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Change Trends of Accumulated Temperature and Effects on Agricultural Production in Shenyang during Recent 58 Years 被引量:1
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作者 YANG Li-li LIU Feng-zhi JIANG Miao 《Meteorological and Environmental Research》 CAS 2011年第1期35-38,42,共5页
[Objective] The aim was to study the change trend of accumulated temperature in Shenyang in recent 58 years, as well as its effect on agricultural production. [Method] Based on the surface temperature data in Shenyang... [Objective] The aim was to study the change trend of accumulated temperature in Shenyang in recent 58 years, as well as its effect on agricultural production. [Method] Based on the surface temperature data in Shenyang, the change trends of ≥0 ℃ and ≥10 ℃ accumulated temperature in Shenyang in recent 58 years were analyzed by means of climatic statistics method, and the effects of accumulated temperature variation on agricultural production were discussed. [Result] In recent 58 years, the first day with temperature ≥0 ℃ advanced 10 d, and the last day put off slightly, while sustained days prolonged 13 d, and ≥0 ℃ accumulated temperature increased by 343 ℃·d; meanwhile, the first day with temperature ≥10 ℃ advanced 9 d, and the last day put off 8 d, while sustained days prolonged 16 d, and ≥10 ℃ accumulated temperature increased by 370 ℃·d; compared with the first 20 years, sustained days with temperature ≥0 ℃ and ≥10 ℃ prolonged 9 d in the last 20 years, and ≥0 ℃ and ≥10 ℃ accumulated temperature increased by 196 and 202 ℃·d, respectively. In addition, the increase of heat resources affected agricultural production in Shenyang. [Conclusion] The study could provide theoretical foundation for grasping heat resources variation and adjusting agriculture distribution. 展开更多
关键词 Shenyang Accumulated temperature Climatic tendency change trend China
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Preliminary Studies on Evaluation and Change Trends of Dominant Components in New Types of Tobacco Sheets by Thick Pulp Process
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作者 Hao SHU Xiangbing TANG +8 位作者 Ziwei WANG Xinge ZHANG Wanxia WANG Dan LI Qunshan YAN Tongfu SU Yanqiu JING Song GAO Bin XIONG 《Agricultural Biotechnology》 CAS 2022年第6期126-129,133,共5页
[Objectives]This study was conducted to deeply understand the effects of production process on the quality of new types of tobacco sheets with different flavors.[Methods]Based on the pilot production process of thick ... [Objectives]This study was conducted to deeply understand the effects of production process on the quality of new types of tobacco sheets with different flavors.[Methods]Based on the pilot production process of thick pulp method,four different flavors of tobacco sheets were sampled at several links in the production process,for the detection of the contents of the main components in the samples,including propylene glycol,glycerol,menthol and glyceryl triacetate,so as to explore the change trends of various components in the thick pulp process.[Results]The change laws of propylene glycol and glycerol contents had a very high similarity,showing a trend of first decreasing and increasing then.The changes of menthol content and glyceryl triacetate content were greatly affected by the specific flavor formula.As one of the indexes of the new tobacco evaluation system,the alcohol-to-ester ratio data need to be further improved in the actual production and application process.[Conclusions]This study provides basic data support for improving the quality of tobacco sheets. 展开更多
关键词 New tobacco product Thick pulp process Heat-not-burn tobacco product Tobacco sheets Changing trend
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Changes of coastline and tidal flat and its implication for ecological protection under human activities: Take China’s Bohai Bay as an example
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作者 Yong Li Ming-zheng Wen +3 位作者 Heng Yu Peng Yang Fei-cui Wang Fu Wang 《China Geology》 CAS CSCD 2024年第1期26-35,共10页
The change processes and trends of shoreline and tidal flat forced by human activities are essential issues for the sustainability of coastal area,which is also of great significance for understanding coastal ecologic... The change processes and trends of shoreline and tidal flat forced by human activities are essential issues for the sustainability of coastal area,which is also of great significance for understanding coastal ecological environment changes and even global changes.Based on field measurements,combined with Linear Regression(LR)model and Inverse Distance Weighing(IDW)method,this paper presents detailed analysis on the change history and trend of the shoreline and tidal flat in Bohai Bay.The shoreline faces a high erosion chance under the action of natural factors,while the tidal flat faces a different erosion and deposition patterns in Bohai Bay due to the impact of human activities.The implication of change rule for ecological protection and recovery is also discussed.Measures should be taken to protect the coastal ecological environment.The models used in this paper show a high correlation coefficient between observed and modeling data,which means that this method can be used to predict the changing trend of shoreline and tidal flat.The research results of present study can provide scientific supports for future coastal protection and management. 展开更多
关键词 SHORELINE Tidal flat Erosion deposition patterns Changing trend Ecological protection Human activity Linear regression model Inverse distance weighing method Prediction Bohai Bay
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Metropolitan resources efficiencies,change trends and causes in China under the goal to build an international metropolis 被引量:4
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作者 GUO Tengyun HE Shujin DONG Guanpeng 《Journal of Geographical Sciences》 SCIE CSCD 2011年第4期746-756,共11页
The metropolitan resources comprehensive efficiencies (also called comprehensive technical efficiency, short for CTE, thereafter), change trends and causes are investigated using DEA and Malmquist index models, resp... The metropolitan resources comprehensive efficiencies (also called comprehensive technical efficiency, short for CTE, thereafter), change trends and causes are investigated using DEA and Malmquist index models, respectively, in China during the period 1990–2006. Firstly, the DEA model results show that the metropolitan CTE was just fair to middling with the characteristics of almost declining from the Eastern Coastal to Western China, and only few metropolises were DEA efficient. Secondly, the results also show that the PTE was correlated with the urban population sizes of metropolises negatively, and the SE correlated positively with the urban population sizes of metropolises in 1990, 2000 and 2006, that is, with urban population sizes getting larger the corresponding PTE was decreasing accordingly, and the SE was increasing consequently and the increasing rate was smaller with the scale increase. Thirdly, the influencing factors of metropolitan efficiency were SE and PTE in 1990 and 2000, respectively. But the PTE became the predominant influencing factor with the rapid expansions of built-up areas and population scales of metropolises in 2006. Fourthly, the Malmquist index results show that the CTE change trends were increasing weakly, the technological change trends were declining, and the TFP change trends were declining obviously during 1990–2006, in which they were all increasing during the sub-period 1990–2000, and all decreasing during the sub-period 2000–2006. Fifthly, the Malmquist index results also demonstrate that the CTE change trend was increasing weakly in the Eastern Coastal China, declining in Central China, and declining evidently in Western China. And with the urban population size increasing the increasing trends of SE became weaker and weaker. And the main causes for the CTE being not too high and its change trends and TFP change trends being increasing weakly lie mainly in the technological degeneracy and PTE change trends declining significantly during 2000–2006. Finally, the analyses show that the China’s metropolitan population boom and the rapid spread of built-up area had really caused their resources efficiency losses. 展开更多
关键词 DEA Malmquist index models resources efficiency change trend CAUSES METROPOLIS China
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The Influence of the Changes in Social Trends of Thought in Japan
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作者 Cui Shiguang is a Research Professor at Institute for Japanese Studies of China Academy of Social Sciences. 《Contemporary International Relations》 2003年第11期33-38,共6页
The social trend of thought is the trend of thought that is of extensive influence formed in a certain period of time in a given society. It o-riginates from the changes in international environment and domestic socia... The social trend of thought is the trend of thought that is of extensive influence formed in a certain period of time in a given society. It o-riginates from the changes in international environment and domestic social situation, reflecting the interests and demands of a given group of people and producing a great influence on the foreign and domestic policies and the future trend of the society. One prominent feature of 展开更多
关键词 of in The Influence of the changes in Social trends of Thought in Japan that
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Age Structure and Change Trend of Tobacco Farmers:A Case Study of Shashi Town,Liuyang City,Hunan Province
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作者 Jianwen WANG Liangjiao LIU +3 位作者 Zhengguang ZHAI Zhiqiang DENG Tao ZHU Sihan HUANG 《Asian Agricultural Research》 2023年第8期8-15,共8页
Taking the tobacco-growing area of Shashi Town,Liuyang City as the object,the number of registered,newly added and resigned tobacco farmers in each year,average age,number and proportion of tobacco farmers of differen... Taking the tobacco-growing area of Shashi Town,Liuyang City as the object,the number of registered,newly added and resigned tobacco farmers in each year,average age,number and proportion of tobacco farmers of different ages,number and proportion of tobacco farmers born in different eras,as well as planting scale and planting history of flue-cured tobacco in the last 10 years were analyzed statistically.The results showed that the number of tobacco farmers in Shashi Town showed a rapid decline trend from 2012 to 2018,while the average age continuously increased,and the average planting scale rose in a wave like way.From 2019 to 2021,the decline rate of the number of tobacco farmers slowed down,and the average planting scale continuously increased,while the aging of tobacco farmers accelerated.Meantime,the birth years of tobacco farmers were further concentrated in the 1960s,and they were mainly at the age of 50-59.The tobacco industry in Shashi Town of Liuyang City is facing the crisis of aging tobacco farmers and no successor of flue-cured tobacco planting,and it is predicted that the next 5-10 years will continue the change trend from 2019 to 2021. 展开更多
关键词 Tobacco farmers Number Birth year Average age Planting years change trend Prediction
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Climate change trend and its effects on reference evapotranspiration at Linhe Station, Hetao Irrigation District 被引量:5
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作者 Xu-ming WANG Hai-jun LIU +1 位作者 Li-wei ZHANG Rui-hao ZHANG 《Water Science and Engineering》 EI CAS CSCD 2014年第3期250-266,共17页
Linhe National Meteorological Station, a representative weather station in the Hetao Irrigation District of China, was selected as the research site for the present study. Changes in climatic variables and reference e... Linhe National Meteorological Station, a representative weather station in the Hetao Irrigation District of China, was selected as the research site for the present study. Changes in climatic variables and reference evapotranspiration (ET0 ) (estimated by the Penman-Monteith method) were detected using Mann-Kendall tests and Sen's slope estimator, respectively. The authors analyzed the relationship between the ET0 change and each climatic variable's change. From 1954 to 2012, the air temperature showed a significant increasing trend, whereas relative humidity and wind speed decreased dramatically. These changes resulted in a slight increase in ETo. The radiative component of total ET0 increased from 50% to 57%, indicating that this component made a greater contribution to the increase in total ETo than the aerodynamic component, especially during the crop growing season (from April to October). The sensitivity analysis showed that ETo in Hetao is most sensitive to mean daily air temperature (11.8%), followed by wind speed (-7.3%) and relative humidity (4.8%). Changes in sunshine duration had only a minor effect on ET0 over the past 59 years. 展开更多
关键词 climatic variables reference evapotranspiration change trend Mann-Kendall test sensitivity analysis
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Trend of Salt Lake Changes in the Background of Global Warming and Tactics for Adaptation to the Changes 被引量:12
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作者 ZHENGMianping QIWen +2 位作者 JIANGXianfeng ZHAOYuanyi LIMinghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第3期795-807,共13页
Salt lakes are a mirror of climatic changes and provide holographic records of environmental changes of lakes. According to a study of geological hazards in typical salt lake areas in China and other regions, the auth... Salt lakes are a mirror of climatic changes and provide holographic records of environmental changes of lakes. According to a study of geological hazards in typical salt lake areas in China and other regions, the authors explain how geological hazards in salt lake areas are caused by natural agents and how humans can seek benefits, avoid hazards and reduce losses on the premise that they have monitored and mastered the trend of salt lake changes in advance and even can store flood and recharge water in lakes and extract saline resources. The climate in western China is probably turning from warm-dry to warm-moist. The authors analyze the change trend of salt lakes sensu lato (with salinity≥0.3 wt% (NaCl)eq) and salt lakes sensu stricto (with salinity ≥3.5 wt% (NaCl)eq) in China in such climatic conditions and distinguish three types of salt lake areas (i.e. lake water rising type, lake water falling type and lake water rising and unstable type) according to the characteristics of lake water rising and shrinking. In order to conform to the climatic and lake changes in China's salt lake areas, the authors propose to add and improve hydrological and meteorological observation stations and integrate observations with remote sensing monitoring in important salt lake areas and set up multidisciplinary and interdepartmental basic projects to monitor and study recent climatic and environmental changes in salt lake areas of western China. Moreover, it is necessary to build additional flood-control and drought-preventing water conservancy facilities in key salt lake areas and work out measures for ecological protection in salt lake areas. Full consideration should be given to the influence of flooding when building saltfields and implementing capital projects. 展开更多
关键词 global warming geological hazard of salt lake trend of salt lake change salt lake water rising and shrinking types tactics for adaptation to change
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Analysis of Changing Characteristics and Trends of Temperature and Precipitation in Yanshi City in Recent 50 Years
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作者 Zhang Yuan 《Meteorological and Environmental Research》 CAS 2015年第10期1-4,共4页
Based on meteorological observation data of temperature and precipitation in Yanshi City from 1961 to 2010, annual and interdecadal variations of annual average temperature, annual average maximum temperature, annual ... Based on meteorological observation data of temperature and precipitation in Yanshi City from 1961 to 2010, annual and interdecadal variations of annual average temperature, annual average maximum temperature, annual average minimum temperature, and annual average pre- cipitation in Yanshi City in recent 50 years were analyzed, and then M-K test of changing trend of annual average temperature was conducted. The results showed that from 1961 to 2010, annual average temperature, annual average maximum temperature and annual average minimum tempera- ture showed a significantly increasing trend in Yanshi City, rising by 0.30, 0.20 and 0.50 ~(3/10 a respectively. Annual average temperature was the lowest in the 1970s and the highest in 2000 -2010. There was a sudden change in annual average temperature in 1995. In the 50 years, annual av- erage precipitation in Yanshi City increased by 1.8 mm/10 a, but the increase was not significant. The minimum of annual average precipitation 511.3 mm appeared in the 1960s, while the maximum 553.2 mm appeared in 2000 -2010. 展开更多
关键词 Temperature Changing trend PRECIPITATION M-K test Yanshi City China
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Variation Characteristics and Trends of Temperature and Evaporation in Huanren County in Recent 60 Years
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作者 Zhao Lei Ji Qi +1 位作者 Li Ji Wang Junchao 《Meteorological and Environmental Research》 CAS 2016年第3期7-9,共3页
Based on the data of daily average temperature and evaporation in Huanren County from 1953 to 2012, the changing characteristics and trends of temperature and evaporation were analyzed by using climatic tendency rate ... Based on the data of daily average temperature and evaporation in Huanren County from 1953 to 2012, the changing characteristics and trends of temperature and evaporation were analyzed by using climatic tendency rate and sliding Ttest method. The results showed that annual av- erage temperature in Huanren County showed a significant increasing trend in recent 60 years, and its linear tendency rate was 0.26 ℃/10 a. Tem- perature increase was in other seasons except for summer. There was a sudden change in annual average temperature in 1987, and winter average temperature changed suddenly in 1969 and 1985, while there were no sudden changes in average temperature in other seasons. Annual average evaporation also decreased, and its linear trend rate was -8.19 mm/10 a; average evaporation tended to decrease in spring and summer and in- creased in autumn and winter. In a word, the climate tended to be warm and dry in Huanren County. 展开更多
关键词 TEMPERATURE EVAPORATION Changing trend Mutation detection Huanren County China
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Simulation of Change Trend of Drought in Shaanxi Province in Future Based on PRECIS Model
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作者 LI Ming-juan ZHAO Kui-feng 《Meteorological and Environmental Research》 CAS 2011年第2期6-9,共4页
[Objective] The aim was to predict the change trend of drought in Shaanxi Province in future. [Method] Based on the regional climate model PRECIS from Hadley Climate Center, British Meteorological Bureau, taking preci... [Objective] The aim was to predict the change trend of drought in Shaanxi Province in future. [Method] Based on the regional climate model PRECIS from Hadley Climate Center, British Meteorological Bureau, taking precipitation anomaly percentage as assessment index, the change trend of drought in Shaanxi Province in reference years (1971-1990) was simulated, and the change trend of drought in Shaanxi Province from 2071 to 2100 was predicted. [Result] The simulated value of drought frequency in reference years could simulate the distribution of drought well, namely drought frequency was high in the north and low in the south; annual mean frequency of drought above second grade decreased gradually from north to south in future, and it was the highest in northern Shaanxi (above 4 times) and lowest in southern Shaanxi (below 2.5 times); drought frequency in future went down in northern Shaanxi from southern Yulin to Yan’an, eastern Guanzhong (including Weibei) and the west of southern Shaanxi, while it went up in the north of northern Shaanxi, Qinling Mountains and Shangluo region in western Guanzhong. [Conclusion] The study could provide theoretical references for the research on the change trend of drought in Shaanxi Province in future. 展开更多
关键词 PRECIS DROUGHT change trend SHAANXI China
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Analysis on Change Tendency of the Precipitation Resource during Growth Period of the Conventional Crops in Plain Area before Taihang Mountains
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作者 Suqing Han Shijing Jia 《Meteorological and Environmental Research》 CAS 2013年第2期49-52,共4页
[Objective] The aim was to study change tendency of the precipitation resource during growth period of the conventional crops in plain area before Taihang Mountains. [ Method] Based on daily precipitation data at Shij... [Objective] The aim was to study change tendency of the precipitation resource during growth period of the conventional crops in plain area before Taihang Mountains. [ Method] Based on daily precipitation data at Shijiazhuang meteorological station in recent 51 years, average rainfall dudng growth periods of the 9 kinds of conventional crops was obtained. Precipitation tendency dudng growth periods of the 9 kinds of conventional crops in plain area before Taihang Mountains was analyzed by Mann-Kendall nonparametric test. [ Result] Seen from rainfall during growth pedods of the different crops, rainfall was the least during the growth period of winter wheat, followed by summer corn. Rainfall during growth peri- ods of the cotton, oil plant, vegetable, fruit tree, potato, rice and legumes was more. Under different guaranteed rates, precipitation change also had difference. Rainfall change during growth periods of the wheat and corn was bigger, and rainfall change during growth period of the rice was smaller. Change degree of the precipitation during growth periods of the cotton, oil plant, vegetable, fruit tree and legumes was equivalent, while precipitation change during growth period of the potato was the biggest. Seen from change tendency of the precipitation during growth periods of the different crops, precipitation in the growth period of winter wheat was increasing at a speed of 0.62 mm/a. However, precipitation in growth periods of the other crops had a decreasing tendency. Precipitation in the growth periods of summer corn and legumes decreased at the same speed which was 2.11 mm/a, while precipitation in growth periods of the cotton, oil plant, vegetable, fruit tree, potato and rice decreased insignificantly. [ Con dusion] The study laid foundation for determination of the agricultural irrigation water and provided theoretical reference for regional agricultural water-saving. 展开更多
关键词 Precipitation resource Conventional crops Growth period change trend Plain area before Taihang Mountains China
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Spatial / Temporal Features of Antarctic Climate Change
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作者 葛玲 梁佳兴 陈毅良 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1996年第3期375-382,共8页
Bused on January 1962-October 1993 mean value series of monthly mean temperature anomalies of 16 Antarctic stations on 10 standard isobanc surfaces from the surface to the 30 hPa,long term trends and periodic features... Bused on January 1962-October 1993 mean value series of monthly mean temperature anomalies of 16 Antarctic stations on 10 standard isobanc surfaces from the surface to the 30 hPa,long term trends and periodic features of climate changes from the troposphere to the lower stratosphere over the Antarctic region are investigated by maximum entropy power spectrum analysis,and the relation between climate change of the stratosphere (troposphere) and tolal ozone (southern 500 hPa circulation) is discussed. 展开更多
关键词 ANTARCTIC Climate change: Long term trend Periodicity Total ozone
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Analysis on Temporal-spatial Distribution and Change Trend of the Temperature in Beibei District
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作者 ZHANG Shuang LI Jia-qi +3 位作者 WANG Zhi-hui LI Guang-bing WAN Min PENG Chao 《Meteorological and Environmental Research》 2012年第10期1-4,共4页
[ Objective] The research aimed to analyze temporal-spatial distribution and change trend of the temperature in Beibei District. [ Method] Based on temperature observation data at 6 ground meteorological observatories... [ Objective] The research aimed to analyze temporal-spatial distribution and change trend of the temperature in Beibei District. [ Method] Based on temperature observation data at 6 ground meteorological observatories of Beibei District from 1951 to 2010, EOF and linear trend method were used to analyze temporal-spatial distribution and change characteristics of the temperature in Beibei District in recent 60 years. [ Result] Tem- perature in Beibei District in recent 60 years overall presented rise trend, and average rise velocity was 0.045 ~C/10 a. Temperature rise in autumn was the most obvious, while summer temperature presented decline trend. Average temperature presented gradual rise trend from January to July and gradual decrease trend from August to December. Seen from spatial distribution, temperature in the whole district was higher in the west and lower in the middle. Abnormal spatial distribution of the average temperature in the whole district mainly had consistent higher (lower) type, south- north reverse type and east-west reverse type. [ Condusionl The research provided theoretical basis for effective disaster prevention and reduction in the zone. 展开更多
关键词 TEMPERATURE Temporal and spatial distribution change trend Beibei District China
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Analysis on Change Trend and Influencing Factors of Natural Resource Utilization of Community Farmers around the Habitat of Giant Pandas
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作者 Qing Qin Xiao Zhou +3 位作者 Shuo Wang Shuihua Cai Yan Dong Jian Qiu 《Journal of Environmental Protection》 2022年第6期437-448,共12页
The habitat of giant pandas borders the living areas of farmers in surrounding communities. Due to the low level of economic development and resource used method, the life of community farmers depends on the natural r... The habitat of giant pandas borders the living areas of farmers in surrounding communities. Due to the low level of economic development and resource used method, the life of community farmers depends on the natural resources of the habitat of giant pandas. Analyzing the natural resource utilization of farmers in communities around the habitat of giant pandas is conducive to formulating more reasonable management policies and protecting the habitat of giant pandas more effectively. Based on the field survey data, this paper classifies the main ways of community farmers using the natural resources of the habitat of giant pandas, counts the quantity of resources used and analyzes their change trends. On this basis, this paper selects indicators, constructs a model and analyzes the main influencing factors affecting the natural resources utilization of community farmers from three aspects: the individual characteristics of household heads, the family characteristics of community farmers and the residence characteristics of community farmers. 展开更多
关键词 Natural Resource Method of Utilization change Trend Influencing Factors The Habitat of Giant Pandas
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The Trends of Globalization and Digitalization are Changing the Market Contexts
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作者 Sunil Bharti Mittal 《China's Foreign Trade》 2016年第5期20-21,共2页
We know that SME’s that trade online grow faster and create more jobs than those that only operate in their domestic markets.The Internet is breaking down many traditional barriers to global trade,but there is still ... We know that SME’s that trade online grow faster and create more jobs than those that only operate in their domestic markets.The Internet is breaking down many traditional barriers to global trade,but there is still much governments can do to speed and enable SME digitization and ecommerce.The opportunity is huge at 展开更多
关键词 The trends of Globalization and Digitalization are Changing the Market Contexts
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Correlation analysis between the Aral Sea shrinkage and the Amu Darya River 被引量:1
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作者 WANG Min CHEN Xi +6 位作者 CAO Liangzhong KURBAN Alishir SHI Haiyang WU Nannan EZIZ Anwar YUAN Xiuliang Philippe DE MAEYER 《Journal of Arid Land》 SCIE CSCD 2023年第7期757-778,共22页
The shrinkage of the Aral Sea,which is closely related to the Amu Darya River,strongly affects the sustainability of the local natural ecosystem,agricultural production,and human well-being.In this study,we used the B... The shrinkage of the Aral Sea,which is closely related to the Amu Darya River,strongly affects the sustainability of the local natural ecosystem,agricultural production,and human well-being.In this study,we used the Bayesian Estimator of Abrupt change,Seasonal change,and Trend(BEAST)model to detect the historical change points in the variation of the Aral Sea and the Amu Darya River and analyse the causes of the Aral Sea shrinkage during the 1950–2016 period.Further,we applied multifractal detrend cross-correlation analysis(MF-DCCA)and quantitative analysis to investigate the responses of the Aral Sea to the runoff in the Amu Darya River,which is the main source of recharge to the Aral Sea.Our results showed that two significant trend change points in the water volume change of the Aral Sea occurred,in 1961 and 1974.Before 1961,the water volume in the Aral Sea was stable,after which it began to shrink,with a shrinkage rate fluctuating around 15.21 km3/a.After 1974,the water volume of the Aral Sea decreased substantially at a rate of up to 48.97 km3/a,which was the highest value recorded in this study.In addition,although the response of the Aral Sea's water volume to its recharge runoff demonstrated a complex non-linear relationship,the replenishment of the Aral Sea by the runoff in the lower reaches of the Amu Darya River was identified as the dominant factor affecting the Aral Sea shrinkage.Based on the scenario analyses,we concluded that it is possible to slow down the retreat of the Aral Sea and restore its ecosystem by increasing the efficiency of agricultural water use,decreasing agricultural water use in the middle and lower reaches,reducing ineffective evaporation from reservoirs and wetlands,and increasing the water coming from the lower reaches of the Amu Darya River to the 1961–1973 level.These measures would maintain and stabilise the water area and water volume of the Aral Sea in a state of ecological restoration.Therefore,this study focuses on how human consumption of recharge runoff affects the Aral Sea and provides scientific perspective on its ecological conservation and sustainable development. 展开更多
关键词 Aral Sea shrinkage recharge runoff Amu Darya River Syr Darya River multifractal detrend cross-correlation analysis(MF-DCCA) Bayesian Estimator of Abrupt change Seasonal change and Trend(BEAST) Central Asia
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Characteristics of Ambient Air Quality in the Central Urban Area of Western Guizhou in the Past Five Years 被引量:1
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作者 Shihua JIANG Zaixiang CHI +3 位作者 Kai XU Lijuan LIU Zijiang YANG Changwen CHEN 《Meteorological and Environmental Research》 CAS 2020年第6期23-30,共8页
Air is an important condition for human activities and survival,and its quality is closely related to the quality of life and level of health for the people.In recent years,the problem caused by air quality has become... Air is an important condition for human activities and survival,and its quality is closely related to the quality of life and level of health for the people.In recent years,the problem caused by air quality has become one of the main problems that endanger human health and restrict economic development,which has been widely concerned.In this paper,the air quality status and its changing trend were analyzed by using the methods of the comprehensive index of ambient air quality and Spearman s rank correlation coefficient,based on the hourly pollutant concentration data of five national ambient air quality monitoring stations in the central urban area of Liupanshui City,Guizhou Province from January 1,2015 to December 31,2019.The results showed that the concentration of air pollutants in the atmosphere in the past five years showed a downward trend in the central urban area of Liupanshui City.During 2018-2019,the air quality has been up to the standard for two consecutive years,and it was developing to a higher quality direction.The air quality was better in summer half year than in winter half year.In one year,the air quality was the best in June and the worst in February.The air quality was the best at 07:00 and the worst at 21:00 every day.The air quality in the east and the west of the city was better than that in the middle.In most years,the activities,making and burning paper to resemble money as an offering sacrifices to gods or ancestors in Zhongyuan Festival,caused serious pollution. 展开更多
关键词 Air quality Pollution concentration Spearman s rank correlation coefficient change trends
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Study on the Variation Characteristic of Precipitation in Liaoning Province in Recent 48 Years 被引量:4
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作者 ZHANG Hai-na GAO Jie 《Meteorological and Environmental Research》 CAS 2011年第1期5-6,共2页
[Objective] The aim was to study the variation characteristic of precipitation in Liaoning Province in recent 48 years. [Method] According to monthly precipitation data from meteorological observation station in Liaon... [Objective] The aim was to study the variation characteristic of precipitation in Liaoning Province in recent 48 years. [Method] According to monthly precipitation data from meteorological observation station in Liaoning Province from 1961 to 2008, the variation characteristic of precipitation in Liaoning was analyzed by means of one-dimensional linear estimation, 5-year moving average and wavelet transform method in our paper. [Result] Annual mean precipitation in Liaoning from 1961 to 2008 showed decrease trend on the whole, and there was great difference in variation in each season; there was more rainfall in 1960s, 1970s and 1990s and less rainfall in 1980s; spring precipitation showed increase trend on the whole, with great annual variation, while precipitation in other seasons reduced; the main fluctuation period of precipitation was 7-9 years which included the shorter variation period of 2-3 years. [Conclusion] The study could provide scientific references for the rational utilization of water resources, disaster prevention and reduction in Liaoning Province. 展开更多
关键词 PRECIPITATION change trend Characteristic analysis China
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Child Malnutrition In China-Present Status and Changing Trend 被引量:1
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作者 CHANG YING XIAN ZU-DE +3 位作者 HE WU CHANG SU-YING MA HAI-JIANG AND CHEN CHUN-MING(Institute of Nutrition and Food Hygiene, 29 Nan Wei Road Beijing 100050, China, State Statistics Bureau, Beijing, China,Chinese Academy of Preventive Medicine,27 Nan Wei Road Bei 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1996年第2期164-180,共17页
Halving the malnutrition of under five of years has been set as one of the goals to be achieved by the year of 2000 by Chinese government. So it is important to know the present status of child malnutrition and its tr... Halving the malnutrition of under five of years has been set as one of the goals to be achieved by the year of 2000 by Chinese government. So it is important to know the present status of child malnutrition and its trend of changing, in order to predict the possible outcome of the achievement of the goal. According to the Child Survey carried out by the State Statistic Bureau (SSB) in 26 provinces and autonmous regions and 3 municipalities in 1992, the prevalence of malnutrition of under five was: moderate and severe underweight, stunting and wasting were 17.9%, 34.7% and 4.7% respectively. But there are significant differences among urban and rural children and between different provinces. The highest prevalence rate usually occurred in the second year of life of the children, and this may be the result of inadequate weaning food provided to the children. As compared with the data collected in 1987 by SSB in 9 provinces and autonomous regions, an impressive improvement in underweight has occurred within these 5 years. The average declined prevalence was 20.5%. It is specially true for urban children. To stunting, there was also improvement for urban children but not in the rural, resulting and over all increasing of prevalence by 5.9%. To wasting, the prevalence for urban children was low and remained at the same level while there was some what increase in the rural. So, according to these results, with constant economic development and more attempt made in areas and groups at risk, the goal to decrease malnutrition in half in terms of underweight could be reached by the year of 2000 展开更多
关键词 In WHO Child Malnutrition In China-Present Status and Changing Trend
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