to cases with CE1 (univesicular cysts (20.4 months or CE3 type (detached cyst membrane or partial degeneration of daughter cysts (9 months. In addition, the curative duration was longer in patients with large (>10 cm cysts (22.3 months, compared to cases with medium (5-10 cm cysts (17.3 months or patients with small (<5 cm cysts (6 months. At

  15. Identification of hydrothermal alteration zones of the Baogutu porphyry copper deposits in northwest China using ASTER data

    Science.gov (United States)

    Zhang, Nannan; Zhou, Kefa

    2017-01-01

    Remote sensing technology plays a vital role in the initial stages of ore deposits exploration, with special significance in arid and semiarid regions. Advanced spaceborne thermal emission and reflection radiometer (ASTER) creates opportunities for geologists and many researchers to study the extraction of hydrothermal alterations of the porphyry copper and epithermal gold deposits. ASTER data were used to map distribution of hydrothermal alteration of deposits in the Baogutu region which is located in western Junggar, Xinjiang, China, including Baogutu II and Baogutu V deposits. Band ratio logical operator (BRLO), principal component analysis (PCA), mixture-tuned matched-filtering (MTMF), and constrained energy minimization (CEM) techniques were used for detailed hydrothermal alteration mapping. The alteration zones were identified using BRLO and PCA. The minerals subject to alteration were extracted by MTMF and CEM. The results were validated through field observation, spectral measurements, and petrographic studies. By comparing the extraction results and accuracy rates of four methods, CEM boasts the highest accuracy and identifies the altered minerals corresponding to three types of alterations at accuracy of over 80%. The identifying result of CEM method indicates that the prospect areas that were located in the southeast part of the Baogutu II rocks and in the southwest part of the Baogutu V rocks are valuable for further exploration.

  16. Identification and Evolution of Groundwater Chemistry in the Ejin Sub-Basin of the Heihe River, Northwest China

    Institute of Scientific and Technical Information of China (English)

    SU Yong-Hong; FENG Qi; ZHU Gao-Feng; SI Jian-Hua; ZHANG Yan-Wu

    2007-01-01

    Hydro-chemical characteristics of groundwater and their changes as affected by human activities were studied in the Ejin Sub-Basin of the Inner Mongolia Autonomous Region, China, to understand the groundwater evolution, to identify the predominant geochemical processes taking place along the horizontal groundwater flow path, and to characterize anthropogenic factors affecting the groundwater environment based on previous data. The concentrations of major ions and total dissolved solids (TDS) in the groundwater showed a great variation, with 62.5% of the samples being brackish (TDS ≥ 1000 mg L-1). The groundwater system showed a gradual hydro-chemical zonation composed of Na+-HCO-3, Na+-Mg2+-SO2-4Cl-, and Na+-Cl-. The relationships among the dissolved species allowed identification of the origin of solutes and the processes that generated the observed water compositions. The dissolution of halite, dolomite, and gypsum explained, in part, the presence of Na+, K+, Cl-, SO2-4, and Ca2+, but other processes, such as mixing, Na+ exchange for Ca2+ and Mg2+, and calcite precipitation also contributed to the composition of water. Human activity, in particular large-scale water resources development associated with dramatic population growth in the last 50 years, has led to tremendous changes in the groundwater regime, which reflected in surface water runoff change, decline of groundwater table and degeneration of surface water and groundwater quality. Solving these largely anthropogenic problems requires concerted, massive and long-term efforts.

  17. Analysis of the Ore-Controlling Structure of Ductile Shear Zone Type Gold Deposit in Southern Beishan Area, Gansu, Northwest China

    Institute of Scientific and Technical Information of China (English)

    Chen Bailin; Wu Ganguo; Ye Dejin; Liu Xiaochun; Shu Bin; Yang Nong

    2007-01-01

    The ductile shear zone-type gold deposit is a kind that both the ore-forming mechanism and ore-controlling factors are closely related to the ductile shear zone and its evolution. Ductile shear zone develops in Beishan area, Gansu of Northwest China, and develops especially well in the south belt.The controls of the ductile shear zone on gold deposits are as follows. (1) The regional distribution of gold deposits (and gold spots) is controlled by the ductile shear zone. (2) The ductile-brittle shear zone is formed in the evolution process of ductile shear zone and both are only ore-bearing structures and control the shape, attitude, scale, and distribution of mineralization zones and ore-bodies. (3) Compresso-shear ductile deformation results in that the main kind of gold mineralization is altered mylonite type and the main alteralization is metasomatic. (4) Ore-bearing fracture systems are mainly P-type ones, some D-type and R-type ones, but only individual R'-type and T-type ones. (5) Dynamic differentiation and dynamic metamorphic hydrothermal solution resulting from ductile deformation is one of the sources of ore-forming fluid of gold mineralization, and this is identical with that ore-forming materials are mainly from metamorphic rocks, and ore-forming fluid is mainly composed of metamorphic water, and with the fluid inclusion and geo-chemical characteristics of the deposit. (6) There is a negative correlation between the gold abundance and susceptibility anisotropy (P) of the altered mylonlte samples from the deposit, which shows that the gold mineralization is slightly later than the structural deformation. All above further expound the ore-forming model of the ductile shear zone type of gold deposits.

  18. Distinct groundwater recharge sources and geochemical evolution of two adjacent sub-basins in the lower Shule River Basin, northwest China

    Science.gov (United States)

    Wang, Liheng; Dong, Yanhui; Xie, Yueqing; Song, Fan; Wei, Yaqiang; Zhang, Jiangyi

    2016-08-01

    Based on analysis of groundwater hydrogeochemical and isotopic data, this study aims to identify the recharge sources and understand geochemical evolution of groundwater along the downstream section of the Shule River, northwest China, including two sub-basins. Groundwater samples from the Tashi sub-basin show markedly depleted stable isotopes compared to those in the Guazhou sub-basin. This difference suggests that groundwater in the Tashi sub-basin mainly originates from meltwater in the Qilian Mountains, while the groundwater in the Guazhou sub-basin may be recharged by seepage of the Shule River water. During the groundwater flow process in the Tashi sub-basin, minerals within the aquifer material (e.g., halite, calcite, dolomite, gypsum) dissolve in groundwater. Mineral dissolution leads to strongly linear relationships between Na+ and Cl- and between Mg2++ Ca2+ and SO4 2- + HCO3 -, with stoichiometry ratios of approximately 1:1 in both cases. The ion-exchange reaction plays a dominant role in hydrogeochemical evolution of groundwater in the Guazhou sub-basin and causes a good linear relationship between (Mg2++ Ca2+)-(SO4 2- + HCO3 -) and (Na++ K+)-Cl- with a slope of -0.89 and also results in positive chloroalkaline indices CAI 1 and CAI 2. The scientific results have implications for groundwater management in the downstream section of Shule River. As an important irrigation district in Hexi Corridor, groundwater in the Guazhou sub-basin should be used sustainably and rationally because its recharge source is not as abundant as expected. It is recommended that the surface water should be used efficiently and routinely, while groundwater exploitation should be limited as much as possible.

  19. Effects of groundwater lateral flow on land surface processes: a case study in Heihe River Basin, north-west of China

    Science.gov (United States)

    Xie, Z.; Zeng, Y.; Yu, Y.

    2015-12-01

    As an important component of hydrologic cycle, groundwater is affected by topography, vegetation, climate condition, and anthropogenic activity. Groundwater horizontal convergence and divergence and vertical interaction with soil water result in variations of soil moisture, water and energy exchanges between the land surface and the atmosphere, which ultimately influences climate. In this work, a two-dimensional groundwater lateral flow scheme based on groundwater mass equation, is developed and incorporated into the land surface model CLM4.5 to investigate effects of groundwater lateral flow on land surface processes in a river basin. A 30-year simulation with groundwater lateral flow and a control run without the horizontal movement are conducted over Heihe River Basin, north-west China, from 1979 to 2012 using the developed model. Results show that with groundwater lateral flow, equilibrium distribution of groundwater table shows more spatial variability following topography rather than the water balance between local precipitation and evapotranspiration, and are much closer to well observations especially over middle reaches area. Along with shallower groundwater table over piedmont areas in the middle reaches, increased soil moisture is shown which alleviates the underestimation of CLM4.5 at here. Changes in evapotranspiration are occurred and it is mainly controlled by the variation of local surface soil moisture, since water is the major limitation factor of evapotranspiration over this arid area. Besides, groundwater lateral flow can change the distribution of surface runoff by changing the saturated area fraction of each model grid cell. Energy cycle also responds to the changes of hydrological cycle which redistributes the sensible heat flux and latent heat flux in the entire basin.

  20. Analysis of Water Resources Supply and Demand and Security of Water Resources Development in Irrigation Regions of the Middle Reaches of the Heihe River Basin, Northwest China

    Institute of Scientific and Technical Information of China (English)

    JI Xi-bin; KANG Er-si; CHEN Ren-sheng; ZHAO Wen-zhi; XIAO Sheng-chun; JIN Bo-wen

    2006-01-01

    Based on the data for meteorology, hydrology, soil, planting, vegetation, and socio-economic development of the irrigation region in the middle reaches of the Heihe River basin, Northwest China, the model of balance of water supply and demand in the region was established, and the security of water resource was assessed, from which the results that the effects of unified management of water resources in the Heihe River basin between Gansu Province and Inner Mongolia on regional hydrology are significant with a decrease in water supply diverted from Heihe River and an increase in groundwater extracted. In addition, it was found that the groundwater level has been steadily decreasing due to over pumping and decrease in recharges. In present year (2003), the volume of potential groundwater in the irrigation districts is far small because of the groundwater overdraft; even in the particular regions, there is no availability of groundwater resources for use. By 2003, water supply is not sufficient to meet the water demand in the different irrigation districts, the sustainable development and utilization of water resources are not secured, and the water supply crisis occurs in Pingchuan irrigation district. Achieving water security for the sustainable development of society, agriculture, economy, industry, and livelihoods while maintaining or improving the abilities of the management and planning of water resources, determining of the reasonable percentage between water supply and groundwater utilization and water saving in agricultural irrigation are taken into account. If this does not occur, it is feared that the present performance of water development and planning may further aggravate the problem of scarcities of water resources and further damage the fragile ecological system.

  1. Effects of land use/land cover and climate changes on surface runoff in a semi-humid and semi-arid transition zone in northwest China

    Science.gov (United States)

    Yin, Jing; He, Fan; Jiu Xiong, Yu; Qiu, Guo Yu

    2017-01-01

    Water resources, which are considerably affected by land use/land cover (LULC) and climate changes, are a key limiting factor in highly vulnerable ecosystems in arid and semi-arid regions. The impacts of LULC and climate changes on water resources must be assessed in these areas. However, conflicting results regarding the effects of LULC and climate changes on runoff have been reported in relatively large basins, such as the Jinghe River basin (JRB), which is a typical catchment (> 45 000 km2) located in a semi-humid and arid transition zone on the central Loess Plateau, northwest China. In this study, we focused on quantifying both the combined and isolated impacts of LULC and climate changes on surface runoff. We hypothesized that under climatic warming and drying conditions, LULC changes, which are primarily caused by intensive human activities such as the Grain for Green Program, will considerably alter runoff in the JRB. The Soil and Water Assessment Tool (SWAT) was adopted to perform simulations. The simulated results indicated that although runoff increased very little between the 1970s and the 2000s due to the combined effects of LULC and climate changes, LULC and climate changes affected surface runoff differently in each decade, e.g., runoff increased with increased precipitation between the 1970s and the 1980s (precipitation contributed to 88 % of the runoff increase). Thereafter, runoff decreased and was increasingly influenced by LULC changes, which contributed to 44 % of the runoff changes between the 1980s and 1990s and 71 % of the runoff changes between the 1990s and 2000s. Our findings revealed that large-scale LULC under the Grain for Green Program has had an important effect on the hydrological cycle since the late 1990s. Additionally, the conflicting findings regarding the effects of LULC and climate changes on runoff in relatively large basins are likely caused by uncertainties in hydrological simulations.

  2. A 100-year record of climate change and human activities inferred from the geochemical composition of sediments in Chaiwopu Lake, arid northwest China

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    Wen Liu

    2016-01-01

    Full Text Available An 81-cm sediment core from Chaiwopu Lake in arid northwest China was analyzed for 137Cs activity and concentrations of major and trace elements. We used these data to discriminate between the influence of climate change and human activities on the geochemical change of the lake sediments over the past century. Elements Al, K, Ba, Ti, V, Fe, Ni, Mn, Li, and Be were mainly from detrital. Ca, Sr, and Mg concentrations were controlled by chemical weathering processes. Na came mainly from salt precipitation caused by a decline in water level. Enrichment factors for Pb and P in recent deposits are large, indicating they were influenced by human activies. Geochemical conditions during the past century can be divided into three stages: i From ca. 1900 to the1950s element concentrations varied widely and frequently. In general, concentrations of typical mobile elements Ca, Sr, and Mg stay relatively high whereas values for other elements remained relatively low. This was interpreted to reflect variable climate under conditions of weak surface erosion intensity. ii From the 1950s to the early 2000s, element concentrations display less variability. The Al, K, Ba, Ti, P, Cr, V, Fe, Ni, Mn, Co, Cu, Li, Zn, Be, Pb, and Na contents were generally higher, whereas contents of Ca, Sr, and Mg were on average lower. This indicates that the regional environment was conducive to surface erosion. Enrichment of trace metals and major elements in the sediment reflects enhanced human activities. iii In the last decade, Pb and P exhibited a great increase, possibly associated with the input from fossil fuel combustion, sewage discharge and non-point-source pollution in the watershed. The lake volume decreased substantially because of groundwater extraction for municipal water, which resulted in a marked increase in salinity and enhanced Na precipitation.

  3. A Large-scale Tertiary Salt Nappe Complex in the Leading Edge of the Kuqa Foreland Fold-Thrust Belt, the Tarim Basin, Northwest China

    Institute of Scientific and Technical Information of China (English)

    TANG Liangjie; JIN Zhijun; JIA Chengzao; PI Xuejun; CHEN Shuping; XIE Huiwen; WANG Ziyu

    2004-01-01

    The tectono-stratigraphic sequences of the Kuqa foreland fold-thrust belt in the northern Tarim basin,northwest China, can be divided into the Mesozoic sub-salt sequence, the Paleocene-Eocene salt sequence and the Oligocene-Quaternary supra-salt sequence. The salt sequence is composed mainly of light grey halite, gypsum, marl and brown clastics. A variety of salt-related structures have developed in the Kuqa foreland fold belt, in which the most fascinating structures are salt nappe complex. Based on field observation, seismic interpretation and drilling data, a large-scale salt nappe complex has been identified. It trends approximately east-west for over 200 km and occurs along the west Qiulitag Mountains. Its thrusting displacement is over 30 km. The salt nappe complex appears as an arcuate zone projecting southwestwards along the leading edge of the Kuqa foreland fold belt. The major thrust fault is developed along the Paleocene-Eocene salt beds. The allochthonous nappes comprise large north-dipping faulting monoclines which are made up of Paleocene-Pliocene sediments. Geological analysis and cross-section restoration revealed that the salt nappes were mainly formed at the late Himalayan stage (c.a. 1.64 Ma BP) and have been active until the present day. Because of inhomogeneous thrusting, a great difference may exist in thrust displacement, thrust occurrence, superimposition of allochthonous and autochthonous sequences and the development of the salt-related structures, which indicates the segmentation along the salt nappes. Regional compression, gravitational gliding and spreading controlled the formation and evolution of the salt nappe complex in the Kuqa foreland fold belt.

  4. The different influence of the residual layer on the development of the summer convective boundary layer in two deserts in northwest China

    Science.gov (United States)

    Lin, Zhao; Bo, Han; Shihua, Lv; Lijuan, Wen; Xianhong, Meng; Zhaoguo, Li

    2016-12-01

    The development of the atmospheric boundary layer is closely connected with the exchange of momentum, heat, and mass near the Earth's surface, especially for a convective boundary layer (CBL). Besides being modulated by the buoyancy flux near the Earth's surface, some studies point out that a neutrally stratified residual layer is also crucial for the appearance of a deep CBL. To verify the importance of the residual layer, the CBLs over two deserts in northwest China (Badan Jaran and Taklimakan) were investigated. The summer CBL mean depth over the Taklimakan Desert is shallower than that over the Badan Jaran Desert, even when the sensible heat flux of the former is stronger. Meanwhile, the climatological mean residual layer in the Badan Jaran Desert is much deeper and neutrally stratified in summer. Moreover, we found a significant and negative correlation between the lapse rate of the residual layer and the CBL depth over the Badan Jaran Desert. The different lapse rates of the residual layer in the two regions are partly connected with the advection heating from large-scale atmospheric circulation. The advection heating tends to reduce the temperature difference in the 700 to 500-hPa layer over the Badan Jaran Desert, and it increases the stability in the same atmospheric layer over the Taklimakan Desert. The advection due to climatological mean atmospheric circulation is more effective at modulating the lapse rate of the residual layer than from varied circulation. Also, the interannual variation of planetary boundary layer (PBL) height over two deserts was found to covary with the wave train.

  5. Effects of habitat disturbance on the pollination system of Ammopiptanthus mongolicus (Maxim) Cheng f. at the landscape-level in an arid region of Northwest China.

    Science.gov (United States)

    Chen, Min; Zhao, Xue-Yong; Zuo, Xiao-An; Mao, Wei; Qu, Hao; Zhu, Yang-Chun

    2016-05-01

    Ammopiptanthus mongolicus is an ecologically important species in the arid region of Northwest China. Habitat disturbance can significantly affect plant mating success and ultimately species viability. Pollen limitation of plant reproduction occurs in many plant species, particularly those under habitat disturbance. However, previous investigations have demonstrated differences in pollen limitation between conserved and disturbed sites. We compared the phenology, pollen limitation, pollinators and breeding system of both sites to determine whether habitat disturbance has generated changes in these plant components. We found that the species differed in four aspects. First, blooming duration and flowering peak were longer in the disturbed site than in the conserved site. Second, A. mongolicus can be pollen-limited and pollen limitation was more intense in the conserved site than in the disturbed site. Third, Anthophora uljanini was found to be a frequent pollinator in the conserved site, while Apis mellifera was the most effective and frequent flower visitor. More pollinator visits were recorded in the disturbed site, which could explain the differences in reproductive success. Finally, seed set was higher in the disturbed site than in the conserved site. We found that outcrossing was dominant in both sites and that agamospermy and self-pollination played complementary roles to ensure reproduction. Differences in flower production influenced by artificial selection and pollinator type explain the different seed set in both sites, whereas habitat disturbance cause changes differences in the pollination process and limits pollen flow. The balance between artificial management and mating success is crucial to analysis of the pollination process and manipulation of A. mongolicus population size.

  6. [Effects of different long-term fertilization patterns on Fuji apple yield, quality, and soil fertility on Weibei Dryland, Shaanxi Province of Northwest China].

    Science.gov (United States)

    Zhao, Zuo-Ping; Tong, Yan-An; Liu, Fen; Wang, Xiao-Ying

    2013-11-01

    A 7-year (2003-2010) located field experiment was conducted to evaluate the effects of different long-term fertilization patterns on the Fuji apple yield, quality, and soil fertility on the Weibei Dryland, Shaanxi Province of Northwest China. Seven treatments were installed, i. e., no fertilization (CK), inorganic P and K fertilization (PK), inorganic N and K fertilization (NK), inorganic N and P fertilization (NP), inorganic N, P, and K fertilization (NPK), swine manure (M), and half inorganic N, P, and K combined with half swine manure (NPKM). Each treatment had three replications. Fertilization increased the apple yield. The average yield in the 7 years under fertilization was increased by 14.4%-63.8%, as compared to the CK. The average yield decreased in the order of NPKM > NPK > or = M > NP > or = NK > PK > CK. In treatments NPKM, M, and NPK, the fruit sugar/acid (S:A) ratio, vitamin C, soluble solid, and hardness tended to be increased with time, with a smaller yearly fluctuation in treatments NPKM and M. In treatment NPKM, the S:A ratio and vitamin C increased by 30.9% and 17.5%, respectively after five years, as compared to the CK. Long-term rational fertilization increased the soil organic matter (SOC) content in 0-20 cm layer, with the largest increment in treatments NPKM and M (28.8% and 29.3%, respectively). The soil available N, P, and K contents in all layers in treatments NPK, NPKM, and M increased significantly, and the soil available N content in 0-20, 20-40, and 40-60 cm layers in treatment NPK was increased by 22.7%, 37.3%, and 53.4%, respectively. As compared to treatment NPK, the soil available P content in treatment NPKM was increased by 18.7%. In all fertilization treatments, the soil available Pcontent was significantly higher in upper layer than in lower layer.

  7. Spatial and seasonal variations of pesticide contamination in agricultural soils and crops sample from an intensive horticulture area of Hohhot, North-West China.

    Science.gov (United States)

    Zhang, Fujin; He, Jiang; Yao, Yiping; Hou, Dekun; Jiang, Cai; Zhang, Xinxin; Di, Caixia; Otgonbayar, Khureldavaa

    2013-08-01

    The spatial variability and temporal trend in concentrations of the organochlorine pesticides (OCPs), hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT), in soils and agricultural corps were investigated on an intensive horticulture area in Hohhot, North-West China, from 2008 to 2011. The most frequently found and abundant pesticides were the metabolites of DDT (p,p'-DDE, p,p'-DDT, o,p'-DDT and p,p'-DDD). Total DDT concentrations ranged from ND (not detectable) to 507.41 ng/g and were higher than the concentration of total HCHs measured for the range of 4.84-281.44 ng/g. There were significantly positive correlations between the ∑DDT and ∑HCH concentrations (r (2)>0.74) in soils, but no significant correlation was found between the concentrations of OCPs in soils and clay content while a relatively strong correlation was found between total OCP concentrations and total organic carbon (TOC). β-HCH was the main isomer of HCHs, and was detected in all samples; the maximum proportion of β-HCH compared to ∑HCHs (mean value 54%) was found, suggesting its persistence. The α/γ-HCH ratio was between 0.89 and 5.39, which signified the combined influence of technical HCHs and lindane. Low p,p'-DDE/p,p'-DDT in N1, N3 and N9 were found, reflecting the fresh input of DDTs, while the relatively high o,p'-DDT/p,p'-DDT ratios indicated the agricultural application of dicofol. Ratios of DDT/(DDE+DDD) in soils do not indicate recent inputs of DDT into Hohhot farmland soil environment. Seasonal variations of OCPs featured higher concentrations in autumn and lower concentrations in spring. This was likely associated with their temperature-driven re-volatilization and application of dicofol in late spring.

  8. Distinct groundwater recharge sources and geochemical evolution of two adjacent sub-basins in the lower Shule River Basin, northwest China

    Science.gov (United States)

    Wang, Liheng; Dong, Yanhui; Xie, Yueqing; Song, Fan; Wei, Yaqiang; Zhang, Jiangyi

    2016-12-01

    Based on analysis of groundwater hydrogeochemical and isotopic data, this study aims to identify the recharge sources and understand geochemical evolution of groundwater along the downstream section of the Shule River, northwest China, including two sub-basins. Groundwater samples from the Tashi sub-basin show markedly depleted stable isotopes compared to those in the Guazhou sub-basin. This difference suggests that groundwater in the Tashi sub-basin mainly originates from meltwater in the Qilian Mountains, while the groundwater in the Guazhou sub-basin may be recharged by seepage of the Shule River water. During the groundwater flow process in the Tashi sub-basin, minerals within the aquifer material (e.g., halite, calcite, dolomite, gypsum) dissolve in groundwater. Mineral dissolution leads to strongly linear relationships between Na+ and Cl- and between Mg2++ Ca2+ and SO4 2- + HCO3 -, with stoichiometry ratios of approximately 1:1 in both cases. The ion-exchange reaction plays a dominant role in hydrogeochemical evolution of groundwater in the Guazhou sub-basin and causes a good linear relationship between (Mg2++ Ca2+)-(SO4 2- + HCO3 -) and (Na++ K+)-Cl- with a slope of -0.89 and also results in positive chloroalkaline indices CAI 1 and CAI 2. The scientific results have implications for groundwater management in the downstream section of Shule River. As an important irrigation district in Hexi Corridor, groundwater in the Guazhou sub-basin should be used sustainably and rationally because its recharge source is not as abundant as expected. It is recommended that the surface water should be used efficiently and routinely, while groundwater exploitation should be limited as much as possible.

  9. [Effects of short-term fencing on organic carbon fractions and physical stability of sandy sierozem in desert steppe of Northwest China].

    Science.gov (United States)

    Yang, Xin-Guo; Song, Nai-Ping; Li, Xue-Bin; Liu, Bing-Ru

    2012-12-01

    In order to explore the change patterns of organic carbon fractions and physical stability of sandy sierozem in desert steppe at the early stage of fencing, 0-40 cm soil samples were collected from a 5-year fenced desert steppe (inside the fence) and a free grazing steppe (outside the fence) in Yanchi County of Ningxia, Northwest China, with the soil organic carbon, labile organic carbon, and particulate organic carbon contents and soil particle composition analyzed. No significant differences were observed in the soil organic carbon content and soil particle composition inside and outside the fence. The average soil organic carbon inside and outside the fences was 3.25 g x kg(-1), the percentages of sand, silt, and clay were averagely 72%, 16%, and 12%, respectively, and the soil physical stability index was 1.30% -1.31%. The soil active organic carbon showed a significant change in 10-20 cm layer. The soil labile organic carbon content was 0.80 g x kg(-1) inside the fence, which was significantly higher than that outside the fence (0.62 g x kg(-1)). The percentage of soil particulate organic carbon was 50.9% inside the fence, which was also significantly higher than that outside the fence (31.7%). The soil texture inside the fence changed from sandy to loam, and the soil labile organic carbon content increased gradually; while the soil texture outside the fence was sandy, and its vertical change was relatively smooth. The organic carbon of sandy si- erozem in the desert steppe under the conditions of short-term fencing was still in a balance between consumption and accumulation, the soil texture was relatively stable, and the soil physical stability changed little. It was suggested that the soil active organic carbon content and its relative percentage in 10-20 cm layer could be used as the indicators of early soil quality change of desert steppe.

  10. The effects of clouds and aerosols on net ecosystem CO2 exchange over semi-arid Loess Plateau of Northwest China

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    T. Wang

    2010-09-01

    Full Text Available The impacts of clouds and atmospheric aerosols on the terrestrial carbon cycle at semi-arid Loess Plateau in Northwest China are investigated, by using the observation data obtained at the SACOL (Semi-Arid Climate and Environment Observatory of Lanzhou University site. Daytime (solar elevation angles of larger than 50° net ecosystem exchange (NEE of CO2 obtained during the midgrowing season (July–August are analyzed with respect to variations in the diffuse radiation, cloud cover and aerosol optical depth (AOD. Results show a significant impact by clouds on the CO2 uptake by the grassland (with smaller LAI values located in a semi-arid region, quite different from areas covered by forests and crops. The light saturation levels in the canopy are low, with a value of about 434.8 W m−2. Thus, under overcast conditions of optically thick clouds, the CO2 uptake increases with increasing clearness index (the ratio of global solar radiation received at the Earth surface to the extraterrestrial irradiance at a plane parallel to the Earth surface, and a maximum CO2 uptake and light use efficiency of vegetation occur with the clearness index of about 0.37 and lower air temperature. Under other sky conditions, CO2 uptake decreases with cloudiness but light use efficiency is enhanced, due to increased diffuse fraction of PAR. Additionally, under cloudy conditions, changes in the NEE of CO2 also result from the interactions of many environmental factors, especially the air temperature. In contrast to its response to changes in solar radiation, the carbon uptake shows a slightly negative response to increased AOD. The reason for the difference in the response of the semi-arid grassland from that of the forest and crop lands may be due to the difference in the canopy's architectural structure.

  11. On the factors influencing surface-layer energy closure and their seasonal variability over the semi-arid Loess Plateau of Northwest China

    Directory of Open Access Journals (Sweden)

    X. Xiao

    2012-03-01

    Full Text Available The energy observed in the surface layer, when using eddy-covariance techniques to measure turbulent fluxes, is not balanced. Important progress has been made in recent years in identifying potential reasons for this lack of closure in the energy balance, but the problem is not yet resolved. In this paper, long-term data that include output of tower, radiation, surface turbulence flux and soil measurement collected from September 2006 to August 2010 in the Semi-Arid Climate Change and Environment Observatory, Lanzhou University, in the semi-arid Loess Plateau of Northwest China, were analysed, focusing on the seasonal characteristics of the surface energy and the factors that have impact on the energy balance closure (EBC. The analysis shows that (1 the long-term observations are successful; the interaction between the land and the atmosphere in semi-arid climates can be represented by the turbulent transport of energy. In addition, even though the residual is obvious, this suggests that the factors that impact the EBC are stable, and their seasonal variations are identical. The analysis also shows that (2 four factors have obvious impact on the EBC: the diverse schemes for surface soil heat flux, the flux contribution from the target source area, the low-frequency part of the turbulence spectra, and the strength of atmospheric turbulence motion. The impact of these four factors on the EBC are similar in all seasons. Lastly, the results indicate that (3 atmospheric turbulence intensity is a very important factor in terms of its impact on the EBC. The relative turbulence intensity, RIw, characterises the strength of atmospheric turbulence motion, and is found to exert a noticeable impact on the EBC; in all seasons, the EBC is increased when the relative turbulence intensity is enlarged.

  12. Assessment of spatial and temporal patterns of green and blue water flows under natural conditions in inland river basins in Northwest China

    Directory of Open Access Journals (Sweden)

    C. F. Zang

    2012-08-01

    Full Text Available In arid and semi-arid regions freshwater resources have become scarcer with increasing demands from socio-economic development and population growth. Until recently, water research and management has mainly focused on blue water but ignored green water. Furthermore, in data poor regions hydrological flows under natural conditions are poorly characterised but are a prerequisite to inform future water resources management. Here we report on spatial and temporal patterns of both blue and green water flows that can be expected under natural conditions as simulated by the Soil and Water Assessment Tool (SWAT for the Heihe river basin, the second largest inland river basin in Northwest China. Calibration and validation at two hydrological stations show good performance of the SWAT model in modelling hydrological processes. The total green and blue water flows were 22.05–25.51 billion m3 in the 2000s for the Heihe river basin. Blue water flows are larger in upstream sub-basins than in downstream sub-basins mainly due to high precipitation and a large amount of snow and melting water in upstream. Green water flows are distributed more homogeneously among different sub-basins. The green water coefficient was 87%–89% in the 2000s for the entire river basin, varying from around 80%–90% in up- and mid-stream sub-basins to above 90% in downstream sub-basins. This is much higher than reported green water coefficients in many other river basins. The spatial patterns of green water coefficients were closely linked to dominant land covers (e.g. snow cover upstream and desert downstream and climate conditions (e.g. high precipitation upstream and low precipitation downstream. There are no clear consistent historical trends of change in green and blue water flows and the green water coefficient at both the river basin and sub-basin levels. This study provides insights into green and blue water endowments under natural conditions for the entire

  13. Relationship Between the Number of Summer Typhoons Engendered over the Northwest Pacific and South China Sea and Main Climatic Conditions in the Preceding Winter and Spring

    Institute of Scientific and Technical Information of China (English)

    XIAO Ziniu; LIANG Hongli; LI Chongyin

    2010-01-01

    Based on the monthly NCEP/NCAR reanalysis data, OLR (outgoing longwave radiation) data, and tropical cyclone data from the Typhoon Annual and Tropical Cyclone Annual edited by China Meteorological Administration, the relationship between the number of tropical cyclones (with the strongest wind ≥ 17 m s-1, including tropical storm, strong tropical storm, and typhoon, simply called typhoon in this paper) engendered over the Northwest Pacific and South China Sea in summer and the associated climate conditions is studied. First, the characteristics and differences of the climatic conditions between the years with more typhoons and those with fewer typhoons are compared. The results show that the summer typhoon has a close relationship with SST (sea surface temperature) and ITCZ (intertropical convergence zone) anomalies in the preceding winter and spring. With a La Nina like SST anomaly (SSTA) pattern in the preceding winter and spring, the ITCZ will move northwestward and be enhanced around 160°E in the equatorial central Pacific from the preceding winter to spring. The activity of the Pacific ITCZ is in general stronger and its location is more northward than usual, especially in the typhoon genesis region in West Pacific. This background is propitious to have more typhoons in summer. On the other hand, an El Nino like SSTA pattern in the preceding winter will be companied with weaker ITCZ activities, and its location is more southward over the equatorial western Pacific from the preceding winter to spring; this background is propitious to have fewer typhoons in summer. In the year with more typhoons, the warm SST over West Pacific in the preceding winter provides a favorable condition for typhoon fromation in the following summer. It enhances the convergence in the troposphere and increases the water vapor supply to the warm SST region. In the following spring, the perturbation of the tropical ITCZ plays a more important role. When the ITCZ moves northward in

  14. Epidemiology of gastroesophageal reflux disease:A general population-based study in Xi'an of Northwest China

    Institute of Scientific and Technical Information of China (English)

    Jin-Hai Wang; Jin-Yan Luo; Lei Dong; Jun Gong; Ming Tong

    2004-01-01

    AIM: Gastroesophageal reflux disease (GERD) is a common disorder in the Western population, but detailed populationbased data in China are limited. The aim of this study was to understand the epidemiology of symptomatic gastroesophageal reflux (SGER) in adults of Xi′an, a northwestern city of China,and to explore the potential risk factors of GERD.METHODS: Symptoms suggestive of GERD, functional dyspepsia (FD), irritable bowel syndrome (IBS), upper respiratory diseases and some potential risk factors were investigated in a face-to-face manner in a region-stratified random samples of 2 789 residents aged 18-70 years in Xi′an by using a standardized questionnaire.METHODS: With a response rate of 91.8%, the prevalence of SGER was 16.98% (95% CI, 14.2-18.92) in Xi′an adults,and no gender-related difference was observed (P<0.05).SGER was more common among subjects aged 30-70 years than in those aged 18-29 years (P<0.01). The prevalence of SGER in rural, urban and suburban subjects was 21.07%,17.44% and 12.12%, respectively, and there was a significant difference between rural, urban and suburban regions (P<0.05). Compared with subjects without SGER,the prevalence of symptoms suggestive of FD and IBS,pneumonia, asthma, bronchitis, laryngitis, pharyngitis,chronic cough, wheeze, globus sensation, oral ulcer and snore was significantly increased in subjects with SGER (P<0.01). Heavy smoking (OR=5.76; CI, 3.70-6.67), heavy alcohol use (OR=2.85; CI, 1.67-4.49), peptic ulcer (OR=5.76;CI, 3.99-8.32), cerebral palsy (OR=3.97; CI, 1.97-8.00),abdominal operation (OR=2.69; CI, 1.75-4.13), obesity (OR=2.16; CI, 1.47-3.16), excessive food intake (OR=1.43;CI, 1.17-1.15), sweet food (OR=1.23; CI, 0.89-1.54),and consumption of coffee (OR=1.23; CI, 0.17-2.00) were independently associated with SGER. The episodes of GERD were commonly precipitated by dietary factors (66.05%),followed by body posture (26.54%), iii temper (23.72%),fatigue (22.32%) and stress (10

  15. Characterizing hydrological processes on loess slopes using electrical resistivity tomography - A case study of the Heifangtai Terrace, Northwest China

    Science.gov (United States)

    Zeng, R. Q.; Meng, X. M.; Zhang, F. Y.; Wang, S. Y.; Cui, Z. J.; Zhang, M. S.; Zhang, Y.; Chen, G.

    2016-10-01

    From the perspective of engineering geology, loess has long been considered as a homogeneous and porous material. It is commonly believed that water penetrates loess via pores and in some cases causing mass movements. However, several researchers have expressed doubts about this mechanism as a cause of slope failures in loess, and moreover the actual hydrological processes operating in loess deposits and their effect on slope failures have not been fully investigated. Here we present the results of an electrical resistivity survey of the Heifangtai loess terrace in northwestern China, designed to characterize the hydrological processes in loess slopes and their relationship with slope failures. The Heifangtai loess terrace is located on the fourth terrace of the Yellow River and consists of 57-m-thickness of aeolian loess. 2D and 3D electrical resistivity tomography (ERT) was used to monitor the movement of ground water before and after irrigation and rainfall events and the evolution of a sink hole in the toe of the landslide deposits. Our main findings are as follows: (1) Based on the 2D ERT results, the depth of infiltration into the thick unsaturated loess is not more than 5 m in the profile at the top of the landslide. (2) Electrical resistivity decreased as a result of water infiltration through sinkholes, and this process can increase the soil water content and induce soil liquefaction which can eventually result in land sliding. (3) Landslide deposits block the groundwater drainage channels through the loess, which results in the concentration of water in the toe of the landslide. Consequently, groundwater together with rainfall, triggers the failure of sinkholes or cracks, which may induce a continuing process of new slope failures at the sites of past landslide.

  16. Overpressure development and oil charging in the central Junggar Basin,Northwest China:Implication for petroleum exploration

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The Junggar Basin is one of the largest and most petroliferous superimposed petroleum basins in China. The central depression area has become the frontier field for petroleum exploration. The characteristics of potential source rocks and reservoir sandstones, and the pressure regime in the central Junggar Basin were studied. Permian shales are dominated by hydrogen-rich, oil-prone algal organic matter, and Jurassic mudstones are dominated by hydrogen-poor, higher-plant derived organic matter. These source rocks are widespread and have been mature for hydrocarbon generation, suggesting good to excellent exploration potential, both for crude oils and for natural gases. The deeply buried Jurassic sandstones usually have low porosity and permeability. However, sandstones beneath the Jurassic/Cretaceous unconformity display relatively high porosity and permeability, suggesting that meteoric water leaching had improved the quality of the sandstones. Overpressure developed over much of the central Junggar Basin. The overpressured rocks are characterized by slightly increased interval transit time, low sandstone permeability, increased organic matter maturity, and high relative hydrocarbon-gas contents. Mudstones in the overpressured system have quite the same clay mineral compositions as mudstones in the lower part of the normally pressured system. Overpressure generation in the central Junggar Basin is best to be explained as the result of hydrocarbon generation and fluid retention in low-permeability rocks. Petroleum generated from Permian and Jurassic source rocks could migrate laterally through preferential petroleum migration pathways and accumulated in structural traps or lithological traps in the overpressured system, or migrate vertically through faults/ hydraulic fractures into the overlying, normally pressured system and accumulate in structural or lithological traps. Therefore, commercial petroleum reservoirs could be potentially found in both the overpressured

  17. Overpressure development and oil charging in the central Junggar Basin,Northwest China:Implication for petroleum exploration

    Institute of Scientific and Technical Information of China (English)

    CAI XiYuan

    2009-01-01

    The Junggar Basin is one of the largest and most petroliferous superimposed petroleum basins in China.The central depression area has become the frontier field for petroleum exploration.The characteristics of potential source rocks end reservoir sandstones,and the pressure regime in the central Junggar Basin were studied.Permian shales are dominated by hydrogen-rich,oil-prone algal organic matter,and Jurassic mudstones are dominated by hydrogen-poor,higher-plant derived organic matter.These source rocks are widespread and have been mature for hydrocarbon generation,suggesting good to excellent exploration potential,both for crude oils and for natural gases.The deeply buried Jurassic sandstones usually have low porosity and permeability.However,sandstones beneath the Jurassic/Cretaceous unconformity display relatively high porosity and permeability,suggesting that meteoric water leaching had improved the quality of the sandstones.Overpressure developed over much of the central Junggar Basin.The overpressured rocks are characterized by slightly increased interval transit time,low sandstone permeability,increased organic matter maturity,and high relative hydrocarbon-gas contents.Mudstones in the overpressured system have quite the same clay mineral compositions as mudstones in the lower part of the normally pressured system.Overpressure generation in the central Junggar Basin is best-to be explained as the result of hydrocarbon generation and fluid retention in low-permeability rocks.Petroleum generated from Permian and Jurassic source rocks could migrate laterally through preferential petroleum migration pathways and accumulated in structural traps or lithological traps in the overpressured system,or migrate vertically through faults/hydraulic fractures into the overlying,normally pressured system and accumulate in structural or lithological traps.Therefore,commercial petroleum reservoirs could be potentially found in both the overpressured system,and in the normally

  18. Different Effects of Regional Species Pool on Plant Diversity between Forest and Grassland Biomes in Arid Northwest China.

    Science.gov (United States)

    Li, Liping; Liu, Yining; Wang, Xiangping; Fang, Jingyun; Wang, Qingchun; Zhang, Bengang; Xiao, Peigen; Mohammat, Anwar; Terwei, André

    2015-01-01

    Species pool hypothesis is broadly known and frequently tested in various regions and vegetation types. However it has not been tested in the arid Xinjiang region of China due to lack of data. Here with systematic data from references and field survey, we comprehensively examined species pool hypothesis in this region. Took species richness in 0.1° × 0.1° grid cells as regional species richness (RSR) which were obtained from the distribution maps of vascular plant species, and took species diversity of 190 and 103 plots in forest and grassland biomes across Xinjiang as local species richness (LSR), together with the digitalized soil pH and climate data, we tested the species pool hypothesis in this region. We found that: (1) the average RSR was higher in mountains than that in basins and it was negatively correlated with soil pH in mountains while positively correlated with soil pH in basins in Xinjiang; (2) RSR showed a positive correlation with mean annual precipitation (MAP) while showed a hump-shaped pattern with mean annual temperature (MAT); and the changing patterns of LSR were different for forest and grassland along the geographical and climate gradients; (3) LSR of forest was more affected by RSR than by climate, while on the contrary, LSR of grassland was more affected by climate than by RSR. Our results validated the species pool hypothesis in revealing that RSR had a significant role in shaping LSR patterns in addition to climate. We concluded that the relative effects of climate vs. RSR on LSR differed markedly between the forest and grassland communities across Xinjiang. Our results also showed that RSR revealed a contrasting relationship with soil pH in mountains and in basins, which might reflect differences in evolutionary processes of various habitats. In summary, our research systematically analyzed the correlation of species richness in regional and local scales in Xinjiang which provides more insights into the understanding of species pool

  19. Water consumption characteristics and water use efficiency of winter wheat under long-term nitrogen fertilization regimes in northwest China.

    Directory of Open Access Journals (Sweden)

    Yangquanwei Zhong

    Full Text Available Water shortage and nitrogen (N deficiency are the key factors limiting agricultural production in arid and semi-arid regions, and increasing agricultural productivity under rain-fed conditions often requires N management strategies. A field experiment on winter wheat (Triticum aestivum L. was begun in 2004 to investigate effects of long-term N fertilization in the traditional pattern used for wheat in China. Using data collected over three consecutive years, commencing five years after the experiment began, the effects of N fertilization on wheat yield, evapotranspiration (ET and water use efficiency (WUE, i.e. the ratio of grain yield to total ET in the crop growing season were examined. In 2010, 2011 and 2012, N increased the yield of wheat cultivar Zhengmai No. 9023 by up to 61.1, 117.9 and 34.7%, respectively, and correspondingly in cultivar Changhan No. 58 by 58.4, 100.8 and 51.7%. N-applied treatments increased water consumption in different layers of 0-200 cm of soil and thus ET was significantly higher in N-applied than in non-N treatments. WUE was in the range of 1.0-2.09 kg/m3 for 2010, 2011 and 2012. N fertilization significantly increased WUE in 2010 and 2011, but not in 2012. The results indicated the following: (1 in this dryland farming system, increased N fertilization could raise wheat yield, and the drought-tolerant Changhan No. 58 showed a yield advantage in drought environments with high N fertilizer rates; (2 N application affected water consumption in different soil layers, and promoted wheat absorbing deeper soil water and so increased utilization of soil water; and (3 comprehensive consideration of yield and WUE of wheat indicated that the N rate of 270 kg/ha for Changhan No. 58 was better to avoid the risk of reduced production reduction due to lack of precipitation; however, under conditions of better soil moisture, the N rate of 180 kg/ha was more economic.

  20. Organic geochemistry and petroleum geology, tectonics and basin analysis of southern Tarim and northern Qaidam basins, northwest China

    Science.gov (United States)

    Hanson, Andrew Dean

    Organic geochemistry of oils from the Tarim basin, NW China, distinguish at least seven genetic groups of oils. The largest group are derived from Middle-Upper Ordovician anoxic slope-facies marls coincident with the margins of structural uplifts. Other groups include non-marine derived oils in the Luntai uplift, from southwest Tarim, in the Kuqa depression, and west of the Bachu uplift. A seep sample from west of Kashi clusters with Luntai oils. These results suggest that numerous source-rock horizons occur, but they are really restricted. Organic geochemistry of oils from northern Qaidam defines a family of hypersaline, anoxic lacustrine derived oils. Cenozoic outcrop samples from northern Qaidam are too organic lean to be of source quality, but dark laminated upper Oligocene mudstones from the Shi 28 well are of fair to good quality. Biomarkers provide a good correlation between the oils and the core samples. Organic matter is from algae and bacteria and lacks terrestrial material. Hydrocarbons are contained in upper Oligocene, Miocene, and Pliocene reservoirs. Eight oils are from NW Qaidam, but one sample comes from NE Qaidam, an area previously believed to only produce oils derived from Jurassic source rocks. Thus an unidentified Cenozoic source rock occurs in NE Qaidam. Thermal modeling indicates generation occurred in northwestern Qaidam within the last 3 million years, agreeing with observed low maturity biomarker parameters. Cenozoic stratigraphy in northern Qaidam and southern Tarim basins record the tectonic history of the surrounding structural/topographic elements. Paleocurrents record flow away from adjacent ranges from the Miocene to the present. Provenance data tie sediments to adjacent structural elements. Petrography indicates increasingly immature sandstones in Miocene and younger sediments relative to pre-Miocene samples. Apatite fission-track results from southeastern Tarim yield a cooling age of 17 +/- 1 Ma indicative of unroofing since at

  1. Water consumption characteristics and water use efficiency of winter wheat under long-term nitrogen fertilization regimes in northwest China.

    Science.gov (United States)

    Zhong, Yangquanwei; Shangguan, Zhouping

    2014-01-01

    Water shortage and nitrogen (N) deficiency are the key factors limiting agricultural production in arid and semi-arid regions, and increasing agricultural productivity under rain-fed conditions often requires N management strategies. A field experiment on winter wheat (Triticum aestivum L.) was begun in 2004 to investigate effects of long-term N fertilization in the traditional pattern used for wheat in China. Using data collected over three consecutive years, commencing five years after the experiment began, the effects of N fertilization on wheat yield, evapotranspiration (ET) and water use efficiency (WUE, i.e. the ratio of grain yield to total ET in the crop growing season) were examined. In 2010, 2011 and 2012, N increased the yield of wheat cultivar Zhengmai No. 9023 by up to 61.1, 117.9 and 34.7%, respectively, and correspondingly in cultivar Changhan No. 58 by 58.4, 100.8 and 51.7%. N-applied treatments increased water consumption in different layers of 0-200 cm of soil and thus ET was significantly higher in N-applied than in non-N treatments. WUE was in the range of 1.0-2.09 kg/m3 for 2010, 2011 and 2012. N fertilization significantly increased WUE in 2010 and 2011, but not in 2012. The results indicated the following: (1) in this dryland farming system, increased N fertilization could raise wheat yield, and the drought-tolerant Changhan No. 58 showed a yield advantage in drought environments with high N fertilizer rates; (2) N application affected water consumption in different soil layers, and promoted wheat absorbing deeper soil water and so increased utilization of soil water; and (3) comprehensive consideration of yield and WUE of wheat indicated that the N rate of 270 kg/ha for Changhan No. 58 was better to avoid the risk of reduced production reduction due to lack of precipitation; however, under conditions of better soil moisture, the N rate of 180 kg/ha was more economic.

  2. 西北地区赫刺螨亚科和鼠刺螨亚科小志%Small-sinica of Hirstionyssinae Evans et Till and Myonyssinae Tiraboschi in northwest China

    Institute of Scientific and Technical Information of China (English)

    刘增加; 张继军

    2011-01-01

    目的 研究西北地区厉螨科的种类与地理分布.方法 宿主体检螨法、巢穴检螨法和文献资料收集.结果 记述了西北地区赫刺螨亚科和鼠刺螨亚科2亚科2属28种:其中赫刺螨亚科1属27种,赫刺螨属27种;鼠刺螨亚科1属1种,鼠刺螨属1种.结论 明确了西北地区赫刺螨亚科和鼠刺螨亚科的种类与分布,为深入研究与防控提供了科学依据.%Objective To study features of species and the geographical distribution of Laelapidae Berlese in northwest China.Methods Using the methods of mite inspection of host surface and nest.Results Hirstionyssinae Evans et Till and Myonyssinae Tiraboschi in the northwest China belonging to 2 genera and a total of 28 species had been recorded, of which 27 species of Genus Hirstionyssus Fonseca in Hirstionyssinae Evans et Till and 1 species of Genus Myonyssus Tiraboschi in Myonyssinae Tiraboschi of Laelapidae Berlese.Conclusion The results provide scientific basis for more study and preventing and controlling by grasping Hirstionyssinae Evans et Till and Myonyssinae Tiraboschi of Laelapidae Berlese in the northwest China.

  3. Trends in population blood pressure and prevalence, awareness, treatment, and control of hypertension among middle-aged and older adults in a rural area of Northwest China from 1982 to 2010.

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    Yaling Zhao

    Full Text Available OBJECTIVES: To assess trends in average blood pressure levels and prevalence, awareness, treatment, and control of hypertension among adults in a rural area of Northwest China, and to determine associated risk factors. METHODS: Four cross-sectional population-based surveys were conducted between 1982 and 2010 among randomly selected adults in rural areas of Hanzhong, in Northwest China. Data on blood pressure, body mass index, family history of hypertension, and socio-demographic and lifestyle characteristics were collected in similar way by trained investigators in four surveys. Data of 8575 participants aged 35-64 years was analyzed. Averages and proportions were adjusted for age and sex. RESULTS: Average blood pressure in the population has increased since 1982 from 76.9 mm Hg to 79.6 mm Hg in 2010 (diastolic and from 120.9 to 129.7 mm Hg (systolic. Prevalence of hypertension increased from 18.4% in 1982 to 30.5% in 2010, and awareness of hypertension increased from 16.8% to 38.4% in 2010. Treatment of hypertension increased from 1.0% in 1982 to 17.4% in 2010, and control of hypertension increased from 0.1% in 1982 to 3.5% in 2010. All these gradients were statistically significant (P<0.01 for trend. Population blood pressure and prevalence, awareness and treatment of hypertension were positively associated with increasing age, body mass index and having family history of hypertension. CONCLUSIONS: Average blood pressure levels and the prevalence, awareness, treatment and control of hypertension among adults in rural areas of Hanzhong have increased since 1982. However, awareness, treatment and control rates remain low. Public health programs and practical strategies are required to improve prevention and control of hypertension in rural Northwest China. In particular, attention should be given to the elderly and obese, and to those with a family history of hypertension, while raising awareness and treatment among younger adults.

  4. 西北地区城市化进程对产业结构演变的驱动效应研究%Driving effect of the industrial structure development in the process ofurbanization in northwest China

    Institute of Scientific and Technical Information of China (English)

    马子量

    2016-01-01

    基于2005-2012年西北地区51个市(州/地)的面板数据,利用相关指标测度了西北地区城市化进程对产业结构演变的驱动效应,在对其时空演化基本趋势把握的基础之上,利用空间自相关检验及空间计量方法对其空间相关性和时空驱动路径进行了分析.研究结果显示:①西北地区城市化进程对产业结构演变的驱动效应整体程度较低,但大部分市(州/地)存在逐步增强趋势,城市化进程对产业结构演变的驱动效应日益凸显;②西北地区城市化进程对产业结构演变的驱动效应存在块状联接分布,且城市密集区的驱动效应增长较城市稀疏区更为明显,空间自相关检验显示西北地区城市化进程对产业结构演变的驱动效应空间相似值集聚,且低值集聚强于高值集聚,同时驱动效应的空间正向相关性呈下降趋势;③西北地区城市化进程中的经济发展水平、区域开发强度、区域开放程度以及产业集聚等因素对产业结构的演变具有一定的驱动效应,但西北地区经济发展水平低、财政支付能力弱、外向型程度不高和产业集聚水平低的现实,在很大程度上制约了驱动效应的强度;④本地城市化进程中的多重因素在不断驱动自身产业结构演变的同时,还存在驱动效应的空间交互影响,经济发展水平的空间溢出对产业结构演变有着最为强烈的正向驱动,但区域开发强度、区域开放程度以及产业集聚存在的空间竞争效应又在很大程度上弱化了这一驱动效应.未来在通过加速城市化综合进程进一步推动西北地区产业结构高级化的基础上,还需加强西北地区城际间的协调联动发展.%Based on the panel data of 51 cities(states and regions) in the northwest China from 2005 to 2012, the driving effect of the industrial structure development in the process of urbanization was measured by using the correlation index.Based on

  5. Correlation slopes of GEM / CO, GEM / CO2, and GEM / CH4 and estimated mercury emissions in China, South Asia, Indochinese Peninsula, and Central Asia derived from observations in northwest and southwest China

    Science.gov (United States)

    Fu, X. W.; Zhang, H.; Lin, C.-J.; Feng, X.; Zhou, L. X.; Fang, S. X.

    2014-09-01

    Correlation analysis between atmospheric mercury (Hg) and other trace gases are useful for identification of sources and constraining regional estimated Hg emissions. Emissions of Hg in Asia contribute significantly to the global budget of atmospheric Hg. However, due to the lack of reliable data on the source strength, large uncertainties remain in the emission inventories of Hg in Asia. In the present study, we calculated the correlation slopes of GEM / CO, GEM / CO2, and GEM / CH4 for mainland China, South Asia, Indochinese Peninsula, and Central Asia using the ground-based observations at three remote sites in northwest and southwest China, and applied the values to estimate GEM emissions in the four source regions. The geometric mean of the GEM / CO correlation slopes for mainland China, South Asia, Indochinese Peninsula, and Central Asia were 7.3 ± 4.3, 7.8 ± 6.4, 7.8 ± 5.0, and 13.4 ± 9.5 pg m-3 ppb-1, respectively. The values in the same source regions were 240 ± 119, 278 ± 164, 315 ± 289 pg m-3 ppm-1 for the GEM / CO2 correlation slopes; and 33.3 ± 30.4, 27.4 ± 31.0, 23.5 ± 15.3, and 20.5 ± 10.0 pg m-3 ppb-1 for the GEM / CH4 correlation slopes, respectively. These values were the first reported correlation slopes of GEM / CO, GEM / CO2, and GEM / CH4 in four important source regions of Asia except the GEM / CO ratios in mainland China. The correlation slopes of GEM / CO, GEM / CO2 and GEM / CH4 in Asia were relatively higher than those observed in Europe, North America and South Africa, which may highlight GEM emissions from non-ferrous smelting, mercury mining, natural sources and historical deposited mercury (re-emission) in Asia. Using the observed GEM / CO and GEM / CO2 slopes, and the recently reported emission inventories of CO and CO2, the annual GEM emissions in mainland China, South Asia, Indochinese Peninsula, and Central Asia were estimated to be in the ranges of 1071-1187 t, 340-470 t, 125 t, and 54-90 t, respectively. The estimate

  6. Correlation slopes of GEM / CO, GEM / CO2, and GEM / CH4 and estimated mercury emissions in China, South Asia, Indochinese Peninsula, and Central Asia derived from observations in northwest and southwest China

    Directory of Open Access Journals (Sweden)

    X. W. Fu

    2014-09-01

    Full Text Available Correlation analysis between atmospheric mercury (Hg and other trace gases are useful for identification of sources and constraining regional estimated Hg emissions. Emissions of Hg in Asia contribute significantly to the global budget of atmospheric Hg. However, due to the lack of reliable data on the source strength, large uncertainties remain in the emission inventories of Hg in Asia. In the present study, we calculated the correlation slopes of GEM / CO, GEM / CO2, and GEM / CH4 for mainland China, South Asia, Indochinese Peninsula, and Central Asia using the ground-based observations at three remote sites in northwest and southwest China, and applied the values to estimate GEM emissions in the four source regions. The geometric mean of the GEM / CO correlation slopes for mainland China, South Asia, Indochinese Peninsula, and Central Asia were 7.3 ± 4.3, 7.8 ± 6.4, 7.8 ± 5.0, and 13.4 ± 9.5 pg m−3 ppb−1, respectively. The values in the same source regions were 240 ± 119, 278 ± 164, 315 ± 289 pg m−3 ppm−1 for the GEM / CO2 correlation slopes; and 33.3 ± 30.4, 27.4 ± 31.0, 23.5 ± 15.3, and 20.5 ± 10.0 pg m−3 ppb−1 for the GEM / CH4 correlation slopes, respectively. These values were the first reported correlation slopes of GEM / CO, GEM / CO2, and GEM / CH4 in four important source regions of Asia except the GEM / CO ratios in mainland China. The correlation slopes of GEM / CO, GEM / CO2 and GEM / CH4 in Asia were relatively higher than those observed in Europe, North America and South Africa, which may highlight GEM emissions from non-ferrous smelting, mercury mining, natural sources and historical deposited mercury (re-emission in Asia. Using the observed GEM / CO and GEM / CO2 slopes, and the recently reported emission inventories of CO and CO2, the annual GEM emissions in mainland China, South Asia, Indochinese Peninsula, and Central Asia were estimated to be in the ranges of 1071–1187 t, 340–470 t, 125 t, and 54

  7. Epidemiological investigation of fatty liver disease in Northwest China%西北地区脂肪性肝病的流行病学调查研究

    Institute of Scientific and Technical Information of China (English)

    延华; 鲁晓岚; 高艳琼; 罗金燕

    2015-01-01

    Objective To describe the incidence and related risk factors of fatty liver disease in the general population of Northwest China.Methods The study was a cross-sectional survey with multiplestage stratified cluster and random sampling.All participants were 18 years or older and resided in northwest provinces of China.Demographic and behavioral data was gathered by questionnaire.Clinical data such as height,body weight,waist circumference,biochemical function (standard tests) and liver status (ultrasonographic examination) were also collected.Results Among the 2 300 total study participants,1 523 were habitual drinkers (total drinking rate:66.2%).This population of drinkers was composed almost exclusively of males.There were 201 cases of alcoholic liver disease (total prevalence:8.7%),represented by mild alcoholic injury (prevalence:4.2%),alcoholic fatty liver (3.8%),alcoholic hepatitis (0.5%),and alcoholic cirrhosis (0.3%).When examined according to provinces of residence,the prevalence of alcoholic liver disease followed this pattern:Shaanxi (14.0%),Gansu (8.6%),and Xinjiang autonomous region (5.0%).Of the total 337 cases of nonalcoholic fatty liver disease (total prevalence:14.7%),the prevalence by province was:Shaanxi (18.5%),Gansu (10.3%),and Xinjiang autonomous region (16.6%).Individuals with alcoholic liver disease had significantly higher mean age (years),body weight,body mass index (BMI),waist circumference,average daily alcohol intake,and level of aspartate aminotransferase (AST),and alanine aminotraasferase (ALT) (vs.those with no liver disease,P < 0.05).Individuals with nonalcoholic fatty liver disease had significantly higher mean age (years),height,body weight,BMI,waist circumference,level of AST and ALT,and presence of obesity,abdominal obesity,hyperlipidemia,diabetes mellitus and hypertension (vs.those with no liver disease,P < 0.05).Multiple logistic regression demonstrated that alcoholic liver disease was closely

  8. Kinematics of a giant slow-moving landslide in Northwest China: Constraints from high resolution remote sensing imagery and GPS monitoring

    Science.gov (United States)

    Jiang, Shu; Wen, Bao-Ping; Zhao, Cheng; Li, Rui-Dong; Li, Zhi-Heng

    2016-06-01

    Slow-moving landslides generally are long-lived and characterized by continuous movement with some fluctuation in sliding rate following changes of environmental factors, such as rainfall and earthquake. Analysis on kinematics of this type of landslide is essential for understanding its mechanism and identifying causal factors controlling its movement behavior. This paper presents a study on kinematics of a giant slow-moving landslide in northwest China, called the Xieliupo landslide, which is about 72 × 106 m3 in volume and has been slowly moving for more than 100 years. This study is conducted using archival high resolution remote sensing images from multi-sources over a period about 43 years and the data from 15-month GPS monitoring. Six sets of multi-source remote sensing images in 1969, 1971, 2004, 2008, 2010 and 2012 with spatial resolution higher than 2.5 m were used, and GPS monitoring data were recorded from September 2012 to December 2013. Obvious geomorphologic changes identified from the images in 1971 and 2004 confirm that this landslide did move slowly in the past. Quantitative analysis reveals that movement of the landslide was persistent and behaved in a block by block mode with the greatest and the least velocities in its middle and lower parts, respectively. Distance measurement between the homologous point pairs on the orthorectified images in 2005, 2010 and 2012 indicates that annual ground displacement of the landslide ranged from 0.52 m to 6.54 m in the seven years. GPS monitoring data shows that the landslide ground displacement in the 15 months varied from 0.49 m to 2.91 m, and annually between 0.39 m and 2.33 m, with a rather uniform movement pattern as identified using the remote sensing images. GPS monitoring results also reveal that the landslide movement is intermittent inter-annually. It is further discussed that movement behavior of the landslide is largely controlled by its topography with great influence of the active fault along

  9. Changes in Socioeconomic Inequality of Low Birth Weight and Macrosomia in Shaanxi Province of Northwest China, 2010-2013: A Cross-sectional Study.

    Science.gov (United States)

    Pei, Leilei; Kang, Yijun; Zhao, Yaling; Cheng, Yue; Yan, Hong

    2016-02-01

    Socioeconomic disparities in birth weights (BWs) are associated with lifelong differences in health and productivity. Understanding socioeconomic disparities in BW is presently of concern to develop public health interventions that promote a good start in life in Northwest China. In the study, our objective is to investigate the socioeconomic disparities in low and high BW from 2010 to 2013 in this region.Those single live births were recruited using a stratified multistage sampling method in Shaanxi province from August to December 2013. Data were collected with a structured questionnaire and a review of birth certificates. Socioeconomic status (SES) was stratified based on the calculated household wealth index. Prevalence differences (PDs) and concentration indices (CIs) were used to depict the SES inequality of low BW (LBW) and macrosomia.Information for 28722 single live births born were obtained in Shaanxi province. From 2010 to 2013, the overall rates of LBW decreased, and the difference in LBW across differing SES groups decreased by 0.7% (boys, 0.4%; girls, 0.8%). From 2010 to 2013, the overall rates of macrosomia increased by 14.3% (boys, 17.5%; girls, 7.8%), whereas the PDs in macrosomia across various SES groups remained unchanged. From 2010 to 2013, concentration indices for SES inequalities in LBW and macrosomia confirmed the results shown by differences in prevalence. Compared with mothers of high SES, those in low SES group were significantly older, less educated, engaged in farming with less availabile healthcare, and engaged in unhealthy lifestyles (eg, exposure to secondhand smoke) during pregnancy, regardless of the baby's sex.From 2010 to 2013, in Shaanxi province, the negative association between socioeconomic status and LBW weakened. Rates of macrosomia were higher in those of high SES, but the SES disparities varied insignificantly over the same time. Our findings may provide valuable insights to direct healthcare policies for pregnant women

  10. Chemical composition, sources, and processes of urban aerosols during summertime in northwest China: insights from high-resolution aerosol mass spectrometry

    Science.gov (United States)

    Xu, J.; Zhang, Q.; Chen, M.; Ge, X.; Ren, J.; Qin, D.

    2014-12-01

    An Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was deployed along with a scanning mobility particle sizer (SMPS) and a multi-angle absorption photometer (MAAP) to measure the temporal variations of the mass loading, chemical composition, and size distribution of submicron particulate matter (PM1) in Lanzhou, northwest China, during 11 July-7 August 2012. The average (PM1 mass concentration including non-refractory (PM1 (NR-(PM1) measured by HR-ToF-AMS and black carbon (BC) measured by MAAP during this study was 24.5 μg m-3 (ranging from 0.86 to 105 μg m-3), with a mean composition consisting of 47% organics, 16% sulfate, 12% BC, 11% ammonium, 10% nitrate, and 4% chloride. Organic aerosol (OA) on average consisted of 70% carbon, 21% oxygen, 8% hydrogen, and 1% nitrogen, with the average oxygen-to-carbon ratio (O / C) of 0.33 and organic mass-to-carbon ratio (OM / OC) of 1.58. Positive matrix factorization (PMF) of the high-resolution organic mass spectra identified four distinct factors which represent, respectively, two primary OA (POA) emission sources (traffic and food cooking) and two secondary OA (SOA) types - a fresher, semi-volatile oxygenated OA (SV-OOA) and a more aged, low-volatility oxygenated OA (LV-OOA). Traffic-related hydrocarbon-like OA (HOA) and BC displayed distinct diurnal patterns, both with peak at ~ 07:00-11:00 (BJT: UTC +8), corresponding to the morning rush hours, while cooking-emission related OA (COA) peaked during three meal periods. The diurnal profiles of sulfate and LV-OOA displayed a broad peak between ~ 07:00 and 15:00, while those of nitrate, ammonium, and SV-OOA showed a narrower peak between ~ 08:00-13:00. The later morning and early afternoon maximum in the diurnal profiles of secondary aerosol species was likely caused by downward mixing of pollutants aloft, which were likely produced in the residual layer decoupled from the boundary layer during nighttime. The mass spectrum of SV-OOA was

  11. Variations in the concentration and isotopic composition of nitrate nitrogen in wet deposition and their relation with meteorological conditions in Xi'an city, Northwest China

    Science.gov (United States)

    Xing, M.; Liu, W.

    2012-12-01

    The characterization of N isotopes in NO3- is an effective method to determine NO3- sources and NOX transformation mechanisms. Xi'an city is located in a semi-arid to arid region and is representative of most cities in the north and Northwest of China. Few studies have been carried out on N isotopes in wet deposition of this region. In this study, 29 wet deposition samples were collected from Xi'an city in northwestern China between March 2008 and May 2009 and analyzed for their volume-weighted NO3- and NH4+ concentrations and N isotopic compositions. Volume-weighted mean concentrations were 3.9 μmol L-1 for NO3- and 13.5 μmol L-1 for NH4+. The wet deposition samples showed pronounced seasonal variation in the N isotopic composition of NO3- with δ15N-NO3- ranging from -2.0‰ to +9.2‰ over the course of a year, with a mean value of +2.6 ± 2.6‰. Higher δ15N-NO3- values were observed in the cool season (November-May, +3.8‰) than in the warm season (June-October, +1.0‰). In autumn and winter in particular, the mean δ15N-NO3- values were clearly different (+0.9‰ and +6.7‰, respectively). Various factors are shown to lead to variation in the δ15N-NO3- values in wet deposition. One effect is changing ratios of N derived from agricultural/soil sources (low δ15N-NO3-, dominant in the warm season) and fossil fuel-derived NOX (high δ15N-NO3-, relatively more important in the cool season). However, in the cool season δ15N-NO3- unexpectedly shows a strong negative correlation with SO2 concentration, which should correlate with fossil fuel combustion inputs. This may be explained by interactions of N-species with other atmospheric pollutants. The results also suggest that temperature may be a significant factor affecting δ15N-NO3-. The NOX reacts in different ways depending on temperature, leading to a correlation of δ15N-NO3- with temperature. Moreover, the effects of dilution cannot be neglected here, as there is clear seasonal variation in

  12. The Administration of the Ethnic Regions in Northwest China during the Reign of the Mongolian Yuan Dynasty%蒙元对西北各民族地区的经营设治

    Institute of Scientific and Technical Information of China (English)

    高劲松

    2000-01-01

    In Northwest China, during the reign of the Mongolian Yuan Dynasty, ethnic problems were complex, migration was frequent, and ethnic division and reunion became prevalent. Political instability and disruption propelled the Central Government to carry out urgent measures. Under the leadership of the princes, in Gansu Province, administrative organs at different levels were established, roads were opened and cultivation improved. These measures and practices strengthened the political relationship between the local regions and the Central Government and consolidated the unity of Northwest China.%蒙元统治时期的西北,民族情况复杂,各民族的迁徙对流频繁,民族间的分化与重组相互交叉,政治上的统一与分裂变化无常,中央政府通过亲王出镇、建立甘肃行中书省和行枢密院、设置站赤、打开交通、开展屯田垦殖等一系列措施,加强了地方与元王朝中央的政治联系,巩固了西部边疆民族地区的统一。

  13. 中国西北大旱年发生概率的统计推断%A Statistical Inference from Probability of the Worst DroughtYear to Occur in the Northwest China

    Institute of Scientific and Technical Information of China (English)

    栗珂; 赵东; 杨碧轩; 郭宏武; 高炬

    2001-01-01

    Based on the data of the classes of flood/drought about fivehundred years in northwest China, using the theoretical model of Bernoulli test and others, the character of probability was studied for the worst drought to occur, the statistical rule of the worst drought year to was occurred to be obtained. In the background of the climate getting warm over the world, the result of the statistical inference of probability of the worst drought year will occur to be given in the 21th century in northwest China.%根据中国西北近500a旱涝等级资料,用Bernoulli试验等理论模式,对大旱年发生的概率特征进行了研究,得出大旱年发生的统计规律。在全球气候变暖的大背景下,给出了21世纪中国西北大旱年发生概率的统计推断结果。

  14. Fur Trade in Northwest China and Economy Changes of Rear Area during the War of Resistance against Japan%抗战时期西北皮毛贸易与大后方经济变动

    Institute of Scientific and Technical Information of China (English)

    谭刚

    2012-01-01

    皮毛是西北地区重要的畜牧产品。近代以来,随着天津的开埠通商,在天津口岸的经济辐射作用下,大量西北皮毛通过黄河水运汇集至包头后再通过平绥铁路运至天津出口美英等国,皮毛成为西北最重要的出口物资,大量西北皮毛的出口也成为西北地区皮毛业外向化的重要表现。但抗战爆发以后,西北皮毛贸易发生了巨大变化。首先,西北皮毛出口运输路线改为向西汇集兰州后再通过甘新公路或甘新大道运至猩猩峡出口苏联,使得苏联取代战前美国成为中国最大皮毛进口国,这也直接推动了战时中苏易货贸易的发展。其次,由于战时西北皮毛出口运输较战前出口运输路途艰险,加上战时出口市场萎缩等原因,造成战时西北皮毛出口量较战前减少。战时西北皮毛出口量的减少,迫使部分皮毛出口转内销,西北皮毛业从战前外向化开始转为战时内向化。西北皮毛内销数量的增加,也推动了大后方毛纺织业的发展。因此,战时西北皮毛业的内向化一定程度上为战时大后方经济的发展积累了新的动力因素。%Fur is the important product of animal husbandry in Northwest China.With the opening and development of Tianjin trade port in modern times,large amounts of fur products from Northwest China were transported to Baotou by the Yellow River and then to Tianjin through the Bei ping-Suiyuan railway where exported to the United States and the United Kingdom and so on.Therefore fur has become the most important export goods in Northwest China,which is the clear example of export-oriented fur industry in Northwest China.But after the outbreak of Anti-Japanese war,fur trade in Northwest China has undergone tremendous changes.First of all,the fur exports of transport routes transferred to Lanzhou,and then along the Gansu-Xinjiang highway or Gansu-Xinjiang avenue to Xingxing gap where exported to the Soviet Union,thus the

  15. 关于西北地区的自然灾害链%Analysis of Natural Disaster Chain in Northwest China

    Institute of Scientific and Technical Information of China (English)

    贾慧聪; 王静爱; 杨洋; 潘东华; 杨佩国; 张万昌

    2016-01-01

    Based on the disaster system theory,according to Chinese Provincial Newspapers Disaster Database (1949-2005),major disaster chains in Northwest China are built:drought disaster chain (divided into high tem-perature-drought chain,drought-pests-disease disaster chain,and drought-wind-sandstorm chain),earthquake dis-aster chain and cold-snow disaster chain.The results show that:less precipitation,high latitude,widespread des-ert,mountains and basins,plateaus and plains and other factors may lead to drought disaster chains.The disaster situation amplified with the processing of disaster chains,increased by the vulnerability of hazard-affected bodies. It is suggested that water resource protection be strengthened in the upstream mountainous arid areas,desertification and desertification be combated in the semi-arid steppe regions,and soil erosion be prevented and controlled in the Yellow River Basin.Taking the earthquake disaster and cold-snow disaster chain as the analysis cases,the corre-sponding mitigation measures are proposed to provide a scientific basis for disaster mitigation for governments.%基于灾害系统理论,根据中国省级报刊灾害数据库(1949-2005年),构建了我国西北地区主要的灾害链:干旱灾害链(分为高温-干旱灾害链、旱灾-虫灾-病害灾害链、旱灾-大风-沙尘暴灾害链)、地震灾害链和寒潮-雪灾灾害链的成灾模式。分析表明:降水少、纬度高、沙漠戈壁广布、山脉与盆地、高原与平川相间等是旱灾灾害链发生、发展的主要原因,灾情随灾害链过程放大,受承灾体脆弱性累积加重。提出干旱内陆区的上游山区加强水源保护,半干旱草原区防治荒漠化、沙化,黄河流域中上游区防治水土流失等区域模式。同时以案例形式分析了地震灾害链和寒潮-雪灾灾害链的致灾、成灾模式,提出了相应的减灾对策,为减灾提供科学依据。

  16. The disastrous effects of salt dust deposition on cotton leaf photosynthesis and the cell physiological properties in the Ebinur Basin in Northwest China.

    Directory of Open Access Journals (Sweden)

    Jilili Abuduwaili

    Full Text Available Salt dust in rump lake areas in arid regions has long been considered an extreme stressor for both native plants and crops. In recent years, research on the harmful effects of salt dust on native plants has been published by many scholars, but the effect on crops has been little studied. In this work, in order to determine the impact of salt dust storms on cotton, we simulated salt dust exposure of cotton leaves in Ebinur Basin in Northwest China, and measured the particle sizes and salt ions in the dust, and the photosynthesis, the structure and the cell physiological properties of the cotton leaves. (1 Analysis found that the salt ions and particle sizes in the salt dust used in the experiments were consistent with the natural salt dust and modeled the salt dust deposition on cotton leaves in this region. (2 The main salt cations on the surface and inside the cotton leaves were Na+, Ca2+, Cl- and SO42-, while the amounts of CO3- and HCO3- were low. From the analysis, we can order the quantity of the salt cations and anions ions present on the surface and inside the cotton leaves as Na+>Ca2+>Mg2+>K+ and Cl->SO42->HCO3->CO3-, respectively. Furthermore, the five salt dust treatment groups in terms of the total salt ions on both the surface and inside the cotton leaves were A(500g.m-2>B(400g.m-2>C(300g.m-2>D(200g.m-2>E(100g.m-2>F(0g.m-2. (3The salt dust that landed on the surface of the cotton leaves can significantly influence the photosynthetic traits of Pn, PE, Ci, Ti, Gs, Tr, WUE, Ls, φ, Amax, k and Rady of the cotton leaves. (4Salt dust can significantly damage the physiological functions of the cotton leaves, resulting in a decrease in leaf chlorophyll and carotenoid content, and increasing cytoplasmic membrane permeability and malondialdehyde (MDA content by increasing the soluble sugar and proline to adjust for the loss of the cell cytosol. This increases the activity of antioxidant enzymes to eliminate harmful materials, such as the

  17. The disastrous effects of salt dust deposition on cotton leaf photosynthesis and the cell physiological properties in the Ebinur Basin in Northwest China.

    Science.gov (United States)

    Abuduwaili, Jilili; Zhaoyong, Zhang; Feng qing, Jiang; Dong wei, Liu

    2015-01-01

    Salt dust in rump lake areas in arid regions has long been considered an extreme stressor for both native plants and crops. In recent years, research on the harmful effects of salt dust on native plants has been published by many scholars, but the effect on crops has been little studied. In this work, in order to determine the impact of salt dust storms on cotton, we simulated salt dust exposure of cotton leaves in Ebinur Basin in Northwest China, and measured the particle sizes and salt ions in the dust, and the photosynthesis, the structure and the cell physiological properties of the cotton leaves. (1) Analysis found that the salt ions and particle sizes in the salt dust used in the experiments were consistent with the natural salt dust and modeled the salt dust deposition on cotton leaves in this region. (2) The main salt cations on the surface and inside the cotton leaves were Na+, Ca2+, Cl- and SO42-, while the amounts of CO3- and HCO3- were low. From the analysis, we can order the quantity of the salt cations and anions ions present on the surface and inside the cotton leaves as Na+>Ca2+>Mg2+>K+ and Cl->SO42->HCO3->CO3-, respectively. Furthermore, the five salt dust treatment groups in terms of the total salt ions on both the surface and inside the cotton leaves were A(500g.m-2)>B(400g.m-2)>C(300g.m-2)>D(200g.m-2)>E(100g.m-2)>F(0g.m-2). (3)The salt dust that landed on the surface of the cotton leaves can significantly influence the photosynthetic traits of Pn, PE, Ci, Ti, Gs, Tr, WUE, Ls, φ, Amax, k and Rady of the cotton leaves. (4)Salt dust can significantly damage the physiological functions of the cotton leaves, resulting in a decrease in leaf chlorophyll and carotenoid content, and increasing cytoplasmic membrane permeability and malondialdehyde (MDA) content by increasing the soluble sugar and proline to adjust for the loss of the cell cytosol. This increases the activity of antioxidant enzymes to eliminate harmful materials, such as the intracellular

  18. 西北地区岩画视阈中的原始体育释读%Study of Ancient Sports Rock-painting in North-west China

    Institute of Scientific and Technical Information of China (English)

    丛振

    2012-01-01

    A great number of rock-painting extensively exist in the north-west district of China, among which some painting express the original sports images with strong repress ntativeness. The thesis aims to survey and explain the features of sports origin and evolution, resurvey the sports history of the north-west district, especially the origin and development of national sports history, from the four-dimensional relation between remains, human being, time and space by combining the researches on rock-painting, history, archaeology, iconology and sports, in light of the images with sports features in the prehistoric rock-painting of the north-west district and on the basis of image analysis and relative literature research.%西北地区岩画数量丰富,分布广泛,很多岩画图像中都表现出原始的体育运动形态,具有很强的代表性。在坚持图像分析与研读相关文献相结合的基础上,借助于西北地区史前岩画中具有体育特征的图像,把岩画学、历史学、考古学、图像学与体育学研究相结合,从遗存、人、时、空这四维关系观察和解释体育的起源、发展演变特征,从图像的视角重新观照西北地区体育历史,尤其是民族体育历史的起源发展。

  19. 内陆河流域用水结构与产业结构双向优化仿真模型%Mutual optimization of water utilization structure and industrial structure in arid inland river basins of Northwest China

    Institute of Scientific and Technical Information of China (English)

    鲍超; 方创琳; 陈凡

    2006-01-01

    Water is a key restricting factor of the economic development and eco-environmental protection in arid inland river basins of Northwest China. Although water supplies are short, the water utilization structure and the corresponding industrial structure are unbalanced. We constructed a System Dynamic Model for mutual optimization based on the mechanism of their interaction. This model is applied to the Heihe River Basin where the share of limited water resources among ecosystem, production and human living is optimized. Results show that, by mutual optimization, the water utilization structure and the industrial structures fit in with each other. And the relationships between the upper, middle and lower reaches of the Heihe River Basin can be harmonized. Mutual benefits of ecology, society and economy can be reached, and a sustainable ecology-production-living system can be obtained. This study gives a new insight and method for the sustainable utilization of water resources in arid inland river basins.

  20. 冰川加剧消融对我国西北干旱区的影响及其适应对策%Impact of Intensive Glacier Ablation on Arid Regions of Northwest China and Its Countermeasure

    Institute of Scientific and Technical Information of China (English)

    张九天; 何霄嘉; 上官冬辉; 钟方雷; 刘时银

    2012-01-01

    西北干旱区是我国生态最脆弱的地区之一,也是国家安全和生态安全的核心区.冰川是西北干旱区的"固体水库",高山冰雪融水一直是当地赖以生存和发展的重要水源,是该地区独特的绿洲经济的命脉.在气候变暖的大背景下,西北干旱区冰川加剧消融退缩,冰川数量和规模均呈减少趋势.未来冰川将进一步萎缩,冰川融水对河流补给将有显著变化.冰川加剧消融已严重影响到该地区水资源变化格局、农业可持续发展和生态系统稳定,对现有水资源管理与灾害防治等对策与措施提出巨大挑战.应采取从转变经济发展用水和管理理念,到提高适应冰川消融的水利建设、加强防灾与预测技术研究等方面的积极探索适应对策,以应对气候变暖背景下冰川加剧消融给西北地区带来的挑战.%Arid Regions of Northwest China are most ecologically vulnerable regions and the core regions of national security and ecological security.The glaciers in the arid regions of Northwest China are called solid reservoirs.Melting water from glaciers is not only important water sources for the local development,but also the lifeblood of the local unique oasis economy.In the context of climate warming,the glaciers in arid regions of Northwest China ablate extremely and their number and size are decreasing.Intensive glacier ablation has seriously affected the pattern of regional water resources,the sustainable development of agriculture and the ecosystem stability,which challenge the existing water resources management system and disaster prevention measures.The development and management ideas should be changed,the capacity building of adaptation to the glacier retreat should be improved,and the technological research should be strengthened,in order to actively explore the adaptive countermeasures against the challenges of glacier retreat in Northwest China under global warming.

  1. Research on Fertilizer Effects on Confectionary Sunflower in Northwest Hebei of China%冀西北食用向日葵肥料效应

    Institute of Scientific and Technical Information of China (English)

    杨素梅; 白苇; 田国联; 杨德智; 庞荣

    2012-01-01

    [Objective] The aim was to study the fertilizer effects on confectionary sunflower in northwest Hebei of China. [Method] Fine excellent varieties were sampled to carry out a '3414' teat to study different N,P and K fertilization levels,so as to explore the optimum fertilization benefit and optimum fertilization combination of the new varieties. [ Result] K fertilizer had the largest effect on the yield of confectionary sunflower. The maximum yielding fertilization combination of conventional varieties was 71.7 kg/hm2 N,48.3 kg/hm2 P2OS and 68.4 kg/hm2,K20, under which the yield was 3 052.5 kg/hm2. The best fertilization combination for highest economic benefits was 67. 2 kg/hm2 N,50. 1 kg/hm2 P2O5 and 68.3 kg/hm2 K2O,under which the yield was 2 909.7 kg/hm2.The maximum yielding fertilization combination of hybrid varieties was 65.1 kg/hm2 N,66.5 kg/hm2 P2O5 and 154.4 kg/hm2 K2O, under which the yield was 3 302.4 kg/hm2. The best fertilization combination for highest economic benefits was 72.8 kg/hm2 N,57.8 kg/hm2 P2O5 and 138.7 kg/hm2 K2O,under which the yield was3 291.3 kg/hm2. [Conclu-sion] The research provides a scientific basis for the promotion and cultivation technology of the new varieties.%[目的]研究冀西北食用向日葵的肥料效应.[方法]以近年筛选出的优良品种为供试品种,采用“3414”试验设计方案,对新品种进行不同N、P、K施肥水平的研究,以摸索新品种的最佳施肥效益、最佳施肥组合.[结果]钾肥对食用向日葵的产量影响较大.常规品种最高产量的施肥组合为N 71.7 kg/hm2、P2O5 48.3 kg/hm2、K2O 68.4 kg/hm2,此时产量达3 052.5 kg/hm2;最佳经济效益施肥组合为N67.2 kg/hm2、P2O5 50.1kg/hm2、K2O 68.3 kg/hm2,此时产量达2 909.7 kg/hm2.杂交品种最高产量的施肥组合为N 65.1 kg/hm2 、P2O566.5 kg/hm2、K2O 154.4 kg/hm2,此时产量达3 302.4 kg/hm2;最佳经济效益施肥组合为N 72.8 kg/hm2、P2O5 57.8 kg/hm2、K2O 138.8kg/hm2,此时产量达3 291

  2. Influence research on spring vegetation of Eurasia to summer drought- wetness over the northwest China%近半个世纪中国西北干湿演变及持续性特征分析

    Institute of Scientific and Technical Information of China (English)

    杨金虎; 江志红; 刘晓芸; 岳平

    2012-01-01

    利用1960-2007年中国西北地区248个气象台站的逐日降水、温度资料,通过降水和潜在蒸发均一化干湿指数,从年际演变、季节内变化以及持续性特征等方面较系统地揭示了近半个世纪来西北地区的区域性干湿演变事实,结果表明:在温度与降水双重因子驱动下西北地区的干湿演变特征同降水单一要素驱动下的干旱特征存在明显的差异,说明气候变暖对西北干旱化趋势的贡献程度比较显著;自20世纪90年代后期以来,西北各分区每年异常干旱月份发生概率呈增多趋势,而异常湿润月份发生概率除了北疆地区外,其它分区近10a异常偏少,这种现象在西北东南部表现得尤为突出。从四季干湿变化来看,冬季表现为湿润化趋势,而春、夏、秋三季呈现出了干旱化趋势。另外西北东南部、青海高原东侧以及南疆地区自20世纪90年代以来,很少出现过持续性湿润事件,而持续性干旱事件却明显多于90年代以前,而且持续性干旱的最长持续时间长,强度大,北疆地区和青海高原48a来持续性干湿事件发生频次、强度以及持续时间没有明显的趋势变化,而青海高原地区相比其它区域持续性干湿事件偏少,强度偏弱,最长持续时间也偏短。%Using temperature and precipitation data of 248 stations in Northwest China, from interannual change, in- terseasonal variability and durability characteristic posted regional drought and wetness evolvement over Northwest China in recent half century by homogenized drought - wetness index of precipitation and evaporation. The result showed that drought -wetness evolvement characteristic exist clear difference between driven by temperature and precipitation and driven by precipitation, this illuminated that contribution of climate warming to drought trend of Northwest China is marked. 'Since 1990 anaphase probability of abnormal

  3. 新疆与西北主网联网第二通道工程系统调试%System Commissioning for the Second Transmission Channel Project Interconnecting Xinjiang Grid With Northwest China Main Grid

    Institute of Scientific and Technical Information of China (English)

    郑彬; 杨大业; 王康平; 杨超; 印永华; 班连庚; 张健; 张振宇; 周佩朋; 罗煦之; 牛拴保; 何凤军

    2014-01-01

    ABSTRACT:The second 750 kV transmission channel project interconnecting Xinjiang Grid with northwest China main grid is one of the key construction projects of State Grid Corporation of China during China’s 12th Five Year Plan. This project, which relates to seven 750 kV substations and twelve 750 kV transmission lines, is an important constituent of 750 kV main network frame of Northwest China power grid and is also an important outward transmission channel of power generated by thermal plants, wind farms and photovoltaic generation stations located in Xinjiang and Northwest China. Through the implementation of this project, a new type of power electronic equipment group for flexible AC transmissions system (FACTS) composed of 750 kV bus-type magnetic-controlled shunt reactor, 750 kV line-type thyristor-controlled shut reactor, 66 kV high-capacity SVC and so on is formed and is the first FACTS equipment group in the world. The research on the system commissioning for this project solves such technical difficulties as the starting-up and voltage control strategy of new equipment located in long-distance weak power grid, the security pre-control of DC transmission system from Qaidam to Lhasa and new energy resources, systematic commissioning of new-type of FACTS equipment and multi-objective security control strategy for grid frame and so on, thus the system commissioning and implementation can be successfully completed. In this paper, the general situation of system commissioning for this project, the research on the system commissioning and the determination of commissioning scheme, main results of on-site commissioning are presented, and these contents are available for reference to putting this project into operation and for the construction of follow-up projects.%新疆与西北主网联网750 kV第二通道工程是国家电网公司“十二五”规划重点建设项目之一,涉及7站12线,是我国西北750 kV主网架的重要组成部分,也是

  4. Evolution Characteristics of the Extreme High Temperature Event in Northwest China from 1961 to 2009%中国西北地区1961—2009年极端高温事件的演变特征

    Institute of Scientific and Technical Information of China (English)

    陈少勇; 王劲松; 郭俊庭; 芦旭东

    2012-01-01

    利用中国西北地区135个测站1961—2009年历年逐日地面最高气温和NCEP/NCAR资料,采用线性趋势分析、Mann-Kendall、子波分析、合成分析等方法,分析了近49 a西北地区高温事件的演变特征。结果表明:西北地区极端高温的高值区在新疆大部分地区、河西走廊西部、甘肃中北部、陇东南、宁夏北部和陕西,这些地方的高温阈值在30℃以上;区域年极端高温频率以1.8 d/10 a的速率显著增多,1970年代中期高温日数发生由少至多的转型,1994年有突变,高温频数有显著的3-5 a周期,目前仍处于高温频发阶段;极端最高气温介于22.5-47.8℃之间,最大值出现在吐鲁番盆地。4—10月皆可出现高温,但主要出现在6—8月,其中7月最多。6月高温频率增加最显著,其他月份增加不明显;高温越强,持续日数越长,高温频发的时段也是高温最强的时段。气候变暖导致极端高温事件增多,强度增强。从大气环流合成分析表明,乌山脊、巴尔喀什湖低槽和蒙古脊中高层位置稳定,大气为准正压状态,西北地区在蒙古高脊控制下,有利于形成大范围持续性高温天气。%Using over years daily surface extreme air temperature and NCEP/NCAR data of 135 meteorological observation stations in Northwest China from 1961 to 2009, and adopting the meth- ods of linear regression analysis, Mann-Kendall, moving t-examination, wavelet analysis, power spectrum and composite analysis, we analyzed the evolution characteristics of high temperature e- vent in recent 49 years of Northwest China. The results show that spatial distribution of the ex- treme high temperature in Northwest China presents high value in the western and eastern parts, and low value in the central part. The main areas with extreme high temperature value are located in most part of Xinjiang, the western Hexi Corridor, the central and northern Gansu, southeastern Gansu, northern Ningxia and Shaanxi

  5. 气候变化对中国西北地区山区融雪径流的影响%Impact of Climate Change on Snowmelt Runoff in the Mountainous Regions of Northwest China

    Institute of Scientific and Technical Information of China (English)

    王建; 沈永平; 鲁安新; 王丽红; 史正涛

    2001-01-01

    选择祁连山黑河流域作为中国西北地区山区积雪流域的典型代表,分析了1956-1995年40 a以来气候、积雪变化的状况和特点以及春季融雪径流的波动趋势.利用融雪径流模型(Snowmelt Run-off Model-SRM)和卫星遥感数据模拟气温上升框架下的融雪径流变化情势.结果表明:中国西北地区山区的气候变化主要表现在年平均气温的缓慢上升而降水基本平稳,年内气温的上升幅度以1~2月份比较强烈,而3~6月融雪期的气温并没有大的变化,导致融雪期在时间尺度上的扩大,融雪径流呈慢增加趋势且受径流周期变化控制,融雪径流峰值在时间上前移.%Snow cover is an indicator for global warming. Climate change influences the distribution of glaciers and snow. Thus, air temperature rising results in changing of distribution of seasonal snow cover and regime of snowmelt runoff in Northwest China. Heihe Basin is a typical snow cover region with an area of 10 009 km2 in Northwest China, where snowmelt runoff is the main supply for water resources. It is found that an impact of climate change on snowmelt runoff in mountainous regions is clear in the basin. So in this paper, the Heihe Basin was sampled to analysis the impact in mountainous regions of Northwest China. The impact of snowmelt runoff was simulated by using Snowmelt Runoff Model SRM and satellite remote sensing data under air temperature rising. By analyzing the climatic and hydrological data sets derived from 46 observation stations for 40 years(1956-1995), an air temperature rising trend since 1956 is seen, together with a stable precipitation. The annual mean air temperature has increased about 0. 7~ 1.4 ℃. Temperature mainly rises in January and February, but less rises in the spring. Meanwhile, in the test area, variation in rainfall and snowfall has a small effect. When air temperature increasing in winter is the main variation of climate change

  6. Estimation and spatial-temporal characteristics of carbon sink in the arid region of northwest China%中国西北干旱区植被碳汇估算及其时空格局

    Institute of Scientific and Technical Information of China (English)

    潘竟虎; 文岩

    2015-01-01

    Global warming caused by greenhouse gas emissions has had a profound impact on human survival and development. Consequently, this phenomenon has received widespread attention from the international community. Vegetation can absorb greenhouse gases CO2 , and has a huge carbon sink function, so it has an irreplaceable role in slowing global warming. The carbon sink capacity of vegetation has a significant impact on regional and global climate change. Carbon emissions are undoubtedly enormous in the mid and high latitudes of the Northern Hemisphere, so studies on terrestrial ecosystem carbon dynamics and spatial patterns in the arid region of northwest China may provide an accurate assessment how China contributes towards mitigating global climate change and CO2 emission reduction. The net primary productivity (NPP) and heterotrophic respiration (RH) in the arid region of northwest China were calculated by using MODIS images, meteorological data, and a vegetation type map, in combination with an improved CASA model and soil microbial respiration model. The NPP and RH were then used to estimate net ecosystem productivity (NEP) and vegetation carbon sink from 2001 to 2012. Spatial-temporal characteristics and the reasons for NPP and carbon sink variation in the arid region of northwest China were analyzed. The results show that research methods used in this paper were able to quickly extract ecosystem net primary productivity and carbon sink for the northwest arid region. The methods used are efficient, convenient, and practical for large scale carbon balance and carbon cycling studies in this region. Comparison indicated small gaps between simulated and measured site values. The overall difference in the spatial distribution between simulated values and MODIS NPP products is also small, and the volatility of the analog value is less than the value of MODIS NPP products. NPP in the study area showed strong seasonal variation. The maximal NPP value was obtained in July

  7. 基于LM-BP神经网络的西北地区太阳辐射时空变化研究%Spatial and Temporal Changes in Solar Radiation of Northwest China Based LM-BP Neural Network

    Institute of Scientific and Technical Information of China (English)

    李净; 冯姣姣; 王卫东; 张福存

    2016-01-01

    定量模拟太阳辐射对认识西北地区气候变化至关重要,但西北地区辐射站点稀少,而气象站点较多,利用众多的气象站点观测值模拟太阳辐射是获得太阳辐射数据很好的方法之一.利用LM(Levenberg-Marquardt)算法对普通的BP神经网络进行优化(优化后的BP神经网络简称LM-BP神经网络)模拟太阳辐射,通过与传统气候模型模拟的太阳辐射结果对比发现,LM-BP神经网络模型的模拟精度最高,模拟值与实测值的拟合程度明显优于H-S模型和A-P模型.由此利用西北地区159个气象站点的气象数据和LM-BP神经网络模型模拟了1990~2012年这些气象站点的太阳总辐射月总量,将LM-BP神经网络模拟的气象站点的太阳辐射和25个辐射观测站的实测太阳辐射数据相结合,通过空间插值得到了西北地区太阳总辐射的空间分布,并分析了其时空分布及变化特征.研究结果发现西北地区1990~2012年的年均总辐射月总量变化为262~643 MJ/m2,呈现"中间高,两端低"的空间分布特征.LM-BP神经网络模型的模拟精度高,是一种很有发展前景的辐射模拟方法,可将其应用在无辐射观测地区的太阳辐射模拟中.%Solar radiation data can be used to simulate surface dynamic and thermal process. Solar radiation da-ta is the important input parameter of the models in ecology, hydrology, crop, solar radiation transmission, global circulation and so on. Quantitative simulation of solar radiation is important for understanding climate change in Northwest China. However, the solar radiation stations are sparse in Northwest China, so using small amount of radiation site data interpolating or extrapolating is difficult to obtain the spatial distribution of solar radiation data. There are more many weather stations in Northwest China, so it is one of the best methods to simulate the solar radiation by using a large number of meteorological observations. In this article, the LM

  8. Climatic Variation Characteristics and Influencing Factors of the Last Frost Date in Northwest China%西北地区晚霜冻结束日的气候变化特征及其影响因子

    Institute of Scientific and Technical Information of China (English)

    陈少勇; 夏权; 王劲松; 楼望萍

    2013-01-01

    利用西北地区135个测站,1961-2009年历年逐日地面最低气温和NCEP/NCAR资料,采用线性趋势分析、M-K检验、子波分析、功率谱和合成分析等方法,对近49a西北地区晚霜冻的气候变化特征进行研究.结果表明,研究区晚霜冻结束日期具有较大的空间差异,青海高原晚霜冻结束最晚,其次是北疆—河西走廊—宁夏,陇东—陕北,结束最早区为南疆和陇南—陕南.全区平均以1.9d/10a的速率提前,其中45%的站点显著提前(P<0.05),提前最大的地区在青海西北部—南疆东部,达5~8d/10a.20世纪90年代中期以后,西北地区晚霜冻结束早且年际变化小,1997年有明显的突变现象,近49a来晚霜冻有显著的2.4a和2.7a周期.表明在全球变暖背景下,西北地区晚霜冻的结束逐年提前,但近10a呈推迟趋势的站有所增多;影响西北地区晚霜冻的环流特征量主要有北非副高和极涡,与北非副高呈负相关,与极涡呈正相关.近10a晚霜冻结束偏迟的原因可能与极涡面积增大和北非副高面积减小有关;5月500hPa高度场合成分析表明,晚霜冻结束偏早年,亚洲北部盛行纬向环流,东亚大槽浅,西北地区受蒙古高压脊控制,不利于降温天气出现;晚霜冻偏迟年,亚洲北部盛行径向环流,西北地区上空不断有来自西北欧滑下的冷空气,易形成强降温天气.%Based on daily surface minimum air temperature data of 135 observational stations from 1961 to 2009 in Northwest China and NCEP/NCAR reanalysis data, authors analyzed the climatic variation characteristics of the last frost date by using the methods linear trend analysis, Mann - Kendall, Moving T-examination, Wavelet analysis, power spectrum and composite analysis methods. The results showed that there were large spatial difference of last frost end date in Northwest China, it was impacted by altitude that the cold period were long, so the area which last frost end latest was

  9. Analysis on Market Prospect of Potato Export to Central Asian Countries in Northwest Region of China%西北地区马铃薯出口中亚国家的市场前景分析

    Institute of Scientific and Technical Information of China (English)

    刘俊霞; 侯军岐

    2016-01-01

    西北地区是我国马铃薯的主产区,马铃薯产业的发展对地区经济及农民增收具有重要意义。中亚国家与我国西北地区毗邻,被称为“第二面包”的马铃薯在中亚国家有较大市场需求,发展潜力巨大。“一带一路”战略为西北地区马铃薯出口中亚国家搭建了较好的平台,西北地区可利用其先天性的地理位置优势、出口成本优势和技术优势等向中亚国家出口马铃薯产品。除了稳定传统鲜薯产品出口优势之外,西北地区还应通过境外投资、技术援助等方式带动马铃薯加工品、种薯及马铃薯附加产品的出口。%The Northwest region is the main producing area of potatoes in China.The potato industry has great significance to local economy and farmers’income.Central Asia countries are closed to this area,and have a large demand on potatoes which are called “the second bread”in these countries.And the potato industry has great mar-ket potential.The “Belt and Road”strategy has built a good platform to export potatoes from the Northwest re-gion of China to Central Asian countries.The region can take the advantage of its congenital geographical location, the low export costs and the technology advantages to export potatoes.Apart from maintaining the traditional ad-vantages,the region should also exploit some other ways such as overseas investment and technical assistance to stimulate the export of processed goods,seeds and augmented products of potatoes.

  10. 西北五省(区)城市绿地果树应用现状及发展建议%Current Situation and Development Suggestions for Application of Fruit Trees in Urban Landscape in 5 Provinces in Northwest China

    Institute of Scientific and Technical Information of China (English)

    杜晓丽

    2015-01-01

    分析了果树在西北地区城市绿地中应用种类、配置形式、景观效果,探讨了果树在城市绿地景观中独特作用.%The application species, configuration and landscape effect of fruit trees in northwest China are analyzed and some suggestions for development of fruit trees in urban landscape are put forward.

  11. 阿尔金山国家级自然保护区食肉鸟兽调查%Survey on Carnivore Birds and Mammals in Altun Mountain National Natural Reserve

    Institute of Scientific and Technical Information of China (English)

    李叶; 张翔; 时磊

    2012-01-01

    2011-2012年,对阿尔金山国家级自然保护区的鼠类天敌——食肉鸟兽开展专项调查.通过调查,初步查明了保护区内共分布有鼠类天敌27种,分属2纲3目7科17属,其中有国家一级保护动物5种,二级保护动物17种.赤狐为保护区首次记录物种.对主要天敌的种类、分布、食性和活动规律,以及对高原鼠兔防治的潜在作用进行了初步分析.藏狐和大鵟可以作为进一步开展天敌防治鼠害工作的目标物种.%A special investigation on carnivorous mammals and birds was carried out in the Altun Mountain National Nature Reserve in 2011-2012. Research found out total 27 kinds of predators on rodent pests belonging to 2 classes,3 orders,7 families,and 17 genera distributing in the protected areas. Among them there are 5 kinds of national first class protection animal and 17 kinds of national second class protection animal. The red fox(Vulpes vuLpes)was first recorded from this region. The first analysis was carried out on varieties,distribution,feeding habits and the patterns of the main natural enemies and the potential role in controlling plateau pika (Ochotona curzoniae) . Tibetan fox and Buzzard can be used as target species for a further natural enemies controlling pika project.

  12. 西北地区生态环境建设中水资源可持续开发与管理的认识%KNOWLEDGE ON SUSTAINABLE EXPLOIT AND MANAGEMENT OF WATE RRESOURCES CONCERNING ECOLOGICAL RESTORATION IN NORTHWEST CHINA

    Institute of Scientific and Technical Information of China (English)

    邓林

    2001-01-01

    西北地区水资源短缺,生态环境相当脆弱。随着西北地区大规模生态环境建设的实施,原来水资源的供需矛盾更为明显,处理好西北地区有限水资源中经济用水和生态用水的比例关系具有重要的意义。就西北地区的生态环境建设中水资源可持续开发和利用提出几点认识。%There is a shortage of water resources in Northwest China where the ecological environment is very brittle. With the implementation of ecological restoration on large scale in the area, the contradiction between water supply and need becomes more pronounced. So it is very important to make use of limited water resources in a reasonable proportion of water use in ecological restoration and in economic activities in Northwest China. The paper brings forward some knowledge on sustainable exploit and management of water resources concerning ecological restoration in Northwest China.

  13. OMI-measured SO2 in a large-scale national energy industrial base and its effect on the capital city of Xinjiang, Northwest China

    Science.gov (United States)

    Wang, Jinxiang; Mo, Jingyue; Li, Jixiang; Ling, Zaili; Huang, Tao; Zhao, Yuan; Zhang, Xiaodong; Mao, Xiaoxuan; Gao, Hong; Shen, Yanjie; Ma, Jianmin

    2017-10-01

    Although considerable efforts have been made to improve air quality in Urumqi city, the capital of Xinjiang-Uyghur Autonomous Region in northwestern China and one of the ten cities with worst air quality in China, this city is still experiencing heavy air pollution during the wintertime. The satellite remote sensing of air quality using Ozone Monitoring Instrument (OMI) measured data discerned an increasing trend of the planetary boundary layer (PBL) columns of sulfur dioxide (SO2) in Midong national petrochemical and coal chemical industry base from 2005 to 2016, located in the northeast of Urumqi. The increasing trend of OMI columnar SO2 in this area is in contrast to the widespread decreases in SO2 emissions in eastern and southern China. This is mainly induced by rapid development in the energy industry in this region over the past decade under the national strategy for energy industry expansion and relocation to northwestern China. We observed a significant correlation of OMI columnar SO2 between this energy industrial base and Urumqi city in winter (R = 0.504, p < 0.005), suggesting that SO2 emitted from heavily contaminated energy industrial base exacerbated the air quality in Urumqi city. The Weather Research and Forecasting Chemistry (WRF-Chem) modeling confirms that the occurrence of heavy smog in this capital city during the wintertime was attributed primarily to strong emissions of air contaminants from the energy industrial base under favorable winds. A numerical case study with and without taking the Midong Industry Base into consideration revealed that this industry base contributed 38% to the SO2 level in Urumqi city, offsetting the considerable efforts made by the local government to improve air quality in this city.

  14. PACIFIC NORTHWEST CYBER SUMMIT

    Energy Technology Data Exchange (ETDEWEB)

    Lesperance, Ann M.; Matlock, Gordon W.; Becker-Dippmann, Angela S.; Smith, Karen S.

    2013-08-07

    On March 26, 2013, the Snohomish County Public Utility District (PUD) and the U.S. Department of Energy’s (DOE’s) Pacific Northwest National Laboratory (PNNL) jointly hosted the Pacific Northwest Cyber Summit with the DOE’s Office of Electricity Delivery and Energy Reliability, the White House, Washington State congressional delegation, Washington State National Guard, and regional energy companies.

  15. Evaluative Characteristic of Extreme Minimum Temperature of Northwest China in Recent 49 Years%近49年中国西北地区极端低温事件的演变特征

    Institute of Scientific and Technical Information of China (English)

    陈少勇; 王劲松; 任燕; 乔立

    2011-01-01

    The low temperature events were analyzed based on the NCEP/NCAR data and the daily minimum temperature observation data from 135 meteorological stations in the Northwest China during 1961-2009,using the methods of linear regression analysis,Mann-Kendall,running T-test,wavelet analysis,power spectrum and composite analysis.The results show that:(1) The spatial distribution of the extreme minimum temperature in Northwest China presents the distributed tendencies of two high and low interactions.The areas with minimum temperature value are located in northern Xinjiang and Qinghai Plateau.And the threshold value of extreme minimum temperature in these places are below-20 ℃;(2) The frequency of annual extreme minimum temperature has obviously reducing at a rate of 3.7 d·(10 a)-1,majority places remarkably reduced at a rate of 3~5 d·(10 a)-1.There is an abrupt change in 1985,the minimum temperature frequency has the remarkable 3 year periods.(3) The values of extreme minimum temperature are between-49.8 to-8.6 ℃,the maximum value appears in Fuyun of Xinjiang.There is a same geographic distribution between minimum temperature intensity and extreme minimum temperature. The intenser the extreme minimum temperature is,the longer the day number of duration is. The phase of frequently occurring of minimum temperature is also the phase of the strongest minimum temperature.The global warming causes the extreme minimum temperature events reducing and intensity weakening.(4) From the circulation characteristic quantity analysis, the extreme minimum temperature in Xinjiang related with zonal circulation,polar vortex characteristic quantity and Atlantic-Europe circulation,but the extreme minimum temperature in other places related with subtropical high and QinghaiXizang Plateau height field.The composited analysis indicated that the polar vorticity center is located the Eastern Hemisphere.The Arctic region is the positive anomalous.The middle latitude

  16. 一个乡村治病过程的人类学解读%Anthropological Interpretation of the Health-seeking Process of a Village Woman in Northwest China

    Institute of Scientific and Technical Information of China (English)

    张有春

    2011-01-01

    This paper is a case study of the health-seeking process of a woman in a village of Northwest China.It explores into people's health-seeking behavior in the context of medical pluralism and the relationship between various medical systems such as between%以河西走廊一个乡村妇女治病过程为个案,探讨了多元医学语境中人们的求医行为,以及西医与仪式治疗、中医与西医等不同医学在实践层面的关系。在医学信息的传播与交流日趋频繁、医学多元成为一种社会现实的语境中,人类学需要探讨多元医学语境中人们的求医行为,并在动态中把握不同医学之间的关系。

  17. [Effect of long-term shallow tillage and straw returning on soil potassium content and stratification ratio in winter wheat/summer maize rotation system in Guanzhong Plain, Northwest China].

    Science.gov (United States)

    Shi, Jiang-lan; Li, Xiu-shuang; Wang, Shu-juan; Li, Shuo; Li, You-bing; Tian, Xiao-hong

    2015-11-01

    Soil stratified sampling method and potassium chemical fractionation analysis were used to investigate effects of long-term shallow tillage and straw returning on soil K contents and stratification ratios in winter wheat/summer maize rotation system in Guanzhong Plain of Northwest China. The results showed that after 13-year continuous shallow tillage and straw returning, surface accumulation and stratification effect obviously occurred for soil available K (SAK) and non-exchangeable K (NEK), which was particularly remarkable for SAK and its fractions. Serious depletion of SAK occurred in 15-30 cm soil layer, and the SAK value was lower than the critical value of soil potassium deficiency. Meanwhile, significant differences were found between SR1 and SR2 values of SAK and its fractions, SR was obtained by values of topsoil layer (0-5 cm) divided by corresponding values of lower soil layers (5-15 cm layer, SR1, or 15-30 cm layer, SR2). However, no significant difference was observed between SR values of NEK and mineral K. In conclusion, returning of all straw over 10 years in the winter wheat/summer maize rotation system contributed greatly to maintaining soil K pool balance, while special attention should be paid to the negative effects of surface accumulation and stratification of SAK on soil K fertility.

  18. On the Modeling and Emulation of the Microclimate of Sunlight Greenhouse in the Northwest China%西北日光温室小气候建模与仿真

    Institute of Scientific and Technical Information of China (English)

    田亚立; 杨泽林; 李相白

    2011-01-01

    The microclimate of greenhouse was a nonstationary, nonliner dynamic environment with strong coupling and great lag. The model and emulation were established for the greenhouse microclimate in order to build a sound supervisory and control system of the greenhouse. Based on the characteristics of microclimate of greenhouse, and the specific macroclimate in the summer of northwest china, the temperature and humidity models were set up by the new international method of heat banlance steady state equation. Through the analysis and emulation experiments, the effects were basically conform what were supposed.%针对温室小气候的基本特点,结合国际较新的热平衡稳定状态方法,根据西北地区夏季的温室具体情况,建立了温室的温度、湿度模型.通过对模型的分析和仿真试验,取得了较好的效果.

  19. 西北戈壁滩地区冬期混凝土涵节预制质量监控%On quality inspection measures for concrete culvert section prefabricating during winter period gibi deserts of Northwest in China

    Institute of Scientific and Technical Information of China (English)

    张选锋

    2014-01-01

    From the internal and external factors of concrete,the paper analyzes the reasons for the quality common diseases of the concrete cul-vert section prefabricating during winter period gibi deserts of Northwest in China,mainly explores the construction control measures,and illus-trates the construction difficulties and main points,construction organization and arrangement,and factual measures for the culvert prefabricating of winter period,so as to provide some scientific reference for construction.%从混凝土的内在因素与外界因素两个角度分析了西北戈壁滩地区冬期混凝土涵节预制的质量通病原因,着重对施工控制措施进行了探讨,阐述了冬期涵节预制的施工重难点、施工组织安排及具体措施,为顺利施工提供了科学依据。

  20. An inverse association of body mass index and prostate-specific antigen in northwest men of China: a population-based analysis

    OpenAIRE

    Zhang, Jianqin; Sheng, Binwu; Ma, Mao; Nan, Xunyi

    2015-01-01

    Objectives: To examine the relationship between body mass index (BMI) and prostate-specific antigen (PSA) in Chinese men and to investigate whether this relationship was independent of other factors. Methods: Cross-sectional analysis was in men aged 19 to 82 years old (N=12,964) who without prostate cancer and had health examination between 2008 and 2013 in a clinical center in Xi’an, China. Obesity and overweight were classified according to the WHO criterion. Mean PSA level was calculated b...

  1. [PS II photochemical efficiency in flag leaf of wheat varieties and its adaptation to strong sun- light intensity on farmland of Xiangride in Qinghai Province, Northwest China].

    Science.gov (United States)

    Shi, Sheng-Bo; Chen, Wen-Jie; Shi, Rui; Li, Miao; Zhang, Huai-Gang; Sun, Ya-Nan

    2014-09-01

    Taking four wheat varieties developed by Northwest Institute of Plateau Biology, Chinese Academy of Sciences, as test materials, with the measurement of content of photosynthetic pigments, leaf area, fresh and dry mass of flag leaf, the PS II photochemistry efficiency of abaxial and adaxial surface of flag leaf and its adaptation to strong solar radiation during the period of heading stage in Xiangride region were investigated with the pulse-modulated in-vivo chlorophyll fluorescence technique. The results indicated that flag leaf angle mainly grew in horizontal state in Gaoyuan 314, Gaoyuan 363 and Gaoyuan 584, and mainly in vertical state in Gaoyuan 913 because of its smaller leaf area and larger width. Photosynthetic pigments were different among the 4 varieties, and positively correlated with intrinsic PS II photochemistry efficiencies (Fv/Fm). In clear days, especially at noon, the photosynthetic photoinhibition was more serious in abaxial surface of flag leaf due to directly facing the solar radiation, but it could recover after reduction of sunlight intensity in the afternoon, which meant that no inactive damage happened in PS II reaction centers. There were significant differences of PS II actual and maximum photochemical efficiencies at the actinic light intensity (ΦPS II and Fv'/Fm') between abaxial and adaxial surface, and their relative variation trends were on the contrary. The photochemical and non-photochemical quenching coefficients (qP and NPQ) had a similar tendency in both abaxial and adaxial surfaces. Although ΦPS II and qP were lower in adaxial surface of flag leaf, the Fv'/Fm' was significantly higher, which indicated that the potential PS II capture efficiency of excited energy was higher. The results demonstrated that process of photochemical and non-photochemical quenching could effectively dissipate excited energy caused by strong solar radiation, and there were higher adaptation capacities in wheat varieties natively cultivated in

  2. Element Geochemistry and Petrogenesis of High—K Potassic Dike Rocks in Two Types of Gold Ore Fields in Northwest Jiaodong,Shandong,China

    Institute of Scientific and Technical Information of China (English)

    孙景贵; 叶瑛; 等

    2000-01-01

    This paper deals with the high-K,potassic dike rocks in two types of gold ore fields at Linglong and Dayigezhuang,Northwest Jiaodong.The rocks can be divided into three types.i.e.,(1) lamprophyre,(2) andesite porphyrite,and (3) dacite porphyrite,based on their geological occurrence and space-time relationship with gold mineralization.These rocks were the products of early,synchronous and late mineralization.respectively,Element geochemistry shows that variations in chemical composition of major oxides follow the general rules of magmatic fractional crystallization.The fractional crystallization of mineral phases of augite in the early stage(namely in the lamprophyre stage)and hornblende and plagioclase in the late stge(namely from the andesite-porphyrite to dacite porphyrite stage)controlled the magma evolution.The rocks are enriched in alkili and have higher K2O and lower TiO2 contents,as well as strongly enriched in large ion lithophile elements such as Ba,Sr and Rb,and LREE but strongly depleted in transition elements such as Cr and Ni,Rb is depleted relative to Sr and Ba,and Rb/Sr ratios are low.Volatile constituents are abundant.These characteristics indicate that the initial magma originated from the metamorphic subduction ocean-crust that had been intensively contaminated by crustal materials,and retrogressive metamorphism is characterized by low-degree partial melting during back-arc spreading,Varying degrees of partial melting and different emplacement enviornments may be the main causes for the evolution of the rocks and mineralization in different degrees in the two gold ore fields at Linglong and Dayigezhuang,Shandong.

  3. Cenozoic Uplift and Denudation of the EW-trending Range of Northern Altun Mountains:Evidence from Apatite Fission Track Data%阿尔金北缘EW向山脉新生代隆升剥露的裂变径迹证据

    Institute of Scientific and Technical Information of China (English)

    孙岳; 陈正乐; 陈柏林; 韩凤彬; 周永贵; 郝瑞祥; 李松彬

    2014-01-01

    This paper mainly presents analytical results of apatite fission-track ages to constrain the uplifting characteristics of EW-trending range of Northern Altun Mountains. 22 rock mass samples were collected from Zhuoerbulake, Dapinggou, and Kaladawan in EW-trending mountain range of Northern Altun Mountains. Fission-track ages for these samples range from (62.6±3.5) to (28.3±1.7) Ma with mean track lengths varying from (13.25±0.15) to (14.29±0.1)μm. According to track lengths and measured age data, the authors carried out the inversion simulation on temperature and age of apatite. The results show a specific regularity of the uplifting of Northern Altun Mountains. In the SN direction, the fission-track ages display a uplifting trend from south to north. In the EW direction, the ages of Dapinggou area in the middle mountains were older than those of other areas and confined to Paleocene and Eocene, and imply an uplifting trend from the middle outwards. The similar thermal history simulation lines of all samples and the single peak of track lengths are considered to have been caused by rapid uplifting during the Paleocene-Eocene (63~28 Ma) and steadiness during the Miocene and later periods in the Northern Altun Mountains. A comparative study of the uplifting and exhumation of the whole Altun area shows that the mountains uplifting and denudation of this region had both global and unique features in Cenozoic: the uplifting of the Altun Mountains had universality and regional features in Paleogene, but uplifting and exhumation existed in NEE-trending and NE-trending mountain ranges in Miocene and subsequent period. It is held that the rapid strike-slip Altun fault has had no influence on uplifting and denudation of EW-trending mountain ranges in Northern Altun Mountains since Miocene.%本文主要利用磷灰石裂变径迹测年技术探讨了阿尔金北缘EW向山脉隆升的时空差异特征。22个岩体分别采自阿尔金北缘EW向山体中的卓尔布

  4. Population genetic analysis of the GlobalFiler STR loci in 748 individuals from the Kazakh population of Xinjiang in northwest China.

    Science.gov (United States)

    Zhang, Honghua; Yang, Shuping; Guo, Wei; Ren, Bo; Pu, Liwen; Ma, Teng; Xia, Mingying; Jin, Li; Li, Liming; Li, Shilin

    2016-09-01

    The six-dye GlobalFiler™ Express PCR amplification kit incorporates 21 commonly used autosomal short tandem repeat (STR) loci and three gender determination loci. In this study, we analyzed the GlobalFiler STR loci on 748 unrelated individuals from a Chinese Kazakh population of Xinjiang, China. No significant deviations from Hardy-Weinberg equilibrium and linkage disequilibrium were observed within and between 21 autosomal STR loci. SE33 showed the greatest power of discrimination in Kazakh population. The combined power of discrimination of Kazakh was 99.999999999999999999999996797 %. No significant differences of allele frequencies were observed between Kazakh and Uyghur at all 15 tested STR loci, as well as Mongolian. Significant differences were only observed between Kazakh and the other Chinese populations at TH01. Multiple STR loci showed significant differences between Kazakh and Arab, as well as South Portuguese. The multidimensional scaling plot (MDS) plot and neighbor-joining tree also showed Kazakh is genetically close to Uyghur.

  5. PRELIMINARY SURVEY ON PENICILLIA AND THEIR TELEOMORPHS FROM NORTHWEST CHINA%中国西北地区青霉及其有性型初报

    Institute of Scientific and Technical Information of China (English)

    王龙; 孔华忠

    2002-01-01

    本文报道分离自中国西北地区-新疆、青海、甘肃和陕西的青霉菌Penicillium及其有性型正青霉Eupenicillium和篮状菌Talaromyces共47种,包括三个中国新记录种: 皮壳正青霉Eupenicillium crustaceum,真灰绿正青霉Eupenicillium euglaucum和西奈正青霉Penicillium sinaicum,并对此三个种作了描述并附线条图和子囊孢子的扫描电镜照片.%A checklist of 47 species of the genus Penicillium and its teleomorphs, Eupenicillium and Talaromyces, isolated from Xinjiang Uygur Autonomous Region, Qinghai, Gansu, and Shaanxi provinces, is provided in this paper. Among them, Eupenicillium crustaceum, E. euglaucum and E. sinaicum are first reported from China.

  6. Epidemiological Investigation on Acute Paraquat Poisoning of an Emergency Department in Northwest China Region%西北地区大型医院急诊科百草枯中毒流行病学特征

    Institute of Scientific and Technical Information of China (English)

    刘善收; 虎晓岷; 黄杨; 李俊杰; 尹文

    2014-01-01

    Objective To explore the epidemiological characteristics of paraquat poisoning in Northwest China re-gion, thus to provide scientific basis for optimized strategy of paraquat poisoning. Methods A retrospective observational study was carried out from August 2012 to December 2013 in an emergency department in Northwest China region. Clinical da-ta of 157 paraquat poisoned patients admitted into the emergency department was recorded. The age, gender, marriage, occu-pation, poisoning season, approach, toxic dose, hospital length of stay and outcome of paraquat poisoned patients were de-scribed and compared among different groups of toxic doses. And then, we analyzed the patient's treatment success rate ac-cording to the toxic dose. Results (1) Among 157 paraquat poisoned patients, 92 cases (58. 6%) were women. The mean age was (31. 5 ± 12. 8) years. 102 cases (65. 0%) were married. 110 cases (70. 1%) were farmers or students from peasant families. The main poisoning approach was oral poisoning (96. 8%). The average dose of paraquat poisoning was 37. 5 (20~100) ml. and 91 patients (58. 0%) were saved finally. (2) Summer and fall were the main onset seasons, which accounted for 73. 2% of the total poisoned patients and the patients from. 20 to 29 years old accounted for the largest poisoning popula-tion (25. 5%). Compared with the females, males accounted for 55. 3% of paraquat poisoning among 10 to 19 years old, de-creasing with age increasing. (3)The average dose of male paraquat poisoning patients was larger than that of females among 10 to 19 years old. However, the mean dose of female patients started to outpace male patients among 20 to 29 years old, in-creasing with age. On the contrary, the latter would decline with age. The mean dose of female married patients was signifi-cantly larger than that of the married male patients (Z=5. 54, P=0. 021). (4) The survival rates were significantly different among different groups of toxic dose (χ2 =78. 31, P<0. 001

  7. Sustainable management of river oases along the Tarim River (SuMaRiO) in Northwest China under conditions of climate change

    Science.gov (United States)

    Rumbaur, C.; Thevs, N.; Disse, M.; Ahlheim, M.; Brieden, A.; Cyffka, B.; Duethmann, D.; Feike, T.; Frör, O.; Gärtner, P.; Halik, Ü.; Hill, J.; Hinnenthal, M.; Keilholz, P.; Kleinschmit, B.; Krysanova, V.; Kuba, M.; Mader, S.; Menz, C.; Othmanli, H.; Pelz, S.; Schroeder, M.; Siew, T. F.; Stender, V.; Stahr, K.; Thomas, F. M.; Welp, M.; Wortmann, M.; Zhao, X.; Chen, X.; Jiang, T.; Luo, J.; Yimit, H.; Yu, R.; Zhang, X.; Zhao, C.

    2015-03-01

    The Tarim River basin, located in Xinjiang, NW China, is the largest endorheic river basin in China and one of the largest in all of Central Asia. Due to the extremely arid climate, with an annual precipitation of less than 100 mm, the water supply along the Aksu and Tarim rivers solely depends on river water. This is linked to anthropogenic activities (e.g., agriculture) and natural and semi-natural ecosystems as both compete for water. The ongoing increase in water consumption by agriculture and other human activities in this region has been enhancing the competition for water between human needs and nature. Against this background, 11 German and 6 Chinese universities and research institutes have formed the consortium SuMaRiO (Sustainable Management of River Oases along the Tarim River; http://www.sumario.de), which aims to create a holistic picture of the availability of water resources in the Tarim River basin and the impacts on anthropogenic activities and natural ecosystems caused by the water distribution within the Tarim River basin. On the basis of the results from field studies and modeling approaches as well as from suggestions by the relevant regional stakeholders, a decision support tool (DST) will be implemented that will then assist stakeholders in balancing the competition for water, acknowledging the major external effects of water allocation to agriculture and to natural ecosystems. This consortium was formed in 2011 and is funded by the German Federal Ministry of Education and Research. As the data collection phase was finished this year, the paper presented here brings together the results from the fields from the disciplines of climate modeling, cryology, hydrology, agricultural sciences, ecology, geoinformatics, and social sciences in order to present a comprehensive picture of the effects of different water availability schemes on anthropogenic activities and natural ecosystems along the Tarim River. The second objective is to present the

  8. Temporal and spatial variation of annual mean air temperature in arid and semiarid region in northwest China over a recent 46 year period

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    We analyzed the 1961-2006 mean surface air temperature data of 138 stations in China’s northwest arid and semi-arid areas(CNASA),to measure climate change in terms of annual mean air temperature changes.We used methods of linear regression analysis,multinomial fitting,Empirical Or-thogonal Function(EOF),Rotated Empirical Orthogonal Function(REOF),Mann-Kendall,Glide T-examination,wavelet analysis and power spectrum analysis.The results show that(1) the warming rate of the annual mean air temperature in CNASA was 0.35oC/10a during the 1961-2006 study period.Some places in the west part of Xinjiang and east part of the Qinghai plateau,which is impacted by the terrain of leeward slope,exhibit smaller increasing trends.However,the majority of region has shown distinct warming in line with general global warming;(2) The standard deviation of the annual mean temperature distribution is non-uniform.The south Xinjiang and east Qinghai-south Gansu areas show relatively small standard deviations,but the inter-annual variation in annual mean air temperature in the greater part of the region is high;(3) Inner Mongolia,Shaanxi,Gansu,Ningxia and Tarim Basin are the areas where the temperature changes are most sensitive to the environment.The degree of uniformity in annual mean air temperature increase is higher in the arid and semi-arid area.From the early 1970s,the trend in tempera-ture changed from a decrease to an increase,and there was a marked increase in mean temperature in 1986.After that mean temperature went through a period of rapid increase.The entire area’s 10 hottest years all occurred in or since the 1990s,and 90% of various sub-districts’ hottest years also occurred after 1990.The process of temperature change appears to have a roughly 5-year and a 10-year cycle;(4) An-nual mean air temperature variation has regional differences.In Inner Mongolia-Xinjiang and Shaanxi-Gansu-Ningxia-Qinghai areas,the temperature variation in their northern areas was very

  9. Middle-Upper Ordovician (Darriwilian-Early Katian) Positive Carbon Isotope Excursions in the Northern Tarim Basin, Northwest China:Implications for Stratigraphic Correlation and Paleoclimate

    Institute of Scientific and Technical Information of China (English)

    Cunge Liu; Guorong Li; Dawei Wang; Yongli Liu; Mingxia Luo; Xiaoming Shao

    2016-01-01

    ABSTRACT:Three positive carbon isotope excursions are reported from Middle–Upper Ordovician in Tahe oil-gas field, northern Tarim Basin. Based on conodont biostratigraphy, the Middle Darriwilian Isotope Carbon Excursion (MDICE) and the Guttenberg Carbon Isotope Excursion (GICE) are identified from Darriwilian to Early Katian by the aid of whole-rock carbon isotope data from two well cores. Positive excursion within conodont Pygodus anserinus zone is developed in Early Sandbian, and the fluctuation range is no less than MDICE. Because the range of this excursion in the generalized global carbon isotope curve is short, previous studies paid little attention to it, and named Early Sandbian Isotope Carbon Excursion (ESICE) in this paper. Furthermore, these positive excursions are not directly related to sea level fluctuations and the MDICE and GICE identified in northern Tarim can be globally correlated to that in southern China, North America, South America, and Europe. The Saergan Fm. source rocks of Middle-Upper Ordovician in Kalpin Dawangou outcrop are in accord with the geologic time of MDICE and ESICE, and GICE have strong ties to the source rock of Lianglitag Fm. in basin. Abundant organic carbon burial is an important factor in genesis of positive isotope carbon excursions. Positive oxygen isotope excursion, conodont fauna turnover, decreased conodont total diversity, and the change of sedimentary facies indicated that dramatic changes of paleoceanographic environment of Early-Middle Ordovician in Tarim Basin started from the end of Darriwillian, and an obvious icehouse climate of Late Ordovician occurred in ESICE.

  10. Testing the hypothesis of an ancient Roman soldier origin of the Liqian people in northwest China: a Y-chromosome perspective.

    Science.gov (United States)

    Zhou, Ruixia; An, Lizhe; Wang, Xunling; Shao, Wei; Lin, Gonghua; Yu, Weiping; Yi, Lin; Xu, Shijian; Xu, Jiujin; Xie, Xiaodong

    2007-01-01

    The Liqian people in north China are well known because of the controversial hypothesis of an ancient Roman mercenary origin. To test this hypothesis, 227 male individuals representing four Chinese populations were analyzed at 12 short tandem repeat (STR) loci and 12 single nucleotide polymorphisms (SNP). At the haplogroup levels, 77% Liqian Y chromosomes were restricted to East Asia. Principal component (PC) and multidimensional scaling (MDS) analysis suggests that the Liqians are closely related to Chinese populations, especially Han Chinese populations, whereas they greatly deviate from Central Asian and Western Eurasian populations. Further phylogenetic and admixture analysis confirmed that the Han Chinese contributed greatly to the Liqian gene pool. The Liqian and the Yugur people, regarded as kindred populations with common origins, present an underlying genetic difference in a median-joining network. Overall, a Roman mercenary origin could not be accepted as true according to paternal genetic variation, and the current Liqian population is more likely to be a subgroup of the Chinese majority Han.

  11. Evolution of the groundwater system under the impacts of human activities in middle reaches of Heihe River Basin (Northwest China) from 1985 to 2013

    Science.gov (United States)

    Mi, Lina; Xiao, Honglang; Zhang, Jianming; Yin, Zhenliang; Shen, Yongping

    2016-06-01

    Investigation of the evolution of the groundwater system and its mechanisms is critical to the sustainable management of water in river basins. Temporal and spatial distributions and characteristics of groundwater have undergone a tremendous change with the intensity of human activities in the middle reaches of the Heihe River Basin (HRB), the second largest arid inland river basin in northwestern China. Based on groundwater observation data, hydrogeological data, meteorological data and irrigation statistical data, combined with geostatistical analyses and groundwater storage estimation, the basin-scaled evolution of the groundwater levels and storage (from 1985 to 2013) were investigated. The results showed that the unbalanced allocation of water sources and expanded cropland by policy-based human activities resulted in the over-abstraction of groundwater, which induced a general decrease in the water table and groundwater storage. The groundwater level has generally fallen from 4.92 to 11.49 m from 1985 to 2013, especially in the upper and middle parts of the alluvial fan (zone I), and reached a maximum depth of 17.41 m. The total groundwater storage decreased by 177.52 × 108 m3; zone I accounted for about 94.7 % of the total decrease. The groundwater balance was disrupted and the groundwater system was in a severe negative balance; it was noted that the groundwater/surface-water interaction was also deeply affected. It is essential to develop a rational plan for integration and management of surface water and groundwater resources in the HRB.

  12. An inverse association of body mass index and prostate-specific antigen in northwest men of China: a population-based analysis.

    Science.gov (United States)

    Zhang, Jianqin; Sheng, Binwu; Ma, Mao; Nan, Xunyi

    2015-01-01

    To examine the relationship between body mass index (BMI) and prostate-specific antigen (PSA) in Chinese men and to investigate whether this relationship was independent of other factors. Cross-sectional analysis was in men aged 19 to 82 years old (N=12,964) who without prostate cancer and had health examination between 2008 and 2013 in a clinical center in Xi'an, China. Obesity and overweight were classified according to the WHO criterion. Mean PSA level was calculated by categories (normal weight, overweight, and obesity) and age group (≤ 40, 41-59, ≥ 60 years old). The association between BMI and PSA was examined using multivariate regression models and stratified by age. The crude prevalence was 38.42% for overweight and 3.47% for obesity in the study population. Mean PSA level increased with age at each BMI category. BMI was negatively associated with PSA level at each age group, independent of fasting plasma glucose (FPG) and prostate volume. Per unit increase in BMI was associated with a decrease of PSA by 0.03 (P=0.05), 0.11(P 60 years old, respectively. Our results indicate that a higher BMI is associated with a lower level of PSA in healthy Chinese men across all age group, independent of prostate volume and FPG. With the current obesity epidemic, individual's BMI should be considered when PSA test is used to screen or diagnose prostate cancer.

  13. Draft genome sequence of Halomonas lutea strain YIM 91125(T) (DSM 23508(T)) isolated from the alkaline Lake Ebinur in Northwest China.

    Science.gov (United States)

    Gao, Xiao-Yang; Zhi, Xiao-Yang; Li, Hong-Wei; Zhou, Yu; Lapidus, Alla; Han, James; Haynes, Matthew; Lobos, Elizabeth; Huntemann, Marcel; Pati, Amrita; Ivanova, Natalia N; Mavromatis, Konstantinos; Tindall, Brian J; Markowitz, Victor; Woyke, Tanja; Klenk, Hans-Peter; Kyrpides, Nikos C; Li, Wen-Jun

    2015-01-01

    Species of the genus Halomonas are halophilic and their flexible adaption to changes of salinity and temperature brings considerable potential biotechnology applications, such as degradation of organic pollutants and enzyme production. The type strain Halomonas lutea YIM 91125(T) was isolated from a hypersaline lake in China. The genome of strain YIM 91125(T) becomes the twelfth species sequenced in Halomonas, and the thirteenth species sequenced in Halomonadaceae. We described the features of H. lutea YIM 91125(T), together with the high quality draft genome sequence and annotation of its type strain. The 4,533,090 bp long genome of strain YIM 91125(T) with its 4,284 protein-coding and 84 RNA genes is a part of Genomic Encyclopedia of Type Strains, Phase I: the one thousand microbial genomes (KMG-I) project. From the viewpoint of comparative genomics, H. lutea has a larger genome size and more specific genes, which indicated acquisition of function bringing better adaption to its environment. DDH analysis demonstrated that H. lutea is a distinctive species, and halophilic features and nitrogen metabolism related genes were discovered in its genome.

  14. Spatial-temporal variability of soil water content in a cropland-shelterbelt-desert site in an arid inland river basin of Northwest China

    Science.gov (United States)

    Shen, Qin; Gao, Guangyao; Hu, Wei; Fu, Bojie

    2016-09-01

    Knowledge of the spatial-temporal variability of soil water content (SWC) is critical for understanding a range of hydrological processes. In this study, the spatial variance and temporal stability of SWC were investigated in a cropland-shelterbelt-desert site at the oasis-desert ecotone in the middle of the Heihe River Basin, China. The SWC was measured on 65 occasions to a depth of 2.8 m at 45 locations during two growing seasons from 2012 to 2013. The standard deviation of the SWC versus the mean SWC exhibited a convex upward relationship in the shelterbelt with the greatest spatial variation at the SWC of around 22.0%, whereas a linearly increasing relationship was observed for the cropland, desert, and land use pattern. The standard deviation of the relative difference was positively linearly correlated with the SWC (p management. The representative locations of each soil layer could be used to estimate the mean SWC well. The statistics of temporal stability of the SWC could be presented equally well with a low frequency of observation (30-day interval) as with a high frequency (5-day interval). Sampling frequency had little effect on the selection of the representative locations of the field mean SWC. This study provides useful information for designing the optimal strategy for sampling SWC at the oasis-desert ecotone in the arid inland river basin.

  15. 基于S PE I指数的西北地区春旱时空分布特征%Spatial and Temporal Distribution of Spring Drought in Northwest China Based on Standardized Precipitation Evapotranspiration Index

    Institute of Scientific and Technical Information of China (English)

    陈斐; 杨沈斌; 王春玲; 王润元; 王鹤龄; 齐月

    2016-01-01

    In this paper temperature and precipitation data observed from 128 meteorological stations in Northwest China from 1961 to 2010 were used to explore the spatial and temporal distribution of spring droughts.For this purpose,the standardized precipitation e-vapotranspiration index (SPEI),the intensity and frequency of spring drought were calculated and analyzed with methods of climate statistical analysis and wavelet analysis.The results are as follows:(1 )In Turpan Depression,Tarim Basin of Xinjiang,Qaidam Basin of Qinghai and Longnan of Gansu Province,the spring droughts were most serious and occurred frequently,while in the eastern region of north Tianshan Mountain in Xinjiang it occurred least.(2)The average intensity of spring droughts over the study area strengthened significantly with a rate of 0.259 per 10 years,and the frequency of moderate drought events increased significantly at a rate of 0.033 times per 10 years.In the 1980s the intensity of spring droughts fell to the weakest and the total frequency reduced,while in the 2000s both of them rose to the strongest and the maximum.Meanwhile,spring droughts presented general increasing trend in these 5 prov-inces in recent 50 years.(3)The frequency of spring droughts displayed cyclical oscillation with scales of 3 years,9 years and 25 years above,and among them,the 3 years period passed through the significant test of red noise.The above results indicated that spring droughts in Northwest China presented distinct spatial and temporal variations.%利用西北地区128个气象台站1961~2010年的气温和降水数据,计算了标准化降水蒸散指数(SPEI),并结合气候统计分析和小波分析方法,探讨了西北地区春旱的时空分布特征。结果表明:(1)西北地区春旱程度重、次数多的地区位于新疆吐鲁番盆地、塔里木盆地、青海柴达木盆地和甘肃陇南地区,程度轻、次数少的地区位于新疆天山以北的东部地区;(2)

  16. 西北旱区葡萄园土壤水分空间分布研究%Spatial Distribution of Soil Moisture in Vineyard in Arid Region of Northwest China

    Institute of Scientific and Technical Information of China (English)

    周宏民; 于海燕

    2012-01-01

    研究于我国西北旱区武威市一葡萄园内进行,根据葡萄行走向按照30m×30m设置网格,共设计60个采样点。测定表层(10~20cm)、葡萄根区(20~80cm)、深层(80~100cm)3个层次土壤水分。采用传统统计与地统计相结合的方法对土壤水分空间分布状况进行分析,结果表明,各层次土壤水分均服从正态分布,具有中等变异强度,并随着深度的增加呈现出先增加后减小的趋势;各层次土壤水分具有较强的空间相关性,其理论变异函数的有效变程分别为117.04、167.92、174.81m;采用克立格插值方法绘制的各层次土壤水分分布图可以为灌溉制度的制定提供参考。并给出了不同置信水平及精度要求下的合理取样数目。%The arid region of Northwest China has become a major wine grape cultivation base,and the soil moisture is important for grape growth and quality.So we need to obtain accurate soil moisture condition for fine irrigation management.The research was carried out at a vineyard in Wuwei City which located at an arid region in Northwest China,and sixty sampling points collected on a 30 m grid.Soil moisture was measured at three depths in soil profile: 10~20 cm for the soil surface,20~80 cm in grape root zone,80~100 cm in deep layer.The data was analyzed with a combination of classical statistics and geological statistic.The research results showed that all layers of soil moisture were normal distribution,and all the layers of soil moisture exhibited moderate spatial variability,in the tendency of increasing first and then decreasing with depth increases;and all soil water was correlated in spatial range,the range of theoretical variation functions of soil moisture correlation distance was 117.04 m,167.92 m and 174.81 m;The soil moisture distribution map which was charted by Kriging interpolating can provide reference for formulating irrigation system;The rational sampling number for soil moisture was

  17. Genetic analysis of the br gene in halophilic archaea isolated from Xinjiang region, China

    Institute of Scientific and Technical Information of China (English)

    Xiaohong XU; Min WU; Huibin ZHANG; Zhihu LIU

    2008-01-01

    Some novel members of extremely halophilic archaea, strains AJ 11, AJ 12 and AJ 13, were isolated from the Aularz Lake located in the Altun Mountain National Nature Reserve of Xinjiang, Uygur Autonomous Region in China. Partial DNA fragments encoding a bacteriorho-dopsin (BR), as well as for 16S rRNA of isolated strains, were amplified by PCR and their DNA sequences were determined subsequently. On the basis of homology and phylogenetic analysis of the 16S rDNA, we thought that the isolated strains forming a microbiological population are the members of the genus Natrinema. The results of genetic analysis, such as GC content, transition/transver-sion (Ti/Tv) rate ratios and synonymous substitution rates (Ks) indicate that the br fragments, with a high level of genetic divergence, are faced with both purifying selection and bias mutation pressure. The study provides the basis for use of species and BR proteins resources.

  18. 黑河中游沙枣的传粉生物学研究%Pollination Biology of Elaeagnus angustifolia in Middle Reaches of the Heihe River in Northwest China

    Institute of Scientific and Technical Information of China (English)

    潘成臣; 刘林德; 赵哈林; 侯月利; 张莉; 王丽娟

    2012-01-01

    Pollen fertility, pollen/ovule ratio, pollen viability and longevity, and pollen histochemistry of Elaeagnus angustifolia were determined in the Linze Inland River Research Station in the middle reaches of Heihe River in Northwest China. The pollen of E. angustifolia is of starch type. The pollen viability is higher than 90 % within the 6 hours after anthesis on sunny days and lower than 3 % at the beginning of an- thesis in rainy days. No difference in the pollen production of single flowers is found between different flow- er morphes (three or four petals). The pollen/ovule ratios of the two morph flowers are 15 250±1 497, 14 143±1 438, respectively.%在甘肃省临泽县黑河中游的中国生态系统研究网络临泽内陆河流域研究站试验区对沙枣花粉育性、花粉-胚珠比(P/O)、花粉活力与寿命、花粉储存物类型等进行了观测。结果表明,沙枣花粉为全育的淀粉型花粉;晴天时,花药散粉后6h内,花粉活力维持在90%以上;雨天时,花药散粉后,花粉活力即低于3%;三瓣花、四瓣花单花产生的花粉量无显著性差异,P/O分别为15 250±1 497、14 143±1 438。

  19. [Effects of different tillage and fertilization modes on the soil physical and chemical properties and crop yield under winter wheat/spring corn rotation on dryland of east Gansu, Northwest China].

    Science.gov (United States)

    Zhang, Jian-jun; Wang, Yong; Fan, Ting-lu; Guo, Tian-wen; Zhao, Gang; Dang, Yi; Wang, Lei; Li, Shang-zhong

    2013-04-01

    Based on the 7-year field experiment on the dryland of east Gansu of Northwest China in 2005-2011, this paper analyzed the variations of soil moisture content, bulk density, and nutrients content at harvest time of winter wheat and of the grain yield under no-tillage and conventional tillage and five fertilization modes, and approached the effects of different tillage and fertilization modes on the soil water storage and conservation, soil fertility, and grain yield under winter wheat/ spring corn rotation. In 2011, the soil moisture content in 0-200 cm layer and the soil bulk density and soil organic matter and available nitrogen and phosphorus contents in 0-20 cm and 20-40 cm layers under different fertilization modes were higher under no-tillage than under conventional tillage. Under the same tillage modes, the contents of soil organic matter and available nitrogen and available phosphorus were higher under the combined application of organic and inorganic fertilizers, as compared with other fertilization modes. The soil available potassium content under different tillage and fertilization modes decreased with years. The grain yield under conventional tillage was higher than that under no-tillage. Under the same tillage modes, the grain yield was the highest under the combined application of organic and inorganic fertilizers, and the lowest under no fertilization. In sum, no-tillage had the superiority than conventional tillage in improving the soil water storage and conservation and soil fertility, and the combined application of organic and inorganic fertilizers under conventional tillage could obtain the best grain yield.

  20. Co-occurrence of arseniasis and fluorosis due to indoor combustion of high fluorine and arsenic content coal in a rural township in northwest China: epidemiological and toxicological aspects.

    Science.gov (United States)

    Lin, Guo-fang; Gong, Shi-you; Wei, Cheng; Chen, Ji-gang; Golka, Klaus; Shen, Jian-hua

    2012-06-01

    A large number of fluorosis and arseniasis cases appeared in a mountainous area in northwest China. The residents relied on local inferior coal ("bone coal") of high fluorine and arsenic content for domestic heating and cooking. For deep-inside information about this rare case of co-endemia of fluorosis and arseniasis in the population in this special exposure scenario, a field investigation in one of the hyperendemic townships was conducted. The resident population registered (n = 27,713) was enrolled in the investigation. All cases were diagnosed and assigned to three symptom severity groups, that is severe, medium, and mild according to Chinese National Standard Criteria GB 16396-96 and to the technical guideline WS/T208-01 or WS/T211-01 issued by the Chinese Ministry of Health. Gender difference was analyzed by standardized incidence ratio. Age trend and severity trend were tested by χ(2) analysis. Fluorosis was diagnosed in 56.7% of the residents. Over 95% of the diagnosed arseniasis cases were simultaneously diagnosed with fluorosis symptoms. Combined fluorosis-arseniasis represented 11.9% of the total fluorosis cases and 6.7% of the local population. No gender-related differences in the prevalence of skeletal, dental, or dermal symptoms inside all severity groups were detected. Symptom severity increased with age. The high frequency of superposition of arseniasis with fluorosis might be due to the fact that the local resident population has been exposed to very high levels of fluorine and arsenic via the same exposure route.

  1. The Study on the Recirculation System for Landfill Leachate in Northwest of China%西北卫生填埋场渗滤液回灌系统研究

    Institute of Scientific and Technical Information of China (English)

    徐燕; 苟剑锋; 曾正中; 吴凯; 张贺飞

    2011-01-01

    回灌技术是一种简单、低廉的渗滤液处理技术,可有效降低渗滤液中COD和氨氮的含量,加速填埋场内垃圾的降解,提高产甲烷速率和甲烷的产量,增大填埋场的沉降速率和总沉降幅度,缩短填埋场的维护期.回灌技术能够适应渗滤液水质水量的复杂变化,在我国西北地区有非常广阔的应用前景.同时,由于该技术在我国利用过程中尚缺乏成熟的工艺设计和运行经验,所以还有待进一步研究和实践.%Recirculation is a simple and cheap way for dealing with the landfill leachate. It can effectively reduce the contents of COD and ammonia nitrogen in leachate. It also can accelerate the degradation of landfill waste,improve methane production rate and methane production. It increase the rate of sedimentation and the extent of sedimentation,shorten the maintenance period of landfill. Recirculation is suit for the changes of quality and quantity of leachate and can be widely used in Northwest of China. But there was still lack of maturity in the use of process design and operation experience, so it needed the further research and practice.

  2. Combined multivariate statistical techniques, Water Pollution Index (WPI and Daniel Trend Test methods to evaluate temporal and spatial variations and trends of water quality at Shanchong River in the Northwest Basin of Lake Fuxian, China.

    Directory of Open Access Journals (Sweden)

    Quan Wang

    Full Text Available Understanding spatial and temporal variations in river water quality and quantitatively evaluating the trend of changes are important in order to study and efficiently manage water resources. In this study, an analysis of Water Pollution Index (WPI, Daniel Trend Test, Cluster Analysis and Discriminant Analysis are applied as an integrated approach to quantitatively explore the spatial and temporal variations and the latent sources of water pollution in the Shanchong River basin, Northwest Basin of Lake Fuxian, China. We group all field surveys into 2 clusters (dry season and rainy season. Moreover, 14 sampling sites have been grouped into 3 clusters for the rainy season (highly polluted, moderately polluted and less polluted sites and 2 clusters for the dry season (highly polluted and less polluted sites based on their similarities and the level of pollution during the two seasons. The results show that the main trend of pollution was aggravated during the transition from the dry to the rainy season. The Water Pollution Index of Total Nitrogen is the highest of all pollution parameters, whereas the Chemical Oxygen Demand (Chromium is the lowest. Our results also show that the main sources of pollution are farming activities alongside the Shanchong River, soil erosion and fish culture at Shanchong River reservoir area and domestic sewage from scattered rural residential area. Our results suggest that strategies to prevent water pollutionat the Shanchong River basin need to focus on non-point pollution control by employing appropriate fertilizer formulas in farming, and take the measures of soil and water conservation at Shanchong reservoir area, and purifying sewage from scattered villages.

  3. Co-occurrence of arseniasis and fluorosis due to indoor combustion of high fluorine and arsenic content coal in a rural township in northwest China: epidemiological and toxicological aspects

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Guo-fang; Shen, Jian-hua [Chinese Academy of Sciences, Shanghai Institutes for Biological Sciences, Institute of Plant Physiology and Ecology, Shanghai (China); Gong, Shi-you [County Center for Disease Control and Prevention of Ziyang, Ziyang, Shaanxi (China); Wei, Cheng [Township Clinics of Haoping, Ziyang, Shaanxi (China); Chen, Ji-gang [Municipal Center for Disease Prevention and Control of Shanghai, Shanghai (China); Golka, Klaus [Leibniz Research Centre for Working Environment and Human Factors (IfADo), Dortmund (Germany)

    2012-06-15

    A large number of fluorosis and arseniasis cases appeared in a mountainous area in northwest China. The residents relied on local inferior coal (''bone coal'') of high fluorine and arsenic content for domestic heating and cooking. For deep-inside information about this rare case of co-endemia of fluorosis and arseniasis in the population in this special exposure scenario, a field investigation in one of the hyperendemic townships was conducted. The resident population registered (n = 27,713) was enrolled in the investigation. All cases were diagnosed and assigned to three symptom severity groups, that is severe, medium, and mild according to Chinese National Standard Criteria GB 16396-96 and to the technical guideline WS/T208-01 or WS/T211-01 issued by the Chinese Ministry of Health. Gender difference was analyzed by standardized incidence ratio. Age trend and severity trend were tested by {chi}{sup 2} analysis. Fluorosis was diagnosed in 56.7% of the residents. Over 95% of the diagnosed arseniasis cases were simultaneously diagnosed with fluorosis symptoms. Combined fluorosis-arseniasis represented 11.9% of the total fluorosis cases and 6.7% of the local population. No gender-related differences in the prevalence of skeletal, dental, or dermal symptoms inside all severity groups were detected. Symptom severity increased with age. The high frequency of superposition of arseniasis with fluorosis might be due to the fact that the local resident population has been exposed to very high levels of fluorine and arsenic via the same exposure route. (orig.)

  4. RS、GIS、GPS在西北农业大开发中的应用前景%Prospects of Applying RS, GIS and GPS Technologies to Agricultural Development in the Northwest of China

    Institute of Scientific and Technical Information of China (English)

    王鹏新; 龚健雅; 李小文

    2000-01-01

    Remote sensing (RS), geographic information system (GIS) and global positioning system (GPS),known as ’3S’ technologies, can be applied to agricultural fields separately or in combinations. These technologies are used to obtain multidimensional information, especially for temporal series, in agricultural production systems, to manage and process spatial and attribute data comprehensively, to propose related information for agricultural decision-makers and farmers, and further to provide guidelines for the regional agricultural production and sustainable development. In this paper, the prospects of applying these technologies to develop agricultural production in the Northwest of China were discussed. The discussions were centralized on retrievals of land surface temperature and soil moisture, and on monitoring of drought occurrence and desertification dynamically, and on management of the data as well. Most areas of the Northwest China belong to arid and semi-arid areas where rainfall is low and with uneven spatial and temporal distributions. Rainfed agriculture is popular in the region. Many field studies showed that there are two main constraints for the region’s agricultural development, one is the shortage of soil water supply and another is that soil fertility is low. The soil water shortage is often occurred over a large area, therefore, the only way to monitor the shortage and to estimate its extent is using remote sensing technology. For bare soil or soil with sparse vegetation coverage, remotely sensed data can be used to model soil thermal inertia, and further to model soil moisture. Taking NOAA advanced very high resolution radiometer (AVHRR) data as a example, firstly, channel 1 (0. 58~0. 68 μm) and channel 2 (0. 72~1.10 μm) can be used to retrieve soil surface albedo, and for channel 4 (10. 3~11.3 μm) and channel 5 (11.5~12.50 μm) to retrieve land surface temperature by the so-called spilt window

  5. The soil-water flow system beneath a cotton field in arid north-west China, serviced by mulched drip irrigation using brackish water

    Science.gov (United States)

    Li, Xianwen; Jin, Menggui; Huang, Jinou; Yuan, Jingjing

    2015-02-01

    A field experiment was carried out in southern Xinjiang, China, to reveal soil-water flow pattern beneath a combined plastic-mulch (film) and drip-irrigation system using brackish water. The soil-water flow system (SWFS) was characterized from soil surface to the water table based on observed spatio-temporal distribution of total soil-water potential, water content and electric conductivity. Root suction provided a strong inner sink. The results indicated that SWFS determined the soil salinity and moisture distribution. Drip-irrigation events could leach excess salts from the root zone and provide soil conditions with a tolerable salinity level that supports the growth of cotton. High-salinity strips were formed along the wetting front and at the bare soil surface. Hydrogeology conditions, irrigation regime, climate, plant growth and use of mulch would affect potential sources and sinks, boundary conditions and the size of the SWFS. At depth 0-60 cm, the soil salinity at the end of the irrigation season was 1.9 times that at the beginning. Beneath the mulch cover, the soil-water content in the `wide rows' zone (55 cm between the two rows with no drip line) was higher than that in the `narrow rows' zone (15 cm between the two rows with a drip line) due to the strong root-water uptake. The downward water flow below the divergent curved surface of zero flux before irrigation, and the water-table fluctuation with irrigation events, indicated that excessive irrigation occurred.

  6. [Effects of different straw-returning regimes on soil organic carbon and carbon pool management index in Guanzhong Plain, Northwest China].

    Science.gov (United States)

    Li, Shuo; Li, You-bing; Wang, Shu-juan; Shi, Jiang-lan; Tian, Xiao-hong

    2015-04-01

    A four-year (2008-2012) field experiment was conducted to investigate the effects of different straw-returning regimes on soil total organic carbon (TOC), labile organic carbon (LOC) and the ratio of LOC to TOC (LOC/TOC) as well as TOC stock (SCS) and soil carbon pool management index (CPMI) in a farmland with maize-wheat double cropping system in Guanzhong Plain area, Shaanxi Province, China. The results indicated that soil TOC and LOC contents and SCS were significantly increased when wheat or maize straw was returned to field, and the increasing extent showed the rising order as follows: double straw-returning > single straw-returning > no straw-returning. Compared to no straw returning, a significant increase of TOC and LOC contents and SCS was found in the treatment of wheat straw chopping retention combined with maize straw chopping subsoiling retention (WC-MM), and CPMI of WC-MM was significantly higher than in the other treatments in 0-20 cm soil layer. Compared to no wheat straw returning, soil CPMIs in 0-10 cm and 10-20 cm soil layer increased by 19.1% and 67.9% for the wheat straw chopping returning treatment, and by 22.6% and 32.4% for the maize straw chopping subsoiling treatment, respectively. Correlation analysis showed that soil CPMI was a more effective index reflecting the sequestration of soil organic carbon in 0-30 cm soil layer than the ratio of LOC to TOC. This study thus suggested that WC-MM regime is the best straw-returning regime for soil organic carbon sequestration.

  7. The response of aboveground net primary productivity of desert vegetation to rainfall pulse in the temperate desert region of northwest China.

    Science.gov (United States)

    Li, Fang; Zhao, Wenzhi; Liu, Hu

    2013-01-01

    Rainfall events can be characterized as "pulses", which are discrete and variable episodes that can significantly influence the structure and function of desert ecosystems, including shifts in aboveground net primary productivity (ANPP). To determine the threshold and hierarchical response of rainfall event size on the Normalized Difference Vegetation Index (NDVI, a proxy for ANPP) and the difference across a desert area in northwestern China with two habitats - dune and desert - we selected 17 independent summer rainfall events from 2005 to 2012, and obtained a corresponding NDVI dataset extracted from MODIS images. Based on the threshold-delay model and statistical analysis, the results showed that the response of NDVI to rainfall pulses began at about a 5 mm event size. Furthermore, when the rainfall event size was more than 30 mm, NDVI rapidly increased 3- to 6-fold compared with the response to events of less than 30 mm, suggesting that 30 mm was the threshold for a large NDVI response. These results revealed the importance of the 5 mm and 30 mm rainfall events for plant survival and growth in desert regions. There was an 8- to 16-day lag time between the rainfall event and the NDVI response, and the response duration varied with rainfall event size, reaching a maximum of 32 days. Due to differences in soil physical and mineralogical properties, and to biodiversity structure and the root systems' abilities to exploit moisture, dune and desert areas differed in precipitation responses: dune habitats were characterized by a single, late summer productivity peak; in contrast, deserts showed a multi-peak pattern throughout the growing season.

  8. The response of aboveground net primary productivity of desert vegetation to rainfall pulse in the temperate desert region of northwest China.

    Directory of Open Access Journals (Sweden)

    Fang Li

    Full Text Available Rainfall events can be characterized as "pulses", which are discrete and variable episodes that can significantly influence the structure and function of desert ecosystems, including shifts in aboveground net primary productivity (ANPP. To determine the threshold and hierarchical response of rainfall event size on the Normalized Difference Vegetation Index (NDVI, a proxy for ANPP and the difference across a desert area in northwestern China with two habitats - dune and desert - we selected 17 independent summer rainfall events from 2005 to 2012, and obtained a corresponding NDVI dataset extracted from MODIS images. Based on the threshold-delay model and statistical analysis, the results showed that the response of NDVI to rainfall pulses began at about a 5 mm event size. Furthermore, when the rainfall event size was more than 30 mm, NDVI rapidly increased 3- to 6-fold compared with the response to events of less than 30 mm, suggesting that 30 mm was the threshold for a large NDVI response. These results revealed the importance of the 5 mm and 30 mm rainfall events for plant survival and growth in desert regions. There was an 8- to 16-day lag time between the rainfall event and the NDVI response, and the response duration varied with rainfall event size, reaching a maximum of 32 days. Due to differences in soil physical and mineralogical properties, and to biodiversity structure and the root systems' abilities to exploit moisture, dune and desert areas differed in precipitation responses: dune habitats were characterized by a single, late summer productivity peak; in contrast, deserts showed a multi-peak pattern throughout the growing season.

  9. Usefulness of pumpkin seeds combined with areca nut extract in community-based treatment of human taeniasis in northwest Sichuan Province, China.

    Science.gov (United States)

    Li, Tiaoying; Ito, Akira; Chen, Xingwang; Long, Changping; Okamoto, Munehiro; Raoul, Francis; Giraudoux, Patrick; Yanagida, Tetsuya; Nakao, Minoru; Sako, Yasuhito; Xiao, Ning; Craig, Philip S

    2012-11-01

    Taeniasis refers to the infection with adult tapeworms of Taenia spp. in the upper small intestine of humans, which is also a cause of cysticercosis infection in either both humans and/or animals. Currently the most commonly applied anthelminthics for treatment of taeniasis are praziquantel and niclosamide. Praziquantel is very effective, but has the risk of induction of epileptic seizures or convulsions in carriers with asymptomatic concurrent neurocysticercosis. In contrast, niclosamide is safe and effective, but is not readily available in many endemic countries including China. In the current community-based study, we assessed the curative effect of either pumpkin seeds or areca nut extract alone in taeniasis, and also looked at synergistic effects of these two herb drugs on tapeworms. In the study group with the pumpkin seed/areca nut extract treatment, 91 (79.1%) of 115 suspected taeniasis cases (with a history of expulsion of proglottids within the previous one year) released whole tapeworms, four (3.5%) expelled incomplete strobila, and no tapeworms or proglottids were recovered in the remaining 20 cases. In these 115 persons, 45 were confirmed as taeniasis before treatment by microscopy and/or coproPCR. Forty (88.9%) of 45 confirmed cases eliminated intact worms following treatment. The mean time period for complete elimination of tapeworms in 91 taeniasis cases was 2 h (range 20 min to 8 h 30 min), and 89.0% (81) of 91 patients discharged intact worms within 3h after drug administration. In Control Group A with treatment of pumpkin seeds alone, 75.0% (9/12) of confirmed taeniasis cases expelled whole tapeworms, but the mean time period for complete elimination was about 14 h 10 min (range 3 h 20 min to 21 h 20 min), which was much longer than that (2 h) for the study group, whereas in Control Group B treated with areca nut extract alone, only 63.6% (7/11) of taeniasis cases discharged whole tapeworms, and the mean time period was 6 h 27 min (range 1-22 h

  10. 塔里木盆地现今地热特征%Present-day geothermal regime in Tarim basin, northwest China

    Institute of Scientific and Technical Information of China (English)

    冯昌格; 刘绍文; 王良书; 李成

    2009-01-01

    Geothermal gradient and terrestrial heat flow are key parameters that describe the thermal regime of sedimentary basin,and are so vital for understanding the tectono-thermal evolution and associated hydrocarbon resource potential assessment of oil and gas bearing basin.Here we show the distribution pattern of the updated present-day geothermal gradient and calculate 38 terrestrial heat flow values in the Tarim basin,one of the biggest sedimentary basins in China,based on the formation temperature data from approximately 470 wells and 941 thermal conductivity of rocks within this basin.Our results show that the present-day geothermal gradient of Tarim basin varies between 17~32 ℃/km with a mean value of 22.6±3.0 ℃/km, and the terrestrial heat flow ranges from 26.2 to 65.4 Mw/m~2 with a mean of 43.0±8.5 Mw/m~2,suggesting a thermal regime of cold basin with low temperature and low heat flow,as compared with other large-middle scale sedimentary basins in China.This low thermal regime also makes Tarim basin to share the similar geothermal characteristics of other typical craton basins in the world.Generally,the geothermal gradient and terrestrial heat flow in uplift areas are usually larger than those in the depressions.We also find that the discovered oil and gas fields in Tarim are usually with relatively large geothermal gradient,the cause for this coincidence is not clear but the upward movement and accumulation of hot fluid below is speculated to account for this positive geothermal anomaly.Finally,we summarize the factors that influence the geothermal distribution of basin as deep structure,tectonic evolution and basement pattern of basin,thermal physical properties of rocks and hydrocarbon accumulation as well.%地温梯度和大地热流是揭示盆地现今热状态的重要参数,它们对理解盆地的构造一热演化过程及油气资源评价等方面均具有重要意义.利用塔里木盆地约470口井的地层测试温度资料和941

  11. 和谐与共荣:新时期西北地区残疾人体育健身服务保障体系的构建%Harmony and Common Prosperity: Discussion on the Con- struction of Sports Fitness Service System of Persons with Disa- bilities in Northwest Region of China in the New Period

    Institute of Scientific and Technical Information of China (English)

    张健; 张建华

    2012-01-01

    Using the research methods of literature, comparative a- nalysis and social investigation, the paper analyzed the current de- velopment of sports for the disabled in Northwest region of China. The results showed that: under certain economic conditions in Northwest region of China, internal and external factors can influ- ence the sports participation among persons with disabilities, inter- nal factors can be influenced and restricted by social factors, while social factors can be restricted by subjective desire of disabilities who moving to fitness. Therefore, by using the disabled sports fit- ness market innovation, institutional facilities, public opinion guid- ance, operation security, education and employment, building the sports fitness service system of persons with disabilities in Northwest region of China in the new period.%运用文献资料、比较分析和社会调查等研究方法,对西北地区残疾人体育发展现状进行分析。研究表明:在西北地区特定的经济条件下,影响残疾人体育健身的因素包括内因和外因两个方面,其中自身因素受社会因素的影响与制约,而社会因素则受动于残疾人体育健身主观愿望。因此,从残疾人体育健身市场开拓创新、制度配套、舆论引导、运行保障以及残疾人受教育和就业等方面,为新时期西北地区构建残疾人体育健身保障体系提供具体建议。

  12. Decomposition of different plant litters in Loess Plateau of Northwest China%黄土高原不同植物凋落物的分解特性

    Institute of Scientific and Technical Information of China (English)

    李云; 周建斌; 董燕捷; 夏志敏; 陈竹君

    2012-01-01

    Taking the litters of species Hippophae rhamnoides, Medicago sativa, Populus simonii, Robinia pseudoacaci, Salix psammophila, and Stipa bungeana in the Loess Plateau of Northeast China as test objects, and by using mesh bags, this paper studied the dynamic changes of the litters mass, carbon, and nitrogen during decomposition after buried in the field in semiarid region. The litters buried were from one, two, or three of the plant species, and mixed thoroughly with equal proportion of masses. During decomposition, the mass loss rate, total carbon and nitrogen release rates, and total soluble carbon and nitrogen contents of different litters were higher at the early than at the later decomposition stage. After 412 d decomposition, the average mass loss rate of the litters was in the order of mixed litters of three plant species > mixed litters of two plant species > one plant species litter. By the end of this experiment, the average release rates of the litter total carbon and nitrogen ranked as one plant species litter > mixed litters of two plant species > mixed litters of three plant species, the litter soluble organic carbon content was mixed litters of two plant species > mixed litters of three plant species > one plant species litter, while the litter soluble total nitrogen content was mixed litters of three plant species > mixed litters of two plant species > one plant species litter. Correlation analysis showed that the utter mass loss rate had definite correlation with the litter soluble organic matter, especially soluble organic carbon. From the viewpoint of mass loss rate, the mixture of the litters of P. simonii, H. rhamnoide, and M. sativa was the optimum. It was suggested that in the process of returning farmland into forestland and grassland in the gully and valley region of Loess Plateau, it would be required to rationally increase plant species diversity to improve soil fertility.%以黄土高原区典型植物刺槐、小叶杨、沙棘、沙柳

  13. Soil salinization control and sustainable agriculture in north-west endoland region of China%中国西北内陆盐渍化防治与可持续农业的研究

    Institute of Scientific and Technical Information of China (English)

    贾恢先

    2003-01-01

    There are large amount of salinized soil in north-west region.Salinization is a main reason that cause a bad ecological environment and prevent to develop sustainable agriculture.The reasons for salinization is variable.Because salinity soil have characteis such as intensified salinity degree,complicated salt contents,weak rain off salt-washing off,obvious salt surface concentration,second salinity distributed more often and water movement unable to take away the salinity in the soil.So it is more hard to prevent salinization inland than in areas near sea.After 20 years of studies,we have taken a biological approach involving planting special salt tolerant crops,through which take away salt increase green-coverd areas as to prevent salts up to the subsoil,therefore to improve soil production efficiently.Mean while,we insist on study.mechanic of plant salt-resist and measures about how to use of these plants so that a practical and theoretical basement of salinization prevention was founded.Also models of "grass industry in salinized areas" and "medical plants industry in salinized areas" are presented,this be sure to lead to obvious ecological,social and ecological efficiency of sustained agriculture in salinized areas in north-west China.%中国西北内陆分布着广袤的盐渍土是影响生态环境和农业可持续发展的一个重要因素.由于盐渍成因多样、盐渍程度强烈、盐分组成复杂、雨水淋盐微弱、表聚作用显著、次生盐渍普遍和单纯用水无法把盐排走等特点,因而相对治理难度比沿海地区更大.作者通过20多年的研究,采用生物防治为主的办法,通过引种盐地先锋植物、应用生物排盐、增大绿色覆盖、防止盐分表聚、培肥地力等措施,使土地能有效地脱盐.同时坚持对植物抗盐机理和盐地资源植物开发利用的研究,使内陆盐渍生物防治建立在理论和应用的基础上.并根据改善西部生态环境,调整种植结

  14. Northwest Coast Indian Art.

    Science.gov (United States)

    Manning, Thomas; Knecht, Elizabeth

    The visual art forms of the Northwest Coast Indian Tribes of Alaska (Haida, Tlingit, and Tsimshian) share common distinctive design elements (formline, ovoid, U-form, and curvilinear shapes) which are referred to as the "Northern Style." Designs represent events or characters taken from the oral tradition of song and legend.…

  15. Suicide in Northwest Alaska.

    Science.gov (United States)

    Travis, Robert

    1983-01-01

    Between 1975 and 1979 the Alaskan Native suicide rate (90.9 per 100,000) in Northwest Alaska was more than seven times the national average. Alienation, loss of family, low income, alcohol abuse, high unemployment, and more education were factors related to suicidal behavior. Average age for suicidal behavior was 22.5. (Author/MH)

  16. Risk Analysis and Safety Evaluation of Crude Oil Depot in Northwest China%西北地区原油库风险分析及安全度评价

    Institute of Scientific and Technical Information of China (English)

    刘艳东; 陈红兵; 王莉; 许洁; 曲皓

    2016-01-01

    油品储存一旦发生泄漏事故,会造成环境污染以及十分严重的经济损失。以西北地区某油库为例,根据原油库划分各功能单元,将其视为子系统,对相关风险因素进行归类、分析,运用预先危险分析方法划分危险等级,对油库各项目进行分析后,确定出各功能单元子系统危险因素,结合安全检查表法对该油库进行了风险评价及安全度评估。通过计算分析得出:该油库属于基本安全型,原油泄漏引发的火灾及爆炸事故是油库的主要危险;油库的储罐组、输油泵房和计量间的固有火灾危险很大,须进行补偿计算。%Once the oil storage leakage accident, environmental pollution and serious eco-nomic losses will be caused.Taking a depot in Northwest China as an example,classified ac-cording to the functional units of the crude oil which is regarded as a subsystem,the subsys-tem of related risk factors were classified and analyzed, using the pre risk analysis method to classify the risk level,after analyzing the items of the oil depot,the risk factors of each func-tional unit subsystem are determined, and the risk assessment and safety evaluation of the oil storage tank are carried out by the combination of the safety check list method.Through cal-culation and analysis, it is concluded that:the oil depot belongs to the basic safety type, and the main risk is fire and explosion accident caused by oil spill;the inherent fire risk from the oil storage tank, oil pumping stations and measurement room is great, the compensation shall be calculated is necessary.

  17. Middle Jurassic Sporo-pollen Assemblages in Northern Turpan Depression, Xinjiang, Northwest China%吐鲁番拗陷北部中侏罗世孢粉植物群

    Institute of Scientific and Technical Information of China (English)

    尹凤娟; 张子福

    2002-01-01

    Eighty-one species of fossil spores and pollen assigned to 52 genera are found from the Middle Jurassic Xishanyao,Sanjianfang and Qiketai Formations of boreholes Le 1, Mi 1, Shan 1 and Dun 1 in the northern Turpan Depression, Xinjiang, northwest China. Three assemblages have been proposed as: Cyathidites-Psophosphaera-Cycadopites assemblage, Cyathidites-Quadraeculina-Classopollis assemblage and Cyathidites-Callialasporites-Classopollis assemblage obtained from the Xishanyao Formation, the Sanjianfang Formation and Qiketai Formation respectively. Based on the sporo-pollen assemblage features and correlation,their geological ages are regarded as of Middle Jurassic,probably Aalenian to Bathonian.The results of the study indicate that the vegetation of early Middle Jurassic in this region consisted mainly of Gymnospermae of Ginkgoaceae of Cycadales, Podocarpaceae, Pinaceae and Pteridophyta of Cyatheaceae, Osmundaceae, Lycopodiaceae and Dicksoniaceae, etc. They reflect a warm-moist subtropic climate.To the middle-late Middle Jurassic, Cheirolepidaceae was dominant in the vegetation, which indicates that the climate was in the trend of becoming dry.%报道了新疆吐鲁番拗陷北部勒1、米1 、山1和墩1井中侏罗世孢粉化石52属81种.建立了本区中侏罗世孢粉组合: Cyathidites-Psophosphaera-Cycadopite 组合、 Cyathidites-Quadraeculina-Classopollis 组合和 Cyathidites-Callialasporites-Classopollis 组合.它们分别产自西山窑组、三间房组和七克台组.根据孢粉组合特征及其对比, 认为3个组合的地质时代属阿林-巴通期.经研究表明, 中侏罗世早期的植被是以银杏、苏铁类和松柏类等乔木为主体, 并伴有桫椤科树蕨及紫萁科和卷柏科等草本植物.古气候应属温暖潮湿的亚热带气候.至中侏罗世中晚期, 掌鳞杉科植物在植被中占主导地位, 指示当时的气候趋于干旱.

  18. Desertification Process and Its Spatial Differentiation in Arid Areas of Northwest China%我国西北干旱区的荒漠化过程及其空间分异规律

    Institute of Scientific and Technical Information of China (English)

    赵哈林; 赵学勇; 张铜会; 张小由; 李玉霖; 刘立超

    2011-01-01

    我国西北干旱区的荒漠化可以归结为荒漠的荒漠化和绿洲的荒漠化两种类型.其中,荒漠的荒漠化主要表现为沙漠化,主要发生于土质荒漠和沙质荒漠.土质荒漠沙漠化的最终结果将由土质荒漠演变为沙质荒漠或砾质荒漠或风蚀劣地,沙质荒漠的沙漠化是由固定、半固定沙质荒漠演变为流动、半流动沙质荒漠的过程,其最终结果是形成流动沙质荒漠.绿洲的荒漠化主要包括绿洲的干旱化、沙漠化和盐渍化3种类型.其中,干旱化常导致绿洲植被的衰退和死亡,致使绿洲萎缩,其边缘地带常和沙漠化叠加,导致流沙对绿洲的入侵.如果绿洲水源完全断绝,其绿洲将会消失,最终演变为沙质荒漠或风蚀劣地.绿洲盐渍化主要源于过度灌溉导致地下水位抬升,下层土壤盐分聚集地表所致.其结果是形成盐渍化绿洲.我国西北地区土质荒漠的荒漠化主要发生于内蒙古阿拉善地区的东部、天山南麓冲积扇上的土质荒漠带,以及准噶尔盆地北侧的荒漠草原带;沙质荒漠的荒漠化主要发生于准噶尔盆地的古尔班通古特沙漠.绿洲干旱化和沙漠化以甘肃民勤最为典型,而绿洲的盐渍化主要发生于新疆阿克苏、喀什地区一带.%Land desertification in arid areas of northwest China could be classified as two types: desert desertification and oasis desertification. Desert desertification presents mostly aeolian desertification, which occurs mainly in terrene desert and sandy desert. As final result of desertification, terrene desert turns into sandy desert, gravel desert or aeolian land. Desertification of sandy desert is a process that fixed and semifixed desert turn into mobile or semi-mobile desert, which results finally in formation of mobile desert. Oasis desertification includes main three types: aridilization, aeolian desertification and salinization. Oasis aridilization results normally in degeneration and

  19. 西北通用机场选址气候论证关键评估指标研究%Study of the Critical Meteorological Evaluation Indexes for the General Airport Site Selection in the Northwest China

    Institute of Scientific and Technical Information of China (English)

    崔洋; 常倬林; 左河疆; 孙银川

    2014-01-01

    Based on investigating the connections between the various meteorological elements and the general airport site selection,the key meteorological evaluation indexes for general airport site selection in northwest China and the important extent of these indexes were analyzed.Then,the Shahu general airport proposed site was evaluated by using the observational data from Pingluo weather station dur-ing 2000-2009 and the temporary weather station observational data from 201 1 to 2012 in the proposed site.The results show that wind speed,wind direction,visibility,cloud amount,cloud form and cloud height are the important meteorological elements that need to be considered in site selection of the general airport in northwest China.Meanwhile,the meteorological evaluation indexes of the general airport site selection can be roughly divided into six categories.Among them,the indexes of class I-III are the critical indexes which decide whether or not to build the general airport on the proposed site,and the indexes of class IV and V are the important refer-ence indexes for the proposed site’s operation efficiency evaluation,engineering design and the investment calculation,while the class VI is mainly used in the special proposed site evaluation.The Shahu general airport proposed site has the prevailing wind direction,low wind speed,excellent visibility conditions and the less thunderstorm,gale,hail and sand storms,while there is less low cloud in the sky,and the percentage of the cumulostratus,cumulonimbus and cumulus fractus is just 24.9% in all of the low cloud.Meanwhile, the monthly precipitation is little,and the monthly variation of maximum temperature difference is also small.Considering the above factors,the Shahu general airport proposed site has the good weather conditions as a general airport site.%在探讨各类气象要素与通用机场选址联系的基础上,对西北地区通用机场选址气候论证中关键气象评估指标及其重要程度进

  20. 中国西北地区胃食管反流病患者临床特征的多中心研究%Clinical characteristics of patients with gastro esophageal reflux disease in several centers of Northwest China

    Institute of Scientific and Technical Information of China (English)

    高麦仓; 沈强; 王学红; 杨力; 周永宁; 张洪芳; 张蓉; 殷彩桥; 张军

    2013-01-01

    Objective To investigate the clinical characteristics of gastro esophageal reflux disease (GERD) in several endoscopy centers of Northwest China.Methods From September 2008 to September 2009,a questionnaire survey was carried out in the endoscopy centers of four hospitals in Xi'an,Xining,Lanzhou and Yinchuan.Reflux diagnostic questionnaire (RDQ) was used as diagnostic evidence.The score of symptom degree and frequency over 12 was considered as initial screening standard.One third GERD patients diagnosed by questionnaire were randomly selected.From each quadrant below the squamocolumnar junction (SCJ),one specimen was taken for pathologic examination.All the data were input into database with EpiData 3.0 software and analyzed with SPSS 15.0 software.Results A total of 12 454 eligible questionnaires were collected,1246 GERD patients were diagnosed according to RDQ,the total detection rate was 10.0%.A total of 425 cases received biopsy,the percentage of cases with upward shift of the SCJ less than 3 cm was 73.6% (313/425) and over 3 cm was 26.4 % (112/425).The pathologic results indicated the percentage of normal mucosa was 9.9% (42/425),chronic oesophagitis was 80.2% (341/425),intestinal metaplasia was 7.1% (30/425),mild atypical hyperplasia was 1.9% (8/425),severe atypical hyperplasia and squamous cell carcinoma was 0.2% (1/425) and adenocarcinoma was 0.4% (2/425).Among the GERD patients with and upward shift of SCJ less than 3 cm and over 3 cm,the incidence of chronic inflammation,intestinal metaplasia,atypical hyperplasia and neoplasm was 85.3% (267/313),1.3% (4/313),0.9% (3/313),0 and 66.0% (74/112),23.2% (26/112),5.4% (6/112),2.7% (3/112) respectively.The pathogenesis of GERD was closely related with smoking,age,gender,body mass index (BMI),alcohol intake,esophageal hiatal hernia and bile reflux.Conclusions The detection rate of GERD was high in Northwest China endoscopy centers.Age,BMI,alcohol,smoking,esophageal hiatal hernia and

  1. 西北民族地区中学生心理地位与人际交往能力的关系研究%Research on Relationship between Adolescents' Life Position and Interpersonal Communication Ability in Northwest China Minorities Region

    Institute of Scientific and Technical Information of China (English)

    杨玲; 曹莉莉; 卢婧; 安花花

    2012-01-01

    以西北民族地区甘南藏族自治州的1所多民族混合学校、1所单一少数民族学校以及兰州市所普通中学的521名中学生为被试,采用心理地位量表和中学生人际交往能力问卷,探讨不同学校类型中学生心理地位和人际交往能力的关系。结果表明:(1)西北民族地区藏汉混合学校学生的心理地位显著高于单一民族中学的学生,但与普通中学的学生之间不存在显著差异;(2)西北民族地区藏汉混合学校学生人际交往能力得分显著高于单一民族中学的学生,但与普通中学学生之间差异不显著;(3)西北民族地区中学生的心理地位与人际交往能力之间存在显著相关;(4)西北民族地区中学生的心理地位特征能够较好地预测其人际交往能力的发展水平。%Investigating one ethnic mix of school, a single minority school, and a general secondary school with 521 students in Lanzhou City distributed in Gannan Tibetan Autonomous Prefecture in Northwest China Minorities region. This study used Life Position Scale and Middle School Students Interpersonal Communication Ability Questionnaires as the research tools, discussing the relationship between the Life position and Interpersonal communication ability of the middle school students and effect in their interpersonal skills development. The results indicated: (1)In Northwest China Minorities region, Tibetan-Chinese mixed school students' life position was significantly higher than single nationality school students, but there was no significant difference between Tibetan- Chinese mixed school and general school; (2)In Northwest China Minorities region, Tibetan-Chinese mixed school students' Interpersonal communication ability was significantly higher than single nationality school students, but there was no significant difference between Tibetan-Chinese mixed school and general school; (3) There existed significant

  2. Northwest Manufacturing Initiative

    Science.gov (United States)

    2014-07-31

    warehouse. If the batch of lenses is faulty, the manufacturer wants to know ASAP in order to send Visionary Lenses a new batch of lenses. The manufacturer ...increased. • A few years ago, Nike started using pre-consumer Nike Grind – (scrap material from their manufacturing facilities) – in new ...Northwest ( in particular with firms in the manufacturing eco-system of defense supply chains). Special emphasis was placed to increase the

  3. 阿克苏市5种常见绿化树种滞尘规律%Patterns of dust retention by five common tree species for urban greening in Aksu City, Northwest China

    Institute of Scientific and Technical Information of China (English)

    阿丽亚·拜都热拉; 玉米提·哈力克; 塔依尔江·艾山; 艾克热木·吾布力; 喀哈尔·扎依木; 金华

    2014-01-01

    绿化树种在截留沙尘、降低大气颗粒污染物浓度、改善城市生态环境等方面发挥着不可替代的作用。该文选取新疆南部典型绿洲城市--阿克苏市不同功能区的绿化树种,用多重比较法对比分析了二球悬铃木(Platanus × acerifolia)、新疆杨(Populus alba var. pyramidalis)、圆冠榆(Ulmus densa)、天山梣(Fraxinus sogdiana)和垂柳(Salix babylonica)5个树种叶片平均滞尘量随时间变化及不同高度叶片的滞尘能力,探讨了阿克苏市主要绿化树种的滞尘规律,得出以下结论:不同绿化树种单位叶面积滞尘量差异显著,差距在1.15-2.17倍之间,绿化树种滞尘量随着时间延长而增加;同一树种在城市不同功能区的滞尘能力不同:工业区>交通枢纽区>居民区>清洁区;不同高度的叶片,其滞尘量在工业区和交通枢纽区差异显著:高度1m的叶片滞尘量>高度2m的叶片滞尘量>高度4m的叶片滞尘量。%Aims Air pollution poses a long-term threat to human health and life quality of urban residents. In particular, dust pollution in oasis cities of arid regions has been associated with reduced life expectancy. Trees (especially their leaves) in cities can absorb airborne particulate matter and reduce the impacts of air pollution on people and urban environment. This study examined dust retention capacity of the leaves of Platanus × acerifolia, Populus alba var. pyramidalis, Ulmus densa, Fraxinus sogdiana, and Salix babylonica in different functional areas in Aksu City, Northwest China. Our objectives were to determine that how much dust can be removed on unit leaf area basis by each of the tree species and that how the patterns of dust removal may vary with time, among different sites, and the height where leaves are positioned. Methods Dust samples were washed off the leaf surfaces and weighed by electronic scales with an accuracy of 1μg (PTX-FA-210, Polestar, Hartford, USA). Individual

  4. 祁连山天然气水合物赋存区钻孔细菌多样性%Bacterial diversity in bore holes of gas hydrate-rich deposit districts in Qilian Mountains of Northwest China

    Institute of Scientific and Technical Information of China (English)

    武淑娇; 韩路; 吕杰; 董建英; 祝有海

    2012-01-01

    分析了青海省祁连山冻土区天然气水合物赋存区DK-6钻孔的4个样品,对岩心样品进行处理提取微生物总基因组,采用PCR构建了细菌16S rDNA基因文库,4个文库包括44个OTU,其中有厚壁菌门(Firmicutes)、拟杆菌门(Bacteroidetes)、变形杆菌门(Proteobacteria)(包括α-、β-和y-变形杆菌亚群)、放线菌纲(Actinobacteria)和异常球菌-栖热菌门(Deinococcus-Thermus)5类,煤、泥岩、粉砂岩等不同岩性的微生物群落之间显示出较大的组成差异,优势菌不同.细菌菌群多样性随采集点地质环境不同而有较明显的变化,天然气水合物含量、水含量、有机质含量等环境因素对冻土区天然气水合物赋存区中细菌菌群有一定的影响.4个样品中存在的微生物大部分可以代谢有机烃类,在天然气水合物环境的特殊条件下,外界环境因素制约了微生物的种类.%In this study, four core samples were collected from the DK-6 bore holes of gas hy-drate-rich deposit districts in the permafrost zone of Qilian Mountains, Qinghai Province of North-west China, with the total bacterial genome in the samples analyzed. Four 16S rDNA gene librar-ies were created by PCR. There were 44 OTUs, including five categories, i. e. , Firmicutes, Bacteroidetes, Proteobacteria (α-, β-, and γ-Proteobacteria) , Actinobacteria, and Deinococ-cus-Thermus, in the four gene libraries. The microbial communities of different lithology showed a relatively large composition difference, and had different dominant species. Lithology played a certain decisive role to the growth of bacteria. Bore holes DK6-12 (117.5 m) and DK6-17 (161.9 m) were of mudstone, in which, Alcaligenes xylosoxidans was the dominant bacterium. K6-23 (194.6 m) was of fine sandstone, in which, a large number of Spirosoma panaciterrae was found in cloning sequences. DK6-25 (213 m) was of coal, with the highest abundance of Pantoea ananatis. Most of the microbes presented in the four

  5. Root architecture of two desert plants in central Hexi Corridor of Northwest China%河西走廊中部两种荒漠植物根系构型特征

    Institute of Scientific and Technical Information of China (English)

    单立山; 李毅; 任伟; 苏世平; 董秋莲; 耿东梅

    2013-01-01

    在河西走廊中部,采用挖掘法挖取红砂和白刺根系,应用拓扑学与分形理论分析了根系构型的特征.结果表明:2种荒漠植物根系的拓扑指数均较小,根系分支模式均近似为叉状分支结构,红砂和白刺根系具有较好的分形特征,其分形维数分别为(1.18±0.04)和(1.36±0.06);分形维数、分形丰度与根系平均连接长度均呈显著正相关.2种荒漠植物根系的平均连接长度均较大,以扩大植物的有效营养空间,从而适应干旱贫瘠的土壤环境.2种荒漠植物根系分支前的横截面积等于根系分支后的横截面积之和,验证了Leonardo da Vinci法则.对17个根系构型参数进行主成分分析,根系拓扑指数、根系连接数量、逐步分支率和根系直径4个根系构型参数能很好地表示2种荒漠植物根系构型特征.%In this study, the root systems of desert plant species Reaumuria soongorica and Nitraria tangutorum in the central Hexi Corridor of Northwest China were excavated by shovel, and the char-acteristics of the plant root architecture were analyzed by using topology and fractal theory. The root topological indices of the two desert plants were small, and the root branching patterns were herring-bone-like. The roots of the two desert plants had obvious fractal characteristics, with the fractal di-mension of R. soongorica and N. tangutorum being (1.18±0.04) and (1. 36±0.06) , respective-ly. The root fractal dimension and fractal abundance were significantly positively correlated with the root average link length. The root average link lengths of the two plants were long, which enlarged the plants' effective nutrition space, and thus, made the plants adapt to the dry and infertile soil environment. The sums of the root cross-sectional areas before and after the root bifurcation of the two desert plants were equal, which verified the principle of Leonardo da Vinci. A total of 17 pa-rameters of root architecture were analyzed

  6. Northwest Area Science

    Science.gov (United States)

    Fuentes, Tracy L.; van Heeswijk, Marijke; Grossman, Eric E.

    2010-01-01

    Northwest Area Facts * Population about 12 million * 43 federally recognized Tribes * Hydropower provides about two-thirds of electricity supply * 78 federally listed threatened and endangered species * 12 active or potentially active volcanoes * Columbia River system drains more than 260,000 square miles, an area about the size of Texas * More than 175 square miles covered by glaciers * More than 900 miles of Pacific Ocean coastline * More than 2,300 miles of greater Puget Sound coastline * Some forests store more carbon per unit area than any other area in the world, including the tropics * 51 percent federal lands * Significant lead, zinc, silver, and phosphate deposits

  7. PetroChina Sees Gas Pipeline Profit in Four Years

    Institute of Scientific and Technical Information of China (English)

    Xiao Lu

    2002-01-01

    @@ Sebei-Xining- Lanzhou pipeline put into operation PetroChina, the nation's largest gas producer,recently said that the US$280-million gas pipeline in Northwest China would generate profits within four years.

  8. Preliminary survey of the Helvellaceae from Xinjiang, China

    Institute of Scientific and Technical Information of China (English)

    ZHUANG Wen-ying

    2004-01-01

    @@ Xinjiang is in the northwest of China. It occupies more than 1/7 of the China mainland territory (Fig. 1). The area is covered with deserts, grasslands, conifer forests, broadleaf trees, and shrubs.

  9. Northwest Climate Risk Assessment

    Science.gov (United States)

    Mote, P.; Dalton, M. M.; Snover, A. K.

    2012-12-01

    As part of the US National Climate Assessment, the Northwest region undertook a process of climate risk assessment. This process included an expert evaluation of previously identified impacts, their likelihoods, and consequences, and engaged experts from both academia and natural resource management practice (federal, tribal, state, local, private, and non-profit) in a workshop setting. An important input was a list of 11 risks compiled by state agencies in Oregon and similar adaptation efforts in Washington. By considering jointly the likelihoods, consequences, and adaptive capacity, participants arrived at an approximately ranked list of risks which was further assessed and prioritized through a series of risk scoring exercises to arrive at the top three climate risks facing the Northwest: 1) changes in amount and timing of streamflow related to snowmelt, causing far-reaching ecological and socioeconomic consequences; 2) coastal erosion and inundation, and changing ocean acidity, combined with low adaptive capacity in the coastal zone to create large risks; and 3) the combined effects of wildfire, insect outbreaks, and diseases will cause large areas of forest mortality and long-term transformation of forest landscapes.

  10. 基于生物气候条件的西北地区城市开放空间设计——以白银金鱼公园全民健身广场设计为例%Urban Open Space Design in Northwest China Based on the Bio-climatic Conditions: Taking Baiyin Jingyu Park Healthy Square as An Example

    Institute of Scientific and Technical Information of China (English)

    毕晓莉; 刘起

    2011-01-01

    从西北地区的广场设计面临的现妾问题出发,从地域气候角度分析了现象下的内在成因.从而以生物气候的视野提出应对的西北地区域市开放空间设计策略.最后.以白银金鱼公园全民健身广场为实证案例,提出了基于生物气候条件的设计系列方法.%Firstly, the paper analyzes the present urban open space design method and its existing problems in the northwest China. Farther more, a reasonable strategy based on bio-climatic conditions is given to urban open space. At last, a series of method is put forward by taking Baiyin Jingyu Park Healthy Square as an example.

  11. Global warming: A Northwest perspective

    Energy Technology Data Exchange (ETDEWEB)

    Scott, M.J.; Counts, C.A. (eds.)

    1990-02-01

    The Northwest Power Planning Council convened a symposium in Olympia, Washington, on the subject of global climate change ( the greenhouse effect'') and its potential for affecting the Pacific Northwest. The symposium was organized in response to a need by the Power Council to understand global climate change and its potential impacts on resource planning and fish and wildlife planning for the region, as well as a need to understand national policy developing toward climate change and the Pacific Northwest's role in it. 40 figs., 15 tabs.

  12. Global warming: A Northwest perspective

    Energy Technology Data Exchange (ETDEWEB)

    Scott, M.J.; Counts, C.A. (eds.)

    1990-02-01

    The Northwest Power Planning Council convened a symposium in Olympia, Washington, on the subject of global climate change ( the greenhouse effect'') and its potential for affecting the Pacific Northwest. The symposium was organized in response to a need by the Power Council to understand global climate change and its potential impacts on resource planning and fish and wildlife planning for the region, as well as a need to understand national policy developing toward climate change and the Pacific Northwest's role in it. 40 figs., 15 tabs.

  13. Recommendations about Extension of Ceratoides Growing in the Northwest China%关于在西北地区大力推广种植驼绒藜的建议

    Institute of Scientific and Technical Information of China (English)

    李敬忠; 阿拉塔

    2012-01-01

    and wind erosion, easy cultivation ;(2) high value of forage:rich nutrition, palatability, fast growth, high forage yield; (3)ecological benefits: multiply rapidly, developed root system,windbreak and sand, soil and water conservation,long growing season. It's a pioneer plant for soil improvement and afforestation. This shows that developing Ceratoides in most areas of northwest China is of great significance for restoring grassland vegetation, promoting the sustainable development of agriculture and improving the ecological, economic and social benefits. In particularly,the new cuhivar "Ceratoides arborescens (Losinsk.)Tsien et C. G. Ma cv. Keerqinxing" has high aboveground biomass and good ecological effects. It should be planted according to local conditions selection,planning,firstly to create Ceratoides seed base, and then further to study the fruit processing and seed longevity technical measures, and continue to foster new superior breeds.

  14. Community structure and its relationship with environmental factors in zooplankton in Jinghe River system in Northwest China%泾河水系浮游动物群落结构及其与环境因子的关系

    Institute of Scientific and Technical Information of China (English)

    白海锋; 李丽娟; 项珍龙; 王博涵; 殷旭旺; 徐宗学; 沈红保; 问思恩

    2015-01-01

    为了解渭河流域最大支流———泾河水系的浮游动物群落结构特征及水质状况,于2012年10月对该水系15个采样断面的浮游动物群落和水环境理化特征进行了调查,并运用Canoco 4.5软件对浮游动物群落与环境因子进行典范对应分析。结果表明:泾河水系浮游动物种类共有28属42种,其中轮虫占主导,原生动物和桡足类次之,分别占种类总数的85.72%、7.14%和7.14%;游动物密度为0.9~36.0 ind./L,平均值为8.5 ind./L,生物量为0.0011~0.0425 mg/L,平均值为0.0097 mg/L;浮游动物优势种有8种;Shannon-Weiner多样性指数(H)平均值为2.38, Pielou均匀度指数(J)平均值为0.75;浮游动物密度聚类分析结果显示,泾河水系各断面浮游动物可分为4大类群;典范对应分析( CCA)结果显示,驱动泾河水系浮游动物群落结构形成的水环境因子为水温、海拔和河宽。基于浮游动物群落结构特征,根据物种多样性指数对泾河水系水质状况进行评价,结果显示,泾河水系水质属于β-中污染,浮游动物群落结构趋于简单化,需要加强流域生态建设及污染治理。%The community structure of zooplankton and characteristics of environment were investigated in 15 sam-pling sites in the Jinghe River system, as the largest tributary of the Weihe River basin, Northwest China, in au-tumn of 2012, and analyzed by canonical correspondence analysis using Canoco 4. 5 software. It was found that there were 42 zooplankton species belonging to 28 genera, with dominant rotifers accounting for 85. 72% in the spe-cies composition, followed by protozoa (7. 14%) and copepod (7. 14%). The zooplankton had a density of 0. 9-36. 0 ind. /L, with an average of 8. 5 ind. /L, and biomass of 0. 001 1-0. 042 5 mg/L, with an average biomass of 0. 009 7 mg/L. There were eight dominant species of zooplankton in Jinghe River system, with average Shannon-Weiner species diversity index( H) of 2. 38 and

  15. 本土营造--西北地区低碳生态乡镇的低技术策略%LOCAL CONSTRUCTION--Low technology strategy of Low-carbon eco-towns in Northwest China

    Institute of Scientific and Technical Information of China (English)

    段德罡; 黄梅; 穆钧

    2013-01-01

    针对当前我国低碳生态城镇实践过分依赖“高技术、高投入”而难以实施的问题,结合西北地区乡镇发展的现实困境,本文提出西北地区乡镇低碳生态的理想路径为:探索一条具有地域适宜性的“低技术”策略,进而通过对西北地区乡镇碳排放特征的分析,提出加强对乡镇建设性碳排放的控制是西北地区乡镇实现低碳生态目标的关键。最后结合西北地区乡镇的地域特质,依托西安建筑科技大学在地域生态建筑与现代生土材料科学等领域的研究基础,提出:本土营造是降低乡镇建设性碳排放的有效途径,并提出其在规划与管理中的推广、应用策略。%Over-reliance on"high-tech and high investment"practice in current low-carbon eco-towns is difficult for implement which has become a difficult question.Combine the practical difficulties of towns’ development in Northwest, this paper presents a ideal path for low-carbon eco-towns practice:Explore a geographical suitability with"low technology"strategy, and then through the analysis for carbon emission characteristics of towns in the Northwest region, proposes that strengthen the control ing for carbon emissions of towns’ construction is the key to achieve low-carbon eco goals for towns in Northwest.Combined with the geographical characteristics of Northwest towns,and relying on the Xi'an University of Architecture and Technology University’s research base in the area of ecological architecture and modern adobe materials science ,final y propose a conclusion that Local construction is a effective way to reduce carbon emissions of towns’ construction ,at the same time , putting forward applied and conducive strategy in the planning and management.

  16. Two Stratigraphic Concerns on the Central and Northern Tianshan Tectonic Complex, Northwest China%与天山造山带大地构造解释相关的两个地层问题

    Institute of Scientific and Technical Information of China (English)

    廖卓庭; 陈中强; 刘陆军

    2011-01-01

    Two tectonostratigraphic concerns on the Late Paleozoic Tianshan tectonic complex were addressed in this study: (1) the stratigraphic succession of the Bayingou ophilite melange and (2) the timing of tectonic accretion of the Siberian craton in the Aiweiergou area by integrating the relevant data of stratigraphy, palaeontology, tectonopaleogeography and tectonopaleobiogeography. In the Bayinggou area, the detailed paleontological studies have rejected the presence of the brachiopod Gigantoproductus fauna of Early Carboniferous age in the Anjihai Formation. In contrast, the brachiopod assemblage suggests a Late Devonian age for the Anhinhai Formation. Integration of fossil assemblages and paleogeographical and paleobiogeographical settings indicates that the Bayingou area belongs to the eastern Junggar tectonic complex rather than the central-south Tianshan complex. The latter is characterized by the presence of Gigantoproductus fauna during the Early Carboniferous. Thus, the Bayinggou ophiolite m lange is late Devonian in age. The top of the stratal package of the ophiolite m lange should be re-assigned to the Taoxigou Group rather than the Keguqingshan Formation in view of lithological features and tectonostratigraphic provinces. The former was established to accommodate the stratal package of volcanics, conglomerates and mudstone in the Junggar block, while the latter is poorly defined for the conglomerates exposed in the western Tianshan areas. Accordingly, the Bayinggou ophiolite m lange succession comprises the late Devonian Anjihai Formation, the Carboniferous Bayinggou and Shadawang Formations, and the Taoxigou Group of Early Permian age. Xiao et al. (2008) figured an outcrop section showing a distinct angular unconformity between the Permian turbidite and the Middle-Upper Triassic red beds at the Aiweiergou area, about 110 km south of Urumqi, the capital city of Xinjiang Province,northwest China. These authors considered that this unconformity indicates the

  17. 南海西北部陆架区沿岸流和上升流对中华哲水蚤分布的影响%Effects of coastal current and upwelling on the distributions of Calanus sinicus on the northwest continental shelf of the South China Sea

    Institute of Scientific and Technical Information of China (English)

    尹健强; 黄良民; 李开枝; 练树民; 李超伦; 张建林

    2013-01-01

    Calanus sinicus is a planktonic copepod with wide geographical distribution on the continental shelf of the northwest Pacific It plays an important role in marine system. Four cruises were conducted from July 2006 to October 2007 in order to understand the seasonal and horizontal variations with the influences of monsoon, ocean cur-rent and temperature on its distributions on the northwest continental shelf of the South China Sea. The diel vertical migration (DVM) of C. sinicus was studied at one station located in the southeast of Hainan Island during summer. The results showed that the distribution of C. sinicus abundance varied seasonally and regionally. The mean of C. sinicus abundance was high with 23. 30±77. 78 ind. /m3 in spring, and decreased to 13. 74 + 45.10 ind. /m3 in summer. It disappeared in autumn and did not enter into the study area during the investigated period in winter. The surveyed area was divided into three sub-regions in order to further analyze the regional difference, including the east inshore waters of Leizhou Peninsula, the east inshore waters of Hainan Island and and the offshore waters from Leizhou Peninsula to Hainan Island. The average abundance of C. sinicus within the inshore waters of Leizhou Peninsula was reached to be 115. 63 (±145. 93) and 68. 12 (±84. 00) ind/m3 in spring and summer, respectively, which was higher than those of the inshore Hainan Island and the offshore from Leizhou Peninsula to Hainan Island. The behavior of C. sinicus DVM was not found in the upwelling area in summer. C. sinicus seemed to be mostly habited in the bottom layer in order to avoid the damage of high temperature in the surface layer. The study area is the seasonal distribution zone of C. sinicus. Our findings suggested that C. sinicus was transported from the East China Sea to the northwest continental shelf of South China Sea by the Guangdong Coastal Current, which was driven by the northeast monsoon in winter and spring. The presence of a

  18. BPA Committed to Northwest Values

    Energy Technology Data Exchange (ETDEWEB)

    None

    2010-09-01

    The Columbia River has been called the “crown jewel” of the Pacific Northwest. There is no question it is among the region’s greatest assets — supplying low-cost clean hydropower, making deserts bloom thanks to irrigation and providing navigation, recreation and a home for many species of fish and wildlife. The Bonneville Power Administration is proud to be a steward of this great resource. Our mission is to serve the people and environment of the Pacific Northwest. We sell wholesale power from Grand Coulee Dam and 30 other Northwest federal dams to Northwest utilities, including public utility districts, rural electric cooperatives and municipal utility departments, as well as investor-owned utilities. We operate three-fourths of the region’s high voltage transmission system that delivers that power. But, as a federal agency, we are not just a power marketer. We have public responsibilities that include, among many, promoting energy efficiency, facilitating development of renewable power, protecting fish and wildlife affected by hydro development, honoring treaty obligations to tribes and promoting a reliable energy future through collaboration and partnerships. This document describes our responsibilities to citizens in the Pacific Northwest.

  19. Dispatch Operation Model Adaptable to Development of “Three Type” Grid in Northwest China%适应西北“三型”电网发展形势下的调度运行模式

    Institute of Scientific and Technical Information of China (English)

    王鹏; 彭明侨; 王世杰; 张小奇; 贺元康

    2011-01-01

    Given that the current dispatch operation model is not adaptive to the development of the "Three type" northwest grid, this paper expounds the frame requirements of the new operation model in terms of general goals such as balanced coordinating of the safety operation within the grid, trans -regional power delivery, wind power accommodation, utilization of the cascade reservoirs, and "Fair, Open and Just" dispatch. Focus is given on task assignments and coordination of the power control goals between the regional power dispatch center and provincial dispatch centers and three new dispatch operation options are proposed with the advantages, disadvantages and applicability of each option given in a bid to explore and determine a new dispatch evaluation model for the northwest grid.%以西北电网现行调度模式与“三型”电网发展的不适应性为出发点,阐述了新调度运行模式在统筹协调安全运行、跨区外送、风电消纳、水库运用、“三公”调度等综合目标方面的框架要求,重点针对网、省调度间功率控制目标的任务分解与协作配合的问题,提出了3种可供参考的新调度运行模式,并对比分析了各自的优劣性、适用性,为西北电网新调度考核模式的确立提供了探索研究.

  20. Irradiation of northwest agricultural products

    Science.gov (United States)

    Eakin, D. E.; Tingey, G. I.

    1985-02-01

    Irradiation of food for disinfestation and preservation is increasing in importance because of increasing restrictions on various chemical treatments. Irradiation treatment is of particular interest in the Northwest because of a growing supply of agricultural products and the need to develop new export markets. Several products have, or could potentially have, significant export markets if stringent insect ocntrol procedures are developed and followed. Due to the recognized potential benefits of irradiation, this program was conducted to evaluate the benefits of using irradiation on Northwest agricultural products. Commodities currently included in the program are cherries, apples, asparagus, spices, hay, and hides.

  1. Zr-in-rutile thermometry in HP/UHT granulite in the Bashiwake area of the South Altun and its geological implications%南阿尔金巴什瓦克高压/超高温麻粒岩中金红石Zr温度计及其地质意义

    Institute of Scientific and Technical Information of China (English)

    于胜尧; 张建新; 宫江华

    2011-01-01

    The trace element content in rutile was analyzed by both electron microprobe (EMP) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for HP granulite in the Bashiwake area of the South Altun HP-UHP metamorphic belt. Results indicate that Zr content in rutile from HP granulite measured by EMP coincides with these measured by LA-ICP-MS within experimental error. Zr-in-rutile thermometry of Thomkins et aL (2007) yields temperatures that agree with previous results by traditional thermometry calibrations, and thus it is more suitable for temperature estimation for HP granulite in Bashiwake area, whereas the other two calibrations developed by Zack et al. (2004) and Watson et al. (2006) give systematically higher or lower temperatures. Calculated Zr-in-rutile temperatures in fresh HP granulite range from 890 ℃ to 962 ℃ at 2.0 GPa, representing the peak metamorphic temperature of high pressure granulite Zr-in-rutile temperatures in retrogressed HP granulite yielded temperatures between 764 ( and 822 ℃. These results further show that HP granulites in the Bashiwake area of the South Altun HP-UHP metamorphic belt experienced peak conditionis at ultrahigh temperature and high pressure, followed by medium temperature granulite facies conditions related to retrogression.%文中对南阿尔金高压-超高压变质带巴什瓦克地区的高压麻粒岩中的金红石进行了电子探针和薄片原位LA-ICP-MS微量元素分析.教据结果显示,运用电子探针和薄片原位LA-ICP-MS两种实验方法测得巴什瓦克高压麻粒岩中的金红石Zr含量在误差范围内基本一致.对比研究表明,经过压力校正的Thomkins等(2007)的金红石Zr含量温度计算公式更适合本区高压麻粒岩温度的计算,而采用Zack等(2004)和Watson等(2006)的公式计算的温度分别比前人通过传统温度计获得的温度结果偏高和偏低.按照Thomkins等(2007)的金红石Zr含量温度计算公式,以压力为2 GPa

  2. Pacific Northwest Salmon Habitat Project Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In the Pacific Northwest Salmon Habitat Project Database Across the Pacific Northwest, both public and private agents are working to improve riverine habitat for a...

  3. Hispanics in the Pacific Northwest.

    Science.gov (United States)

    Cook, Annabel Kirschner

    Sources of diversity in the Pacific Northwest's Spanish origin population, up 79.7% since 1970, was the subject of research based on 1980 Census data. Census information for Whites and Hispanics from metropolitan and nonmetropolitan counties with 400 or more persons of Spanish origin was compared on the basis of age, family/household structure,…

  4. Solar 78 Northwest conference proceedings

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-01-01

    Thirty eight papers are included. One was abstracted previously. Separate entries were prepared for thirty-seven. Also included are the conference evaluation summary, Pacific Northwest Solar Energy Association organization information, lists of commercial and non-commercial exhibitors, speakers and stearing committee members, and attendees. (MHR)

  5. [Dynamic monitoring of ecological environment in loess hilly and gully region of Loess Plateau based on remote sensing: A case study on Fuxian County in Shaanxi Province. Northwest China].

    Science.gov (United States)

    Li, Fen-ling; Chang, Qin-rui; Shen, Jian; Liu, Jing

    2015-12-01

    Based on the principal component analysis (PCA), four ecological evaluation indicators including vegetation index, wet index, land surface temperature and soil index were combined to evaluate the ecological environment quality of Fuxian County in hilly and gully area of Loess Plateau from year 1995 to 2014. The results showed that the RSEI integrated RS and PCA method could reveal regional ecological changes objectively and quantitatively. The level of overall regional ecological status in Fuxian County was good with a high vegetation fraction and rich biodiversity. The synthetical ecological environment quality index increased from 3.17 to 3.53 indicating the ecological environment had been improved greatly in recent 20 years. The area with best ecological environment quality was located in Niuwu town. The magnitude of change increased progressively from northwest to southeast, and the biggest change occurred in Jiaodao and Nandaode towns. From 1995 to 2014, the areas with decreased and increased ecological environment quality were 16.7% and 42.7% of the study area, respectively, and the improved regions were mainly distributed in plateau and hilly area in the center, rocky low mountainous area in northeast and the Ziwuling Nature Reserve area in southwest of the county.

  6. Northwest Ohio Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Moyer, Kevin

    2015-03-04

    Improvement Districts or ESIDs and what is nationally known as Property Assessed Clean Energy or PACE districts and PACE financing. The project methodology followed the identify, develop, implement, monitor and measure format. These districts began in Toledo and adjoining areas and are expanding to TLCPA’s 28 county financing agency geographic footprint. What began as the Toledo Ohio Advanced Energy Improvement Corporation is now doing business as the Northwest Ohio Advanced Energy Improvement District recognizing it expansion into creating and financing other districts in NW Ohio. The program has been sought out as an advisor by major communities and states in the process of developing similar legislation and programs and has become one of the largest most successful PACE energy improvement and financing districts in the US. The program and the energy district focused on transforming energy use, delivery, conservation and renewable energy as “options of first choice”. The significant energy savings paid for many of the improvements and created a financially viable program well beyond the grant period. The program has become a model within the State of Ohio and Nationally on how to implement and finance projects in broad energy districts including how to evolve and integrate several financing methodologies. It is a unique utilization of revolving loan funds and energy bond pooling with revenue backing primarily from energy improvement special assessments on commercial properties along with some power purchase agreement (PPA) and loan agreement revenue. The program has also incorporated Qualified Energy Conservation Bonds, State of Ohio Energy Loans (SEP), utility rebates, solar and renewable energy certificates, renewable tax incentives and grants, and owner funded equity as additional program leverage and funding. Other keys to this success have been a continual simplification and refinement of the application and documentation process to make funding available easily

  7. A Research on Translation Textbooks in EFL Programme Nine Colleges and Universities in Northwest China as A Case%英语专业翻译教材研究与开发——西北九所高校教材案例研究

    Institute of Scientific and Technical Information of China (English)

    陈琪

    2012-01-01

    Translation courses are offered to students studying in EFL programmes in almost 1000 col- leges and universities in China in spite of the fact that some insititutions have been authorized to establish BTI and MTI programmes. With this in mind, the present thesis, based on an empirical research on trans- lation textbooks and needs assessment in 9 colleges and universities in 2 provinces and 2 autonomous re- gions in the north--west of China, attempts to reveal the conflicting relationship and achieve the balance between College English Curriculum Requirements promulgated by the Ministry of Education(revised ver- sion in 2007), teaching philosophy, and textbooks development, and finally by drawing insights from Cun- ningsworth's guideline for coursbook assess--ment, the paper proposes to design a textbook from a com- paratively new perspective in the hope that it can shed light on translation textbook compilation for teach- ers and learners who work and study in EFL programmes at colleges and universities in China.%2006年至今,我国大约有31所大学获批翻译专业本科(BTI)和翻译专业硕士(MTI)的办学资格;但是,据不完全统计,我国仍然有将近1000所大学英语专业在高年级开设翻译课程。有鉴于此,本文对西北地区甘肃和青海两省、宁夏回族自治区和新疆维吾尔自治区的9所大学英语专业翻译教材、学习者需求和翻译公司的人才需求展开实证研究,旨在挖掘教育部对英语专业翻译课程的要求、教学理念以及教学材料选择和应用等三者之间的矛盾关系,并以坎宁斯沃思的指导方针(guideline)为理据,为翻译教材的评估和编撰提供了特定标准,以期在教学目标、教学理念和教学材料三者之间寻求平衡。

  8. Study on forecast method of thunderstorm based on weather types and physical diagnostic analysis in eastern region of Northwest China%基于天气分型和物理量诊断西北地区东部雷暴预报方法研究

    Institute of Scientific and Technical Information of China (English)

    孔德兵; 汪结华; 尚可政; 叶伟; 赵文婧; 王式功; 杨流贵

    2016-01-01

    利用2008—2013年西北地区东部169个气象观测站的天气实况资料和NCEP/NCAR 1°×1°再分析资料计算的对流参数对西北地区东部雷暴日进行了天气分型,并应用分型统计的参数阈值对2013年西北地区东部雷暴日进行了试预报。结果表明:2008—2013年西北地区东部雷暴日集中出现在5—9月,占雷暴总日数的85.9%;雷暴日发生的天气形势可分为低涡型、低槽型、西北气流型和西南气流型4种。引入天气型强度指数,研究4种雷暴天气型的自动识别方法,通过天气分型检验表明,天气型自动识别方法可准确的识别雷暴发生的天气形势,且漏报较少。在天气型识别的基础上,进一步进行雷暴物理量诊断表明,消空效果明显。2008—2012年西北地区东部雷暴日回代预报的TS评分为54.1%,漏报雷暴日为4 d;2013年雷暴日试预报的TS评分为51.8%,漏报雷暴日为10 d;雷暴日回代预报与试预报的TS评分均超过气候概率,预报效果较理想,可为西北地区东部雷暴天气预报研究提供参考。%Based on the meteorological observations from 169 meteorological stations and the NCEP/NCAR (Na-tional Centers for Environmental Prediction/National Center for Atmospheric Research)reanalysis data with reso-lution of 1°×1°in the eastern region of Northwest China from 2008 to 2013,weather types of thunderstorm days were classified using calculated convective parameters,and the operational forecast of thunderstorm in 20 1 3 was carried out according to parameter thresholds of different weather types.The results show that thunderstorm days mostly occur from May to September and account for 85.9%of the total thunderstorm days during this study peri-od.There are four weather types of thunderstorm days,including the lower vortex type,the lower trough type,the northwesterly flow type,and the southwesterly flow type.The automatic identification method of

  9. 中国西北地区生态环境的演变及治理策略%The Development and Administration of Organisms' Habits Environment in Northwest China

    Institute of Scientific and Technical Information of China (English)

    刘露; 苏睿先; 陈可馨

    2001-01-01

    西北地区是我国生态环境最脆弱的地区.为了顺利发展西北地区经济,探讨了西北地区生态环境的演变,客观分析了西北生态逐步恶化的原因,进而提出了开发西北必须以生态建设为重点的可持续发展战略.%The organisms' habits environment is the most fragile in thenorth west of China. Through introducing the development and the changes of the organi sms' habits environment, the article submits the sustainable development methods which is the center on the organisms' habits construction to develop the Northw est.

  10. 西北地区农村小学生贫血现状及影响因素研究%Anemia in Rural China' s Elementary Schools:Prevalence and Correlates in Northwest Area

    Institute of Scientific and Technical Information of China (English)

    蔡颖萍

    2013-01-01

    The goal of this paper was to measure anemia prevalence and identify factors that correlate with anemia among school-aged children in rural areas,provide a scientific basis for effective prevention and treatment.[Method] The data set covered three provinces in northwest area.We detected hemoglobin of the sample pupils randomly chosen from the 3~-6~ grade of 305 rural elementary schools in 26 poor counties,and carried out questionnaires among them.[Result]25.24% of the pupils had anemia,most of them were girl and the lower grade students.The multiple-regression revealed that the eating habits and family condition had certain impact on their anemia.[Conclusion] Anemia is still a serious problem of rural pupils.Improving diet conditions,providing balanced meals,enhancing the knowledge of the principals,teachers and parents about anemia and the importance of students' nutritional status and health contribute to the prevention and treatment of anemia of rural pupils.%[目的]了解西北地区农村小学生贫血患病率及其影响因素,为制定有效的防治策略提供科学依据.[方法]选取西北地区3个省26个贫困县的305所农村小学的三至六年级学生作为研究对象,通过随机抽样的方法对学生进行血红蛋白测定以及问卷调查.[结果]西北地区农村小学生贫血患病率高达25.24%,女生与低年级学生是患病率较高的人群.通过多元回归结果显示,学生饮食习惯与家庭情况对学生贫血状况有一定程度的影响.[结论]西北地区农村小学生贫血问题仍很严重,改善饮食条件、平衡膳食,提高校长、班主任及家长对学生贫血的认识以及对学生营养状况与身体健康的重视有助于农村小学生贫血的防治.

  11. 中国西北地区披碱草属植物所带内生真菌的培养特征%Characteristic of asexual endophytes isolated from Elymus species in northwest China

    Institute of Scientific and Technical Information of China (English)

    宋辉; 南志标; 田沛

    2015-01-01

    内生真菌与植物所形成的共生体普遍存在于冷季禾草中,共生体有利于提高宿主植物的生物和非生物抗性。虽然目前研究者们已对禾草内生真菌做了大量的研究,但是尚未发现对分布于中国西北地区披碱草属植物无性世代 Neotyphodium 内生真菌培养特征的研究。本研究从中国西北地区分离出15株来自不同地理种群披碱草属植物无性世代 Neotyphodium 内生真菌。通过分离培养,测定了这15株无性世代 Neotyphodium 内生真菌的菌落生长速度,结果显示,这15株无性世代 Neotyphodium 内生真菌菌落的平均生长速度为(0.41~0.85)mm/d,且生长速度与海拔具有相关性。分布在海拔低于3000 m 的无性世代 Neotyphodium 内生真菌的菌落生长速度比生长于海拔高于3000 m 菌落的生长速度快。观察菌落发现,分布在海拔高于3000 m 的菌落正面特征较为一致,而分布在海拔低于3000 m 的菌落正面特征出现不同。另外,通过多基因联合建树发现,分布在海拔高于3000 m 的无性世代 Neotyphodium 内生真菌聚在一个分支,而分布在海拔低于3000 m 的无性世代 Neotyphodium 内生真菌呈现星状分布。由于目前尚未对中国西北地区披碱草属植物无性世代 Neotyphodium 内生真菌命名。因此,希望本研究结果能为该菌的命名提供理论依据。%Forage grasses (Poaceae)often harbour endophytes belonging to the Neotyphodium and Epichlo(Clavicipitaceae,Ascomycota)genera.Neotyphodium endophytes,the asexual state of Epichlospecies,helps to protect cool-season grasses against biotic and abiotic stresses including drought,disease,herbivory and para-sitism and enhance aboveground and belowground vegetative and reproductive growth.There is little informa-tion on colonial diversity of asexual endophytes isolated from Elymus species in northwest Chinese.In the present study,different geographic

  12. Multi-timescale Drought Variations based on standardized precipitation index in China during past 52 years

    Science.gov (United States)

    Wang, su ping; jie Zhang, cun; Li, yao hui; Feng, jianying; Wang, jinsong

    2016-04-01

    Based on daily precipitation data from 566 weather stations during 1960 to 2011 , the multi-timescale variations of drought in China were analyzed by using Standardized Precipitation Index. The results showed that there existed a northeast to southwest drought belt in China in recent 52 years. The climate in Northeast China, North China, eastern Inner Mongolia, east of Northwest China and Southwest China was becoming dry. Meanwhile it became significant wetter in Northern Xinjiang, central Qinghai and north central Tibet. The drought trend in North China mainly happened in summer, and drought in Northeast and Southwest occurred in summer and autumn, in the middle and lower reaches of the Yangtze River and the east part of Northwest it was mainly in spring and autumn. In Northeast China, the drought days in 1970s and 2000 - 2011 were more than other decades, and it were fewer in 1960s. In North China and the east of Northwest China, the driest decade was 1990s, and it was wetter from 1960s to 1980s. Southwest China experienced more droughts after 2000, and fewer in 1960s and 1970s. In the middle and lower reaches of Yangtze River .drought days were more in 1960s and after 2000, and fewer in 1980s. In 1960s, the high occurrence frequency of drought was in the west and middle of Northwest China and the middle and lower reaches of Yangtze River. In 1970s,the droughts frequently occurred in Northeast and the west of Northwest. In 1980s,drought events mainly took place in North China, Huang Huai plain, the west and middle part of inner Mongolia and east of Southwest respectively. In 1990s,the areas with high occurrence were transferred to the southeast of Northwest, North China, and Huang Huai, Jiang Huai, Jiang Han plain. After 2000, drought frequently occurred in Northeast, the middle and lower reaches of Yangtze River and east part of Inner Mongolia, Northwest and Southwest China.

  13. Degradation characteristics, patterns, and processes of lakeside wetland in Napahai of northwest Yunnan Plateau, Southwest China%滇西北高原纳帕海湖滨湿地退化特征、规律与过程

    Institute of Scientific and Technical Information of China (English)

    尚文; 杨永兴

    2012-01-01

    采用双向指示种分析(TWINSPAN)和典范对应分析(CCA)方法,研究了滇西北高原纳帕海湖滨湿地退化特征、规律与过程.结果表明:纳帕海湖滨湿地植物群落可以划分为4个群丛,群落演替规律为水生植物群落→沼泽植物群落→沼泽化草甸植物群落→草甸植物群落.随植物群落演替,群落盖度、密度、多样性指数、物种丰富度和地上生物量均增大,群落高度减小;植物水分生态型演替规律为水生植物→沼生植物→湿生植物→中生植物.随群落演替,湿地水体矿化度、硬度和碱度均降低,氨氮和总磷含量升高,总氮和硝态氮含量变化不明显;土壤pH、有机质和全氮含量逐渐降低,全磷和全钾含量逐渐升高,速效氮和速效磷含量先增大后减小.CCA分析表明,群落结构和物种组成主要受水分梯度影响,土壤pH、全磷和湿地水的总氮、氨氮对湿地植物物种分布和群落演替影响显著.%Two-way indicator species analysis (TWINSPAN) and canonical correspondence analysis (CCA) were employed to analyze the degradation characteristics, patterns, and processes of lakeside wetland in Napahai of northwest Yunnan Plateau. The plant communities in the lakeside wetland could be classified into four associations, according to the TWINSPAN results. The succession patterns of the plant community were represented by aquatic plant community→swamp plant community→swamp meadow plant community→meadow plant community. During die processes of succession, the plant community coverage, density, Shannon diversity index, species richness, and plant aboveground biomass increased, whereas the community height decreased. The succession of the plant hydro-ecotypes followed the sequence of aquatic→helophyte→hygrophyte→ meso-phyte. With the succession of the plant community, the wetland water quality indices salinity, alkalinity, and hardness decreased but ammonium nitrogen and total phosphorus

  14. 西北某部官兵第三磨牙阻生齿与患龋流行状况调查分析%A Survey on Impacted Teeth and Dental Caries Status of Military Persons in Northwest of China

    Institute of Scientific and Technical Information of China (English)

    王军; 李广文; 吕波涛; 齐志远; 张燕; 李刚

    2012-01-01

    Objective The aim of this study was to survey impacted teeth and dental caries to analysis epidemiology factors among the military persons in northwest of China. Methods Based on WHO methodology of oral health survey (1987) ,data of 643 military persons, who were collected from one camp in northwest of China by cluster sampling. The information was analyzed with software such as Foxpro 6.0 and SPSS 11.5. Results Data of 643 military persons were collected from the same area. The survey results showed that the index of impacted teeth among PLA was 28.3% ,D(decayed) was 0.21 and DMF( decayed,missing and filled) was 0.52. Conclusion Impacted teeth and dental caries epidemiology factors might affect oral health under military environment. We must put prevention policy in the first place. Throughout oral health education, regular oral health checking and treatment,all the problems mentioned above may be solved well partly.%目的 了解第三磨牙阻生齿与龋病在我军人员中的流行情况,为我军开展军人口腔疾病医疗保健提供依据.方法 采用世界卫生组织1987年版口腔健康调查基本方法和标准器材,并根据我军实际情况需要设定了第三磨牙阻生齿与龋病调查项目,采用整群抽样的方法分别对西北某部官兵进行口腔健康调查.获得数据利用FoxPro6.0软件建立数据库,SPSS11.5软件进行统计描述分析.结果 共调查643人,结果表明该部现役人员第三磨牙阻生齿指数为28.3%,龋均为0.21,龋失补齿指数为0.52.结论 该部官兵第三磨牙阻生齿发生率比较大,需要大量预防和治疗.而龋病患病率比较平稳,龋病大部分处于早期阶段.口腔健康保健、定期口腔检查和早期口腔疾病治疗对预防官兵口腔疾病极其重要.

  15. 西北地区三级医院不同胎龄新生儿呼吸窘迫综合征疾病特点和防治状况研究%Clinical features, prevention and treatment of respiratory distress syndrome in neonates of different gestational ages in tertiary hospitals in Northwest China

    Institute of Scientific and Technical Information of China (English)

    付惠玲; 刘俐; 张娟; 王全丽

    2015-01-01

    目的:调查西北地区三级医院不同胎龄新生儿呼吸窘迫综合征(RDS)的疾病特点和防治状况,为西北地区RDS的防治提供依据。方法将2011年1月至12月西北三省12家三级医院诊断为RDS的新生儿440例分为早期早产儿组(胎龄<34周,n=247)、晚期早产儿组(胎龄34~36+6周,n=131)和足月儿组(胎龄≥37周,n=62),收集各组患儿发病基本情况、围产因素、防治情况、并发症及预后等进行回顾性分析。结果早期早产儿组多胎率最高;两个早产儿组胎膜早破发生率高于足月儿组;足月儿组无宫缩剖宫产率高于两个早产儿组。产前激素应用率以早期早产儿组最高;早期早产儿组肺表面活性物质(PS)的使用率及首次应用时间均高于其余两组(P<0.05);足月儿组产房开展复苏率低于其余两组(P<0.05)。早期早产儿组动脉导管未闭(PDA)及颅内出血的发生率均为最高;RDS治愈率以足月儿组最高(78.2%),晚期早产儿组次之(58.6%),早期早产儿组最低(42.9%)(P<0.05)。结论西北地区不同胎龄RDS患儿在围产期因素、产前预防、PS治疗、并发症及预后等方面有明显不同。%ObjectiveTo investigate the clinical features, prevention and treatment of respiratory distress syndrome (RDS) in neonates of different gestational ages (GA) in the tertiary hospitals in Northwest China.Methods A total of 440 neonates diagnosed with RDS between January and December, 2011 in 12 tertiary hospitals in Northwest China were enrolled and classified into three groups: early preterm (GA<34 weeks;n=247), late preterm (GA 34-36+6 weeks;n=131) and full-term (GA≥37 weeks;n=62). The clinicaldata, including perinatal factors, prevention and treatment, complications and prognosis, were comparatively analyzed among the three groups.ResultsThe rate of multiple births in the early preterm group was higher than the other two

  16. Correlation between Industrial Carbon Emission and Its Affecting Factors——A Study Based on Empirical Analysis of Panel Data from the Five Provinces and Autonomous Regions in Northwest China%产业碳排放与影响因素的关联度——基于西北5省面板数据的实证分析

    Institute of Scientific and Technical Information of China (English)

    张艳芳; 栗新巧

    2014-01-01

    运用西北5省1999-2010年的面板数据,计算产业碳排放量,采用灰色关联度模型,分析影响因素与产业碳排放量之间的关联程度.结果显示:①从总量来看,1999-2010年西北5省产业碳排放量呈现波动增加的趋势,陕西、甘肃、青海、宁夏和新疆的碳排放量分别从1999年的3.22 ×107 t、3.05×107 t、7.80×106 t、1.12×107 t和3.02×107 t增加到2010年的1.24 ×108 t、6.86×107 t、2.15×107 t、5.76×107t和9.29×107 t,从2008年起,陕西省的碳排放量开始高于全国平均值.从人均碳排放量来看,也呈现出波动增加趋势,宁夏的人均碳排放量在不同年份均高于其他4省.②从空间来看,西北5省之间的产业碳排放量存在内部差异,其排序为:陕西>新疆>甘肃>宁夏>青海.③西北5省产业碳排放量与影响因素之间的关联度有某种相似之处,共同表现出:经济效应>人口效应>结构效应>技术效应.④不同影响因素对产业碳排放量的关联度存在省际之间的差异,人口效应表现为:宁夏>甘肃>新疆>青海>陕西,经济效应表现为:新疆>宁夏>青海>陕西>甘肃,结构效应表现为:甘肃>宁夏>青海>新疆>陕西,技术效应表现为:宁夏>青海>新疆>陕西>甘肃.%The global environment problems caused by carbon emission attract more and more attention all over the world,the study on regional industrial carbon emission can provide the theoretical basis to the countries for saving energy,reducing carbon emission and exploring low-carbon development path.In this paper,the relationships between the industrial carbon emission and its affecting factors were analyzed using the grey correlation model based on the panel data from the five provinces and autonomous regions in northwest China during the period of 1999-2010,which included the data of energy consumption,GDP,population,and calculated industrial carbon emission.The results are as follows

  17. Study on site selection of cold chain logistics in northwest territories

    Science.gov (United States)

    Liu, Yubin; Ren, Zongwei

    2017-08-01

    In this research, we mainly studied the Site selection problem of cold chain logistics in northwest of China. In the first place, we counted the demands of cold chain products in northwest territories, and then classified it into the Site selection problem in five provinces in northwest territories(Xinjiang, Qinghai, Gansu, Ningxia, Shanxi); Next, we used the Center of gravity Method to select initial location; Finally, we established the location of distribution by using Analytic Hierarchy Process (AHP)and fuzzy comprehensive evaluation method. Comparing with the traditional method, this method not only considered the cost of transportation and distance, but also deliberated the physical condition, social environment and economics condition which associated with Site selection problem.