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Application of Equilibrium Partitioning Approach to the Derivation of Sediment Quality Guidelines for Metals in Dianchi Lake

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Pedosphere 2007年第3期17卷 284-294页

作者： CHEN Yun-Zeng YANG Hao ZHANG Zhen-Ke QIN Ming-Zhou JIN Feng LU Jun-Jie institute of resources and {2. Henan University Kaifeng 475001 （China） state key {2. of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of SciencesNanjing 210008 （China） College of Geography Nanjing Normal University Nanjing 210097 （China） key laboratory of Coast and Island Development of MOE Nanjing University Nanjing 210093 （China）

For the past 2. years, numerous studies have been carried out on the application of equilibrium partitioning approach （EqPA） for the derivation of sediment quality guidelines （SQGs）. However, for metals, few Equilibrium-partitioning- based numerical SQGs have been developed or are currently available because of the confounding factors mediating the bioavailability of metals. A study was conducted at Dianchi Lake, which is a heavily eutrophicated lake on the Yunnan- Guizhou Plateau, China with the focus on the measurement of partitioning coefficient （Kp） and SQGs derivation and normalization to acid volatile sulfide （AVS）, fine material, and organic carbon. Using new normalization methods, SQGs were formulated for seven metals including copper, zinc, lead, cadmium, chromium, mercury, and arsenic in Dianchi Lake. In Dianchi Lake sediments, the fine material contributed 2..4%-36.0% to the SQG values, with the largest contribution to the SQG value of mercury; AVS contributed 2.9%-75.0% to the SQG values, with the largest contribution to the SQG value of cadmium. This indicated that the fine material and the AVS were the most important controlling factors to the bioavailability of mercury and caximium, respectively. The contribution of total organic carbon （TOC） to the SQG values of copper and leaxi was 3.8% and 7.1%, respectively, indicating that at relatively lower concentrations, the contribution of TOC was not significant. In addition to normalization methods, appropriate procedures for the application of EqPA including sample collection, storage, and analysis are also essential to improve the reliability of SQGs. The normalized Dianchi Lake SQGs were higher than most of the empirically based SQGs developed in North America, but lower than Hong Kong interim SQGs except for cadmium and arsenic. The differences could be attributed to the approaches used for derivation of SQGs and the water quality criteria adopted and the differences in the physical and chemical charac

关键词： acid volatile sulfide fine material normalization method organic carbon sediment quality guidelines

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UU_* filtering of nighttime net ecosystem CO_2.exchange flux over forest canopy under strong wind in wintertime

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Science China Earth sciences 2005年第Z1期48卷 85-92页

作者： ZHANG Junhui, HAN Shijie, SUN Xiaomin & TANG Fengde institute of Applied Ecology, Chinese Academy of sciences, Shenyang 110016, China institute of geographic sciences and natural resources Research, Chinese Academy of sciences, Beijing 100101, China Department of environment and Life sciences, Liaoning University, Shenyang 110036, China institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China institute of geographic {2. and natural resources Research Chinese Academy of Sciences Beijing 100101 China institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Department of environment and Life sciences Liaoning University Shenyang 110036 China

The mechanism of the negative nighttime net CO2.flux in wintertime and reasonable treatment with it is of great importance in evaluating the carbon metabolism of boreal forest. Results, based on the data obtained with open-path eddy covariance system and CO2.profile measurement system from Nov. 2.02.to Apr. 2.03 and that obtained with five sonic anemometers in Nov. 1999, show that (1) the negative net ecosystem CO2.exchange flux (NEE) always appeared under conditions of strong wind; (2. the pressure fluctuation and horizontal advection flow are dominantly responsible for the negative NEE. Operable upper bound u* filtering method (UU* filtering) was introduced since the difficulties in real-time measuring of pressure fluctuation and horizontal advection fluxes under conditions of strong wind. Nighttime upper u*. threshold for the broad-leaved Korean pine mixed forest of the Changbai Mountains is 0.4 ms-1 and can be applied to the daytime filtering; and (3) the UU* filtering corrected the nighttime 'problem' of negative NEE under strong wind and made the estimates more ecologically reasonable.

关键词： night in wintertime negative NEE eddy-covariance pressure fluctuation UU. filtering

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The application of geographic information technology to coastal geomorphology

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Acta Oceanologica Sinica 2009年第5期28卷 49-57页

作者： GUO Wei LI Shuheng ZHU Dakui School of Human Settlements and Civil Engineering Xi＇an Jiaotong University Xi＇an 710049 China Department of Computer sciences Xi＇an Jiaotong University Xi＇an 710049 China Department of Urban and resources sciences Northwest University Xi＇an 710032 China Faculty of environmental sciences University of Waterloo Waterloo N2L3G1 Canada key laboratory of Coast ＆ Island Development of Ministry of Education Nanjing University Nanjing 210093 China

With the development of modern oceanic observation technologies, coastal survey data have been experiencing a substantial growth. The integration management of the data from different disciplines, different sources and different formats has become a major research field in coastal geomorphology by using geographic Information system （GIS）. This paper puts forward a new methodology framework of GIS techniques in coastal ocean geomorphology, including data acquisition, process, analysis, and representation. It focuses on some major GIS techniques to study the land-ocean interaction mechanism, such as spatial analysis, submarine topography model and three-dimension （3D） visualization, and apply its result to coastal urban planning, harbor site selection and geomorphology {2. about coral reef and islands on the continental shelf. The case studies cover the whole coastal ocean to serve the social community, economical development and diplomatic rights for decision-making all round in the coastal zone. The research shows clearly that the application of coastal multi-source geospatial platform has changed the traditional coastal geomorphology science dramatically from its research scope, fields and methods, however, as made clear in this paper, extracting accurate information from remote sensing data and GIS databases for coastal geomorphological applications is a nontrivial challenge that requires the combined knowledge and skills of information scientists and geomorphologists.

关键词： coastal geomorphology geographic information system (GIS) spatial analysis threedimensional visualization

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Effects of Slopes and Rainfalls on Soil Organic Carbon under Water Erosion in Regions of Hilly Purple Soil

Effects of Slopes and Rainfalls on Soil Organic Carbon under...

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海峡两岸三地环境与资源学术研讨会暨第二届中国环境资源与生态保育学会会员代表大会

作者： HE Binghui~(1,2.,GUO Tian~1,MA Yun~1 1.College of resources and environment,{2. laboratory of Eco-environments in Three Gorges Region (Ministry of Education),Southwest University,Chongqing 400715,China 2.state {2. laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,institute of Water and Soil Conservation,Chinese Academy of sciences and Ministry of Water resources,Yangling 712.00,China

The soil productive forces are mainly affected by soil erosion as soil nutrients and organic carbon are taken *** determine the relationships between the reduction of soil organic carbon and impact factors of soil erosion,the last 17 years' data of slopes and rainfalls in Xiejiawan,Chongqing,China was investigated and *** showed that amount of soil erosion and loss of soil organic carbon caused by water erosion goes up with the increase of gradient,and there was linear correlation between them on the slopes at the range between 8.75%~ 46.63%.And the main effects of rainfall on the loss of organic carbon in purple soil were not embodied in rain intensity,but rainfall parameter had little ***,there was a significant seasonal effect of rain on the loss of organic carbon in purple *** information is provided on the effects of water erosion on soil organic carbon in regions of hilly purple soil.

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Storage and Spatial Variation of Phosphorus in Paddy Soils of China

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Pedosphere 2009年第6期19卷 790-798页

作者： LIN Jin-Shi SHI Xue-Zheng LU Xi-Xi YU Dong-Sheng WANG Hong-Jie ZHAO Yong-Cun SUN Wei-Xia state key {2. of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 2100(78 (China) Department of Geography National University of Singapore 119260 (Singapore) Graduate University of the Chinese Academy of sciences Beijing 100049 (China) College of resources and environment Fujian Agriculture and Forestry University Fuzhou 350002 (China)

Due to the growing concern about the agricultural phosphorus (P) losses pollution, an in-depth understanding of P in paddy soils of China would be helpful in providing a national perspective of the environmental impact of P cycling and fertility on China's farms. In this study, we evaluated the P storage and the P density of paddy soils in China, characterized the spatial variations of P among the subgroups of paddy soils and soil regions in China, and evaluated the P data using GIS-based analysis, which included a newly compiled 1:1 000 000 digital soil map of China, and using 1 490 soil profiles. The available and total P densities of paddy soils were 6.7 and 698.5 g m -3 , respectively. Overall in China, the total P storage within 1 m of paddy soils was estimated to be 330.2.Tg. The P density of paddy soils varied substantially with subgroups due to the different soil water regimes such as groundwater table and soil drainage. The P availability in paddy soils, especially in surface layer, was higher in high temperature and precipitation areas. Further research is needed to examine more anthropogenic impact factors, such as increasing use of chemical fertilizer.

关键词： paddy soil database paddy soil subgroups phosphorus density phosphorus pool

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裂点发育及其对堰塞坝的稳定性影响

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山地学报 2011年第4期29卷 474-482页

作者：张康王兆印刘怀湘余国安清华大学水沙科学与水利水电工程国家重点实验室南京水利科学研究院水文水资源与水利工程科学国家重点实验室中国科学院地理科学与资源研究所

通过野外调查及试验对堰塞坝的稳定和裂点的发育进行研究,发现堰塞坝的稳定性主要取决于泄洪道内阶梯-深潭系统的发育程度Sp和坝体上游洪峰的水流能量p。堰塞坝的保存与溃决情况采用保留的坝高比进行定量描述,对于洪峰流量小于30 m3/s... 详细信息

通过野外调查及试验对堰塞坝的稳定和裂点的发育进行研究,发现堰塞坝的稳定性主要取决于泄洪道内阶梯-深潭系统的发育程度Sp和坝体上游洪峰的水流能量p。堰塞坝的保存与溃决情况采用保留的坝高比进行定量描述,对于洪峰流量小于30 m3/s山区河流,保留坝高比与Sp呈线性相关;洪峰流量大于30 m3/s(<30 000m3/s)时,河道稳定所需的最小河床结构强度Sp随着单宽水流能量p的增加而增大。堰塞坝泄洪道内不发育阶梯-深潭系统或发育程度较低的坝体,Sp值小于稳定河床最小的阻力强度,将会发生下切、溯源冲刷并引起溃坝。保留的堰塞坝在泥沙淤积和水流的长期作用下会形成裂点,对河床下切起到控制作用,降低再次发生滑坡的风险。大型裂点能改变河床演变和河流地貌,连续堰塞坝形成的裂点能长期保存并形成优美的自然景观,创造良好的河流生态环境。

关键词：堰塞坝阶梯-深潭系统裂点河床下切汶川地震

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Parallels plane projection and its geometric features

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Science China Earth sciences 2007年第S1期 176-180页

作者： ZHOU ChengHu1, MA Ting1, YANG Liao2.& QIN Biao3 1 state key {2. of resources and environmental Information system, institute of geographic sciences and natural Re-sources Research, Chinese Academy of sciences, Beijing 100101, China 2.Xinjiang institute of Ecology and Geography, Chinese Academy of sciences, ürümqi 830011, China 3 Department of Applied Mathematics, Xi’an Jiaotong University, Xi’an 710049, China

A new equivalent map projection called the parallels plane projection is proposed in this paper. The transverse axis of the parallels plane projection is the expansion of the equator and its vertical axis equals half the length of the central meridian. On the parallels plane projection, meridians are projected as sine curves and parallels are a series of straight, parallel lines. No distortion of length occurs along the central meridian or on any parallels of this projection. Angular distortion and the proportion of length along meridians (except the central meridian) introduced by the projection transformation increase with increasing longitude and latitude. A potential application of the parallels plane projection is that it can provide an efficient projection transformation for global discrete grid systems.

关键词： map projection parallels plane projection projection distortion

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Contribution of Atmospheric Nitrogen Compounds to N Deposition in a Broadleaf Forest of Southern China

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Pedosphere 2007年第3期17卷 360-365页

作者： HU Zheng-Yi XU Cheng-Kai ZHOU Li-Na SUN Ben-Hua HE Yuan-Qiu ZHOU Jing CAO Zhi-Hong state key {2. of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of SciencesNanjing 210008 （China） College of Forest resources and environment Nanjing Forestry University Nanjing 210007 （China） College of resources and environment Northwest Sci-Tech University of Agriculture and Forestry Yangling 712100（China）

A one-year study in a typical red soil region of southern China was conducted to determine atmospheric nitrogen (N) fluxes of typical N compounds (NH3, NH4-N, NO3-N, and NO2. and contribution of three sources (gas, rainwater, and particles) to N deposition. From July 2.03 to June 2.04, the total atmospheric N deposition was 70.7 kg N ha-1, with dry deposition accounting for 75% of the total deposition. Dry NH3 deposition accounted for 73% of the dry deposition and 55% of the total deposition. Moreover, NO2.contributed 11% of the dry deposition and 8% of the total deposition. Reduced N compounds (NH4+ and NH3) were the predominate contributors, accounting for 66% of the total deposition. Therefore, atmospheric N deposition should be considered when soil acidification and critical loads of atmospheric deposition on soils are estimated.

关键词： atmospheric deposition broadleaf forest nitrogen red soil soil acidification

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Seasonal and annual variation of CO_2.flux above a broad-leaved Korean pine mixed forest

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Science China Earth sciences 2006年第S2期49卷 63-73页

作者： ZHANG Junhui, YU Guirui, HAN Shijie, GUAN Dexin & SUN Xiaomin institute of Applied Ecology, Chinese Academy of sciences, Shenyang 110016, China institute of geographic sciences and natural resources Research, Chinese Academy of sciences, Beijing 100101, China 1. institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China 2. institute of geographic sciences and natural resources Research Chinese Academy of Sciences Beijing 100101 China

Long-term measurement of carbon metabolism of old-growth forests is critical to predict their behaviors and to reduce the uncertainties of carbon accounting under changing climate. Eddy covariance technology was applied to investigate the long-term carbon exchange over a 2.0 year-old Chinese broad-leaved Korean pine mixed forest in the Changbai Mountains (12.°2.’E and 42.2.’N, Jilin Province, P. R. China) since August 2.02. On the data obtained with open-path eddy covariance system and CO2.profile measurement system from Jan. 2.03 to Dec. 2.04, this paper reports (i) annual and seasonal variation of FNEE, FGPP and Re; (ii) regulation of {2.al factors on phase and amplitude of ecosystem CO2.uptake and release Corrections due to storage and friction velocity were applied to the eddy carbon flux. Lal and soil temperature determined the seasonal and annual dynamics of FGPP and RE separately. VPD and air temperature regulated ecosystem photosynthesis at finer scales in growing seasons. Water condition at the root zone exerted a significant influence on ecosystem maintenance carbon metabolism of this forest in winter. The forest was a net sink of atmospheric CO2.and sequestered -449 g C·m-2.during the study period; -2.8 and -171 gC·m-2.for 2.03 and 2.04 respectively. FGPP and FRE over 2.03 and 2.04 were -1332. -12.4 g C·m-2. and 1054, 112. g C·m-2.respectively. This study shows that old-growth forest can be a strong net carbon sink of atmospheric CO2. There was significant seasonal and annual variation in carbon metabolism. In winter, there was weak photosynthesis while the ecosystem emitted CO2. Carbon exchanges were active in spring and fall but contributed little to carbon sequestration on an annual scale. The summer is the most significant season as far as ecosystem carbon balance is concerned. The 90 days of summer contributed 66.9, 68.9% of FGPp, and 60.4, 62.1% of RE of the entire year.

关键词： old-growth forest eddy-covariance carbon metabolism seasonal and annual dynamics

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Study on the Effects of natural Factors on Water Conservation Capacity of Qilian Mountain

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Meteorological and environmental Research 2011年第11期2卷 46-48,63页

作者： GAN Xiao-li 1,SUN De-quan 1,2.3,ZHANG Lin-bo 2.3,JIA Qing-tang 2.3 1.School of Water resources and environment,China University of Geo{2.,Beijing 100083,China 2.key laboratory of state environment Protection Regional Eco-process and Function Assessment,Beijing 100012.China 3.Chinese Research Academy of environmental {2.,Beijing 100012.China

[Objective]The study aimed at analyzing the effects of natural factors on water conservation capacity of Qilian Mountain.[Method] Based on water conservation quantity,elevation data and SPOT-VEGETATION remote sensing data of Qilian Mountain in 2.03,the relationship between water conservation quantity and influencing factors like elevation,slope,aspect and vegetation index varying greatly in the studied area was analyzed quantitatively by means of statistical method,and the effects of natural factors on water conservation capacity of Qilian Mountain were discussed on the basis of water conservation capacity.[Result]In water conservation district of Qilian Mountain,water conservation amount was higher in the region with elevation of 3 600-4 2.0 m or slope of 15°-40°;sunny slope (with slope of 90°-180°) and the area with high vegetation coverage had the strongest water conservation capacity.[Conclusion]The research could provide scientific references for the management of water {2. and vegetation protection in Qilian Mountain.

关键词： Water conservation amount Qilian Mountain Water conservation capacity China

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