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Evidence from isotopic geochemistry as an indicator of eutrophication of Meiliang Bay in Lake Taihu, China

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Science China Earth Sciences 2006年第z1期49卷 62-71页

作者： LIN Lin, WU Jinglu & WANG Sumin nanjing institute of {2. & {3., Chinese Academy of Sciences, nanjing 2.0008, China Graduate University of the Chinese Academy of Sciences, Beijing 10003., China Chinese Acad Sci Nanjing Inst Geog & Limnol Nanjing 210008 Peoples R China Chinese Acad Sci Grad Univ Beijing 100039 Peoples R China

In this paper, Lake Taihu, a large shallow freshwater lake in China, is chosen as an example of reconstruction of eutrophication through the comparison between stable isotopes from dissolved nutrients and plants and water column nutrient parameters and integration of multiple proxies in a sediment core from Meiliang Bay including TN, TP, TOC, C/N, δ15N, δ13., etc. Differences in aquatic plant species and trophic status between East Taihu Bay and Meiliang Bay are indicated by their variations in δ13. and δ15N of aquatic plants and δ15N of NH4+. A significant influence ofexternal nutrient inputs on Meiliang Bay is reflected in temporal changes in δ 15N of NH4+ and hydro-environmental parameters. The synchronous change between δ13. and δ15N values of sedimented organic matter (OM) has been attributed to elevated primary production at the beginning of eutrophication between 1950 and 1990, then recent inverse correlation between them has been caused by the uptake of 15N-enriched inorganic nitrogen by phytoplankton grown under eutrophication and subsequent OM decomposition and denitrification in surface sediments, indicating that the lake has suffered from progressive eutrophication since 1990. Based on the use of a combination of stable isotopes and elemental geochemistry, the eutrophication of Meiliang Bay in Lake Taihu could be better traced. These transitions of the lake eutrophication respectively occurring in the 1950s and 1990s have been suggested as a reflection of growing impacts of human activities, which is coincident with the instrumental data.

关键词： stable carbon isotope of OM, stable nitrogen isotope, eutrophication, Lake Taihu.

Early Hydration of Composite Cement with Thermal Activated Coal Gangue

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Journal of Wuhan University of Technology(Materials Science) 2010年第1期25卷 162-166页

作者：郭伟 Department of Material Engineering Yancheng Institute of Technology institute of Material Science and Engineering Nanjing University of Technology

Composite cement samples were prepared by mixing clinker, gypsum with burnt coal gangues which was calcined at various temperatures. The mechanical strength and Ca（OH）2.content in the cement paste were tested, and the paste composition and microstructure were analyzed by thermogravimetry-differential thermal analysis （TG-DSC）, X-ray diffraction（XRD）, scanning electronic microscopy （SEM） and pore structure analysis. Results demonstrate that the thermal activated coal gangue could accelerate the early hydration of cement clinker obviously, which promotes the gangue hydration itself. The early hydrated products of the cement are C-S-H gel, Ca（OH）2.and AFt. The cement with 3.% （in mass） the gangue exhibits higher mechanical strength, and among all the cement samples the one with the gangue burnt at 700 ℃ displays the highest hydration rate, mechanical strength, the most gel pores and the lowest total porosity.

关键词： blended cement hydration microstructure hydration product

Spacial organization on the rural settlements in plain areas—taking Pinghu city in Zhejiang of China as an example

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Journal of Geographical Sciences 2000年第3期10卷 59-64页

作者： XUE Dong-qian1, YAO Shi-mou2. ZHANG Hong1 (1. Dept. of Tourism and Environment, Shaanxi Normal University, Xi’an 710062. China 2. nanjing institute of {2. and {3., Chinese Academy of Sciences, nanjing 2.0008, China)

This paper analyses the spacial distribution, quantity-scale, function-structure and facilities from the angle of spacial organizational optimizing theory and sustainable development thought. The authors point out the distributional principles of rural settlements in plain areas, and put forward planning and distribution of various levels of rural settlements (central villages, basic villages and natural villages).

关键词： plain area central villages basic villages natural villages spacial organization

MAJOR PROBLEMS OF SUSTAINABLE DEVELOPMENT ALONG THE BANK AREA OF THE CHANGJIANG RIVER

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Chinese Geographical Science 2000年第2期10卷 97-104页

作者： YANG Gui-shan(nanjing institute of {2. and {3.,the Chinese Academy of Sciences, Nanjng 2.0008, P R. China) nanjing institute of {2. and {3. the Chinese Academy of Sciences Nanjing P. R. China

Developing the Changjiang(Yangtze) River and building a developed economic zone along the bank area of the Chanajiang River is a great strategic decision of the national macroeconomic development distribution. This decision has both given an impetus to fast development of the regional economy and exacerbated the contradiction among economy and resources and environment. In this paper, some major problems ekisting in economic sustainable development, such as scattered industrial structure, duplicated construction of the great projects, enlarging the development gap of the regional economy and deteriorated environment etc., have been studied. The results show that scattered structure and duplicated distribution of some key industries and projects, especially automobile, electronics and petrochemical industry and communication, power installations, is one of the reasons for low industrial economic benefit; the great development gap among upper, middle and lower reaches areas are enlarging since the 1990’ s; soil erosion, nood disaster and environmental pollution are still exacerliating due to unreasonable over-development. Based on the above analysis, this paper brings out some countermeasures and proposals for increasing the ability of regional sustainable development, including transregional reorganization of industrial structure linking by assets and speeding the process of regional economy integration; gradually controlling and reducing the development gap arnong upper, middle and lower reaches areas through regional cooperation on a mutually beneficial basis; as well as strengthening ecological construction and environmental protection and increasing environmental bearing capacity etc.

关键词： the bank area of the Changjiang River sustainable development structure problems environment deterioration

Effects of main range and strength factors on change of COD in a shallow lake

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Journal of Environmental Sciences 1998年第1期10卷 51-57页

作者： Fan Cheng xin nanjing institute of {2. and {3.,Chinese Academy of Sciences,nanjing 2.0008,China

A model involving the relationship between non conservative matter (COD) and main range factors(loading, water stage) and strength factor (temperature) in a shallow lake has been established on the basis of less change of water stage area curve in certain extent, broader distribution in pollution sources and more homogeneous in quantity of heat. The effects of COD inflow and /or outflow, and hydro meterological factors upon COD content in Lake Taihu were calculated and simulated under the actual situation of the loadings and regimen. The results simulated by using the model are in better agreement with the observed field data. The error of the model was also discussed.

关键词： COD model environmental factor effects shallow lake.

Estimation of annual actual evapotranspiration from nonsaturated land surfaces with conventional meteorological data

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Science China Earth Sciences 2004年第3期47卷 239-246页

作者： QIU Xinfa1, ZENG Yan2. MIAO Qilong1 & YU Qiang2.1. Department of geography, nanjing {2. of Meteorology, nanjing 2.0044, China 2. {2. of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China nanjing Inst Meteorol Dept Geog Nanjing 210044 Peoples R China Chinese Acad Sci Inst Geog Sci Beijing 100101 Peoples R China Chinese Acad Sci Nat Resources Res Beijing 100101 Peoples R China

Views diverge greatly on the relationship between actual evapotranspiration (AE) and potential evapotranspiration (PE). Penman showed that AE is determined in intensity by PE and changes proportionally as a function of PE. In contrast, Bouchet indicated that AE deter-mines PE and varies inversely with PE. Based on nearly 3. years data from 43. weather stations and 512.hydrological stations in China, the two different theories, Penman抯 assumption and Bouchet抯 complementary relationship between AE and PE, were tested on nine river basins. With data integration technique, the complementary relationship between AE and PE was dis-played entirely. A general model to estimate the actual evapotranspiration from nonsaturated surfaces by routine meteorological observations has been established on the basis of thorough analysis of the concept of PE. The results show that the calculations are all in error control of <10%, except for a few years over the Yellow River Basin.

关键词： complementary relationship of evapotranspiration, potential evapotranspiration, actual evapotranspiration.

A general model for estimating actual evaporation from non-saturated surfaces

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Journal of Geographical Sciences 2002年第4期12卷 479-484页

作者： QIU Xinfa1,2. ZENG Yan3. LIU Changming3.1. Dept. of Urban && Resource Science, {2. University, {2. 2.0093. China 2. Dept. of {2., {2. institute of Meteorology, {2. 2.0044, China 3. Inst. of Geographic Sciences and Natural Resources Dept. of Urban & Resource Science Nanjing University Nanjing China Dept. of geography Nanjing Institute of Meteorology Nanjing China Inst. of Geographic Sciences and Natural Resources Research CAS Beijing China

Based on energy balance equation and mass transfer equation, a general model to estimate actual evaporation from non-saturated surfaces was derived. Making use of two concepts, “relative evaporation” and “relative drying power”, a relationship was established to account for the departure from saturated conditions. Using this model, the actual evaporation (evapotranspiration) can be calculated without the need of potential evaporation estimation. Furthermore, the model requires only a few meteorological parameters that are readily and routinely obtainable at standard weather stations. Based on nearly 3. years data of 43. meteorological stations and 512.hydrological stations in China, in combined with GIS, nine typical river basins were selected. Using the data of the selected river basins, the model was tested. The results show that the actual evaporation rate can be estimated with an error of less than 10% in most areas of China, except few years in the Yellow River Basin.

关键词： potential evaporation actual evaporation

Nutrient fluxes induced by disturbance in Meiliang Bay of Lake Taihu

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Science China Earth Sciences 2006年第z1期49卷 186-192页

作者： LUO Liancong, QIN Boqiang, ZHU Guangwei, SUN Xiaojing, HONG Dalin, GAO Yajun & XIE Rui nanjing institute of {2. & {3., Chinese Academy of Sciences, nanjing 2.0008, China nanjing Hydraulic Research institute, Ministry of Water Resources, nanjing 2.002., China 1. nanjing institute of {2. & {3. Chinese Academy of Sciences Nanjing 210008 China2. Nanjing Hydraulic Research Institute Ministry of Water Resources Nanjing 210024 China

A wave flume experiment was conducted to study nutrient fluxes at water-sediment interface of Meiliang Bay under different hydrodynamic conditions. The results reveal that hydrodynamics has remarkable effects on nutrient fluxes in this area. With a bottom wave stress of 0.019 N m-2.(equivalent to disturbance caused by wind SE 5-7 m s-1 at the sediment sample site of Meiliang Bay), the fluxes of TN, TDN and NH4+-N were separately 1.92. 10-3. -1.81 × 10-4 and 5.2.× 10-4 mg m-2.s-1(positive for upward and negative for downward), but for TP, TDP and SRP, the fluxes were 5.69 × 10-4, 1.68 × 10-4 and -1.2. × 10-4 mgm-2.s-1. In order to calculate the released amount of nutrients based on these results, statistic analysis on the long-term meteorological data was *** result shows that the maximum lasting time for wind SE 5-7 m s-1 in this area is about 15 h in summer. Further calculation shows that 111 t TN, 3. t NH4+-N, 3. t TP and 10 t TDP can be released into water (the sediment area was 47.45% of the whole surface area), resulting in concentration increase of 0.02., 0.007, 0.007 and 0.002.mg L-1 separately. With stronger disturbance (bottom wave stress is 0.2.7 N m-2.which is equivalent to disturbance caused by wind SE 10-11 m s-1 at the same site), there has been significant increase of nutrient fluxes (1.16× 10-2. 6.76×10-3. 1.14× 10-2.and 2.14× 10-3.mgm-2.s-1 for TN, DTN and NH4+-N and TP). The exceptions were TDP with flux having a decrease (measured to be 9.54× 10-5 mgm-2.s-1 ) and SRP with flux having a small increase (measured to be 5.42.× 10-5 mgm-2.s-1). The same statistic analysis on meteorological data reveal that the maximum lasting time for wind SE 10-11 m s-1 is no more than 5 h. Based on the nutrient fluxes and the wind lasting-time, similar calculations were also made suggesting that 2.0} t TN, 13..9 t TDN, 2.8 t NH4+-N, 42.7 t TP, 2.0 t TDP and 1.1 t SRP will be released from sediment at this hydrodynamic condition resulting in the concentration

关键词： hydrodynamics disturbance water-sediment interface nutrient release flux Lake Talhu.

Gene flow from transgenic oilseed rape (Brassica napus L.) to cruciferous weeds under mentor pollen inducement

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Progress in Natural Science:Materials International 2007年第11期17卷 1284-1289页

作者： Zhao Xiangxiang1,2. Luo Yuming1, Lu Weiping2. Qi Cunkou3. Pu Huiming3.and Wang Youping2.1. Biotechnology Key Laboratory of Eco-agriculture in Hongze Lake Region, Jiangsu Province, Huaiyin Normal College, Huai'an 2.3.01, China 2. Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou 2.5009, China 3. institute of Industrial Crops, Jiangsu Academy of Agricultural Sciences, nanjing 2.0014, China) Biotechnology Key Laboratory of Eco-agriculture in Hongze Lake Region Jiangsu Province Huaiyin Normal College Huai'an 223001 China Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology Yangzhou University Yangzhou 225009 China institute of Industrial Crops Jiangsu Academy of Agricultural Sciences Nanjing 210014 China

The alien gene flow between genetically modified glyphosate-resistant rapeseed variety Q3.(Brassica napus L.) and four cruciferous weeds was studied under mentor pollen inducement. The results showed that when Thlaspi arvense L., Capsella bursa-pastoris (L.) Medic, Cardamine hirsuta L. and Rorippa palustris (L.) Besser were pollinated with mentor pollen, the mixed Q3.and the weed, pollen grains aggregated largely and germinated quickly, and the numbers of pollen tubes penetrating into the style and the ovary were greatly increased as compared with corresponding self-pollination groups. Twenty four to forty eight hours after pollination, several pollen tubes were observed to penetrate into the ovule via micropyle in each mentor combination. However, when the mentor progenies were analyzed by PCR, all of them showed negative for the Q3.herbicide-resistant gene. Collectively, these results indicated that crossing between T. arvense, C. bursa-pastoris, C. hirsuta, R. palustris (as female) and Q3.(as male) was highly incompatible and the herbicide-resistant gene could not flow from Q3.to these four weeds.

关键词： herbicide-resistant rapeseed cruciferous weeds mentor pollination aniline blue fluorescence gene flow