Name: fluorescently labeled bacteria as a tracer to reveal novel pathways of organic carbon flow in aquatic ecosystems
Uploaded: 2019-09-13T14:00:00
Description: Watch this Scientific Journal Video about Fluorescently Labeled Bacteria as a Tracer to Reveal Novel Pathways of Organic Carbon Flow in Aquatic Ecosystems at JoVE.com

这项研究得到了捷克科学基金会的支持，分别向K.和D.S.颁发了13-00243S和19-16554S的研究补助金。本文还得到由欧洲区域发展基金资助的"生物操作作为改善水坝水库水质的工具"项目（无CZ.02.1.01/0.0/0.0/0.0/16_025/0007417）项目的支持，该项目由欧洲区域发展基金资助，用于业务方案研究、开发和教育。

1. 样本收集
<ol><li>
水库水样收集：第一个案例研究（Exp I;低天然原位捕食者和猎物丰度系统）<ol>
<li>以适当的深度从所需位置收集水样。在运送到实验室过程中，将样品保存在温度控制的冷却器中，在原位温度下填充（避免温度冲击;应注意，原生动物的吸收率取决于温度）。 注：我们的取样是在中富营养峡谷形的切莫夫水库（南波希米亚，体积34.5 x 106 m3，最大?...

<ol>
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S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selective+feeding+behaviour+of+key+free-living+protists:+avenues+for+continued+study.">Selective feeding behaviour of key free-living protists: avenues for continued study.</a> Aquatic Microbial Ecology. 53, 83-98 (2008).</li><li>Kirchman, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Processes in Microbial Ecology. 2nd Edition. , (2018).</li><li>Porter, K. G., Feig, Y. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+use+of+DAPI+for+identifying+and+counting+aquatic+microflora.">The use of DAPI for identifying and counting aquatic microflora.</a> Limnology and Oceanography. 25, 943-948 (1980).</li><li>Foissner, W., Berger, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+user-friendly+guide+to+the+ciliates+(Protozoa,+Ciliophora)+commonly+used+by+hydrobiologists+as+bioindicators+in+rivers,+lakes,+and+waste+waters,+with+notes+on+their+ecology.">A user-friendly guide to the ciliates (Protozoa, Ciliophora) commonly used by hydrobiologists as bioindicators in rivers, lakes, and waste waters, with notes on their ecology.</a> Freshwater Biology. 35, 375-482 (1996).</li><li>Foissner, W., Berger, H., Schaumburg, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+and+ecology+of+limnetic+plankton+ciliates.">Identification and ecology of limnetic plankton ciliates.</a> Informationsberichte des Bayer Landesamtes f&#252;r Wasserwirtschaft Heft. , 3-99 (1999).</li><li>&#352;imek, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ciliate+grazing+on+picoplankton+in+a+eutrophic+reservoir+during+the+summer+phytoplankton+maximum:+a+study+at+the+species+and+community+level.">Ciliate grazing on picoplankton in a eutrophic reservoir during the summer phytoplankton maximum: a study at the species and community level.</a> Limnology &amp; Oceanography. 40, 1077-1090 (1995).</li><li>Skibbe, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+improved+quantitative+protargol+stain+for+ciliates+and+other+planktonic+protists.">An improved quantitative protargol stain for ciliates and other planktonic protists.</a> Archiv f&#252;r. Hydrobiolgie. 130, 339-347 (1994).</li><li>Macek, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Growth+rates+of+dominant+planktonic+ciliates+in+two+freshwater+bodies+of+different+trophic+degree.">Growth rates of dominant planktonic ciliates in two freshwater bodies of different trophic degree.</a> Journal of Plankton Research. 18, 463-481 (1996).</li><li>Šimek, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microbial+food+webs+in+hypertrophic+fishponds:+omnivorous+ciliate+taxa+are+major+protistan+bacterivores.">Microbial food webs in hypertrophic fishponds: omnivorous ciliate taxa are major protistan bacterivores.</a> Limnology &amp; Oceanography. , (2019).</li><li>Jezbera, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Major+freshwater+bacterioplankton+groups:+Contrasting+trends+in+distribution+of+Limnohabitans+and+Polynucleobacter+lineages+along+a+pH+gradient+of+72+habitats.">Major freshwater bacterioplankton groups: Contrasting trends in distribution of Limnohabitans and Polynucleobacter lineages along a pH gradient of 72 habitats.</a> FEMS Microbiology Ecology. 81, 467-479 (2012).</li><li>Kasalick&#253;, V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+diversity+of+the+Limnohabitans+genus,+an+important+group+of+freshwater+bacterioplankton,+by+characterization+of+35+isolated+strains.">The diversity of the Limnohabitans genus, an important group of freshwater bacterioplankton, by characterization of 35 isolated strains.</a> PLoS One. 8, 58209 (2013).</li><li>Stabell, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ciliate+bacterivory+in+epilimnetic+waters.">Ciliate bacterivory in epilimnetic waters.</a> Aquatic Microbial Ecology. 10, 265-272 (1996).</li><li>Zingel, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ciliates+are+the+dominant+grazers+on+pico-+and+nanoplankton+in+a+shallow,+naturally+highly+eutrophic+lake.">Ciliates are the dominant grazers on pico- and nanoplankton in a shallow, naturally highly eutrophic lake.</a> Microbial Ecology. 53, 134-142 (2007).</li><li>Bickel, S. L., Tang, K. W., Grossart, H. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ciliate+epibionts+associated+with+crustacean+zooplankton+in+german+lakes:+distribution,+motility,+and+bacterivory.">Ciliate epibionts associated with crustacean zooplankton in german lakes: distribution, motility, and bacterivory.</a> Frontiers in Microbiology. 3 (243), (2012).</li><li>Sirov&#225;, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hunters+or+gardeners?+Linking+community+structure+and+function+of+trap-associated+microbes+to+the+nutrient+acquisition+strategy+of+a+carnivorous+plant.">Hunters or gardeners? Linking community structure and function of trap-associated microbes to the nutrient acquisition strategy of a carnivorous plant.</a> Microbiome. 6, 225 (2018).</li><li>&#352;imek, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ecological+traits+of+a+zoochlorellae-bearing+Tetrahymena+sp.+(Ciliophora)+living+in+traps+of+the+carnivorous+aquatic+plant+Utricularia+reflexa.">Ecological traits of a zoochlorellae-bearing Tetrahymena sp. (Ciliophora) living in traps of the carnivorous aquatic plant Utricularia reflexa.</a> Journal of Eukaryotic Microbiology. 64, 336-348 (2017).</li><li>Pitsch, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+green+Tetrahymena+utriculariae+n.+sp.+(Ciliophora,+Oligohymenophorea)+with+its+endosymbiotic+algae+(Micractinium+sp.),+living+in+the+feeding+traps+of+a+carnivorous+aquatic+plant.">The green Tetrahymena utriculariae n. sp. (Ciliophora, Oligohymenophorea) with its endosymbiotic algae (Micractinium sp.), living in the feeding traps of a carnivorous aquatic plant.</a> Journal of Eukaryotic Microbiology. 64, 322-335 (2017).</li><li>Nielsen, J. M., Clare, E. L., Hayden, B., Brett, M. T., Kratina, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diet+tracing+in+ecology:+Method+comparison+and+selection.">Diet tracing in ecology: Method comparison and selection.</a> Methods in Ecology and Evaluation. 9, 278-291 (2018).</li><li>Beisner, B. E., Grossart, H. P., Gasol, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+guide+to+methods+for+estimating+phago-mixotrophy+in+nanophytoplankton.">A guide to methods for estimating phago-mixotrophy in nanophytoplankton.</a> Journal of Plankton Research. , 1-13 (2019).</li><li>Dolan, J. D., &#352;imek, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Processing+of+ingested+matter+in+Strombidium+sulcatum,+a+marine+ciliate+(Oligotrichida).">Processing of ingested matter in Strombidium sulcatum, a marine ciliate (Oligotrichida).</a> Limnology and Oceanography. 42, 393-397 (1997).</li><li>Massana, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Grazing+rates+and+functional+diversity+of+uncultured+heterotrophic+flagellates.">Grazing rates and functional diversity of uncultured heterotrophic flagellates.</a> The ISME Journal. 3, 588-596 (2009).</li><li>Gruj&#269;i&#263;, V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cryptophyta+as+major+freshwater+bacterivores+in+experiments+with+manipulated+bacterial+prey.">Cryptophyta as major freshwater bacterivores in experiments with manipulated bacterial prey.</a> The ISME Journal. 12, 1668-1681 (2018).</li></ol>

在水生系统中破译营养相互作用总是具有挑战性的28，特别是在纳米浮游生物秤涉及原发动物和他们的猎物，细菌。在营养摄入途径和定量方面，由于生物相互作用的复杂性高，在高营养水平下成功使用的方法的应用的可能性较小。例如，这些方法包括稳定的同位素标记方法。该协议显示了使用荧光显微镜和荧光标记细菌作为示踪剂来跟踪和半定量/估计碳流动的优点（细菌猎物?...

异养原核生物是水生系统中的关键生物成分，在浮游生物生物量1、2、3中占很大比例。控制其丰度、多样性和活性的因素对于理解其在生物地球化学循环中的作用（即有机碳和其他营养物质的命运以及从原核生物到更高的营养水平的能量流动）至关重要。原生动物放牧是这些重要因素之一。异营养纳米旗和纤毛的细菌对原核生物丰度、群落功能、结构、多样性，甚至细胞形态和特定细菌群的生长速率施加了强大的自上而下的控制。 5，6.在一些系统中，原发学家是细菌死亡的主要原因6，7。
用于评估原生动物细菌的标准方法，已经使用了一段时间，涉及使用荧光标记细菌（FLB）作为猎物类似物和荧光显微镜。细胞特异性的吸收率可以通过在选定的时间程8中量化前列腺食物中标记的猎物颗粒的数量来确定。这种方法有几个优点。追踪器被添加到自然样品与自然捕食者和猎物组合。孵育前有最少的样品操作，添加的FLB示踪剂对样品的改变最小，孵育时间较短，以确保在接近原位条件下获得良好结果。或者，在细菌原虫或浮游动物数量少的环境中（例如近海海洋系统），通过流动细胞测定，可长期（12-24小时）在样品中添加少量FLB的消失率（2%-3%示踪剂）孵化实验。然后，在起点和终点的FLB数量（集成所有细菌的影响）通过流动细胞测定法进行量化（详情请参阅以前的出版物9）。然而，这种参数只代表不能直接归因于任何特定的前列腺动物和浮游动物食草动物群体或物种的总细菌率。
总体而言，准确量化水生环境中的古生物物种或形态特定细菌死亡率可能具有挑战性。一些原生动物是选择性的放牧者，添加的FLB示踪剂的大小和细胞形状可能会扭曲猎物摄入的自然速率10，11。此外，前列腺活性和代谢高度温敏12;因此，需要针对每种样品类型仔细操纵添加的FLB示踪剂量（不仅基于细菌的自然丰度、大小和形态以及细菌的流行类型，还基于温度）。大多数研究侧重于散装牧草放牧活动;然而，特定原物种的细菌通常具有较高的信息价值，并且可能更可取。在这种情况下，需要对样本中存在的原科物种的分类学知识，并了解它们的行为。因此，需要大量的时间和劳动力，才能获得针对特定物种的细菌感染率的健全结果，该比率可归因于特定的前列腺组或物种。
尽管存在这些困难，这种方法仍然是目前可用于在自然环境中评估前列腺细菌的最合适工具。这里介绍了一种在水生微生物生态学研究中使用FLB作为示踪剂的综合性、易于遵循的方法。该方法的所有问题方面都得到了说明，并描述了改进的工作流程，其中有两个来自对比环境的实验以及对比的西利特物种作为示例。
第一个案例研究是在捷克共和国的中生代什莫夫水库的表观环境中进行的，结果表明，与大多数地表淡水体相媲美的食草和细菌丰度（参见第5、7）。第二个案例研究是在水生食肉植物Utricularia反射的陷阱内高度特殊的环境中进行的，这种反射中含有极高数量的两种放牧混合营养性纤酸（四海梅纳眼）和细菌细胞。显示了这两种样本中细胞特异性放牧率和细菌常备库的计算。然后讨论了对结果的一系列生态解释，最后提出了可能的后续研究实例。

<table border="0" cellpadding="0" cellspacing="0" style="width:1612px;" width="1611">
	<tbody>
		<tr height="19">
			<td height="19" style="height:20px;width:360px;">0.2-&#181;m pore-size filters&#160;</td>
			<td style="width:462px;">SPI supplies, https://www.2spi.com/</td>
			<td style="width:137px;">B0225-MB</td>
			<td style="width:654px;">Black, polycarbonate track etch membrane filters, diameter approprite for filtering apparatus used</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:20px;">5-(4,6-dichlorotriazin-2-yl) aminofluorescein (DTAF)</td>
			<td>Any brand</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:20px;">Automatic pipettes with adjustable volumes&#160;</td>
			<td>Any brand, various sizes</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:20px;">Centrifuge</td>
			<td>22 000 x g</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:20px;">Cryovials</td>
			<td>Any brand, 2 mL size</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;">DAPI (4&#180;,6-Diamidino-2&#180;-phenylindole dihydrochloride)</td>
			<td>Any brand&#160;</td>
			<td></td>
			<td>1 mg ml-1</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:20px;">Epiflorescence microscope</td>
			<td>Magnification from 400 x up to 1000 x</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:20px;"></td>
			<td>Filters appropriate for viewing in the DAPI and DTAF range</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:20px;"></td>
			<td>Counting grid in one of the oculars</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:20px;">Filtering apparatus</td>
			<td>Usually with a diameter of 25 mm&#160;</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:20px;">Formaldehyde</td>
			<td>A brand for microscopy</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:20px;">Glutaraldehyde</td>
			<td>A brand for microscopy</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:20px;">Immersion oil for microscopy</td>
			<td>Specific oil with low fluorescence</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="58">
			<td height="58" style="height:58px;">Lugol&#180;s solution</td>
			<td>Any brand or see comment</td>
			<td></td>
			<td style="width:654px;">Make an alkaline Lugol&#39; solution as follows: Solution 1 - dissolve&#160; 10 g of potassium iodide in 20 ml in MQ water, then add 5 g of iodine. Solution 2 - add 5 g of sodium acetate&#160; to 50 ml of MQ water. Add the solution 2 to the solution 1 and thoroughly mix</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:20px;">Methanol stabilized formalin</td>
			<td>Any brand available for microscopy purposes</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:20px;">Microscope slides and cover slips</td>
			<td>Any brand produced for microscopy purposes&#160;</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:23px;">MQ water for diluting samples</td>
			<td style="width:462px;">Any brand 
			&#160;</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Phosphate-buffered saline (PBS; pH = 9)</td>
			<td>Any brand</td>
			<td></td>
			<td>0.05 M Na2HPO4-NaCl solution, adjusted to pH 9</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;">PPi-saline buffer</td>
			<td>Any brand</td>
			<td></td>
			<td style="width:654px;">0.02 M Na4P2O7-NaCl solution. Add 0.53 g Na4P2O7 to 100 ml of MQ water plus 0.85 g NaCl&#160;</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:20px;">Sampling device&#160;</td>
			<td>Appropriate for obtaining representative sample&#160;</td>
			<td></td>
			<td>e.g. Friedinger sampler for lake plankton</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:20px;">Sodium thiosulfate solution</td>
			<td>Any brand</td>
			<td></td>
			<td>3% solution is used in the protocol</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:20px;">Sonicator</td>
			<td>Any brand</td>
			<td></td>
			<td>30 W</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:20px;">Vortex</td>
			<td>Any brand allowing&#160; thorough mixing of the solutes and samples</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:20px;">Water bath</td>
			<td>Any brand allowing temperature to be maintained at 60 &#176;C</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

fluorescently labeled bacteria as a tracer to reveal novel pathways of organic carbon flow in aquatic ecosystems

阐明营养相互作用，如掠夺及其影响，是生态学许多研究者经常的任务。微生物群落的研究有许多局限性，确定捕食者、猎物和捕食率通常很困难。这里介绍的是一种基于添加荧光标记的猎物作为示踪剂的优化方法，它允许可靠地定量水生食肉真核生物的放牧率，并估计营养转移到更高的营养水平。

例如，实验是在切莫夫水库（南波希米亚，CZ），这是一个自然地点，较低的自然原位捕食者和猎物丰度。报告具有代表性的数据为杂食性香菜物种哈尔特里亚格兰尼拉，这是一个丰富和高效的肉食虫颗粒（<2 μm）颗粒10，16，17，18 ， 22.图...

Watch this Scientific Journal Video about Fluorescently Labeled Bacteria as a Tracer to Reveal Novel Pathways of Organic Carbon Flow in Aquatic Ecosystems at JoVE.com

Fluorescently Labeled Bacteria as a Tracer to Reveal Novel Pathways of Organic Carbon Flow in Aquatic Ecosystems

这里介绍的是一种基于单细胞的表氟显微镜技术的协议，用于以高精度和分类分辨率量化水生捕食真核生物的放牧率。

荧光标记细菌作为追踪器揭示水生生态系统中有机碳流动的新途径

Elucidating trophic interactions, such as predation and its effects, is a frequent task for many researchers in ecology. The study of microbial ...

这种方法意义重大，因为它使我们能够以非常高的分辨率可视化和估计从原核生物到微生物食物网中更高营养水平的碳和能量流动。这是目前唯一可用于确定哪些原生物种原位使用细菌的技术，同时在单细胞水平上量化这个过程的速率。由于细菌是唯一重要的微生物，将溶解的有机碳改变为颗粒有机碳，因此，参与者的知识和发生这种物质的比率构成了了解水生生态系统的基础。我们强烈建议研究人员在进行放牧实验之前熟悉他们的研究系统。这涉及到光和荧光的显微镜检查样品，并了解主要分类存在和他们的季节性动态。演示程序将是吉特卡 · 耶兹贝罗夫

Research

JoVE Journal

Environment

Alternative Method of Removing Otoliths from Sturgeon

从鲟鱼去除耳石替代方法

Extracting the otoliths (ear bones) from fish that have very thick skulls can be difficult and very time consuming. The common practice of making a ...

科研

环境科学

Assessment of Labile Organic Carbon in Soil Using Sequential Fumigation Incubation Procedures

活性有机碳评估土壤中连续熏蒸孵化程序

Management practices and environmental changes can alter soil nutrient and carbon cycling. Soil labile organic carbon, a readily decomposable C pool, is ...

Understanding Dissolved Organic Matter Biogeochemistry Through In Situ Nutrient Manipulations in Stream Ecosystems

Understanding Dissolved Organic Matter Biogeochemistry Through In Situ Nutrient Manipulations in Stream Ecosystems

了解溶解有机物生物地球化学通过<em&gt;原位</em&gt;在河流生态系统营养手法

Dissolved organic matter (DOM) is a highly diverse mixture of molecules providing one of the largest sources of energy and nutrients to stream ecosystems. ...

A Flow-through Exposure System for Evaluating Suspended Sediments Effects on Aquatic Life

对水生生命值评价悬浮泥沙影响的流通系统曝光

This paper describes the Fish Larvae and Egg Exposure System (FLEES). The flow-through exposure system is used to investigate the effects of suspended ...

Production and Measurement of Organic Particulate Matter in a Flow Tube Reactor

流管反应器中有机颗粒物的生产与测定

Organic particulate matter (PM) is increasingly recognized as important to the Earth's climate system as well as public health in urban regions, and the ...

Measurement of the Rheology of Crude Oil in Equilibrium with CO2 at Reservoir Conditions

Measurement of the Rheology of Crude Oil in Equilibrium with CO2 at Reservoir Conditions

与CO平衡的原油流变学测量<sub&gt; 2</sub&gt;在水库条件

A rheometer system to measure the rheology of crude oil in equilibrium with carbon dioxide (CO2) at high temperatures and pressures is described. The ...

Ecosystem Fabrication (EcoFAB) Protocols for The Construction of Laboratory Ecosystems Designed to Study Plant-microbe Interactions

Ecosystem Fabrication EcoFAB Protocols for The Construction of Laboratory Ecosystems Designed to Study Plant-microbe Interactions

用于研究植物-微生物相互作用的实验室生态系统制造 (EcoFAB) 协议

Beneficial plant-microbe interactions offer a sustainable biological solution with the potential to boost low-input food and bioenergy production. A ...

Characterization of Aquatic Biofilms with Flow Cytometry

流式细胞仪对水生生物膜的表征

Biofilms are dynamic consortia of microorganism that play a key role in freshwater ecosystems. By changing their community structure, biofilms respond ...

Experimental Protocol for Examining Behavioral Response Profiles in Larval Fish: Application to the Neuro-stimulant Caffeine

检测幼虫行为反应剖面的实验协议: 在神经刺激咖啡因中的应用

Fish models and behaviors are increasingly used in the biomedical sciences; however, fish have long been the subject of ecological, physiological and ...

Use of Principal Components for Scaling Up Topographic Models to Map Soil Redistribution and Soil Organic Carbon

利用主成分扩展地形模型绘制土壤再分配和土壤有机碳

Landscape topography is a critical factor affecting soil formation and plays an important role in determining soil properties on the earth surface, as it ...