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Photosynthetic and water-related physiological characteristics of Periploca sepium in response to changing soil water conditions in a shell sand habitat

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Journal of Forestry Research 2023年第2期34卷 453-467页

作者： Xiao Wang Jiangbao Xia Ximei Zhao Mingming Dong Xianshuang Xing Ying Fang Qinqin Fu zhaohua lu Institute of Restoration Ecology School of Chemical and Environmental EngineeringChina University of Mining and Technology(Beijing)Beijing 100083People’s Republic of China Shandong Provincial Key Laboratory of Eco-Environmental Science for Yellow River Delta Binzhou UniversityBinzhou 256603People’s Republic of China Shandong Hydrology Center Jinan 250013People’s Republic of China

This study was performed to observe the effects of water on photosynthesis and water-related physiology in dominant shrubs in shell sand habitats.Four-year-old Periploca sepium seedlings were used as model species.A gradient of 12 water levels was established by artificially supplying the shell sand with water up to saturation and then allowing natural evapotranspiration to occur.The photo synthetic,chlorophyll fluorescence and stem sap flow parameters of P.sepium were measured under a range of water conditions.The different soil water conditions were classified according to the responses of these parameters.(1)With the increase in the relative water content(RWC)of the shell sand,the parameters of leaf photosynthesis,chlorophyll fluorescence and water-related physiology in P.sepium showed significant critical responses.The net photo synthetic rate(Pn),transpiration rate(Tr),instantaneous water use efficiency(WUE),potential water use efficiency(WUEi),maximum photochemical efficiency(Fv/Fm),actual photochemical efficiency(ΦPSII)and daily accumulation of stem sap flow all increased first and then decreased with increasing RWC,but the corresponding water conditions associated with their maximum values were not the same.An RWC of 69.40%was determined to be the optimal water condition for photosynthesis and water-related physiological activity in P.sepium.At an RWC of 36.61%,the mechanism of photosynthetic inhibition in P.sepium changed from stomatal limitation to nonstomatal limitation;this was also the minimum water requirement for maintaining normal photo synthetic processes.An RWC of 50.27%resulted in the highest WUE in P.sepium,indicating that moderate drought stress increased WUE.(2)Based on the quantitative relationship between the photo synthetic parameters of P.sepium and the shell sand water gradient,the soil water availability was classified into 6 water grades.The RWC range for maintaining strong photosynthesis and high WUE in P.sepium was 63.22-69.98%.(3)Gas exchange in P.sepium was inhibited under drought

关键词： Water gradient range Periploca sepium Photosynthesis Water physiology Water availability classifi cation Shell sand

Li(Sc,M)Si_(2)O_(6)∶Cr^(3+)(M=Ga^(3+)/lu^(3+)/Y^(3+)/Gd^(3+))的近红外发光性能

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发光学报 2024年第3期45卷 407-414页

作者：卢紫微刘永福罗朝华孙鹏蒋俊宁波大学材料科学与化学工程学院浙江宁波315211 中国科学院宁波材料技术与工程研究所浙江宁波315201

荧光转换型近红外发光二极管(NIR pc-LED)具有体积小、谱带宽、峰位易调谐等优点,是新一代NIR光源发展的前沿,其关键在于研发可被蓝光有效激发的高效率宽带近红外荧光粉。LiScSi_(2)O_(6)∶Cr^(3+)荧光材料的激发波长为460 nm,发射峰位... 详细信息

荧光转换型近红外发光二极管(NIR pc-LED)具有体积小、谱带宽、峰位易调谐等优点,是新一代NIR光源发展的前沿,其关键在于研发可被蓝光有效激发的高效率宽带近红外荧光粉。LiScSi_(2)O_(6)∶Cr^(3+)荧光材料的激发波长为460 nm,发射峰位在845 nm,光谱带宽为156 nm,内量子效率为64.4%。基于该体系,本文通过M离子(M=Ga^(3+),lu^(3+),Y^(3+),Gd^(3+))取代Sc^(3+)的方式对其性能进行调控。结果表明,引入M离子易生成杂相或发生相变,降低了材料的发光性能。本文从晶体结构出发对其调控过程进行了分析。

关键词： LiScSi_(2)O_(6)∶Cr^(3+) 阳离子取代晶体结构

Topsoil dichlorodiphenyltrichloroethane and polychlorinated biphenyl concentrations and sources along an urban-rural gradient in the Yellow River Delta

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Journal of Environmental Sciences 2012年第9期24卷 1655-1661页

作者： Wenjun Xie Aiping Chen Jianyong Li Qing Liu Hongjun Yang Tao Wu zhaohua lu Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta Binzhou University Binzhou 256603 China. Institute of Restoration Ecology China University of Mining and Technology Beijing 100083 China Jinan Entry-Exit Inspection and Quarantine Bureau Jinan 250000 China

The Yellow River Delta （YRD） is a typical agricultural and petrochemical industrial area of China. To assess the current status of soil dichlorodiphenyltrichloroethane （DDT） and polychlorinated biphenyls （PCB） residues, topsoil samples （0-15 cm）（n = 82） were collected in Bincheng District, at the geographic center of the YRD. The total concentrations of six DDT homologues were within 3.3-3819 ~tg/kg, with a mean concentration of 191 ~tg/kg, showing significant increase along urban-rural gradient. Soil concentrations of seven indicator PCBs in the area ranged from non-detectable to 87.0 ~g/kg, dominated by heavily chlorinated PCBs （PCB-101 and -118）. Soil PCBs concentrations were significantly greater in urban than suburban and rural areas. Principal component and multiple linear regression analysis suggest that 86.4% of soil DDTs originate from past DDT usage, and 13.6% originate from dicofol application. Soil PCBs most likely originate from the petrochemical industry （77.1%）, municipal solid waste disposal （16.5%）, local commercial PCB homologues usage （5.2%）, and long-range atmospheric deposition （1.2%）. In general, soil DDTs pollution was classified as low level, and mean PCBs concentrations were below the severe contamination classification range. Because PCB-118 is a dioxin-like congener, monitoring and remediation is advised to assess and reduce negative environmental and human health effects from soil DDTs and dioxin-like congeners in the study area.

关键词： DDTs PCBs Yellow River Delta source apportionment risk assessment

Cloning and expression analysis of the FvNCED3 gene and its promoter from ash(Fraxinus velutina)

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Journal of Forestry Research 2019年第2期30卷 471-482页

作者： Tian Li Jingkuan Sun Chuanrong Li zhaohua lu Jiangbao Xia Shandong Provincial Key Laboratory of Eco-Environmental Science for Yellow River Delta Binzhou University Taishan Forest Ecosystem Research Station/Shandong Provincial Key Laboratory of Soil Erosion and Ecological Restoration

The 9-cis-epoxycarotenoid dioxygenase(NCED)gene is rate-limiting in abscisic acid(ABA) biosynthesis.In this study, an NCED gene, designated FvNCED3(KY008746), was cloned from velvet ash(Fraxinus velutina Torr.) with a RACE method. The full length c DNA of FvNCED3 encodes a 573-amino acid polypeptide.Sequencing analysis showed that the FvNCED3 protein was highly homologous to other NCED proteins. The expression patterns of FvNCED3 in different ash organs were analyzed by real-time PCR which revealed that FvNCED3 expression levels were highest in leaves and lowest in roots. The gene expression patterns of FvNCED3 under abiotic stress indicated that its expression increased under drought, salt and ABA stress and decreased due to high and low temperatures. There were no obvious changes under ultraviolet light. The 1094-bp upstream sequence 5' flank regulation region of the FvNCED3 gene was also cloned from ash using the Genome Walking method. To assess the activity of the FvNCED3 promoter, a p FvNCED3 p::GUS plant expression vector was constructed for tobacco transformation. GUS expression of the FvNCED3 GUS enzyme activity was detected in almost all transgenic tobacco tissues, especially in the young leaves,stigma, anther, ovule and ovary. After treating the transgenic tobacco with NaCl and placing it under drought stress, GUS staining of tobacco leaves increased compared with that under normal growth conditions. This result indicates that gene expression driven by the FvNCED3 promoter can be induced by salt and drought stress.

关键词： Ash Function analysis NCED gene Promoter Tobacco

Effect of organic materials on the chemical properties of saline soil in the Yellow River Delta of China

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Frontiers of Earth Science 2015年第2期9卷 259-267页

作者： Yan YU Jie LIU Chunmeng LIU Shuang ZONG zhaohua lu School of Chemical and Environmental Engineering China University of Mining and Technology (Beijing) Beijing 100083 China Transport Planning and Research Institute Ministry of Transport Beijing 100028 China

A 180-day incubation experiment was con- ducted to investigate the effect of different organic materials on the chemical properties of coastal soil with high salinity and relatively low pH. Four organic materials （three kinds of plant residues： straw, composted straw, and fresh reed; and one kind of poultry manure： chicken manure） were applied at a ratio of 15 g·kg^-1 to samples of costal saline soil from the Yellow River Delta of China. The results showed that the soil pH and exchangeable sodium percentage （ESP） decreased, whereas soil cation exchangeable capacity （CEC） and macronutrient concen- trations increased, regardless of the type of organic material used. All treatments showed a remarkable increase in soil soluble organic carbon （SOC） during the 180-day incubation. The peak values of SOC in descend- ing order were chicken manure, reed, composted straw, straw, and control soil. At the end of incubation, the highest level of SOC occurred in the straw-amended soil, followed by composted straw, reed, and chicken manure- amended soils. Soil respiration rate and available nitrogen were significantly influenced by the type of material used. Although reed-amended soil had a relatively high SOC and respiration rate, the ESP was reduced the least. Consider- ing the possible risk of heavy metals caused by chicken manure, it is proposed that straw and composted straw are the more efficient materials to use for reclaiming costal saline soil and improving the availability of macronu- trients.

关键词： organic material soil organic carbon salt-affected soil ESP respiration rate

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公诉案件和解自愿性审查规则的重构进路

黑龙江工业学院学报（综合版） 2024年第3期24卷 49-54页

作者：闫召华李璐西南政法大学法学院重庆401120

自愿性是刑事和解制度适用的基础与前提。当前,刑事和解自愿性的审查实践中出现审查内容存在模糊性、审查方式浮于表面、和解协议书之法律性质不明晰、律师参与不足等问题。构建刑事和解自愿性的审查模式应坚持公正优先、兼顾效率的立场... 详细信息

自愿性是刑事和解制度适用的基础与前提。当前,刑事和解自愿性的审查实践中出现审查内容存在模糊性、审查方式浮于表面、和解协议书之法律性质不明晰、律师参与不足等问题。构建刑事和解自愿性的审查模式应坚持公正优先、兼顾效率的立场,明确刑事和解协议兼具公法契约与书证之法律属性;构建以形式审查为原则、以实质审查为补充的刑事和解自愿性审查机制。

关键词：和解自愿性审查机制证据契约正当程序证据印证

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Genetic variation in growth traits and stem–branch characteristics and their relationships to Eucalyptus clones

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Journal of Forestry Research 2015年第4期26卷 957-962页

作者： Shijun Wu zhaohua lu Jianmin Xu Guangchao Chen Yingan Zhu Guangyou Li Research Institute of Tropical Forestry Chinese Academy of Forestry

Eucalyptus has become an important genus in China because it displays adaptability to a wide range of site conditions and produces pulp wood and veneer on short rotations. The aim of this study was to estimate genetic parameters and relationships and consider impli- cations for development of clonal forestry. We assessed growth traits, stem-branch characteristics, crown diameter and height of fresh branch for 20 Eucalyptus hybrid clones in China measured at the age of 44 months. Analysis of variance showed that there were significant differences in growth traits, height of fresh branch and stem straightness among clones. Significant differences in height, volume, crown diameter, height of fresh branch and branch size among replicates were also recorded. Coefficients of vari- ation ranged from 9.84 to 28.54 % for growth traits, 12.03 to 17.25 % for stem-branch characteristics, 18.26 % for crown diameter and 11.73 % for height of fresh branch. Estimates of repeatabilities for height, diameter at breastheight over bark, volume, crown diameter, height of fresh branch, stem straightness and branch size at clone mean level were 0.86, 0.80, 0.80, 0.54, 0.85, 0.77 and 0.44 respectively. Diameter at breast height over bark and height had strongly positive phenotypic and genotypic correlations with volume, ranging from 0.96 to 1.00. The positive genotypic and phenotypic correlations between growth traits and other studied traits suggested that fast growing clones always had bigger crown diameter, higher height of fresh branch, straighter stems and relatively smaller branches.

关键词： Multiple comparison Clonal variation Genotypic and phenotypic correlations Eucalyptus clones

Vegetation pattern in Shell Ridge Island in China＇s Yellow River Delta

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Frontiers of Earth Science 2015年第3期9卷 567-577页

作者： Yanyun ZHAO Xiangming HU Jingtao LIU zhaohua lu Jiangbao XIA Jiayi TIAN JunshengMA Institute of Restoration Ecology School of Chemical & Environmental Engineering China University of Mining & Technology (Beijing) Beijing 100083 China Shandong Provincial Key Laboratory of Eco-Environmental Science for Yellow River Delta Binzhou University Binzhou 256603 China Department of Resources & Environmental Engineering Binzhou University Binzhou 256603 China Administrative Bureau of Binzhou Shell Dyke Island and Wetland National Reserve Binzhou 251900 China

In general, coastal habitat conditions are extremely harsh, with the ecological equilibrium inextric- ably related to the plant community. Understanding the natural vegetation features of a coastal zone with little human disturbance could provide a reference for future vegetation restoration and ecosystem maintenance ser- vices. In this study, the vegetation patterns of Wangzi Shell Ridge Island in the Yellow River Delta were investigated. A total of 35 taxa of vascular plants were documented, representing 15 families and 33 genera （of which most were mono-specific）. Surveys identified only one to eight taxa in each plot. From sea to land, the vegetation showed a typical zonal distribution pattern. There was a correlation between the landform and important factors that influenced the plants including soil factors and distance from the sea. Thus, the taxa distribution and vegetation had a significant correlation with landform. The dune crest, backdune and interdune lowlands were areas with weak storm surges and were the important locations for the taxa to be become established. Plants along the high-tide line formed important defenses from large waves and high winds. The significant protection provided a suitable living environment for many organisms with high medicinal value. Special attention and protection could be provided to this area by reducing the use of the beach road and enclosing the complete section from sea to land with a protective fence. In addition, vegetation protection and restoration on Shell Ridge Island would aid in the formulation and implementation of reintroduction strate- gies for similar vegetation in similar habitats.

关键词： wetland vegetation diversity landform zonaldistribution conservation value

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面向6G的信道状态信息压缩技术

中兴通讯技术 2024年第3期30卷 60-66页

作者：鲁照华胡留军李伦李永中兴通讯股份有限公司中国深圳518057 移动网络和移动多媒体技术全国重点实验室中国深圳518055

提出基于人工智能的信道状态信息压缩技术方案,并全面思考了模型训练、模型管理中的标准制定、实际应用等相关问题,分析了不同问题的潜在解决方案。仿真结果表明,所提出的方案可有效提升信道状态信息反馈精度,网络容量平均提升10%左右。

关键词：人工智能多输入多输出信道状态信息