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A Germplasm Resource Repository:The Book Review of Illustrated Flora of Food Crops and Their Wild Related Plants in China
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作者 Yuting CHEN 《Asian Agricultural Research》 2024年第7期59-60,共2页
Illustrated Flora of Food Crops and Their Wild Related Plants in China systematically examines the botanical and morphological characteristics of China's major food crops,such as rice,wheat,corn,sweet potato,potat... Illustrated Flora of Food Crops and Their Wild Related Plants in China systematically examines the botanical and morphological characteristics of China's major food crops,such as rice,wheat,corn,sweet potato,potato,mung bean,and buckwheat.Featuring more than 5000 color photos and 200 line drawings,it offers a comparative study that highlights the kinship and internal connections between cultivated and wild species.The book is an invaluable resource for breeders,offering a comprehensive morphological and genetic database that aids in the development of high-yielding,high-quality,and disease-resistant crop varieties. 展开更多
关键词 Food security Crop improvement Wild relatives Breeding resource plant illustrations
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Crown Ratio and Relative Spacing Relationships for Loblolly Pine Plantations 被引量:2
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作者 Dehai Zhao Michael Kane Bruce E. Borders 《Open Journal of Forestry》 2012年第3期101-115,共15页
Two loblolly pine (Pinus taeda L.) culture/density studies were established in 1995-1998 across the Lower Coastal Plain and Upper Coastal Plain/Piedmont regions of the southern USA. Each installation contains 12 plots... Two loblolly pine (Pinus taeda L.) culture/density studies were established in 1995-1998 across the Lower Coastal Plain and Upper Coastal Plain/Piedmont regions of the southern USA. Each installation contains 12 plots of loblolly pine planted at six levels of density from 741 to 4448 trees/ha in combination with two levels of cultural intensity, operational and intensive. The data from 37 viable installations were used to evaluate the crown ratio and relative spacing relationship of loblolly pine plantations. The effects of planting density, site quality, and cultural intensity on the relationship were investigated with a nonlinear mixed-effects modeling approach. The crown ratio and relative spacing relationship is exceedingly predictable. When loblolly pine plantation stands reached the average live crown ratio of 0.40, a critical point representing a generally acceptable level of tree vigor, the corresponding relative spacing index ranged from 0.11 to 0.20, mainly depending on initial planting density. The information about the crown ratio and relative spacing relationship would be useful for selecting the best intensity and timing of thinning. 展开更多
关键词 Loblolly PINE INTENSIVE Culture plantING Density Live CROWN RATIO relative SPACING Index
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Relative sensitivities of woody plants to acid deposition in south areas of China 被引量:1
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作者 Feng Zongwei and Shan YunfengResearch Center for Eco-Environmental Sciences,Academia Sinica,Beijing 100083,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1991年第2期61-68,共8页
Relative sensitivities of 30 species of common woody plants to simulated acid rain with pH values of 2.0, 2.5, 3.0, 3.5, 4.5 and control were studied. The results showed that 6 species of these plants were sensitive t... Relative sensitivities of 30 species of common woody plants to simulated acid rain with pH values of 2.0, 2.5, 3.0, 3.5, 4.5 and control were studied. The results showed that 6 species of these plants were sensitive to simulated acid rain. The moderate included 18 species. The resistant included 6. Relative sensitivities to ambient acid rain and air pollutants and visible injury degree of 30 species of common woody plants in Chongqing City were investigated. Results showed that 6 species with foliage lesion rate at above 10 percent were sensitive, that 6 species with no lesion were resistant and that other 18 species with lesion at 10 percent below were moderate. Other 7 cities (Guiyang, Zunyi, Duyun, Changsha, Zhuzhou, Liuzhou and Guilin City) were also investigated and results were consistent with those of Chongqing City. The experimental and investigated results showed relative sensitivities and visible injury degree of woody plants to simulated acid rain were consistent with those of the woody plants to ambient acid rain and air pollutants. The sensitive plants may be used as bioindicators to acid rain or air pollutants. The resistant species can be introduced to acid rain and air pollution areas to substitute damaged sensitive plants in order to improve environment. 展开更多
关键词 relative sensitivity acid rain woody plant.
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Pathogenesis-related protein genes involved in race-specific allstage resistance and non-race specific high-temperature adultplant resistance to Puccinia striiformis f. sp. tritici in wheat 被引量:5
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作者 Sumaira Farrakh Meinan Wang Xianming Chen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第11期2478-2491,共14页
Interactions of the stripe rust pathogen (Puccinia striiformis f. sp responses. Among various genes involved in the plant-pathogen related (PR) protein genes determine different defense responses tritici) with wh... Interactions of the stripe rust pathogen (Puccinia striiformis f. sp responses. Among various genes involved in the plant-pathogen related (PR) protein genes determine different defense responses tritici) with wheat plants activate a w^ae range OT nost nteractions, the expressions of particular pathogenesis-Different types of resistance have been recognized and utilized for developing wheat cultivars for resistance to stripe rust. All-stage resistance can be detected in seedling stage and remains at high levels throughout the plant growth stages. This type of resistance is race-specific and not durable. In contrast, plants with only high-temperature adult-plant (HTAP) resistance are susceptible in seedling stage, but become resistant when plants grow older and the weather becomes warmer. HTAP resistance controlled by a single gene is partial, but usually non-race specific and durable. The objective of this study was to analyze the expression of PR protein genes involved in different types of wheat resistance to stripe rust. The expression levels of 8 PR protein genes (PR1, PRI.2, PR2, PR3, PR4, PR5, PR9 and PRIO) were quantitatively evaluated at 0, 1, 2, 7 and 14 days after inoculation in single resistance gene lines of wheat with all-stage resistance genes YrTrl, Yr76, YrSP and YrExp2 and lines carrying HTAP resistance genes Yr52, Yr59, Yr62 and Yr7B. Races PSTv-4 and PSTv-37 for compatible and incompatible interactions were used in evaluation of PR protein gene expression in wheat lines carrying all-stage resistance genes in the seedling- stage experiment while PSTv-37 was used in the HTAP experiment. Analysis of quantitative real-time polymerase chain reaction (qRT-PCR) revealed that all of the PR protein genes were involved in the different types of resistance controlled by different Yr genes. However, these genes were upregulated at different time points and at different levels during the infection process among the wheat lines with different Yr genes for either all-stage resistance or HTAP resistance. Some of the genes were also induced in compatible interactions, but the levels were almost always higher in the incompatible interaction than in the compatible interaction at the same time point for each Yr gene. These results indicate that both salicylic acid and jasmonate signaling pathways are involved in both race-specific all-stage resistance and non-race specific HTAP resistance. Although expressing at different stages of infection and at different levels, these PR protein genes work in concert for contribution to different types of resistance controlled by different Yr genes. 展开更多
关键词 WHEAT stripe rust plant resistance pathogen-related protein QRT-PCR
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Herbivory and Plant Genotype Influence Fitness-Related Responses of<i>Arabidopsis thaliana</i>to Indirect Plant-Plant Interactions
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作者 Jennifer Shimola M. Gabriela Bidart 《American Journal of Plant Sciences》 2019年第8期1287-1299,共13页
Previous studies have demonstrated that genetic identity between interacting perennial plants results in more effective defense when emitter and receiver neighbors have greater genetic similarity. However, the effects... Previous studies have demonstrated that genetic identity between interacting perennial plants results in more effective defense when emitter and receiver neighbors have greater genetic similarity. However, the effects of both genetic relatedness and presence of herbivores on fitness-related responses of neighboring plants have not yet been explored. Our aim was to examine how manipulating these two important factors genetic and environmental factors can influence indirect plant-plant communication in the annual crucifer Arabidopsis thaliana. Plants of a single genotype (receivers) were exposed to volatile emissions of neighboring emitter plants with a similar or different genotype, and either intact or damaged by larvae of a specialist herbivore for ten days. Each of the four treatments was isolated in separate environmental chambers and the full experiment was replicated twice. Receiver plant growth and reproductive-related traits were measured ten days after exposure to treatments, and at senescence. Results showed that the effect of herbivory and plant genotype of emitter plants influenced responses related growth and reproduction in receiver plants. Receiver plants grew taller, had more inflorescence branching, and produced more fruits (60% more) when exposed to undamaged emitters of a different genotype than receivers exposed to the other emitter plant treatments. Therefore, genotype identity and environmental context (presence of herbivory) may be important factors influencing indirect plant-plant communication, which could, in turn, result in selection for genotypes showing increased fitness-related responses. 展开更多
关键词 plant-plant Interactions plant Genotype Insect HERBIVORY Fitness-related RESPONSES
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Deep learning-based intelligent management for sewage treatment plants 被引量:2
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作者 WAN Ke-yi DU Bo-xin +5 位作者 WANG Jian-hui GUO Zhi-wei FENG Dong GAO Xu SHEN Yu YU Ke-ping 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第5期1537-1552,共16页
It is generally believed that intelligent management for sewage treatment plants(STPs) is essential to the sustainable engineering of future smart cities.The core of management lies in the precise prediction of daily ... It is generally believed that intelligent management for sewage treatment plants(STPs) is essential to the sustainable engineering of future smart cities.The core of management lies in the precise prediction of daily volumes of sewage.The generation of sewage is the result of multiple factors from the whole social system.Characterized by strong process abstraction ability,data mining techniques have been viewed as promising prediction methods to realize intelligent STP management.However,existing data mining-based methods for this purpose just focus on a single factor such as an economical or meteorological factor and ignore their collaborative effects.To address this challenge,a deep learning-based intelligent management mechanism for STPs is proposed,to predict business volume.Specifically,the grey relation algorithm(GRA) and gated recursive unit network(GRU) are combined into a prediction model(GRAGRU).The GRA is utilized to select the factors that have a significant impact on the sewage business volume,and the GRU is set up to output the prediction results.We conducted a large number of experiments to verify the efficiency of the proposed GRA-GRU model. 展开更多
关键词 deep learning intelligent management sewage treatment plants grey relation algorithm gated recursive unit
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Protease Inhibitors in Wild Relatives of Pigeonpea against the Cotton Bollworm/Legume Pod Borer, <i>Helicoverpa armigera</i> 被引量:1
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作者 Vinod D. Parde Hari C. Sharma Manvendra S. Kachole 《American Journal of Plant Sciences》 2012年第5期627-635,共9页
Cotton bollworm/legume pod borer, Helicoverpa armigera is one of the most damaging pests worldwide. Be-cause of the difficulties associated with chemical control of this pest, emphasis has been placed on developing tr... Cotton bollworm/legume pod borer, Helicoverpa armigera is one of the most damaging pests worldwide. Be-cause of the difficulties associated with chemical control of this pest, emphasis has been placed on developing transgenic plants with resistance to H. armigera. Since toxin genes from the bacterium, Bacillus thuringien-sis (Bt) have been deployed on a large scale, there is need to scout for alternate genes which could be deployed alone or in combination with the Bt genes for pest management. Therefore, we evaluated the wild relatives of pigeonpea, which have shown high levels of resistance to this pest, for the protease inhibitors (PIs) under in vivo and in vitro inhibitions. Accessions belonging to Cajanus albicans, C. cajanifolius, C. sericeus, Flemingia bracteata, and Rhynchosia bracteata showed complete inhibition of H. armigera gut proteinases (HaGPs). Some of the C. scarabaeoides accessions (ICPW 116, 152, 278 and 280) exhibited partial inhibition at low concentrations of the PIs. All accessions of wild relatives of pigeonpea showed high to moderate level of inhibition at pH 7.8. Cultivated pigeonpea, ICPL 87 exhibited monomorphism in terms of trypsin inhibitor (TI) and chymotrypsin inhibitor (CTI) isoforms, contrary to the diverse inhibitory profiles of wild pigeonpeas. Cajanus albicans, C. platycarpus, C. scarabaeoides, and R. bracteata showed more number of TI and CTI bands than the cultivated pigeonpea. Protease inhibitor isoforms of wild relatives of pigeonpea showed significant variation in number, band pattern, and protein specificities towards trypsin, chymotrypsin, and H. armigera gut proteinases (HaGPs) as compared to the cultivated pigeonpea. The PIs from the wild relatives of pigeonpea showed considerable potential against the HaGPs, and could be considered as potential candidates for use in genetic transformation of crops for pest management, including H. armigera. 展开更多
关键词 Wild relatives PIGEONPEA Protease Inhibitors HELICOVERPA ARMIGERA Transgenic plants Pest Management
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Investigation of the Effects of Radio Frequency Water Treatment on Some Characteristics of Growth in Pepper (<i>Capsicum annuum</i>) Plants
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作者 Etimad Alattar Eqbal Radwan 《Advances in Bioscience and Biotechnology》 2020年第2期22-48,共27页
The aim of the present study was to investigate the effect of electromagnetic radio frequency treatment of water on the growth of pepper (Capsicum annuum) plants. For this experiment, one hundred one-week old plants w... The aim of the present study was to investigate the effect of electromagnetic radio frequency treatment of water on the growth of pepper (Capsicum annuum) plants. For this experiment, one hundred one-week old plants were divided into two groups. The first group of plants was watered with water subjected to radio frequency electromagnetic radiation from an internet router for one hour a day, while the other group was watered with tap water (control). The overall results showed changes of growth characters of plant watered with electromagnetic water. The length of pepper plants is significantly affected by the treated water, where the length of shoot was lower in plants grown under the effect of treated water (22.43 ± 7.17 cm) than those grown without treated water (28.11 ± 8.57 cm). The results revealed that the stem diameter of control plants (1.74 ± 0.39 cm) was significantly higher than that of the treated plants (1.66 ± 0.35 cm). In addition, the root length was lower in plants grown under the effect of treated water than those grown without treated water. Pepper plants watered with electromagnetic treated water exhibited marked decreases in health index, fresh and dry weight, relative water content, number of flowers and fruits/plant as well as number of seeds/fruit. In addition, the current experiment showed a significant decrease in the number of leaves, branch and flower per plant when watered with electromagnetic treated water. The results revealed that the first flowering time for plants in treated group was remarkably decelerated when compared to other plants in control group. 展开更多
关键词 ELECTROMAGNETIC Spectrum Radiation ELECTROMAGNETIC Water Treatment GROWTH related CHARACTERISTICS PEPPER (Capsicum annuum) plantS
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Proteomics: A Successful Approach to Understand the Molecular Mechanism of Plant-Pathogen Interaction 被引量:1
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作者 Tushar Dilipchand Lodha Padmalochan Hembram Nitile Tep, Jolly Basak 《American Journal of Plant Sciences》 2013年第6期1212-1226,共15页
In recent years, proteomics has played a key role in identifying changes in protein levels in plant hosts upon infection by pathogenic organisms and in characterizing cellular and extracellular virulence and pathogeni... In recent years, proteomics has played a key role in identifying changes in protein levels in plant hosts upon infection by pathogenic organisms and in characterizing cellular and extracellular virulence and pathogenicity factors produced by pathogens. Proteomics offers a constantly evolving set of novel techniques to study all aspects of protein structure and function. Proteomics aims to find out the identity and amount of each and every protein present in a cell and actual function mediating specific cellular processes. Structural proteomics elucidates the development and application of experimental approaches to define the primary, secondary and tertiary structures of proteins, while functional proteomics refers to the development and application of global (proteome wide or system-wide) experimental approaches to assess protein function. A detail understanding of plant defense response using successful combination of proteomic techniques and other high throughput techniques of cell biology, biochemistry as well as genomics is needed for practical application to secure and stabilize yield of many crop plants. This review starts with a brief introduction to gel- and non gel-based proteomic techniques followed by the basics of plant-pathogen interaction, the use of proteomics in recent pasts to decipher the mysteries of plant-pathogen interaction, and ends with the future prospects of this technology. 展开更多
关键词 PROTEOME plant-PATHOGEN Interaction Systemic ACQUIRED Resistance Mass Spectrometry PATHOGENICITY related Proteins
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Atmospheric Dispersion Modeling of the Emissions from the Logbaba Thermal Power Plant, Douala-Cameroon
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作者 R. Mbiaké E. Mfoumou +4 位作者 A. Beya Wakata E. Ndjeuna J. R. Kaze Djamen R. Leduc C. Bobda 《Open Journal of Air Pollution》 2017年第4期117-134,共18页
Air quality in the vicinity of the thermal power plant of Logbaba in the town of Douala was investigated in this study using data collected in a 5-year period (2008-2012). The distribution of pollutants such as SO2, N... Air quality in the vicinity of the thermal power plant of Logbaba in the town of Douala was investigated in this study using data collected in a 5-year period (2008-2012). The distribution of pollutants such as SO2, NOx, CO and the particle matter PM2.5 was analyzed using numerical modeling, based on physical and thermal characteristics, as well as the operating periods of the power plant. The American Environmental Regulator Model (AERMOD) that is an atmospheric dispersion model was used for simulation. The wind rose and others National Oceanic Atmospheric Administration (NOAA) in-situ data were used for the validation of the model. The pollutants distribution was evaluated at two locations: the exit of the power plant, considered as reference point, and at 330 m away from the exit where the first houses appeared. The results show that the relative concentration for each contaminant at the exit of the power plant is 7.2% for the PM2.5 during 24 hours of emission, 46.0% for CO over 8 hours of emission, and 17.5% for SO2 over one hour. The NOx is the highest pollutant with 259.1% over an hour of emission and 51.0% over one year. Beyond 330 m of the power plant, only NOx keeps a polluting character with a relative rate of 100%. These results show that the pollution level of the power plant is over the threshold for air quality set by the World Health Organization. Moreover, among all pollutants investigated, NOx appears to be the most critical for the population in the vicinity of the Logbaba thermal power plant. This information is therefore important for policy and decision makers in preventing the vulnerability of the population to air pollutants from such industrial settings. 展开更多
关键词 AERMOD POLLUTANTS Air Quality Model relatIVE CONCENTRATION Thermal Power plant
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Lack of Evidence for Local Adaptation of the Endangered Karner Blue Butterfly to Its Sole Larval Hostplant—The Wild Lupine
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作者 Kevin Handel Maria Gabriela Bidart 《Advances in Entomology》 2023年第3期172-187,共16页
Local adaptation is an important process that drives the evolution of populations within species, and it can be generally expressed by the higher fitness of individuals raised in their native habitats versus in a fore... Local adaptation is an important process that drives the evolution of populations within species, and it can be generally expressed by the higher fitness of individuals raised in their native habitats versus in a foreign location. The influence of local adaptation is especially prominent in species that subsist in small and/or highly isolated populations. This study evaluated whether the federally endangered Karner blue butterfly, Lycaeides melissa samuelis (Lepidoptera: Lycaenidae) is locally adapted to its exclusive larval host plant, the wild lupine (Lupinus perennis). To test for local adaptation, individuals from a laboratory-raised colony were reared on wild lupine plants from populations belonging to either their native (Indiana) or a foreign (Michigan and Wisconsin) region. For this purpose, lupine plants from the different populations were grown in a common garden in growth chambers, and one Karner blue larva was placed on each plant. Fitness traits related to growth and development were recorded for each butterfly across populations. Days from hatching to pupation and eclosion showed gender-specific significant differences across wild lupine populations and plant genotypes (within populations). The percent survival of butterflies (from hatching to eclosion) also differed among plants from different populations. These results indicate that wild lupine sources can affect some developmental traits of Karner blue butterflies. However, growth-related traits, such as pupal and adult weight of individuals reared in plants from native populations did not differ from those of foreign regions. The apparent absence of local adaptation to wild lupine suggests that, at least, some individuals of this species could be translocated from native populations to foreign reintroduction sites without experiencing decreased fitness levels. However, future studies including more populations across the geographical range of this butterfly are recommended to evaluate other environmental factors that could influence adaptation on a wider spatial scale. 展开更多
关键词 Local Adaptation Karner Blue Butterfly Wild Lupine Butterfly Fitness-related Responses plant Genotypic Effects
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凉水塔变形监测与基坑敏感因子灰色关联分析
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作者 栾亨宣 许浩 +4 位作者 郭传超 田志超 左世晓 胡军伟 栾元重 《工程勘察》 2024年第9期50-54,88,共6页
基坑开挖容易引起临近电厂凉水塔变形,是深基坑工程面临的主要难题之一。本文实地监测深基坑开挖对附近电厂凉水塔的影响,统计了基坑开挖过程中凉水塔地表垂直和水平位移、结构变形等参数。依托某实际工程,研究基坑开挖引起凉水塔变形... 基坑开挖容易引起临近电厂凉水塔变形,是深基坑工程面临的主要难题之一。本文实地监测深基坑开挖对附近电厂凉水塔的影响,统计了基坑开挖过程中凉水塔地表垂直和水平位移、结构变形等参数。依托某实际工程,研究基坑开挖引起凉水塔变形预测方法,建立凉水塔地表垂直位移灰色预测模型。采用灰色关联分析确定基坑各敏感因素对凉水塔变形的影响程度,由大到小依次为:基坑与建筑物间距、土体弹性模量、围护结构厚度、土体内摩擦角、土体粘聚力。通过开展凉水塔变形监测与相关研究工作,相关研究理论能够为类似深基坑工程提供参考。 展开更多
关键词 基坑 电厂凉水塔 监测 预测 灰色关联分析
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种植方式对工业大麻产量相关性状的影响
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作者 李洪超 李紫薇 +2 位作者 崔鹤露 蔡萌萌 王晓楠 《现代农业科技》 2024年第20期28-31,48,共5页
不同用途的工业大麻种植方式不同,种植方式的不同可以体现在种植密度上。为此,利用相关性分析和主成分分析等方法,对3个工业大麻品种在2种种植方式下的10个产量相关性状进行分析。结果表明:种植方式与株高、茎粗、节数、鲜茎重和干茎重... 不同用途的工业大麻种植方式不同,种植方式的不同可以体现在种植密度上。为此,利用相关性分析和主成分分析等方法,对3个工业大麻品种在2种种植方式下的10个产量相关性状进行分析。结果表明:种植方式与株高、茎粗、节数、鲜茎重和干茎重成极显著负相关,与干皮重成显著负相关,与节间长成显著正相关;产量相关性状的主成分分析提取到2个主成分,累计贡献率为86.043%,从中筛选到4个产量关键性状;引进资源和汉麻10号适宜籽纤兼用种植方式(250粒/m^(2),行距30 cm),汉麻12号适宜纤维用种植方式(450粒/m^(2),行距15 cm)。 展开更多
关键词 工业大麻 种植方式 产量相关性状 相关性分析 主成分分析
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基于OBE理念的涉农类课程混合式教学模式改革探究
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作者 欧阳秋飞 韦兰洁 +1 位作者 李荣峰 李曦 《安徽农学通报》 2024年第21期112-115,共4页
本文从教学目标与内容、教学模式和教学评价体系3个方面入手,对地方应用型高校涉农类课程教学现状进行分析。基于OBE教学理念,采用线上线下混合式教学模式,以园艺植物病理学课程为例,通过重构教学目标与内容框架,结合“线上+线下”重构... 本文从教学目标与内容、教学模式和教学评价体系3个方面入手,对地方应用型高校涉农类课程教学现状进行分析。基于OBE教学理念,采用线上线下混合式教学模式,以园艺植物病理学课程为例,通过重构教学目标与内容框架,结合“线上+线下”重构教学过程,以及优化教学考核评价体系,对地方应用型高校涉农类课程教学改革进行探索研究。实践教学成效表明,改革后的教学模式增强了学生学习的主动性和自主学习能力,激发了其学习兴趣,教学满意度达94%。本研究为提高地方应用型高校涉农类课程教学质量,加强课程建设提供参考。 展开更多
关键词 园艺植物病理学 OBE理念 地方应用型高校 涉农类课程 混合式教学
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矿区排土场植物多样性及其与土壤理化指标的耦合关系
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作者 马媛 张景波 +5 位作者 蔺方春 辛智鸣 罗凤敏 杨耀科 郭俊廷 王嘉鹏 《林草资源研究》 北大核心 2024年第2期51-58,共8页
探究鄂尔多斯满来梁矿区不同修复年限下植物多样性及其与土壤理化指标的耦合关系,揭示植被与土壤在生态修复中的相互作用,为优化植被恢复策略及评估修复效果提供科学依据。以修复年限在2~12 a的植被与土壤理化指标为研究对象,原始地貌... 探究鄂尔多斯满来梁矿区不同修复年限下植物多样性及其与土壤理化指标的耦合关系,揭示植被与土壤在生态修复中的相互作用,为优化植被恢复策略及评估修复效果提供科学依据。以修复年限在2~12 a的植被与土壤理化指标为研究对象,原始地貌为对照,通过调查不同样地内的植被组成与土壤理化性质,利用相关性分析揭示其相互影响与作用方式。结果表明:1)研究区共调查到51种植物,以菊科、禾本科和豆科为主,三者共占植物种类总数的61%;2)植物多样性随时间变化显著,物种数量先减少后增加,Margalef和Shannon-Weiner指数先降后升,Pielou和Simpson指数无明显变化;3)植物多样性指数与土壤理化指标存在中度及以上关联,其中pH和全磷与物种多样性关联较密切;4)修复初期,植物多样性与土壤理化指标的协调度提高,随修复年限增加,协调度先升高再降低,修复6 a时协调度最高。修复措施对植物多样性及其土壤理化指标的平衡发展有积极作用,需不断优化修复措施,使之达到最佳协调水平。 展开更多
关键词 矿区排土场 植物多样性 灰色关联度分析 耦合分析
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基于特征优选和机器学习组合模型的锅炉受热面壁温预测 被引量:1
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作者 祁浩浩 茅大钧 陈思勤 《电力科学与工程》 2024年第2期71-78,共8页
为及时有效预测锅炉壁温的变化趋势,以某火电厂600 MW的1号机组高温再热器为例,提出一种融合特征筛选和极端梯度树(Extreme gradient boosting,XGboost)组合自适应增强算法(Adaptive boosting,Adaboost)模型。首先,利用灰色关联分析法... 为及时有效预测锅炉壁温的变化趋势,以某火电厂600 MW的1号机组高温再热器为例,提出一种融合特征筛选和极端梯度树(Extreme gradient boosting,XGboost)组合自适应增强算法(Adaptive boosting,Adaboost)模型。首先,利用灰色关联分析法和随机森林特征重要度分析法分别计算锅炉大量的历史运行数据与高再壁温之间的线性和非线性关联度,然后进行综合特征排序。在特征优选的基础上,利用建立的XGboost-Adaboost组合模型进行锅炉高再壁温的预测。结合真实运行数据的实验结果表明,该预测模型的平均相对误差和均方根误差分别为0.18%和1.34℃,预测的精度高于几种相关类型高再壁温的预测方法。 展开更多
关键词 燃煤电站 高温再热器 温度预测 灰色关联分析 随机森林 XGboost ADABOOST
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模拟事故工况下非能动核电厂安全相关涂层的可靠性测试及评估方法研究
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作者 李菲菲 刘晓强 孟凡江 《涂料工业》 CAS CSCD 北大核心 2024年第1期54-58,共5页
安全相关涂层在非能动核电厂中起着重要的作用,涂层的失效会影响核电厂安全系统的功能执行,影响核安全。国内外核监管机构对于在设计基准事故(DBA)工况下涂层系统的可靠性及评估方法非常重视。文章结合非能动核电厂涂层系统的工程应用,... 安全相关涂层在非能动核电厂中起着重要的作用,涂层的失效会影响核电厂安全系统的功能执行,影响核安全。国内外核监管机构对于在设计基准事故(DBA)工况下涂层系统的可靠性及评估方法非常重视。文章结合非能动核电厂涂层系统的工程应用,针对其在DBA下的可靠性及评估方法进行了研究。研究表明:在DBA下非能动核电厂安全相关涂层的可靠性要综合考虑涂层的模拟DBA性能、干膜密度、导热性能等。而非能动核电厂安全相关涂层工程应用,则需从涂层的模拟DBA性能、干膜密度、导热性能、涂层碎片(数量、大小、位置和性能等)以及包络涂层碎片后的碎片裕量等角度进行综合评估,以确定在事故工况下涂层的可靠性,不对系统安全产生影响,保证核电厂更安全、高效和经济性运行。 展开更多
关键词 安全相关涂层 核电厂 可靠性 设计基准事故 涂层碎片
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木本植物应对干旱胁迫的响应机制:基于水力学性状视角 被引量:2
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作者 程莉 李玉霖 +3 位作者 宁志英 杨红玲 詹瑾 姚博 《生态学报》 CAS CSCD 北大核心 2024年第7期2688-2705,共18页
干旱最显著的影响表现在区域尺度的森林死亡事件中,可以在短时间内杀死数百万棵树木。鉴于未来极端干旱事件的频率和强度可能随温度的升高而增加,迫切需要明确树木对干旱胁迫的响应对策以及衰退死亡机理,揭示木本植物在干旱环境中存活... 干旱最显著的影响表现在区域尺度的森林死亡事件中,可以在短时间内杀死数百万棵树木。鉴于未来极端干旱事件的频率和强度可能随温度的升高而增加,迫切需要明确树木对干旱胁迫的响应对策以及衰退死亡机理,揭示木本植物在干旱环境中存活和死亡的生理机制,了解树木在未来气候下的适应机制,提高预测树木对干旱反应的准确性。在常用植物功能性状的基础上,重点纳入与植物水分运输能力及耐旱性相关的水力学性状,系统总结了:1)植物木质部水分运输的物理机制;2)植物应对干旱胁迫的水力响应过程:3)干旱胁迫下木本植物水分利用对策;以及4)干旱胁迫下木本植物衰退/死亡机理。最后,提出3个尚待解决的主要问题:1)加强纳入水力性状阐明植物对干旱胁迫的响应和调节机制;2)加强从全株植物的角度考虑植物不同组织性状间的关系;3)深入探究树木干旱致死机理。 展开更多
关键词 木本植物 干旱胁迫 水力性状 水分运输策略 干旱致死机理
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Generalizing plant–water relations to landscapes 被引量:4
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作者 R.H.Waring J.J.Landsberg 《Journal of Plant Ecology》 SCIE 2011年第1期101-113,共13页
Aims Changing climate and land use patterns make it increasingly important that the hydrology of catchments and ecosystems can be reliably characterized.The aim of this paper is to identify the biophysical factors tha... Aims Changing climate and land use patterns make it increasingly important that the hydrology of catchments and ecosystems can be reliably characterized.The aim of this paper is to identify the biophysical factors that determine the rates of water vapor loss from different types of vegetation,and to seek,from an array of currently available satelliteborne sensors,those that might be used to initialize and drive landscape-level hydrologic models.Important Findings Spatial variation in the mean heights,crowd widths,and leaf area indices(LAI)of plant communities are important structural variables that affect the hydrology of landscapes.Canopy stomatal conductance(G)imposes physiological limitation on transpiration by vegetation.The maximum value of G(Gmax)is closely linked to canopy photosynthetic capacity,which can be estimated via remote sensing of foliar chlorophyll or nitrogen contents.Gcan be modeled as a nonlinear multipliable function of:(i)leaf–air vapor pressure deficit,(ii)water potential gradient between soil and leaves,(iii)photosynthetically active radiation absorbed by the canopy,(iv)plant nutrition,(v)temperature and(vi)the CO_(2) concentration of the air.Periodic surveys with Light Detection and Ranging(LiDAR)and interferometric RADAR,along with high-resolution spectral coverage in the visible,near-infrared,and thermal infrared bands,provide,along with meteorological data gathered from weather satellites,the kind of information required to model seasonal and interannual variation in transpiration and evaporation from landscapes with diverse and dynamic vegetation. 展开更多
关键词 canopy stomatal conductance plant water relations process-based models remote sensing
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Diversity of arbuscular mycorrhizal fungal spore communities and its relations to plants under increased temperature and precipitation in a natural grassland 被引量:7
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作者 SUN XiuFeng SU YuanYing +6 位作者 ZHANG Ying WU MingYu ZHANG Zhe PEI KeQuan SUN LiFu WAN ShiQiang LIANG Yu 《Chinese Science Bulletin》 SCIE EI CAS 2013年第33期4109-4119,共11页
Arbuscular mycorrhizal fungi(AMF)form mutualisms with most plant species,and therefore,understanding how AMF communities will respond to climate change is essential for predictions of changes in plant communities.To e... Arbuscular mycorrhizal fungi(AMF)form mutualisms with most plant species,and therefore,understanding how AMF communities will respond to climate change is essential for predictions of changes in plant communities.To evaluate the impact of global climate change on AMFs and plant-AMF interactions in a natural grassland in Inner Mongolia,both artificial warming and watering treatments were assigned to experimental plots.Our results indicate that(1)warming and precipitation significantly affected the relative spore abundance of abundant sporulating AMF species;(2)the relative abundance of weak sporulating AMF species and AMF diversity decreased under experimental warming;(3)evidence was found that the composition of the AMF community in a given year might be correlated with plant community composition in the following year;and(4)grasses and forbs showing different preferences to Claroideoglomus etunicatum or Ambispora gerdemannii dominated plots.Our results imply that climate change appears to induce changes in AMF assemblages with knock-on effects on grassland plant communities.AMF communities may play a much more important role than we have thought in the responses of ecosystem to global climate changes. 展开更多
关键词 丛枝菌根真菌 真菌孢子 植物种类 天然草场 多样性 降水 社区 全球气候变化
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