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DIATOM COMMUNITY SUCCESSION AND NUTRIENT EVOLUTION RECORDED FROM A SEDIMENT CORE OF THE LONGGAN LAKE, A LARGE SHALLOW LAKE IN EAST china

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水生生物学报 2006年第6期30卷 702-710页

作者： DONG Xu-Hui and YANG Xiang-Dong (nanjing institute of {2. & limnology, the chinese academy of sciences, nanjing 210008, china) nanjing institute of {2. & limnology the Chinese Academy of Sciences Nanjing 210008

The Longgan Lake is a shallow mesotrophic macrophyte-dominated lake. According to the high-resolution diatom research from its sediment core, the diatom community succession was built, and the total phosphorus (TP) and chlorophyll-a (Chl-a) concentration were quantitatively reconstructed for the past 2.00 years, based on the diatom-TP and diatom-Chla transfer functions. The shifts of diatom assemblages also mirrored the developments of aquatic plant, reflecting the characters of aquatic ecosystem evolution. The inferred epilimnetic TP concentration fluctuated within a small range of 36 to 62.g/L, indicating the lake remained a relative stable mesotrophic status in the long historical period. The periodical variations of the diatom assemblage and trophic status suggest a mitigating function of shallow macrophyte-dominated lakes to nutrient input. The changes of lakes’ trophic status don’t linearly respond to the human disturbance in the catchment. The dynamics mechanism of phosphorus in macrophyte-dominated lakes, as inferred from diatoms, will provide a scientific foundation for the prediction of trophic status change in a shallow lake, as well as the lake ecological restoration and management decisions.

关键词： Diatom assemblage Nutrient Quantitative reconstruction Aquatic macrophyte Longgan Lake

Background contents of heavy metals in sediments of the Yangtze River system and their calculation methods

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Journal of Environmental sciences 1995年第4期7卷 422-429页

作者： Zhang Chaosheng, Zhang Shen, Zhang Licheng, Wang Lijun(institute of geography ,{2. , Beijing 100101 , china) Inst of geography Chinese Academy of Sci Beijing China China

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关键词： Yangtze River sediments heavy metalsi robust statistics data transformation.

Geochemical Forms of Phosphorus in Sediments of Three Large, Shallow Lakes of china

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Pedosphere 2006年第6期16卷 726-734页

作者： ZHU Guang-Wei QIN Bo-Qiang ZHANG Lu LUO Lian-Cong nanjing institute of {2. and limnology Chinese Academy of Sciences Nanjing 210008 China

A sequential extraction method for the fractionation of phosphorus （P） in lake sediments was used to analyze phos- phorus fractions of sediments taken from three large, shallow. eutrophic freshwater lakes of china-Talhu Lake. Chaohu Lake, and *** Lake. All three lakes are located in the lower reaches of the Changjiang River （Yangtze River）. In Taihu Lake and Chaohu Lake, algae blooms occurred every year, while Longgan Lake was a macrophyte-dominated lake. Results showed that exchangeable phosphorus fractions were much higher in the eutrophic lake sediments than in the macrophyte-flourishing lake sediment. Also, the ratio of Fe：P in the sediments of the algae-predomlnant lakes was generally much lower than that in the macrophyte-predominant lakes. Thus, the geochemical fractions of phosphorus in sediments had a closer relationship with the type of aquatic vegetation.

关键词： algal bloom macrophyte phosphorus sediment shallow lakes

Daily variation of carbon flux in soils of Populus euphratica forests in the middle and lower reaches of the Tarim River

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Progress in Natural Science:Materials International 2007年第5期17卷 584-590页

作者： Huang Xiang , Chen Yaning , Li Weihong , Ma Jianxin and Chen Yapeng (Xinjiang institute of Ecology and geography,{2., Urumqi 830011, china Graduate University,{2., Beijing 100039, china) [a]Xinjiang institute of Ecology and geography Chinese Academy of Sciences Urumqi China [b]chinese academy of {2. Graduate University Beijing China

In order to lucubrate the daily variation of respiration in soils of Populus euphratica forests and analyze its relationship with environmental factors in the middle and lower reaches of the Tarim River, the LI-8100 instrument of soil CO2.flux system was used to measure the parameters of soil carbon flux and air temperature 10 cm above ground surface along the profiles of Usyman, Archy River, Yengisu and Karday, and the relationships between the soil carbon flux and the soil moisture content were analyzed. The nonlinear regression analysis was carried out with the software SPSS13.0. We observed that: (1) soil respiration began to be restrained when the air temperature was up to 30℃10 cm above the ground surface; (2. the rates of soil respiration under the forests of Populus euphratica were significantly different at various moisture contents, the soil carbon flux was high along the Usyman profile, which has a high soil moisture content, and it was low along the profiles of Archy River, Yengisu and Karday, which has a low soil moisture content; (3) the exponential model can be used to explain the relationship between soil respiration and air temperature 10 cm above the ground surface. The average Q10 values along the profiles of Usyman, Archy River, Yengisu and Karday are 0. 61, 0.16, 0. 2. and 0. 35 respectively, much lower than the average of the world; (4) there is a positive correlation between the soil carbon flux and the soil moisture content.

关键词： Populus euphratica soil carbon flux air temperature 10 cm above ground surface soil moisture content the Tarim River.

SEDIMENT HAZARDS IN THE LOWER YELLOW RIVER

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International Journal of Sediment Research 1999年第2期14卷 25-30页

作者： SHI Changxing (Supported by the National Natural Science Foundation of china) (institute of {2., chinese academy of sciences, china)

The main sediment hazards in the lower Yellow River are flooding, channel erosion, desertification of cultivated lands, waterlogging. and soil salinization. Some of the hazards are the direct results of sediment movement and the others are related with sediment movement by the special landforms which themselves are the results of sediment movement. On the one hand, the sediment hazards,such as flooding. bank erosion and soil salinization, are aggravated by serious sediment accumulation in the Yellow River channel and irrigation canals due to heavy sediment load of the rived On the other hand, the distribution of the sediment deposit of different grain sizes is also a main factor influencing flooding, desertification, waterlogging and soil salinization hazards. The paper suggests to change the distribution of sedimentation as a measure of mitigating sediment hazards.

关键词： Sediment hazard The lower Yellow Rived Mitigation of sediment hazard

Geomorphologic evidence of phased uplift of the northeastern Qinghai-Tibet Plateau since 14 million years ago

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Science china Earth sciences 2004年第9期47卷 822-833页

作者： LU Huayu1, WANG Xiaoyong1, AN Zhisheng1, MIAO Xiaodong1, ZHU Rixiang3, MA Haizhou2. LI Zhen4, TAN Hongbing2.& WANG Xianyan1 1. State Key Laboratory of Loess and Quaternary Geology, institute of Earth Environment, chinese academy of sciences, Xi’an 710075{2. 2. Qinghai institute of Salt Lakes, chinese academy of sciences. Xining 810008,{2. 3. institute of Geology and Geophysics, chinese academy of sciences, Beijing 10002.,{2. 4. Department of geography, Qinghai Normal University, Xining 810008,{2. chinese Acad Sci Inst Earth Environm State Key Lab Loess & Quaternary Geol Xian 710075 Peoples R China chinese Acad Sci Qinghai Inst Salt Lakes Xining 810008 Peoples R China chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China Qinghai Normal Univ Dept Geog Xining 810008 Peoples R China

A typical sequence of fluvial terraces and aeolian deposits overlying these ter- races were multidisciplinary investigated. New evidences for uplift process of the northeastern Qinghai-Tibetan Plateau in the past 14 million years were obtained. At least 11 river terraces along Huangshui, the first-class tributary of Yellow River, at the Xining-Huzhu region are identi- fied. While the first one (T1) is classified as an accumulation terrace, the others are all basement river terraces, which consist of the Tertiary sandstone and siltstone bedrock, fluvial gravel and pebbles and the overlying aeolian loess-Red Clay deposit. Samples from the aeolian deposits were examined for paleomagnetic stratigraphic reconstruction (1030 samples), luminescence dating (16 samples), magnetic susceptibility and grain-size distribution (more than 4000 sam- ples). The luminescence dating and stratigraphic correlation suggest that terraces of Tll, T10, T8, T7, T3, T2. T1 were formed at 14, 11.3, 1.55, 1.2. 0.15, 0.07 and 0.01 million years ago, re- spectively. Sedimentological analysis and geomorphological observation indicate that formation and evolution of these terraces were mainly driven by tectonic uplift. Therefore, the terrace se- quence provides an ideal geological record, of the uplift process of the northeastern during the past 14 million years, and the timings of the terraces formation are regarded as the timings of tectonic uplift. The significant uplifting events took place at 14, 11.3, 1.2.and 0.15 mil- lion years ago, respectively. The fluvial incision at the Xining-Huzhu region is less than 100 m during a period of ~12.million years in the Miocene era (between the Tll and T9), while the Huangshui River had incised 432.m during the past 1.2.million years (from T7 to the present floodplain). The river incision process clearly demonstrates that accelerated rising of the north- eastern Qinghai-Tibet Plateau during the late Cenozoic, and provides new evidence of previous thoughts

关键词： river terrace, tectonic uplift, loess-Red Clay, the past 14 million years, northeastern Qinghai-Tibet Plateau.

The role of aerial algae in the formation of the landscape of the Yunnan Stone Forest,Yunnan Province, china

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Science china Earth sciences 2004年第9期47卷 846-864页

作者： TIAN Youping1,3, ZHANG Jie2. SONG Linhua1 & BAO Haosheng2.1. institute of Geographic sciences and Natural Resources Research,{2., Beijing 100101, china 2. Department of geography, nanjing University, nanjing 2.0093, china 3. School of Earth sciences and Resources, china University of Geosciences, Beijing 100083, china institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Department of geography Nanjing University Nanjing 210093 China School of Earth sciences and Resources China University of Geosciences Beijing 100083 China

Aerial algae on the surface of carbonate rocks at the Stone Forest, Shilin County, Yunnan Province, china, and their bioerosion were investigated in the field and studied in the laboratory in detail. Through the observation, identification and statistics of more than one hun- dred algal samples and rock samples with the optical microscopes (stereomicroscope, biological microscope) and the scanning electronic microscope (SEM), the relationships between erosional forms on the surface of the Stone Forest and algae and/or algal communities and the genetic mechanism for the formation of erosional forms were analyzed. It is suggested that aerial algae play an active role in bioerosive processes that may affect the formation of karst erosional forms. These effects include both direct and indirect ones. The direct effect is the initiative control (algal shape-controlling role) of algae on the formation of karst forms of various scales, mostly mi- cro-scale (<10-3m) and minor-scale (10-3-10-1m) erosional forms. The algal shape-controlling roles can be divided into the algal individual shape-controlling role and the algal community shape-controlling role. The former mostly controls the formation of micro-scale erosional forms, while the latter mostly controls the formation of micro-scale and smaller minor-scale erosional forms. The indirect effect refers to the promoting role of algae in the formation of karst forms, which may affect the formation of karst forms of all types and scales. The bioerosion of algae accelerates the weathering process of the whole Stone Forest karst landforms.

关键词： aerial algae, bioerosion, the Stone Forest, Yunnan Province, china.

The freeze-thaw metallogenic model of regenerated gold placers under cold low temperature conditions

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chinese Science Bulletin 1999年第S2期44卷 11-13页

作者： ZHANG Baolin~1, WANG Chunhe~2. WANG Jie~1 and SONG Changchun~2.1. institute of Geology and Geophysics, chinese academy of sciences, Beijing 10002.,{2. 2. Changchun institute of geography, chinese academy of sciences, Changchun 13002.,{2. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Changchun institute of geography Chinese Academy of Sciences Changchun 130021 China

LOCATED in the mined-out areas of primary gold placers, the regenerated gold placers in permafrost zonesare a kind of special low temperature deposit formed under modem cold climate conditions. Although theregeneration phenomenon was first discovered in South America, the scale and periodicity of the regeneration are more evident in permafrost environment of Northern Hemisphere.

关键词： regeneration gold placer freeze-thaw model.

INDUSTRIAL TRANSFORMATION OF SHENYANG CITY

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chinese Geographical Science 2003年第3期13卷 216-223页

作者： ZHANG Ping-yu(Northeast institute of geography and Agricultural Ecology,{2., Changchun 130012. P. R. china) Northeast institute of geography and Agricultural Ecology Chinese Academy of Sciences Changchun P. R. China

Industrial transformation represents a unique economic phenomenon in china’s regional economy, and old industrial city reconstruction has long been a key problem that affects state security. As a typical old industrial city in china, Shenyang established its heavy industrial city position in the First Five-year Plan period(1953-1957), and this industrial structure has been consolidated for a long time. After 1978, Shenyang began its long lasting industrial reconstruction in an all-round way by 3 main initiatives including restructuring economic system, upgrading traditional industrial technology and developing high-tech industry. In the end of the 1990s, it could be identified that remarkable structural changes took place in city economy at large as well as individual industrial sector. According to the GDP proportion change, Shenyang is on the way to a high level industrial structure. The secondary industry also engendered significant shifting as smelting and textile industry declined sharply but IT industry increased largely. Although the ratio of the heavy industry to the light industry changed periodically, the heavy industrial output value most time kept a high proportion over 60% of the gross industrial output value in the past five decades. Shenyang has favorable conditions for developing equipment manufacturing industry, but it should carry out the program by establishing its leading role in urban economy plan, building "Theme Industrial Parks", improving Tiexi Industrial Zone, removing any kind of system barrier, enlarging private and other ownerships economy and improving technology, marketing and management by IT application. In response to economy globalization, Shenyang needs to expand the cooperation worldwide and improve the cohesion with surrounding cities.

关键词： industrial transformation industrial structure urban development shenyang