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North-south vegetation transition in the eastern Qinling-Daba Mountains

Journal of geographical Sciences 2021年第3期31卷 350-368页

作者： zhang Xinghang zhang Baiping WANG Jing {2. Fuqin ZHAO Chao YAO Yonghui State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China University of chinese academy of Sciences Beijing 100049China Ministry of Civil Affairs of the People's Republic of china Beijing 100007China

The Qinling-Daba Mountains are the main body of china’s North-South Transitional *** of the north-south gradual variation of vegetation components is significant for understanding the structural diversity and complexity of this transitional *** this study,based on survey data of plant communities,the eastern Qinling-Daba Mountains is divided into four geographic units:the north flank of eastern Qinling Mts.,south flank of eastern Qinling Mts.,north flank of eastern Daba *** south flank of eastern Daba *** also explore division of regional climate according to areal differentiation of plant-species,community structure and species-richness,*** results show that,(1)at plant-species level,there are mainly northern plants in north flank of eastern Qinling *** evergreen species and fewer northern plants in south flank of eastern Qinling Mts.;there are mainly southern plants in eastern Daba Mts.(2.At community structure level,there are 4 formations({2.northern formations and 1 widespread formation)in north flank of eastern Qinling,6 formations({2.northern formations,1 southern formation,and 2.widespread formations)in south flank of eastern Qinling,4 formations(2.southern formations and 2.widespread formations)in north flank of eastern Daba Mts.,and {2.formations({2.southern formations)in south flank of eastern Daba *** terms of the numbers and properties of formations,there is a mixture of northern and southern formations only in the south flank of eastern Qinling Mts.({2.At species-richness level,the diversity of families,genera and species decreased with increasing latitude,but the mixing of northern plants and the southern plants began to occur in south flank of eastern Qinling *** means that the south flank of the eastern Qinling *** more suitably as the dividing line between china’s warm temperate and subtropical zones.

关键词： china’s north-south transitional zone eastern Qinling-Daba Mountains north-south transect vegetation series climate north-south dividing line

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Granier原始公式测算107杨树干液流通量密度的误差及校正公式

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林业科学 2021年第3期57卷 161-169页

作者：马长明张含含韩煜孟庆星张劲松马玉洁河北农业大学林学院保定071000 保定市自然资源和规划局保定071000 中国林业科学研究院林业研究所北京100091

【目的】验证Granier原始公式对测算107速生杨树干液流通量密度时的适用性,为精准计算林木蒸腾量提供依据。【方法】以107速生杨为对象,基于热扩散树干液流测定技术,采用离体茎段式称重法和整树容器称重法实测液流通量密度,以验证Granie... 详细信息

【目的】验证Granier原始公式对测算107速生杨树干液流通量密度时的适用性,为精准计算林木蒸腾量提供依据。【方法】以107速生杨为对象,基于热扩散树干液流测定技术,采用离体茎段式称重法和整树容器称重法实测液流通量密度,以验证Granier原始公式的适用性,并通过建立实测液流通量密度与热扩散法测定的树干液流温差系数(K值)的统计关系,形成校正公式。【结果】和整树容器称重法和室内茎段称重法的实测值相比,Granier原始公式计算的液流通量密度存在严重低估,误差率分别达-71.5%和-74.3.。基于整树容器称重法和室内茎段称重法的实测值而建立的校正公式分别为Fd(液流通量密度,cm3.cm^(-2.s^(-1))=0.0108K^(0.5666)(R^(2.=0.812.)和Fd=0.01917K^(0.952.)(R^(2.=0.9403.。经6月2.0}、2.日数据验证,在以林木自然生长条件下的野外整树容器称重法实测值为基准时,Granier原始公式的计算值低估68.90%,而整树容器称重法拟合的校正公式计算值仅低估2.95%,离体茎段称重法拟合的校正公式计算值低估15.75%。【结论】Granier原始公式在计算107速生杨树干液流通量密度值时存在严重低估,会造成很大误差,但校正公式可反映液流通量密度与K值的关系,能准确表达出真实的液流量。因此,采用基于整树容器称重法校正的Granier公式所计算的107速生杨树干液流通量密度具有较高精度。

关键词：热扩散 107杨离体茎段称重法整树容器称重法校正公式

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Study of the continuum removal method for the Moon Mineralogy Mapper(M^3. and its application to Mare Humorum and Mare Nubium

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research in Astronomy and Astrophysics 2016年第7期16卷 133-142页

作者： Xun-yu zhang Zi-yuan Ouyang Xiao-Meng zhang yuan Chen Xiao Tang Ao-Ao Xu Ze-Sheng Tang yun-Zhao Wu Space Science institute Macao University of Science and Technology Macao 00853 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China School of geographic and Oceanographic Sciences Nanjing University Nanjing 210023 China Key Laboratory of Planetary Sciences Chinese Academy of Sciences Nanjing 210008 China

The absorption band center of visible and near infrared reflectance spectra is a key spectral parameter for lunar mineralogical studies, especially for the mafic minerals（olivine and pyroxene） of mare basalts, which have two obvious absorption bands at 1000 nm（Band I） and 2.00 nm（Band II）. Removal of the continuum from spectra, which was developed by Clark and Roush and used to isolate the particular absorption feature, is necessary to estimate this parameter. The Moon Mineralogy Mapper（M3. data are widely used for lunar mineral identification. However, M3.data show a residual thermal effect, which interferes with the continuum removal, and systematic differences exist among optical data taken during different optical periods. This study investigated a suitable continuum removal method and compared the difference between two sets of M3.data taken during different optical periods, Optical Period 1B（OP1B）and Optical Period 2.（OP2.）. Two programs for continuum removal are reported in this paper. Generally,a program respectively constructs two straight lines across Band I and Band II to remove the continuum,which is recommended for locating band centers, because it can find the same Band I center with different right endpoints. The optimal right endpoint for continuum removal is mainly dominated by two optical period data at approximately 2.80 and 2.60 nm for OP1 B and OP2.A data, respectively. The band center values derived from OP1 B data are smaller than those derived from OP2.A data in Band I but larger in Band II, especially for the spectra using longer right endpoints（〉2.00 nm）. This may be due to the spectral slopes of OP1 B data being steeper than those of OP2.A data in Band I but gentler in Band II. These results were applied to Mare Humorum and Mare Nubium, and the measurements were found to mainly vary from intermediate- to high-Ca pyroxene.

关键词： techniques spectroscopic methods data analysis instrumentation spectrographs

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Quantifying key model parameters for wheat leaf gas exchange under different environmental conditions

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Journal of Integrative Agriculture 2020年第9期19卷 2188-2205页

作者： ZHAO Fu-nian ZHOU Shuang-xi WANG Run-yuan zhang Kai WANG He-ling yu Qiang Key Laboratory of Water Cycle&Related Land Surface Processes/institute of geographic Sciences and Natural Resources {2. Chinese Academy of SciencesBeijing 100101P.R.China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049P.R.China Key Laboratory of Arid Climatic Change and Disaster Reduction of Gansu Province/Key Laboratory of Arid Climate Change and Disaster Reduction of china Meteorological Administration(CMA)/Lanzhou institute of Arid Meteorology CMALanzhou 730020P.R.China The New Zealand institute for Plant and Food research Limited Hawke's Bay 4130New Zealand State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau/institute of Soil and Water Conservation Northwest A&F UniversityYangling 712100P.R.China School of Life Sciences University of Technology SydneySydney 2000Australia

The maximum carboxylation rate of Rubisco(Vcmax)and maximum rate of electron transport(Jmax)for the biochemical photosynthetic model,and the slope(m)of the Ball-Berry stomatal conductance model influence gas exchange estimates between plants and the ***,there is limited data on the variation of these three parameters for annual crops under different environmental *** exchange measurements of light and CO2.response curves on leaves of winter wheat and spring wheat were conducted during the wheat growing season under different environmental *** were no significant differences for Vcmax,Jmax or m between the two wheat *** seasonal variation of Vcmax,Jmax and m for spring wheat was not pronounced,except a rapid decrease for Vcmax and Jmax at the end of growing *** and Jmax show no significant changes during soil drying until light saturated stomatal conductance(gssat)was smaller than 0.15 mol m^–2.s^–***,there was a significant difference in m during two different water supply conditions separated by gssat at 0.15 mol m^–2.s^–***,the misestimation of Vcmax and Jmax had great impacts on the net photosynthesis rate simulation,whereas,the underestimation of m resulted in underestimated stomatal conductance and transpiration rate and an overestimation of water use *** work demonstrates that the impact of severe environmental conditions and specific growing stages on the variation of key model parameters should be taken into account for simulating gas exchange between plants and the ***,modification of m and Vcmax(and Jmax)successively based on water stress severity might be adopted to simulate gas exchange between plants and the atmosphere under drought.

关键词： biochemical photosynthetic model stomatal conductance model maximum carboxylation rate of Rubisco maximum rate of electron transport drought

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Lagged climatic effects on carbon fluxes over three grassland ecosystems in china

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Journal of Plant Ecology 2015年第3期8卷 291-302页

作者： Tao zhang Mingjie Xu Yi Xi Juntao Zhu Li Tian Xianzhou zhang Yanfen Wang Yingnian Li Peili Shi Guirui {2. Xiaomin Sun Yangjian zhang Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of chinese academy of Sciences Beijing 100049China Northwest institute of Plateau Biology Chinese Academy of SciencesXining 810001China

Aims The plasticity of ecosystem responses could buffer and post-pone the effects of climates on ecosystem carbon fluxes,but this lagged effect is often *** this study,we used carbon flux data collected from three typical grassland ecosystems in china,including a temperate semiarid steppe in Inner mongolia(Neimeng site,Nm),an alpine shrub-meadow in Qinghai(Haibei site,Hb)and an alpine meadow steppe in Tibet(Dangxiong site,DX),to examine the time lagged effects of environmental factors on CO_(2. *** Eddy covariance data were collected from three typical chinese *** linking carbon fluxes with climatic factors,we used their averages or cumulative values within each 12.month period and we called them‘yearly’statistics in this *** investigate the lagged effects of the climatic factors on the car-bon fluxes,the climatic‘yearly’statistics were kept still and the‘yearly’statistics of the carbon fluxes were shifted backward 1 month at a *** Findingssoil moisture and precipitation was the main factor driving the annual variations of carbon fluxes at the alpine Hb and DX,respectively,while the Nm site was under a synthetic impact of each climatic *** time lagged effect analysis showed that temperature had several months,even half a year lag effects on Co2.exchange at the three studied sites,while moisture’s effects were mostly exhibited as an immediate manner,except at *** general,the lagged climatic effects were relatively weak for the alpine *** results implied that it might be months or even 1 year before the variations of ecosystem carbon fluxes are adjusted to the current climate,so such lag effects could be resistant to more frequent climate extremes and should be a critical component to be considered in evaluating ecosystem *** improved knowledge on the lag effects could advance our understanding on the driving mechanisms of climate change effects on ecosystem carbon fluxes.

关键词： climate change carbon flux direct effect grasslands lagged effect

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Spatial patterns and driving forces of land use change in china during the early 2.st century

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Journal of geographical Sciences 2010年第4期20卷 483-494页

作者： liu Jiyuan {2. Zengxiang XU Xinliang KUANG Wenhui ZHOU Wancun {2. Shuwen LI Rendong YAN Changzhen yu Dongsheng WU Shixin JIANG Nan institute of geographic Sciences and Natural Resources {2. CAS Beijing 100101 China institute of Remote Sensing Applications CAS Beijing 100101 China Chengdu institute of Mountain Hazards and Environment CAS Chengdu 610041 China Northeast institute of Geography and Agroecology CAS Changchun 130012 China Wuhan institute of Geodesy and Geophysics CAS Wuhan 430077 China Cold and Arid Regions Environmental and Engineering research institute CAS Lanzhou 730000 China Nanjing institute of Soil Science CAS Nanjing 210008 China Xinjiang institute of Ecology and Geography CAS Urumqi 830011 China Nanjing institute of Geography and Limnology CAS Nanjing 210008 China

Land use and land cover change as the core of coupled human-environment systems has become a potential field of land change science （LCS） in the study of global environmental change. Based on remotely sensed data of land use change with a spatial resolution of 1 km × 1 km on national scale among every 5 years, this paper designed a new dynamic regionalization according to the comprehensive characteristics of land use change including regional differentiation, physical, economic, and macro-policy factors as well. Spatial pattern of land use change and its driving forces were investigated in china in the early 2. st century. To sum up, land use change pattern of this period was characterized by rapid changes in the whole country. Over the agricultural zones, e.g., Huang-Huai-Hai Plain, the southeast coastal areas and Sichuan Basin, a great proportion of fine arable land were engrossed owing to considerable expansion of the built-up and residential areas, resulting in decrease of paddy land area in southern china. The development of oasis agriculture in Northwest china and the reclamation in Northeast china led to a slight increase in arable land area in northern china. Due to the ＂Grain for Green＂ policy, forest area was significantly increased in the middle and western developing regions, where the vegetation coverage was substantially enlarged, likewise. This paper argued the main driving forces as the implementation of the strategy on land use and regional development, such as policies of ＂Western Development＂, ＂Revitalization of Northeast＂, coupled with rapidly economic development during this period.

关键词： land use change spatial pattern driving forces the early 2.st century china

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1900年以来贝加尔湖水位变化及其原因分析

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资源科学 2018年第11期40卷 2177-2185页

作者：王冠王平王田野李泽红于静洁刘昌明 Bolgov M.V. 中国科学院地理科学与资源研究所陆地水循环及地表过程重点实验室北京100101 中国科学院大学北京100049 中国科学院地理科学与资源研究所资源利用与环境修复重点实验室北京100101 俄罗斯科学院水问题研究所莫斯科119333 罗蒙诺索夫莫斯科国立大学陆地水文系莫斯科119991

水位变化作为湖泊水文过程和水量平衡的动态反映,是湖泊生态环境的重要影响因素。全球最大的淡水湖——贝加尔湖,在自然变化与人为活动的双重影响下,过去100多年水位表现出较大的年内、年际和多年变化。贝加尔湖水位变化与入湖径流量变... 详细信息

水位变化作为湖泊水文过程和水量平衡的动态反映,是湖泊生态环境的重要影响因素。全球最大的淡水湖——贝加尔湖,在自然变化与人为活动的双重影响下,过去100多年水位表现出较大的年内、年际和多年变化。贝加尔湖水位变化与入湖径流量变化密切相关,与贝加尔湖最大支流色楞格河的径流量变化较为一致。气候变暖带来的气温上升和降水减少使得入湖径流量减少,贝加尔湖水位下降。人类活动对贝加尔湖水位变化影响表现在两个方面:一方面,全球变暖条件下耕地面积扩张和灌溉用水增加导致贝加尔湖流域用水增加,使得入湖径流量减少,贝加尔湖水位下降;另一方面,1958年伊尔库茨克水电站投入运营之后,贝加尔湖水位变化受到了安加拉河水位顶托的影响。在下游水电站人为调控影响下,贝加尔湖年平均水位升高,年内水位波动幅度增加,年最低和最高水位出现日期推迟。地处全球气候与环境变化敏感区的贝加尔湖,其水位变化对湖泊及周边生态环境影响显著。因此,探究在全球变化背景下贝加尔湖的水位变化及影响因素对保护当地生态环境具有重要意义。

关键词：贝加尔湖水位气候变化伊尔库茨克水电站

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An Introduction to the chinese High-Resolution Earth Observation System:Gaofen-1~7 Civilian Satellites

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Journal of Remote Sensing 2022年第1期2022卷 244-257页

作者： Liangfu Chen Husi Letu Meng Fan Huazhe Shang Jinhua Tao Laixiong Wu Ying zhang Chao yu Jianbin Gu Ning zhang Jin Hong Zhongting Wang Tianyu zhang State Key Laboratory of Remote Sensing Science The Aerospace Information Research InstituteChinese Academy of Sciences(CAS)Datun Road No.20(North)Beijing 100101China University of chinese academy of Sciences(UCAS) Beijing 100101China Remote Sensing Application Center Ministry of Housing and Urban-Rural Development of the People’s Republic of ChinaSanlihe Road No.9 Beijing 100835China Key Laboratory of Optical Calibration and Characterization of chinese academy of Science Anhui Institute of Optics and Fine MechanicsChinese Academy of SciencesHefei 230031China Center for Satellite Application on Ecology and Environment Ministry of Ecology and EnvironmentBeijing 100006China

The chinese High-resolution Earth Observation System(CHEOS)program has successfully launched 7 civilian satellites since *** satellites are named by Gaofen(meaning high resolution in chinese,hereafter noted as GF).To combine the advantages of high temporal and comparably high spatial resolution,diverse sensors are deployed to each ***-1 and GF-6 carry both high-resolution cameras(2. resolution panchromatic and 8m resolution multispectral camera),providing high spatial imaging for land use monitoring;GF-{2.is equipped with a C-band multipolarization synthetic aperture radar with a spatial resolution of up to 1 meter,mostly monitoring marine targets;GF-5 carried 6 sensors including hyperspectral camera and directional polarization camera,dedicated to environmental remote sensing and climate research,such as aerosol,clouds,and greenhouse gas monitoring;and GF-7 laser altimeter system payload enables a three-dimensional surveying and mapping of natural resource and land surveying,facilitating the accumulation of basic {{2. *** study provides an overview of GF civilian series satellites,especially their missions,sensors,and applications.

关键词： payload Earth surveying

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Fe-Zn基废脱硫剂制备铁碳材料及其对废水微电解性能

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化工学报 2020年第2期71卷 788-798页

作者：张霄玲于凤芹皇甫林王超李长明高士秋余剑中国科学院大学化学与化工学院北京100049 中国科学院过程工程研究所多相复杂系统国家重点实验室北京100190 湘潭大学化工学院湖南湘潭411105

以Fe-Zn基废脱硫剂、煤、Na2.O3.原料进行高温炭热还原反应,制备了铁碳材料,实现了Zn和S的分离,有望能实现废脱硫剂的综合利用。考察不同工艺条件(配比,温度,时间)对铁碳材料品质,Zn单质分离效率和Na2.的收率影响。结果表明:反应温度≥... 详细信息

以Fe-Zn基废脱硫剂、煤、Na2.O3.原料进行高温炭热还原反应,制备了铁碳材料,实现了Zn和S的分离,有望能实现废脱硫剂的综合利用。考察不同工艺条件(配比,温度,时间)对铁碳材料品质,Zn单质分离效率和Na2.的收率影响。结果表明:反应温度≥900℃,煤∶废脱硫剂≥1,Na2.O3.废脱硫剂≥1.5,反应时长≥2.,Zn、S的分离回收效率可达到95%以上。且900℃制备的铁碳材料比表面高达193.6 m^2.g,介孔孔体积为0.02.cm^3.g,炭均匀附着于铁骨架。微电解-芬顿联用降解有机废水实验表明:仅微电解或微电解-芬顿联用(H2.2.COD=1500 mg/L)时,自制铁碳材料的稳定化学需氧量(COD)去除效率(41.78%、73.56%)都高于商业铁碳(8.43.、48.43.)。本文实验结果表明废脱硫剂与煤和碳酸钠混烧可实现废脱硫剂中Zn与S的分离回收,成功获得了比表面高、去除COD性能好的铁碳材料。

关键词： Fe-Zn基废脱硫剂炭热还原微电解-芬顿 COD

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生态水文学兴起:学科理论与实践问题的评述

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北京师范大学学报（自然科学版） 2022年第3期58卷 412-423页

作者：刘昌明刘璇于静洁杨胜天赵长森门宝辉赵志龙王红瑞北京师范大学水科学研究院城市水循环与海绵城市技术北京市重点实验室北京100875 中国科学院地理科学与资源研究所陆地水循环及地表过程重点实验室北京100101 中国科学院大学北京100049 华北电力大学水利与水电工程学院北京102206

生态水文学是2.世纪后半叶发展起来的新兴水科学研究领域的交叉综合学科,基于习近平总书记的“生态优先、绿色发展”理念和实现我国生态文明建设目标,其研究成为我国新时期水科学理论与实践的新目标与新挑战,为“绿色-高质量-可持续”... 详细信息

生态水文学是2.世纪后半叶发展起来的新兴水科学研究领域的交叉综合学科,基于习近平总书记的“生态优先、绿色发展”理念和实现我国生态文明建设目标,其研究成为我国新时期水科学理论与实践的新目标与新挑战,为“绿色-高质量-可持续”发展提供强大动力.本文简述了生态水文学国内外发展历程和动向,深入评述了生态水文研究的几个基础理论问题,主要包括:人-水-生态系统关系认知与协同变化的和谐内涵、四大平衡的协同内涵及Budyko水-热平衡联系方程、绿水在生态系统中的重要内容和面向全球变化的生态水文宏微观尺度研究,并着重阐述了生态系统的需水与用水;针对生态水文的实践应用,阐述了水-碳循环耦合机制研究能够有效服务国家“双碳”计划,分析了南水北调工程和黄河流域生态环境治理中生态水文问题,提出了南水北调西线工程是构建国家水网、缓解黄河流域水资源短缺的重要举措;基于生态水文研究现状和国家发展需求,对生态水文研究提出展望,如生态系统对人类活动和气候变化响应机制研究、水土保持与生态建设综合技术体系、多源信息融合新技术、加强与社会科学的交叉融合研究和生态水文系统研究等.

关键词：生态水文人-水-生态系统生态需水黄河流域水碳耦合

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