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A meta-analysis of the canopy light extinction coefficient in terrestrial ecosystems

Frontiers of Earth Science 2014年第4期8卷 599-609页

作者： Liangxia ZHANG Zhongmin HU Jiangwen FAN Decheng ZHOU fengpei tang Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100039 China College of Urban and Environmental Sciences Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Beijing 100871 China China University of Mining & Technology Beijing 100083 China

The canopy light extinction coefficient （K） is a key factor in affecting ecosystem carbon, water, and energy processes. However, K is assumed as a constant in most biogeochemical models owing to lack of in-site measurements at diverse terrestrial ecosystems. In this study, by compiling data of K measured at 88 terrestrial ecosystems, we investigated the spatiotemporal variations of this index across main ecosystem types, including grassland, cropland, shrubland, broadleaf forest, and needleleaf forest. Our results indicated that the average K of all biome types during whole growing season was 0.56. However, this value in the peak growing season was 0.49, indicating a certain degree of seasonal variation. In addition, large variations in K exist within and among the plant functional types. Cropland had the highest value of K （0.62）, followed by broadleaf forest （0.59）, shrubland （0.56）, grassland （0.50）, and needleleaf forest （0.45）. No significant spatial correlation was found between K and the major environmental factors, i.e., mean annual precipitation, mean annual temperature, and leaf area index （LAI）. Intra-annually, significant negative correlations between K and seasonal changes in LAI were found in the natural {K=2/π[cosαcosθsina^-1（tanθtanα）＋（1＋cos^2a-cos^2θ^1/2）],a＋θ〉π/2 K=cosαcosθ,α＋θ≤π/2 k K is usually calculated with the Beer Lambert Law （Monsi and Sakei, 1953）：K = - In （Ii/Io） cosθ/（LAIΩ）,（2）ecosystems. In cropland, however, the temporal relation- ship was site-specific. The ecosystem type specific values of K and its temporal relationship with LAI observed in this study may contribute to improved modeling of global biogeochemical cycles.

关键词： canopy light extinction coefficient ecologicalmodeling biogeochemical model forest grassland cropland leaf area index

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Preliminary Study on Mercury Emission from Typical Underground Coal Fire Zone in China

Preliminary Study on Mercury Emission from Typical Undergrou...

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Environmental Pollution and Public Health(EPPH 2012)

作者： Yanci Liang Shuquan Zhu Handong Liang Zhiyong Wang fengpei tang School of Chemical&Environmental Engineering China University of Mining and Technology Beijing State Key Laboratory of Coal Resources and Safe Mining College of Geoscience and Surveying Engineering China University of Mining and Technology Beijing

To study potential release of environmental hazardous species from underground coal fire, in situ headspace air measurements were applied over one hundred natural vent in a mining area in central Inner Mongolia （central coordinates: 39° 30′44″N/106°37′05″E , altitude:1246.82m, area: 9500m2） by portable mercury vapor analyzer （RA-915+, Lumex Ltd., St. Petersburg, Russia）. The results show the release of zero-valent mercury from each natural vent of underground coal fire, with an average mercury concentration 323.52ng/m3 （n=102）, indicating a possible universal mercury emission from underground coal fire in China. This finding suggests the underground coal fire could be an unnegligible source of global mercury emission inventory. The subsequent potential environmental and public health impact should be taken into consideration in further policy making of massive coal mining.

关键词： mercury emission underground coal fire environmental catastrophe public health threat Inner Mongolia

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区域尺度生态系统水分利用效率的时空变异特征研究进展

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地球科学进展 2014年第6期29卷 691-699页

作者：张良侠胡中民樊江文邵全琴唐风沛中国科学院地理科学与资源研究所北京100101 中国科学院大学北京100049 中国矿业大学北京100083

水分利用效率(WUE)是深入理解生态系统水—碳循环耦合关系的重要指标,揭示区域尺度生态系统WUE的时空变异特征及其控制机制,有助于评价和预测全球变化对生态系统水、碳过程的影响。综述了目前区域尺度生态系统WUE的研究进展,结果表明:... 详细信息

水分利用效率(WUE)是深入理解生态系统水—碳循环耦合关系的重要指标,揭示区域尺度生态系统WUE的时空变异特征及其控制机制,有助于评价和预测全球变化对生态系统水、碳过程的影响。综述了目前区域尺度生态系统WUE的研究进展,结果表明:①目前关于生态系统WUE影响因素的研究多基于站点尺度,区域尺度的研究相对缺乏;②关于不同生态系统WUE的大小及时间变化特征已有较明确的结论,而基于生态模型方法获取的生态系统WUE的空间分布格局尚需进一步验证;③已有研究表明气候变化和土地利用/覆被变化(LUCC)均会显著改变生态系统生产力或蒸散,然而,较少研究关注两者导致的生态系统WUE的改变。因此,区域尺度生态系统WUE时空变异的控制因子及其对气候变化和LUCC的响应可能是未来全球变化研究的热点问题之一。

关键词：区域尺度水分利用效率(WUE) 气候变化土地利用覆被变化(LUCC)

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Drilling load modeling and validation based on the filling rate of auger flute in planetary sampling

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Chinese Journal of Aeronautics 2017年第1期30卷 434-446页

作者： Quan Qiquan tang Junyue Yuan fengpei Jiang Shengyuan Deng Zongquan State Key Laboratory of Robotics and System Harbin Institute of Technology

Some type of penetration into a subsurface is required in planetary sampling. Drilling and coring, due to its efficient penetrating and cuttings removal characteristics, has been widely applied in previous sampling missions. Given the complicated mechanical properties of a planetary regolith, suitable drilling parameters should be matched with different drilling formations ***, drilling faults caused by overloads could easily happen. Hence, it is necessary to establish a drilling load model, which is able to reveal the relationships among drilling loads, an auger＇s structural parameters, soil＇s mechanical properties, and relevant drilling parameters. A concept for the filling rate of auger flute（FRAF） is proposed to describe drilling conditions. If the FRAF index under one group of drilling parameters is less than 1, this means that the auger flute currently removes cuttings smoothly. Otherwise, the auger will be choked with compressed cuttings. In drilling operations, the drilling loads on the auger mainly come from the conveyance action, while the drilling loads on the drill bit primarily come from the cutting action. Experiments in one typical lunar regolith simulant indicate that the estimated drilling loads based on the FRAF coincide with the test results quite well. Based on this drilling load model, drilling parameters have been optimized.

关键词： Coring Drilling load Filling rate of auger fluteLunar regolith simulant Planetary drilling

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A benzothiazole-based ratiometric fluorescent probe with large Stokes shifts for quantitative profiling of sulfite in real samples and living cells

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Green Chemical Engineering 2023年第4期4卷 427-432页

作者： fengpei Qi Xiuxiu Yue Yitong Yang Qin Liang Ruiren tang Xiangzhi Song College of Chemistry&Chemical Engineering Central South UniversityChangsha410083China College of Materials&Chemical Engineering Hunan City UniversityYiyang413000China

Rapid,selective,and quantitative profiling of SO_(3)^(2-)is a prerequisite for investigating its effect on different physiopathological *** address this challenge,our team prepared a ratiometric fluorescent probe HBTCS,based on 4-(benzothiazol-2-yl)-3-hydroxybenzaldehyde for specific detection of SO_(3)^(2-)under a singlewavelength *** solution of probe HBTC-S itself exhibited orange fluorescence(λ_(em)=614 nm),and became green fluorescent(λ_(em)=471 nm)after the addition of SO_(3)^(2-).The vitro experiments suggested that the probe displayed high sensitivity,excellent selectivity,and a low detection limit(0.15μM).Moreover,probe HBTC-S was successfully applied for qualitative and quantitative monitoring of SO_(3)^(2-)in realistic samples and living HeLa cells in a ratiometric manner.

关键词： Ratiometric Fluorescent probe Sulfite(SO_(3)^(2-)) Single-wavelength excitation Living imaging

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江苏省CO_2煤层地质封存条件与潜力评价

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高校地质学报 2012年第2期18卷 203-214页

作者：姚素平汤中一谭丽华裴文明表生地球化学教育部重点实验室南京大学地球科学与工程学院南京210093

根据江苏省石炭—二叠纪煤系的分布、煤炭资源量和煤层的储集条件等煤封存CO2地质条件的综合研究,分别对苏南煤田、徐州煤田、丰沛煤田煤层封存CO2的潜力进行了初步评估,认为该区CO2煤层封存具有一定的潜力和前景。评估结果表明江苏省... 详细信息

根据江苏省石炭—二叠纪煤系的分布、煤炭资源量和煤层的储集条件等煤封存CO2地质条件的综合研究,分别对苏南煤田、徐州煤田、丰沛煤田煤层封存CO2的潜力进行了初步评估,认为该区CO2煤层封存具有一定的潜力和前景。评估结果表明江苏省煤层可存储CO2总量超过3×108t,其中苏南含煤区可存储CO2容量为8.1×107t,徐州煤矿区可存储容量近1.5×108t,丰沛煤矿区为8.7×107t。并对各典型含煤区块CO2煤封存前景进行分类:适合存储区(A类)、较适合存储区(B类)和较差存储区(C类)。

关键词： CO2-ECBM 封存条件潜力评价江苏省

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