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长叶红沙种子在萌发过程中细胞内营养物质动态研究 被引量:8
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作者 张敏 王迎春 《内蒙古大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第5期535-539,共5页
以长叶红沙种子为研究对象,经石蜡切片、染色、显微镜观察,来研究长叶红沙种子在萌发过程中营养物的动态变化,揭示长叶红沙这种旱生植物在其萌发过程中营养物消耗规律.发现长叶红沙种子中的贮藏物主要以蛋白质居多;并且萌发所需的能量... 以长叶红沙种子为研究对象,经石蜡切片、染色、显微镜观察,来研究长叶红沙种子在萌发过程中营养物的动态变化,揭示长叶红沙这种旱生植物在其萌发过程中营养物消耗规律.发现长叶红沙种子中的贮藏物主要以蛋白质居多;并且萌发所需的能量依次由胚根、胚轴和子叶中的蛋白质的分解转化成多糖而来.该项研究从一个侧面提供了对这种旱生植物的生理学资料. 展开更多
关键词 长叶红沙 种子萌发 营养物动态
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微型生态系统中鲢、鳙下行影响的实验研究——2.营养物水平 被引量:21
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作者 阮景荣 戎克文 王少梅 《湖泊科学》 EI CAS CSCD 1995年第4期334-340,共7页
鲢、鳙放养使微型生态系统的水柱氮、磷浓度和磷的分布发生了明显的变化。至实验结束时,各实验组的水柱颗粒磷、总磷和氨氮浓度都比对照组高,而正磷酸盐浓度和沉积物磷的量均低于对照组。这种变化以鳙单养系统为最大,其次是鲢、鳙混养系... 鲢、鳙放养使微型生态系统的水柱氮、磷浓度和磷的分布发生了明显的变化。至实验结束时,各实验组的水柱颗粒磷、总磷和氨氮浓度都比对照组高,而正磷酸盐浓度和沉积物磷的量均低于对照组。这种变化以鳙单养系统为最大,其次是鲢、鳙混养系统,鲢单养系统的变化最小。微型生态系统中正磷酸盐浓度同浮游动、植物密度和初级生产力显著相关,氨氮浓度同所述变量之间的相关关系则多半与正磷酸盐相反。实验观测期间浮游植物密度与总磷浓度之间存在营养级联假说所预见的下行影响,实验结束时二者之间却有上行影响的趋向。根据实验观测结果认为,微型生态系统营养物(尤其是磷)水平的变动,主要是鲢、鳙的摄食改变了系统的群属结构和代谢强度的结果,同时反映了实验鱼对系统中营养物再生的影响。 展开更多
关键词 微型生态系统 营养物动态 磷酸盐
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Design and Research on Artificial Rumen Continuous Culture System
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作者 孟宪章 李敏 +2 位作者 施继红 胡晓丽 刘庆福 《Agricultural Science & Technology》 CAS 2012年第11期2445-2448,共4页
[Objective] The paper was to study the dynamic changes of forage nutrient substance fermentation in rumen, and a set of continuous culture system of artificial rumen was designed. [Method] With in vivo as control, the... [Objective] The paper was to study the dynamic changes of forage nutrient substance fermentation in rumen, and a set of continuous culture system of artificial rumen was designed. [Method] With in vivo as control, the simulating rumen fer- mentation effect in vitro culture system was evaluated. [Result] The simulation rumen fermentation test needed adaptive phase of 2-3 d, and the fermentation state was relatively stable within 3-9 d, with good effects. The test showed certain regularity variation with index value of rumen in vivo. [Conclusion] The continuous culture sys- tem of artificial rumen could be used as the ideal model to study the rumen fermen- tation in vivo. 展开更多
关键词 Rumen fermentation Continuous culture system Experimental research Effect evaluation
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Food preferences by birds using bird-feeders in winter: a large-scale experiment
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作者 Piotr Tryjanowski Anders Pape Moiler +3 位作者 Federico Morelli Piotr Indykiewicz Piotr Zduniak Lukasz Myczko 《Avian Research》 CSCD 2018年第2期157-162,共6页
Background: Intentional winter bird feeding in gardens is one of the most common interactions between birds and humans. Because feeding may have both desired effects(provisioning of nutritious food for under-nourished... Background: Intentional winter bird feeding in gardens is one of the most common interactions between birds and humans. Because feeding may have both desired effects(provisioning of nutritious food for under-nourished birds) and undesired effects(favouritism of competitively superior species, transmission of disease), management of supplementary sites should be optimized from an ecological and conservation perspective. Therefore, the main aim of this study was to experimentally test winter food preferences of birds, with underlying potential influence of habitat(rural vs. urban) on realised food preferences pattern.Methods: We conducted an experimental analysis of food preferences of wintering birds by provided bird-feeders in urban and rural environments across Poland. Data were collected twice during winter 2013–2014 across Poland, in total with 80 experimental trials.Results: Sunflower seeds were the most preferred food supplement both in urban and rural habitats, significantly more exploited than any other food simultaneously available in feeders(animal fat, millet seed and dry fruits of rowanberry). However, no significant differences were recorded between urban and rural habitats in use of food.Conclusions: The degree of use of a particular type of food at bird-feeders depended on the overall use of food in a bird-feeder—consumption of each of the four types of food was significantly positively correlated with that of the others, and it was positively correlated with the number of birds observed at the feeders. 展开更多
关键词 BIRD Food preferences Human-animal interactions Supplementary food WINTER
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