Sesame is an important oilseed crop in Africa and Asia, owing to its high nutritional quality seed and market value. Variation in sesame seed components including oil, oleic acid,linoleic acid, and protein was investi...Sesame is an important oilseed crop in Africa and Asia, owing to its high nutritional quality seed and market value. Variation in sesame seed components including oil, oleic acid,linoleic acid, and protein was investigated by near-infrared reflectance spectrometry in 139 samples collected from different countries. Oil and protein contents were between 40.8%and 60.3%(mean 53.0%) and 15.5% to 25.5%(mean 20.4%), respectively. Linoleic acid,ranging from 31.8% to 52.4%(mean 46%) was more abundant than oleic acid(31.8%–50.6%,mean 38.1%). Light-seeded samples displayed higher nutritional quality, as they were richer in oil, protein, and linoleic acid than dark seeds. Samples from Africa had higher oil and linoleic acid contents, while Asian samples had higher oleic content. The analysis revealed West African sesame cultivars containing especially high levels of seed components, which may command high market values. Two clusters of sesame samples grouped by seed composition were obtained, including one cluster with high oil and oleic acid content and the other with high protein and linoleic acid content. This study revealed that sesame samples from Africa and Asia harbor high variation for major seed components and also provided background information for breeding high-nutrition varieties according to the demands of sesame seed markets.展开更多
Many attentions have been previously focused to identify the multiple biochemical components related to tea quality and health benefits,however, the natural variation of biochemical components present in tea germplasm...Many attentions have been previously focused to identify the multiple biochemical components related to tea quality and health benefits,however, the natural variation of biochemical components present in tea germplasm has not been adequately evaluated. In this study, the main biochemical components, leaf morphological and yield characteristics were evaluated for four rounds of tea leaves in a panel of 87 elite tea cultivars suitable for black, green, or oolong tea. Significant variations were observed among the tea cultivars, as well as seasonal differences in the levels of the free amino acid(FAA), caffeine(CAF), tea polyphenols(TP), water extract(WE) and TP to FAA ratio(TP/FAA). Results showed that the average levels of FAA showed a seasonal change, with the highest level of 4.0% in the 1st spring tea in the cultivars suitable for green tea and the lowest of 3.2% in summer tea in the cultivars suitable for black tea. The average CAF content was highest 3.2% in the cultivars suitable for oolong tea in the 1st spring and the lowest 2.5% in the cultivars suitable for green tea in summer. Limited seasonal and varietal variations were noticed in the average levels of WE among the three categories of tea. In addition, significant natural variation of the morphological characteristics, bud length varying from 2.5 cm to 8.7 cm, bud density from 190.3 buds · m-2to 1 730.3 buds · m-2, mature leaves biomass from 128.4 kg · hm-2to 2 888.4 kg · hm-2, and yield component traits of 100 buds(one bud with two leaves) dry weight from 3.7 g to37.7 g, tea yield/round from 444.6 kg · hm-2to 905.3 kg · hm-2, were observed. The aim of our evaluation was not only to identify the advantages of seasonal and clonal variations but also to provide a new viewpoint for their further application. Representative accessions were selected from the germplasm to promote the establishment of an inherent biochemical constituent expressing the quality of black, green, and oolong tea. The findings might be utilized to establish early selection criteria to enhance the tea breeding and production program.展开更多
Significant anomalies were observed at the geomagnetic stations in the southwest region of China before the Yingjiang M_S6. 1 earthquake and the Ludian M_S6. 5 earthquake in 2014.We processed the geomagnetic vertical ...Significant anomalies were observed at the geomagnetic stations in the southwest region of China before the Yingjiang M_S6. 1 earthquake and the Ludian M_S6. 5 earthquake in 2014.We processed the geomagnetic vertical component diurnal variation data by the spatial correlation method. The results show that during the period from April 1 to May 20,2014,there existed quasi-synchronous decrease changes in the coefficient curves between the five geomagnetic stations of Guiyang,Hechi,Nanshan,Muli,Yongning and Xinyi and Hongshan stations. Furthermore,there was a high gradient zone in the normalized correlation coefficient contour map with background values removed. The epicenters of the Yingjiang M_S6. 1 earthquake and the Ludian M_S6. 5 earthquake are located in the gradient zone or near the gradient zone.展开更多
Progeny testing of oil palm interspecific hybrids was conducted in four trials in Kluang, Ulu Paka, Teluk Intan and Carey Island, Malaysia. The interspecific hybrids (O × P) were created according to the North ...Progeny testing of oil palm interspecific hybrids was conducted in four trials in Kluang, Ulu Paka, Teluk Intan and Carey Island, Malaysia. The interspecific hybrids (O × P) were created according to the North Carolina Model I (NCM I) mating design, using Elaeis oleifera (0) and Elaeis guineensis var. pisifera (P) as the maternal and paternal parents, respectively. Differences among O, P and O-within-P were determined by the performance (bunch yield, components and vegetative traits) of the progenies. There were significant differences among P for fresh fruit bunch (FFB) yield, bunch number (BN) and average bunch weight (ABW) in Kluang, Ulu Paka and Teluk Intan, but not in Carey Island. FFB yield was generally higher on coastal soils (Teluk Intan and Carey Island) than inland soils (Kluang and Ulu Paka). Heritability was calculated based on the intraclass correlation. Heritability estimates for these three yield components were variable, depending on the breeding material and environment in which the materials were tested. Fruit to bunch (F/B) and oil to bunch (O/B) of parthenocarpic fruits were important in determining the overall O/B of the interspecific hybrids. The O x P hybrids in Kluang showed the lowest height increment with only a mean of 14.0 cm/year, whereas in Ulu Paka and Teluk Intan, the values were higher at 24.0 cm/year and 25.0 cm/year, respectively. The study showed that the FFB yields ofoil palm interspecific hybrids performed better in coastal soils than inland soils.展开更多
In this paper, we use the daily ranges of the vertical magnetic intensity of approximately 76 geomagnetic stations from January 1, 2008 to December 31, 2010 to analyze the spatial and temporal characteristics of Z ran...In this paper, we use the daily ranges of the vertical magnetic intensity of approximately 76 geomagnetic stations from January 1, 2008 to December 31, 2010 to analyze the spatial and temporal characteristics of Z ranges. The results are summarized as follows: (1) Temporally, we use regressive analysis and FFT analysis to analyze the data. The results show that the Z component daily ranges of all stations have an obvious cyclical variation, the computed Fourier spectra of all data sets have clearly resolved the required periodicities in the data, in the form of distinct peaks at days 365, 183, 22, and 73, and the power spectra of day 365 is the highest in all periods. (2) In terms of spatial variation, the daily ranges show nonlinear variation with latitude in China. The results show the existence of a point of inflexion (maximal value point) nearby at about 25°N, the daily ranges of Z rise from 15°~25°N and have a good linear decrease variation along with 25°~50°N. (3) Compared with the spatial and temporal variations of Z daily ranges with the Sq current inversion, we found that the spatial and temporal characteristics of Z ranges are decided mainly by the spatio-temporal evolution of the Sq current system. (4) If the latitudes of the maximum amplitudes of variation of the vertical component in the geomagnetic quiet days are roughly taken as the latitudes corresponding to the foci of Sq overhead current system, we can see that these latitudes of foci become higher in summer, are lowest in winter and highest during Equinoxes, displaying conspicuous monthly and daily variations. For two successive geomagnetic quiet days, the latitudes of foci may vary ten degrees.展开更多
Phoebe bournei(Hemsl.) Yang is a rare and protected plant in China. This study was conducted to determine the phenotypic variation in this species and to document phenotypic variation within and among populations of...Phoebe bournei(Hemsl.) Yang is a rare and protected plant in China. This study was conducted to determine the phenotypic variation in this species and to document phenotypic variation within and among populations of P. bournei. Nested analysis of variance, coefficient of variation, multiple comparisons, principal component analysis(PCA) and correlation analysis were used to analyze ten phenotypic traits in ten natural populations of P.bournei from both the northeastern and the primary region of the range of this species. Significant differences among and within populations were observed in leaf and seed phenotypic traits. Variation among populations(34.92%)was greater than that within populations(26.19%). The mean phenotypic differentiation coefficient was 53.77% among populations, indicating that variation among populations comprised the majority of the phenotypic variation of P. bournei. The coefficient of variance(CV) of ten traits varied from 6.44 to 18.45%, with an average of 12.03%.The CV of leaf traits among populations(15.64%) was higher than that of seed traits(8.60%), indicating that seed traits were more stable. The results from CV and PCA indicated that leaf area, leaf length and thousand seed weight were the main factors accounting for the observed phenotypic variations. Significant or highly significant correlations were observed among most leaf and/or in seed phenotypic traits, whereas no significant correlations were observed between phenotypic traits and geographic factors.Based on cluster analysis, the ten populations can be divided into three clusters. These clusters were not a result of geographic distances.展开更多
Dynamic variation of water quality in Meiliang Bay and part of West Taihu Lake has been analysed based on data from 1991 to 1992. Principal Component Analysis is used to reveal the mutual relationships of various fact...Dynamic variation of water quality in Meiliang Bay and part of West Taihu Lake has been analysed based on data from 1991 to 1992. Principal Component Analysis is used to reveal the mutual relationships of various factors. It is shown that there existis an obvious spatial and temporal variation in the main factors of water quality. Annual values of TP, CON, TN, Chl-a and conductivity decrease evidently from inner Meiliang Bay to the outer from north to south. TP and TN fluctuate seasonally with much higher value in winter. This is particularly true for the mouth of Liangxi River. In addition, the Chl-1 has a synchronous variation with water temperature, although being lagged a little, and closely relates to TP and TN. Finally, the results from Principal Component Analysis show that TP, TN, SS (or SD), water temperature and Chl-a are the most influential factors to water qualuty in this area, and both suspensions and algae can contribute to transparency to Taihu Lake.展开更多
Chemometric approach based on principal component analysis(PCA) was utilized to examine the spatial variances of environmental and ecological characteristics in the Zhujiang River(Pearl River) Estuary and adjacent...Chemometric approach based on principal component analysis(PCA) was utilized to examine the spatial variances of environmental and ecological characteristics in the Zhujiang River(Pearl River) Estuary and adjacent waters(ZREAW) in the South China Sea. The PCA result shows that the ZREAW can be divided into different zones according to the principal components and geographical locations of the study stations,and indicates that there are distinct regional variances on environmental features and the corresponding phytoplankton biomass and community structures among different areas. The spatial distribution of ecological features was implied to be influenced by various degrees of the different water resources,such as the Pearl River discharges,the coastal current and the oceanic water from the South China Sea. The variation of the biomass maximum zone and the complex impacts on the spatial distributions of phytoplankton biomass and production were also evaluated.展开更多
In this study, a regional air quality model system (RAQMS) was applied to investigate the spatial distributions and seasonal variations of atmospheric aerosols in 2006 over East Asia. Model validations demonstrated ...In this study, a regional air quality model system (RAQMS) was applied to investigate the spatial distributions and seasonal variations of atmospheric aerosols in 2006 over East Asia. Model validations demonstrated that RAQMS was able to reproduce the evolution processes of aerosol components reasonably well. Ground-level PM10 (particles with aerodynamic diameter ≤10 μm) concentrations were highest in spring and lowest in summer and were characterized by three maximum centers: the Taklimakan Desert (-1000 μg m^-3), the Gobi Desert (-400 μg m^-3), and the Huabei Plain (- 300 μg m^-3) of China. Vertically, high PM10 concentrations ranging from 100 μg m-3 to 250 μg m-3 occurred from the surface to an altitude of 6000 m at 30°-45°N in spring. In winter, the vertical gradient was so large that most aerosols were restricted in the boundary layer. Both sulfate and ammonium reached their highest concentrations in autumn, while nitrate reached its maximum level in winter. Black carbon and organic carbon aerosol concentrations reached maximums in winter. Soil dust were strongest in spring, whereas sea salt exerted the strongest influence on the coastal regions of eastern China in summer. The estimated burden of anthropogenic aerosols was largest in winter (1621 Gg) and smallest in summer (1040 Gg). The sulfate burden accounted for -42% of the total anthropogenic aerosol burden. The dust burden was about twice the anthropogenic aerosol burden, implying the potentially important impacts of the natural aerosols on air quality and climate over East Asia.展开更多
Asian monsoon have multiple forms of variations such as seasonal variation, intra-seasonal variation, interannual variation, etc. The interannual variations have not only yearly variations but also variations among se...Asian monsoon have multiple forms of variations such as seasonal variation, intra-seasonal variation, interannual variation, etc. The interannual variations have not only yearly variations but also variations among several years. In general, the yearly variations are described with winter temperature and summer precipitation, and the variations among several years are reflected by circulation of ENSO events. In this study, at first, we analyze the relationship between land cover and interannual monsoon variations represented by precipitation changes using Singular Value Decomposition method based on the time series precipitation data and 8km NOAA AVHRR NDVI data covering 1982 to 1993 in east Asia. Furthermore, after confirmation and reclassification of ENSO events which are recognized as the strong signal of several year monsoon variation, using the same time series NDVI data during 1982 to 1993 in east Asia, we make a Principle Component Analysis and analyzed the correlation of the 7th component eigenvectors and Southern Oscillation Index (SOI) that indicates the characteristic of ENSO events, and summed up the temporal-spatial distribution features of east Asian land cover’s inter-annual variations that are being driven by changes of ENSO events.展开更多
This study aims to explore the interdecadal variation of South Asian High(SAH) and its relationship with SST(sea surface temperature) of the tropical and subtropical regions by using the NCEP/NCAR monthly reanalysis d...This study aims to explore the interdecadal variation of South Asian High(SAH) and its relationship with SST(sea surface temperature) of the tropical and subtropical regions by using the NCEP/NCAR monthly reanalysis data from 1948 to 2012, based on the NCAR CAM 3.0 general circulation model. The results show that: 1) the intensity of SAH represents a remarkable interdecadal variation characteristic, the intensity of SAH experienced from weak to strong at the late 1970 s, and after the late 1970 s, its strength is enhanced and the area is expanded in the east-west direction.The expansion degree is greater westward than eastward, while it is opposite in summer. 2) Corresponding to the interdecadal variation of SAH intensity, after the late 1970 s, the divergent component of wind field has two ascending and three descending areas. Of the two ascending areas, one is located in the East Pacific, the other location varies with the season from the Indian Ocean in winter to the South China Sea and West Pacific in summer. Three descending areas are located in the north-central Africa, the East Asia and the Middle Pacific region respectively. 3) Corresponding to the interdecadal variation of SAH intensity, the rotational component of wind field at the lower level is an anomalous cyclone over the South China Sea and West Pacific in summer, while in winter, it is an anomalous cyclone over the Indian Ocean, and an anomalous anticyclone over the equatorial Middle Pacific. 4) Numerical simulations show that the interdecadal variation of SAH is closely related to the SST of the tropical and subtropical regions. The SST of Indian Ocean plays an important role in winter, while in summer, the SST of the South China Sea and West Pacific plays an important role, and the SST of the East Pacific also plays a certain role.展开更多
The wavenumber spectral components WN4 at the mesosphere and low thermosphere(MLT)altitudes(70–10 km)and in the latitude range between±45°are obtained from temperature data(T)observed by the Sounding of the...The wavenumber spectral components WN4 at the mesosphere and low thermosphere(MLT)altitudes(70–10 km)and in the latitude range between±45°are obtained from temperature data(T)observed by the Sounding of the Atmosphere using Broadband Emission Radiometry(SABER)instruments on board the National Aeronautics and Space Administration(NASA)’s Thermosphere–Ionosphere–Mesosphere Energetics and Dynamics(TIMED)spacecraft during the 11-year solar period from 2002 to 2012.We analyze in detail these spectral components WNk and obtain the main properties of their vertical profiles and global structures.We report that all of the wavenumber spectral components WNk occur mainly around 100 km altitude,and that the most prominent component is the wavenumber spectral component WN4 structure.Comparing these long duration temperature data with results of previous investigations,we have found that the yearly variation of spectral component WN4 is similar to that of the eastward propagating non-migrating diurnal tide with zonal wavenumber 3(DE3)at the low latitudes,and to that of the semi-diurnal tide with zonal wavenumber 2(SE2)at the mid-latitudes:the amplitudes of the A4 are larger during boreal summer and autumn at the low-latitudes;at the mid-latitudes the amplitudes have a weak peak in March.In addition,the amplitudes of component WN4 undergo a remarkable short period variation:significant day-to-day variation of the spectral amplitudes A4 occurs primarily in July and September at the low-latitudes.In summary,we conclude that the non-migrating tides DE3 and SE2 are likely to be the origins,at the low-latitudes and the mid-latitudes in the MLT region,respectively,of the observed wavenumber spectral component WN4.展开更多
Water quality of Litani River was deteriorated due to rapid population growth and industrial and agricultural activity. Multivariate analysis of spatio-temporal variation of water quality is useful to improve the proj...Water quality of Litani River was deteriorated due to rapid population growth and industrial and agricultural activity. Multivariate analysis of spatio-temporal variation of water quality is useful to improve the projects of water quality management and treatment of the river. In this work, analysis of samples from different locations at different seasons was investigated. The spatio-temporal variation of physico-chemical parameters of the water was determined. A total of 11 water quality parameters were monitored over 12 months during 2018 at 3 sites located in different areas of the river. Multivariate statistical techniques were used to study the spatio-temporal evolution of the studied parameters and the correlation between the different factors. Principal Component Analysis (PCA) was applied to the responsible factors for water quality variations during wet and dry periods. The multivariate analysis of variance (MANOVA) was also applied to the same factors and gives the best results for both spatial and temporal analysis. A black point of agricultural, industrial and sewage water pollution was identified in Jeb-Jennine station from the high concentrations of ammonia, sulfate and phosphate. This difference was proved by the major changes in the values of the parameters from one station to the other. Jeb-Jennine represents a main pollution area in the river. The high ammonia, sulfate and phosphate concentrations result from the important agricultural, industrial and sewage water pollution in the area. A high bacterial activity was highlighted in Jeb-Jennine and Quaroun stations because of the presence of the high nitrite concentrations in the two locations. All parameters are highly affected by climate factors, especially temperature and precipitation. TDS, salinity, electrical conductivity and the concentrations of all pollutants increase during wet season affected by the runoff. Other factors can affect the water quality of the river for example geographical features of the region and seasonal human activity like tourism. The correlation between different parameters was evaluated using PCA statistical method. This correlation is not stable, and evolves between wet and dry season.展开更多
We present two kinds of exact vector-soliton solutions for coupled nonlinear Schrodinger equations with time- varying interactions and time-varying harmonic potential. Using the variational approach, we investigate th...We present two kinds of exact vector-soliton solutions for coupled nonlinear Schrodinger equations with time- varying interactions and time-varying harmonic potential. Using the variational approach, we investigate the dynamics of the vector solitons. It is found that the two bright sol/tons oscillate about slightly and pass through each other around the equilibration state which means that they are stable under our modeh At the same time, we obtain the opposite situation for dark-dark solitons.展开更多
基金financially supported by the National Key Technology R&D Program of China (during the 12th Five-Year Plan Period) (2013BAD01B03-08)Agricultural Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences (CAAS-ASTIP-2013-OCRI)+3 种基金the African-German Network of Excellence in Science (AGNES) for granting a Mobility Grant in 2016sponsored by German Federal Ministry of Education and Researchsupported by the Alexander von Humboldt Foundationthe Chinese Scholarship Council (2015GXY934) for a fellowship
文摘Sesame is an important oilseed crop in Africa and Asia, owing to its high nutritional quality seed and market value. Variation in sesame seed components including oil, oleic acid,linoleic acid, and protein was investigated by near-infrared reflectance spectrometry in 139 samples collected from different countries. Oil and protein contents were between 40.8%and 60.3%(mean 53.0%) and 15.5% to 25.5%(mean 20.4%), respectively. Linoleic acid,ranging from 31.8% to 52.4%(mean 46%) was more abundant than oleic acid(31.8%–50.6%,mean 38.1%). Light-seeded samples displayed higher nutritional quality, as they were richer in oil, protein, and linoleic acid than dark seeds. Samples from Africa had higher oil and linoleic acid contents, while Asian samples had higher oleic content. The analysis revealed West African sesame cultivars containing especially high levels of seed components, which may command high market values. Two clusters of sesame samples grouped by seed composition were obtained, including one cluster with high oil and oleic acid content and the other with high protein and linoleic acid content. This study revealed that sesame samples from Africa and Asia harbor high variation for major seed components and also provided background information for breeding high-nutrition varieties according to the demands of sesame seed markets.
基金jointly supported by the National Key Research and Development Program of China (Grant No. 2021YFD1000401)the National Natural Science Foundation of China (Grant No.32070376)+1 种基金the Program of Horticultural Crop Germplasm Resources in Hubei Province (Grant No. 2021DFE016)the Key Technology of Safety Production to Improve Tea Quality and Efficiency in Three Gorges Reservoir Area。
文摘Many attentions have been previously focused to identify the multiple biochemical components related to tea quality and health benefits,however, the natural variation of biochemical components present in tea germplasm has not been adequately evaluated. In this study, the main biochemical components, leaf morphological and yield characteristics were evaluated for four rounds of tea leaves in a panel of 87 elite tea cultivars suitable for black, green, or oolong tea. Significant variations were observed among the tea cultivars, as well as seasonal differences in the levels of the free amino acid(FAA), caffeine(CAF), tea polyphenols(TP), water extract(WE) and TP to FAA ratio(TP/FAA). Results showed that the average levels of FAA showed a seasonal change, with the highest level of 4.0% in the 1st spring tea in the cultivars suitable for green tea and the lowest of 3.2% in summer tea in the cultivars suitable for black tea. The average CAF content was highest 3.2% in the cultivars suitable for oolong tea in the 1st spring and the lowest 2.5% in the cultivars suitable for green tea in summer. Limited seasonal and varietal variations were noticed in the average levels of WE among the three categories of tea. In addition, significant natural variation of the morphological characteristics, bud length varying from 2.5 cm to 8.7 cm, bud density from 190.3 buds · m-2to 1 730.3 buds · m-2, mature leaves biomass from 128.4 kg · hm-2to 2 888.4 kg · hm-2, and yield component traits of 100 buds(one bud with two leaves) dry weight from 3.7 g to37.7 g, tea yield/round from 444.6 kg · hm-2to 905.3 kg · hm-2, were observed. The aim of our evaluation was not only to identify the advantages of seasonal and clonal variations but also to provide a new viewpoint for their further application. Representative accessions were selected from the germplasm to promote the establishment of an inherent biochemical constituent expressing the quality of black, green, and oolong tea. The findings might be utilized to establish early selection criteria to enhance the tea breeding and production program.
基金sponsored by the Spark Program for Earthquake Science and Technology,China Earthquake Administration(Serial No.XH17010Y)the Seismic Tracking and Orientation Task,China Earthquake Administration(Serial No.2018010401)Major Scientific and Technical Project of Science and Technology Department of Inner Mongolia in 2016(Strong Earthquake Track in the Short Stage and Integration Innovation of Stereoscopic Observation Technology in Space and Ground)
文摘Significant anomalies were observed at the geomagnetic stations in the southwest region of China before the Yingjiang M_S6. 1 earthquake and the Ludian M_S6. 5 earthquake in 2014.We processed the geomagnetic vertical component diurnal variation data by the spatial correlation method. The results show that during the period from April 1 to May 20,2014,there existed quasi-synchronous decrease changes in the coefficient curves between the five geomagnetic stations of Guiyang,Hechi,Nanshan,Muli,Yongning and Xinyi and Hongshan stations. Furthermore,there was a high gradient zone in the normalized correlation coefficient contour map with background values removed. The epicenters of the Yingjiang M_S6. 1 earthquake and the Ludian M_S6. 5 earthquake are located in the gradient zone or near the gradient zone.
文摘Progeny testing of oil palm interspecific hybrids was conducted in four trials in Kluang, Ulu Paka, Teluk Intan and Carey Island, Malaysia. The interspecific hybrids (O × P) were created according to the North Carolina Model I (NCM I) mating design, using Elaeis oleifera (0) and Elaeis guineensis var. pisifera (P) as the maternal and paternal parents, respectively. Differences among O, P and O-within-P were determined by the performance (bunch yield, components and vegetative traits) of the progenies. There were significant differences among P for fresh fruit bunch (FFB) yield, bunch number (BN) and average bunch weight (ABW) in Kluang, Ulu Paka and Teluk Intan, but not in Carey Island. FFB yield was generally higher on coastal soils (Teluk Intan and Carey Island) than inland soils (Kluang and Ulu Paka). Heritability was calculated based on the intraclass correlation. Heritability estimates for these three yield components were variable, depending on the breeding material and environment in which the materials were tested. Fruit to bunch (F/B) and oil to bunch (O/B) of parthenocarpic fruits were important in determining the overall O/B of the interspecific hybrids. The O x P hybrids in Kluang showed the lowest height increment with only a mean of 14.0 cm/year, whereas in Ulu Paka and Teluk Intan, the values were higher at 24.0 cm/year and 25.0 cm/year, respectively. The study showed that the FFB yields ofoil palm interspecific hybrids performed better in coastal soils than inland soils.
基金supported by the special fundamental research fund of Institute of Geophysics,CEA for Central Public Welfare Research Institutes(DQJB11C10)the fund for the Task of Tracing Earthquake Trend of China Earthquake Administration(Grant No.2010020705)
文摘In this paper, we use the daily ranges of the vertical magnetic intensity of approximately 76 geomagnetic stations from January 1, 2008 to December 31, 2010 to analyze the spatial and temporal characteristics of Z ranges. The results are summarized as follows: (1) Temporally, we use regressive analysis and FFT analysis to analyze the data. The results show that the Z component daily ranges of all stations have an obvious cyclical variation, the computed Fourier spectra of all data sets have clearly resolved the required periodicities in the data, in the form of distinct peaks at days 365, 183, 22, and 73, and the power spectra of day 365 is the highest in all periods. (2) In terms of spatial variation, the daily ranges show nonlinear variation with latitude in China. The results show the existence of a point of inflexion (maximal value point) nearby at about 25°N, the daily ranges of Z rise from 15°~25°N and have a good linear decrease variation along with 25°~50°N. (3) Compared with the spatial and temporal variations of Z daily ranges with the Sq current inversion, we found that the spatial and temporal characteristics of Z ranges are decided mainly by the spatio-temporal evolution of the Sq current system. (4) If the latitudes of the maximum amplitudes of variation of the vertical component in the geomagnetic quiet days are roughly taken as the latitudes corresponding to the foci of Sq overhead current system, we can see that these latitudes of foci become higher in summer, are lowest in winter and highest during Equinoxes, displaying conspicuous monthly and daily variations. For two successive geomagnetic quiet days, the latitudes of foci may vary ten degrees.
基金financially supported by the Major Science and Technology Project(No.2010C12009)Agricultural New Varieties Breeding Project(No.2012C12908-4)Key Research and Development Plan(No.2017C02028)of Zhejiang Province,China
文摘Phoebe bournei(Hemsl.) Yang is a rare and protected plant in China. This study was conducted to determine the phenotypic variation in this species and to document phenotypic variation within and among populations of P. bournei. Nested analysis of variance, coefficient of variation, multiple comparisons, principal component analysis(PCA) and correlation analysis were used to analyze ten phenotypic traits in ten natural populations of P.bournei from both the northeastern and the primary region of the range of this species. Significant differences among and within populations were observed in leaf and seed phenotypic traits. Variation among populations(34.92%)was greater than that within populations(26.19%). The mean phenotypic differentiation coefficient was 53.77% among populations, indicating that variation among populations comprised the majority of the phenotypic variation of P. bournei. The coefficient of variance(CV) of ten traits varied from 6.44 to 18.45%, with an average of 12.03%.The CV of leaf traits among populations(15.64%) was higher than that of seed traits(8.60%), indicating that seed traits were more stable. The results from CV and PCA indicated that leaf area, leaf length and thousand seed weight were the main factors accounting for the observed phenotypic variations. Significant or highly significant correlations were observed among most leaf and/or in seed phenotypic traits, whereas no significant correlations were observed between phenotypic traits and geographic factors.Based on cluster analysis, the ten populations can be divided into three clusters. These clusters were not a result of geographic distances.
文摘Dynamic variation of water quality in Meiliang Bay and part of West Taihu Lake has been analysed based on data from 1991 to 1992. Principal Component Analysis is used to reveal the mutual relationships of various factors. It is shown that there existis an obvious spatial and temporal variation in the main factors of water quality. Annual values of TP, CON, TN, Chl-a and conductivity decrease evidently from inner Meiliang Bay to the outer from north to south. TP and TN fluctuate seasonally with much higher value in winter. This is particularly true for the mouth of Liangxi River. In addition, the Chl-1 has a synchronous variation with water temperature, although being lagged a little, and closely relates to TP and TN. Finally, the results from Principal Component Analysis show that TP, TN, SS (or SD), water temperature and Chl-a are the most influential factors to water qualuty in this area, and both suspensions and algae can contribute to transparency to Taihu Lake.
基金The Knowledge Innovation Project of Chinese Academy of Sciences under contract Nos KZCX2-YW-Q07, KZCX2-YW-T001, KZCX2-YW-213 and SQ200805the National Natural Science Foundation of China under contract Nos U0633007, 40906057 and 40531006
文摘Chemometric approach based on principal component analysis(PCA) was utilized to examine the spatial variances of environmental and ecological characteristics in the Zhujiang River(Pearl River) Estuary and adjacent waters(ZREAW) in the South China Sea. The PCA result shows that the ZREAW can be divided into different zones according to the principal components and geographical locations of the study stations,and indicates that there are distinct regional variances on environmental features and the corresponding phytoplankton biomass and community structures among different areas. The spatial distribution of ecological features was implied to be influenced by various degrees of the different water resources,such as the Pearl River discharges,the coastal current and the oceanic water from the South China Sea. The variation of the biomass maximum zone and the complex impacts on the spatial distributions of phytoplankton biomass and production were also evaluated.
基金supported by the Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No. KZCX2-YW-Q11-03)the "Strategic Priority Research Program" of the Chinese Academy of Sciences (Grant No. XDA05100502)+2 种基金the National 973 Project of China (Grant No. 2010CB950804)the National Natural Science Foundation of China (GrantNo. 41075106)the Hundred Talents Program of the Chinese Academy of Sciences
文摘In this study, a regional air quality model system (RAQMS) was applied to investigate the spatial distributions and seasonal variations of atmospheric aerosols in 2006 over East Asia. Model validations demonstrated that RAQMS was able to reproduce the evolution processes of aerosol components reasonably well. Ground-level PM10 (particles with aerodynamic diameter ≤10 μm) concentrations were highest in spring and lowest in summer and were characterized by three maximum centers: the Taklimakan Desert (-1000 μg m^-3), the Gobi Desert (-400 μg m^-3), and the Huabei Plain (- 300 μg m^-3) of China. Vertically, high PM10 concentrations ranging from 100 μg m-3 to 250 μg m-3 occurred from the surface to an altitude of 6000 m at 30°-45°N in spring. In winter, the vertical gradient was so large that most aerosols were restricted in the boundary layer. Both sulfate and ammonium reached their highest concentrations in autumn, while nitrate reached its maximum level in winter. Black carbon and organic carbon aerosol concentrations reached maximums in winter. Soil dust were strongest in spring, whereas sea salt exerted the strongest influence on the coastal regions of eastern China in summer. The estimated burden of anthropogenic aerosols was largest in winter (1621 Gg) and smallest in summer (1040 Gg). The sulfate burden accounted for -42% of the total anthropogenic aerosol burden. The dust burden was about twice the anthropogenic aerosol burden, implying the potentially important impacts of the natural aerosols on air quality and climate over East Asia.
基金Knowledge Innovation Project of CAS, No.KZCX2-308Natural Science Foundation of Inner Mongolia Autonomous Region, No. 20010905-14
文摘Asian monsoon have multiple forms of variations such as seasonal variation, intra-seasonal variation, interannual variation, etc. The interannual variations have not only yearly variations but also variations among several years. In general, the yearly variations are described with winter temperature and summer precipitation, and the variations among several years are reflected by circulation of ENSO events. In this study, at first, we analyze the relationship between land cover and interannual monsoon variations represented by precipitation changes using Singular Value Decomposition method based on the time series precipitation data and 8km NOAA AVHRR NDVI data covering 1982 to 1993 in east Asia. Furthermore, after confirmation and reclassification of ENSO events which are recognized as the strong signal of several year monsoon variation, using the same time series NDVI data during 1982 to 1993 in east Asia, we make a Principle Component Analysis and analyzed the correlation of the 7th component eigenvectors and Southern Oscillation Index (SOI) that indicates the characteristic of ENSO events, and summed up the temporal-spatial distribution features of east Asian land cover’s inter-annual variations that are being driven by changes of ENSO events.
基金National Natural Science Foundation for Yong Scholars(41105059,41305079)General Program of the National Natural Science Foundation of China(41575070,41230422,41575102)Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘This study aims to explore the interdecadal variation of South Asian High(SAH) and its relationship with SST(sea surface temperature) of the tropical and subtropical regions by using the NCEP/NCAR monthly reanalysis data from 1948 to 2012, based on the NCAR CAM 3.0 general circulation model. The results show that: 1) the intensity of SAH represents a remarkable interdecadal variation characteristic, the intensity of SAH experienced from weak to strong at the late 1970 s, and after the late 1970 s, its strength is enhanced and the area is expanded in the east-west direction.The expansion degree is greater westward than eastward, while it is opposite in summer. 2) Corresponding to the interdecadal variation of SAH intensity, after the late 1970 s, the divergent component of wind field has two ascending and three descending areas. Of the two ascending areas, one is located in the East Pacific, the other location varies with the season from the Indian Ocean in winter to the South China Sea and West Pacific in summer. Three descending areas are located in the north-central Africa, the East Asia and the Middle Pacific region respectively. 3) Corresponding to the interdecadal variation of SAH intensity, the rotational component of wind field at the lower level is an anomalous cyclone over the South China Sea and West Pacific in summer, while in winter, it is an anomalous cyclone over the Indian Ocean, and an anomalous anticyclone over the equatorial Middle Pacific. 4) Numerical simulations show that the interdecadal variation of SAH is closely related to the SST of the tropical and subtropical regions. The SST of Indian Ocean plays an important role in winter, while in summer, the SST of the South China Sea and West Pacific plays an important role, and the SST of the East Pacific also plays a certain role.
基金The present work is supported by National Science Foundation of China(41604138,41427901,41621063,41474133,41674158,41874179,41322030).
文摘The wavenumber spectral components WN4 at the mesosphere and low thermosphere(MLT)altitudes(70–10 km)and in the latitude range between±45°are obtained from temperature data(T)observed by the Sounding of the Atmosphere using Broadband Emission Radiometry(SABER)instruments on board the National Aeronautics and Space Administration(NASA)’s Thermosphere–Ionosphere–Mesosphere Energetics and Dynamics(TIMED)spacecraft during the 11-year solar period from 2002 to 2012.We analyze in detail these spectral components WNk and obtain the main properties of their vertical profiles and global structures.We report that all of the wavenumber spectral components WNk occur mainly around 100 km altitude,and that the most prominent component is the wavenumber spectral component WN4 structure.Comparing these long duration temperature data with results of previous investigations,we have found that the yearly variation of spectral component WN4 is similar to that of the eastward propagating non-migrating diurnal tide with zonal wavenumber 3(DE3)at the low latitudes,and to that of the semi-diurnal tide with zonal wavenumber 2(SE2)at the mid-latitudes:the amplitudes of the A4 are larger during boreal summer and autumn at the low-latitudes;at the mid-latitudes the amplitudes have a weak peak in March.In addition,the amplitudes of component WN4 undergo a remarkable short period variation:significant day-to-day variation of the spectral amplitudes A4 occurs primarily in July and September at the low-latitudes.In summary,we conclude that the non-migrating tides DE3 and SE2 are likely to be the origins,at the low-latitudes and the mid-latitudes in the MLT region,respectively,of the observed wavenumber spectral component WN4.
文摘Water quality of Litani River was deteriorated due to rapid population growth and industrial and agricultural activity. Multivariate analysis of spatio-temporal variation of water quality is useful to improve the projects of water quality management and treatment of the river. In this work, analysis of samples from different locations at different seasons was investigated. The spatio-temporal variation of physico-chemical parameters of the water was determined. A total of 11 water quality parameters were monitored over 12 months during 2018 at 3 sites located in different areas of the river. Multivariate statistical techniques were used to study the spatio-temporal evolution of the studied parameters and the correlation between the different factors. Principal Component Analysis (PCA) was applied to the responsible factors for water quality variations during wet and dry periods. The multivariate analysis of variance (MANOVA) was also applied to the same factors and gives the best results for both spatial and temporal analysis. A black point of agricultural, industrial and sewage water pollution was identified in Jeb-Jennine station from the high concentrations of ammonia, sulfate and phosphate. This difference was proved by the major changes in the values of the parameters from one station to the other. Jeb-Jennine represents a main pollution area in the river. The high ammonia, sulfate and phosphate concentrations result from the important agricultural, industrial and sewage water pollution in the area. A high bacterial activity was highlighted in Jeb-Jennine and Quaroun stations because of the presence of the high nitrite concentrations in the two locations. All parameters are highly affected by climate factors, especially temperature and precipitation. TDS, salinity, electrical conductivity and the concentrations of all pollutants increase during wet season affected by the runoff. Other factors can affect the water quality of the river for example geographical features of the region and seasonal human activity like tourism. The correlation between different parameters was evaluated using PCA statistical method. This correlation is not stable, and evolves between wet and dry season.
基金Projects supported by the National Natural Science Foundation of China (Grant Nos. 10775049 and 10375022)
文摘We present two kinds of exact vector-soliton solutions for coupled nonlinear Schrodinger equations with time- varying interactions and time-varying harmonic potential. Using the variational approach, we investigate the dynamics of the vector solitons. It is found that the two bright sol/tons oscillate about slightly and pass through each other around the equilibration state which means that they are stable under our modeh At the same time, we obtain the opposite situation for dark-dark solitons.