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Annual variation of adult survival of a south-temperate House Wren population in Argentina
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作者 Gustavo J.Fernandez Mariana E.Carro Paulo E.Llambías 《Avian Research》 SCIE CSCD 2024年第2期229-237,共9页
Identifying factors affecting the survival of individuals is essential for understanding the evolution of life-history traits and population dynamics.Despite numerous studies on this subject in north-temperate environ... Identifying factors affecting the survival of individuals is essential for understanding the evolution of life-history traits and population dynamics.Despite numerous studies on this subject in north-temperate environments,there is a lack of equivalent studies at similar latitudes in the south.Here,we used a 14-year dataset of capture,banding,and resighting to estimate the annual variation in the apparent adult survival probability of a south-temperate population of House Wrens(Troglodytes aedon bonariae).We evaluated temporal variation in sur-vival and the effect of environmental(climatic)and demographic variables(adult abundance,total number of fledglings produced during each breeding season)on survival estimators.We found that the probability of adult survival decreased as the abundance of breeding adults increased.This density-dependent effect could be related to the resident lifestyle of southern House Wrens,which could determine an intense competition for territories and resources that ultimately would affect their survival. 展开更多
关键词 annual variation CJS DENSITY-DEPENDENCE SURVIVAL Troglodytes aedon bonariae
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Horizontal Distribution and Annual Variations of Fecal Coliform Bacteria in Luoyuan Bay 被引量:2
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作者 蔡雷鸣 《Marine Science Bulletin》 CAS 2010年第1期48-58,共11页
Fecal Coliform Bacteria (FCB) of marine waters was monitored in Luoyuan Bay from January, 2003 to December, 2005. The results showed that number of FCB in marine water samples ranged from no detection ( 〈2 cfu/100... Fecal Coliform Bacteria (FCB) of marine waters was monitored in Luoyuan Bay from January, 2003 to December, 2005. The results showed that number of FCB in marine water samples ranged from no detection ( 〈2 cfu/100 mL) to 540 cfu/100 mL in Luoyuan Bay. Values of FCB during August to October were significantly higher than those during January to April during three year period. Monthly changes of FCB values at each year period were mainly due to monthly precipitation. In addition, compared with FCB values in difference sample sites, values of FCB in Bay-heed were significantly higher than those in middle of bay and Bay-mouth, Luoyuan Bay. However, values of FCB in Bay-mouth were significantly less than those in middle of bay. The ratios to the par of FCB in 2003, 2004, and 2005 years were 100%, 98.0%, and 97.9%, respectively. Therefore, we considered that the pollution of FCB of surface marine water in Luoyuan Bay was not serious. 展开更多
关键词 Luoyuan Bay fecal coliform bacteria horizontal distribution annual variations
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Seasonal and inter-annual variations of the primary types of the Arctic sea-ice drifting patterns 被引量:7
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作者 WANG Xiaoyu ZHAO Jinping 《Advances in Polar Science》 2012年第2期72-81,共10页
Abstract Monthly mean sea ice motion vectors and monthly mean sea level pressure (SLP) for the period of 1979-2006 are investigated to understand the spatial and temporal changes of Arctic sea-ice drift. According t... Abstract Monthly mean sea ice motion vectors and monthly mean sea level pressure (SLP) for the period of 1979-2006 are investigated to understand the spatial and temporal changes of Arctic sea-ice drift. According to the distinct differences in monthly mean ice velocity field as well as in the distribution of SLP, there are four primary types in the Arctic Ocean: Beaufort Gyre+Transpolar Drift, Anticyclonic Drift, Cyclonic Drift and Double Gyre Drift. These four types account for 81% of the total, and reveal distinct seasonal variations. The Cyclonic Drift with a large-scale anticlockwise ice motion pattern trends to prevail in summer while the Anticyclonic Drift with an opposite pattern trends to prevail in winter and spring. The prevailing seasons for the Beaufort Gyre+Transpolar Drift are spring and autumn, while the Double Gyre Drift trends to prevail in winter, especially in Feb- ruary. The annual occurring times of the Anticyclonic Drift and the Cyclonic Drift are closely correlated with the yearly mean Arc- tic Oscillation (AO) index, with a correlation coefficient of -0.54 and 0.54 (both significant with the confident level of 99%), re- spectively. When the AO index stays in a high positive (negative) condition, the sea-ice motion in the Arctic Ocean demonstrates a more anticlockwise (clockwise) drifting pattern as a whole. When the AO index stays in a neutral condition, the sea-ice motion becomes much more complicated and more transitional types trend to take place. 展开更多
关键词 sea ice ice drift drifting pattern seasonal and annual variation Arctic Oscillation
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Annual Variation of Mineral Nutrition Elements Content in Macadamia integrifolia 被引量:2
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作者 王文林 赵大宣 +6 位作者 郑树芳 覃振师 韦持章 黄锡云 谭德锦 赵静 邱文武 《Agricultural Science & Technology》 CAS 2014年第1期162-165,共4页
[Objective] To investigate the annual variation of 9 mineral nutrition ele-ments content in Macadamia integrifolia leaves. [Method] Twenty 6-year-old &quot;Guire No. 1&quot; healthy plants were selected. On the 15th... [Objective] To investigate the annual variation of 9 mineral nutrition ele-ments content in Macadamia integrifolia leaves. [Method] Twenty 6-year-old &quot;Guire No. 1&quot; healthy plants were selected. On the 15th of every month in 2011, 1 leaf in the second round from top-branch in 4 directions of the 20 trees was col ected. The content of 9 mineral elements of N, P, K, Ca, Mg, Zn, Cu, Fe and Mn were deter-mined. [Result] The results showed that the N, P, K content in leaves reached a peak in April, then N content decreased slowly, P content stayed stable, and K con-tent increased slightly; Ca, Fe content decreased in April to different degrees and then increased slowly. Mg content was consistent al year round, meanwhile Mn content decreased slightly. Cu and Zn content reached a peak in April, and then presented a rise-fal trend. [Conclusion] N, K, Ca, Mg should be supplemented in time in practice. 展开更多
关键词 Macadamia integrifolia Mineral nutrition elements annual variation
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Seasonal and annual variations of marine sinking particulate flux during 1993 ~ 1996 in the central South China Sea 被引量:1
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作者 CHEN Ronghua WIESNER M G +4 位作者 ZHENG Yulong CHENG Xinrong JIN Haiyan ZHAO Qingying ZHENG Lianfu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2007年第3期33-43,共11页
A total of 67 samples from the upper and lower sediment traps in the central South China Sea were analyzed, which were collected during 1993 ~ 1996. It is indicated that the distribution of stable isotope values, surf... A total of 67 samples from the upper and lower sediment traps in the central South China Sea were analyzed, which were collected during 1993 ~ 1996. It is indicated that the distribution of stable isotope values, surface primary productivity, fluxes of total particulate matter, carbonate, biogenic opal, organic carbon, planktonic foraminiferal species and their total amount exhibit obviously seasonal and annual fluctuations. High values of the fluxes occurred in the prevailing periods of the northeastern and southwestern monsoons, and the low values occurred during the periods between the two monsoons. The fluxes of some planktonic foraminiferal species ( Globigerinoides sacculifer , G. ruber , Globigerinita glutinata, Neogloboquadrina dutertrei ) and their percentages also exhibit two prominent peaks during the prevailing periods of the northeastern and southwestern monsoons respectively, while those of Globigerina bulloides, Globorotalia menardii and Pulleniatina obliquiloculata only exhibit one peak in the prevailing periods of the northeastern monsoon. In addition, fluxes and percentages of Globigerinoides sacculifer and Globorotalia menardii as well as the fluxes of carbonate and total amount of planktonic foraminifera decrease gradually from 1993 to 1996, and those of Globigerina bulloides, Globigerinita glutinata and biogenic opal increase gradually from 1993 to 1996. The fluxes of carbonate and organic carbon in the upper trap are higher than those in the lower one. The study indicates that the seasonal and annual variations of the sediment fluxes and planktonic foraminiferal species are mainly controlled by the changes of surface primary productivity and hydrological conditions related to the East Asian monsoon. The lower carbonate and organic carbon fluxes in the lower trap are related to the dissolution. 展开更多
关键词 FLUX MONSOON seasonal and annual variation stable isotope central South China Sea
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Estimation of annual variation of water vapor in the Arctic Ocean between 80°–87°N using shipborne GPS data based on kinematic precise point positioning 被引量:1
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作者 LUO Xiaowen ZHANG Tao +2 位作者 GAO Jinyao YANG Chunguo WU Zaocai 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第6期1-4,共4页
The measurement of atmospheric water vapor (WV) content and variability is important for meteorological and climatological research. A technique for the remote sensing of atmospheric WV content using ground-based Gl... The measurement of atmospheric water vapor (WV) content and variability is important for meteorological and climatological research. A technique for the remote sensing of atmospheric WV content using ground-based Global Positioning System (GPS) has become available, which can routinely achieve accuracies for integrated WV content of 1-2 kg/m2. Some experimental work has shown that the accuracy of WV measurements from a moving platform is comparable to that of (static) land-based receivers. Extending this technique into the marine environment on a moving platform would be greatly beneficial for many aspects of meteorological research, such as the calibration of satellite data, investigation of the air-sea interface, as well as forecasting and climatological studies. In this study, kinematic precise point positioning has been developed to investigate WV in the Arctic Ocean (80°-87°N) and annual variations are obtained for 2008 and 2012 that are identical to those related to the enhanced greenhouse effect. 展开更多
关键词 annual variation estimation water vapor Arctic Ocean kinematic precise point positioning
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Some Annual Variation Characteristics for the Northern Hemispheric Monthly Mean Precipitation Fields
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作者 汤懋苍 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1989年第2期186-201,共16页
By the utilization of monthly precipitation data from all stations in the Northern Hemisphere annexed to the 'World Survey of climatology, Vol. 1-15', the distributions of the maximum precipitation months (MPM... By the utilization of monthly precipitation data from all stations in the Northern Hemisphere annexed to the 'World Survey of climatology, Vol. 1-15', the distributions of the maximum precipitation months (MPM), the annual relative precipitation (ARP) and the monthly relative precipitation (percent of annual) in January and July are respectively mapped. Moreover the distributions of intermonthly relative precipitation variabilities from January to December are plotted as well. From these figures, the precipitation in the Northern Hemisphere may be classified into three types(continental, oceanic and transitional types) and 17 regions. The precipitation regime may also be divided into two patterns, the global and regional patterns. The global pattern consists of planetary front system and ITCZ and its inter-monthly variation shows the north-and-south shift of the rain belt; the regional pattern consists of the sea-land monsoon and plateau monsoon regime, in which the inter-monthly variation of rain belt shows a east-and-wcst shift. 展开更多
关键词 MPM Some annual variation Characteristics for the Northern Hemispheric Monthly Mean Precipitation Fields ARP
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Effects of PHC on Water Quality of Jiaozhou Bay Ⅰ. Annual Variation of PHC Content
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作者 Yang Dongfang Wang Fengyou +2 位作者 Zhu Sixi Yang Xiuqin Long Mingzhong 《Meteorological and Environmental Research》 CAS 2015年第11期31-34,共4页
Based on investigation data on PHC in Jiaozhou Bay, China from 1979 to 1983, the monthly, seasonal and annual variations of PHC content in Jiaozhou Bay were studied. The results showed that from 1979 to 1983, Jiaozhou... Based on investigation data on PHC in Jiaozhou Bay, China from 1979 to 1983, the monthly, seasonal and annual variations of PHC content in Jiaozhou Bay were studied. The results showed that from 1979 to 1983, Jiaozhou Bay was polluted by PHC seriously and then slightly in spring and summer, while Jiaozhou Bay was polluted by PHC slightly in autumn. During 1979 -1983, PHC content in the water body of Jiaozhou Bay decreased year by year, and it was close to the background value gradually. Moreover, the reduction was obvious in spring and summer but very slight in autumn. Therefore, the water quality of Jiaozhou Bay became better. 展开更多
关键词 PHC CONTENT annual variation Water quality Jiaozhou Bay China
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Annual variation rate of global sea-level rise and the prediction for the 21st century
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作者 Zheng Wenzhen Chen Zongyong +1 位作者 Wang Deyuad and Chen Kuiying ( National Maine Data and loformation Service, State oceanic Administration, Thajin 300171, China clean University of Qngdao, Qingdao 266003, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1996年第3期323-330,共8页
An analytics method of predicting the annual variation rate (AVR) of global sea-level (GSL) is developed.Through the calculation by using the mean sea-level data collected from the tidal gauge stations over the world,... An analytics method of predicting the annual variation rate (AVR) of global sea-level (GSL) is developed.Through the calculation by using the mean sea-level data collected from the tidal gauge stations over the world, a GSL rise of 0. 15~0. 16 cm/a is obtained. The predicted values of AVR of GSL for the 21st century are presented. The authors' results have been compared to those reported by other scientists at home and abroad. The method proposedhere is more convenient and precise. 展开更多
关键词 Global sea-level annual variation rate prediction for the 21st century harmonic analysis
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IMPACT OF SUMMER MONSOON'S ANNUAL VARIATION IN EAST ASIA ON DROUGHT-FLOOD DISASTERSAND WATER RESOURCES IN CHINA
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作者 Zhang Qing and Zhang Aiqun(National Climate Center,Beijing 100081) 《Natural Disaster Reduction in China》 1996年第4期156-162,共7页
This paper is based on the precipitation of a period of ten days in 336stations which are divided into seven areas of China from 1951 to 1995. We analysed drought and flood facts in the active period of summer monsoon... This paper is based on the precipitation of a period of ten days in 336stations which are divided into seven areas of China from 1951 to 1995. We analysed drought and flood facts in the active period of summer monsoon in recent 45 yearsusing Person Ⅲ Z index of drought and flood, and assessed the impact of droughtand flood 展开更多
关键词 EAST ASIA IMPACT OF SUMMER MONSOON’S annual variation IN EAST ASIA ON DROUGHT
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Discovery of the Significant Impacts of Swell Propagation on Global Wave Climate Change
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作者 ZHENG Chongwei 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期594-604,共11页
This study compared the differences in the wave climate in the South China Sea and North Indian Ocean under these two datasets:ERA-40 wave reanalysis and Mei’s hindcast wave data.In the numerical calculation of regio... This study compared the differences in the wave climate in the South China Sea and North Indian Ocean under these two datasets:ERA-40 wave reanalysis and Mei’s hindcast wave data.In the numerical calculation of regional ocean waves,the wave climate characteristics exhibited significant bias if the influence of external swells(swells from afar)was not fully considered,which may provide an incorrect basis for global climate change analysis.1)The trends of the significant wave height(SWH)obtained from the two datasets showed significant differences,such as those of the Bay of Bengal and the Java Sea in June-July-August.For the past 45 years,SWH from ERA-40(SWH-ERA)exhibited a significant annual increase in low-latitude waters of the North Indian Ocean(0.2-0.6 cm yr^(-1))and South China Sea(0.2-0.8 cm yr^(-1)).2)In the Bay of Bengal,the SWH-ERA in each month was generally 0.5 m higher than the SWH from Mei’s hindcast wave data(SWH-Mei)and can reach 1.0 m higher in some months.3)In the Bay of Bengal,SWH-ERA and SWH-Mei increased significantly at annual rates of 0.13 and 0.27 cm yr^(-1),respectively.This increasing trend was mainly reflected after 1978.SWH-ERA showed a trough in 1975(1.33 m)and a crest in 1992(1.83 m),which were not reflected in SWH-Mei. 展开更多
关键词 wave climate climatic trend monthly variation annual variation external swell
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Three-year Variations of Water, Energy and CO_2 Fluxes of Cropland and Degraded Grassland Surfaces in a Semi-arid Area of Northeastern China 被引量:16
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作者 刘辉志 涂钢 +1 位作者 符淙斌 石立庆 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第6期1009-1020,共12页
Based on 3 years (2003-05) of the eddy covariance (EC) observations on degraded grassland and cropland surfaces in a semi-arid area of Tongyu (44°25′N, 122°52′E, 184 m a.s.1.), Northeast China, seaso... Based on 3 years (2003-05) of the eddy covariance (EC) observations on degraded grassland and cropland surfaces in a semi-arid area of Tongyu (44°25′N, 122°52′E, 184 m a.s.1.), Northeast China, seasonal and annual variations of water, energy and CO2 fluxes have been investigated. The soil moisture in the thin soil layer (at 0.05, 0.10 and 0.20 m) clearly indicates the pronounced annual wet-dry cycle; the annual cycle is divided into the wet (growing season) and dry seasons (non-growing season). During the growing season (from May to September), the sensible and latent heat fluxes showed a linear dependence on the global solar radiation. However, in the non-growing season, the latent heat flux was always less than 50 W m^-2, while the available energy was dissipated as sensible, rather than latent heat flux. During the growing season in 2003-05, the daily average sensible and latent heat fluxes were larger on the cropland surface than on the degraded grassland surface. The cropland ecosystem absorbed more CO2 than the degraded grassland ecosystem in the growing season in 2003-05. The total evapotranspiration on the cropland was more than the total precipitation, while the total evapotranspiration on the degraded grassland was almost the same as the total annual precipitation in the growing season. The soil moisture had a good correlation with the rainfall in the growing season. Precipitation in the growing season is an important factor on the water and carbon budget in the semi-arid area. 展开更多
关键词 WATER energy and flux semi-arid area eddy covariance seasonal and annual variation
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Variations of electron density and temperature in ionosphere based on the DEMETER ISL data 被引量:1
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作者 Yufei He Dongmei Yang +2 位作者 Rong Zhu Jiadong Qian M Parrot 《Earthquake Science》 CSCD 2010年第4期349-355,共7页
Observations of the Langmuir Probe Instrument (ISL, Instrument Sonde de Langmuir) onboard the DEMETER satellite during four years from 2006 to 2009 were used to analyze the tempo-spatial variations of electron densi... Observations of the Langmuir Probe Instrument (ISL, Instrument Sonde de Langmuir) onboard the DEMETER satellite during four years from 2006 to 2009 were used to analyze the tempo-spatial variations of electron density (Ne) and temperature (Te) in the ionosphere. Twenty four research bins with each covering an area with 10° in longitude and 2° in latitude were selected to study the spatial distributions of Ne and Te. The results indicate that both Ne and Te have strong an- nual variations in the topside ionosphere at 660 krn altitude. The semiannual anomaly and equinoctial asymmetry which are usually well known as the features of F-layer also exist in the topside ionosphere at low- and mid-latitudes. The yearly varia- tion of No is opposite to the peak electron density of the F2-1ayer (NmF2) at higher latitudes in daytime and both are similar in nighttime. Also the yearly variations of Tc at low-latitude are contrary to that at 600 km in daytime and similar in nighttime An interesting feature of nighttime Te at low-latitude is an obvious annual variation in the northern hemisphere and semian- nual variation in the southern hemisphere. The yearly variations of Te in daytime have negative and positive correlation with Ne at mid- and high-latitudes, respectively. Both Nc and Te in the neighborhood bins at the same latitude have a high correlation. In ionospheric events analyzing, this information may help to understand the characteristics of the variation and to dis- tinguish the reliable abnormality from the normal background map. 展开更多
关键词 seasonal variation annual variation spatial distribution Ne Te DEMETER satellite
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Analysis on Apparent Resistivity Variations of Garzê Station before the 2013 Lushan M_S 7. 0 Earthquake
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作者 Xie Tao Lu Jun +1 位作者 Ren Yuexia Zhao Minyuan 《Earthquake Research in China》 2014年第3期388-402,共15页
A trend increase in apparent resistivity has been observed in the N30°E monitoring direction at Garze Seismic Station since July 2011. This increase trend in geo-electric resistivity has been observed in the N60&... A trend increase in apparent resistivity has been observed in the N30°E monitoring direction at Garze Seismic Station since July 2011. This increase trend in geo-electric resistivity has been observed in the N60°W direction since 2012. During the period of the increase, the national highway No.317 was expanded in the monitoring area, so the potential electrodes in the N30°E direction had to be moved 10m towards the current electrodes. We interpreted the electric sounding data of Garz6 Seismic Station with a horizontally layered model. Analysis based on this model showed that the shift of potential electrodes can cause a 4 l-l.m rise to the measurements in the N30°E direction. Therefore, apparent resistivity of the two directions increased in the same time in 2012 after offsetting the effects from electrodes shift. Sensitivity coefficients of the two observation directions were also obtained using the model. Sensitivity coefficients of both directions were negative for the shallow layers, which can well explain the unexpected annual variations of Garze Seismic Station. In order to quantitatively analyze the effects from the expansion of the national highway on the observation, we constructed a finite element model based on the electrical structure. Analysis results also suggested that the expansion of the national highway could only cause a 0. 15 Ω·m decrease in the N60°W monitoring direction and 0. 1 Ω· m increase in the N30°E direction. Additionally, the valley values of annual variation of 2013 were distinctively higher than that of other years since 2008, meaning that there was an abnormal rise in apparent resistivity in the two observation directions at Garz~ Seismic Station before the Lushan earthquake. However, the rise was contrary to the decline variation before the Wenchuan earthquake. Therefore, it is still unsure whether or not the rise variation is related to the Lushan earthquake. 展开更多
关键词 Lushan earthquake Garze Seismic Station Apparent resistivity Trendincrease annual variation
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Research on runoff variations based on wavelet analysis and wavelet neural network model: A case study of the Heihe River drainage basin (1944-2005) 被引量:6
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作者 WANG Jun MENG Jijun 《Journal of Geographical Sciences》 SCIE CSCD 2007年第3期327-338,共12页
The Heihe River drainage basin is one of the endangered ecological regions of China. The shortage of water resources is the bottleneck, which constrains the sustainable development of the region. Many scholars in Chin... The Heihe River drainage basin is one of the endangered ecological regions of China. The shortage of water resources is the bottleneck, which constrains the sustainable development of the region. Many scholars in China have done researches concerning this problem. Based on previous researches, this paper analyzed characteristics, tendencies, and causes of annual runoff variations in the Yingluo Gorge (1944-2005) and the Zhengyi Gorge (1954-2005), which are the boundaries of the upper reaches, the middle reaches, and the lower reaches of the Heihe River drainage basin, by wavelet analysis, wavelet neural network model, and GIS spatial analysis. The results show that: (1) annual runoff variations of the Yingluo Gorge have principal periods of 7 years and 25 years, and its increasing rate is 1.04 m^3/s.10y; (2) annual runoff variations of the Zhengyi Gorge have principal periods of 6 years and 27 years, and its decreasing rate is 2.25 m^3/s.10y; (3) prediction results show that: during 2006-2015, annual runoff variations of the Yingluo and Zhengyi gorges have ascending tendencies, and the increasing rates are respectively 2.04 m^3/s.10y and 1.61 m^3/s.10y; (4) the increase of annual runoff in the Yingluo Gorge has causal relationship with increased temperature and precipitation in the upper reaches, and the decrease of annual runoff in the Zhengyi Gorge in the past decades was mainly caused by the increased human consumption of water resources in the middle researches. The study results will provide scientific basis for making rational use and allocation schemes of water resources in the Heihe River drainage basin. 展开更多
关键词 annual runoff variations wavelet analysis wavelet neural network model GIS spatial analysis HeiheRiver drainage basin
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Trend and seasonal variations of atmospheric CH_4 in Beijing 被引量:2
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作者 WANG Yue\|si, WANG Ming\|xing, LUO Dong\|mei, ZHENG Xun\|hua, ZHOU Li (Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第3期369-374,共6页
The atmospheric CH\-4 in Beijing is still increasing, even though its increasing rate has significantly decreased from 1.76%/a during 1985—1989 to 0.50%/a during 1990—1997. The seasonal variation of CH\-4 concen... The atmospheric CH\-4 in Beijing is still increasing, even though its increasing rate has significantly decreased from 1.76%/a during 1985—1989 to 0.50%/a during 1990—1997. The seasonal variation of CH\-4 concentration showed a double\|peak pattern, one peak appearing in winter and the other in summer. It is evident that the annually seasonal variations of atmospheric CH\-4 in Beijing are different. From 1986 to 1997, the atmospheric CH\-4 increased by 185 ppbv, 37% and 21% of which were due to the increase in winter and in summer, respectively. After 1993, the annually seasonal increasing rate of CH\-4 concentration in summer (due to emission from biogenic sources) is negative while the increasing rate in winter (due to emission from non\|biogenic sources) is positive about 25 ppbv/a. As a result, the increase of CH\-4 emission from non\|biogenic sources in winter is the major reason that caused the annually seasonal increasing rate from 1993 to 1997. The biogenic sources in Beijing are shrinking while the non\|biogenic ones (such as fossil fuel combustion) are enlarging. 展开更多
关键词 atmospheric CH\-4 increasing rate seasonal variation annually seasonal variation
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Distribution of Fe, Mn and Cu Contents in Cashew Leaves
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作者 黄海杰 梁李宏 +2 位作者 王金辉 张中润 黄伟坚 《Agricultural Science & Technology》 CAS 2016年第11期2599-2601,2614,共4页
[Objective] The aim was to find out the distribution of Fe, Mn and Cu contents in cashew leaves. [Method] Using the cashew orchard with stable yield in Hainan as the objects, the sampling sites were arranged systemati... [Objective] The aim was to find out the distribution of Fe, Mn and Cu contents in cashew leaves. [Method] Using the cashew orchard with stable yield in Hainan as the objects, the sampling sites were arranged systematically, and all leaf samples were collected during the annual growth period, so as to analyze the con- tents of trace elements of Fe, Mn and Cu in cashew leaves, as well as to clarify the distribution rules of Fe, Mn and Cu contents in cashew leaves. [Result] The contents of Fe, Mn and Cu in cashew leaves were related with the annual growing period that in October, when the growth of cashew tree became active to accumu- late nutrients for the following bud differentiation and fruit growth, the contents of trace elements in the leaves increased gradually, while in March of the next year, when the fruit-setting consumed a large amount of nutrients, the contents of trace elements in the leaves decreased gradually. [Conclusion] This study provided ideas for the management of nutrients in cashew. 展开更多
关键词 CASHEW FE MN CU annual variation
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THE COMPARISON OF CHINESE AND EUROPEAN STREAM RUNOFF
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作者 Cheng Tianwen(Institute of Geography, CAS, Beijing 100101People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1994年第Z1期102-109,共8页
This paper compares stream stream runoff in China in terms of drainage basin, water balance, and regional distribution and regime of stream runoff with that in Europe. European stream runoff resources are more abun... This paper compares stream stream runoff in China in terms of drainage basin, water balance, and regional distribution and regime of stream runoff with that in Europe. European stream runoff resources are more abundant than that of China. Europe has 28 rivers with runoff volume exceeding 10 km3, and China only has 19.But Europe has no rivers like those in China which are long andhave abundant waer volume such as Changiiang (Yangtze River) and Zhujiang. Heat conditions of the European water-abundant and water-sufficient zones are poor and their agiculture are not flourishing.In China these zones have very good heat conditions and are main farm production regions. The interannual and annual variation of stream runoff are the sane to the irrespective feedings in Europe and China. 展开更多
关键词 stream runoff drainage basin water balance distribution interannual variation annual variation
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Relation of ice conditions to climate change in the Bohai Sea of China 被引量:7
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作者 Bai Shan, Liu Qinzheng, Wu Huiding I. National Center fOr Marine Environmnt FOrecats, ffeijing l(XX)8I. China. 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2001年第3期331-342,共12页
The ice conditions in the Bohai Sea and the northern Huanghai Sea greatly change from year to year with winter climate. Ice only covers below 15% of the the waters during the wannest win-ter, while it covers more than... The ice conditions in the Bohai Sea and the northern Huanghai Sea greatly change from year to year with winter climate. Ice only covers below 15% of the the waters during the wannest win-ter, while it covers more than 80% during the coldest winter. Ice observation and data acquisition are outlined in the paper. The ice-covered area, the position of ice edge and the ice grades give indication of the ice conditions. The local climate of the waters can be expressed by using the air temperature of the stations of Dalian and Yingkou. The variation of the ice condition indexes with the monthly mean air temperature at Dalian from 1952 to 2000 is shown, as well. The local climate and ice conditions in the waters are affected by many factors,such as, evolution of the general atmospheric circulation and the solar activity. The delayed correlation between the ice conditions and lots of the affecting factors is analysed in the paper. The ice conditions are continuously mild since the 1990s, that is relative to the tendency of the global warming. The ice condition variation of the Bohai Sea is related to the El Nino event and the sunspot period. The seasonal evolution of the ice conditions is also described in the paper. 展开更多
关键词 Sea ice annual variation seasonal evolution climatic factor the Bohai Sea
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Formation cause of thermal infrared high temperature belt along Honghe fault and its relation to earthquakes
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作者 屈春燕 单新建 马瑾 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2006年第1期93-99,共7页
Aiming at two Dayao earthquakes with magnitude more than 6 occurred in 2003 in Yunnan Province, we analyzed and interpreted the NOAA satellite thermal infrared images of 1999, 2003 and 2004 in Chuandian region, and al... Aiming at two Dayao earthquakes with magnitude more than 6 occurred in 2003 in Yunnan Province, we analyzed and interpreted the NOAA satellite thermal infrared images of 1999, 2003 and 2004 in Chuandian region, and also calculated the annual variation of brightness temperature of the hot belt along Honghe fault to explore the formation cause of the high temperature belt and its relation to the earthquakes. The results show that the high temperature belt along Honghe fault is caused by geographic environment factors, such as water system and terrain. But the annual average brightness temperature of the belt in earthquake year of 2003 is clearly higher than that in no earthquake years of 1999 and 2004, this maybe indicates that the thermal activities of Honghe fault increase in earthquake years, and can cause the annual variation anomaly of brightness temperature. We can detect and monitor this thermal activities of Honghe fault before earthquake by analyzing and comparing the relative changes of thermal infrared brightness temperature of the hot belt in different years. 展开更多
关键词 thermal infrared remote sensing annual variation anomaly earthquake precursor fault activity
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