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Latitudinal pattern and the driving factors of leaf functional traits in 185 shrub species across eastern China

Journal of Plant Ecology 2019年第1期12卷 67-77页

作者： yongkai luo Huifeng Hu Mengying Zhao He Li Shangshi Liu Jingyun Fang State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesNo.20 NanxincunXiangshanBeijing 100093China University of Chinese Academy of Sciences 19 A Yuquan RdShijingshan DistrictBeijing 100049China College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityNo.5 Yiheyuan RdHaidian DistrictBeijing 100871China

Aims To explore the pattern of the leaf functional traits of shrub species along a latitudinal gradient in eastern China and determine the driv-ing factors of leaf trait variation at a large *** We investigated the leaf thickness(LT),leaf area(LA),specific leaf area(SLA)and leaf dry mass content(LDMC)of 185 shrub species from 13 sites across eastern *** trends of these four-leaf traits were ana-lyzed with respect to latitude,and the differences between different life forms(e.g.,evergreen and deciduous)and habitats(e.g.,understory and typical)were *** quantified the effects of the plant life forms and environmental factors on the leaf traits via mixed-model *** Findings The LT and LA decreased,whilst and the LDMC increased,as the latitude increased,and significant differences in these traits were observed between the different plant life *** LT and LA were smaller,whereas the SLA and LDMC were larger in decidu-ous shrubs than in evergreen *** the different habitats,the LA and SLA were larger,while the LDMC was smaller in under-story shrubs than in typical shrub *** results indicate that typical shrub species are better adapted to drier environments,as indicated by a reduced LT and increased ***,general linear models showed that variations in the four-leaf traits with respect to latitude were mainly caused by a shift in plant life forms.

关键词： shrub species leaf functional traits latitude trend different life forms eastern China

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Resorption efficiency of leaf nutrients in woody plants on Mt. Dongling of Beijing, North China

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Journal of Plant Ecology 2015年第5期8卷 530-538页

作者： Jianhua Zhang Zhiyao Tang yongkai luo Xiulian Chi Yahan Chen Jingyun Fang Haihua Shen State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesNo.20 NanxincunXiangshanBeijing 100093China University of Chinese Academy of Sciences No.19A Yuquan RoadShijingshan DistrictBeijing 100049China Department of Ecology College of Urban and Environmental Sciences and Key Laboratory for Earth Surface ProcessesPeking UniversityNo.5 Yiheyuan RoadHaidian DistrictBeijing 100871China

Aims To explore resorption efficiency of nitrogen(NrE)and phosphorus(PrE)of woody plants in relation to soil nutrient availability,climate and evolutionary history,in North *** We measured concentrations of nitrogen([N])and phosphorus([P])in both full expanded mature green and senescent leaves of the same individuals for 88 woody species from 10 sites of ***,beijing,*** built a phylogenetic tree for all these species and compared NrE and PrE among life forms(trees,shrubs and woody lianas)and between functional groups(N-fixers and non-N-fixers).We then explored patterns of NrE and PrE along gradients of mean annual temperature(MAT),soil inorganic N and available P,and phylogeny using a general linear *** Findingsmass-based NrE(NrEm)and PrE(PrEm)averaged 57.4 and 61.4%,respectively,with no significant difference among life forms or functional *** NrEm nor PrEm exhibited significant phylogenetic signals,indicating that NrEm and PrEm were not phylogenetically *** was not related to[N]in green leaves;PrEm was positively correlated with[P]in green leaves;however,this relationship disappeared for different *** decreased with[N]in senescent leaves,PrEm decreased with[P]in senescent leaves,for all species combined and for trees and *** decreased with soil inorganic N for all species and for shrubs;PrEm did not exhibit a significant trend with soil available P for all species or for different plant *** NrEm nor PrEm was significantly related to MAT for overall species and for species of different groups.

关键词： nitrogen concentration phosphorus concentration senesced leaves nitrogen resorption efficiency phosphorus resorption efficiency soil nutrient climate

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Yield and quality properties of silage maize and their influencing factors in China

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Science China(Life Sciences) 2022年第8期65卷 1655-1666页

作者： Mengying Zhao Yinping Feng Yue Shi Haihua Shen Huifeng Hu yongkai luo Longchao Xu Jie Kang Aijun Xing Shaopeng Wang Jingyun Fang State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871China

Silage maize(Zea mays L.) is one of the most important forages in the world, and its yield and quality properties are critical parameters for livestock production and assessment of forage values. However, relationships between its yield and quality properties and the controlling factors are not well documented. In this study, we collected 5,663 observations from 196 publications across the country to identify the relationships between yield and quality properties of silage maize and to assess the impact of management practices and climatic factors on its yield and quality in China. The average dry matter yield of silage maize was(19.98±6.93) Mg ha^(-1), and the average value of crude protein, ether extract, crude ash, crude fiber, acid detergent fiber, neutral detergent fiber, nitrogen-free extract, and relative feed value was 7.86%±1.71%, 2.53%±1.01%, 5.05%±1.66%,23.97%±6.34%, 27.62%±7.12%, 51.60%±9.85%, 59.68%±7.72%, and 131.17±31.49, respectively. In general, its nutritive value decreased as its yield increased. Increasing planting density could increase the yield but inhibit the nutritive values, while increasing fertilization could benefit the nutritive values. Geographically, the yield increased and the nutritive value decreased from warm(south) to cold(north) regions. The length of growth duration was a major controlling factor for the patterns of these properties. Our findings provide insights for police-makers to make strategy for achieving high yield and good quality of silage maize and help local people to implement better management practices.

关键词： silage maize yield quality management practices climatic factors

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Family-level leaf nitrogen and phosphorus stoichiometry of global terrestrial plants

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Science China(Life Sciences) 2019年第8期62卷 1047-1057页

作者： Di Tian Zhengbing Yan Suhui Ma Yuehong Ding yongkai luo Yahan Chen Enzai Du Wenxuan Han Emoke Dalma Kovacs Haihua Shen Huifeng Hu Jens Kattge Bernhard Schmid Jingyun Fang College of Life Sciences Capital Normal UniversityBeijing100048China Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry ofEducationPeking UniversityBeijing100871China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing100093China College of Resources Science&Technology and State Key Laboratory of Earth Surface Processes and Resource EcologyBeijing NormalUniversityBeijing100875China Key Laboratory of Plant-Soil Interactions Ministry of EducationCollege of Resources and Environmental SciencesChina AgriculturalUniversityBeijing100193China National Institute for Research and Development in Optoelectronics INCDO-INOE2000 Research Institute for Analytical InstrumentationICIA subsidiaryCluj-Napoca400293Romania Max-Planck-Institute for Biogeochemistry Jena07745Germany Department of Evolutionary Biology and Environmental Studies University of ZurichZurich8057Switzerland

Leaf nitrogen(N) and phosphorus(P) concentrations are critical for photosynthesis, growth, reproduction and other ecological processes of plants. Previous studies on large-scale biogeographic patterns of leaf N and P stoichiometric relationships were mostly conducted using data pooled across taxa, while family/genus-level analyses are rarely reported. Here, we examined global patterns of family-specific leaf N and P stoichiometry using a global data set of 12,716 paired leaf N and P records which includes 204 families, 1,305 genera, and 3,420 species. After determining the minimum size of samples(i.e., 35 records), we analyzed leaf N and P concentrations, N:P ratios and N^P scaling relationships of plants for 62 families with 11,440 records. The numeric values of leaf N and P stoichiometry varied significantly across families and showed diverse trends along gradients of mean annual temperature(MAT) and mean annual precipitation(MAP). The leaf N and P concentrations and N:P ratios of 62 families ranged from 6.11 to 30.30 mg g–1, 0.27 to 2.17 mg g–1, and 10.20 to 35.40, respectively. Approximately 1/3–1/2 of the families(22–35 of 62) showed a decrease in leaf N and P concentrations and N:P ratios with increasing MAT or MAP, while the remainder either did not show a significant trend or presented the opposite pattern. Family-specific leaf N^P scaling exponents did not converge to a certain empirical value, with a range of 0.307–0.991 for 54 out of 62 families which indicated a significant N^P scaling relationship. Our results for the first time revealed large variation in the family-level leaf N and P stoichiometry of global terrestrial plants and that the stoichiometric relationships for at least one-third of the families were not consistent with the global trends reported previously. The numeric values of the family-specific leaf N and P stoichiometry documented in the current study provide critical synthetic parameters for biogeographic modeling and for further stud

关键词： leaf nitrogen (N) leaf phosphorus (P) plant stoichiometry family N:P ratios N^P scaling relationship climate

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Global leaf nitrogen and phosphorus stoichiometry and their scaling exponent

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National Science Review 2018年第5期5卷 728-739页

作者： Di Tian Zhengbing Yan Karl J.Niklas Wenxuan Han Jens Kattge Peter B.Reich yongkai luo Yahan Chen Zhiyao Tang Huifeng Hu Ian J.Wright Bernhard Schmid Jingyun Fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University Max-Planck-Institute for Biogeochemistry State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences College of Life Sciences Capital Normal University Department of Plant Biology Cornell University Department of Forest Resources University of Minnesota Department of Biological Sciences Macquarie UniversitySydneyNSW 2109Australia10 Department of Evolutionary Biology and Environmental StudiesUniversity of Zurich Hawkesbury Institute for the Environment Western Sydney University Key Laboratory of Plant-Soil Interactions Ministry of EducationCollege of Resources and Environmental SciencesChina Agricultural University

Leaf nitrogen(N) and phosphorus(P) concentrations constrain photosynthetic and metabolic processes,growth and the productivity of plants. Their stoichiometry and scaling relationships regulate the allocation of N and P from subcellular to organism, and even ecosystem levels, and are crucial to the modelling of plant growth and nutrient cycles in terrestrial ecosystems. Prior work has revealed a general biogeographic pattern of leaf N and P stoichiometric relationships and shown that leaf N scales roughly as two-thirds the power of P. However, determining whether and how leaf N and P stoichiometries, especially their scaling exponents, change with functional groups and environmental conditions requires further verification. In this study, we compiled a global data set and documented the global leaf N and P concentrations and the N:P ratios by functional group, climate zone and continent. The global overall mean leaf N and P concentrations were 18.9 mg gand 1.2 mg g, respectively, with significantly higher concentrations in herbaceous than woody plants(21.72 mg gvs. 18.22 mg gfor N; and 1.64 mg gvs. 1.10 mg gfor P). Both leaf N and P showed higher concentrations at high latitudes than low latitudes. Among six continents, Europe had the highest N and P concentrations(20.79 and 1.54 mg g) and Oceania had the smallest values(10.01 and 0.46 mg g). These numerical values may be used as a basis for the comparison of other individual studies. Further, we found that the scaling exponent varied significantly across different functional groups,latitudinal zones, ecoregions and sites. The exponents of herbaceous and woody plants were 0.659 and0.705, respectively, with significant latitudinal patterns decreasing from tropical to temperate to boreal zones. At sites with a sample size ≥10, the values fluctuated from 0.366 to 1.928, with an average of *** factors including the intrinsic attributes of different life forms, P-related growth rates and relative nutrient availa

关键词： leaf nitrogen phosphorus stoichiometry scaling exponent functional group biogeography

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Food-Borne Poisoning Accident from Amanitin Toxin in Wild Mushrooms—Xingtai City,Hebei Province,China,2023

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China CDC weekly 2024年第3期6卷 56-59页

作者： Baopu Lv Liang Liu Hao Xiao Qingbing Meng Rui Zhang Yaqing An Yingli Jin Yu Ma Hengbo Gao yongkai Li Qian He Yutao Zhang Changqing Liu Xiaoyan luo Xiaomin Xu Fenshuang Zheng Yingping Tian Hongshun Zhang Dongqi Yao Emergency Department The Second Hospital of Hebei Medical UniversityShijiazhuang CityHebei ProvinceChina National Institute of Occupational Health and Poison Control Chinese Centre for Disease Control and PreventionBeijingChina Hebei Provincial Center for Disease Control and Prevention Shijiazhuang CityHebei ProvinceChina Zhejiang Provincial Center for Disease Control and Prevention Hangzhou CityZhejiang ProvinceChina Emergency Department The Affiliated Hospital of Yunnan UniversityKunming CityYunnan ProvinceChina

What is already known about this topic?Fatal poisonings caused by wild mushrooms containing amanita toxins pose a significant threat in the southern regions of *** toxins primarily induce gastrointestinal symptoms initially,which are then followed by potentially life-threatening acute liver *** is added by this report?This report contributes to the existing knowledge on these cases of poisoning by documenting the second occurrences in Hebei Province and the first occurrences in Xingtai *** individuals reported consuming wild mushrooms from the same origin,and laboratory tests confirmed the presence ofα-amanitin in their blood *** are the implications for public health practice?This underscores the risk associated with the collection and consumption of amanita toxin-containing mushrooms in *** is important to note that the identification of toxic and non-toxic mushrooms should not solely rely on personal experience or appearance.

关键词： Hebei consuming initially

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On fine-grained visual explanation in convolutional neural networks

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Digital Communications and Networks 2023年第5期9卷 1141-1147页

作者： Xia Lei yongkai Fan Xiong-Lin luo Department of Automation China University of Petroleum BejingBeijing102249China State Key Laboratory of Media Convergence and Communication Communication University of ChinaBeijing100024China

Existing explanation methods for Convolutional Neural Networks(CNNs)lack the pixel-level visualization explanations to generate the reliable fine-grained decision *** there are inconsistencies between the explanation and the actual behavior of the model to be interpreted,we propose a Fine-Grained Visual Explanation for CNN,namely F-GVE,which produces a fine-grained explanation with higher consistency to the decision of the original *** exact backward class-specific gradients with respect to the input image is obtained to highlight the object-related pixels the model used to make *** addition,for better visualization and less noise,F-GVE selects an appropriate threshold to filter the gradient during the calculation and the explanation map is obtained by element-wise multiplying the gradient and the input image to show fine-grained classification decision *** results demonstrate that F-GVE has good visual performances and highlights the importance of fine-grained decision ***,the faithfulness of the explanation in this paper is high and it is effective and practical on troubleshooting and debugging detection.

关键词： Convolutional neural network Explanation Class-specific gradient Fine-grained

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基于地物高光谱和无人机多光谱的黄河三角洲土壤盐分机器学习反演模型

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智慧农业（中英文） 2022年第4期4卷 61-73页

作者：范承志王梓文杨兴超罗永开徐学欣郭斌李振海山东科技大学测绘与空间信息学院山东青岛266590 滨州学院山东省黄河三角洲生态环境重点实验室山东滨州256603 青岛农业大学农学院山东青岛266109

土壤盐渍化是限制黄河三角洲地区农业经济发展的重要因素,进一步阻碍了农业生产。为了探索无人机影像在地表无植被覆盖条件下的土壤盐分含量反演状况,以黄河三角洲典型区域为研究区,获取地物高光谱和无人机多光谱两种数据源与样点土壤... 详细信息

土壤盐渍化是限制黄河三角洲地区农业经济发展的重要因素,进一步阻碍了农业生产。为了探索无人机影像在地表无植被覆盖条件下的土壤盐分含量反演状况,以黄河三角洲典型区域为研究区,获取地物高光谱和无人机多光谱两种数据源与样点土壤盐分含量,通过优选敏感光谱参量,使用偏最小二乘回归(Partial Least Squares Regression,PLSR)和随机森林(Random Forest,RF)两种机器学习算法建立土壤盐分含量反演模型,实现研究区的土壤盐分含量反演。结果表明:(1)高光谱1972 nm波段与土壤盐分含量间的敏感性最高,相关系数为-0.31。(2)两种不同数据源优化后的RF模型均优于PLSR,且稳定性更好。(3)基于地物高光谱的RF模型(R^(2)=0.54,RMSEv=3.30 g/kg)优于基于无人机多光谱的RF模型(R^(2)=0.54,验证RMSRv=3.35 g/kg)。(4)结合无人机影像采用多光谱RF模型对研究区耕地的土壤盐分含量进行反演,研究区总体以轻、中度盐渍化土壤为主,对作物的耕种具有一定程度的限制。本研究构建并对比了两种不同源数据的黄河三角洲土壤盐分反演模型,并结合各自数据源的优势进行优化,探索了地表无植被覆盖情况下的土壤盐分含量反演方法,对更精准反演土地盐渍化程度提供了参考。

关键词：土壤盐分含量遥感地物高光谱无人机多光谱偏最小二乘回归随机森林机器学习

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Timetabling optimization of classrooms and self-study rooms in university teaching buildings based on the building controls virtual test bed platform considering energy efficiency

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Building Simulation 2023年第2期16卷 263-277页

作者： Yanfeng Liu Hui Ming Xi luo Liang Hu yongkai Sun State Key Laboratory of Green Building in Western China Xi’an University of Architecture and TechnologyXi’an 710055China School of Building Services Science and Engineering Xi’an University of Architecture and TechnologyXi’an 710055China School of Management Xi’an University of Architecture and TechnologyXi’an 710055China

The energy consumption of a teaching building can be effectively reduced by timetable ***,in most studies that explore methods to reduce building energy consumption by course timetable optimization,self-study activities are not *** this study,an MATLAB-EnergyPlus joint simulation model was constructed based on the Building Controls Virtual Test Bed platform to reduce building energy consumption by optimizing the course schedule and opening strategy of self-study rooms in a holistic *** following results were obtained by taking a university in Xi’an as an example:(1)The energy saving percentages obtained by timetabling optimization during the heating season examination week,heating season non-examination week,cooling season examination week,and cooling season non-examination week are 35%,29.4%,13.4%,and 13.4%,respectively.(2)Regarding the temporal arrangement,most courses are scheduled in the morning during the cooling season and afternoon during the heating *** the spatial arrangement,most courses are arranged in the central section of the middle floors of the building.(3)During the heating season,the additional building energy consumption incurred by the opening of self-study rooms decreases when duty heating temperature increases.

关键词： timetabling optimization university teaching buildings energy efficiency Building Controls Virtual Test Bed platform genetic algorithm

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Facile Synthesis of Fe/Cr-Codoped ZnO Nanoparticles with Excellent Adsorption Performance for Various Pollutants

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Journal of Ocean University of China 2021年第2期20卷 349-360页

作者： SUN yongkai luo Siqi XING Jing LI Zhenjiang MENG Alan College of Electromechanical Engineering Qingdao University of Science and TechnologyQingdao 266061China Gaomi Campus Qingdao University of Science and TechnologyGaomi 266000China Key Laboratory of Sensor Analysis of Tumor Marker Ministry of EducationCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China

Adsorption is an effective and low-cost method for removing antibiotics and dyes. However, it remains a challenge to prepare an adsorbent with excellent adsorption properties for both various antibiotics and dyes. Herein, Fe/Cr-codoped ZnO with high adsorption capacity and fast adsorption rate are prepared by an environmentally friendly solvothermal method. Fe/Cr-codope ZnO with a diameter of 10–20 nm exhibits superior adsorption capacities for the antibiotics of tetracycline hydrochloride(TC-HCl)(826.45 mg g-1) and tetracycline(TC)(331.01 mg g-1), and anionic dyes of methyl orange(MO)(1023.88 mg g-1), methyl blue(MB)(726.26 mg g-1) and direct red(DR)(642.25 mg g-1). Meanwhile, it presents fast adsorption rate, it only took 30 min to reach more than 90% of the equilibrium adsorption amount for TC-HCl, TC, MO, MB and DR. The adsorption process closely fitted the Langmuir isotherm model and pseudo second-order rate equation. More importantly, simple method has been developed for separating the pollutant from the adsorbent, which not only regenerates the materials, but also completes the recovery of antibiotics and dyes, avoiding the secondary pollution. The broad-spectrum, rapid, environment-friendly and effective adsorption properties make Fe/Crcodoped ZnO a promising adsorbent for water treatments.

关键词： antibiotics dyes codoped adsorption regeneration

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