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体育产业对江西省区域经济发展的影响研究
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作者 谭文辉 黄平 《商场现代化》 北大核心 2007年第10Z期237-238,共2页
本文阐述了体育产业的概念,通过对江西省体育产业结构现状的分析,阐述了体育产业对江西省区域经济的影响,并在此基础上提出体育产业将为江西省经济持续发展发挥更重要的作用。
关键词 体育产业 区域经济 江西省
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城市化对唐山市水环境的影响研究 被引量:3
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作者 张月明 《水资源开发与管理》 2018年第1期50-53,共4页
本文针对唐山市城市建设现状,通过监测、分析城市化对水循环系统、水质变化、河流生态环境的影响,探讨水环境发展规律,选择种植对水质有很强净化作用的植物、改变工程调度方式衰减COD浓度、区域水生动物群落补救及合理配置水资源等措施... 本文针对唐山市城市建设现状,通过监测、分析城市化对水循环系统、水质变化、河流生态环境的影响,探讨水环境发展规律,选择种植对水质有很强净化作用的植物、改变工程调度方式衰减COD浓度、区域水生动物群落补救及合理配置水资源等措施助益水生态改善,最大利好城市发展。 展开更多
关键词 城市化 水循环 水质 水环境 唐山市
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上海社区老年人健康促进生活方式影响因素分析 被引量:2
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作者 王汉哲 许铭星 《应用数学进展》 2020年第11期2046-2052,共7页
目的:研究上海社区老年人健康促进生活方式现状及其影响因素。方法:采用一般情况调查表和中文版老年人健康促进生活方式量表对上海社区老年人基本情况和生活方式现状进行调查。结果:老年人健康促进生活方式量表平均得分为(96.63 &#1... 目的:研究上海社区老年人健康促进生活方式现状及其影响因素。方法:采用一般情况调查表和中文版老年人健康促进生活方式量表对上海社区老年人基本情况和生活方式现状进行调查。结果:老年人健康促进生活方式量表平均得分为(96.63 &#177;16.91)分。各量表得分依次为:饮食营养维度得分为(13.06 &#177;2.00)分,运动锻炼维度得分为(10.22 &#177;2.61)分,精神成长维度得分为(14.17 &#177;3.34)分,健康责任维度得分为(22.08 &#177;5.59)分,压力应对维度得分为(19.24 &#177;3.96)分,人际关系维度得分为(17.86 &#177;3.03)分。年龄、健康关注度、健康自我效能、公共健康设施健全程度和公共健康服务开展情况对老年人健康促进生活方式存在显著影响。结论:上海社区老年人健康促进生活方式水平为中等偏上,可通过提升健康自我效能、增加健康关注度、开展多种公共健康服务,健全公共健康设施来提高老年人健康促进生活方式水平,从而改善其健康状况。 展开更多
关键词 老年人 健康促进 生活方式 影响因素
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缩节胺和硝普钠对棉花幼苗根际土壤酶活性及细菌群落的影响
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作者 吴建飞 刘茜 +3 位作者 李璇 温天旺 杨文亭 汤飞宇 《棉花学报》 CSCD 北大核心 2023年第5期353-364,共12页
【目的】研究棉花幼苗施用缩节胺(1,1-dimethyl piperidinium chloride,DPC)和一氧化氮供体硝普钠(sodium nitroprusside,SNP)后根际土壤酶活性及细菌群落的变化,探讨与棉花幼苗生长相关的根际生物学指标。【方法】采用陆地棉品系A201... 【目的】研究棉花幼苗施用缩节胺(1,1-dimethyl piperidinium chloride,DPC)和一氧化氮供体硝普钠(sodium nitroprusside,SNP)后根际土壤酶活性及细菌群落的变化,探讨与棉花幼苗生长相关的根际生物学指标。【方法】采用陆地棉品系A201进行穴盘育苗试验。于棉花1叶1心期分别在叶片均匀涂抹50 mg·L^(-1)DPC、500μmol·L^(-1)SNP,以涂抹去离子水为对照。于3叶1心期取根际土壤分析蔗糖酶、脲酶、过氧化氢酶、碱性磷酸酶活性,采用16S rRNA测序技术分析根际细菌多样性。【结果】DPC和SNP处理显著促进棉花根系生长,显著提高茎粗和植株干物质质量。DPC处理显著提高土壤脲酶和蔗糖酶的活性,SNP处理显著提高土壤蔗糖酶活性但显著降低脲酶的活性,但是DPC和SNP处理均未显著影响过氧化氢酶和碱性磷酸酶活性。DPC处理显著提高髌骨菌门(Patescibacteria)的相对丰度和土壤细菌群落的辛普森多样性指数(Simpson's diversity index),显著降低了绿弯菌门(Chloroflexi)和酸杆菌门(Acidobacteria)的相对丰度以及土壤细菌群落的香农-维纳多样性指数(Shannon Wiener’s diversity index)。冗余分析显示,DPC处理组的酵母菌科(Saccharimonadaceae)、TM7a属细菌的相对丰度比SNP处理组和对照组高;SNP处理组的纤维弧菌属(Cellvibrionaceae)细菌相对丰度高于DPC处理组和对照组;DPC和SNP处理组的根瘤菌科(Rhizobiaceae)细菌的相对丰度高于对照组,硝化螺旋菌科(Nitrospiraceae)和硝化螺旋菌属(Nitrospira)细菌的相对丰度低于对照组。脲酶活性与酵母菌科、TM7a属细菌的相对丰度呈显著正相关关系。【结论】DPC和SNP能够促进棉花幼苗根系及植株生长,并影响棉苗根际的土壤酶活性及细菌群落结构。 展开更多
关键词 棉花 缩节胺 硝普钠 土壤酶 细菌群落 丰度 多样性
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不同植物生长调节剂对冬小麦生长及产量的影响 被引量:3
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作者 张飞雪 陈峰 +2 位作者 张书红 马延东 刘锐杰 《肥料与健康》 CAS 2023年第6期58-61,66,共5页
为考察不同植物生长调节剂对农作物生长状况及产量的影响,以氨基寡糖素、复硝酚钠和胺鲜酯为处理药剂,以复合肥(18-15-12)为药剂载体,于冬小麦播种前底施于土壤,测定了不同生育时期冬小麦的株高、主根长、须根数、分蘖数、叶片数、顶节... 为考察不同植物生长调节剂对农作物生长状况及产量的影响,以氨基寡糖素、复硝酚钠和胺鲜酯为处理药剂,以复合肥(18-15-12)为药剂载体,于冬小麦播种前底施于土壤,测定了不同生育时期冬小麦的株高、主根长、须根数、分蘖数、叶片数、顶节长、穗长、旗叶长、颖果数等指标。结果表明:氨基寡糖素在冬小麦前期能促苗生根,中期能促叶、增加分蘖数,提高冬小麦产量;复硝酚钠主要表现在中后期能促进冬小麦株高和旗叶的生长;胺鲜酯在冬小麦前期对茎叶、须根数,在中期对顶节长、颖果数具有促进作用,但后期对顶节长、旗叶长和颖果数有抑制作用;复硝酚钠和胺鲜酯均会降低冬小麦产量。 展开更多
关键词 植物生长调节剂 冬小麦 氨基寡糖素 复硝酚钠 胺鲜酯
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Influencing factors analysis of hard limestone reformation and strength weakening under acidic effect
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作者 HOU Ming-xiao HUANG Bing-xiang +2 位作者 ZHAO Xing-long JIAO Xue-jie ZHENG Chen-yang 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2446-2466,共21页
Roof disaster has always been an important factor restricting coal mine safety production.Acidic effect can reform the rock mass structure to weaken the macroscopic strength characteristics,which is an effective way t... Roof disaster has always been an important factor restricting coal mine safety production.Acidic effect can reform the rock mass structure to weaken the macroscopic strength characteristics,which is an effective way to control the hard limestone roof.In this study,the effects of various factors on the reaction characteristics and mechanical properties of limestone were analyzed.The results show that the acid with stronger hydrogen production capacity after ionization(pK_(a)<0)has more prominent damage to the mineral grains of limestone.When pKa increases from−8.00 to 15.70,uniaxial compressive strength and elastic modulus of limestone increase by 117.22%and 75.98%.The influence of acid concentration is manifested in the dissolution behavior of mineral crystals,the crystal defects caused by large-scale acid action will lead to the deterioration of limestone strength,and the strength after 15%concentration reformation can be reduced by 59.42%.The effect of acidification time on limestone has stages and is the most obvious in the initial metathesis reaction stage(within 60 min).The key to the strength damage of acidified limestone is the participation of hydrogen ions in the reaction system.Based on the analytic hierarchy process method,the influence weights of acid type,acid concentration and acidification time on strength are 24.30%,59.54% and 16.16%,respectively.The research results provide theoretical support for the acidification control of hard limestone roofs in coal mines. 展开更多
关键词 hard roof acidic effect structural reformation strength weakening influencing factors
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Temperature effects on the failure of deep circular tunnel under true-triaxial compression
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作者 HUANG Lin-qi LIU Mao-lin +4 位作者 WANG Zhao-wei GUO Yi-de SI Xue-feng LI Xi-bing LI Chao 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3119-3141,共23页
The failure characteristics of thermal treated surrounding rocks should be studied to evaluate the stability and safety of deep ground engineering under high-ground-temperature and high-ground-stress conditions.The fa... The failure characteristics of thermal treated surrounding rocks should be studied to evaluate the stability and safety of deep ground engineering under high-ground-temperature and high-ground-stress conditions.The failure process of the inner walls of fine-grained granite specimens at different temperatures(25–600℃)was analyzed using a true-triaxial test system.The failure process,peak intensity,overall morphology(characteristics after failure),rock fragment characteristics,and acoustic emission(AE)characteristics were analyzed.The results showed that for the aforementioned type of granite specimens,the trend of the failure stress conditions changed with respect to the critical temperature(200℃).When the temperature was less than 200℃,the initial failure stress increased,final failure stress increased,and failure severity decreased.When the temperature exceeded 200℃,the initial failure stress decreased,final failure stress decreased,and failure severity increased.When the temperature was 600℃,the initial and final failure stresses of the specimens decreased by 60.93%and 19.77%compared with those at 200℃,respectively.The numerical results obtained with the software RFPA3D-Thermal were used to analyze the effect of temperature on the specimen and reveal the mechanism of the failure process in the deep tunnel surrounding rock. 展开更多
关键词 deep ground rock failure GRANITE thermal treatment true-triaxial test circular tunnel RFPA3D-Thermal
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Characteristics and fate behavior of environmentally persistent free radicals in atmospheric particulate matter
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作者 WANG Xueying CUI Long +2 位作者 XUE Yonggang HO Kinfai HUANG Yu 《地球环境学报》 CSCD 2024年第4期596-611,共16页
Background,aim,and scope Environmentally persistent free radicals(EPFRs)have received significant attention due to their longer lifetime and stable existence in various environments.The strong environmental migration ... Background,aim,and scope Environmentally persistent free radicals(EPFRs)have received significant attention due to their longer lifetime and stable existence in various environments.The strong environmental migration ability of particulate matter allows EPFRs to migrate over long-distance transport,thereby impacting the quality of the local atmospheric environment.Additionally,EPFRs can also adhere to atmospheric particles and interact with typical gaseous pollutants to affect atmospheric chemical reactions.EPFRs can produce some reactive organic species,promoting oxidative stress in the human body,damaging biological macromolecules and ultimately affecting the organism health.EPFRs are considered as a novel type of pollutant that affects human health.Despite their significance,there are few literatures available on the characteristics and fate behaviors of EPFRs up to date.Therefore,supplemental reviews are crucial for providing comprehensive understanding of EPFRs.Materials and methods This review summarizes the characteristics of EPFRs in particulate matter,outlines the generation mechanism and influencing factors of EPFRs,and the impacts of EPFRs on environmental quality and organism health.Results The content of EPFRs in particulate matter ranges from 1017 to 1020 spins∙g−1.Due to the strong mobility of atmospheric particulate matter,the long-term exposure to high levels of EPFRs may aggravate the impact of particulate matter on human health.The interaction between EPFRs and typical gaseous pollutants can alter their fate and influence atmospheric chemical reactions.EPFRs are mainly produced by transition metal elements and substituted aromatic hydrocarbons through electron transfer.Additionally,the chemical bond rupture of organic substances through heat treatment or ultraviolet radiation can also produce EPFRs,and heterogeneous reactions are capable producing them as well.The production of EPFRs is not only influenced by transition metal elements and precursors,but also by various environmental factors such as oxygen,temperature,light radiation,and relative humidity.Discussion EPFRs in atmospheric particulates matters are usually rich in fine particulates with obvious seasonal and regional variations.They can easily enter the human respiratory tract and lungs with inhalable particulates,thereby increasing the risk of exposure.Additionally,EPFRs in atmospheric particulates can interact with some typical gaseous pollutants,impacting the life and fate of EPFRs in the atmosphere,and alter atmospheric chemical reactions.Traditionally,EPFRs are generated by transition metal elements and substituted aromatic hydrocarbons undergoing electron transfer in the post-flame and cool-zone regions of combustion systems and other thermal processes to remove HCl,H_(2)O or CO groups,ultimately produce semiquinones,phenoxyls,and cyclopentadienyls.Recent studies have indicated that EPFRs can also be generated under the conditions of without transition metal elemental.Organics can also produce EPFRs through chemical bond rupture during heat treatment or light radiation conditions,as well as through some heterogeneous reactions and photochemical secondary generation of EPFRs.The presence or absence of oxygen has different effects on the type and yield of EPFRs.The concentration,type,and crystal type of transition metal elements will affect the type,content,and atmospheric lifetime of EPFRs.It is generally believed that the impact of transition metal element types on EPFRs is related to the oxidation-reduction potential.The combustion temperature or heat treatment process significantly affects the type and amount of EPFRs.Factors such as precursor loading content,pH conditions,light radiation and relative humidity also influence the generation of EPFRs.EPFRs can interact with pollutants in the environment during their migration and transformation process in environmental medium.This process accelerates the degradation of pollutants and plays a crucial role in the migration and transformation of organic pollutants in environmental media.The reaction process of EPFRs may lead to the production of reactive oxygen species(ROS)such as∙OH,which can induce oxidative stress,inflammation and immune response to biological lung cells and tissues,leading to chronic respiratory and cardiopulmonary dysfunction,cardiovascular damage and neurotoxic effects,ultimately impacting the health of organisms.Conclusions The interaction mechanism between EPFRs in particulate matter and gaseous pollutants remains unclear.Furthermore,research on the generation mechanism of EPFRs without the participation of transition metals is not comprehensive,and the detection of EPFRs is limited to simple qualitative categories and lack accurate qualitative analysis.Recommendations and perspectives Further research should be conducted on the generation mechanism,measurement techniques,migration pathways,and transformation process of EPFRs.It is also important to explore the interaction between EPFRs in atmospheric particulate matter and typical gaseous pollutants. 展开更多
关键词 particulate matter(PM) environmentally persistent free radicals(EPFRs) formation mechanism influencing factors
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Microthermokinetic study of xanthate adsorption on impurity-doped galena 被引量:10
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作者 蓝丽红 陈建华 +3 位作者 李玉琼 蓝平 杨卓 艾光湧 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第1期272-281,共10页
Six kinds of galena with different impurities were synthesized and the effects of impurities on the floatability of galena were investigated. The thermodynamic and kinetic parameters on the galena surface were measure... Six kinds of galena with different impurities were synthesized and the effects of impurities on the floatability of galena were investigated. The thermodynamic and kinetic parameters on the galena surface were measured using microcalorimetry, and the adsorption configuration and energy of butyl xanthate on the surfaces of galena with different impurities were simulated by density functional theory. Flotation experiments showed that Ag and Bi significantly promoted the recovery of galena, while Zn, Sb, Mn, and Cu reduced the recovery of the flotation. Microthermokinetic results indicated that the absolute value of xanthate adsorption heat was directly proportional to the flotation recovery of galena. Adsorption heat and reaction rate coefficients of xanthate on galena containing Ag or Bi were larger than those on pure galena, but smaller on galena containing Cu or Sb. Additionally, the relationship between the heat of unsaturated adsorption of xanthate and the adsorption energy of impurity atom on galena surface was investigated. 展开更多
关键词 GALENA impurity effect floatation XANTHATE ADSORPTION MICROCALORIMETRY density functional theory
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Pathogenesis of Parkinson's disease: oxidative stress, environmental impact factors and inflammatory processes 被引量:6
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作者 袁红 郑静晨 +3 位作者 刘平 张韶峰 许建阳 白丽敏 《Neuroscience Bulletin》 SCIE CAS CSCD 2007年第2期125-130,共6页
Current hypothesis of neuronal degeneration in Parkinson's disease (PD) have been proposed, including formation of free radicals and oxidative stress, mitochondrial dysfunction, excitotoxicity, trophic factor defic... Current hypothesis of neuronal degeneration in Parkinson's disease (PD) have been proposed, including formation of free radicals and oxidative stress, mitochondrial dysfunction, excitotoxicity, trophic factor deficiency, inflammatory processes, genetic factors, environmental impact factors, toxic action of nitric oxide, apoptosis, and so on. This review mainly discussed oxidative stress, environmental impact factors, and inflammatory processes in PD. 展开更多
关键词 PATHOGENESIS Parkinson's disease oxidative stress neurogenic inflammation environmental impact
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Microstructure and defect of titanium alloy electron beam deep penetration welded joint 被引量:8
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作者 张秉刚 石铭霄 +1 位作者 陈国庆 冯吉才 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第11期2633-2637,共5页
The microstructure, phase composition and cold shut defect of thick titanium alloy electron beam welded joint were studied. The results showed that the microstructure of weld zone was composed of α′ phase; the heat ... The microstructure, phase composition and cold shut defect of thick titanium alloy electron beam welded joint were studied. The results showed that the microstructure of weld zone was composed of α′ phase; the heat affected zone was divided into fine-grained zone and coarse-grained zone, the microstructure of fine-grained zone was primary α phase + β phase + equiaxed α phase, and the microstructure of coarse-grained zone was primary α phase + acicular α′ phase; the microstructure of base metal zone basically consisted of primary α phase, and a small amount of residual β phase sprinkled. The forming. reason of cold shut was analyzed, and the precaution of cold shut was proposed. 展开更多
关键词 TA15 titanium alloy electron beam welding MICROSTRUCTURE phase composition cold shut defect weld zone heataffected zone
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Stormwater management of urban greenway in China 被引量:8
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作者 王思思 苏义敬 +2 位作者 车伍 王建龙 李俊奇 《Journal of Southeast University(English Edition)》 EI CAS 2014年第2期234-239,共6页
In order to improve the stormwater regulation functions of urban greenways on the basis of literature research and case study the relationships between urban greenway and low impact development LID and green stormwate... In order to improve the stormwater regulation functions of urban greenways on the basis of literature research and case study the relationships between urban greenway and low impact development LID and green stormwater infrastructure GSI are analyzed. Then the classification system of urban greenways is proposed based on their stormwater regulation function and the suitable technical measures for stormwater management which can be used in different kinds of greenways are selected. According to China’s urban planning system the greenway planning method combined with the urban drainage system is developed and the design methods of the greenway stormwater system and individual stormwater facilities are put forward. The relationships between the greenway stormwater system and other systems are also analyzed in terms of stormwater inlet vertical design and overflow.Finally the waterfront greenway and street greenway demonstration projects in Jiaxing City which adopts the above concept and method are introduced. The results show that the reduction rates of annual total stormwater runoff and average total runoff contaminants TSS of the stormwater system are not less than 30% and 40% respectively. 展开更多
关键词 GREENWAY stormwater management low impact development green stormwater infrastructure
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Temporal-spatial Changes in Inner Mongolian Grassland Degradation during Past Three Decades 被引量:10
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作者 张清雨 吴绍洪 +1 位作者 赵东升 戴尔阜 《Agricultural Science & Technology》 CAS 2013年第4期676-683,共8页
[Objective] This study aimed to analyze the temporal-spatial variation of Inner Mongolian grassland degradation during past three decades. [Method] The dis- tribution characteristics of grassland were described by lan... [Objective] This study aimed to analyze the temporal-spatial variation of Inner Mongolian grassland degradation during past three decades. [Method] The dis- tribution characteristics of grassland were described by land use types supervised classification with TM/ETM. Then, temporal-spatial changes of grassland coverage were quantified by the mean of maximum vegetation coverage in last 30 years. Lastly, the grassland degradation reasons were explored through statistic analysis between the grassland coverage and precipitation, temperature and grazing intensity. [Result] The grassland degradation index of Inner Mongolia was increased from 1.38 to 1.68, and the smallest was 1.28 in 2005s. Grassland degradation and improve- ment were concurrent after 1980s, but grassland degradation was the major change trend for Inner Mongolia grassland. The area of grassland degradation was enlarged from 18.08×10^4 km2 in 1980s to 22.47×10^4 km2 in 2010s on the whole and distribu- tion range was shifted from central-eastern to west in Inner Mongolia that mainly distributed on Hulun Buir and Xilin Gol grassland in 1980s and Ordos and Alax grassland in 2010s. The grassland area of degradation had a rising trend form 1980s to 1995s, then reduced to 10.8x104 km2 in 2005s, and decreased in 2010s, which mainly speared in the west of Xilin Gol grassland. [Conclusion] Inner Mongo-lian grassland degradation were become more seriously in last 30 years because that temperature, precipitation and graze intensities change, which not performance on decreasing coverage but grassland areas. 展开更多
关键词 Grassland degradation Temporal-spatial change Influencing factor Inner Mongolia
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Possible Impacts of Climate Change on Agricultural Production in China and Its Adaptation Countermeasures 被引量:10
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作者 袁彬 郭建平 +1 位作者 赵俊芳 冶明珠 《Agricultural Science & Technology》 CAS 2011年第3期420-425,共6页
Global climate warming has discernable impacts on various natural systems and biological systems. As the most fragile ecosystem,agriculture is subjected to the most direct impacts from climate change. Of these impacts... Global climate warming has discernable impacts on various natural systems and biological systems. As the most fragile ecosystem,agriculture is subjected to the most direct impacts from climate change. Of these impacts,the first one is the change in agricultural climate resources,which directly affects agricultural cultivation structure and crop variety distribution and finally results in the change in crop yield. Here,we review the advances in the impacts of climate change on crop yield,agricultural climate resources and China's agricultural cropping system and crop variety distribution pattern,and prospect the countermeasures for agricultural production in order to meet the future climate change,and several issues must be given high priority. 展开更多
关键词 Climate change Agricultural production Impact Adaptation countermeasure
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Seasonal Impact of Agricultural Non-point Source Pollution on Water Environment of Dianshan Lake Basin in Shanghai City 被引量:11
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作者 王振旗 沈根祥 +1 位作者 钱晓雍 朱英 《Agricultural Science & Technology》 CAS 2010年第7期83-86,共4页
Taken the Dalian lake region as the study area,which represents the typical agriculture production mode and agricultural non-point source pollution (ANSP) in Dianshan lake area in Shanghai City,basis on the characte... Taken the Dalian lake region as the study area,which represents the typical agriculture production mode and agricultural non-point source pollution (ANSP) in Dianshan lake area in Shanghai City,basis on the characteristics of regional ANSP and combing with the seasonal water quality monitoring of Dalian Lake and reaches of its main influents,the laws of seasonal impact on the water environment were investigated.The results showed that,the seasonal change of TN and COD concentration of regional water had no significant correlation with the local ANSP emissions,while the seasonal changes of TP was consistent with seasonal emissions of regional TP pollution,and it had a significant correlation with Chl.a in four seasons,indicating that regional TP pollutant was the constriction factor influenced the eutrophication degree of Dalian lake.Because more than 80% of TP emissions came from the drainage of intensive pounds in winter,summer and fall,TP pollutant control should be adopted as the control target of regional ANSP control. 展开更多
关键词 Dianshan Lake Non-point source pollution Seasonal effect Intensive pound
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Distribution of Rapeseed Clubroot Disease in Hubei Province and Evaluation of Yield Loss 被引量:6
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作者 任莉 贾建光 +5 位作者 李铭 刘凡 程雨贵 张明海 陈坤荣 方小平 《Agricultural Science & Technology》 CAS 2012年第4期775-777,F0003,共4页
[Objective] The aim of this study was to reveal the distribution of rapeseed clubfoot disease in Hubei Province and to assess the yield loss caused by the pathogen, Plasmodiophora brassicae. [Method] Field surveys wer... [Objective] The aim of this study was to reveal the distribution of rapeseed clubfoot disease in Hubei Province and to assess the yield loss caused by the pathogen, Plasmodiophora brassicae. [Method] Field surveys were conducted in Shayang, Dangyang, Zhijiang, Yidu and Changyang of Hubei Province during 2009- 2011. Clubfoot disease of rapeseed samples from the surveyed locations were con- firmed by PCR detection and plants infection experiment. The factors of yield and plot yields influenced by clubroot disease were determined in plot experiment. [Re- salt] Rapeseed clubroots were confirmed in Zhijiang and Dangyang and not found in Shayang and Yidu. Clubroot was found in cruciferous vegetables but not in rapeseed d in Changyang. Infection of P. brassicae significantly decreased of the first effective branch numbers of rapeseed, effective pod number per plant, seed number per pod and 1 000-grain weight. Yield of infected rapeseed decreased by 56.4% over non-infected control. [Conclusion] Rapeseed clubroot disease mainly distributed in Zhijiang and Dangyang of Hubei Province. The disease had an economic impact on rapeseed production. 展开更多
关键词 Brassica napus Plasmodiophora brassicae Occurence Economic impact
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Infrared thermography for prediction of spontaneous combustion of sulfide ores 被引量:5
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作者 李孜军 石东平 +1 位作者 吴超 王晓磊 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第12期3095-3102,共8页
The method of infrared thermography to predict the temperature of the sulfide ores has a large error. To solve this problem, the temperature of the sulfide ores is measured by thermal infrared imager and recording the... The method of infrared thermography to predict the temperature of the sulfide ores has a large error. To solve this problem, the temperature of the sulfide ores is measured by thermal infrared imager and recording thermometric instrument contrastively. The main factors, including emissivity, distance, angle and dust concentration that affect the temperature measurement precision, are analyzed. The regression equations about the individual factors and comprehensive factors are obtained by analyzing test data. The application of the regression equations improves the precision of the thermal infrared imager. The geometric information lost in traditional infrared thermometry is determined by visualization grid method and interpolation method, the relationship between the infrared imager and geometry information is established. The geometry location can be measured exactly. 展开更多
关键词 sulfide ores spontaneous combustion PREDICTION infrared thermography influent factors regression equations geometry location
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Leaf Photosynthetic Rate and Related Influencing Factors in Super High-yield Combination C Liangyou H255 被引量:8
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作者 贺安娜 吴厚雄 +2 位作者 蒋向辉 何超 徐良骏 《Agricultural Science & Technology》 CAS 2008年第2期23-25,29,共4页
[ Objective] Study on the photosynthesis and influencing factors in super high-yield combination C Liangyou H255. [ Method] The photosynthetic characteristies were measured at a hot and muggy day under natural conditi... [ Objective] Study on the photosynthesis and influencing factors in super high-yield combination C Liangyou H255. [ Method] The photosynthetic characteristies were measured at a hot and muggy day under natural conditions. [ Result] A respective single peak at 11:30 was observed in diurnal variation curves of net photosynthetic rate (Pn) and transpiration rate(Tr). Correlation analysis shows that Pn presents an extremely significant correlation with photon flux densities (PFD) of photosynthetically active radiation, in comparison assumes a significant correlation either with stomatal conductance (Gs) or with ambient CO2 concentration (Ca). [ Conclusion] Gs followed by PFD presented most influence on Pn of super high-yield combination C Liangyou H255. 展开更多
关键词 Net photosynthetic rate Diurnal variation Correlation analysis Path analysis
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Spatial and temporal variations of soil moisture in three types of agroforestry boundaries in the Loess Plateau, China 被引量:3
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作者 尤文忠 曾德慧 +3 位作者 刘明国 云丽丽 叶彦辉 张永 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第4期415-422,521,共9页
Agroforestry is a ubiquitous landscape on the slopes in Loess Plateau, where soil moisture is a limiting factor for plant growth and development. The spatial and temporal characteristics of soil moisture were studied ... Agroforestry is a ubiquitous landscape on the slopes in Loess Plateau, where soil moisture is a limiting factor for plant growth and development. The spatial and temporal characteristics of soil moisture were studied in three types of agroforestry boundaries: forest-grassland, forest-cropland and shelterbelt-cropland. The result shows that soil moisture content decreased with soil depth increasing from the surface to 110 cm. Soil moisture content differed significantly among the three boundaries all in the rainy season (July-September), dry season (May-June) and spring (March-April). The horizontal distribution of soil moisture in different soil layers in the three types of boundaries showed different patterns with line form, wave form, scoop form or "W" form. The distance of edge influence (DEI) of soil moisture in different types of landscape boundaries was estimated by variance analysis and multiple comparisons. In dry season the DEI in 0-10 cm soil layer was 0.4 H (H, average height of trees), which ranged from 0.2 H in grassland or in cropland to 0.2 H in forest field for both forest-grassland and forest-cropland boundaries, and 0.7 H (ranged from 0.2 H in cropland to 0.5 H in forest field) for shelterbelt-cropland boundary. In rainy season the DEI at soil depth of 0-110 cm was 0.7 H for the three boundaries. The results indicated that agroforestry type should be carefully selected to maintain soil moisture in land management, especially in restoring degraded land in Loess Plateau. 展开更多
关键词 distance of edge influence forest-grassland system land use soil moisture
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Feasibility assessment of LID concept for stormwater management in China through SWOT analysis 被引量:2
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作者 丁年 李子富 +3 位作者 周晓琴 胡爱兵 白晓凤 Nazim Uddin Sayed Mohammad 《Journal of Southeast University(English Edition)》 EI CAS 2014年第2期225-229,共5页
The strengths weaknesses opportunities and threats SWOT analysis method is applied to assess the feasibility of traditional stormwater management and low impact development LID in China.The results show that tradition... The strengths weaknesses opportunities and threats SWOT analysis method is applied to assess the feasibility of traditional stormwater management and low impact development LID in China.The results show that traditional stormwater management has many disadvantages e.g.only stormwater collection and discharge or flooding peak-flow regulation is taken into consideration but lack of many important functions such as on-site infiltration non-point pollution control ecological treatment etc.Meanwhile as a new stormwater management concept the LID system has many advantages e.g.LID can not only control rainwater quantity but also effectively prevent non-point pollution. Moreover LID is easy for implementation and cost effective and operation and management can also be done easily.LID has attracted more and more attention from governmental authorities at different levels and the majority of practitioners. Therefore LID has bright prospects for wide applications in China. 展开更多
关键词 stormwater management low impact development LID CONCEPT strengths weaknesses opportunities and threats SWOT analysis
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