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Sediment transferring function of the lower reaches of the Yellow River influenced by drainage basin factors and human activities

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Science China Earth Sciences 2005年第12期48卷 2194-2202页

作者： XU Jiongxin Institute of Geographical Sciences and Natural Resources Research ChineseAcademy of Sciences Beijing 100101 China

Sediment transferring function (Fs) of rivers is defined and indexed in this study, based on the concept of sediment budget at river reach scales. Then, study is made on the Fs of the lower reaches of the Yellow River in relation to natural and human factors in the drainage basin, such as the annual precipitation in different water and sediment source areas, proportion of >0.05 mm sediment of the total sediment load to the lower reaches of Yellow River, the regu-lated degree of the “clear” baseflow from the drainage area above Lanzhou, frequency of hy-perconcentrated flows, area of soil and water conservation measures in the drainage basin. As a result, a multiple regression equation has been established between Fs and 7 influencing factors, with multiple correlation coefficient r = 0.90. The reduction in annual precipitation in different water and sediment source areas has different effects on Fs. The reduction in annual precipitation in the area above Hekou Town and the area between Longmen and Sanmenxia results in a reduction in Fs, but the reduction in annual pre-cipitation in the area between Hekou Town and Longmen results in an increase in Fs. The grain size composition of sediment load strongly affects the Fs; the larger the proportion of >0.05 mm sediment in the suspended sediment load entering the lower reaches of the Yellow River is, the lower the Fs will be. Thus, if the Xiaolangdi Reservoir traps coarse sediment and releases fine sediment, Fs will be enhanced. This study also shows that the lower the proportion of high-flow season river flow to the annual total river flow at Lanzhou Station is, the lower the Fs will be. Therefore, the interception of large quantities of clear water by the reservoirs on the upper reaches of Yellow River is one of the major causes for the decrease in Fs in the lower reaches of the Yellow River.

关键词： river sediment, channel sedimentation, drainage basin factors, human activities, Yellow River.

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On LU Xun＇s Translation activities in the 1930s Viewed Through Bourdieu＇s Sociological Theory

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Sino-US English Teaching 2017年第7期14卷 446-449页

作者： XU Lan Ningbo Dahongying University Ningbo China

This paper intends to explore LI5 Xun＇s translation activities in the 1930s from the perspective of Bourdieu＇ssociological theory. It elaborates on his text selection and his strategy choice in particular and finds out that hisunique translation practice is determined by his translation habitus and the social and cultural context in his time.And the construction of his translation habitus is closely related with his life experiences, political stand, and loftypatriotism.

关键词： ' LU Xun's translation activities, field, habitus

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Measuring Inclinations and Attitudes of University Teachers towards Sports activities

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Journal of Sports Science 2015年第1期3卷 44-48页

作者： Shaimaa Abed Mutar A1-Tamimi College of Physical Education Department of practical sciences University of AI-Mustansiriyah Baghdad 00964 Iraq

The researcher wants to know the inclinations of the teachers in A1-Mustansiriyah University into participation in sports activities and the obstacles. The aims are to build measure of trends and tendencies toward university teachers about exercise and sporting activities and identify the reasons that prevent teachers from exercise. This measure contained on 25 open questions directed by the researcher toward the university teachers, and the distribution of the questions was on three areas： cognitive domain, behavioral domain and emotional domain. These areas have a relationship between tendencies and attitudes of teachers towards sports activities, in addition to the knowledge of the problems and obstacles that prevent this group from participating in sports activities. There is a lack of correlation between the desire to practice physical activity and the presence of a sports hall at the university in terms of statistics. The difficulties in the practice of sports activities, including economic, social and other factors, insecurity and instability exist. There is a good correlation between the previous practice of physical activity and the current desire to practice in terms of statistical activities.

关键词： Trends, tendencies, sport activities, method.

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A preliminary study on vegetation-erosion dynamics and its applications

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Science China Earth Sciences 2005年第5期48卷 689-700页

作者： WANG Zhaoyin 1,2 , WANG Guangqian 1 , LI Changzhi 1 & WANG Feixin 1 1. Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, China 2. International Research and Training Center on Erosion and Sedimentation, Beijing 100084, China Department of Hydraulic Engineering Tsinghua University Beijing China International Research and Training Center on Erosion and Sedimentation Beijing China

Vegetation-erosion dynamics is a new interdisciplinary science, studying the laws of evolution of watershed vegetation under the action of various ecological stresses. Introducing a qualitative expression of ecological stresses in this paper, the present authors establish the cou- pled differential equations for the vegetation-erosion process and derive a theoretical solution. The model is applied to the Anjiagou watershed on the Loess Pateau and the Xiaojiang water- shed and its sub-watersheds on the Yunnan Plateau. The calculated results agree well with the vegetation development processes. Abstracted from the differential equations the so-called vegetation-erosion chart is worked out, with which we can predict the development trend of vegetation under no human stresses. It is demonstrated that the erosion control is important for vegetation development and reforestation must be a long-term strategy. On the Yunnan Plateau with relatively high precipitation and temperature, vegetation can be greatly improved if erosion is controlled. On the dry and cold Loess Pateau suffering from high rate of soil erosion, however, vegetation can effectively control erosion but erosion reduction exhibits low effectiveness on vegetation development. Vegetation in the area is not stable and management is always needed to maintain the vegetation.

关键词： vegetation-erosion dynamics, human activities, coupled differential equations, erosion control, vigor ofvegetation.

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Variation characteristics of heavy metals and nutrients in the core sediments of Taihu Lake and their pollution history

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Science China Earth Sciences 2006年第Z1期49卷 82-91页

作者： LIU Enfeng SHEN Ji LIU Xingqi ZHU Yuxin WANG Sumin Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China

The sedimentary environment change, trophic evolution and heavy metals pollution history of the northern Taihu Lake in the last 100 years are studied according to the sedimentary geochemical proxies of the core sediments, such as grain size, nutrients, heavy metals, diatom, etc. The nutrients in the sediments depended mainly on the lake internal circulation and the heavy metals were from natural geogenic sources before the 1920s, which were not influenced by human activities generally, and grain size was one of the key factors influencing heavy metals content in the sediments.The alternation of manner and strength of human activities in Taihu Lake catchment before and after the 1920s made the lake sediments coarser, and hence heavy metals and TP content decreased contrasted with that before the 1920s. TP content in sediments and water increased from the 1950s to late 1970s due to anthropogenic pollutants discharge, and the lake belonging to mesotrophic state.TN and TOC content and C/N ratio increased due to the increasing external pollutants into Taihu Lake by human activities, TP content also increased obviously in water and sediments, and the diatom association was dominated by eutrophic species since the late 1970s, indicating the eutrophication state of Taihu Lake in this period. Meanwhile the increasing in heavy metals content, such as Cu, Mn,Ni, Pb and Zn, and their proportion of valid fractions in the sediments indicates that they all result from human pollutants since the late 1970s. The heavy metals in the surface sediments have certain potential biological toxicity due to the higher SEM/AVS ratio.

关键词： sediments, heavy metals, nutrients, human activities, pollution history, Taihu Lake.

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Studies on Antineoplastic Constituents from Marine Bryozoan Bugula neritina Inhabiting South China Sea (Ⅲ): Isolation and Structural Elucidation of Bryostatins 10,11 and 18

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Marine Science Bulletin 2001年第1期3卷 83-90页

作者：林厚文易杨华姚新生吴厚铭 School of Pharmacy Second Military Medical University Shanghai 200433 Department of Natural Products Shenyang Pharmaceutical University Shenyang 110015 China Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 Chinaix active compounds are isolated from the marine bryozoan Bugula neritina inhabiting the Nanwan Bay in the South China Sea using the bioassay-guided method with a combination of extraction and partitionation with suitable solvents as well as multiple column chromatographies ( Sephadex LH-20 ODS and preparative HPLC ). Their structures are identified as known bryostatins- bryostatins 4 5 6 10 11 and 18 through intensive analysis of the data of high resolution 2D NMR (600 MHz DQF-COSY TOCSY HMQC and ROESY) and ESI-MS. Among them bryostatins 10 11 and 18 are for the first time obtained from this bryozoan in the South China Sea and they show significant antineoplastic activities in vitro.

Six active compounds are isolated from the marine bryozoan Bugula neritina,inhabiting the Nanwan Bay in the South China Sea, using the bioassay-guided method with a combination of extraction and partitionation with suitable solvents as well as multiple column chromatographies ( Sephadex LH-20, ODS and preparative HPLC).Their structures are identified as known bryostatins-bryostatins 4, 5, 6, 10, 11 and 18 through intensive analysis of the data of high resolution 2D NMR (600 MHz, DQF-COSY,TOCSY, HMQC and ROESY) and ESI-MS. Among them, bryostatins 10, 11 and 18 are for the first time obtained from this bryozoan in the South China Sea and they show significant antineoplastic activities in vitro.

关键词： Bugula neritina, antineoplastic activities, bryostatins

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LUCC and Accompanied Soil Degradation in China from 1960's to 1990's

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Global Geology 2002年第1期7卷 62-71页

作者： JIANG Qigang(College of Earth Sciences, Jilin University, Changchun 130026, P. R. China) Shintaro GOTO and Hiroki TAKAMURA(Faculty of Geoenvironmental Science, Rissho University, Saitama, 360-0194, Japan) College of Earth Sciences Jilin University Changchun130026 P. R. China Faculty of Geoenvironmental Science Rissho University Saitama 360-0194 Japan

This paper tries to qualitatively analyze land use and cover changes (LUCC) and accompanied soil degradation in China, the data of World Atlas of Agriculture in 1969, Land Cover Data of Asia in 1992 and Global Assessment of Human Induced Soil Degradation in 1992, etc. have been used. From 1960' s to 1990's, the area of forestland had increased, arable land and paddy as well as grassland had significantly decreased in China. The major type of soil degradation is due to water erosion, which is widely distributed especially in Loess Plateau and in Southeast and Southwest China, this happened in forestland, grassland and arable land and mainly resulted from deforestation. The secondary type is wind erosion, which is mainly distributed in Northwest China, it happened in arable land and grassland and was caused by overgrazing. Chemical deterioration is distributed in North and Northwest China, which happened in paddy, arable land and grassland. Physical deterioration only concentrated in local area in North China, it happened in arable and paddy. Chemical and physical deteriora-tion mainly resulted from unreasonable activity. Because of different human activities, different LUCC and different natural conditions, the types and strength of soil degradation can be different.

关键词： LUCC, Soil degradation, Human activities, China

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