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Endolithic fungi:A possible killer for the mass extinction of Cretaceous dinosaurs

Science China Earth Sciences 2008年第6期51卷 801-807页

作者： GONG YiMing1,2, XU Ran1 & HU Bi2 1 Key Laboratory of Biogeology and environmental Geology of Ministry of Education, State Key Laboratory of Geological Processes and Mineral resources, China University of Geosciences, Wuhan 430074, China 2 institute of resources and environment Key Laboratory of Biogenic Traces & Sedimentary Minerals of Henan Province, Henan Polytechnic University, Jiaozuo 454003, China Key Laboratory of Biogeology and environmental Geology of Ministry of Education State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan China institute of resources and environment Key Laboratory of Biogenic Traces & Sedimentary Minerals of Henan Province Henan Polytechnic University Jiaozuo China

Mycelium-like structures found under ESEM within radial sections of fragmental dinosaur eggshells would be the endolithic fungi coexistent with dinosaur eggs in the upper part of the Late Cretaceous Hugang Formation from the Wenjiaping section of Wenxian, Danjiangkou, northwestern Hubei, Central China. The endolithic fungi selectively occurred in the bad biomineral zone within the columnar layer of the eggshells, where the crowded endolithic fungi penetrated the columnar layer at near-vertical or near-horizontal angles. The endolithic fungi are needle-like, ribbon-like and silk-like, and 5-18 μm long, 0.3-0.5 μm wide at their base, with pointed tip, and are unbranched. The hyphae are mainly composed of oxygen, carbon and calcium, and are with minor sodium, potassium, chlorine and sulfur. The en-dolithic fungi and host have the same characters in lithification, fracture and main chemical composi-tion. We suggested that the episode endolithic fungi invading dinosaur eggs may have taken place in the interval between after formation of dinosaur eggshells and before their petrifaction and that dino-saur eggs invaded by endolithic fungi would not be normally incubated or would only be incubated into venerable and pathologic baby dinosaurs to be easily to aborted and contributed to the mass extinction of the dinosaurs at the end of Cretaceous.

关键词： endolithic fungi dinosaur eggs mass extinction Cretaceous

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Nitrogen and oxygen isotope budget balance in tropospheric N_2O

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Chinese Science Bulletin 1999年第S2期44卷 99-100页

作者： XU Wenbin~(1,2) and HONG Yetang~1 1. State Key Laboratory of environmental Geochemistry, institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China 2. institute of environment and resources Chemistry, Zhejiang University, Hangzhou 310027, China State Key Laboratory of environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China institute of environment and resources Chemistry Zhejiang University Hangzhou 310027 China

THK N2O is an important greenhouse gas. In the steady state the stable isotopic composition of nitrogenand oxygen in tropospheric N2O is balanced by isotopically light N2O emitted from soils and oceans andisotopically heavy N2O as return flux from the stratosphere. However, no such balance was reached incalculations given by Kim and Craig. This serious discrepancy lied in the fact that only soil and oceanic sources were considered in Kim and Craig’s calculation and N2O emission from tropical forest soil wastaken as the global soil contribution. Progress since the 1990s in identifying additional sources of atmospheric N2O as well as in the estimation from various types of soil allows us to make more realistic assessment of nitrogen and oxygen isotope balance budgets in tropospheric N2O. In this note, modification willbe proposed of atmospheric N2O nitrogen and oxygen isotope budgets to Kim and Craig’s calculation. The static balance of nitrogen and oxygen isotopes in tropospheric N2O is expressed

关键词： N2O nitrogen stable isotope oxygen stable isotope budget balance troposphere.

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The potential effect of variations in climate and agricultural practice on N_2O emissions (Ⅱ)——Variations in agricultural practice

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Chinese Science Bulletin 1999年第S2期44卷 97-99页

作者： XU Wenbin~(1,2), HONG Yetang~1, CHEN Xuhui~3, LI Changsheng~4, LIN Qinghua~1 and WANG Yu~1, 1. State Key Laboratory of environmental Geochemistry, institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China 2. institute of environment and resources Chemistry, Zhejiang University, Hangzhou 310027, China 3. Soil and Fertilizer institute, Guizhou Academy of Agricultural Sciences, Guiyang 550013, China 4. institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, USA State Key Laboratory of environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China institute of environment and resources Chemistry Zhejiang University Hangzhou 310027 China Soil and Fertilizer institute Guizhou Academy of Agricultural Sciences Guiyang 550013 China institute for the Study of Earth Oceans and Space University of New Hampshire Durham NH United States

WE expanded Decomposition-Denitrification （DNDC）modeling study to systematically assess the potential effect of farming practice on N2O emission by choosing a corn-rape rotation and a soybean-winterwheat rotation field in Guizhou Province, westsouthern China, asN2O emission from subtropical agricultural soil study plots. These sensitivity studies address questions relevant to issue of how change in fanning practice might be used to mitigate emissions. Manure additions had the most pronounced impact on N2O emissions of farming practice simulatedand the influence of manure addition was nonlinear （fig. 1）. This result is consistent with previous studies for an Iowa corn field. The addition of manure remarkably elevates the level of organic carbon, enhances soil nitrogen mineralization, and increases the efficiency of N2O production. Simulated results alsoshowed that the influence of manure additions on N2O emission from soybean-winter wheat field had

关键词： N2O emission farming practice potential effect agricultural soil.

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The influence of temperature on diurnal and seasonal variations of N_2O flux from agricultural soilis in Guizhou

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Chinese Science Bulletin 1999年第S2期44卷 101-102页

作者： XU Wenbin~(1,2), HONG Yetang~1, CHEN Xuhui~3, QIN Song~3 and JIANG Taiming~3 1. State Key Laboratory of environmental Geochemistry, institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China 2. institute of environment and resources Chemistry, Zhejiang University, Hangzhou 310027, China 3. Soil and Fertilizer institute, Guizhou Academy of Agricultural Sciences, Guiyang 550013, China

AGRICULTURAL soils are the major anthropogenic source of N2O, and temperature is one of the importantenvironmental factors controlling production and emission of N2O from soil. This work focuses on the influence of temperature on diurnal and seasonal variations of N2O flux from subtropical agricultural *** was done by seasonal measuring N2O flux and soil temperature at a corn-rape rotation, a soybeanwinter wheat rotation and a fallow field （106°66’E, 26°50’N, 1140 m a.s.1.）, at Soil and Fertilizer institute, Guizhou Academy of Agricultural Sciences. Available nitrogen content of above three fields wasapproximately 0.71%, organic matter content 10.6-12.0 g/kg, clay （2 μm） content 25.6%-30.0%, and pH was about 7.5 throughout the whole experiment. Measuring period was between 20 Mar.

关键词： N2O flux temperature diurnal variation seasonal variation agricultural soil.

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波动方程震源组合模拟定量研究

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石油地球物理勘探 2011年第4期46卷 538-544,667+493页

作者：汪仁富徐峰刘福烈谢洁浙江大学地质与地球物理研究所浙江杭州310027 西南石油大学资源与环境学院四川成都610500 胜利油田桩西采油厂山东东营257237

震源组合已在中国西部复杂山前勘探中取得了较好的应用效果,但对震源组合的波动力学机理还缺乏深入的研究。本文通过有限差分波动方程模拟技术,定量分析不同震源组合情况下震源附近的能量分布,建立针对目标地层的入射能量评判函数;对非... 详细信息

震源组合已在中国西部复杂山前勘探中取得了较好的应用效果,但对震源组合的波动力学机理还缺乏深入的研究。本文通过有限差分波动方程模拟技术,定量分析不同震源组合情况下震源附近的能量分布,建立针对目标地层的入射能量评判函数;对非时延震源组合的能量分布作了详细讨论;并对不同震源组合单炮记录的抗噪能力进行对比分析。试验表明,利用有限差分波动方程求解的震源组合在入射能量较大时单炮记录的信噪比高,组合效果好,并且能够利用入射能量评判函数对震源组合效果做出定量评判。该方法可为定量评价和优化震源组合效果提供一种可行的技术手段。

关键词：波动方程震源组合模拟定入射能量模拟技术有限差分能量分布

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A New Analytical Method of the Water resources Allocation in China

A New Analytical Method of the Water Resources Allocation in...

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2014年环境污染与大众健康学术会议

作者： Yanqi ZHAO1 2 3 Changming LIU1 Ying YANG2 Hongxing ZHENG1 1institute of Geographic Sciences and Natural resources Research CAS Beijing 100101 China 2institute of resources & environment Henan Polytechnic University(HPU) Jiaozuo Henan 45400 China 3Graduate University of Chinese Academy of Sciences Beijing 100101 China

The paper introduces the Gini coefficient of economics as a new method of analyzing the inter-provincial allocation of water resources in *** calculated the Gini coefficient for selected indices based upon the statistical data for each province from 1997 to 2008,respectively taking the population,GDP and the cultivated area as the basic matching ***,we proposed two novel indexes:the Dependence Coefficient to weigh the degree of reliance on the surface water or groundwater for the separated regions and the Burden Coefficient of water use to judge the efficiency and the level of fairness of water consumption by different *** results show that the allocation of water resources calculated per capita,per unit GDP and per unit area of arable land is very *** particular,some provinces located north of the Yangtze River lack water resources and strongly depend on the *** water efficiency is there lower than in other parts of ***,in order to alleviate the water stress in the northern provinces of the country,an improvement of the technological level of water resources exploitation and utilization and also the restructuring of the economic activity are necessary.

关键词： water resources allocation Gini coefficient Dependence Coefficient Burden Coefficient

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贵州喀斯特山区石漠化治理过程中土壤质量特性研究

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水土保持学报 2004年第6期18卷 112-115页

作者：罗海波宋光煜何腾兵刘丛强刘方刘元生钱晓刚西南农业大学资源环境学院重庆北碚400716 贵州大学环境与资源研究所贵州贵阳550025 中国科学院地球化学研究所贵州贵阳550002

通过定位、半定位观测,对贵州喀斯特山区石漠化治理过程中土壤质量特性进行研究,探讨贵州喀斯特山区生态恢复过程中土壤特性以及土壤肥力变化规律。试验结果表明:喀斯特地区石漠化综合治理对土壤物理化学性质的影响较为明显,表现为表层... 详细信息

通过定位、半定位观测,对贵州喀斯特山区石漠化治理过程中土壤质量特性进行研究,探讨贵州喀斯特山区生态恢复过程中土壤特性以及土壤肥力变化规律。试验结果表明:喀斯特地区石漠化综合治理对土壤物理化学性质的影响较为明显,表现为表层土壤有机质增加,土壤容重降低,孔隙度增加,土壤理化性质改善,保水保肥能力和通道性增加;同时,土壤微生物数量增加,土壤微生物数量增加程度表现为细菌>放线菌>真菌,土壤肥力改善,生产力逐渐提高。

关键词：贵州喀斯特山区石漠化治理土壤质量特性

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基于集对分析的喀斯特生态景观退化诊断研究--以毕节地区为例

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水土保持研究 2011年第4期18卷 11-15页

作者：邵技新张凤太苏维词曹欢贵州师范学院地理与旅游学院贵阳550018 贵州师范学院资源环境与灾害研究所贵阳550018 南京大学地理与海洋学院南京210093 贵州省科学院山地资源研究所贵阳550001

从生态景观的结构退化、功能退化和环境污染等3个方面选择了21个评价指标,组成喀斯特地区生态景观退化评价诊断指标体系,并制定诊断评价标准,借助集对分析方法,以毕节地区为例进行分析,得出毕节地区的2003-2006年生态景观分别处于中度... 详细信息

从生态景观的结构退化、功能退化和环境污染等3个方面选择了21个评价指标,组成喀斯特地区生态景观退化评价诊断指标体系,并制定诊断评价标准,借助集对分析方法,以毕节地区为例进行分析,得出毕节地区的2003-2006年生态景观分别处于中度退化、中度退化、轻退化、中度退化4个阶段。生态景观退化处于波动状态,但整体趋势趋于良好。评价结果与已有喀斯特生态系统健康研究相互印证,研究确定的喀斯特生态景观退化诊断指标体系和诊断标准以及诊断方法具有一定科学价值,对指导喀斯特地区的生态景观优化、设计和修复具有一定参考价值。

关键词：集对分析喀斯特生态景观退化诊断

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外源稀土对土壤微生物特征的影响及时间效应

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中国稀土学报 2003年第5期21卷 589-593页

作者：周峰陈浮曹建华濮励杰彭补拙南京大学城市与资源学系水土环境模拟实验室江苏南京210093 南京农业大学农业资源与生态环境研究所江苏南京210095

采用微生物生物量、cmic corg、呼吸速率、代谢熵qCO2及BIOLOG等方法分析稀土对土壤微生物活性及群落结构的影响和时间效应。结果表明,低浓度稀土进入土壤的早期阶段对土壤微生物具有刺激作用,但随时间的推移逐渐不显著。高浓度稀土对... 详细信息

采用微生物生物量、cmic corg、呼吸速率、代谢熵qCO2及BIOLOG等方法分析稀土对土壤微生物活性及群落结构的影响和时间效应。结果表明,低浓度稀土进入土壤的早期阶段对土壤微生物具有刺激作用,但随时间的推移逐渐不显著。高浓度稀土对土壤微生物具有抑制作用,随时间的延长有减少的趋势。BIOLOG分析显示,稀土施用之后,土壤微生物对碳源的消耗量增加,速度加快,群落结构发生了改变且具有长期性。

关键词：农业微生物学微生物量呼吸强度群落结构水稻土稀土

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A Study On The Treatment Of Wastewater From Printed Circuit Boards Wet Process

A Study On The Treatment Of Wastewater From Printed Circuit ...

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2011 IEEE International Conference on Waste Recycling,Ecology and environment(ICWREE 2011)

作者： Caibin WU1*, Luyan MIN1, Jie LIU1, Cuiping YAN2 1 School of Civil Engineering and Architecture, East China Jiao Tong University, Ganzhou, Nanchang, Jiangxi, China 2 institute of environment and resources, Southwest University of Science and Technology, Mianyang, Sichuan, China

The wet process of handling the wasted printed circuit boards can make a large quantity of wastewater. In order to recycle the wastewater, coagulation method is employed using polyaluminum chloride (PAC) and polyferric sulphate (PFS) as coagulants and polyacrylamide (PAM) as aid coagulant. This paper studies the effects of the removal of turbidity and CODcr considering the factors of detention time, pH, G value, coagulants dosage and aid coagulant on coagulation. The results show that over 99% and 80% of turbidity and CODcr can be respectively removed when coagulant dose of PAC and PFS is 75 mg/L and 150 mg/L under pH between 7.0 and 8.5;over 98% and 90% of turbidity and CODcr can be respectively re- moved when the reaction speed is in the range of 50 to 100 r/min, namely G value is of 8.77 22.41 s-1,and dosing aid coagulant, PAM, can reduce the PAC or PFS dosage and accelerate setting velocity. The optimal operation conditions are 10mg/L PAC, 0.5mg/L PAM, and stirring velocity of 50r/min and G value of 8.77s-1, and 99.39% of turbidity and 88% of CODcr can be removed respectively;the effluent can meet the requirement of the reuse standard with turbidity of 1.1 NTU and CODcr of 41.74mg/L.

关键词： wasted printed circuit boards(PCBs) wastewater coagulation turbidity CODcr

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