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热带西太平洋部分海域海水的化学状况分析
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作者 宋金明 《海洋环境科学》 CAS CSCD 北大核心 1996年第3期15-21,共7页
本文对1992年11月棉兰老岛东南海域、伊里安岛北部海域上层水及40°S156°E定点长达4个月的pH、Eh、∑S(-Ⅱ)调查分析,研究了上述海域的海水化学状况,结果表明,1992年11月,在上层水中(0~1... 本文对1992年11月棉兰老岛东南海域、伊里安岛北部海域上层水及40°S156°E定点长达4个月的pH、Eh、∑S(-Ⅱ)调查分析,研究了上述海域的海水化学状况,结果表明,1992年11月,在上层水中(0~150m),棉兰老岛东南海域海水的碱性较弱、氧化性较强,伊里安岛北部海域海水碱性较强,还原性较强,4°S156°E的上层水界于二者之间;在4°S156°E海水中,50m左右是一层碱性最强的海水,其pH≥8.30,300m以下pH则在7.80~7.90之间,碱性较弱,50~200m是Eh、∑S(-Ⅱ)的跃层区,Eh变为低值,∑S(-Ⅱ)变为高值,该层海水的还原性最强;在其光层内,pH一般在中午12:00出现最大值,凌晨4:00出现最低值,下午4:00一般出现Eh最低值,∑S(-Ⅱ)的最高值,这时海水的还原性最强;在其光层内,浮游植物的光合作用是控制海水碱度的主要因素,海气界面的氧交换是控制海水氧化还原的重要因素,温度是决定海水中∑S(-Ⅱ)产生的重要因素之一。 展开更多
关键词 热带西太平洋 碱度 氧化还原特性 海水 化学状况
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高中生化学交流活动状况与学业水平相关性分析 被引量:1
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作者 皇甫倩 王后雄 《课程.教材.教法》 CSSCI 北大核心 2013年第10期80-87,共8页
我们从化学交流意识、化学交流方式、化学交流障碍以及化学交流效果四个维度对高中学优生、学中生和学困生交流状况进行调查分析。改善当前化学交流现状的途径主要包括营造和谐化学交流氛围,加强化学交流意识;创设别样化学交流情境,拓... 我们从化学交流意识、化学交流方式、化学交流障碍以及化学交流效果四个维度对高中学优生、学中生和学困生交流状况进行调查分析。改善当前化学交流现状的途径主要包括营造和谐化学交流氛围,加强化学交流意识;创设别样化学交流情境,拓展化学交流方式;构建开放化学交流体系,克服化学交流障碍以及倡导多元化学交流评价,提升化学交流效果四种途径。 展开更多
关键词 高中生 化学交流活动状况 调查分析
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高师生化学实验状况的调查研究 被引量:1
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作者 韦斯林 黄瓅 沈丹玲 《高校实验室工作研究》 2007年第2期92-96,共5页
针对当前高校师范生化学实验存在的种种问题,结合实际以及有关文献资料,自编调查问卷,抽样调查320名化学师范生,内容涉及化学实验心向、实验习惯、自主探究三个方面。利用SPSS11.0统计软件对调查结果进行统计处理,深入分析了当前高师生... 针对当前高校师范生化学实验存在的种种问题,结合实际以及有关文献资料,自编调查问卷,抽样调查320名化学师范生,内容涉及化学实验心向、实验习惯、自主探究三个方面。利用SPSS11.0统计软件对调查结果进行统计处理,深入分析了当前高师生化学实验状况,并提出了相应的教学建议。 展开更多
关键词 化学实验状况 高师生 问卷调查 教学建议
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山东保护地蔬菜化学污染状况及解决的途径
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作者 何启伟 李琳 《山东蔬菜》 1998年第4期8-11,共4页
蔬菜是人们生活中维生素、矿物质、碳水化合物和其他营养物质的重要来源。随着经济的发展和生活水平的提高,蔬菜供应和消费状况正在成为衡量一个国家或地区生活水平高低的重要标志之一。同时,由于工业废弃物排放增加,环境污染日趋严重,... 蔬菜是人们生活中维生素、矿物质、碳水化合物和其他营养物质的重要来源。随着经济的发展和生活水平的提高,蔬菜供应和消费状况正在成为衡量一个国家或地区生活水平高低的重要标志之一。同时,由于工业废弃物排放增加,环境污染日趋严重,以及化肥农药用量越来越大,蔬菜产品污染问题也日益引起广大消费者的担心和关注。生产高质量、无污染、安全、新鲜、多样化的蔬菜,并逐步实现小包装净菜上市、周年均衡供应,成为市场和消费者期盼蔬菜产业达到的奋斗目标。因此,研究提出科学、可行的配套技术,努力实现这个奋斗目标,已经成为蔬菜科技工作者和生产者义不容辞的责任和神圣的任务。 展开更多
关键词 山东 蔬菜 化学污染状况 保护地蔬菜
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全国土地质量地球化学调查二十年 被引量:72
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作者 李括 彭敏 +12 位作者 赵传冬 杨柯 周亚龙 刘飞 唐世琪 杨帆 韩伟 杨峥 成晓梦 夏学齐 关涛 骆检兰 成杭新 《地学前缘》 EI CAS CSCD 北大核心 2019年第6期128-158,共31页
土地质量地球化学调查计划是我国继区域化探全国扫面计划之后一个新的国家地球化学填图计划,该计划实施20年来,在支撑土壤环境污染防控、土地资源管理、国家重大立法、精准扶贫等方面做出了重大贡献,显著拓展了地质工作服务链。本文从... 土地质量地球化学调查计划是我国继区域化探全国扫面计划之后一个新的国家地球化学填图计划,该计划实施20年来,在支撑土壤环境污染防控、土地资源管理、国家重大立法、精准扶贫等方面做出了重大贡献,显著拓展了地质工作服务链。本文从计划的提出背景、项目的组织实施、主要进展、调查技术的进步和分析测试技术的提高与质量控制方案的完善等方面回顾了该计划的发展历程。从全国耕地地球化学状况、全国省会城市土壤环境质量状况、中国主要淡水湖泊沉积物环境质量状况、中国主要农耕区20年来土壤碳库变化4个方面对调查成果做了全面总结。全方位介绍了调查应用成果在土地管理、土壤污染防治、农业种植结构调整、脱贫攻坚、地方病防治、油气勘查、固体矿产勘查等7个领域中的应用。并在调查技术革新、评价方法创新和调查与研究融合三个方面对土地质量地球化学调查工作的未来发展趋势做了展望。 展开更多
关键词 土地质量地球化学调查 全国耕地地球化学状况 全国省会城市土壤环境质量状况 中国主要淡水湖泊沉积物环境质量状况 中国主要农耕区20年来土壤碳库变化
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大棚土壤的理化状况和微生物状况 被引量:16
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作者 张昌爱 毕军 +3 位作者 夏光利 张萍 史桂芳 朱国梁 《安徽农业科学》 CAS 2002年第2期275-276,共2页
对保护地的物理状况、化学状况及微生物状况作一介绍和总结 ,旨在为保护地的施肥。
关键词 土壤化学状况 土壤微生物状况 蔬菜 保护地栽培 土壤物理状况
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高中化学实验情况调查分析 被引量:1
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作者 高雅西 《学周刊(下旬)》 2015年第1期36-36,共1页
本文选取HLZ中学172名高中学生为研究对象,运用SPSS统计软件,对高中生化学实验情况进行了因素分析。并且根据所得结果对学生的填表情况采取了相应的应对措施。
关键词 高中化学实验状况 因素分析 应对措施
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论森林采伐作业对土壤理化性质的影响 被引量:8
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作者 赵康 孙长仁 《内蒙古林学院学报》 1997年第4期101-107,共7页
土壤是生态系统最基本的资源,也是不可再生的物理组分,各类经营活动必须以维护土壤的持续利用为前提。森林采伐作业不可避免地会对森林生态系统产生一定的扰动。其中最为主要的方面是采伐作业后林地土壤理化性质的改变。本文从生态学... 土壤是生态系统最基本的资源,也是不可再生的物理组分,各类经营活动必须以维护土壤的持续利用为前提。森林采伐作业不可避免地会对森林生态系统产生一定的扰动。其中最为主要的方面是采伐作业后林地土壤理化性质的改变。本文从生态学的原理出发,阐述了采伐作业引起土壤理化性质改变的机理,并分析了这些变化对森林生长和森林生态系统经营的影响。 展开更多
关键词 土壤 森林采伐 物理性能 化学状况
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夏季受孕或使后代较不健康
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《养猪》 2019年第4期64-64,共1页
【英国《泰晤士报》网站7月10日报道】题:母亲在夏天受孕的孩子可能较不健康瑞士研究人员发现,在10月到次年2月怀上的胎儿更可能拥有有益的“褐色”脂肪。这种脂肪会燃烧卡路里,而不是储藏卡路里。小鼠实验提示,这可能是因为寒冷会微妙... 【英国《泰晤士报》网站7月10日报道】题:母亲在夏天受孕的孩子可能较不健康瑞士研究人员发现,在10月到次年2月怀上的胎儿更可能拥有有益的“褐色”脂肪。这种脂肪会燃烧卡路里,而不是储藏卡路里。小鼠实验提示,这可能是因为寒冷会微妙地改变精子中基因周围的化学状况,从而使得此时孕育的后代吃得更多,但体重增加较少。很难说睾丸要处于寒冷温度中多长时间才会发生这种效应,但小鼠研究显示,时间或许不足一天。 展开更多
关键词 健康 后代 受孕 夏季 《泰晤士报》 研究人员 化学状况 体重增加
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春季果园巧管理
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《绿色科技》 2010年第3期50-50,共1页
1.春耕保墒:为给果树根系生长创造良好条件,应急时进行果园春季耕翻,改善土壤物理化学状况。方法有二:①顶凌刨树埯,②果树行间耕翻。
关键词 果园 管理 根系生长 化学状况 土壤物理 果树 耕翻 保墒
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畜牧综合体废弃物对潜水和地表水的影响
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作者 А.Ю.Беляев Р.Г.Джамалов +4 位作者 В.Л.Элобина Ю.А.Медовар И.О.Юшманов 宋清(翻译) 苑惠明(校对) 《水文地质工程地质技术方法动态》 2009年第3期20-20,21-26,共7页
研究探讨了邻接火型畜牧综合体区域的水文地质和水化学状况的变化;对环境可能受到的污染做了预测,并且论证了环境保护措施。
关键词 地表水 综合体 畜牧 废弃物 环境保护措施 潜水 化学状况 水文地质
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春季果园巧管理
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《绿色科技》 2015年第4期319-319,共1页
1.春耕保墒:为给果树根系生长创造良好条件,应急时进行果园春季耕翻,改善土壤物理化学状况。方法有二:一是顶凌刨树埯,二是果树行间耕翻。 2.适时春灌:春季果树抽枝展叶、开花坐果需要消耗大量水分,应根据土壤含水量进行春灌,以补... 1.春耕保墒:为给果树根系生长创造良好条件,应急时进行果园春季耕翻,改善土壤物理化学状况。方法有二:一是顶凌刨树埯,二是果树行间耕翻。 2.适时春灌:春季果树抽枝展叶、开花坐果需要消耗大量水分,应根据土壤含水量进行春灌,以补充土壤水分的不足。华北地区3月中下旬到4月上旬春灌,灌水量以浸透果树耕作层为佳。 展开更多
关键词 果园 管理 土壤水分 土壤含水量 根系生长 化学状况 土壤物理 开花坐果
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春季果园巧管理
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《绿色科技》 2015年第2期196-196,共1页
1.春耕保墒:为给果树根系生长创造良好条件,应急时进行果园春季耕翻,改善土壤物理化学状况。方法有二:一是顸凌刨树埯,二是果树行间耕翻。2.适时春灌:春季果树抽枝展叶、开花坐果需要消耗大量水分,应根据土壤含水量进行春灌,... 1.春耕保墒:为给果树根系生长创造良好条件,应急时进行果园春季耕翻,改善土壤物理化学状况。方法有二:一是顸凌刨树埯,二是果树行间耕翻。2.适时春灌:春季果树抽枝展叶、开花坐果需要消耗大量水分,应根据土壤含水量进行春灌,以补充土壤水分的不足。 展开更多
关键词 果园 管理 土壤水分 土壤含水量 根系生长 化学状况 土壤物理 开花坐果
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Skarn mineralogy and its geological significance for the Tayuan (Cu-Mo)-Pb-Zn deposit, northern Daxinganling metallogenic belt 被引量:4
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作者 Chao Li Tao Ren +4 位作者 Jian-Guo Huang Run-Sheng Han He-Jun Yin Hong-Yang Zhou Zhi-Hong Feng 《Acta Geochimica》 EI CAS CSCD 2017年第1期89-101,共13页
The Tayuan(Cu-Mo)-Pb-Zn deposit is located in the northern part of Daxinganling,NE China.Lenticular ore body occurs in the skarn zone.The skarn minerals mainly include garnet,pyroxene,epidote and wollastonite.Electron... The Tayuan(Cu-Mo)-Pb-Zn deposit is located in the northern part of Daxinganling,NE China.Lenticular ore body occurs in the skarn zone.The skarn minerals mainly include garnet,pyroxene,epidote and wollastonite.Electron microprobe analysis shows that the end member of garnet is mainly andradite(Ad_(62-97)Gr_(11-45),the pyroxene is mainly diopside,and epidote is mainly clinozoisite.These characteristics indicate that the Tayuan polymetallic skarn deposit is mainly calcareous skarn.Sometimes the content zonation can be observed in garnets.With one garnet crystal,content is shifty from the core to the rim.In general,the iron content in the core is higher than in the edge.The content in the garnet shows that the garnet in the Tayuan deposit formed from weak oxidation in alkaline environment with the oxygen fugacity increasing,suggesting that the hydrothermal fluid evolved from an acidic to a slight alkaline state.In the Tayuan polymetallic deposit,the ratio of Mn/Fe in pyroxene is about 1.3,and of Mg/Fe,it is about 2.The components of garnet in the Tayuan deposit plot in the field of the typical skarn Zn,Cu,Mo deposits in the world. 展开更多
关键词 Skarn minerals (Cu Mo) Pb Zn deposit Physical chemical condition Tayuan
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A niche model to predict Microcystis bloom decline in Chaohu Lake, China 被引量:2
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作者 汪志聪 李钟杰 李敦海 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第4期587-594,共8页
Cyanobacterial blooms occur frequently in lakes due to eutrophication. Although a number of models have been proposed to forecast algal blooms, a good and applicable method is still lacking. This study explored a simp... Cyanobacterial blooms occur frequently in lakes due to eutrophication. Although a number of models have been proposed to forecast algal blooms, a good and applicable method is still lacking. This study explored a simple and effective mathematical-ecological model to evaluate the growth status and predict the population dynamics of Microcystis blooms. In this study, phytoplankton were collected and identified from 8 sampling sites in Chaohu Lake every month from July to October, 2010. The niche breadth and niche overlap of common species were calculated using standard equations, and the potential relative growth rates of Microcystis were calculated as a weighted-value of niche overlap. In July, the potential relative growth rate was 2.79 (a.u., arbitrary units) but then rapidly declined in the following months to -3.99 a.u. in September. A significant correlation (R=0.998, P<0.01) was found in the model between the net-increase in biomass of Microcystis in the field and the predicted values calculated by the niche model, we concluded that the niche model is suitable for forecasting the dynamics of Microcystis blooms. Redundancy analysis indicated that decreases in water temperature, dissolved oxygen and total dissolved phosphorus might be major factors underlying bloom decline. Based on the theory of community succession being caused by resource competition, the growth and decline of blooms can be predicted from a community structure. This may provide a basis for early warning and control of algal blooms. 展开更多
关键词 Microcystis bloom niche breadth niche overlap predictive model Chaohu Lake
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Avocado Nutritional Diagnosis (Persea americana Mill.) "Hass", Soil Fertility and Water Quality in Ocuituco, Morelos
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作者 Hector Sotelo-Nava Oscar Gabriel Villegas-Torres +6 位作者 Martha Lilia Dominguez-Patint Elias Hernfindez Castro Agustin Damian Nava Antonio Rodrlguez-Martmez Carlos Manuel Acosta-Duran Maria Andrade-Rodriguez Iran Alia-Tej acal 《Journal of Chemistry and Chemical Engineering》 2013年第11期1068-1073,共6页
Morelos is the fourth in area cultivated and production volume of avocado. Of the 13 municipalities where it is farmed, Ocuituco represents 43.51% and Tetela del Volain 27.53%. Despite being one of the main fruit spec... Morelos is the fourth in area cultivated and production volume of avocado. Of the 13 municipalities where it is farmed, Ocuituco represents 43.51% and Tetela del Volain 27.53%. Despite being one of the main fruit species in Morelos, no information related to the fertility of the soil where it is grown, the quality of water available for irrigation and nutritional status of this important fruit for the state. The study was conducted in the municipality of Ocuituco which identified three agro-habitats taking into account climate, landform, soil type and altitude. In each agro-habitat were carried out soil sampling to determine the physical and chemical characteristics based on the Mexican Official Standard NOM-021-SEMARNAT-2000, the chemical quality of water for irrigation as described by Richards (1954) and crop nutrient status of avocado "Hass" according to the methodology described by Maldonado (2002). The soils had different physical and chemical characteristics, as well as the nutritional status of avocado trees in the three agro-habitats. The trees had excessive concentration of CI, Cu and Zn. Indices of optimal percentage deviation expressed different nutritional requirements. The water used for irrigation was of low salinity and sodium content, so it can be used without restrictions. 展开更多
关键词 Soil fertility water quality nutrients Hass.
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Water Status in Baghdad 被引量:1
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作者 Dheyaa Wajid Abbood Yasir Talib Hameed Safaa Nasser Hassan 《Journal of Environmental Science and Engineering(B)》 2012年第5期593-599,共7页
Water is a strategically limited natural resource, and currently Iraq is in the grip of an extended drought period. It is needed to look for alternative water sources and work towards achieving high level of sustainab... Water is a strategically limited natural resource, and currently Iraq is in the grip of an extended drought period. It is needed to look for alternative water sources and work towards achieving high level of sustainability. Measurements for gray water samples were carried out including pH, EC (electrical conductivity), TDS (total dissolved solids), TS (total solids), TSS (total suspended solids), DO (dissolved oxygen), BOD5 (biochemical oxygen demand), COD (chemical oxygen demand), alkalinity, chlorides (Cl), calcium (Ca), sodium (Na), magnesium (Mg), potassium (K), lead (Pb), TC (total coliforms), TF (total fecal coliforms), and nitrate (NO3). The goals of this study are to estimate quantities of fresh water consumption and gray water generated in typical Baghdadian households, and to investigate gray water quality (physical, chemical and biological). The major results can be summarized as follows: (1) The daily water consumption in Baghdad ranged from 75 Lpcd to 176 Lpcd with an average of 116 Lpcd; (2) the maximum daily consumption in Baghdad ranged from 124 Lpcd to 327 Lpcd with an average of 186 Lpcd; (3) the maximum hourly consumption in Baghdad ranged from 154 Lpcd to 900 Lpcd with an average of 308 Lpcd; (4) gray water generation in Baghdad ranged from 34 Lpcd to 139 Lpcd with an average of 68 Lpcd, and that gray water generated constituted 58% to 72% of total consumption. 展开更多
关键词 Water saving water quality water consumption Baghdad gray water.
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Characterizations of Abandoned Peatlands from Acadian Peninsula: Agro-ecologic and Environmental Value-Added Alternatives
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作者 Mathieu Quenum Papa Malick Sall Marion Tetegan 《Journal of Environmental Science and Engineering(B)》 2014年第4期190-204,共15页
In the northeast region of New Brunswick, the majority of peatlands are mainly used for horticultural purposes. Abandoned peatlands after peat extraction could represent one of the most important ecological resources ... In the northeast region of New Brunswick, the majority of peatlands are mainly used for horticultural purposes. Abandoned peatlands after peat extraction could represent one of the most important ecological resources through their remaining substrates: serving as agronomic, ecological or environmental value-added support to local development; and giving a second economic life to peatlands. To evaluate this innovative peat soil management, a study was conducted on three residual peatlands from the Acadian Peninsula. Their status was described through a physic-chemical characterization. The results suggest that the peat thickness and the mineral horizon characteristics are good indicators to identify these post-harvest peat soils. The studied sites were characterized by a flat topography, poor and unequal drainage inducing a variation of the water table level. The peat thickness ranged from 18 cm to 40 cm, while the thickness of the mineral horizon--mostly sandy--ranged between 20 cm and 30 cm. The chemical properties revealed an electrical conductivity above 50 μS·cm^-1, an acid pH, and a variable cation exchange capacity (1.3 cmolc·kg^-1 to 11.4 cmolc·kg^-1). This preliminary study gives basic knowledge on Acadian Peninsula abandoned peatlands soils and gives information about the conditions of their agro-economic, ecological and/or environmental management. 展开更多
关键词 BOGS survey soil properties agronomic potential New Brunswick.
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Borderline Products between Bio-fertilizers/ Bio-effectors and Plant Protectants: The Role of Microbial Consortia
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作者 Marco Nuti Giusto Giovannetti 《Journal of Agricultural Science and Technology(A)》 2015年第5期305-315,共11页
In the delicate normative balance, at European Union (EU) level of the borderline products (i.e., between plant protectants and bio-fertilizers/bio-effectors) containing microbial consortia (MC) instead of singl... In the delicate normative balance, at European Union (EU) level of the borderline products (i.e., between plant protectants and bio-fertilizers/bio-effectors) containing microbial consortia (MC) instead of single microbial strains, the most relevant factors influencing the categorization of the products are the intention of use, the cell density and the mode of action. For the latter, the basic difference between the two types of products is that a plant protectant has a targeted activity on plant pathogens, while a bio-fertilizer acts indirectly by nourishing and fortifying the host plant (healthier plant), thus inducing a generalized resistance to the onset of pathological status, irrespective of its origin and nature. Case-studies are presented on the effectiveness of MC as bio-fertilizers/bio-effectors on different crops. Bio-fertilizers exhibit a double effect--biotic and abiotic, leading to the fortification of the crop plant linked to its more effective water and nutrient uptakes as well asto a generalized healthier status. This in turn leads to a higher resistance to diseases. In addition, bio-fertilizers play a relevant role on the reduction of environmental impacts due to chemical fertilizers, e.g., by facilitating the uptake of phosphorus (P), thus reducing the need of P fertilization. Although finding a scientifically-based balance between regulatory need and marketing constraint is not always an easy task, the availability of scientific advancements combined to common sense should help in describing positive effects and risk profiles of MC in agriculture. 展开更多
关键词 Bio-fertilizers/bio-effectors plant protection products MC.
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Physical Activity Stares of Civil Servants and Their Health- Related Research
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作者 Yicheng ZHOU Suhua BI +1 位作者 Qingle LIU Jianyun Bao 《International Journal of Technology Management》 2014年第11期16-18,共3页
Since the 1980s, people' s material and spiritual life are constantly enriched and improved. People' s values are constantly changing, more and more people realize that participate in physical exercise for their own... Since the 1980s, people' s material and spiritual life are constantly enriched and improved. People' s values are constantly changing, more and more people realize that participate in physical exercise for their own importance in sports. The status of people' s lives has been greatly improved, for most residents; they participate in physical activity and have gradually become a richer cultural life, and they enhance the basic needs of physical, mental lifelong sports have gradually deep heart. While people continue to enhance the sports consciousness exercise, we also see some potential problems, such as the rapid development of science and technology is to bring more and more problems to people. As people, enjoy the level of automation in the material aspects of life. They gradually have cars, telephones, washing machines, refrigerators, microwave ovens, rice cookers. And the household products go into our lives, we enjoy the material on those by making more and more people gradually reduce the daily activities. And the most prominent is the elevators and cars, reducing active time and the amount of activity, a lot of heat stored in the human body is causing various diseases, from the results of medical research over the past decade. Various diseases associated with obesity have been become the most important factor in human deaths worldwide, the rapid emergence of this disease and the rapid development of social science and technology form a clear lack of coordination, for which many experts at home and abroad for such issues of deep study and research. 展开更多
关键词 Civil Servants Physical Activity HEALTH
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