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Latitudinal variation of leaf morphological traits from species to communities along a forest transect in eastern China

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Journal of Geographical Sciences 2016年第1期26卷 15-26页

作者：王瑞丽于贵瑞何念鹏王秋凤赵宁徐志伟 Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchCAS University of Chinese Academy of Sciences Cold and Arid Regions Environmental and Engineering Research Institute CAS School of Geographical Sciences Northeast Normal University

Comprehensive information on geographic patterns of leaf morphological traits in Chinese forests is still *** explore the spatial patterns of leaf traits,we investigated leaf area(LA),leaf thickness(LT),specific leaf area(SLA),and leaf dry matter content(LDMC) across 847 species from nine typical forests along the North-South Transect of Eastern China(NSTEC) between July and August 2013,and also calculated the community weighted means(CWM) of leaf traits by determining the relative dominance of each *** results showed that,for all species,the means(± SE) of LA,LT,SLA,and LDMC were 2860.01 ± 135.37 mm2,0.17 ± 0.003 mm,20.15 ± 0.43 m2 kg–1,and 316.73 ± 3.81 mg g–1,***,latitudinal variation in leaf traits differed at the species and community ***,at the species level,SLA increased and LDMC decreased as latitude increased,whereas no clear latitudinal trends among LA or LT were found,which could be the result of shifts in plant functional *** scaling up to the community level,more significant spatial patterns of leaf traits were observed(R2 = 0.46–0.71),driven by climate and soil N *** results provided synthetic data compilation and analyses to better parameterize complex ecological models in the future,and emphasized the importance of scaling-up when studying the biogeographic patterns of plant traits.

关键词： latitudinal pattern leaf morphological trait community weighted mean forest ecosystem North-South Transect of Eastern China

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Ozone concentrations, flux and potential effect on yield during wheat growth in the NorthwestShandong Plain of China

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Journal of Environmental Sciences 2015年第8期27卷 1-9页

作者： Zhilin Zhu Xiaomin Sun Fenghua Zhao Franz X.Meixner Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences Biogeochemistry Department Max-Planck-Institute for Chemistry

Ozone（O3） concentration and flux（Fo） were measured using the eddy covariance technique over a wheat field in the Northwest-Shandong Plain of China. The O3-induced wheat yield loss was estimated by utilizing O3exposure-response models. The results showed that：（1） During the growing season（7 March to 7 June, 2012）, the minimum（16.1 ppb V） and maximum（53.3 ppb V）mean O3 concentrations occurred at approximately 6：30 and 16：00, respectively. The mean and maximum of all measured O3 concentrations were 31.3 and 128.4 ppb V, respectively. The variation of O3 concentration was mainly affected by solar radiation and temperature.（2） The mean diurnal variation of deposition velocity（V d） can be divided into four phases, and the maximum occurred at noon（12：00）. Averaged V d during daytime（6：00–18：00） and nighttime（18：00–6：00） were 0.42 and 0.14 cm/sec, respectively. The maximum of measured V d was about1.5 cm/sec. The magnitude of V d was influenced by the wheat growing stage, and its variation was significantly correlated with both global radiation and friction velocity.（3） The maximum mean F o appeared at 14：00, and the maximum measured F o was-33.5 nmol/（m^2·sec）. Averaged F o during daytime and nighttime were-6.9 and-1.5 nmol/（m^2·sec）, respectively.（4） Using O3 exposure-response functions obtained from the USA, Europe, and China, the O3-induced wheat yield reduction in the district was estimated as 12.9% on average（5.5%–23.3%）. Large uncertainties were related to the statistical methods and environmental conditions involved in deriving the exposure-response functions.

关键词： Ozone concentration Ozone flux Deposition velocity Eddy covariance Yield loss estimation Cropland ecosystem

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Clipping Alters the Response of Biomass Production to Experimental Warming: A Case Study in an Alpine Meadow on the Tibetan Plateau, China

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Journal of Mountain Science 2015年第4期12卷 935-942页

作者： FU Gang SUN Wei YU Cheng-Qun ZHANG Xian-Zhou SHEN Zhen-Xi LI Yun-Long YANG Peng-Wan ZHOU Nan Lhasa Plateau Ecosystem Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences

Predicting how human activity will influence the response of alpine grasslands to future warming has many *** this study, a field experiment with controlled warming and clipping was conducted in an alpine meadow at three elevations（4313 m, 4513 m and 4693 m） in Northern Tibet to test the hypothesis that clipping would alter warming effect on biomass *** top chambers（OTCs） were used to increase temperature since July,2008 and the OTCs increased air temperature by approximately 0.9o C ~ 1.8o C during the growing *** was conducted three times one year during growing season and the aboveground parts of all live plants were clipped to approximately 0.01 m in height using scissors since *** primary production（GPP） was calculated from the Moderate-Resolution Imaging Spectroradiometer GPP algorithm and aboveground plant production was estimated using the surface-measured normalized difference vegetation index in *** decreased the GPP, aboveground biomass（AGB） and aboveground net primary production（ANPP） at all three elevations when clipping was not *** contrast, warming increased AGB at all three elevations, GPP at the two lower elevations and ANPP at the two higher elevations when clipping was *** findings show that clipping reduced the negative effect of warming on GPP, AGB and ANPP, suggesting that clipping may reduce the effect of climate warming on GPP, AGB and ANPP in alpine meadows on the Tibetan Plateau, and therefore, may be a viable strategy for mitigating the effects of climate change on grazing and animal husbandry on the Tibetan Plateau.

关键词： Clipping Gross primary production Open top chamber Warming Alpine Meadow Tibetan Plateau

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Baseflow Characteristics in Alpine Rivers-a Multicatchment Analysis in Northwest China

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Journal of Mountain Science 2015年第3期12卷 614-625页

作者： GAN Rong SUN Lin LUO Yi Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences University of Chinese Academy of Sciences

As a component of streamflow, baseflow is critical for regulating seasonal distribution of river fows and stabilizing water supplies. Water resources in the arid area of Northwest China are mainly from multiple catchments in the alpine that could be influenced by varieties of climatic, land cover, soil and geological factors. While numerous studies have been done on streamflow, systematic analysis of baseflow in the alpine river systems is scare. Based on historical daily streamflow data and the automated digital filter method of baseflow separation, this study investigated characteristics of hydrographs of overland flow, streamflow and baseflowof river systems fed by rainfall, snowmelt, glacier melt or mixtures of these. This study also calculated the recession constants and baseflow indices of 65 river systems. While the recession constant was ***34- o.o728 with a mean of o.o18, the baseflow index was 0.27-0.79 with a mean of 0.57. Further, Spearman＇s correlation analysis showed that the baseflow index was significantly correlated with catchment climatic factors （e.g., precipitation and temperature）, topographic factors （e.g., elevation and slope） and aquifer properties represented by the recession constant. Multiple regression analysis indicated that the factors explained 65% of the variability of baseflow index in the studv area.

关键词： Baseflow index Recession constant Snowmelt Glacier melt Streamflow

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Flux Footprint Climatology Estimated by Three Analytical Models over a Subtropical Coniferous Plantation in Southeast China

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Journal of Meteorological Research 2015年第4期29卷 654-666页

作者：张慧温学发 Jinzhou Ecology and Agriculture Meteorological Center Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

Spatial heterogeneity poses a major challenge for the appropriate interpretation of eddy covariance data. The quantification of footprint climatology is fundamental to improving our understanding of carbon budgets, assessing the quality of eddy covariance data, and upscaling the representativeness of a tower flux to regional or global scales. In this study, we elucidated the seasonal variation of flux footprint climatologies and the major factors that influence them using the analytical FSAM （Flux Source Area Model）, KM （Kormann and Meixner, 2001）, and H （Hsieh et al., 2000） models based on eddy covariance measurements at two and three times the canopy height at the Qianyanzhou site of ChinaFLUX in 2003. The differences in footprints among the three models resulted from different underlying theories used to construct the models. A comparison demonstrated that atmospheric stability was the main factor leading to differences among the three models. In neutral and stable conditions,the KM and FSAM values agreed with each other, but they were both lower than the H values. In unstable conditions, the agreement among the three models for rough surfaces was better than that for smooth surfaces, and the models showed greater agreement for a low measurement height than for a high measurement height. The seasonal flux footprint climatologies were asymmetrically distributed around the tower and corresponded well to the prevailing wind direction, which was north-northwest in winter and south-southeast in summer. The average sizes of the 90% flux footprint climatologies were 0.36 0.74 and 1.5-3.2 kin2 at altitudes of two and three times the canopy height, respectively. The average sizes were ranked by season as follows： spring 〉 summer 〉 winter 〉 autumn. The footprint climatology depended more on atmospheric stability on daily scale than on seasonal scale, and it increased with the increasing standard deviation of the lateral wind fluctuations.

关键词： eddy covariance flux footprint flux footprint climatology model comparison

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Advances in experimental methods for root system architecture and root development

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Journal of Forestry Research 2015年第1期26卷 23-32页

作者： Jun-bang Wang Xiu-juan Zhang Chu Wu Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences College of Horticulture and Gardening Yangtze University

Plant roots play important roles in acquisition of water and nutrients, storage, anchoring, transport, and symbiosis with soil microorganisms, thus quantitative researches on root developmental processes are essential to understand root functions and root turnover in ecosystems,and at the same time such researches are the most difficult because roots are hidden underground. Therefore, how to investigate efficiently root functions and root dynamics is the core aspect in underground ecology. In this article, we reviewed some experimental methods used in root researches on root development and root system architecture, and summarized the advantages and shortages of these methods. Based on the analyses, we proposed three new ways to more understand root processes：（1） new experimental materials for root development;（2） a new observatory system comprised of multiple components, including many observatory windows installed in field, analysis software,and automatic data transport devices;（3） new techniques used to analyze quantitatively functional roots.

关键词： Root system analysis Fractal geometry Novel materials

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Flux Footprint Climatology Estimated by Three Analytical Models of a Subtropical Coniferous Plantation in Southeastern China

Flux Footprint Climatology Estimated by Three Analytical Mod...

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第33届中国气象学会年会

作者：张慧温学发史奎桥杨扬 Jinzhou Ecology and Agriculture Meteorological Center Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences

Spatial heterogeneity poses a major challenge for the appropriate interpretation of eddy covariance data. The quantification of footprint climatology is fundamental to improve our understanding of carbon budgets, assessing the quality of eddy covariance data, and upscaling the representativeness of a tower flux to regional or global scales. In this study, we elucidated the seasonal variation of flux footprint climatologies and the major factors that influence them using the analytical FSAM, KM, and H models based on eddy covariance measurements at two and three times the canopy height at the Qianyanzhou site of China FLUX in 2003. The differences in footprints among the three models resulted from different underlying theories used to construct the models. An inter-comparison demonstrated that atmospheric stability was the main factor leading to differences among the three models. In neutral and stable conditions, the KM and FSAM values agreed with one another, but were lower than the H values. In unstable conditions, the agreement among the three models for rough surfaces was better than that for smooth surfaces, and the models showed greater agreement for a low measurement height than for a high measurement height. The seasonal flux footprint climatologies were asymmetrically distributed around the tower and corresponded well to the prevailing wind direction, which was north-northwest in winter and south-southeast in summer. The average sizes of the 90% flux footprint climatologies were 0.36–0.74 km and 1.5–3.2 km at altitudes of two and three times the canopy height, respectively. The average sizes were ranked by season as follows: spring > summer > winter > autumn. The footprint climatology clearly depended more on atmospheric stability on a daily scale than on a seasonal scale, and it increased with the increasing standard deviation of the lateral wind fluctuations.

关键词： eddy covariance flux footprint flux footprint climatology model comparison

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REE characteristic and significance of DongChuan red clay resource in Kunming, China 4

REE characteristic and significance of DongChuan red clay re...

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4th Academic Conference of Geology Resource Management and Sustainable Development

作者： Di, Yingwei Cong, Diange Feng, Yunfei Institute of Earth Sciences China University of Geosciences Beijing100083 China Depratment of Geological Engineering Qinghai University Xining810016 China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Beijing100101 China University of Chinese Academy of Sciences Beijing100049 China

ISBN: (纸本)9781921712494

The southern red clay is the most extensively developed and utilized red clay resourse at present. Many mineral resources such as lateritic nickel ore, lateritic gold deposit and lateritic bauxite are stored in such red clay. The research efforts in this area focus on the distribution, provenance, cause of formation, stratigraphic age and the development level of the red earth, and the research findings will surely benefit the development and utilization of the red clay resourse. This study analysed the contents of REE, the rare earth elements' distribution patterns and characteristic parameters and characteristic values of the red clay in Dongchuan area. The results show that the main sendimentary source of the Dongchuan RH profile may be the purple-red sandstone, the red clay may have experienced strong weathering during its formation and appears the characteristics of ferrallitic-rich weathering crust which represents a warm and humid climate and environment, all of which meet the necessary conditions of the formation of the lateritic bauxite resources.

关键词： Gold deposits

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Vertical Distribution of Soil Carbon, Nitrogen, and Phosphorus in Typical Chinese Terrestrial ecosystems

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Chinese Geographical Science 2015年第5期25卷 549-560页

作者： CHAI Hua YU Guirui HE Nianpeng WEN Ding LI Jie FANG Jiangping Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Agriculture and Animal Husbandry College of Tibet University

Characterization of the vertical distribution of soil organic carbon(C), nitrogen(N), and phosphorus(P) may improve our ability to accurately estimate soil C, N, and P storage. Based on a database of 21 354 records in 74 long-term monitoring plots from 2004 to 2013 in the Chinese ecosystem Research network(CERN), we built fitting functions to quantify the vertical distribution of soil C, N, and P(up to 100 cm depth) in the typical Chinese terrestrial ecosystems. The decrease of soil C, N, and P content with depth can be well fitted with various mathematical functions. The fitting functions differed greatly between artificial(agriculture) and natural(desert, forest, and grassland) ecosystems, and also differed with respect to soil C, N, and P content. In both the artificial and natural ecosystems, the best fitting functions were exponential functions for C, quadratic functions for N, and quadratic functions for P. Furthermore, the stoichiometric ratios of soil C, N, and P were ranked in descending order: grassland > forest > agriculture > desert, and were also associated with climate. This study is the first to build the fitting functions for the profile distribution of soil C, N, and P in China at a national scale. Our findings provide a scientific basis to accurately assess the storage of C, N, and P in soils at a large scale, especially for the integrative analysis of historical data.

关键词： soil profile storage stoichiometry vertical distribution China

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Nitrogen acquisition strategies used by Leymus chinensis and Stipa grandis in temperate steppes

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BIOLOGY AND FERTILITY OF SOILS 2016年第7期52卷 951-961页

作者： Wang, Ruixue Tian, Yuqiang Ouyang, Shengnan Xu, Xingliang Xu, Fanzhen Zhang, Yong Beijing Normal Univ CHESS State Key Lab Earth Surface Proc & Resource Ecol Beijing 100875 Peoples R China Chinese Acad Sci Inst Geog Sci & Nat Resources Res Key Lab Ecosystem Network Observat & Modeling Beijing 100101 Peoples R China Laibin Inst Agr Sci Laibin Guangxi Provinc Peoples R China Chinese Acad Agr Sci Inst Grassland Res Hohhot 010010 Peoples R China

Leymus chinensis and Stipa grandis are two important plant species of temperate steppes in Inner Mongolia of North China. They differ in their life forms, e.g., L. chinensis is a type of rhizomatous clonal grass, whereas S. grandis is a type of tussock grass. Here we hypothesize that both plant species possess distinct nitrogen (N) acquisition strategies for their growth and survival. To test this hypothesis, we conducted a four-factor experimental field study using a short-term (three hours) N-15 labeling technique in two plant communities mono-dominated by L. chinensis and S. grandis of the temperate steppes over two months (July and August) and at two soil depths. In both of communities, L. chinensis and S. grandis directly absorbed all three of the common forms of N, including substantial portions of N-derived from glycine (organic and inorganic forms) ranged from 2.7 to 17.8 %, although they absorbed more inorganic N. Nitrogen uptake rates showed significant effects of communities, months, soil depths, and N forms. The uptake rate was higher in August than in July and at 0-5 cm than at 5-15 cm soil depths. L. chinensis and S. grandis showed different preference on N form across months. L. chinensis shifted its uptake pattern from more nitrate (NO3 (-)) in July to more ammonium (NH4 (+)) in August, whereas S. grandis took up comparable NH4 (+) and NO3 (-) in both months. In general, L. chinensis showed a more flexible N acquisition strategy and S. grandis performed a more concentrated and relatively more stable N acquisition strategy. The distinct N acquisition strategies used by L. chinensis and S. grandis varied greatly across different months and soil depths. These findings are more helpful in further understanding the plasticity of nutrient utilization issues of different plant species in response to N-limited conditions of grassland ecosystems.

关键词： Organic nitrogen Nitrogen acquisition strategies Life form Monodominant community Temperate steppes

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