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城市生态学长期监测的几个关键问题

生态学报 2024年第14期44卷 5945-5959页

作者：王效科任玉芬张红星孙旭苏芝敏李铣欧阳志云中国科学院生态环境研究中心北京100085 中国科学院大学资源环境学院北京101408 中国科学院北京城市生态系统研究站北京100085

伴随城市人口快速聚集及人类活动加剧,城市生态环境质量及其对人类社会经济发展的支撑能力正在受到严重挑战,城市生态系统及其变化的研究越来越受到重视,国内外涌现出大量城市生态学长期监测工作,但相关监测方法的讨论还很少。在分析城... 详细信息

伴随城市人口快速聚集及人类活动加剧,城市生态环境质量及其对人类社会经济发展的支撑能力正在受到严重挑战,城市生态系统及其变化的研究越来越受到重视,国内外涌现出大量城市生态学长期监测工作,但相关监测方法的讨论还很少。在分析城市生态学长期监测类型和实践经验基础上,从城市面临的环境胁迫和建设管理需求出发,构建了城市生态学长期监测的“胁迫+需求-生态系统响应”总体思路框架;从科学上最基本和社会上最关心的城市生态系统要素、格局和过程着眼,提出城市生态学长期监测的7项内容(土地覆盖与利用、人居环境质量、生物多样性、生物质生产、水文过程、生物地球化学循环和物质代谢);并分析了城市生态学长期监测的4种方法(遥感监测、仪器监测、调查监测、公众科学监测),分析了城市生态学长期监测单元及其空间布局及监测频率。这将为我国城市生态学长期监测工作开展提供方法论基础和实践参考。

关键词：城市生态学长期监测监测内容监测方法监测频率

Relationships Between River Water Quality and Landscape Factors in Haihe River Basin, China: Implications for Environmental Management

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Chinese Geographical Science 2016年第2期26卷 197-207页

作者： XU Huashan ZHENG Hua CHEN Xiaoshu ren yufen OUYANG Zhiyun State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Institute of Resources and Environment Henan Polytechnic University

River water plays a key role in human health, and in social and economic development, and is often affected by both natural factors and human activities. An in-depth understanding of the role of these factors can help in developing an effective catchment management strategy to protect precious water resources. This study analyzed river water quality, patterns of terrestrial and riparian ecosystems, intensity of agricultural activities, industrial structure, and spatial distribution of pollutant emissions in the Haihe River Basin in China for the year of 2010, identifying the variables that have the greatest impact on river water quality. The area percentage of farmland in study area, the percentage of natural vegetation cover in the 1000-m riparian zone, rural population density, industrial Gross Domestic Product(GDP)/km^2, and industrial amino nitrogen emissions were all significantly correlated with river water quality(P rence for developing land use guidelines and for prioritizing management practices to maintain stream water quality in a large river basin.

关键词：水环境管理水环境质量海河流域景观因子污染物排放量国内生产总值植被覆盖率河流水质

Thickness-dependent phase transition and optical behavior of MoS2 films under high pressure

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Nano Research 2018年第2期11卷 855-863页

作者： Xuerui Cheng Yuanyuan Li Jimin Shang Chuansheng Hu yufen ren Miao Liu Zeming Qi School of Physics and Electronic Engineering Zhengzhou University of Light Industry Zhengzhou China National Synchrotron Radiation Laboratory University of Science and Technology of China Hefei China Energy Technologies Area Lawrence Berkeley National Laboratory Berkeley USA

We report the Raman and photoluminescence spectroscopic analysis of layered MoS2 under hydrostatic pressure up to 30 GPa. Unlike previous studies, throughout this work, a special treatment is applied to submerge monolayer, bilayer, multilayer （-200 layers）, and bulk MoS2 samples directly into silicone oil without a supporting substrate in a diamond anvil cell, thereby eliminating possible interference from substrate-film contact. A thickness-dependent trend is observed for the 2Hc-to-2Ha phase transition： The transition pressure increases from 19.0 to 25.6 GPa as the system thickness is reduced from bulk to multilayer MoS2; a further decrease in thickness to the bilayer structure increases the transition pressure to - 36 GPa, as predicted theoretically. This exceeds our measured pressure range, indicating the weakening of interlayer repulsive interactions as the MoS2 film thickness is reduced. Our experiment also reveals a monotonic trend of Raman peak shifting vs. film thickness under applied pressure, suggesting that the Raman vibration modes are more responsive to external pressure in thinner films. The photoluminescence emission peak of the monolayer MoS2 exhibits a blue shift under applied pressure at the rate of 23.8 ***-1. These results show that the structural and optical properties of MoS2 can be effectively modified by applying hydrostatic pressure.

关键词： molybdenum disulfide high pressure Raman spectroscopy photoluminescence diamond anvil cell

Transpiration rates of urban trees, Aesculus chinensis

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Journal of Environmental Sciences 2012年第7期24卷 1278-1287页

作者： Hua Wang Xiaoke Wang Ping Zhao Hua Zheng yufen ren Fuyuan Gao Zhiyun Ouyang State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Institute of Forestry and Pomology Beijing Academy of Agriculture and Forestry SciencesBeijing 100093China South China Institute of Botany Chinese Academy of SciencesGuangzhou 510650China Beijing Teaching Botanical Garden Beijing 100061China

Transpiration patterns of Aesculus chinensis in relation to explanatory variables in the microclimatic, air quality, and biological phenomena categories were measured in Beijing, China using the thermal dissipation method. The highest transpiration rate measured as the sap flux density of the trees took place from 10：00 am to 13：00 pm in the summer and the lowest was found during nighttime in the winter. To sort out co-linearity, principal component analysis and variation and hierarchical partitioning methods were employed in data analyses. The evaporative demand index （EDI） consisting of air temperature, soil temperature, total radiation, vapor pressure deficit, and atmospheric ozone （O3）, explained 68% and 80% of the hourly and daily variations of the tree transpiration, respectively. The independent and joint effects of EDI variables together with a three-variable joint effect exerted the greatest influences on the variance of transpiration rates. The independent effects of leaf area index and atmospheric 03 and their combined effect exhibited minor yet significant influences on tree transpiration rates.

关键词： horse chestnut sap flux density microclimate air pollutants leaf area index

Nitrogen pollution and source identification of urban ecosystem surface water in Beijing

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Frontiers of Environmental Science & Engineering 2014年第1期8卷 106-116页

作者： yufen ren Zhiwei XU Xinyu ZHANG Xiaoke WANG Xiaomin SUN D. J. BALLANTINE Shengzhong WANG State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China College of Urban and Environmental Science Northeast Normal University Changchtm 130024 China National Institute of Water and Atmospheric Research Hamilton 3216 New Zealand

Nitrogen contamination of surface water is a worldwide environmental problem with intensive agricul- ture and high population densities. We assessed the spatial and seasonal variation in concentrations of total nitrogen and different nitrogen species present in surface-water in Beijing, China. Also, chemical （NO3-N/C1-） and isotopic （615Nnitrate） indicators were used to identify nitrate sources. The results showed that, during 2009 and 2010, nitrate nitrogen concentrations ranged from 0.7 to 7.6 mg· L^-1, ammonium nitrogen from 0. I to 3.4 mg· L^-1, and total nitrogen from 2.4 to 17.0mg· L^-1. Inorganic nitrogen accounted for between 60 and 100% of total nitrogen at the ten monitoring sites. Nitrate nitrogen, ammonium nitrogen, and total nitrogen concentrations at the 2 downstream monitoring sites in south-eastern Beijing were significantly higher than those at the other eight upstream monitoring sites （P 〈 0.01）. Examination of seasonal variation showed that there was a significant inverse relationship between nitrate nitrogen concentrations and precipitation, and that nitrate nitrogen concentrations peaked in the dry seasons. The information given by the 15Nnitrate values and nitrate nitrogen concentrations, combined with the NO3-N/C1- ratio distribution, showed that domestic sewage was the major source of nitrate in Beijing. Methods to control and reduce sewage pollution are urgently needed to help manage surface water quality in Beijing.

关键词： nitrogen concentration spatial and seasonalvariation stable nitrogen isotope urban ecosystem source

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侧面紧耦合泵浦微型激光器研究

红外与激光工程 2013年第5期42卷 1174-1178页

作者：商继敏任宇芬郑州轻工业学院技术物理系河南郑州450002

利用解析法分析了激光二极管(LD)侧面紧耦合泵浦固体激光器中泵浦光强分布特点,其增益分布与发光单元发光面处的束腰半径、激光二极管等间距环绕个数、泵浦源与晶体表面的距离、晶体棒半径和工作物质的吸收系数有关,通过调整泵浦参数可... 详细信息

利用解析法分析了激光二极管(LD)侧面紧耦合泵浦固体激光器中泵浦光强分布特点,其增益分布与发光单元发光面处的束腰半径、激光二极管等间距环绕个数、泵浦源与晶体表面的距离、晶体棒半径和工作物质的吸收系数有关,通过调整泵浦参数可以实现中心强边缘弱的泵浦光分布。采用LD紧贴于Nd:YAG的紧耦合双侧面对称泵浦技术,对侧面紧耦合泵浦微型激光器进行了相关研究,实验上实现了激光二极管泵浦固体激光器(DPL)的微型化。

关键词：微型激光器泵浦光分布紧耦合泵浦激光二极管侧面泵浦固体激光器

In situ Crystallization of Ionic Liquids [EMIM][NO3] from Its Supercooled Liquid under Extreme Conditions

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In situ Crystallization of Ionic Liquids [EMIM][NO3] from It...

替代面法和推算法在淅川库区氨氮干沉降评估中的适用性分析

第十八届中国高压科学学术会议

作者：吴杰 Junyu Li yufen ren Xiang Zhu Haining Li Kun Yang Zheng Wang Lei Su The High Pressure Research Center of Science and Technology Zhengzhou University of Light Industry Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences

[EMIM][NO]is a halogen-free ionic liquid and relatively hydrolysis-stable *** could be an interesting alternative for industrial application due to the fact that it avoids the liberation of toxic and corrosive HF into the *** this work,we are concerned with the phase transitions of[EMIM][NO]by using Raman scattering as a function of pressure or *** significant changes in spectra show that[EMIM][NO3]undergoes a liquid to solid phase transition at 0.9

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环境科学学报 2022年第12期42卷 423-431页

作者：陈晓舒赵同谦任玉芬肖春艳贺玉晓陈飞宏张清淼河南理工大学资源环境学院焦作454000 北京京津冀区域生态环境变化与综合治理国家野外科学观测研究站北京100085

农业源氨氮沉降是水库型水源地水体收到的重要的外源氮之一,其沉降量评估与来源识别是水体氮污染防控的重要依据.替代面法和推算法是大气氮素干沉降监测的两种常用方法.采用替代面法和推算法,于2019年9月—2020年8月对淅川库区周边设置... 详细信息

农业源氨氮沉降是水库型水源地水体收到的重要的外源氮之一,其沉降量评估与来源识别是水体氮污染防控的重要依据.替代面法和推算法是大气氮素干沉降监测的两种常用方法.采用替代面法和推算法,于2019年9月—2020年8月对淅川库区周边设置的5个大气监测点进行干沉降样品采集,测定了样品中氨氮浓度及其氮同位素,探讨了2种监测方法在氨氮干沉降通量估算及氨氮来源解析中的适用性.结果表明:替代面法获得的氨氮干沉降通量为推算法的1.4~2.1倍,2种监测方法获得的氨氮干沉降通量在时空变化趋势上具有一致性;推算法获得的δ^(15)N-NH_(4)^(+)较替代面法偏负,季均相差为11.1‰,时空差异显著.替代面法在获得淅川库区氨氮干沉降通量方面具有优势,受氨氮分馏影响,直接获得的δ^(15)N-NH_(4)^(+)值较初始源δ^(15)N-NH_(3)值存在较大偏差,影响溯源结果的准确性;推算法能够分别获得不同氨氮形态干沉降中的δ^(15)N-NH_(4)^(+)值,适用于氨氮干沉降来源分析,但易造成氨氮干沉降通量偏低;综合利用2种监测方法能够提高同位素溯源结果的准确性.

关键词：干沉降氨氮推算法替代面法水库型水源地农业

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城市生态学自然模拟实验研究进展

生态学报 2023年第5期43卷 1763-1774页

作者：王效科赵露任玉芬张红星苏芝敏孙旭欧阳志云中国科学院生态环境研究中心城市与区域生态国家重点实验室北京100085 中国科学院大学北京100049 中国科学院北京城市生态系统研究站北京100085

自然模拟实验,通过适当控制影响因素研究自然状态下生态系统变化,已经越来越受到生态学家的欢迎。新兴的快速发展的城市生态学越来越多的采用自然模拟实验方法。研究从城市生态学的实验设计方法(如人工梯度、自然梯度和城市建设实验)、... 详细信息

自然模拟实验,通过适当控制影响因素研究自然状态下生态系统变化,已经越来越受到生态学家的欢迎。新兴的快速发展的城市生态学越来越多的采用自然模拟实验方法。研究从城市生态学的实验设计方法(如人工梯度、自然梯度和城市建设实验)、环境因子(如空气污染、热岛、灯光和地表硬化)生态效应和生态系统(如社区、绿地、绿化屋顶和集水区)响应等方面,分析了国内外大量城市生态学自然模拟实验的研究案例,并总结了城市生态学自然模拟实验的特点,指出了城市生态学模拟实验应该考虑的主要问题,并提出未来主要发展方向:(1)多种环境因子复合影响模拟实验研究,(2)生态系统结构和功能响应模拟实验研究,(3)近自然的长期模拟实验研究,(4)大范围的联网模拟实验研究和(5)面向城市生态恢复和建设的模拟实验研究。希望研究能够为推进我国城市生态学的实验研究起到抛砖引玉作用。

关键词：自然模拟实验城市生态学实验设计方法城市环境因子城市生态系统