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中国西部河谷型城市发展及其环境问题

山地学报 2004年第1期22卷 40-47页

作者：杨永春兰州大学资源环境学院甘肃兰州　73.000

分析了1949年以来中国西部河谷型城市的数目变化与空间分布、规模与职能变化。在此基础上,以西部部分河谷型城市为例,讨论了影响该类城市的环境污染和热岛效应等城市环境问题,并研究了环境问题的成因,认为工业化过程与城市化过程、地形... 详细信息

分析了1949年以来中国西部河谷型城市的数目变化与空间分布、规模与职能变化。在此基础上,以西部部分河谷型城市为例,讨论了影响该类城市的环境污染和热岛效应等城市环境问题,并研究了环境问题的成因,认为工业化过程与城市化过程、地形条件、工业的空间布局、建设用地结构不合理和城市建设的间接效应等是造成目前西部河谷型城市环境问题突出的主要原因。

关键词：中国西部河谷型城市环境问题

Displacement of Building Cluster Using Field Analysis Method

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Geo-Spatial Information Science 2003年第2期6卷 55-62页

作者： AI TinghuaAI Tinghua, associate professor, Ph.D, school of resource and environment Science, Wuhan {3., 129 Luoyu Road, Wuhan 43.079, china. school of resource and environment Science Wuhan University Wuhan China

This paper presents a field based method to deal with the displacement of building cluster, which is driven by the street widening. The compress of street boundary results in the force to push the building moving inside and the force propagation is a decay process. To describe the phenomenon above, the field theory is introduced with the representation model of isoline. On the basis of the skeleton of Delaunay triangulation, the displacement field is built in which the propagation force is related to the adjacency degree with respect to the street boundary. The study offers the computation of displacement direction and offset distance for the building displacement. The vector operation is performed on the basis of grade and other field concepts.

关键词：制图综合建筑群街道分界线三角测量扫描分析空间数据模型 GIS 地理信息系统

Parameter determination to calculate water environmental capacity in Zhangweinan Canal Sub-basin in china

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Journal of environmental Sciences 2010年第6期22卷 904-907页

作者： Yingxia Li ,Ruzhi Qiu,Zhifeng Yang,Chunhui Li,Jingshan Yu State Key Laboratory of Water environment Simulation,school of environment,Beijing Normal {3.,Beijing,100875,china. State Key Laboratory of Water environment Simulation School of Environment Beijing Normal University Beijing 100875 China

Zhangweinan canal sub-basin （ZWN） has the most serious water resource shortage and water pollution problems in north of china. To calculate the water environmental capacity in ZWN, determination methods for design flow rates and degradation coefficients were discussed in this study. Results showed that 90% and 50% hydrological guarantee flow rates were suitable to be the design flow rates for rainy and dry seasons, respectively. Degradation coefficients of CODMn and NH3.N were 0.25 day^-1 and 0.15 day^-1 for branch streams and 0.5 day^-1 and 0.25 day^-1 for mainstreams, respectively in ZWN. With one-dimensional water quality simulation model, water environmental capacities were calculated to be 82,13. tons/yr for CODMn and 23.4 tons/yr for NH3.N in ZWN.

关键词： degradation coefficient design flow rate water environmental capacity Zhangweinan

Preliminary study on assessment of nutrient transport in the Taihu Basin based on SWAT modeling

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Science china Earth Sciences 2006年第Z1期49卷 135-145页

作者： LAI Geying, YU Ge & GUI Feng Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing 210008, china The Graduate school of the Chinese Academy of Sciences, Beijing 10003., china Key Lab of Poyang Lake Ecological {3. and resource Development, Jiangxi Normal university, Nanchang 3.0027, china Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing China The Graduate school of the Chinese Academy of Sciences Beijing China Key Lab of Poyang Lake Ecological environment and resource Development Jiangxi Normal University Nanchang China

With the Taihu Basin as a study area, using the spatially distributed and mechanism-based SWAT model, preliminary simulations of nutrient transport in the Taihu Basin during the period of 1995～2002 has been carried out. The topography, soil, meteorology and land use with industrial point pollution discharge, the loss of agricultural fertilizers, urban sewerage, and livestock drainages were all considered in the boundary conditions of the simulations. The model was calibrated and validated against water quality monitoring data from 2001 to 2002. The results show that the annual total productions of nitrogen (TN) and phosphorus (TP) into Lake Taihu are 40000t and 2000t respectively. Nutrient from the Huxi Region is a major resource for Lake Taihu. The non-point source (surface source) pollution is the main form of catchment sources of nutrients into Lake Taihu,occupied TN 53. and TP 56% respectively. TN and TP nutrients from industrial point pollution discharge are 3.% and 16%, and sewerage in both forms of point source and non-point source are TN 3.% and TP 47%. Both the loss of agricultural fertilizers and livestock drainages from the catchment should be paid more attention as an important nutrient source. The results also show that SWAT is an effective model for the simulation of temporally and spatially nutrient changes and for the assessment of the trends in a catchment scale.

关键词： Taihu Basin, nutrients, catchment resource inputs, SWAT model, simulation.

Predicting octanol/water partition coefficient using solvation free energy and solvent-accessible surface area

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Journal of environmental Sciences 2001年第3期13卷 299-303页

作者： LIU Xin hui, WU Chun de, HAN Shuo kui, WANG Lian sheng(State Key Laboratory of Pollution Control and resource Reuse, Department of environmental Science, school of the environment, Nanjing university, Nanjing 210093. china.

The regression model for octanol/water partition coefficients ( K ow ), is founded with only two molecular descriptors available through quantum chemical calculations: solvation free energy (Δ G S ), and solvent accessible surface area (SASA). For the properties of 47 organic compounds from 17 types, the model gives a correction coefficient (adjusted for degrees of freedom) of 0 959 and a standard error of 0 277 log unit. It is a suitable way to predict the partition properties that are related to solute solvent interactions in the water phase.

关键词： solvation free energy solvent accessible surface area quantum chemical descriptor

Carbon isotopic characteristics and their genetic relationships for individual lipids in plants and sediments from a marsh sedimentary environment

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Science china Earth Sciences 2005年第8期48卷 1203-1210页

作者： DUAN Yi1, ZHANG Hui1, ZHENG Chaoyang1, WU Baoxiang1 & ZHENG Guodong2 1. lanzhou Institute of Geology, Chinese Academy of Sciences, lanzhou 73.000, china 2. Department of Earth & Planetary System Science, Graduate {3. of Science, Hiroshima university, Higashi-Hiroshima 73.-85Japan lanzhou Institute of Geology Chinese Academy of Sciences Lanzhou China Department of Earth & Planetary System Science Graduate School of Science Hiroshima University Higashi-Hiroshima Japan

The carbon isotopes of individual lipids in herbaceous plants and tree leaves in Ruoergai marsh were measured by the GC-IRMS analytical technique in order to understand the inherent relationships of carbon isotopes between sedimentary and plant lipids from typical marsh environment. The analytical results show that the carbon isotopic compositions of n-alkanes in different kinds of plants differ significantly. Mean δ 13. values of n-alkanes in her-baceous plants (?3..2‰―?3..9‰) are 3.3. lower than those in woody plant (?27.2‰― ?3..0‰). The carbon isotopic compositions of fatty acids in organisms (?3..3.― ?3..2‰) are very similar to those of n-alkanes and the δ 13. values for unsaturated fatty acids are within the range of those for saturated fatty acids. The differences in δ 13. values between plant lipids are obvious and range from 2.4‰ to 7.8‰. It is observed that the carbon isotopic compositions of sedimentary lipids are closely related to those of plant lipids. The carbon isotopic compositions (?27.0‰―?3..9‰) of n-alkanes, ≥C16 fatty acids, n-alkanols, sterols and n-alkanones in the sediments are similar to those of plant lipids and the carbon isotopic compositions of short-chain sedimentary lipids are similar to those of long-chain sedimentary homologues. These indicate that the sedimentary lipids are derived from high plants. However, the δ 13. values of C14:0 and C15:0 fatty acids in the sediments are lighter than those of the same carbon number saturated homologues in plants, reflecting the genetic features partially derived from bacteria. These data provide scientific evidence for carbon isotope-applied research of individual lipids.

关键词： marsh environment, plants, sediments, individual lipids, carbon isotopic compositions, genetic relationships.

Research on the damage of the Great Wall of Ming Dynasty in Beijing by remote sensing

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Science china(Technological Sciences) 2008年第S1期51卷 195-202页

作者： LI XiaoJuan,GONG HuiLi,ZHANG Ou,ZHANG WeiGuang & SUN YongHua The Key Lab of 3. Information Acquisition and Application,MOE,the Key Lab of Beijing resource Envi-ronment and GIS,and College of resource environment & Tourism,Capital Normal {3.,Beijing 10003.,china The Key Lab of 3. Information Acquisition and Application MOE the Key Lab of Beijing Resource Environment and GIS and College of Resource Environment & Tourism Capital Normal University Beijing China

Using aerial photos and high resolution satellite images of the year of 2004,this paper establishes remote sensing interpretation marks of the Great Wall of Ming Dynasty's damaged levels. Based on field survey and remote sensing survey in 1984,we analyzed present situation and changing characteristics being of the Great Wall of Ming Dynasty in Beijing. The results show that about 7.02% of the wall is well-preserved (about 25861 m); 3..5% of the wall is slightly or moderately dam-aged (about 115989 m); 61.5% of the wall is badly damaged (about 2263.9 m). This paper analyzes the dynamic change of the Great Wall of Ming Dynasty. It shows that the damaged situation of the Great Wall of Ming Dynasty in Beijing is serious. From 1984 to 2004,the well-preserved wall is decreased by 3.206 m (decreased by 56%); badly damaged wall increased by 51207 m (increased by 67%). Finally,this paper analyzes the influence factors of damaging Great Wall. The conclusion is as follows: The damaged Great Wall is generally near the roads and villages,small slope,and easily arriving land.

关键词： the Great Wall of Ming Dynasty remote sensing interpreting damage dynamic change spatial analysis

Ancient Changjiang channel system in the East china Sea continental shelf during the last glaciation

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Science china Earth Sciences 2005年第11期48卷 1972-1978页

作者： LI Guangxue1,2, LIU Yong1, YANG Zigeng3. YUE Shuhong4, YANG Wenda5 & HAN Xibin1 1. College of Marine Geo-science, Ocean university of china, Qingdao 266003. china 2. Shandong Key Laboratory of Sea Floor {3. and Exploration Technique, Qingdao 266003. china 3. Qingdao Institute of Marine Geology, Qingdao 266071, china 4. College of Marine environment, Ocean university of china, Qingdao 266003. china 5. First Survey Team of Marine Geology, Shanghai Bureau of Petroleum, Shanghai 201208, china College of Marine Geo-science Ocean University of China Qingdao China Shandong Key Laboratory of Sea Floor resource and Exploration Technique Qingdao China Qingdao Institute of Marine Geology Qingdao China College of Marine environment Ocean University of China Qingdao China First Survey Team of Marine Geology Shanghai Bureau of Petroleum Shanghai China

Based on the data of high-resolution seismic profiles, an ancient river channel sys-tem of the last glaciation occurred along the Zhedong and Xihu depression in the southeast of Hupijiao rise. The distribution of the channel fill system shows that the ancient Changjiang River went through the Changjiang depression into the low land plain of the outside continental shelf during the low sea level cycle of the last glaciation. The big channel fill into Okinawa Trough is not found due to the depletion of the river kinetic energy in the low land plain. The river discharge dispersal was of an important role to the dilution of the northern Okinawa Trough sea at that time. Six ancient river channel systems (A―F), which are main distributaries of ancient Changjiang in the East china Sea continental shelf during the last glaciation, may be buried off the modern Changjiang estuary. The distribution of these channels coincides with the zonal elevations in the sea floor.

关键词： last glaciation, continental shelf plain, Changjiang River, ancient channel fill

Microwave enhanced chemical reduction process for nitrite-containing wastewater treatment using sulfaminic acid

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Journal of environmental Sciences 2010年第1期22卷 56-61页

作者： Nan Li, Peng Wang, Qingsong Liu, Hailei Cao State Key Labaratory of Urban Water resource and environment, school of Municipal and environmental Engineering, Harbin Institute of Technology, Harbin 150090, china State Key Labaratory of Urban Water resource and environment School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China. E-mail: hhhkkk0994@***

High-concentration nitrite-containing wastewater that presents extreme toxicity to human health and organisms is difficult to be treated using traditional biological process. In this study, a novel microwave-enhanced chemical reduction process （MECRP） using sulfarninic acid （SA） was proposed as a new manner to treat such type of wastewater. Based on lab-scale experiments, it was shown that 75%-80% nitrite （NO2-） could be removed within time as short as 4 min under 50 W microwave irradiation in pH range 5-10 when molar ratio of SA to nitrite （SA/NO2-） was 0.8. Pilot-scale investigations demonstrated that MECRP was able to achieve nitrite and chemical oxygen demand （COD） removal with efficiency up to 80% and 20%, respectively under operating conditions of SA concentration 80 kg/m3. SA/NO2- ratio 0.8, microwave power 3.4 kW, and stirring time 3.min. Five-day biological oxygen demand （BODs）/COD value of treated effluent after MECRP was increased from 0.05 to 0.3. （by 620%）, which clearly suggested a considerable improvement of biodegradability for subsequent biological treatment. This study provided a demonstration of using microwave irradiation to enhance reaction between SA and nitrite in a short time, in which nitrite in wastewater was completely converted into nitrogen gas without leaving any sludge and secondary pollutants.

关键词： microwave-enhanced chemical reduction process nitrite-containing wastewater sulfaminic acid