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Effects of Health Education with Problem-Based Learning Approaches on the Knowledge, Attitude, Practice and Coping Skills of Women with High-Risk Pregnancies in Plateau Areas
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作者 Ying Wu Suolang Sezhen +5 位作者 Renqing Yuzhen Hong Wei Zhijuan Zhan Baima Hongying Yuhong Zhang Lihong Liu 《Open Journal of Nursing》 2024年第5期192-199,共8页
Objective: Given the unique cultural background, way of life, and physical environment of the Tibetan Plateau, this study aims to investigate the effects of health education using problem-based learning (PBL) approach... Objective: Given the unique cultural background, way of life, and physical environment of the Tibetan Plateau, this study aims to investigate the effects of health education using problem-based learning (PBL) approaches on the knowledge, attitude, practice, and coping skills of women with high-risk pregnancies in this region. Methods: 76 high-risk pregnancy cases were enrolled at Tibet’s Linzhi People’s Hospital between September 2023 and April 2024. 30 patients admitted between September 2023 and December 2023 were selected as the control group and were performed with regular patient education. 46 patients admitted between January 2024 and April 2024 were selected as the observation group and were performed regular patient education with problem-based learning approaches. Two groups’ performance on their health knowledge, attitude, practice and coping skills before and after interventions were evaluated, and patient satisfaction were measured at the end of the study. Results: There was no statistical significance (P P P Conclusions: Health education with problem-based learning approaches is worth promoting as it can help high-risk pregnant women in plateau areas develop better health knowledge, attitude and practice and healthier coping skills. Also, it can improve patient sanctification. 展开更多
关键词 plateau areas Patients with High-Risk Pregnancies Problem-Based Learning Health Education Health Knowledge Attitude and Practice Coping Skills
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A Multi-Center Randomized Controlled Study UsingΔP_(CO2)/Ca-v_(O2)as the Target to Guide Early Tissue Hypoperfusion in Sepsis in Plateau Areas
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作者 Lianyu Zhang Fabin Zhang +6 位作者 Huanying Bai Huibin Yun Zhao Zheng Shuncai Liu Shenghua A Zhongshan Shi Yuhai Hu 《Journal of Clinical and Nursing Research》 2024年第1期187-195,共9页
Objective:To explore the value of using the venous-arterial carbon dioxide partial pressure difference and the arterial-venous oxygen content difference ratio(ΔP_(CO2)/Ca-v_(O2))as targets to guide early tissue hypop... Objective:To explore the value of using the venous-arterial carbon dioxide partial pressure difference and the arterial-venous oxygen content difference ratio(ΔP_(CO2)/Ca-v_(O2))as targets to guide early tissue hypoperfusion in sepsis in plateau areas.Methods:90 sepsis patients admitted to the Third People’s Hospital of Xining and Golmud People’s Hospital from June 2017 to December 2022 were selected as the research subjects,and they were divided into the Scv_(O2)(central venous oxygen saturation)group and theΔP_(CO2)/Ca-v_(O2)group,with 45 cases in each group.The two groups were treated with early shock resuscitation according to different protocols.The hemodynamic characteristics of the two groups of patients before and after resuscitation were observed,and the volume responsiveness was evaluated.The ROC(receiver operating characteristic)curve was used to analyze the significance ofΔP_(CO2)/Ca-v_(O2),Scv_(O2),lactate,lactate clearance,and urine output in evaluating patient prognosis and the correlation betweenΔP_(CO2)/Ca-v_(O2)and the above indicators was explored.Results:Compared with before resuscitation,after fluid resuscitation,the heart rate(HR),mean arterial pressure(MAP),central venous pressure(CVP),cardiac index(CI),lactate,lactate clearance rate,and urine output of the two groups of patients were significantly improved(P<0.05);in terms of therapeutic effect,the 28-day mortality rate,6-hour fluid balance,and lactic acid clearance of theΔP_(CO2)/Ca-v_(O2)group were better than the Scv_(O2)group.The ROC characteristic curve showed that theΔP_(CO2)/Ca-v_(O2)value can effectively predict the prognosis of patients(AUC=0.907,sensitivity was 97%,specificity was 72.4%,and critical value was 1.84).ΔP_(CO2)/Ca-v_(O2)significantly correlated with Scv_(O2),lactic acid,and lactic acid clearance rate.Conclusion:TheΔP_(CO2)/Ca-v_(O2)value can be used to guide fluid resuscitation in early hypoperfusion in sepsis in plateau areas,improve patients’hemodynamics,reduce lactate indicators,and increase urine output.ΔP_(CO2)/Ca-v_(O2)level>1.84 can effectively improve patient prognosis. 展开更多
关键词 ΔP_(CO2)/Ca-v_(O2) Scv_(O2) SEPSIS plateau area Prognosis
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Relationship Between Agriculture and Ecological Deterioration,Restoration and Reconstruction in Loess Plateau Areas of Northwest China 被引量:2
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作者 CHENG Xu( China Agricultural University, Beijing 100094) 《Agricultural Sciences in China》 CAS CSCD 2002年第1期114-120,共7页
A comprehensive analysis was conducted on the current situation as well as historic succession processor agriculture and ecological conditions in Northwest China, in particular in the Loess Plateau, by means of a inte... A comprehensive analysis was conducted on the current situation as well as historic succession processor 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. 展开更多
关键词 Loess plateau Area of Northwest China Agricultural ecology
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Spatial pattern and mechanisms of farmland abandonment in Agricultural and Pastoral Areas of Qingzang Plateau 被引量:2
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作者 Yuling Li Tao Zhou +3 位作者 Guanghui Jiang Guangyong Li Dingyang Zhou Yu Luo 《Geography and Sustainability》 2021年第3期139-150,共12页
With the rapid development of social economy and urban−rural integration,the phenomenon of farmland aban-donment worldwide has proved to be one of the main trends of land use and land cover change(LUCC),and profoundly... With the rapid development of social economy and urban−rural integration,the phenomenon of farmland aban-donment worldwide has proved to be one of the main trends of land use and land cover change(LUCC),and profoundly affected the rural landscape and regional ecological environment.Restricted by the natural environ-ment,economic development and backward agricultural technology,the phenomenon of farmland abandonment is also common in the Qingzang Plateau(QP).Therefore,this paper adopted the spatial autocorrelation method to analyze the spatial pattern of abandonment in the agricultural and pastoral areas of the Qingzang Plateau(APA−QP)in 2017,and the geographically weighted regression(GWR)model to explore the effects of geograph-ical resources,socio-economic development and location conditions on farmland abandonment.This study found that:1)From 2015 to 2017,the abandoned farmland area in the APA−QP was approximately 18.23×10^(4)ha,with an overall abandonment rate of 15.18%.On the whole,it showed the distribution characteristics of“strong in the south and weak in the north,strong in the east and weak in the west”.2)There were positive spatial correlation between both abandoned area and abandonment rate in the APA−QP,showing“concave”and“convex”patterns,respectively,mainly concentrated in the Huang−shui Valley and the Southeast Tibet;while in the western and northern regions,the degree of abandonment was relatively low.3)Farmland abandonment in the APA−QP was mainly driven by the geographical environment changes and farmers’decision−making on farmland utilization.There was significant spatial heterogeneity on farmland abandonment associated with the impact of geographical resources,socio−economics and location conditions.The geographical resource factors had a positive impact on the abandonment,and were strongly constrained by natural geographic conditions such as altitude and slope.The farmland resources in the Qingzang Plateau are limited,but are of strategic significance for the sustainable development of agriculture in the whole Qingzang Plateau.In order to realize the rational distribution of agricul-ture and animal husbandry and the sustainable utilization of farmland resources in the plateau region,land use strategies should be implemented according to regional differences and regional advantages in order to ensure the ecological environment security of Qingzang Plateau. 展开更多
关键词 Farmland abandonment Spatial pattern Formation mechanism Geographically weighted regression Qingzang plateau Agricultural and pastoral areas
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Comparison of LR,5-CV SVM,GA SVM,and PSO SVM for landslide susceptibility assessment in Tibetan Plateau area,China 被引量:1
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作者 ZHANG Ying-bin XU Pei-yi +5 位作者 LIU Jing HE Jian-xian YANG Hao-tian ZENG Ying HE Yun-yong YANG Chang-feng 《Journal of Mountain Science》 SCIE CSCD 2023年第4期979-995,共17页
The applicability of statistics-based landslide susceptibility assessment methods is affected by the number of historical landslides.Previous studies have proposed support vector machine(SVM)as a small-sample learning... The applicability of statistics-based landslide susceptibility assessment methods is affected by the number of historical landslides.Previous studies have proposed support vector machine(SVM)as a small-sample learning method.However,those studies demonstrated that different parameters can affect model performance.We optimized the SVM and obtained models as 5-fold cross validation(5-CV)SVM,genetic algorithm(GA)SVM,and particle swarm optimization(PSO)SVM.This study compared the prediction performances of logistic regression(LR),5-CV SVM,GA SVM,and PSO SVM on landslide susceptibility mapping,to explore the spatial distribution of landslide susceptibility in the study area in Tibetan Plateau,China.A geospatial database was established based on 392 historical landslides and 392 non-landslides in the study area.We used 11 influencing factors of altitude,slope,aspect,curvature,lithology,normalized difference vegetation index(NDVI),distance to road,distance to river,distance to fault,peak ground acceleration(PGA),and rainfall to construct an influencing factor evaluation system.To evaluate the models,four susceptibility maps were compared via receiver operating characteristics(ROC)curve and the results showed that prediction rates for the models are 84%(LR),87%(5-CV SVM),85%(GA SVM),and 90%(PSO SVM).We also used precision,recall,F1-score and accuracy to assess the quality performance of these models.The results showed that the PSO SVM had greater potential for future implementation in the Tibetan Plateau area because of its superior performance in the landslide susceptibility assessment. 展开更多
关键词 Tibetan plateau area Logistic regression Support vector machine Landslide susceptibility assessment
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Method for Evaluating the Reliability of Compressor Impeller of Turbocharger for Vehicle Application in Plateau Area 被引量:2
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作者 WANG Zheng WANG Zengquan +2 位作者 WANG A-na ZHUANG Li WANG Jinwei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第6期1218-1225,共8页
As turbocharging diesel engines for vehicle application are applied in plateau area, the environmental adaptability of engines has drawn more attention. For the environmental adaptability problem of turbocharging dies... As turbocharging diesel engines for vehicle application are applied in plateau area, the environmental adaptability of engines has drawn more attention. For the environmental adaptability problem of turbocharging diesel engines for vehicle application, the present studies almost focus on the optimization of performance match between turbocharger and engine, and the reliability problem of turbocharger is almost ignored. The reliability problem of compressor impeller of turhocharger for vehicle application when diesel engines operate in plateau area is studied. Firstly, the rule that the rotational speed of turbocharger changes with the altitude height is presented, and the potential failure modes of compressor impeller are analyzed. Then, the failure behavior models of compressor impeller are built, and the reliability models of compressor impeller operating in plateau area are developed. Finally, the rule that the reliability of compressor impeller changes with the altitude height is studied, the measurements for improving the reliability of the compressor impellers of turbocharger operating in plateau area are given. The results indicate that when the operating speed of diesel engine is certain, the rotational speed of turbocharger increases with the increase of altitude height, and the failure risk of compressor impeller with the failure modes of hub fatigue and blade resonance increases. The reliability of compressor impeller decreases with the increase of altitude height, and it also decreases as the increase of number of the mission profile cycle of engine. The method proposed can not only be used to evaluating the reliability of compressor impeller when diesel engines operate in plateau area but also be applied to direct the structural optimization of compressor impeller. 展开更多
关键词 TURBOCHARGER plateau area compressor impeller failure behavior RELIABILITY
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The effects of land use and its patterns on soil properties in a small catchment of the Loess Plateau 被引量:6
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作者 WANGJun FUBo-jie 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第2期263-266,共4页
Due to relatively strong human activities in the hilly area of Loess Plateau, the natural vegetation has been destroyed, and landscape pattern based on agricultural land matrix was land use mosaic composing of shrub l... Due to relatively strong human activities in the hilly area of Loess Plateau, the natural vegetation has been destroyed, and landscape pattern based on agricultural land matrix was land use mosaic composing of shrub land, grassland, woodland and orchard. This pattern has an important effect on soil moisture and soil nutrients. The Danangou catchment, a typical small catchment, was selected to study the effects of land use and its patterns on soil moisture and nutrients in this paper. The results are as follows: The comparisons of soil moisture among seven land uses for wet year and dry year were performed: (1) the average of soil moisture content for whole catchment was 12.11% in wet year, while it was 9.37% in dry year; (2) soil moisture among seven land uses was significantly different in dry year, but not in wet year; (3) from wet year to dry year, the profile type of soil moisture changed from decreasing type to fluctuation-type and from fluctuant type to increasing type; (4) the increasing trend in soil moisture from the top to foot of hillslope occurred in simple land use along slope, while complicated distribution of soil moisture was observed in multiple land uses along slope. The relationships between soil nutrients and land uses and landscape positions were analysed: (1) five nutrient contents of soil organic matter (SOM), total N (TN), available N (AN), total P (TP) and available P (AP) in hilly area were lower than that in other areas. SOM content was less than 1%, TN content less than 0.07%, and TP content between 0.05% and 0.06%; (2) SOM and TN contents in woodland, shrub land and grassland were significantly higher than that in fallow land and cropland, and higher level in soil fertility was found in crop-fruit intercropping land among croplands; (3) soil nutrient distribution and responses to landscape positions were variable depending on slope and the location of land use types. 展开更多
关键词 hilly area of Loess plateau land use pattern soil moisture soil nutrient
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Genesis of the Cenozoic Sodic Alkaline Basalt in the Xiahe–Tongren Area of the Northeastern Tibetan Plateau and its Continental Dynamic Implications 被引量:1
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作者 LAI Shaocong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第3期1047-1048,共2页
Objective The Cenozoic Indo-Asian collision caused significant crustal shortening and plateau uplift in the central Tibet. The extrusion tectonic model has been widely accepted to explain the strike-slip faults around... Objective The Cenozoic Indo-Asian collision caused significant crustal shortening and plateau uplift in the central Tibet. The extrusion tectonic model has been widely accepted to explain the strike-slip faults around the Tibetan Plateau. Previous studies indicate that the lower crust flow is the main drive force of the extrusion tectonics. Whether mantle extrusion process occurred during the Cenozoic uplift is a major problem to be addressed, which is significant for understanding the uplift mechanism and tectonic evolution of the Tibetan Plateau. 展开更多
关键词 Tongren Area of the Northeastern Tibetan plateau and its Continental Dynamic Implications Genesis of the Cenozoic Sodic Alkaline Basalt in the Xiahe
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A Study on Forest Species Diversity and Its Ecological Service Function in the Plateau Area of Western Sichuan
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作者 Deng Yu-lin, Wang Yu-kuan, Peng Pei-haoInstitute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03B期975-980,共6页
This paper presents a study on species diversity and its ecological service function in the plateau area in western Sichuan. The results show that species diversity in the plantations on the cutover land has a tendenc... This paper presents a study on species diversity and its ecological service function in the plateau area in western Sichuan. The results show that species diversity in the plantations on the cutover land has a tendency to increase and that its ecological service function is to be improved with stand age growing. The species diversity in forest communities is also gradually increased on different succession stage till reaching a climax level. But the species diversity in the climax community is slightly decreased before it reaches a relatively constant status. Ecological service function of diversity is gradually strengthened with the progress of succession. In addition, species diversity in a stand in a similar site and at a same age differs among forest types. Species diversity index within a coniferous and broad-leaved mixed forest is larger than that within a coniferous forest. Meanwhile, species diversity enriches as the tree density increases. 展开更多
关键词 bio-diversity ecological service function plateau area western Sichuan
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Path of Social Construction in Northwest Sichuan Plateau Pastoral Area
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作者 XU Ying-ming 《Asian Agricultural Research》 2012年第4期20-24,共5页
On the basis of main contents of social construction and key points of construction,this paper analyzes features of conditions of northwest Sichuan plateau pastoral area.The social construction at current stage mainly... On the basis of main contents of social construction and key points of construction,this paper analyzes features of conditions of northwest Sichuan plateau pastoral area.The social construction at current stage mainly includes social cause in narrow sense,and social management at meso-level.The northwest Sichuan plateau pastoral area is faced with the best policy and development opportunity.However,there are still many weak aspects.Firstly,social structure is not coordinated with economic structure.Secondly,social construction ability of grass-roots government is weak.Thirdly,the ability to respond to public demands is low.Fourthly,there is a big gap in availability of basic public service.Finally,it presents path selection for social construction of northwest Sichuan plateau pastoral area:strengthen social construction ability of grass-roots government;promote social construction with livelihood projects as key projects;boost social construction taking advantage of ecological construction;develop basic public service with the aid of external forces;intensify evaluation system for supervision of social construction works. 展开更多
关键词 Social construction Policy opportunity Weak parts Path selection Northwest Sichuan plateau pastoral area
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Combining gradual and abrupt analysis to detect variation of vegetation greenness on the loess areas of China
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作者 Panxing HE Zongjiu SUN +3 位作者 Dongxiang XU Huixia LIU Rui YAO Jun MA 《Frontiers of Earth Science》 SCIE CSCD 2022年第2期368-380,共13页
The annual peak growth and trend shift of vegetation are critical in characterizing the carbon sequestration capacity of ecosystems.As the well-known area with the fastest vegetation growth in the world,the Loess Plat... The annual peak growth and trend shift of vegetation are critical in characterizing the carbon sequestration capacity of ecosystems.As the well-known area with the fastest vegetation growth in the world,the Loess Plateau(LP)lands find an enhanced greening trend in the annual and growing-season.However,the spatiotemporal dynamics of vegetation peak growth and breakpoints characteristics on time series still needs to be explored.Here,we performed tendency analysis to characterize recent variations in annual peak vegetation growth through a satellite-derived vegetation index(NDVI_(max),Maximum Normalized Difference Vegetation Index)and then applied breakpoint analysis to capture abrupt points on the time series.The results demonstrated that the vegetation peak trend had been significantly increasing,with a growth rate at 0.68×10^(-2)·a^(-1) during 2001-2018,and most pixels(70.81%)have a positive linear greening trend over the entire LP.In addition,about 83%of the breakpoint type on the monthly NDVI time series is a monotonic increase at the pixel level,and most pixels(57%)have detected breakpoints after 2010.Our results also showed that the growth rate accelerates in the northwest and decelerates in the southeast after the breakpoint.This study indicates that combining abrupt analysis with gradual analysis can describe vegetation dynamics more effectively and comprehensively.The findings highlighted the importance of breakpoint analysis for monitor timing and shift using time series satellite data at a regional scale,which may help stakeholders to make reasonable and effective ecosystem management policies. 展开更多
关键词 vegetation greenness gradual trend BREAKPOINT BFAST algorithm the Loess plateau area
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青藏高原边缘区地震灾后的经济韧性及恢复效率——以汶川Ms 8.0地震极重灾区为例 被引量:7
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作者 周侃 刘宝印 樊杰 《Journal of Geographical Sciences》 SCIE CSCD 2020年第8期1363-1381,共19页
The border areas of the Tibetan Plateau and the neighboring mountainous areashave a high incidence of earthquakes with a magnitude greater than Ms 5.0, as well as havinga dense distribution of geological disasters suc... The border areas of the Tibetan Plateau and the neighboring mountainous areashave a high incidence of earthquakes with a magnitude greater than Ms 5.0, as well as havinga dense distribution of geological disasters such as collapses, landslides, and debris flows.Revealing the post-disaster economic development and recovery process is very importantfor enhancing disaster prevention and response capacity in order to formulate control policiesand recovery methods for post-disaster economic reconstruction based on economic resilience.Using long-term socioeconomic data and the autoregressive integrated moving average(ARIMA) model, this paper calculated the economic resilience index of the areas mostseverely affected by the Wenchuan Earthquake of 2008 and adopted the improved variablereturns to scale (VRS) date envelopment analysis (DEA) model and the Malmquist productivityindex to analyze the efficiency and effect of annual post-disaster recovery. The resultsshow that: (1) the economic resilience index of the areas most severely affected by theWenchuan Earthquake was 0.877. The earthquake resulted in a short-term economic recessionin the affected areas, but the economy returned to pre-quake levels within two years. Inaddition, the industrial economy was less resilient than agriculture and the service industry. (2)The comprehensive economic recovery efficiency of the disaster-stricken area in the yearfollowing the disaster was 0.603. The comprehensive efficiency, the pure technical efficiency,and the scale efficiency of the plain and hilly areas were significantly greater than those of theplateau and mountain areas. (3) The annual fluctuation in total factor productivity (TFP) followingthe disaster was considerable, and the economic recovery efficiency decreased significantly,resulting in a short-term economic recession. The TFP index returned to steadystate following decreases of 33.7% and 15.2%, respectively, in the two years following thedisaster. (4) The significant decrease in the post-disaster recovery efficiency was causedmainly by technological changes, and the renewal of the production system was the leading factor in determining the economic resilience following the disaster. With the decline in thescale of economic recovery following the earthquake, long-term economic recovery in thedisaster-stricken areas depended mainly on pure technical efficiency, and the improvement inthe latter was the driving force for maintaining the long-term growth of the post-disastereconomy. Therefore, according to the local characteristics of natural environment and economicsystem, the disaster-stricken areas need to actively change and readjust their economicstructures. At the same time, attention should be paid to updating the production systemto enhance the level of technological progress and give full play to the scale effects oflarge-scale capital, new facilities, human resources, and other investment factors followingthe disaster so as to enhance the impact of economic resilience and recovery efficiency inresponse to the disaster. 展开更多
关键词 economic resilience recovery efficiency Malmquist productivity index post-disaster reconstruction area Wenchuan Earthquake border areas of the Tibetan plateau
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Sr-Nd-Pb Isotopic Compositions of the Neogene Eolian Deposits in the Xining Basin and Implications for Their Dust Sources 被引量:4
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作者 Fangming Zeng Meiyan Liang +2 位作者 Shuzhen Peng Dongmei Yu Shuyuan Xiang 《Journal of Earth Science》 SCIE CAS CSCD 2015年第5期669-676,共8页
The Neogene eolian deposits in the Xining Basin are valuable archive for studying the evolution of the Asian monsoon system and geomorphic processes of Northwest China. The Neogene eolian deposits that paleomagnetical... The Neogene eolian deposits in the Xining Basin are valuable archive for studying the evolution of the Asian monsoon system and geomorphic processes of Northwest China. The Neogene eolian deposits that paleomagnetically dated at about 14 Ma probably were sourced from the middle and west Qinghai-Tibetan Plateau(QTP) as indicated by elemental compositions and magnetic properties. This study provides the Sr-Nd-Pb isotopic ratios of different sediments(gravels from the river terraces, Neogene eolian deposits and Quaternary loess) in the Xining Basin. The results show that:(1) Sr-Nd isotopic compositions of terrace gravels are different from those of the Neogene and Quaternary eolian deposits, although the Nd isotope ratios of gravel on the 10 th terrace(T10) and eolian deposits are similar.(2) Pb isotopic compositions of river gravels are obviously different from the eolian deposits in the Xining Basin. However, Pb isotopic compositions of eolian deposits in the basin are similar to those of eolian deposits in the central Chinese Loess Plateau.(3) Sr-Nd-Pb isotope results indicate that the Neogene eolian deposits in the Xining Basin were probably sourced from remote areas outside of the basin by long-distance transportation. The Qaidam Basin is probably an important source area for the eolian deposits in the Xining Basin. 展开更多
关键词 eolian deposits Qinghai-Tibetan plateau Sr-Nd-Pb isotope source area
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Hydrological cycle research by D&^(18)O tracing in small watershed in the loess hilly region
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作者 Xu Xuexuan Zhao Jiaona Zhang Xiaoni 《International Soil and Water Conservation Research》 SCIE 2013年第3期75-82,共8页
The objective of this study was to determine the mechanisms of the hydrologic cycle in the loess area in China.Sixty eight water samples from precipitation,soil water of the 0-4 m layer,surface water in the valley,gro... The objective of this study was to determine the mechanisms of the hydrologic cycle in the loess area in China.Sixty eight water samples from precipitation,soil water of the 0-4 m layer,surface water in the valley,ground water(spring and well)were collected and the Deuterium(D)and Oxygen-18(^(18)O)of these water samples were analyzed to interpret the relationship among those waters in the watershed in the loess hilly region during 2005-2009.The results show that:the D&^(18)O of precipitation in Yangou was consistent with that of Xi,an,apparently the north migration of water vapor in Xi^an;according to the correlations among the differential waters in D&^(18)O,confirmed that precipitation recharge could account for most of the sources of valley flow,with part of the recharge water going to soil water recharge.The D&^(18)O of groundwater were very close to that of precipitation,likely the soil preferential flow was dominant in groundwater recharge although the infiltration had a certain lag.Under the influence of rainfall and evaporation,the response of the soil moisture profile,and its D&^(18)O profile were different.The soil moisture had the strong influenced layer in the 60-160 cm range,a weak impacted layer in 60 l60 cm,and a stable layer below l60 cm.It was shown that the soil evaporation depth could be up to l60 cm because the D&^(18)O changed in that depth.The study could increase our understanding of the magnitude and pattern of the hydrologic cycle,which should improve water resources management in the watershed scale. 展开更多
关键词 Hilly area in the Loess plateau PRECIPITATION GROUNDWATER Soil water D&^(18)O
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