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“异”时空里的国家认同——以傅查新昌《秦尼巴克》为分析文本
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作者 兑文强 《广西师范学院学报(哲学社会科学版)》 2015年第5期60-65,共6页
近代以来,由于清政府腐败黑暗的统治,锡伯族戍边移民的国家认同意识一度相当薄弱。新中国建国以后,随着新疆各项社会改革的完成,以锡伯族为代表的少数民族的国家认同意识完成了新的转变和确立。《秦尼巴克》提供了一个认识和考察近代以... 近代以来,由于清政府腐败黑暗的统治,锡伯族戍边移民的国家认同意识一度相当薄弱。新中国建国以后,随着新疆各项社会改革的完成,以锡伯族为代表的少数民族的国家认同意识完成了新的转变和确立。《秦尼巴克》提供了一个认识和考察近代以来边疆少数民族国家认同意识发展变化的经典文本。通过对这部小说的分析讨论,不难得出结论,国家认同的重要前提就是政治的稳定和经济的发展。 展开更多
关键词 锡伯族 “异”时空 国家认同
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Study on the Relationship among Forest Fire,Temperature and Precipitation and Its Spatial-temporal Variability in China 被引量:9
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作者 吕爱锋 《Agricultural Science & Technology》 CAS 2011年第9期1396-1400,共5页
[Objective] The aim was to discuss the relationship between forest fire and meterological elements (precipitation and temprature) in each region of China.[Method] Firstly,the average precipitation and temperature in... [Objective] The aim was to discuss the relationship between forest fire and meterological elements (precipitation and temprature) in each region of China.[Method] Firstly,the average precipitation and temperature in forest area of each province in fire season were obtained based on meterological data,forest distribution data,seasonal and monthly data of forest fire in China.Secondly,the relationship among forest fire area,precipitation and temperature was discussed through temporal and correlation analysis.[Result] The changes of precipitation and temperature with time could reflect the annual variation of fire area well.Forest fire area went up with the decrease of precipitation and increase of temprature,and visa versa.Meanwhile,there existed diffirences in the relationship in various regions over time.Correlation analyses revealed that there was positive correlation between forest fire area and temperature,especailly Northwest China (R=0.367,P〈0.01),Southwest China (R=0.327,P〈0.05),South China (R=0.33,P〈0.05),East China (R=0.516,P〈0.01) and Xinjiang (R=0.447,P〈0.05) with obviously positive correlation.At the same time,the correlation between forest fire area and precipitation was significantly positive in Northwest China (R=0.482,P〈0.01),while it was significantly negaive in South China (R=-0.323,P=0.03),but there was no significant correlation in other regions.[Conclusion] Relationships between forest fire and meteorological elements (precipitation and temprature) revealed in the study would be useful for fire provention and early warning in China. 展开更多
关键词 Forest fire PRECIPITATION TEMPERATURE Spatial-temporal variability
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Temporal-Spatial Variances of Holocene Precipitation at the Marginal Area of the East Asian Monsoon Influences from Pollen Evidence 被引量:6
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作者 刘鸿雁 崔海亭 +1 位作者 田育红 徐丽宏 《Acta Botanica Sinica》 CSCD 2002年第7期864-871,共8页
The woodland-steppe ecotone in the. southern Nei Mongol Plateau is located at the northern edge of the east Asian monsoon influences. A marked southeastern - northwestern (SE - NW) precipitation gradient exists in thi... The woodland-steppe ecotone in the. southern Nei Mongol Plateau is located at the northern edge of the east Asian monsoon influences. A marked southeastern - northwestern (SE - NW) precipitation gradient exists in this region. Quantitative reconstruction of palaeo-precipitation of this region is helpful to reveal the development of monsoon climate and to predict die future desertification. Based on modern vegetation and surface pollen studies, a pollen-precipitation transfer function in the study region was established. Pollen data from three sediment sequences within the ecotone were used to reconstruct palaeo-precipitation during the Holocene. The processes of precipitation changes in the three sequences were quite different. There was a tendency of precipitation declined from the onset of the Holocene to 1 100 a BP in Haoluku. But, in Liuzhouwan and Xiaoniuchang, both located south of Haoluku, the annual precipitation reached highest values during 7 800 - 6 200 a BP and 7 200 - 5 000 a BP, respectively. The influences of southwestern (SW) monsoon and the variances of topographical conditions have possibly caused these temporal-spatial variances. 展开更多
关键词 marginal area of the monsoon climate WOODLAND steppe ecotone Nei Mongol Plateau pollen-climate transfer function
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Spatial and Temporal Differences of Urban Land Comprehensive Carrying Capacity in Guangxi
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作者 杨如军 邢玉玲 詹长根 《Agricultural Science & Technology》 CAS 2017年第6期1126-1132,共7页
The comprehensive carrying capacity of urban land can reflect the re- source level, economic scale, social development and environmental pressure of ur- ban land carrying. The assessment indicator system of urban land... The comprehensive carrying capacity of urban land can reflect the re- source level, economic scale, social development and environmental pressure of ur- ban land carrying. The assessment indicator system of urban land comprehensive carrying capacity was constructed from the 4 aspects of resource, economy, society, environment, and principal component analysis and cluster analysis were used to evaluate the urban land comprehensive carrying capacity of Guangxi and the 14 cities in 2005-2014, and analyzed its spatial and temporal characteristics as well as the driving forces, with the aim to provide references for improving the urban land comprehensive carrying capacity. The results showed that, the overall urban land comprehensive carrying capacity in Guangxi increased in 2005-2014, and there were significant differences in the land comprehensive carrying capacities among the cities in Guangxi in 2005-2014, in which Liuzhou, Guilin, Nanning belonged to the regions with the highest carrying capacity, while Beihai, Yulin, Wutong belonged to the regions with high carrying capacity, and the carrying capacities of the other cities changed with the changes of time. The economic development degree was an important factor influencing urban land comprehensive carrying capacity, but could not directly represent the urban land comprehensive carrying capacity level. 展开更多
关键词 Urban land comprehensive carrying capacity GUANGXI Principal compo- nent analysis Temporal and spatial difference Assessment indicator system Influ- encing factors
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SPATIAL-TEMPORAL CHANGES AND TRENDS OF AGEING IN CHINA 被引量:1
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作者 WANG Wu-yi ZHANG Li +3 位作者 LI Hai-rong LI Ri-bang YANG Lin-sheng LIAO Yong-feng 《Chinese Geographical Science》 SCIE CSCD 2005年第3期200-205,共6页
This study focuses on the development stages of ageing and its regional differences in China based on examination of official statistics and documents. The development of ageing in China has experienced three major st... This study focuses on the development stages of ageing and its regional differences in China based on examination of official statistics and documents. The development of ageing in China has experienced three major stages. Firstly, in the 1950s, low coefficient of elderly population (over 65 years) paced up to primary adult type. Secondly, there was a deeply drop of the elderly population because of natural disaster and political factors in the 1960s. Thirdly, from the 1970s to the end of 20th century, the constant increasing of elderly coefficient made China close to elderly society. With statistic data of population, Logistic model is used to simulate the future development of ageing, and two characteristics of development of ageing are presented. Firstly, as for ageing from 2005 to 2050, the elderly coefficient will grow up significantly from 8.48% to 16.30%. Secondly, after 2025, the increasing rate of elderly coefficient will slow down gradually. The regional differences of elderly population in China can be summarized as follows: 1) the eastern China possesses higher elderly coefficient and huger elder population than the western China; 2) about 47.4% of municipalities and provinces in the eastern China become elderly especially Shanghai, Zhejiang Province, Jiangsu Province, Beijing, Tianjin and Shandong Province; 3) ageing intensity is higher in rural area than urban area but getting close each other, and there are more elderly people in rural area than in urban area. Therefore, these will arose aged care problems, and it becomes important issue to establish the social security system in rural areas as soon as possible for elderly people. 展开更多
关键词 ageing ageing in rural area China
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Characteristics of Spatial and Temporal Variations of Monthly Mean Surface Air Temperature over Qinghai-Tibet Plateau 被引量:7
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作者 ZHANG Qianggong KANG Shichang YAN Yuping 《Chinese Geographical Science》 SCIE CSCD 2006年第4期351-358,共8页
The recorded meteorological data of monthly mean surface air temperature from 72 meteorological stations over the Qinghal-Tibet Plateau in the period of 1960-2003 have been analyzed by using Empirical Orthogonal Funct... The recorded meteorological data of monthly mean surface air temperature from 72 meteorological stations over the Qinghal-Tibet Plateau in the period of 1960-2003 have been analyzed by using Empirical Orthogonal Function (EOF) method, to understand the detailed features of its temporal and spatial variations. The results show that there was a high consistency of the monthly mean surface air temperature, with a secondarily different variation between the north and the south of the plateau. Warming trend has existed at all stations since the 1960s, while the warming rates were different in various zones. The source regions of big rivers had intense warming tendency. June, November and December were the top three fast-warming months since the 1960s; while April, July and September presented dramatic warming tendency during the last decade. 展开更多
关键词 monthly mean surface air temperature climatic variation EOF analysis Qinghai-Tibet Plateau
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Spatial and Temporal Variability of Thermal Stress to China's Coral Reefs in South China Sea 被引量:7
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作者 ZUO Xiuling SU Fenzhen +2 位作者 WU Wenzhou CHEN Zhike SHI Wei 《Chinese Geographical Science》 SCIE CSCD 2015年第2期159-173,共15页
Coral bleaching, caused by elevated sea surface temperature(SST), is occurring more frequently and seriously worldwide. Due to the lack of field observations, we understand little about the large-scale variability of ... Coral bleaching, caused by elevated sea surface temperature(SST), is occurring more frequently and seriously worldwide. Due to the lack of field observations, we understand little about the large-scale variability of thermal stress in the South China Sea(SCS) and its effect on China's coral reefs. This paper used 4-km high resolution gap-filled SST(Filled SST) data and thermal stress data related to coral bleaching derived from Coral Reef Temperature Anomaly Database(Co RTAD) to quantify the spatial and temporal characteristics of chronic thermal stress and acute thermal stress to China's coral reefs in SCS from 1982 to 2009. We analyzed the trend of SST in summer and the thermal stress frequency, intensity and duration during this period. The results indicate that, as a chronic thermal stress, summer mean SST in SCS shows an average upward trend of 0.2℃/decade and the spatial pattern is heterogeneous. Waters of Xisha Islands and Dongsha Islands of the northern SCS are warming faster through time compared to Zhongsha Islands and Nansha Islands sea areas of the southern SCS. High frequency bleaching related thermal stress events for these reefs are seen in the area to the northwest of Luzon Island. Severe anomaly thermal stress events are more likely to occur during the subsequent year of the El Nino year for these coral reefs. Besides, the duration of thermal stress varies considerably by anomaly year and by region. 展开更多
关键词 coral reef sea surface temperature(SST) thermal stress El Nino-Southern Oscillation(ENSO) South China Sea(SCS)
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Spatio-temporal Variation of Landscape Heterogeneity under Influence of Human Activities in Xiamen City of China in Recent Decade 被引量:3
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作者 HUANG Yixiong YIN Xiuqin +5 位作者 YE Gongfu LIN Jiemin HUANG Ru WANG Na WANG Liang SUN Yue 《Chinese Geographical Science》 SCIE CSCD 2013年第2期227-236,共10页
Xiamen is an economically competitive and highly urbanized city along the coastal area of Fujian Province, China. The research on spatio-temporal variation of landscape heterogeneity under the influence of human activ... Xiamen is an economically competitive and highly urbanized city along the coastal area of Fujian Province, China. The research on spatio-temporal variation of landscape heterogeneity under the influence of human activities is of great importance to the further study on the relationship of landscape pattern and ecological process. It is also crucial to the discovery of spatial variation and intensity distribution of human activities. The research analyzed the intensity of human impacts and the spatial variation features and dynamics of landscape patterns by introducing statistical theories and approaches. We analyzed spatio-temporal variation of landscape heterogeneity using the geostatistical techniques, such as semivariogram and Kriging interpolation.Results show that there is a higher correlation between landscape heterogeneity indexes and human impact index. Both the indexes show a moderate spatial autocorrelation as well as an obvious characteristic of anisotropy. From 1998 to 2008, the spatial differentiation of the changes in the intensity of human activities and the changes in landscape heterogeneity shows that the landscape patterns in Xiamen are closely related with the urban land utilization methods, the condition of traffic and geographical location and the physical geographical condition such as the terrain and the ecological environment. The process of urbanization has a significant impact on the urban landscape pattern. 展开更多
关键词 landscape heterogeneity human impact index human activities Xiamen City
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Temporal and Spatial Variability of Dissolved Organic Carbon Concentration in the Xijiang River, South China 被引量:4
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作者 TAO Zhen GAO Quanzhou +5 位作者 GUO Wenping WANG Zhengang ZHANG Yongling XIE Chenji HUANG Xiakun ZHONG Hongwei 《Journal of Mountain Science》 SCIE CSCD 2011年第5期694-703,共10页
A whole year analysis of riverine dissolved organic carbon (DOC) concentrations in the Xijiang River (XJR), South China, showed that the mean riverine DOC concentration (1.24 mg L-1) in the XJR was notably lower than ... A whole year analysis of riverine dissolved organic carbon (DOC) concentrations in the Xijiang River (XJR), South China, showed that the mean riverine DOC concentration (1.24 mg L-1) in the XJR was notably lower than the averaged value (5.75 mg L-1) of the global riverine DOC concentration in several major rivers. There is an inconspicuous monthly fluctuation of the DOC signal in the XJR, but on a semi-yearly time scale, however, the riverine DOC concentration had significant difference between hydrological seasons. The DOC level during the flood season (1.18 mg L-1) was less than that during the non-flood season (1.40 mg L-1). Owing to the concomitance of the flushing and dilution effects of the runoff during the high-water period, the variation of riverine DOC concentration with discharge in the XJR differed from that reported in many other major rivers. The DOC export flux above the city of Wuzhou was about 0.62× 106 g C km-2 yr-1. The DOC transported during the "056" Massive Flood period comprised 30.35% of the annual total, while the discharge accounted for 36.32% of the total annual flow. The characteristics in riverine DOC concentration in the XJR were attributed to the combined effect of the geomorphologic, monsoon climatic and hydrological processes as well as land-use within the drainage basin. 展开更多
关键词 Export flux Hydrological processes Massive flood Riverine dissolved organic carbon The Xijiang River
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Temporal and spatial differences and imbalance of China's urbanization development during 1950-2006 被引量:7
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作者 方创琳 刘晓丽 《Journal of Geographical Sciences》 SCIE CSCD 2009年第6期719-732,共14页
A better understanding of the regional disparity and imbalance characteristics of China's urbanization development is the important premise for constituting correct policy and strategy and promoting the healthy an... A better understanding of the regional disparity and imbalance characteristics of China's urbanization development is the important premise for constituting correct policy and strategy and promoting the healthy and sustainable development of urbanization in the 21st century. The regional differences of China's urbanization level have close relations with natural conditions of landform and climate etc.,the urbanization level reduces with the eleva-tion of topography and decrease of precipitation. According to the statistical data set of ur-banization in 1950-2006,the temporal change course of inter-provincial disparity of Chinese urbanization level since the founding of New China in 1949 was studied,and then the inter-regional and intra-regional disparities of urbanization development were analyzed by the Theil index and its nested decomposition method,to grasp the dynamic change of spatial disparities of China's urbanization level on the whole. Using the imbalance index model,the imbalance status of urban population distribution relative to total population,grain output,total agricultural output value,gross output value of industry,tertiary industrial output value as well as gross regional product was discussed,to hold the balance characteristics of urbanization development relative to the regional development conditions from the macroscopic scales. 展开更多
关键词 URBANIZATION DIFFERENCE imbalance index China
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Spatio-temporal Differentiation of Residential Land for Coastal Town: A Case Study of Dalian Jinshitan 被引量:3
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作者 YANG Jun SUN Jing +2 位作者 ZHAO Hongdan XI Jianchao LI Xueming 《Chinese Geographical Science》 SCIE CSCD 2016年第4期566-576,共11页
Based on SPOT5 satellite remote sensing images and land use data in five time phases covering the period 1988–2012, the distribution characteristics, spatial differentiation processes, and driving mechanisms affectin... Based on SPOT5 satellite remote sensing images and land use data in five time phases covering the period 1988–2012, the distribution characteristics, spatial differentiation processes, and driving mechanisms affecting the residential land of the Jinshitan Tourist Resort were studied. The work included a combination of GIS technology, adoption of the differentiation index D, and the multi-group differentiation-measure model D(m). The results provided a basis for the following conclusions: 1) From 1988 to 2012, the degree of differentiation of the rural residential land first decreased, and then increased. The general residential, commercial residential and garden-house land-types all showed declining trends, of which the garden-house type presented the most intense volatility. 2) The overall background of the traditional residential land type was gradually replaced by a new residential land type, and the total area of residential land increased year by year, significantly improving the overall residential conditions. The areas of the new residential land type showed growth, and were increasingly widely distributed in the coastal tourist resorts, transportation corridors, and scenic areas. 3) Government policy, social differentiation, market mechanisms, and individual choices(along with other factors) were mutually promoted, although still restrained. However, all of these factors interacted to constrain the developmental direction and the processes affecting tourism real estate in the Dalian Jinshitan Tourist Resort. 展开更多
关键词 residential space differentiation differentiation degree residential conditions driving mechanism Dalian Jinshitan
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Spatial-temporal Heterogeneity of Industrial Structure Transformation and Carbon Emission Effects in Xuzhou Metropolitan Area 被引量:2
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作者 QIU Fangdao YUAN He +1 位作者 BAI Liangyu LI Fei 《Chinese Geographical Science》 SCIE CSCD 2017年第6期904-917,共14页
Employing decoupling index and industrial structure characteristic bias index methods, this study analyzed the spatial-temporal characteristics of industrial structure transformations and their resulting carbon emissi... Employing decoupling index and industrial structure characteristic bias index methods, this study analyzed the spatial-temporal characteristics of industrial structure transformations and their resulting carbon emissions in the Xuzhou Metropolitan Area from 2000 to 2014, with a focus on their relationships and driving factors. Our research indicates that carbon emission intensity from industrial structures in the Xuzhou Metropolitan Area at first showed an increasing trend, which then decreased. Furthermore, the relationship between emissions and industrial economic growth has been trending toward absolute decoupling. From the perspective of the center-periphery, the Xuzhou Metropolitan Area formed a concentric pattern, where both progress towards low emissions and the level of technological advancement gradually diminished from the center to the periphery. In terms of variation across provinces, the ISCB index in the eastern Henan has decreased the slowest, followed by the southern Shandong and the northern Anhui, with the northern Jiangsu ranking last. During this period, resource-and labor-intensive industries were the primary growth industries in the northern Anhui and the eastern Henan, while labor-intensive industries dominated the southern Shandong and capital-intensive industries dominated the northern Jiangsu. In terms of city types, the spatial pattern for industrial structure indicates that recession resource-based cities had higher carbon emission intensities than mature resource-based cities, followed by non-resource-based cities and regenerative resource-based cities. Generally, the industrial structure in the Xuzhou Metropolitan Area has transformed from being resource-intensive to capital-intensive, and has been trending toward technology-intensive as resource availability has been exploited to exhaustion and then been regenerated. Industrial structure has been the leading factor causing heterogeneity of carbon emission intensities between metropolitan cities. Therefore, the key to optimizing the industrial structure and layout of metropolitan areas is to promote industrial structure transformation and improve the system controlling collaborative industrial development between cities. 展开更多
关键词 industrial structure transformation industrial structure characteristic bias carbon emission effect spatial-temporal pattern Xuzhou Metropolitan Area
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Gas monitoring data anomaly identification based on spatio-temporal correlativity analysis 被引量:3
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作者 Shi-song ZHU Yun-jia WANG Lian-jiang WEI 《Journal of Coal Science & Engineering(China)》 2013年第1期8-13,共6页
Based on spatio-temporal correlativity analysis method, the automatic identification techniques for data anomaly monitoring of coal mining working face gas are presented. The asynchronous correlative characteristics o... Based on spatio-temporal correlativity analysis method, the automatic identification techniques for data anomaly monitoring of coal mining working face gas are presented. The asynchronous correlative characteristics of gas migration in working face airflow direction are qualitatively analyzed. The calculation method of asynchronous correlation delay step and the prediction and inversion formulas of gas concentration changing with time and space after gas emission in the air return roadway are provided. By calculating one hundred and fifty groups of gas sensors data series from a coal mine which have the theoretical correlativity, the correlative coefficient values range of eight kinds of data anomaly is obtained. Then the gas moni- toring data anomaly identification algorithm based on spatio-temporal correlativity analysis is accordingly presented. In order to improve the efficiency of analysis, the gas sensors code rules which can express the spatial topological relations are sug- gested. The experiments indicate that methods presented in this article can effectively compensate the defects of methods based on a single gas sensor monitoring data. 展开更多
关键词 gas monitoring spatio-temporal correlativity analysis anomaly pattern identification ALGORITHM
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Spatio-temporal Variability of Soil Water at Three Seasonal Floodplain Sites: A Case Study in Tarim Basin,Northwest China 被引量:3
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作者 Sven GRASHEY-JANSEN Martin KUBA +2 位作者 Bernd CYFFKA müt HALIK Tayierjiang AISHAN 《Chinese Geographical Science》 SCIE CSCD 2014年第6期647-657,共11页
The floodplain -egetation of the Tarim River in Northwest China is strongly influenced by irrigated agriculture. The abstrac- tion of river water disturbs; the natural dynamics of the floodplain ecosystem. The human i... The floodplain -egetation of the Tarim River in Northwest China is strongly influenced by irrigated agriculture. The abstrac- tion of river water disturbs; the natural dynamics of the floodplain ecosystem. The human impact on the hydrological system by bank dams and the irrigation of cotton plantings have caused adverse changes of the Tarim River and its floodplains, so the current stocks of the typical Tugai vegetation show significant signs of degradation. Field studies of soils and statistical analysis of soil moisture data have shown that the vitality of the Tugai vegetation is primarily determined by its position to the riverbank and the groundwater. There exist complex interactions between soil hydrological conditions and the vitality of the vegetation. But the availability of water is not only influenced by the groundwater level and seasonal flood events. The spatial distribution of stocks at different states of vitality seems also to be decisively influenced by physical soil properties. Our results show that the water supply of plant communities is strongly in- fluenced by the soil texture. Spatial differences of soil moisture and corresponding soil water tensions may be the decisive factors for the zonafion of vegetation. Physical soil properties control the water retention and rising of capillary water from deeper soil layers and the phreatic zone and may supply the root systems of the phreatophytic vegetation with water. Keywords: soil moisture;soil texture; soil water tensions; Tarim River; water retention 展开更多
关键词 soil moisture soil texture soil water tensions Tarim River water retention
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Spatial-temporal variance of reclamation soil physical and chemical character in opencast mine region 被引量:2
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作者 HU Ye-cui LI Xin-ju +2 位作者 FANG Yu-dong LIU Xue-ran ZHONG Wei-jing 《Journal of Coal Science & Engineering(China)》 2009年第4期399-403,共5页
In order to study the effects of soil compaction, and soil physical and chemicalcharacteristics after land reclamation, selected lands that were reclaimed after 1, 2, 3, 4,and 5 a, respectively, in the Majiata Mine of... In order to study the effects of soil compaction, and soil physical and chemicalcharacteristics after land reclamation, selected lands that were reclaimed after 1, 2, 3, 4,and 5 a, respectively, in the Majiata Mine of the Shendong Open Pit; tested the effects ofsoil compaction; and collected soil samples from 5 different depths, which are 0-7.62,7.62-15.24, 15.24-22.86, 22.86-30.48, and 30.48-38.10 cm, respectively. The resultsshow that: Land reclamation leads to soil compaction. The lowest effect of soil compaction is in the top layer and the highest one at the depth of 20-30 cm; The bulk density of reclaimed soil is higher than that of undisturbed soil; this declines with the reclamation and nearly reaches the level of undisturbed soil after 5-year reclamation;The content of reclaimed soil nutrients is lower than that of undisturbed soil. The lowest one is inthe soil dumping site, which reaches the level of undisturbed soil after 5-year reclamation;The pH value of reclaimed soil is lower than that of undisturbed soil. The highest one isin the soil dumping site; this declines with the reclamation. 展开更多
关键词 opencast reclaimed soil soil characteristics spatial-temporal variation
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Spatial and Temporal Variability of Water Vapor Content during 1961-2011 in Tianshan Mountains,China 被引量:2
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作者 HU Wen-feng YAO Jun-qiang +1 位作者 HE Qing YANG Qing 《Journal of Mountain Science》 SCIE CSCD 2015年第3期571-581,共11页
Based on the climate factors data and surface vapor pressure (SVP) data of 44 weather stations in Tianshan Mountains during the years 1961-2011, this paper establishes a water vapor content (WVC) estimation model ... Based on the climate factors data and surface vapor pressure (SVP) data of 44 weather stations in Tianshan Mountains during the years 1961-2011, this paper establishes a water vapor content (WVC) estimation model according to the relationship between monthly WVC of radiosonde and corresponding SVP and analyzes the spatial and temporal variability of WVC and their causes. The results show that the WVC is linearly and negatively related to the elevation and longitude (Vertical zonality and Longitude zonality), while it was not linearly related to the latitude. The westerly wind, geographical situation and sea level elevation composed complex surface conditions to influence the spatial distribution of WVC in the Tianshan Mountains. The Mann-Kendall (M-K) statistical test shows a significant increasing trend in the mean annual WVC in Tianshan Mountains during 1961- 2011(P 〈 0.001), with a rate of 0.23 mm/decade, and indicates an abrupt turning point in 1985 (P.〈0.001). Correlation analysis shows that the WVC are significantly correlated to the temperature, especially during the winter, but the summer WVC are significantly correlated to the precipitation. In addition, the North Atlantic Oscillation Index (NAOI) and the Arctic Oscillation Index (AOI) are significantly correlated to the winter WVC in the Tianshan Mountains. As a new Microwave radiometric profilers (MWRPs) instrument, the MP- 3000A provides continuous, real-time and high temporal resolution atmospheric profiles up to 10 km. In order to monitor water vapor and atmosphere profiles in Tianshan Mountains, an MP-3000A was established in Urumqi (43.8°N, 87.58°N) in May 2008. The results indicated that the MP-3oooA was applicable to this area, and the evolutionary process of water vapor and the WVC peak values of MP- 3000A were a strong signal for rainstorm and flood forecasts for Urumqi and the Tianshan Mountains. 展开更多
关键词 Water vapor content Spatial variability Temporal variability Microwave radiometers Tianshan Mountains
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Spatio-temporal variability of periphytic protozoa related to environment in the Niyang River,Tibet,China 被引量:1
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作者 刘海平 叶少文 +6 位作者 杨学峰 郭传波 张惠娟 范丽卿 张良松 Sovan Lek 李钟杰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第3期489-500,共12页
The Niyang River, a main tributary of the Yarlung Zangbo River, is an important and typical plateau fiver ecosystem in Tibet, China. At present, few studies have focused on its aquatic living resources and fiver ecolo... The Niyang River, a main tributary of the Yarlung Zangbo River, is an important and typical plateau fiver ecosystem in Tibet, China. At present, few studies have focused on its aquatic living resources and fiver ecology. In this study, the composition, abundance, and diversity of periphytic protozoa were investigated across four seasons from 2008 to 2009 to better understand their spatio-temporal patterns and relationship to the environment. Our investigation shows that periphytic protozoa in the Niyang River contained 15 genera, belonged to Tubulinea, Alveolata, Discosea and Rhizaria, Alveolata possessed most genera, up to nine, with highest share in abundance, exceeding 50%, Difflugia and Glaucoma were dominant genera. Moreover, four diversity indices of periphytic protozoa, including species richness, total abundance, Shannon-Wiener diversity index and Pielou's evenness index, displayed a significant descending trend as the seasons continued, in the order of winter, spring, summer and autumn; with a significant difference existing between winter and summer (or autumn) for Shannon-Wiener diversity index and species richness (P〈0.05). Four of these diversity indices also presented a V-shaped pattern between the upper middle course of the Niyang River and the confluence of the Niyang River and Yarlung Zangbo River, with the lowest value occurred in the middle course of the Niyang River. However, no significant variation was found through the Niyang River (P〉0.05). In addition, canonical correlation analysis (CCA) shows that the densities of Difflugia, Glaucomais, Enchelydium, Cyphoderia, and Enchelys correlate with water temperature, alkalinity, hardness, pH, and dissolved oxygen, respectively. Lastly, the relationship between periphytic protozoa diversity and the environmental factors of the Niyang River can be predicted using classification and regression trees (CART) annalysis, which suggests that the total abundance and Shannon-Wiener diversity index would be higher when the elevation is above 3 308 m. On the other hand, the Shannon-Wiener diversity index and Pielou's evenness index would be lower when pH and ammoniacal nitrogen have lower or higher values. Finally yet importantly, close attention should be paid to periphytic protozoa and its environment to ensure sustainable development of the Niyang River ecosystem. 展开更多
关键词 Tibetan Plateau Niyang River periphytic protozoa ENVIRONMENT spatio-temporal dynamic
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Temporal variability of temperature-nitrate relationship in a coastal region
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作者 殷建平 林立 +1 位作者 王友绍 杜建伟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第4期879-885,共7页
The inverse relationship between nitrate and temperature(N-T relationship) has been used to estimate new production from remotely sensed sea surface temperature at the regional or global scale of oceans. This study ai... The inverse relationship between nitrate and temperature(N-T relationship) has been used to estimate new production from remotely sensed sea surface temperature at the regional or global scale of oceans. This study aimed to develop a time-series model of the N-T relationship from automated, continuous hourly observations over two years on the coast of Halifax, Canada. The model demonstrated time-series variability of the N-T relationship at a coastal station on the Nova Scotia Shelf, with adjusted R 2 =0.999 4 and RMSE=0.025 7. The maximum residual value was 0.077. The annual temperature variations described a sine curve, and daily, weekly, and monthly variations fluctuated within the normal ranges, controlled by the local climate. The annual variation of nitrate concentration formed nearly a sine curve. Heavy or longlasting rainfall increased nitrate concentration by 4 to 30-fold in 24 h, and then the increased nitrogen was quickly depleted by phytoplankton growth in 10 to 48 h. In general, biological activity was a key factor in causing nitrate concentration change, dependent mainly on seawater temperature. The power function of the N-T relationship observed in our study area could be used to quickly estimate sea surface nitrate concentration, in combination with temperature data obtained by remote sensing. 展开更多
关键词 sea surface temperature sea surface nitrate nitrate and temperature (N-T relationship) model Halifax Canada
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Investigation of the Macroscopic Anomalies before and after the M8. 0 Wenchuan Earthquake
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作者 Zhang Xiaotao Zhang Yongxian Xu Dunhuan 《Earthquake Research in China》 2010年第1期48-69,共22页
The macroscopic anomalies before and after the May 12,2008 Wenchuan M8. 0 earthquake were collected and analyzed in this paper. The credible anomalies occurring from February 1 to June 10,2008 were treated as macrosco... The macroscopic anomalies before and after the May 12,2008 Wenchuan M8. 0 earthquake were collected and analyzed in this paper. The credible anomalies occurring from February 1 to June 10,2008 were treated as macroscopic anomalies,and their space-time distribution was studied. The research indicates that in time distribution,the number of macroscopic anomalies peaked before the earthquake,and these peak values appeared twice after the earthquake. In space distribution,the distribution of macroscopic anomalies before the earthquake was the same as that after the earthquake. In this paper,the mechanism of occurrence of macroscopic anomalies and the role of macroscopic anomalies in forecasting earthquake were also discussed. 展开更多
关键词 Wenchuan earthquake Macroscopic anomaly Statistical analysis Space-time distribution
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COST:Coding over Spatial-Temporal Diversity for Low-Duty-Cycle WSNs
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作者 闫宇博 杨盘隆 +2 位作者 张磊 何源 郭得科 《China Communications》 SCIE CSCD 2011年第1期35-42,共8页
In low-duty-cycle wireless sensor networks,designers have to cope with unreliable links and limited communication capacity.In this work,we propose COST,a coding scheme that leverages spatial-temporal diversity to achi... In low-duty-cycle wireless sensor networks,designers have to cope with unreliable links and limited communication capacity.In this work,we propose COST,a coding scheme that leverages spatial-temporal diversity to achieve higher energy efficiency and lower delay of packet transmissions.We particularly address long sleeping intervals in low-duty-cycle networks by exploiting multi-path diversity.Specifically,we propose to employ an erasure-coding scheme to improve reliability.With respect to energy efficiency and delivery timeliness,we formulate the problem in optimal allocation of coded blocks over multiple paths,which is then proved to be NP-hard.We further propose a near-optimal algorithm to solve the allocation problem.Through extensive simulations,we evaluate the impact of network parameters and demonstrate the effectiveness of our proposal. 展开更多
关键词 low-duty-cycle MULTI-PATH CODING wireless sensor network
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