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西部黄土台塬地区生物滞留设施植物群落适配多样性设计研究
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作者 王晶懋 徐浩博 +3 位作者 李兆楠 魏璇 夏颖 毋斯侬 《园林》 2025年第11期35-43,共9页
针对西部黄土台塬地区城市化进程中生态效能不足的问题,结合低影响开发理念,提出生物滞留设施植物群落的适配多样性设计方法,以提升区域生物多样性与雨洪调控协同效益。以渭南城区为研究区域,划分生物滞留设施类型并识别不同类型特征差... 针对西部黄土台塬地区城市化进程中生态效能不足的问题,结合低影响开发理念,提出生物滞留设施植物群落的适配多样性设计方法,以提升区域生物多样性与雨洪调控协同效益。以渭南城区为研究区域,划分生物滞留设施类型并识别不同类型特征差别;针对渭南市典型生态公园及低影响开发项目展开调研,根据场地内部生物滞留设施特征与功能导向的差异筛选典型样方,量化生物滞留设施生物多样性价值,如Margalef丰富度指数最高达3.694,Simpson多样性指数最高达0.9049,匹配优化方法进行生物滞留设施植物群落优化设计。提出适用于西部黄土台塬地区的“生境异质性—生物多样性”双维的生物滞留设施植物群落适配性设计流程;将生物滞留设施划分13种细化类型,提出对应类型的适配多样性设计模式。通过生物多样性、生境条件、生物滞留设施类型的协同考虑,提出适用于黄土台塬地区的生物滞留设施适配多样性优化技术体系,为西北干旱半干旱城市低影响开发的生态效能提升提供科学范式与实践路径。 展开更多
关键词 生物滞留设施 生物多样性 生境条件 植物群落 低影响开发
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环境业绩考核能促进中央企业绿色创新吗?——基于政策准自然实验的证据 被引量:1
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作者 张金康 郭宸昊 权小锋 《管理工程学报》 北大核心 2025年第4期1-16,共16页
中央企业是政府实现节能减排目标的重要力量,如何督促中央企业落实节能减排目标是个值得研究的重要话题。本文基于2010年《中央企业节能减排监督管理暂行办法》的政策作为准自然实验,采用双重差分模型(DID)实证考察了环境业绩考核对中... 中央企业是政府实现节能减排目标的重要力量,如何督促中央企业落实节能减排目标是个值得研究的重要话题。本文基于2010年《中央企业节能减排监督管理暂行办法》的政策作为准自然实验,采用双重差分模型(DID)实证考察了环境业绩考核对中央企业绿色创新的影响。研究结果表明:(1)环境业绩考核显著提升了中央企业绿色创新水平;(2)企业负责人晋升预期越高和薪酬激励越强,环境业绩考核对中央企业绿色创新水平的提升作用越明显;(3)进一步发现,环境业绩考核提升了中央企业绿色创新质量,并且促使中央企业更多地进行联合绿色创新;环境业绩考核对中央企业绿色创新的影响主要存在于非高科技企业、国资委重点关注类行业和市场化程度高的地区;(4)价值分析发现,环境业绩考核通过绿色创新提升了中央企业价值。本文扩展和深化了中央企业业绩考核和绿色创新的相关研究,并对我国政府制定环保政策提供了政策启示。 展开更多
关键词 绿色创新 环境业绩考核 企业价值 中央企业
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Enhancing carbon sequestration and greenhouse gas mitigation in semiarid farmland:The promising role of biochar application with biodegradable film mulching 被引量:2
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作者 Jinwen Pang Zhonghong Tian +9 位作者 Mengjie Zhang Yuhao Wang Tianxiang Qi Qilin Zhang Enke Liu Weijun Zhang Xiaolong Ren Zhikuan Jia Kadambot H.M.Siddique Peng Zhang 《Journal of Integrative Agriculture》 2025年第2期517-535,共19页
Long-term mulching has improved crop yields and farmland productivity in semiarid areas,but it has also increased greenhouse gas(GHG)emissions and depleted soil fertility.Biochar application has emerged as a promising... Long-term mulching has improved crop yields and farmland productivity in semiarid areas,but it has also increased greenhouse gas(GHG)emissions and depleted soil fertility.Biochar application has emerged as a promising solution for addressing these issues.In this study,we investigated the effects of four biochar application rates(no biochar(N)=0 t ha^(-1),low(L)=3 t ha^(-1),medium(M)=6 t ha^(-1),and high(H)=9 t ha^(-1))under film mulching and no mulching conditions over three growing seasons.We assessed the impacts on GHG emissions,soil organic carbon sequestration(SOCS),and maize yield to evaluate the productivity and sustainability of farmland ecosystems.Our results demonstrated that mulching increased maize yield(18.68-41.80%),total fixed C in straw(23.64%),grain(28.87%),and root(46.31%)biomass,and GHG emissions(CO_(2),10.78%;N_(2)O,3.41%),while reducing SOCS(6.57%)and GHG intensity(GHGI;13.61%).Under mulching,biochar application significantly increased maize yield(10.20%),total fixed C in straw(17.97%),grain(17.69%)and root(16.75%)biomass,and SOCS(4.78%).Moreover,it reduced the GHG emissions(CO_(2),3.09%;N_(2)O,6.36%)and GHGI(12.28%).These effects correlated with the biochar addition rate,with the optimal rate being 9.0 t ha^(-1).In conclusion,biochar application reduces CO_(2) and N_(2)O emissions,enhances CH_(4) absorption,and improves maize yield under film mulching.It also improves the soil carbon fixation capacity while mitigating the warming potential,making it a promising sustainable management method for mulched farmland in semiarid areas. 展开更多
关键词 BIOCHAR film mulching greenhouse gas emissions carbon sequestration
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Combining slow-release fertilizer and plastic film mulching reduced the carbon footprint and enhanced maize yield on the Loess Plateau 被引量:2
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作者 Xiaoqing Han Pengfei Dang +12 位作者 Lechen Liao Fangqi Song Miaomiao Zhang Maoxue Zhang Guoqing Li Shuyue Wen Ning Yang Xiping Pan Xiaofan Wang WenWang Xiaoliang Qin Charles O.Joseph Kadambot H.M.Siddique 《Journal of Environmental Sciences》 2025年第1期359-369,共11页
Agricultural practices significantly contribute to greenhouse gas(GHG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production.Plastic film mulc... Agricultural practices significantly contribute to greenhouse gas(GHG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production.Plastic film mulching is commonly used in the Loess Plateau region.Incorporating slow-release fertilizers as a replacement for urea within this practice can reduce nitrogen losses and enhance crop productivity.Combining these techniques represents a novel agricultural approach in semi-arid areas.However,the impact of this integration on soil carbon storage(SOCS),carbon footprint(CF),and economic benefits has received limited research attention.Therefore,we conducted an eight-year study(2015-2022)in the semi-arid northwestern region to quantify the effects of four treatments[urea supplied without plastic film mulching(CK-U),slow-release fertilizer supplied without plastic film mulching(CK-S),urea supplied with plastic film mulching(PM-U),and slow-release fertilizer supplied with plastic film mulching(PM-S)]on soil fertility,economic and environmental benefits.The results revealed that nitrogen fertilizer was the primary contributor to total GHG emissions(≥71.97%).Compared to other treatments,PM-S increased average grain yield by 12.01%-37.89%,water use efficiency by 9.19%-23.33%,nitrogen accumulation by 27.07%-66.19%,and net return by 6.21%-29.57%.Furthermore,PM-S decreased CF by 12.87%-44.31%and CF per net return by 14.25%-41.16%.After eight years,PM-S increased SOCS(0-40 cm)by 2.46%,while PM-U decreased it by 7.09%.These findings highlight the positive effects of PM-S on surface soil fertility,economic gains,and environmental benefits in spring maize production on the Loess Plateau,underscoring its potential for widespread adoption and application. 展开更多
关键词 Plastic film mulching Slow-release fertilizer Maize grain yield Carbon footprint Economic benefits
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Critical review of biochar for the removal of emerging inorganic pollutants from wastewater 被引量:1
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作者 Chong Liu Nanthi Bolan +5 位作者 Anushka Upamali Rajapaksha Hailong Wang Paramasivan Balasubramanian Pengyan Zhang Xuan Cuong Nguyen Fayong Li 《Chinese Chemical Letters》 2025年第2期99-107,共9页
Current research primarily focuses on emerging organic pollutants,with limited attention to emerging inorganic pollutants (EIPs).However,due to advances in detection technology and the escalating environmental and hea... Current research primarily focuses on emerging organic pollutants,with limited attention to emerging inorganic pollutants (EIPs).However,due to advances in detection technology and the escalating environmental and health challenges posed by pollution,there is a growing interest in treating waters contaminated with EIPs.This paper explores biochar characteristics and modification methods,encompassing physical,chemical,and biological approaches for adsorbing EIPs.It offers a comprehensive review of research advancements in employing biochar for EIPs remediation in water,outlines the adsorption mechanisms of EIPs by biochar,and presents an environmental and economic analysis.It can be concluded that using biochar for the adsorption of EIPs in wastewater exhibits promising potential.Nonetheless,it is noteworthy that certain EIPs like Au(III),Rh(III),Ir(III),Ru(III),Os(III),Sc(III),and Y(III),have not been extensively investigated regarding their adsorption onto biochar.This comprehensive review will catalyze further inquiry into the biochar-based adsorption of EIPs,addressing current research deficiencies and advancing the practical implementation of biochar as a potent substrate for EIP removal from wastewater streams. 展开更多
关键词 BIOCHAR Emerging inorganic pollutants Adsorption Metal ions Emerging pollutants REMOVAL Emerging contaminants
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Temperament and production in ruminants:The microbiome as one of the factors that affect temperament
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作者 Feifan Wu Luoyang Ding +2 位作者 Shane K Maloney Dominique Blache Mengzhi Wang 《Journal of Integrative Agriculture》 2025年第11期4111-4126,共16页
The temperament of ruminants has been investigated for several decades and has similarities with human temperament.Temperament represents an animal's response to situations perceived as challenging.This behavioral... The temperament of ruminants has been investigated for several decades and has similarities with human temperament.Temperament represents an animal's response to situations perceived as challenging.This behavioral trait can influence numerous biological functions,primarily the stress axis,affecting production characteristics and animal welfare.A crucial aspect of temperament expression lies in how individuals perceive stressors.Molecular research has begun to elucidate the central pathways involved in the expression of temperament.Recent investigations suggest that the rumen microbiome may influence temperament,like the way that the effect of the gut microbiota on the brain in monogastric species.Further research is necessary to understand the relationship between the gut microbiome and ruminant temperament.Future applications may include modifying the temperament of production animals through the manipulation of the rumen microbiota and potentially enhancing their health and welfare. 展开更多
关键词 TEMPERAMENT SNP RUMINANTS GENOTYPE PHENOTYPE MEAT milk
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Increased hormone activity promotes silk development and heat tolerance during the floret differentiation stage in maize
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作者 Huiqin Wang Jing Sun +8 位作者 Hao Ren Bin Zhao Yuting Li Zishan Zhang Baizhao Ren Aziz Khan Jiwang Zhang Yinglong Chen Peng Liu 《The Crop Journal》 2025年第2期545-555,共11页
Heat stress,a major challenge in modern agriculture due to global warming,significantly reduces crop productivity.To mitigate its adverse effects on maize yield,it is crucial to understand the mechanisms by which heat... Heat stress,a major challenge in modern agriculture due to global warming,significantly reduces crop productivity.To mitigate its adverse effects on maize yield,it is crucial to understand the mechanisms by which heat stress impacts reproductive development.This study investigated the impact of heat stress during the 12th leaf(V12)stage,where silk development begins on grain yield formation,using heat-sensitive and heat-tolerant cultivars.Compared to pollen,silks were found to be more vulnerable to heat stress.Heat stress disrupted hormone balance and inhibited hormone signaling transduction pathways in silks,delaying silk emergence from bracts and reducing fertilization and grain yield.The heat-tolerant cultivar maintained silk growth by activating more response pathways,displaying faster hormone responses,and up-regulating hormones.Taken together,we propose that hormones play an essential role in silk development and later fertilization process. 展开更多
关键词 Zea mays L Heat stress TRANSCRIPTOMICS HORMONES SILK
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青蒿琥酯缓解大鼠模型椎间盘退变的研究
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作者 谭晶 雷桂华 +1 位作者 郭书君 吕凤娟 《热带医学杂志》 2025年第8期1007-1011,F0002,1028,共7页
目的探究青蒿琥酯(Art)对大鼠椎间盘内炎症反应和退变进程的影响。方法选取8周龄雌性SD大鼠25只,使用细针在大鼠尾椎间盘注射炎症因子白细胞介素-1β(IL-1β)诱导椎间盘退变,并注射青蒿琥酯药物,随机分为对照组(CTRL组)、模型组(IL-1β... 目的探究青蒿琥酯(Art)对大鼠椎间盘内炎症反应和退变进程的影响。方法选取8周龄雌性SD大鼠25只,使用细针在大鼠尾椎间盘注射炎症因子白细胞介素-1β(IL-1β)诱导椎间盘退变,并注射青蒿琥酯药物,随机分为对照组(CTRL组)、模型组(IL-1β组)和青蒿琥酯干预组(IL-1β+Art组)。术后1~2周取大鼠尾椎间盘,应用X线片拍摄评估椎间盘高度指数,应用苏木精-伊红(HE)和马松染色显示大鼠尾椎间盘组织病理变化,实时荧光定量聚合酶链式反应(qPCR)检测退变相关基因蛋白聚糖(ACAN)、Ⅱ型胶原(COL2A1)和Y染色体性别决定区-盒转录因子9(SOX9)的mRNA表达水平,免疫组织化学染色检测炎症因子环氧合酶-2(COX2)、IL-1β和白细胞介素-6(IL-6)的表达,天狼星红染色观察组织纤维化程度。结果X线片结果显示,与CTRL组相比,IL-1β组椎间隙高度在术后1周和2周显著下降,差异均有统计学意义(t=2.485、6.078,P=0.048、0.001)。HE染色和Masson染色结果显示,IL-1β组在术后2周时髓核区域变小,纤维环与髓核边界不清;qPCR结果显示,IL-1β组的ACAN、COL2A1和SOX9的mRNA表达水平显著下调,与CTRL组相比差异均有统计学意义(t=17.497、23.023、26.744,P均<0.05),表明椎间盘退变模型成功建立。与IL-1β组相比,IL-1β+Art组在术后1、2周能延缓椎间盘退变导致的椎间隙高度降低,差异均有统计学意义(t=4.105、3.473,P=0.006、0.018);能改善椎间盘退变过程中的纤维环断裂、排列紊乱和髓核丢失,恢复椎间盘的组织结构,减轻椎间盘退变过程中胞外基质COL2A1、ACAN和SOX9的降解,上调COL2A1、ACAN和SOX9 mRNA表达水平,差异均有统计学意义(t=4.999、6.760、4.689,P均<0.05)。与CTRL组相比,免疫组织化学染色表明IL-1β组内炎症因子COX2、IL-1β和IL-6表达水平在术后1、2周显著上调(t_(1周)=21.392、7.765、19.271,t_(2周)=19.565、3.298、18.603,P均<0.05)。天狼星红染色结果显示,IL-1β组的纤维环紊乱,Ⅲ/Ⅰ型胶原比例失调。与IL-1β组相比,IL-1β+Art组椎间盘内炎症因子COX2、IL-1β和IL-6表达水平在术后1、2周下降,差异均有统计学意义(t_(1周)=24.643、4.741、11.729,t_(2周)=6.935、3.324、13.310,P均<0.05),逆转Ⅲ/Ⅰ型胶原比例,延缓组织纤维化进程。结论青蒿琥酯具有抗椎间盘炎症和纤维化的作用,并缓解椎间盘退变,具有作为治疗椎间盘退变的药物潜力。 展开更多
关键词 青蒿琥酯 椎间盘退变 炎症 纤维化
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Phenotypic advantages and improved genomic stability following selection in advanced selfing-generations of Brassica allohexaploids
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作者 Yan Niu Rui Yang +9 位作者 Zelong Li Zhengxuan Huo Shihao Chang Entang Tian Han Qin Wallace A.Cowling Kadambot H.M.Siddique Annaliese S.Mason Sheng Chen Jun Zou 《Journal of Genetics and Genomics》 2025年第6期799-811,共13页
Allopolyploids often exhibit advantages in vigor and adaptability compared to diploids.A long-term goal in the economically important Brassica genus has been to develop a new allohexaploid crop type(AABBCC)by combinin... Allopolyploids often exhibit advantages in vigor and adaptability compared to diploids.A long-term goal in the economically important Brassica genus has been to develop a new allohexaploid crop type(AABBCC)by combining different diploid and allotetraploid crop species.However,early-generation allohexaploids often face challenges like unstable meiosis and low fertility,and the phenotypic performance of these synthetic lines has rarely been assessed.This study analyzes agronomic traits,fertility,and genome stability in ArArBcBcCcCc lines derived from four crosses between B.carinata and B.rapa after 9–11 selfing generations.Our results demonstrate polyploid advantage in vigor and seed traits,considerable phenotypic variation,and high fertility and genome stability.Meanwhile,parental genotypes significantly influence outcomes in advanced allohexaploids.Structural variants,largely resulting from A–C homoeologous exchanges,contribute to genomic variation and influence hexaploid genome stability,with the A sub-genome showing the highest variability.Both positive and negative impacts of SVs on fertility and seed weight are observed.Pseudo-euploids,frequently appearing,do not significantly affect fertility or other agronomic traits compared to euploids,indicating a potential pathway toward a stable allohexaploid species.These findings provide insights into the challenge and potential for developing an adaptable and stable Brassica hexaploid through selection. 展开更多
关键词 Brassica species Synthetic allohexaploid Homoeologous exchange Genome stability Polyploid advantage Structural variants
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Monitoring abandoned cropland in the hilly and gully regions of the Loess Plateau using Landsat time series images
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作者 Chenxiao Duan Jiabei Li +3 位作者 Shufang Wu Liming Yu Hao Feng Kadambot H M Siddique 《Journal of Integrative Agriculture》 2025年第11期4430-4450,共21页
Cropland abandonment has become a global issue that poses significant threats to sustainable cropland management,national food security,and the ecological environment.Remote sensing technology is crucial for identifyi... Cropland abandonment has become a global issue that poses significant threats to sustainable cropland management,national food security,and the ecological environment.Remote sensing technology is crucial for identifying and monitoring abandoned cropland in large-scale areas.However,limited information is available on the effective identification methods and spatial distribution patterns of abandoned cropland in the hilly and gully regions.This study introduced two methods-the land-use trajectory and normalized difference vegetation index(NDVI)time series-for monitoring abandoned cropland and evaluating its spatial distribution in Yanhe River Basin using Landsat-8 images from 2019 to 2021.The results showed that using a random forest algorithm,high-precision annual land-use classifications were achieved with the generation of reliable land-cover samples and an optimized feature dataset.The overall accuracy(OA)and Kappa coefficient of the land-use maps exceeded 90% and 0.88,respectively,demonstrating the effectiveness of the classification over three years.These two distinct change detection methods were used to identify abandoned cropland in the study area,and their accuracy and effectiveness were evaluated.The land-use trajectory method performed better than the NDVI time series method for extracting abandoned cropland,with an OA of 83.5% and an F1 score of 84.7%.According to the land-use trajectory detection results,the study area had 164.6 km^(2) of abandoned cropland area in 2021,with an abandonment rate of 16.3%.Furthermore,cropland abandonment mainly occurred in the northwestern part of the region,which has harsh natural conditions,while abandonment was rare in the southern and eastern regions.Topography and landforms significantly influenced the spatial distribution of abandoned cropland,with most abandoned cropland located in mountainous regions with higher elevations and steeper slopes.The abandonment rate generally increased with the elevation and slope.These findings provide valuable references and guidance for selecting appropriate methods to identify abandoned cropland and analyze its spatial distribution in the hilly and gully regions.Our proposed methods offer robust solutions for monitoring abandoned cropland and optimizing land-use change detection in similar regions with complex landforms. 展开更多
关键词 cropland abandonment Landsat time series land-use mapping change detection spatial distribution hilly and gully regions
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Harnessing metabolomics for enhanced crop drought tolerance 被引量:1
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作者 Ali Raza Muhammad Anas +10 位作者 Savita Bhardwaj Rakeeb Ahmad Mir Sidra Charagh Minhas Elahi Xinyue Zhang Reyazul Rouf Mir Wolfram Weckwerth Alisdair R.Fernie Kadambot H.M.Siddique Zhangli Hu Rajeev K.Varshney 《The Crop Journal》 2025年第2期311-327,共17页
Global crop productivity faces a significant threat from climate change-induced drought stress(DS),which is vital for sustainable agriculture and global food security.Uncovering DS adaptation and tolerance mechanisms ... Global crop productivity faces a significant threat from climate change-induced drought stress(DS),which is vital for sustainable agriculture and global food security.Uncovering DS adaptation and tolerance mechanisms in crops is necessary to alleviate climate challenges.Innovative plant breeding demands revolutionary approaches to develop stress-smart plants.Metabolomics,a promising field in plant breeding,offers a predictive tool to identify metabolic markers associated with plant performance under DS,enabling accelerated crop improvement.Central to DS adaptation is metabolomics-driven metabolic regulation,which is critical for maintaining cell osmotic potential in crops.Recent innovations allow rapid mapping of specific metabolites to their genetic pathways,providing a valuable resource for plant scientists.Metabolomics-driven molecular breeding,integrating techniques such as mQTL and mGWAS,enhances our ability to discover key genetic elements linked to stress-responsive metabolites.This integration offers a beneficial platform for plant scientists,yielding significant insights into the complex metabolic networks underlying DS tolerance.Therefore,this review discusses(1)insights into metabolic regulation for DS adaptation,(2)the multifaceted role of metabolites in DS tolerance and nutritional/yield trait improvement,(3)the potential of single-cell metabolomics and imaging,(4)metabolomics-driven molecular breeding,and(5)the application of metabolic and genetic engineering for DS-tolerant crops.We finally propose that the metabolomics-driven approach positions drought-smart crops as key contributors to future food production,supporting the vital goal of achieving“zero hunger”. 展开更多
关键词 Amino acids Climate change Food security mQTL and mGWAS Metabolic engineering Single-cell metabolomics Water scarcity
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丛枝菌根结构与功能研究进展 被引量:47
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作者 田蜜 陈应龙 +1 位作者 李敏 刘润进 《应用生态学报》 CAS CSCD 北大核心 2013年第8期2369-2376,共8页
丛枝菌根(arbuscular mycorrhiza,AM)是陆地生态系统中分布最广泛、最重要的互惠共生体之一,对提高植物抗逆性、修复污染生境、保持生态系统稳定与可持续生产力的作用显著.AM结构特征是判断菌根形成的主要指标,与其功能密切相关.本文总... 丛枝菌根(arbuscular mycorrhiza,AM)是陆地生态系统中分布最广泛、最重要的互惠共生体之一,对提高植物抗逆性、修复污染生境、保持生态系统稳定与可持续生产力的作用显著.AM结构特征是判断菌根形成的主要指标,与其功能密切相关.本文总结了AM丛枝结构、泡囊结构、菌丝结构和侵入点结构等发育特征;分析了A型丛枝结构、P型丛枝结构、泡囊结构和根外菌丝结构与促进寄主植物养分吸收和生长、提高植物抗旱性、耐涝性、耐盐性、抗高温、拮抗病原物、提高植物抗病性、抗重金属毒性、分解有毒有机物、修复污染与退化土壤等功能的关系,及其所发挥的重要作用;探讨了影响AM结构与功能的因子,以及基于AM不同结构所发挥功能的作用机制.旨在为系统研究AM真菌发育特征、AM真菌效能机制,以及评价和筛选AM真菌高效菌种提供依据. 展开更多
关键词 丛枝菌根 丛枝菌根真菌 侵染 寄主植物
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菌根真菌多样性与植物多样性的相互作用研究进展 被引量:25
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作者 王浩 吴爱姣 +2 位作者 刘保兴 刘润进 陈应龙 《微生物学通报》 CAS CSCD 北大核心 2020年第11期3918-3932,共15页
菌根共生双方多样性影响着生态系统的过程与功能。菌根真菌-寄主植物之间的共生组合存在偏好性或特异性,这导致菌根真菌对寄主植物的效益差异和寄主植物对菌根真菌的利益差别:两者在互利共生过程中不仅相互选择,还存在相互促进与制约的... 菌根共生双方多样性影响着生态系统的过程与功能。菌根真菌-寄主植物之间的共生组合存在偏好性或特异性,这导致菌根真菌对寄主植物的效益差异和寄主植物对菌根真菌的利益差别:两者在互利共生过程中不仅相互选择,还存在相互促进与制约的关系(如互补与选择效应、竞争),从而在一定程度上决定生态系统的演化与发展。本文概述了植物多样性与菌根真菌多样性的相互影响,探讨了两者互作可能存在的调控因素与机制,对存在的问题和争议进行了总结,并提出了进一步研究的方向。深入阐明植物多样性与菌根真菌多样性之间的互作关系,将丰富生物共生学理论,增强菌根应用潜力及生物多样性的维持。 展开更多
关键词 菌根真菌 共生 多样性 生产力 偏好性
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关于Boussinesq型水波方程理论和应用研究的综述 被引量:11
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作者 孙家文 房克照 +3 位作者 刘忠波 范浩煦 孙昭晨 王平 《海洋学报》 CAS CSCD 北大核心 2020年第5期1-11,共11页
Boussinesq型方程是研究水波传播与演化问题的重要工具之一,本文就1967-2018年常用的Boussinesq型水波方程从理论推导和数值应用两个方面进行了回顾,以期推动该类方程在海岸(海洋)工程波浪水动力方向的深入研究和应用。此类方程推导主... Boussinesq型方程是研究水波传播与演化问题的重要工具之一,本文就1967-2018年常用的Boussinesq型水波方程从理论推导和数值应用两个方面进行了回顾,以期推动该类方程在海岸(海洋)工程波浪水动力方向的深入研究和应用。此类方程推导主要从欧拉方程或Laplace方程出发。在一定的非线性和缓坡假设等条件下,国内外学者建立了多个Boussinesq型水波方程,并以Stokes波的相关理论为依据,考察了这些方程在相速度、群速度、线性变浅梯度、二阶非线性、三阶非线性、波幅离散、速度沿水深分布以及和(差)频等多方面性能的精度。将Boussinesq型水波方程分为水平二维和三维两大类,并对主要Boussinesq型水波方程的特性进行了评述。进而又对适合渗透地形和存在流体分层情况下的Boussinesq型水波方程进行了简述与评论。最后对这些方程的应用进行了总结与分析。 展开更多
关键词 BOUSSINESQ型方程 色散性 非线性 变浅性 应用研究
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甲烷在褐煤煤焦上的裂解反应研究 被引量:11
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作者 徐泽夕 吴晋沪 +1 位作者 王洋 张东柯 《燃料化学学报》 EI CAS CSCD 北大核心 2009年第3期277-281,共5页
采用石英管固定床反应器,分别考察了不同温度(1123K、1173K、1223K、1273K)及不同浓度(10%、15%、20%)下,甲烷在褐煤煤焦上的裂解反应。结果表明,褐煤煤焦对甲烷裂解反应具有良好的催化活性,在所考察温度范围内,甲烷的初始转化率最高达9... 采用石英管固定床反应器,分别考察了不同温度(1123K、1173K、1223K、1273K)及不同浓度(10%、15%、20%)下,甲烷在褐煤煤焦上的裂解反应。结果表明,褐煤煤焦对甲烷裂解反应具有良好的催化活性,在所考察温度范围内,甲烷的初始转化率最高达99.5%,温度越高,甲烷的初始转化率越高;但随着反应的进行,转化率逐渐降低;甲烷进气浓度越高,初始转化率越低,而且催化剂失活也越快。反应前后煤焦电镜扫描照片及物性参数的比较表明,甲烷裂解生成炭沉积在煤焦表面,导致煤焦比表面积随反应的进行逐渐降低,与甲烷裂解转化率的变化趋势一致;反应后煤焦的孔容及微孔容都有所降低,平均孔径增大,说明甲烷的裂解生成炭造成了煤焦孔道尤其是微孔的堵塞,比表面积减小,导致了甲烷的转化率降低。 展开更多
关键词 褐煤煤焦 甲烷裂解 合成气 BET SEM
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3种丛枝菌根真菌与3种寄主植物的共生关系 被引量:10
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作者 祝英 刘英霞 +5 位作者 巩晓芳 陈应龙 任爱天 刘润进 金樑 熊友才 《微生物学通报》 CAS CSCD 北大核心 2016年第3期527-533,共7页
【目的】利用丛枝菌根(Arbuscular mycorrhiza,AM)真菌对寄主植物的偏好性和不同寄主植物的功能互补作用,建立AM真菌的高效繁殖体系。【方法】以玉米(Zea may L.)、高粱[Sorghum bicolor(L.)Moench]和白车轴草(Trifolium repens L.)为... 【目的】利用丛枝菌根(Arbuscular mycorrhiza,AM)真菌对寄主植物的偏好性和不同寄主植物的功能互补作用,建立AM真菌的高效繁殖体系。【方法】以玉米(Zea may L.)、高粱[Sorghum bicolor(L.)Moench]和白车轴草(Trifolium repens L.)为寄主植物,采用寄主植物单作和间作的盆栽培养法,研究不同栽培模式对光壁无梗囊霉(Acaulospora laevis)、单孢球囊霉(Glomus monosporum)和根内球囊霉(G.intraradices)3种AM真菌繁殖能力的影响,通过地上部分生物量的分配分析,探索C3和C4植物对AM真菌共生关系的"功能互补"效应及机制。【结果】间作模式下,寄主植物地上部分总生物量和3种AM真菌的孢子密度均显著高于单作(P<0.05);单作和间作栽培模式下,3种AM真菌对玉米地上部分生物量响应无显著差异(P>0.05),但单孢球囊霉和根内球囊霉对高粱地上部分生物量产生显著影响(P<0.05);两种间作栽培模式下,根内球囊霉对白车轴草地上部分生物量也产生了显著影响(P<0.05)。【结论】3种AM真菌对3种寄主植物的共生偏好性不同,且C3和C4植物对AM真菌共生关系存在一定的"功能互补"效应,利用AM真菌的寄主植物偏好性和不同植物间的功能互补关系,增加AM真菌的孢子产量,有利于AM真菌高效繁殖体系的建立。 展开更多
关键词 寄主植物 AM真菌 间作 单作 共生机制
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城市生态系统中丛枝菌根真菌侵染状况及群落特征(英文) 被引量:4
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作者 史立君 于建新 +2 位作者 陈应龙 郭绍霞 刘润进 《菌物学报》 CAS CSCD 北大核心 2019年第11期2016-2029,共14页
作者采集了北京、青岛、济南、南京、武汉和贵阳6个城市中部分大学校园高羊茅Festuca elata、城内公园大叶黄杨Euonymus japonicus及郊区公园连翘Forsythia suspensa根区土样,测定菌根着生状况和丛枝菌根(arbuscular mycorrhizal,AM)AM... 作者采集了北京、青岛、济南、南京、武汉和贵阳6个城市中部分大学校园高羊茅Festuca elata、城内公园大叶黄杨Euonymus japonicus及郊区公园连翘Forsythia suspensa根区土样,测定菌根着生状况和丛枝菌根(arbuscular mycorrhizal,AM)AM真菌孢子密度,形态鉴定AM真菌种类,测定AM真菌种丰度、多样性指数及群落结构等。除从北京中国人民大学校园草坪和南京下马坊公园的大叶黄杨根系上未见丛枝结构外,其他根系样品均观测到典型的丛枝和泡囊结构,丛枝着生率较低,且多为A-型。各城市大多数样品的菌根总侵染率、丛枝着生率和泡囊数分别低于40%、5%和1/mm。北京中国人民大学草坪根系菌根总侵染率显著低于其他城市校区的。除北京香山的连翘和济南山东大学的高羊茅上的种丰度、Shannon指数、以及北京紫竹院公园大叶黄杨上的孢子密度之外,青岛市的3种植物上AM真菌的孢子密度、种丰度和Shannon指数均高于其他城市的。各校园草坪中相同的AM真菌种类较少,但放射球囊霉Glomus radiatum分布频率100%,为校园草坪中的优势种。城市公园以青岛中山公园的AM真菌的孢子密度和种丰度最高;郊区公园以贵阳黔灵山的孢子密度、种丰度和Shannon指数最高,武汉狮子山的种丰度和Shannon指数最低。土壤氮沉降与泡囊数量呈显著负相关,土壤压实程度与泡囊数量呈显著正相关。大叶黄杨根区土壤中AM真菌种丰度与土壤有机质含量呈显著正相关,Shannon指数与土壤pH呈显著正相关。结论认为,中国不同城市生态系统中AM真菌群落结构差异较大,氮沉降和土壤压实程度对根内泡囊数量具有不同的影响。 展开更多
关键词 丛枝菌根真菌 菌根定殖 群落结构 城市土壤 寄主植物
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煤与甲烷共转化过程中煤焦二氧化碳气化动力学研究 被引量:4
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作者 孙志强 吴晋沪 +1 位作者 王洋 ZHANG Dong-ke 《燃料化学学报》 EI CAS CSCD 北大核心 2009年第4期410-415,共6页
以煤与甲烷共转化为背景,运用热重方法进行了由煤焦、甲烷和二氧化碳组成的共转化反应体系中碳的反应动力学研究。在1173 K^1273 K考察了温度对碳转化的影响。结果表明,该反应体系中碳的表观反应速率比煤焦的纯二氧化碳气化速率慢一倍左... 以煤与甲烷共转化为背景,运用热重方法进行了由煤焦、甲烷和二氧化碳组成的共转化反应体系中碳的反应动力学研究。在1173 K^1273 K考察了温度对碳转化的影响。结果表明,该反应体系中碳的表观反应速率比煤焦的纯二氧化碳气化速率慢一倍左右,且表观上碳不能完全被气化。通过改变甲烷和二氧化碳的比例考察了气相组成变化对共转化反应中碳转化速率的影响,发现甲烷浓度的增加和二氧化碳浓度的减少都会降低碳的转化速率,且随着甲烷浓度的增加,表观上碳最终所能达到的转化率也会降低。通过数据分析发现,该反应适合采用均相反应模型进行描述,关联得到其表观活化能为312.4 kJ/mol,甲烷的反应级数为-0.13,二氧化碳的反应级数为0.3。 展开更多
关键词 共转化 甲烷 二氧化碳 动力学 热重
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甲烷和二氧化碳在煤焦上反应制备合成气实验研究 被引量:6
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作者 孙志强 吴晋沪 ZHANG Dong-ke 《燃料化学学报》 EI CAS CSCD 北大核心 2009年第6期641-647,共7页
以煤与甲烷共转化制备合成气的研究为背景,通过考察固定床反应器上甲烷和二氧化碳分别在石英砂、煤灰和煤焦上的反应过程,证实了煤焦中的碳结构在共转化过程中对甲烷转化具有催化作用。同时考察了反应温度(1073K~1223K)、CH4/CO2比(0.3... 以煤与甲烷共转化制备合成气的研究为背景,通过考察固定床反应器上甲烷和二氧化碳分别在石英砂、煤灰和煤焦上的反应过程,证实了煤焦中的碳结构在共转化过程中对甲烷转化具有催化作用。同时考察了反应温度(1073K~1223K)、CH4/CO2比(0.33~3.00)和气固接触时间等工艺条件对甲烷转化率、气相产物中H2/CO比的影响。结果表明,甲烷的转化率随着反应温度和气固接触时间的增加而增大,随CH4/CO2比的增加而减小。在考察范围内甲烷的转化率最高达到了86%。反应物中CH4/CO2比的改变可以起到调节产品气中H2/CO比的作用,0.4~2.0调节。 展开更多
关键词 甲烷 二氧化碳 煤焦 共转化 H2/CO比
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煤与甲烷共转化制合成气过程的热力学分析 被引量:7
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作者 张元 吴晋沪 张东柯 《燃料化学学报》 EI CAS CSCD 北大核心 2010年第1期12-16,共5页
采用Gibbs自由能最小法,对流化床煤与甲烷共转化过程进行了热力学分析。在保持体系绝热温度为常压流化床煤气化的操作温度1 273 K下,将煤与甲烷共转化过程的冷煤气效率、产出合成气的单位有效能氧耗及H2/CO比等指标与单纯煤气化过程进... 采用Gibbs自由能最小法,对流化床煤与甲烷共转化过程进行了热力学分析。在保持体系绝热温度为常压流化床煤气化的操作温度1 273 K下,将煤与甲烷共转化过程的冷煤气效率、产出合成气的单位有效能氧耗及H2/CO比等指标与单纯煤气化过程进行了比较。结果表明,在煤气化体系中增加甲烷进料,能使冷煤气效率提高,单位有效能氧耗降低,产出合成气的H2/CO比可调。此外,甲烷可作为部分氢源,降低过程水耗。从热力学角度证明了煤与甲烷共转化方法对于有效利用煤层气的优越性,所得出的操作线也为该过程的实际操作指出了方向。 展开更多
关键词 煤气化 甲烷 共转化 热力学分析
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