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Spectral response of rice(Oryza sativa L.) leaves to Fe^(2+) stress

Science china(Life Sciences) 2009年第8期52卷 747-753页

作者： CHI GuangYu1,2,CHEN Xin1,SHI Yi1 & LIU XinHui3 1 key laboratory of Terrestrial Ecological Process,Institute of Applied Ecology,Chinese Academy of Sciences,Shenyang 110016,china 2 Graduate school of Chinese Academy of Sciences,beijing 100049,china 3 state key joint laboratory of environmental simulation and pollution control,school of environment,beijing normal university,beijing 100875,china key laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Graduate school of Chinese Academy of Sciences Beijing 100049 China state key joint laboratory of environmental simulation and pollution control School of Environment Beijing Normal University Beijing 100875 China

In the management of lake eutrophication,the regulation effect of Fe is considered,in addition to the controlling nitrogen-and phosphorus *** on the "Fe hypothesis",this paper tentatively applied plant spectral response to the remote sensing early-warning mechanism of lake eutrophication.A laboratory water culture experiment with rice(Oryza sativa L.) was conducted to study Fe uptake by plants and the chlorophyll concentration and visible-near infrared spectrum of vegetable leaves as well as their interrelations under Fe2+ *** spectral indices,i.e.,A1(integral value of the changes of spectral reflectivity in the range 460―670 nm under Fe2+ stress),A2(integral value of the changes of spectral reflectivity in the range of 760―1000 nm under Fe2+ stress) and S(blue-shift range of red edge curve under Fe2+ stress),were used to establish quantitative models about the relationships between the rice leaf spectrum and Fe2+ *** the increase of Fe2+ in a culture solution,the Fe content in rice plants increased,while the chlorophyll concentration in vegetative leaves *** spectral reflectivity of vegetable leaves increased in the visible light band but decreased in the near infrared band,and the blue-shift range of the red edge curve *** indices A1,A2 and S all had significant correlations with the Fe content in rice leaves,the correlation coefficient being respectively 0.951(P 0.96) and predict the Fe level in rice leaves.

关键词： rice(Oryza sativa L.) spectrum Fe2+ lake eutrophication

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Biodegradation of polycyclic aromatic hydrocarbons in sediments from the Daliao River watershed, china

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Journal of environmental Sciences 2009年第7期21卷 865-871页

作者： QUAN Xiangchun, TANG Qian, HE Mengchang, YANG Zhifeng, LIN Chunye, GUO Wei state key joint laboratory of environmental simulation and pollution control, school of environment, beijing normal university, beijing 100875, china. [a]state key joint laboratory of environmental simulation and pollution control School of Environment Beijing Normal University Beijing 100875 China

The Daliao River, as an important water system in Northeast china, was reported to be heavily polluted by polycyclic aromatic hydrocarbons （PAHs）. Aerobic biodegradations of four selected PAHs （naphthalene, phenanthrene, fluorene and anthracene） alone or in their mixture in river sediments from the Daliao River water systems were studied in microcosm systems. Effects of additional carbon source, inorganic nitrogen and phosphorus, temperature variation on PAHs degradation were also investigated. Results showed that the degradation of phenanthrene in water alone system was faster than that in water-sediment combined system. Degradation of phenanthrene in sediment was enhanced by adding yeast extract and ammonium, but retarded by adding sodium acetate and not significantly influenced by adding phosphate. Although PAHs could also be biodegraded in sediment under low temperature （5~C）, much lower degradation rate was observed. Sediments from the three main streams of the Daliao River water system （the Hun River, the Taizi River and the Daliao River） demonstrated different degradation capacities and patterns to four PAHs. Average removal rates （15 or 19 d） of naphthalene, phenanthrene, fluorene and anthracene by sediment were in the range of 0.062-0.087, 0.005-0.066, 0.008- 0.016 and 0-0.059 mg/（L.d）, respectively. As a result, naphthalene was most easily degraded compound, anthracene was the hardest one. In multiple PAHs systems, the interactions between PAHs influenced each PAH biodegradation.

关键词： biodegradation the Daliao River microcosm polycyclic aromatic hydrocarbon sediment

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A HIGH-ORDER-ACCURATE DIFFERENCE SCHEME WITH UNCONDITIONAL STABILITY FOR THE DIFFUSION EQUATION ON NONUNIFORM GRIDS

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Journal of Hydrodynamics 2001年第1期13卷 92-98页

作者： Wang Xuan, Yang Zhi-feng state key laboratory of environment simulation and pollution control, Institute of environmental Sciences, beijing normal university, beijing 100875, china[WT5”HZ] beijing normal Univ. Beijing 100875 China

WT5”BZ]A high-order-accurate difference scheme with unconditional stability is developed for the diffusion equation on nonuniform grids. The theoretical analysis shows that the accuracy of this scheme is between third order and fourth order, and fourth-order accuracy is achieved in the case of the same grid steps being used within the computational domain. Two numerical examples are given to demonst ate the advantages of the proposed scheme. Compared with the conventional difference scheme, more accurate numerical solution can be obtained by using the proposed scheme even with relatively larger grid sizes. It is also pointed out that the appropriate structure of the nonuniform grid can not only make the proposed scheme more practical, but lead to a solution superior to that for a uniform grid structure. [WT5”HZ]

关键词： ]finite difference scheme diffusion equation nonuniform grid high accuracy computational fluid dynamics

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Estimation methods of eco-environmental water requirements: Case study

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Science china Earth Sciences 2005年第8期48卷 1280-1292页

作者： YANG Zhifeng1,2, CUI Baoshan1 & LIU Jingling 1. school of environment, beijing normal university, beijing 100875, china 2. state key joint laboratory of environmental simulation and pollution control, beijing 100875, china 1. school of environment Beijing Normal University 100875 Beijing China 2. state key joint laboratory of environmental simulation and pollution control 100875 Beijing China

Supplying water to the ecological environment with certain quantity and quality is significant for the protection of diversity and the realization of sustainable development. The conception and connotation of eco-environmental water requirements, including the definition of the conception, the composition and characteristics of eco-environmental water requirements, are evaluated in this paper. The classification and estimation methods of eco-environmental water requirements are then proposed. On the basis of the study on the Huang-Huai-Hai Area, the present water use, the minimum and suitable water requirement are estimated and the cor-responding water shortage is also calculated. According to the interrelated programs, the eco-environmental water requirements in the coming years (2010, 2030, 2050) are estimated. The result indicates that the minimum and suitable eco-environmental water requirements fluc-tuate with the differences of function setting and the referential standard of water resources, and so as the water shortage. Moreover, the study indicates that the minimum eco-environmental water requirement of the study area ranges from 2.84×1010m3 to 1.02×1011m3, the suitable water requirement ranges from 6.45×1010m3 to 1.78×1011m3, the water shortage ranges from 9.1×109m3 to 2.16×1010m3 under the minimum water requirement, and it is from 3.07×1010m3 to 7.53×1010m3 under the suitable water requirement. According to the different values of the water shortage, the water priority can be allocated. The ranges of the eco-environmental water re-quirements in the three coming years (2010, 2030, 2050) are 4.49×1010m3?1.73×1011m3, 5.99×10m3?2.09×1011m3, and 7.44×1010m3?2.52×1011m3, respectively.

关键词： eco-environmental water requirements, assessment methods, Huang-Huai-Hai area.

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A HIGH-ORDER FINITE DIFFERENCE METHOD FOR UNSTEADY CONVECTION-DIFFUSION PROBLEMS WITH SOURCE TERM

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Journal of Hydrodynamics 1999年第2期11卷 97-102页

作者： Yang Zhi-feng Wang Xuan(state key laboratory of environment simulation and pollution control, Institute of environmental Sciences, beijing normal university, beijing 100875, P. R. china.) beijing normal Univ Beijing China

The convection and diffusion are the basic processes in fluid flow and heat& mass transfer. The upwind and evolution functions for the convection term are introduced to give a comprehensive transformation to one-dimensional unsteady convection-diffusion equation involving source term. The corresponding compact fourth-order finite difference methed is developed. With the trans formation, the authors overcome the difficultyin dealing with the convection term, and the high-order expression for the convection-diffusion term can be conveniently obtained. The proposed difference scheme with thefourth-order accuracy and unconditional stability can fully reflect the upwind and evolutioneffects of the convection. The calculated results show that the errors of the referencescheme are 600 or 6000 times those of the proposed scheme for the same computationalgrid. With the one time decrease of the space grid, the errors of the proposed scheme andthe reference scheme reduce about 20 times and 2 times respectively. It is evident that theaccuracy of the proposed scheme is remarkably higher than that of the reference scheme.

关键词： convection-diffusion compact difference method comprehensive transformation unsteady computational fluid dynamics

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Study on the interaction between engineering construction and ecosystem changes in the Longitudinal Range-Gorge Region

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Chinese Science Bulletin 2007年第A02期52卷 21-32页

作者： CUI BaoShan HU Bo ZHAI HongJuan WEI GuoLiang WANG Juan school of environment,beijing normal university state key joint laboratory of environmental simulation and pollution Contro,beijing 100875,china beijing normal Univ Sch Environm State Key Joint Lab Environm Simulat and Pollut Con Beijing 100875 Peoples R China.

这份报纸拿在作为主要科学问题设计构造和生态系统变化之间的相互作用。基于 DPSIR ( Drive-Press-state-Impact-Response )框架，这研究分析在从开车，出版社，状态，影响和反应的方面设计构造和生态系统变化之间的相互作用的通匝，向... 详细信息

这份报纸拿在作为主要科学问题设计构造和生态系统变化之间的相互作用。基于 DPSIR ( Drive-Press-state-Impact-Response )框架，这研究分析在从开车，出版社，状态，影响和反应的方面设计构造和生态系统变化之间的相互作用的通匝，向前带相互作用模型，相互作用情形分析方法和相互作用索引(开车反应索引， IIDR ，开车影响索引， IIDI ，影响反应索引，红外，影响索引， IIII )，并且预付相应计算模型和相互作用索引 sy 并且也，这份报纸采用不同相互作用索引到尊重影响在上和对设计建设的反应，并且作为例子在纵的范围峡区域(LRGR ) 拿 Manwan 水力发出的电力车站和道路交通建设分析并且验证相互作用模型。由建设的结果和 Manwan 水力发出的电力的操作的系统的分析，车站是分别地 3.67， 3.92， 14.35 和 0.35。没有在相互作用系统，和利用的通匝元素的显著变化水力发出的电力车站基于想象有益于地区性的环境和社会的持续发展没有考虑环境费用，散开效果，潜在的否定效果和潜力，水力发出的电力的回答驻扎建设。通过一些案例研究，我们造了的相互作用模型在相互作用显示出很好的实际价值量的分析并且相互作用索引系统构造。

关键词：纵向岭谷区工程结构生态系统变化特征

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Biogenic Isoprene Emission Mechanism from ^(13)CO_2 Exposure Experiments

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Chinese Chemical Letters 2002年第9期13卷 897-900页

作者： Min SHAO state joint key laboratory of environmental simulation and pollution control, Center for environmental Sciences, Peking university, beijing 100871 state joint key laboratory of environmental simulation and pollution control Center for Environmental Sciences Peking University Beijing 100871 China

Biogenic isoprene emissions have been believed to be from only photosynthesis processes in plant. However nocturnal isoprene emission from pine is detected. And by feeding 13CO2 to plants, it is found that both photos... 详细信息

关键词： Emissions volatile organic compounds (VOCs) 13C labeling isoprene.

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A MACRO-SCALE SEMI-DISTRIBUTED HYDROLOGICAL MODEL AND APPLICATION TO THE DATONG RIVER VALLEY

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Journal of Hydrodynamics 2005年第6期17卷 667-676页

作者： YANG Zhi-feng LIU Lu-liu SHEN Zhen-yao GORDON G. Huang state key laboratory of Water environmental simulation School of Environment Beijing Normal Uni- versity Beijing 100875 China National Climate Center Beijing 100081 China Faculty of Engineering University of Regina Canada

A daily distributed hydrological model was developed using routine hydro meteorological data on the basis of the raster DEM and land cover data. Then the model was used to model daily runoff of the Datong River Valley located in the upper catchment of the Yellow River Basin. The runoff comprises surface flow, subsurface flow and ground water flow. Evapotranspiration comprises canopy evaporation, snow sublimation and soil evapotranspiration. The infiltration to the soil was estimated with improved Green-Ampt model, and the potential evapotranspiration is estimated with Morton CRAE method, which only needs the routine meteorological data. simulation results and the comparison with semi distributed SLURP hydrological model show that the structure of the model presented herein is reasonable.

关键词： hydrological model Yellow River GIS runoff

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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 university,beijing,100875,china. [a] 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 82,139 tons/yr for CODMn and 2394 tons/yr for NH3-N in ZWN.

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

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Influence of fuel quality on vehicular NOx emissions

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Journal of environmental Sciences 2001年第3期13卷 265-271页

作者： WANG Shao xia, SHAO Min, ZHANG Yuan hang (state joint key laboratory of environmental simulation and pollution control, Center for environmental Sciences, Peking university, beijing 100871, china. state joint key laboratory of environmental simulation and pollution control Center for Environmental Sciences Peking University Beijing 100871 China.

The quality of gasoline and diesel fuel affects pollutant emissions from vehicles. By applying the COMPLEX model, developed by the US EPA and industry to relate fuel composition to vehicle emissions, this paper estimates the influence of improvements in gasoline quality to lower vehicular NOx emissions. A case study is performed for Guangzhou City that has NOx concentrations significantly above the national ambient air quality standards (NAAQS). The paper discusses the potential for reducing NOx in Guangzhou by improving the quality of gasoline.

关键词： Air quality Automotive fuels Gasoline

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