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SIMULATION OF NON-POINT POLLUTANTS EVOLUTION IN COASTAL PLAIN ISLAND-A CASE STUDY OF CHONGMING ISLAND

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Journal of Hydrodynamics 2008年第2期20卷 246-253页

作者： YIN Hai-long JIANG Wen-yan LI Jian-hua college of environmental science and Engineering Tongji University Shanghai 200092 China Department of environmental science East China Normal University Shanghai 200063 China

The coastal plain region usually shows the agricultural dominated industry mode, so more and more attention is paid to non-point pollutants discharge. In this study, the method for assessing the influence of non-point pollutants discharge on river water quality is probed which is concluded as follows：（1） Considering the costal plain island is characterized as nearly even elevation, the conventional gravitational runoff confluence method based on eight-point gravitational flowing directions （DS） is unable to compute the runoff confluence received by the surrounding rivers, so a new method of triangular confluence based on three-points of grid center and the river segments is presented. Further the equations of non-point pollutants loads estimation and non-point pollutants confluence on rivers are presented. （2） The integration mode of non-point pollutants model and river water quality model is presented so as to further assess the non-point pollutants contribution to river water quality. （3） With the Chongming Island, the third largest island in china, as an example, the above-mentioned equations are specified. For this island, the non-point pollutants loads are estimated and linked to the developed water quality model of the river network in the island, and further the non-point pollution evolution in river network is simulated. In this scenario, the non-point pollution contribution to river water quality over the whole island is clearly displayed, and the area where the river water quality is seriously influenced by non-point pollutants discharge is distinctly depicted. This scenario also shows the water quality contribution ratio of non-point pollution to point pollution can be in the range of 55.5% to 44.5% which proves the importance of non-point pollution control in costal plain islands.

关键词： non-point pollution runoffconfluence water quality model Chongming Island

Genotypic Differences in Grain Yield and Physiological Nitrogen Use Efficiency Among Rice Cultivars

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Pedosphere 2009年第6期19卷 681-691页

作者： ZHANG Ya-Li, FAN Jian-Bo, WANG Dong-Sheng and SHEN Qi-Rong2college of resources and environmental sciences, Nanjing Agricultural university, Nanjing 210095 (china) college of resources and environmental sciences Nanjing Agricultural University Nanjing 210095 (China)

Efficient use of N in agricultural practice can increase yield, decrease production costs and reduce the risk of environmental pollution. Effects of N fertilizer application rates on grain yield and physiological N use efficiency (PE) in relation to the accumulation and redistribution of biomass and N in rice (Oryza sativa L.) cultivars were studied at two experimental farms of Nanjing Agricultural university, Nanjing, china in 2004. Three high N use efficiency (NUE) rice cultivars (Wuyunjing 7, Nanguang and 4007) and one low NUE rice cultivar (Elio) with similar growth patterns were studied under seven N rates (0, 60, 120, 180, 240, 300 and 360 kg ha -1 ). Grain yield increased with the N application rate and attained plateau at 180 kg N ha -1 for rice cultivars at each site. Increasing N rate decreased PE for biomass and grain yield. Grain yield and PE of Elio were about 20% and 18% lower than those of high NUE cultivars. Differences in biomass, N accumulation and N redistribution were observed at the post-heading stage among rice cultivars with differing NUEs. The less reproductive tillers of Elio resulted in less demand for C and N during grain filling, thus leading to lower PE of Elio compared with the high NUE rice cultivars.

关键词： accumulation biomass N application rate redistribution

Calculating soil moisture by remote sensing and analyzing hydrologic cycle process in the Yellow River basin

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science china(Technological sciences) 2004年第z1期47卷 1-13页

作者： YANG Shengtian1 & LIU Changming1, 2 1. School of environmental sciences, Beijing Normal university, Beijing 100875, china 2. Institute of Geographic science and Natural resources Research, Beijing 100101, china School of environmental sciences Beijing Normal University Institute of Geographic science and Natural resources Research

Based on the AVHRR pathfinder remote sensing data, soil moisture, precipitation and evaporation during the period of 1982—1998, soil moisture of all layers of soil-profile (0—1 m) in the Yellow River basin over the 17 years are calculated by the remote sensing model of calculating soil water. The Yellow River basin is divided into seven subcatchments as control sections at the location of six hydrologic stations (Lanzhou, Toudaoguai, Longmen, Sanmenxia, Huayuankou and Lijin). After calculating soil moisture and obtaining runoff data and precipitation data, the dynamical features of hydrological cycle in the Yellow River basin are analyzed for the period from 1982 to 1988 using water balance method. The conclusions are as follows: It is feasible to calculate the soil water on the macro-scale, in the soil profile with temporal continuity by means of remote sensing and survey in land. Some values of the key water cycle factors in the Yellow River are obtained, which include the annual precipitation of 4000 km3, the evapotranspiration of 3000-3500 km3, and the soil moisture transformation of ?500- 500 km3. Consequently, we analyzed the process of the water cycle in the Yellow River over the 17 years, and the results show that the segment upstream of Lanzhou city is a relatively humid region, and the area of internal waters and the reaches of Shanshan is the most desiccated region. Therefore, the runoff in the depth process is intensive and the runoff-generating process is weak in more arid regions.

关键词： the Yellow River, soil moisture, remote sensing, hydrologic cycle.

Equations and their physical interpretation in numerical modeling of heavy metals in fluvial rivers

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中国科学：技术科学英文版 2010年第2期53卷 548-557页

作者： HUANG SuiLiang Numerical Simulation Group for Water Environment, Tianjin Key Laboratory of environmental Remediation and Pollution Control, Key Laboratory of Pollution Processes and environmental Criteria of the Ministry of Education college of environmental science and Engineering, Nankai university, Tianjin 300071, china Numerical Simulation Group for Water Environment Tianjin Key Laboratory of Environmental Remediation and Pollution Control Key Laboratory of Pollution Processes and Environmental Criteria of the Ministry of Education college of environmental science an

Based on the previous work on the transport-transformation of heavy metal pollutants in fluvial rivers, this paper presented the formulation of a two-dimensional model to describe heavy metal transport-transformation in fluvial rivers by considering basic principles of environmental chemistry, hydraulics, mechanics of sediment transport and recent developments along with three very simplified test cases. The model consists of water flow governing equations, sediment transport governing equations, transport-transformation equation of heavy metal pollutants, and convection-diffusion equations of adsorption-desorption kinetics of particulate heavy metal concentrations on suspended load, bed load and bed sediment. The heavy metal transport-transformation equation is basically a mass balance equation, which demonstrates how sediment transport affects transport-transformation of heavy metals in fluvial rivers. The convection-diffusion equations of adsorption-desorption kinetics of heavy metals, being an extension of batch reactor experimental results and a major advancement of the previous work, take both physical transport, i.e. convection and diffusion and chemical reactions, i.e. adsorption-desorption into account. Effects of sediment transport on heavy metal transport-transformation were clarified through three examples. Specifically, the transport-transformation of heavy metals in a steady, uniform and equilibrium sediment-laden flow was calculated by applying this model, and results were shown to be rational. Both theoretical analysis and numerical simulation indicated that the transport-transformation of heavy metals in sediment-laden flows with clay-enriched riverbed possesses not only the generality of common tracer pollutants, but also characteristics of transport-transformation induced by sediment motion. Future work will be conducted to present validation/application of the model with available data.

关键词： heavy metals transport-transformation water-sediment-pollutants interaction fluvial rivers numerical modeling

Phylogeny of Ptychostomum (Bryaceae,Musci) inferred from sequences of nuclear ribosomal DNA internal transcribed spacer (ITS) and chloroplast rps4

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Journal of Systematics and Evolution 2009年第4期47卷 311-320页

作者： ~(1,2)Chen-Ying WANG ~1Jian-Cheng ZHAO~* 1(college of Life science,Hebei Normal university,Shijiazhuang 050016,china) 2(Department of Life science,Zhengzhou Teachers college,Zhengzhou 450044,china) (college of Life science Hebei Normal University Shijiazhuang 050016 China) (Department of Life science Zhengzhou Teachers College Zhengzhou 450044 China)

The phylogeny of Ptychostomum was first undertaken based on analysis of the internal transcribed spacer(ITS)region of the nuclear ribosomal(nr)DNA and by combining data from nrDNA ITS and chloroplast DNA rps4 *** parsimony,maximum likelihood,and Bayesian analyses all support the conclusion that the reinstated genus Ptychostomum is not *** funkii(Schw(a|¨)gr.)*** (≡Bryum funkii Schw(a|¨)gr.)is placed within a clade containing the type species of Bryum,*** Hedw. The remaining members of Ptychostomum investigated in the present study constitute another well-supported clade. The results are congruent with previous molecular *** the basis of phylogenetic evidence,we agree with transferring *** Mü***.(≡***(Brid.)Turton≡Bryum archangelicum Bruch & Schimp.), Bryum lonchocaulon Mü***.,Bryum pallescens *** Schw(a|¨)gr.,and Bryum pallens *** Ptychostomum.

关键词： Bryum molecular phylogeny nuclear ribosomal DNA internal transcribed spacer sequences Ptychostomum rps4 sequences.

Analysis of Stillbirth in Different Types of Sows

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Agricultural sciences in china 2002年第6期1卷 702-706页

作者： CHU Ming-xing,WANG Ping-qing and WU Chang-xin( Institute of Animal science , Chinese Academy of Agricultural sciences , Beijing 100094 , P. R. china college ofBioengineering, chongqing university, chongqing 400044 , P. R . china college of Animal science and Technology,china Agricultural university, Beijing 100094 , P.R. china) Institute of Animal science Chinese Academy of Agricultural Sciences Beijing 100094 P. R. China college of Bioengineering Chongqing University Chongqing 400044 P. R . China college of Animal science and Technology China Agricultural University Beijing 100094 P. R . China

Statistical analysis was conducted on sow stillbirth traits of three mating types with 1686 litters including Erhualian, Large White and F1. The number of stillborn piglets per litter (NSB) in Erhualian, Large White and F1 averaged 0.87, 0.32, 0.72, and the percentage born alive (PBA) averaged 95.1%, 97.1% , 95.7% , respectively. The Erhualian pig with a higher litter size also had a higher stillbirth rate. The results of the variance analysis indicated that the mating type, parity, farrowing year X farrowing season interaction and the total number born had highly significant effects on both NSB and PBA in sows (P 0.05), and highly significant effects on PBA (P 23, the genetic correlation, phenotypic correlation and environmental correlation between them were -0.985, -0.947 and -0.942, respectively.

关键词： Sow Stillbirth environmental effect Genetic analysis

AN APPROACH TO SEPARATING THE CURRENT VELOCITY IN ESTUARINE AND COASTAL WATERS

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Journal of Hydrodynamics 2009年第4期21卷 512-519页

作者： NI Zhi-hui SONG Zhi-yao WU Li-chun State Key Laboratory of Hydrology-Water resources and Hydraulic Engineering Ocean College Hohai University Nanj ing 210098 China Key Laboratory of Virtual Geographic Environment Ministry of Education Nanjing Normal University Nanjing 210097 China chongqing Education college Chongqing 400067 China

In the near-shore waters, the actual flow is mainly induced by tide, wind and salinity, and the river water runoff should also be included as a component in the estuary waters. The interactions among these major components are very complicated. Many approaches were proposed to study isolated tide and wind-driven currents or run-off based on the measured velocity, with all its components taken as a whole. In this article, firstly, based on the actual hydrodynamic characteristics of estuarine and coastal waters, an approach is proposed to separate the measured velocity by considering the theoretical current velocity profiles and using the least squares method. The vertical structures of tidal, wind-driven currents, density current and runoff can be obtained as well as their proportions in the measured velocity. Then, this approach is applied to the analysis of velocity data obtained in the North Branch of Yangtze River estuary and of laboratory test data. The results are found to be satisfactory. Finally, this approach is used to separate the measured velocity in the South Branch of Yangtze River estuary, to determine not only the bed friction velocity and roughness height, but also the surface wind stress, and to estimate the wind velocity data above the water surface. The results show that this method is simple in principle, practical in use, and reasonable in obtained results. So it can be used to effectively analyze the field data.

关键词： tide wind-driven current density current river water runoff friction velocity roughness height velocity separation

Large eddies induced by local impulse at wall of boundary layer with pressure gradients

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Progress in Natural science:Materials International 2008年第7期18卷 873-878页

作者： Changgen Lu a,b,*, Weidong Caob, Yanmei Zhang b, Jintao Pengb a college of Atmospheric science, Nanjing university of Information science & Technology, Nanjing 210044, china b college of environmental science and Engineering, Hohai university, Nanjing 210098, china college of Atmospheric science Nanjing University of Information Science & Technology Nanjing 210044 China college of environmental science and Engineering Hohai University Nanjing 210098 China

Large eddies induced by local impulse at the wall with pressure gradients in the boundary layer was studied by direct numerical sim- ulations. The results show that the amplitude evolution, the high and low speed stripes, the formation of streamwise vortices, the ejection and sweeping, inflexions and distortion at the mean velocity profiles, as well as other characteristics, are consistent with the experimental and other numerical results. It is also found that large eddies are easy to be excited with adverse pressure gradient in the boundary layer, and the growth of amplitudes, formation of streamwise vortices and the influencing area etc., are much larger than those with favorable pressure gradient in the boundary layer. In contrast, large eddies are hardly to be induced through local impulse disturbance at the wall with favorable pressure gradients in the boundary layer.

关键词： Boundary layer Pressure gradients Impulse Large eddies

Pelagodictyon Clarke,a newly recorded nanodiatom genus for china

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Journal of Systematics and Evolution 2009年第2期47卷 179-182页

作者： 1,2Yang LI 2Ya-Hui GAO 1(Key Laboratory of Ecology and environmental science in Guangdong Higher Education,college of Life science,South china Normal university,Guang-zhou 510631,china) 2(School of Life sciences,Xiamen university,Xiamen 361005,china) Key Laboratory of Ecology and environmental science in Guangdong Higher Education College of Life Science South China Normal University Guangzhou 510631 China School of Life sciences Xiamen University Xiamen 361005 China

Marine nanoplanktonic diatoms have been frequently either underestimated or overlooked in phyto-plankton investigations due to their small size(2-20 μm),which allows most of them to pass through a regular phytoplankton net of 70-μm pore *** nanoplanktonic diatom classification,water samples(each 2000 mL) were collected from several representative sea areas of Chinese coast from May 2002 to May *** Clarke was identified as a newly recorded nanodiatom genus for china under transmission electron microscope(TEM).This genus is characterized by the delicate structure of the valve *** striae are seen to be formed by ribs with cross-ribs(frets) and the intervening spaces are occupied by polygonal cribra situated much close to the exterior face of the *** one species was found,i.e.,*** *** description of the taxonomic characteristics with TEM photographs of this species and its ecological habitat and distribution are given in this *** characteristics comparisons among several resembling genera were discussed.

关键词： china fret nanodiatom new record Pelagodictyon Stephanodiscaceae