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土壤溶质运移特性研究进展

土壤通报 2003年第6期34卷 576-580页

作者：李广辉魏世强西南农业大学资环学院重庆北碚400716

可溶性化学物质(土壤溶质)在土壤中的运移和分布已成为近年来研究的热点。本文综述了近年来土壤溶质运移机理、吸附模型、溶质运移数学模型等方面的研究进展。

关键词：土壤溶质运移特性数学模拟可溶性化学物质土壤运移运移机理吸附模型溶质运移

Denitrification in Chongming east tidal flat sediment, Yangtze estuary, china

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Science china Earth Sciences 2006年第10期49卷 1090-1097页

作者： WANG Dongqi1,2, CHEN Zhenlou1,3. XU Shiyuan1,2, HU Lingzhen1 & WANG Jun1,2 1. college of resources & environment, East{3. Normal university, Shanghai 200062,{3. 2. State Key Laboratory of Estuarine and Coastal Sediment Dynamics and Morphodynamics, East{3. Normal university, Shanghai 200062,{3. 3. Key Laboratory of Geographical Information Science of Ministry of Education,East{3. Normal university,Shanghai 200062,{3. 1. college of resources & environment East China Normal University Shanghai 200062 China 2. State Key Laboratory of Estuarine and Coastal Sediment Dynamics and Morphodynamics East China Normal University Shanghai 200062 China 3. Key Laboratory of Geographical Information Science of Ministry of Education East China Normal University Shanghai 200062 China

From July 2003.to July 2004, samples were collected on Chongming Island east tidal flat every two months. The research showed that the nitrous oxide (N2O) production rate was very low in the water, Chongming east tidal flat (CM) sediment was the N2O source of the water. Sediment N2O natural production rate was between -0.08 and 1.74 μmolN·m-2·h-1. N2O natural production rate was higher in the summer. The difference of the N2O natural production rate in the different tidal flats, the correlation between the N2O natural production rate and the denitrification rate, and those with the temperature and DO indicate that middle tidal flat sediment denitrification was the main process of the N2O production, while in the low tidal flat sediment, the production of the N2O came from several processes of the nitrogen cycling. Tidal flat sediment denitrification reaction was stronger in summer and winter but relatively lower in the late autumn and early spring. Seasonal change of the sediment denitrification rate was wide, from 1.12 to 3..3. μmolN·m-2·h-1. Temperature, DO and the coactions of them had the prominent effect on the tidal flat sediment denitrification.

关键词： Yangtze estuary, tidal flat sediment, denitrification, nitrous oxide, effect factor.

Effect of Tillage System on Distribution of Aggregates and Organic Carbon in a Hydragric Anthrosol

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Pedosphere 2008年第5期18卷 574-581页

作者： GAO Ming LUO You-Jin WANG Zi-Fang TANG Xiao-Hong WEI Chao-Fu college of resources and environment Southwest University Chongqing 400716 （China）.

The effect of different tillage systems on the size distribution of aggregates and organic carbon distribution and storage in different size aggregates in a Hydragric Anthrosol were studied in a long-term experiment in chongqing,china. The experiment included three tillage treatments:conventional tillage with rotation of rice and winter fallow(CT-r) system,no-till and ridge culture with rotation of rice and rape(RT-rr) system,and conventional tillage with rotation of rice and rape(CT-rr) system. The results showed that the aggregates 0.02-0.25 mm in diameter accounted for the largest portion in each soil layer under all treatments. Compared with the CT-r system,in the 0-10 cm layer,the amount of aggregates > 0.02 mm was larger under the RT-rr system,but smaller under the CT-rr system. In the 0-20 cm layer,the organic carbon content of all fractions of aggregates was the highest under the RT-rr system and lowest under the CT-rr system. The total organic carbon content showed a positive linear relationship with the amount of aggregates with diameter ranging from 0.25 to 2 mm. The storage of organic carbon in all fractions of aggregates under the RT-rr system was higher than that under the CT-r system in the 0-20 cm layer,but in the 0-60 cm soil layer,there was no distinct difference. Under the CT-rr system,the storage of organic carbon in all fractions of aggregates was lower than that under the CT-r system;most of the newly lost organic carbon was from the aggregates 0.002-0.02 and 0.02-0.25 mm in diameter.

关键词： aggregates Hydragric Anthrosol organic carbon tillage system

Chemical and Biological Evaluation of Maturity of Pig Manure Compost at Different C/N Ratios

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Pedosphere 2001年第3期11卷 243-250页

作者： HUANG GUOFENG WU QITANG LI FANGBAI and J. W. C. WONG college of Natural resources and environment, South{3. agricultural university, Guangzhou 510642 (china) Department of Biology, Hong Kong Baptist university, Hong Kong (china) 华南农业大学广东 510642 香港浸会大学香港

Aerobic static pile composting (mechanical turning every 3.days) of pig manure was prepared at & m3.windrow heaps. Sawdust was used as the bulking agent to provide additional carbon and to increase the porosity of the substrate. Two treatments at initial C/N ratios of 3. and 15, respectively, were designed in the study. Dissolved organic carbon (DOC), soluble NH+4-N, C/N ratios in solid and aqueous phases, E4/E6 ratios, and seed germination index (GI) were determined to evaluate the maturity of the co-composts. Seed germination index, a biological parameter, was suggested as one of the most reliable maturity indicators for organic compost. The results showed that the treatment at the initial C/N ratio of 3. reached maturity after 49 days of composting; however, the treatment at the initial C/N ratio of 15 should require composting time of longer than 63.days to obtain maturation. Chemical multi-indicator evaluation was necessary, and the GI measurement was the recommended approach for maturity evaluation in the study.

关键词： C/N ratio composting maturity pig manure

Integrating MODFLOW and GIS technologies for assessing impacts of irrigation management and groundwater use in the Hetao Irrigation District,Yellow River basin

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Science china(Technological Sciences) 2009年第11期52卷 3257-3263页

作者： XU Xu1,2, HUANG GuanHua1,2 & QU ZhongYi3.1 Center for Agriculture Water Research, china agricultural university, Beijing 100083. china 2 Chinese-Israeli International Center for Research and Training in Agriculture, china agricultural university, Beijing 100083. china 3.Water Conservancy and Civil Engineering college, Inner Mongolia agricultural university, Hohhot 010018, china 1. Center for Agriculture Water Research China Agricultural University Beijing 100083 China 2. Chinese-Israeli International Center for Research and Training in Agriculture China Agricultural University Beijing 100083 China 3. Water Conservancy and Civil Engineering college Inner Mongolia Agricultural University Hohhot 010018 China

Due to severe water scarcity, water resources used in agricultural sector have been reduced markedly in Hetao irrigation district. Application of water-saving practices (WSPs) is required for the sustainable agricultural development. The human activities including WSPs and increase of groundwater abstraction can lower down the groundwater table, which is helpful to the salinity control. Meanwhile, an excessively large groundwater table depth may result in negative impact on crop growth and fragile ecological {3.. In this paper, the Jiefangzha irrigation system in Hetao irrigation district was selected as a typical area, a groundwater flow model based on ArcInfo Geographic Information System (GIS) was developed and implemented to quantify the effect of human activities on the groundwater system in this area. The preand post-processing of model data was performed efficiently by using the available GIS tools. The time-variant data in boundary conditions was further edited in Microsoft Excel with programs of Visual Basic for Application (VBA). The model was calibrated and validated with independent data sets. Application of the model indicated that it can well describe the effect of human activities on groundwater dynamics in Jiefangzha irrigation system.

关键词： groundwater flow modeling MODFLOW GIS water-saving practices irrigation district

Analysis and Modeling on the Spatial Structure of Urban Land Use: A Case of Jinan, china

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Chinese Journal of Population,resources and environment 2007年第2期5卷 34-40页

作者： Zhao Huixia1, 3. Zhang Zulu2, Jiang Luguang 1 1. Institute of Geographical Sciences and Natural resources Research, Chinese Academy of Sciences, Beijing 100101, china 2. college of Population, resources and environment, Shandong Normal university, Jinan Shandong 250014, china 3. Graduate School of the Chinese Academy of Sciences, Beijing 10003., china Institute of Geographical Sciences and Natural resources Research Chinese Academy of Sciences Beijing 100101 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China college of Population Resources and Environment Shandong Normal University Jinan Shandong 250014 China

Based on the data of urban land use obtained by remote sensing interpretation from aero images in 1986 and 2004, the spatial structure of Jinan is studied in this paper with the method of Geographic Information System (GIS). According to the proportion of land for residence, industry and commerce, the urban district can be distinguished into three rings. Compared with the traditional theory of the ring structure in Western coun- tries, they have many distinctive characteristics. The main func- tions of the inner ring include residence, business and banking, but the proportion of residential land (more than 50%) is considerably higher than that of the cities in Western countries. The land proportion for residence and industry in the intermediate ring is equal on the whole. The main land of the outside ring is for industrial use. From 1986 to 2004, great changes have taken place on the land proportion of different types of use. In the inner ring, the land for residential and industrial use has shrunk much while the land for commercial use has increased. In the intermediate ring, the changes of the three types of land use were not very much and the temporal variation was relatively stable. On the contrary, the structure in the outside ring varies acutely. Though most of it is also for industrial use, the proportion of residential land has in- creased much. The three rings can also be divided into several sectors respectively, according to the function of land use clusters. New trends and mechanisms of the changes of land use impacting the urban structure were proposed in the end of the paper.

关键词： urban land use ring structure sector structure Jinan

Experiment and mechanism of vibration liquefaction and compacting of saturated bulk solid

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Journal of Central South university of Technology 2001年第1期8卷 34-39页

作者： WU Ai xiang,GU De sheng,SUN Ye zhi,HU Hua (college of resources, environment and Civil Engineering, Central South {3., Changsha 410083. china) 1. college of resources Environment and Civil Engineering Central South University 410083 Changsha China

The paper studies the probability of industrial application of vibration liquefaction of bulk solid from the opposite point of view, and proposing turning its harmful effects into benefits. Utilizing a new device of vibration liquefaction and by compacting saturated bulk solid, a set of additional device for experiment was designed. These experiments examined the problems related to vibration liquefaction of fine ores and tailings on the basis of DSA 1 type direct shear apparatus, including models of straight tubes, curved tubes and a sandbox. The changing properties of tailings under vibration and the mechanism of vibration liquefaction and compacting of tailings were studied, and future application of the technique to mines has been put forward.

关键词： vibration liquefaction compacting mechanism

Study on Human Capital Valve Quantity Model and Investment Featuers

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Chinese Journal of Population,resources and environment 2005年第1期3卷 49-54页

作者： Chen Peian, Li Yujiang & Li Zhen Population, resources and environment college, Shandong Normal {3., Jinan Shandong 250014, china Population Resources and Environment College Shandong Normal University Jinan Shandong 250014 China

In this paper, human capital is considered a kind of goods in terms of investment. Basic consumption and profit margin are the two important components of human capital goods value. Compared with that of the material capital, the human capital consumption has the following features. The importance of human capital investment determined by the supply-demand mechanism, is growing gradually; The course of investment and return takes a long period of time; Human capital is characterized by strong technicality and weak negotiability; The investment profit margin is changeable and discriminating.

关键词： human capital value measure profit margin

Study on the double-logarithmic profile of tidal flow velocity in the near-bed layers

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Acta Oceanologica Sinica 2009年第6期28卷 84-92页

作者： NI Zhihui SONG Zhiyao WU Lichun southwestern Research Institute of Water Transport Engineering Chongqing Jiaotong UniversityChongqing 400016 China Key Laboratory of Virtual Geographic environment （Ministry of Education） Nanjing NormMUniversity Nanjing 210097 China State Key Laboratory of Hydrology-Water resources and Hydraulic Engineering Hohai UniversityNanjing 210098 China chongqing Education college Chongqing 400067 China

Tidal current velocity profile in the near-bed layers has been widely studied. The results showed that velocity profile in the near-bed layer obviously departure from the traditional logarithmic profile, due to the acceleration or deceleration. Although the logarithmic linear profile can reduce the rate of deviation from this, only it is a lower-order approximate solution. In this paper, considering the unsteady and non-linear features of tidal motion, the double logarithmic profile near-bed layers in estuarine and coastal waters is established on the assumption that the turbulent shear stress along the water depth was parabolic distribution, and on the basis of Prandtl＇s mixing length theory and yon Karman＇s self-similar theory. Having been verified the data observed at the West Solent in the south of England, and comparison of the logarithmic linear profile, it found that the double logarithmic profile is more precious than the latter. At last, the discussed results showed that：（1） The parabolic distribution of the tidal shear stresses verified good by the field data and experimental data, can be better reflected the basic features of the tidal shear stress deviating from linear distribution that is downward when to accelerate, upward when to decelerate. （2） The traditional logarithmic velocity profile is the zero-order approximation solution of the double logarithmic profile, the logarithmic linear profile is the first order, and the logarithmic parabolic profile is the second order. （3. Ignoring the conditions of diffusion and convection in the tida movement, the double logarithmic profile can reflect the tidal properties of acceleration or deceleration, so that the calculation of the friction velocity and roughness length are more reasonable. When the acceleration or the deceleration is about zero, the double logarithmic profile becomes the logarithmic profile.

关键词： turbulence shear stress tidal current double logarithmic profile near-bed layers friction velocity roughness length