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Retrospect and prospect of watershed hydrological model

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Communications in Nonlinear Science and Numerical simulation 2001年第3期6卷 172-177页

作者： B. CHEN, L. Z. XIA, Z. F. YANG and G. Q. CHEN state key {2. for Studies of Turbulence and Complex Systems / Center for environmental Sciences, peking university, beijing 100871, china Institute of environmental Sciences, beijing Normal Universitg, state key Lab. Studs. T./C.S. Center for Environmental Sciences Peking University Beijing 100871 China Institute of environmental Sciences Beijing Normal University Beijing 100875 China

A brief review is presented of the development of watershed hydrological models. Conventional Hydrological Model, Grey Hydrological Model, Digital Hydrological Model and Intelligent Hydrological Model are analyzed. The frameworks of Fuzzy Cognitive Hydrological Model and Integrated Digital Watershed Hydrological Model are presented.

关键词： watershed hydrological model digital watershed complex system

Urban environmental problems transition and environmental education towards sustainable cities in {2.

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Journal of environmental Sciences 2000年第1期12卷 20-23页

作者： LI Wei, XUE Ji\|yu (state key {2. laboratory of environmental simulation and pollution control, Institute of environmental Sciences, beijing Normal university, beijing 100875, {12.. E\|mail:WEILI@BNU.EDU.CN.{12.)

With the rapid economic development and the speeding up of urbanization, the urban environmental problems in china are experiencing a progressive transition, which is characterized by steady transferring to the living (or consumption) oriented {2. pattern from the production oriented {2. pattern. Regarding this transition, the environmental education recognized as an important measure for approaching the objective of sustainable development, should transfer its focus correspondingly in urban area, which is to transfer to the habit cultivating pattern on the basis of the traditional knowledge inputting environmental education pattern. In practice, the urban environmental education should emphasize more on developing or cultivating the sustainable living mode of the urban residents, especially the students in elementary and primary schools and women. By this transform, the environmental education may be guided further towards sustainable development, and to serve the achievement of sustainable cities better in china.

关键词： environmental education sustainable cities transition transform CLC number: X2. Document code: A

EXPERIMENTS ON SELF-PURIFICATION OF HEAVY METALPOLLUTANTS IN NATURAL RIVERS

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Journal of Hydrodynamics 1999年第1期11卷 20-32页

作者： Huang Sui-liang (Water Environment simulation laboratory, {2. key joint laboratory of environmental simulation and pollution control, beijing Normal university, beijing 100875,P. R. china) Wan Zhao-hui (Deportment of Sedimentation Engineering, china Ins

This paper is concerned with the experiments of simulating self-purification of heavy metal pollutants in natural rivers, such as tributaries polluted by heavy metal polutants joining a main stream, or an uncontaminated tributary with much sediment entering a main stream polluted by heavy metal pollutants, and the experiments on the effect of sediment movement on the adsorption of heavy metal pollutants. Further-more, the effect of turbulence, sediment supply conditions and sediment motion patterns on the adsorption of heavy metal pollutants are studied in a device, in which turbulence is generated by a harmonically vibrating set of grids. The results indicate that sediment motion pattern has no effect on the characteristic parameters in the adsorption isotherm, such as the saturated adsorption content by unit weight of seidment and the constant of adsorption-desorption rate in the Langmuir adsorption isotherm, but it has significant effect on the coefficient of adsorption rate (or the coefficient of desorption rate). When the turbulent intensity of flow is low and all sediment exists as bottom mud, the coefficient of adsorption rate of sediment (or the coefficient of desorption rate of sediment) is very small, thus descending rate of concentration of dissolved heavy metal pollutant concentration is small, and when the turbulent intensity of flow is high, sediment supply condition, that is, whether sediment exists on the bed or not, influences greatly the variation of dissolved heavy metal pollutant concentration. When the sediment on the bed could be lifted up, descending rate of dissolved heavy metal pollutant concentration is large. In other wards, the coefficient of adsorption rate (or the coefficient of desorption rate) by unit weight of suspended sediment is much larger than that by unit weight of bottom mud.

关键词： simulation experiment sediment heavy metal pollutants natural rivers water-sediment-pollutant interaction

Source Apportionment of Primary and Secondary Organic Aerosols at Urban and Rural Locations of beijing

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Source Apportionment of Primary and Secondary Organic Aeroso...

Root Zone Microbial Populations, Urease Activities, and Purification Efficiency for a Constructed Wetland

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作者： Song Guo Min Hu* Qingfeng Guo and Xin Zhang state key {2. laboratory of environmental simulation and pollution control college of environmental Sciences and Engineering peking university beijing {12. 100871

Ambient sampling was conducted at an urban and a rural site of beijing during CAREbeijing-2.08 field campaign. Secondary organic tracers derived from isoprene, -pinene, -caryophyllene, and toluene were measured using gas chromatography-mass spectrometry. Measured biogenic and anthropogenic secondary organic sources contributed 32.5±15.9% at urban site and 35.4±14.1% at rural site to the total organics, respectively. Toluene, isoprene, - pinene, and -caryophyllene SOC accounted for 16.6±8.4%, 8.9±5.8%, 4.8±2.2. and 2.2.1.9% of total OC at PKU. At Yufa, isoprene and toluene SOC were the major secondary contributors to OC with the contributions of 14.1±8.5% and 13.9±8.9%. SOA formation mechanism was discussed. Procurers VOCs, O3 and ambient temperature had great effects on SOA formation, suggesting the importance of gas phase ozonation to SOA formation. The different correlations of SOA with O3 and temperature suggested the mechanisms may be different from day to night. Relative humidity had no correlation with SOA concentration, but particle water uptake and acidity did, and the responses of SOA increase to water content and acidity were linear, indicating aqueous reaction may be also important for SOA formation. Primary source from CMB model and secondary source from tracer method can explain 72.2.±9.6% and 80.2.10.5% of the measured OC at PKU and Yufa, respectively. About 1/5-1/4 of the OC was not clear about their sources up to current knowledge.

关键词： Biogenic Anthropogenic Secondary organic aerosol Source apportionment

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Pedosphere 2004年第3期14卷 401-404页

作者： LIANGWei WUZhen-Bin ZHANFa-Cui DENGJia-Qi Environmentsimulationandpollution{2.statekeyjointlaboratory DepartmentofEnvironmentalScienceandEngineeringTsinghuaUniversityBeijing100084（China） statekey{2.ofFreshwaterEcologyandBiotechnology InstituteofHydrobiologyChineseAcademyofSciencesWuhan430072（China）

In order to investigate the effects of microorganisms and their urease activities in macrophytic root zones on pollutant removal, four small-scale plots (SSPs) of vertical/reverse-vertical flow wetlands were set up to determine: a) the relationship between the abundance of microorganisms in the root zones and water purification efficiency; and b) the relationship between urease activities in the root zones and pollutant removal in a constructed wetland system. Total numbers of the microbial population (bacteria, fungi, and actinomyces) along with urease activities in the macrophytic root zones were determined. In addition, the relationships between microbial populations and urease activities as well as the wastewater purification efficiencies of total phosphorus (TP), total Kjeldahl nitrogen (TKN), biochemical oxygen demand in 5 days (BOD5), and chemical oxygen demand (COD) were also analyzed. The results showed that there was a highly significant positive correlation (r = 0.9772. P ＜ 0.01) between the number of bacteria in the root zones and BOD5 removal efficiency and a significant negative correlation (r = -0.9092. P ＜ 0.05) between the number of fungi and the removal efficiency of TKN. Meanwhile, there was a significant positive correlation (r -- 0.8830, P ＜ 0.05) between urease activities in the root zones and the removal efficiency of TKN. Thus, during wastewater treatment in a constructed wetland system,microorganism and urease activities in the root zones were very important factors.

关键词： macrophytic root zone microbial population purification efficiency ureaseactivity wetland

An united model and simulation of nitrogen transport, uptake and transformation in soil-crop system

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Journal of environmental Sciences 1998年第1期10卷 89-99页

作者： Wang Hong qi, Chen Jia jun state key {2. of environmental simulation and pollution control, Institute of environmental Science, beijing Normal university,beijing 100875, china Li Yun zhu Department of Soil and Water Science, Agricultu

Based on the simulation experiments of water and nitrogen transport, transformation and uptaking, under the condition of different cropping pattern of winter wheat in the greenhouse and the condition of different wastewater irrigation plan. An united computing model of crop growth, distribution of roots, water and nitrogen uptaking by roots and transformation in soil crop system was developed. Growth status of crops, root growth condition and water, nitrogen uptaking pattern by roots under different watering and N pollution conditions were simulated and analyzed due to the development of this mathematical model and the identification of parameters and boundary conditions in the greenhouse, so that it provided a primary computing method for selecting an efficient, productive watering and wastewater irrigating plan.

关键词： soil crop system nitrogen uptaking and movement mathematical model.

Effects of highway construction on soil quality in the Longitudinal Range-Gorge Region in Yunnan Province

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Science Bulletin 2007年第S2期 192-202页

作者： ZHAO ShuQing CUI BaoShan GAO LiNa LIU Jie state key {2. laboratory of environmental simulation and pollution control,School of Environment,beijing Normal university,beijing 100875,china

The Impact of highway construction upon surrounding ecosystems in the Longitudinal Range-Gorge Region of Southwestern china was detected based on field survey and experimental *** con- ducted a study on Dali(from Dali City to Lijiang City)provincial road,Dabao(from Dall City to Baoshan City)highway and Baolong(from Baoshan City to Longling County)highway in the Longitudinal Range-Gorge Region to detect the effect of highway construction on surrounding soil quality using the method of space-for-time substitution,and predicted remediation of surrounding soil *** results showed that:(1)The effect of highway construction on both natural and cultivated soil quality is significant,and the effect is more significant in the period of highway construction than the period of highway in use.(2.The effects of highway construction is more apparent on downslope than upalope, and effect range was 2.0 m on downslope,while 150 m on upalope.(3)Soil remediatlon is mainly related to effect extent of highway construction,highway service time,vegetation restoration,soil or- ganic matter and soil total nitrogen,among which,highway construction is the most Important factor.(4) When vegetation coverage can be restored to 30% of the original condition,soil quality can be remedied to 44% of the original condition after 10 years,indicating that soil fertility remediation is rather difficult once it is destroyed.

关键词： highway construction soil quality prediction of restoration Longitudinal Range-Gorge Region

Effects of the expressway on the soil-plant systems in the Longitudinal Range-Gorge Region

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Science Bulletin 2007年第S2期 203-212页

作者： ZHAO Hui CUI BaoShan BAI JunHong REN HuaLi state key {2. laboratory of environmental simulation and pollution control,School of Environment,beijing Normal university,beijing 100875,china

Taking Da-Bao expressway in the Longitudinal Range-Gorge Region(LRGR)as an example,the effects of the expressway on three kinds of soil-plant systems along the road are analyzed by seven types of Indexes,which are soil nutrient,heavy metals of soil,soil moisture and pH of soil,plant nutrient,heavy metal of plant and plant ***,through comparing typical sampling points and their contra- distinguished points,the effects of the expressway on single index is analyzed and discussed;sec- ondly,interactions among the expressway and all kinds of indexes are discussed with correlative analysis;finally,the range and intensity of effects on three systems are analyzed with gray related *** results show that 1)within the range of effect by expressway,the forms of expression of all indexes are different to the interference of expressway.2.Expressway can cause the accumulation of HMS and HMP,especially in the farmland system;and bring a little alkallzation of the soil,especially In the shrub system.3)Expressway is the most important Influencing factor of HMS,SM,HMP and PD in the forest and shrub systems,but only HMS and HMP in the farmland *** the indexes of in- significant correlation with road,expressway works indirectly through the effect chains of the system. Comparing with three kinds of soil-plant systems,effects mostly concentrate on the areas of 10 m from the expressway in the forest and farmland systems,and on the area of 30 m on the shrub system.

关键词： Longitudinal Range-Gorge Region expressway the soil-plant system correlation analysis gray related analysis

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 {2. of Water Environment simulation,School of Environment,beijing Normal university,beijing,100875,china. state key {2. 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 {2. 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 0.2. day^-1 and 0.15 day^-1 for branch streams and 0.5 day^-1 and 0.2. day^-1 for mainstreams, respectively in ZWN. With one-dimensional water quality simulation model, water {2. capacities were calculated to be 82.139 tons/yr for CODMn and 2.94 tons/yr for NH3-N in ZWN.

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