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Effects of PHC on Water Quality of Jiaozhou Bay Ⅰ. annual variation of PHC Content

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Meteorological and Environmental Research 2015年第11期6卷 31-34页

作者： Yang Dongfang Wang Fengyou Zhu Sixi Yang Xiuqin Long Mingzhong Research Center for Karst Wetland Ecology Guizhou Minzu University College of Chemistry and Environmental Science Guizhou Minzu University North China Sea Environmental Monitoring Center State Oceanic Administration

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.

关键词： PHC Content annual variation Water quality Jiaozhou Bay China

annual variation of Mineral Nutrition Elements Content in Macadamia integrifolia

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Agricultural Science & Technology 2014年第1期15卷 162-165页

作者：王文林赵大宣郑树芳覃振师韦持章黄锡云谭德锦赵静邱文武广西南亚热带农业科学研究所广西龙州532415

[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.

关键词： Macadamia integrifolia Mineral nutrition elements annual variation

Long-term daily water temperatures unveil escalating water warming and intensifying heatwaves in the Odra river Basin,Central Europe

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Geoscience Frontiers 2024年第6期15卷 321-335页

作者： Jiang Sun Fabio Di Nunno Mariusz Sojka Mariusz Ptak Quan Zhou Yi Luo Senlin Zhu Francesco Granata College of Hydraulic Science and Engineering Yangzhou UniversityYangzhouChina Department of Civil and Mechanical Engineering(DICEM) University of Cassino and Southern LazioVia Di Biasio4303043CassinoFrosinoneItaly Department of Land Improvement Environmental Development and Spatial ManagementPoznanUniversity of Life SciencesPia˛tkowska 94E60649 PoznanPoland Department of Hydrology and Water Management Adam Mickiewicz UniversityB.Krygowskiego 1061-680 PoznanPoland GIS Technology Research Center of Resource and Environment in Western China Yunnan Normal UniversityKunmingChina

Water temperature is a critical indicator and weathervane of aquatic ***,the vast majority of rivers lack long-term continuous and complete water temperature *** this study,ensemble models by combining NARX(nonlinear autoregressive network with exogenous inputs)and air2stream were used to reconstruct daily river water temperatures for 27 hydrological stations in the Odra River Basin,one of the largest river systems in *** each hydrological station,both the NARX and air2stream models were calibrated and validated,and the better-performed model was selected to reconstruct daily river water temperatures from 1985 to *** results showed that hybrid modeling by combining NARX and air2stream is promising for reconstructing daily river water *** on the reconstructed dataset,annual and seasonal trends of water temperature and characteristics of river heatwaves were *** results indicated that annual river water temperatures showed a consistent warming trend over the past 40 years with an average warming rate of 0.315C/*** river water temperatures indicated that summer warms faster,followed by autumn and spring,and winter river water temperatures showed an insignificant warming *** heatwaves are increased in frequency,duration,and intensity in the Odra River Basin,and 6 out of 27 hydrological stations have river heatwaves categorized as‘severe’and‘extreme’,suggesting that mitigation measures are needed to reduce the impact of climate warming on aquatic ***,results showed that air temperature is the major controller of river heatwaves,and river heatwaves tend to intensify with the warming of air temperatures.

关键词： River water temperature Ensemble modeling annual variation Seasonal pattern River heatwaves

Discovery of the Significant Impacts of Swell Propagation on Global Wave Climate Change

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Journal of Ocean University of China 2024年第3期23卷 594-604页

作者： ZHENG Chongwei Dalian Naval Academy Dalian 116018China Marine Resources and Environment Research Group on the Maritime Silk Road Dalian 116018China

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 *** 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 *** 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),*** increasing trend was mainly reflected after ***-ERA showed a trough in 1975(1.33 m)and a crest in 1992(1.83 m),which were not reflected in SWH-Mei.

关键词： wave climate climatic trend monthly variation annual variation external swell

variations of electron density and temperature in ionosphere based on the DEMETER ISL data

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Earthquake Science 2010年第4期23卷 349-355页

作者： Yufei He Dongmei Yang Rong Zhu Jiadong Qian M Parrot Institute of Geophysics China Earthquake Administration Beijing 100081 China Institute of Earthquake Science China Earthquake Administration Beijing 100036 China Laboratoire de Physique et Chimie de l'Environment Centre National de la Recherche Scientifique Orleans France

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.

关键词： seasonal variation annual variation spatial distribution Ne Te DEMETER satellite

Relation of ice conditions to climate change in the Bohai Sea of China

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Acta Oceanologica Sinica 2001年第3期20卷 331-342页

作者： Bai Shan, Liu Qinzheng, Wu Huiding I. National Center fOr Marine Environmnt FOrecats, ffeijing l(XX)8I. China. Natl. Center Marine Envrn. Forecasts Beijing 100081 China

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.

关键词： Sea ice annual variation seasonal evolution climatic factor the Bohai Sea

THE COMPARISON OF CHINESE AND EUROPEAN STREAM RUNOFF

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Journal of Geographical Sciences 1994年第Z1期4卷 102-109页

作者： Cheng Tianwen(Institute of Geography, CAS, Beijing 100101People’s Republic of China)

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 *** 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 *** 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.

关键词： stream runoff drainage basin water balance,distribution interannual variation annual variation

Analysis on Apparent Resistivity variations of Garzê Station before the 2013 Lushan M_S 7. 0 Earthquake

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Earthquake Research in China 2014年第3期28卷 388-402页

作者： Xie Tao Lu Jun Ren Yuexia Zhao Minyuan China Earthquake Networks Center Earthquake Administration of Sichuan Province Garzê Seismic Station

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.

关键词： Lushan earthquake Garze Seismic Station Apparent resistivity Trendincrease annual variation

A study of the ionogram derived effective scale height around the ionospheric hmF2

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A study of the ionogram derived effective scale height aroun...