نود أن نشكر المؤسسة الكندية للإبداع ، ومعارف كولومبيا البريطانية وصندوق التنمية الوطنية للعلوم والهندسة مجلس البحوث (NSERC) من كندا لدعم الدراسات الجارية على المناطق المنخفضة من الأوكسجين مياه المحيطات والمناطق الساحلية المفتوحة. كان مدعوما من قبل شعبة النهوض بالمرأة من الزمالات NSERC ، Killam ومؤسسة التمويل مركز تولا للتنوع وتطور الميكروبية.

<ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> مجموعة تتكون من أجهزة الترشيح <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> لإعداد جهاز الترشيح ، واستخدام ملاقط لوضع الصف GF / D تصفية وحدة سكنية في prefilter. تشديد فضفاضة السكن باليد. وكقاعدة عامة ، لا الإفراط في تشديد أو الوحدة مرة واحدة في تسرب سوف يبدأ الضخ. </li><li style=";text-align:right;direction:rtl"> استبدال الغطاء الدامجانة زجاجة كبيرة مع غطاء تعقيمها والأنابيب التي توليها إدراج بعناية الأنبوب الداخلي في الدامجانة زجاجة كبيرة دون لمسها. إذا كان ذلك ضروريا ، واستخدام ملاقط لتوجيه الأنبوب في الدامجانة زجاجة كبيرة. </li><li style=";text-align:right;direction:rtl"> تمرير الأنابيب الخارجية من خلال مضخة تمعجية. </li><li style=";text-align:right;direction:rtl"> إرفاق وحدة سكنية prefilter إلى نهاية كل من أنابيب خارجية (أي 2 وحدة في الدامجانة زجاجة كبيرة). إحكام اتصال مع كماشة. </li></ol></li><li style=";text-align:right;direction:rtl"> ترشيح مياه البحر <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> لتبدأ تصفية مياه البحر ، وتشغيل المضخة وضبط سرعة تدفق إلى 1. رايتس ووتش إلى ضمان أن المياه التي يتم ضخها في الاتجاه الصحيح. </li><li style=";text-align:right;direction:rtl"> سماح 500 مل من المياه لتتدفق بحرية من خلال وحدة وprefilter في دورق L 1. </li><li style=";text-align:right;direction:rtl"> إيقاف المضخة ، وإرفاق تصفية Sterivex لتركيب luer الذكور في نهاية خالية من الإعداد prefilter. تشديد بشكل مريح السكن prefilter باليد. </li><li style=";text-align:right;direction:rtl"> مراقبة في السكن prefilter وعلى العلاقة بين السكن وprefilter الأنبوب الذي يؤدي إلى الدامجانة زجاجة كبيرة. إذا تسرب يحدث ، تشغيل المضخة قبالة وتخفيف وإعادة إحكام السكن prefilter تبعا لذلك. تشغيل المضخة مرة أخرى. </li><li style=";text-align:right;direction:rtl"> جمع الراشح في قوارير ل 4. بمجرد أن يتم بالكامل ، والقوارير الفارغة في الدامجانة زجاجة كبيرة نظيفة. لا شك أن نلاحظ حجم مرت كل مرشح. ويمكن جمع مزيد من معالجة الرشاحة ، مثل الترشيح للبحث عن الفيروسات. </li><li style=";text-align:right;direction:rtl"> يستمر الترشيح حتى لا تبقى المياه في carboys. كالعادة مجموعة مرات الترشيح بين 4-5 ح / 20 L الدامجانة زجاجة كبيرة ، ولكن هذا يعتمد بشكل كبير على كمية الكتلة الحيوية داخل الماء. </li><li style=";text-align:right;direction:rtl"> الترشيح مرة واحدة كاملة ، تبديل المضخة وقطع المرشحات Sterivex. </li></ol></li><li style=";text-align:right;direction:rtl"> تخزين الفلاتر <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> لتخزين المرشحات ، وطرد الأولى أي المياه المتبقية مع حقنة مل 30-60. </li><li style=";text-align:right;direction:rtl"> باستخدام ماصة ، إضافة 1.8ml العازلة تحلل إلى تصفية ، وحفظ ~ 200 UL الفضاء في تصفية بالإضافة إلى وقت لاحق من الكواشف. </li><li style=";text-align:right;direction:rtl"> ختم الجزء السفلي والعلوي من تصفية Sterivex مع قطعة صغيرة من Parafilm ، وتسمية المرشحات مع التاريخ وتحديد العينة. </li><li style=";text-align:right;direction:rtl"> تخزين المرشحات في مرحلة ما قبل المسمى 50 مل في أنبوب الصقر -80 درجة مئوية </li><li style=";text-align:right;direction:rtl"> إزالة عوامل التصفية من وحدة سكنية ووضعها المسمى أنابيب فالكون 50 مل تحتوي على 2 مل من تحلل العازلة. تخزين هذه في -80 درجة مئوية. </li></ol></li><li style=";text-align:right;direction:rtl"> تنظيف <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> لتنظيف النهائي ، وضع الأنابيب التي كان داخل الدامجانة زجاجة كبيرة في قارورة تحتوي على حمض الهيدروكلوريك 0.1 M </li><li style=";text-align:right;direction:rtl"> توجيه أنابيب التي تؤدي إلى القارورة 4L في الدامجانة زجاجة كبيرة الأصلي. </li><li style=";text-align:right;direction:rtl"> التبديل على المضخة وتشغيلها في 3 ، وجمع من خلال تدفق تشغيل في الدامجانة زجاجة كبيرة الأصلي. </li><li style=";text-align:right;direction:rtl"> أخيرا ، شطف الأنابيب بالماء تعقيمها. </li></ol></li></ol> ممثل النتائج : النتيجة النهائية يتكون من المرشحات التي تحتوي كل منهما Sterivix الكتلة الحيوية الميكروبية من مياه البحر حوالي 10 لتر في نطاق وحجم 0.22μm 2.7μm. يتم تخزين هذه العازلة في تحلل وعلى استعداد لاستخراج الحمض النووي. بالإضافة إلى ذلك ، هذا الإجراء تجمع وتركز الكتلة أكبر من 2.7 ميكرون ، على prefilters GF / د. كما يتم تخزين هذه العازلة في تحلل وعلى استعداد لاستخراج الحمض النووي. إذا اتخذت خطوات معالجة إضافية ، ويمكن أن تتركز على 0.22 ميكرومتر التدفق من خلال وصولا الى جمع الكسر الفيروسية كذلك.

The authors have nothing to disclose.

ومن الضروري أن يمسح أسفل المقاعد ومضخات بمنشفة مبللة بعد الاستخدام لإزالة أي آثار متبقية من المياه المالحة التي من شأنها أن خلاف ذلك تآكل المعدات. على الرغم من أن هذا الإجراء هو بسيط ، يمكن أن تكون واسعة شرط الوقت اعتمادا على تركيز الكتلة الحيوية أو الحطام في العينة ا...

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		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
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<tr>
<td>Peristaltic pump</td>
<td>&nbsp;</td>
<td>Masterflex (Cole Palmer)</td>
<td>77913-20, 77200-62, 77200-04</td>
<td>&nbsp;</td>
<tr>
<td>Tygon LFL tubing</td>
<td>&nbsp;</td>
<td>Masterflex (Cole Palmer)</td>
<td>06429-24</td>
<td>For filtration apparatus</td>
</tr>
<tr>
<td>Hose clamps</td>
<td>&nbsp;</td>
<td>Cole Palmer</td>
<td>0683204</td>
<td>For filtration apparatus</td>
</tr>
<tr>
<td>1/4&#x201D; x 3/16&#x201D; pipe adaptors</td>
<td>&nbsp;</td>
<td>Cole Palmer</td>
<td>31702-20</td>
<td>For filtration apparatus</td>
</tr>
<tr>
<td>Polypropylene prefilter housing</td>
<td>&nbsp;</td>
<td>ADVANTEC</td>
<td>501200</td>
<td>For filtration apparatus</td>
</tr>
<tr>
<td>Metal luer fitting (Hose end to Male luer lock)</td>
<td>&nbsp;</td>
<td>Cole Palmer</td>
<td>31507-27</td>
<td>For filtration apparatus</td>
</tr>
<tr>
<td>2&#x201C; Magnets</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>For filtration apparatus</td>
<td>&nbsp;</td>
<tr>
<td>3 port carboy caps</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>For filtration apparatus</td>
</tr>
<tr>
<td>GV 0.22 &mu;m STERIVIX filters</td>
<td>&nbsp;</td>
<td>Millipore</td>
<td>SVGV01R5</td>
<td>&nbsp;</td>
<tr>
<td>47 mm diameter 2.7 &mu;m GF/D filters</td>
<td>&nbsp;</td>
<td>Whatman</td>
<td>1823047</td>
<td>&nbsp;</td>
<tr>
<td>Lysis buffer</td>
<td> Reagent</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>0.75 M sucrose, 40 mM EDTA, 50 mM Tris (pH 8.3)</td>
</tr>
<tr>
<td>0.1 % HCl</td>
<td>Reagent</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>For post-filtration rinse</td>
</tr>
<tr>
<td>Autoclaved water</td>
<td>Reagent</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>For post-filtration rinse</td>
</tr>		</tbody>
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large volume (20l+) filtration of coastal seawater samples

يبدأ سير العمل في جمع المياه البحرية الساحلية للمجتمع الميكروبية المصب ، ويحلل الغاز المغذيات والتتبع. لهذا الأسلوب ، وقد تم جمع عينات من سطح التشغيل سفينتى جون ستريكلاند في مدخل Saanich. هذا الكتاب وثائق الفيديو الكبيرة (L ≥ 20) ترشيح الكتلة الحيوية الميكروبية ، وتتراوح ما بين 0.22μm 2.7μm في القطر ، من عمود الماء. يمكن تصفيتها عينتين 20L في وقت واحد باستخدام مضخة وحدة واحدة مزودة أربعة رؤساء بالتناوب. ويتم الترشيح في الميدان في رحلات طويلة ، أو فور مقابل رحلات يومية. فمن المهم لتسجيل كمية المياه التي تمر عبر كل وحدة تصفية sterivex. لمنع تشكيل بيوفيلم رحلات بين أخذ العينات ، يجب شطف جميع المعدات الترشيح مع حمض الهيدروكلوريك المخفف والمياه وتعقيمها منزوع الأيونات بعد الاستعمال مباشرة. وسوف يستغرق هذا الإجراء ما يقرب من 5 ساعات بالإضافة إلى ساعة إضافية للتنظيف.

Watch this Scientific Journal Video about Large Volume 20L+ Filtration of Coastal Seawater Samples at JoVE.com

Large Volume 20L+ Filtration of Coastal Seawater Samples

هذا الكتاب وثائق الفيديو الكبيرة (L ≥ 20) ترشيح الكتلة الحيوية الميكروبية ، وتتراوح ما بين 0.22μm 2.7μm في القطر ، من عمود الماء.

كبيرة الحجم (20L +) الترشيح لعينة من ماء البحر الساحلية

The workflow begins with the collection of coastal marine waters for downstream microbial community, nutrient and trace gas analyses. For this method, ...

large-volume-20l-filtration-of-coastal-seawater-samples

Research

JoVE Journal

Biology

Large Volume (20L+) Filtration of Coastal Seawater Samples

11.7K Views.  University of British Columbia - UBC. هذا الكتاب وثائق الفيديو الكبيرة (L ≥ 20) ترشيح الكتلة الحيوية الميكروبية ، وتتراوح ما بين 0.22μm 2.7μm في القطر ، من عمود الماء.

Video: Large Volume 20L+ Filtration of Coastal Seawater Samples

EPA Method 1615. Measurement of Enterovirus and Norovirus Occurrence in Water by Culture and RT-qPCR. I. Collection of Virus Samples

EPA Method 1615 was developed with a goal of providing a standard method for measuring enteroviruses and noroviruses in environmental and drinking waters. The standardized sampling component of the method concentrates viruses that may be present in water by passage of a minimum specified volume of water through an electropositive cartridge filter. The minimum specified volumes for surface and finished/ground water are 300 L and 1,500 L, respectively. A major method limitation is the tendency for the filters to clog before meeting the sample volume requirement. Studies using two different, but equivalent, cartridge filter options showed that filter clogging was a problem with 10% of the samples with one of the filter types compared to 6% with the other filter type. Clogging tends to increase with turbidity, but cannot be predicted based on turbidity measurements only. From a cost standpoint one of the filter options is preferable over the other, but the water quality and experience with the water system to be sampled should be taken into consideration in making filter selections.

EPA Method 1615 uses an electropositive filter to concentrate enteroviruses and noroviruses in environmental and drinking waters. This manuscript describes the procedure for collecting samples for Method 1615 analyses.

EPA الطريقة 1615. قياس الفيروسة المعوية ونوروفيروس حدوثها في المياه عن طريق الثقافة وRT-QPCR. I. جمع عينات الفيروسات

EPA Method 1615 was developed with a goal of providing a standard method for measuring enteroviruses and noroviruses in environmental and drinking waters. ...

Environment

Estimating Virus Production Rates in Aquatic Systems

Viruses are pervasive components of marine and freshwater systems, and are known to be significant agents of microbial mortality. Developing quantitative estimates of this process is critical as we can then develop better models of microbial community structure and function as well as advance our understanding of how viruses work to alter aquatic biogeochemical cycles. The virus reduction technique allows researchers to estimate the rate at which virus particles are released from the endemic microbial community. In brief, the abundance of free (extracellular) viruses is reduced in a sample while the microbial community is maintained at near ambient concentration. The microbial community is then incubated in the absence of free viruses and the rate at which viruses reoccur in the sample (through the lysis of already infected members of the community) can be quantified by epifluorescence microscopy or, in the case of specific viruses, quantitative PCR. These rates can then be used to estimate the rate of microbial mortality due to virus-mediated cell lysis.

The turnover rate of viruses in marine and freshwater systems can be estimated by a reduction and reoccurrence technique. The data allow researchers to infer rates of virus-mediated microbial mortality in aquatic systems.

تقدير معدلات الإنتاج الفيروسات في النظم المائية

Viruses are pervasive components of marine and freshwater systems, and are known to be significant agents of microbial mortality. Developing quantitative ...

Immunology and Infection

Unraveling the Unseen Players in the Ocean - A Field Guide to Water Chemistry and Marine Microbiology

Here we introduce a series of thoroughly tested and well standardized research protocols adapted for use in remote marine environments. The sampling protocols include the assessment of resources available to the microbial community (dissolved organic carbon, particulate organic matter, inorganic nutrients), and a comprehensive description of the viral and bacterial communities (via direct viral and microbial counts, enumeration of autofluorescent microbes, and construction of viral and microbial metagenomes). We use a combination of methods, which represent a dispersed field of scientific disciplines comprising already established protocols and some of the most recent techniques developed. Especially metagenomic sequencing techniques used for viral and bacterial community characterization, have been established only in recent years, and are thus still subjected to constant improvement. This has led to a variety of sampling and sample processing procedures currently in use. The set of methods presented here provides an up to date approach to collect and process environmental samples. Parameters addressed with these protocols yield the minimum on information essential to characterize and understand the underlying mechanisms of viral and microbial community dynamics. It gives easy to follow guidelines to conduct comprehensive surveys and discusses critical steps and potential caveats pertinent to each technique.

Here, we present a comprehensive protocol to assess the organic and inorganic nutrient availability and the abundance and structure of microbial and viral communities in remote marine environments.

كشف اللاعبين غير مرئي في المحيط - دليل ميداني للكيمياء المياه وعلم الأحياء المجهرية البحرية

Here we introduce a series of thoroughly tested and well standardized research protocols adapted for use in remote marine environments. The sampling ...

VacuSIP, an Improved InEx Method for In Situ Measurement of Particulate and Dissolved Compounds Processed by Active Suspension Feeders

Benthic suspension feeders play essential roles in the functioning of marine ecosystems. By filtering large volumes of water, removing plankton and detritus, and excreting particulate and dissolved compounds, they serve as important agents for benthic-pelagic coupling. Accurately measuring the compounds removed and excreted by suspension feeders (such as sponges, ascidians, polychaetes, bivalves) is crucial for the study of their physiology, metabolism, and feeding ecology, and is fundamental to determine the ecological relevance of the nutrient fluxes mediated by these organisms. However, the assessment of the rate by which suspension feeders process particulate and dissolved compounds in nature is restricted by the limitations of the currently available methodologies. Our goal was to develop a simple, reliable, and non-intrusive method that would allow clean and controlled water sampling from a specific point, such as the excurrent aperture of benthic suspension feeders, in situ. Our method allows simultaneous sampling of inhaled and exhaled water of the studied organism by using minute tubes installed on a custom-built manipulator device and carefully positioned inside the exhalant orifice of the sampled organism. Piercing a septum on the collecting vessel with a syringe needle attached to the distal end of each tube allows the external pressure to slowly force the sampled water into the vessel through the sampling tube. The slow and controlled sampling rate allows integrating the inherent patchiness in the water while ensuring contamination free sampling. We provide recommendations for the most suitable filtering devices, collection vessel, and storing procedures for the analyses of different particulate and dissolved compounds. The VacuSIP system offers a reliable method for the quantification of undisturbed suspension feeder metabolism in natural conditions that is cheap and easy to learn and apply to assess the physiology and functional role of filter feeders in different ecosystems.

VacuSIP, an Improved InEx Method for In Situ Measurement of Particulate and Dissolved Compounds Processed by Active Suspension Feeders

We introduce the VacuSIP, a simple, non-intrusive, and reliable method for clean and accurate point sampling of water. The system was developed and evaluated for the simultaneous collection of the water inhaled and exhaled by benthic suspension feeders in situ, to cleanly measure removal and excretion of particulate and dissolved compounds.

VacuSIP، وتحسين أسلوب INEX ل<em&gt; في الموقع</em&gt; قياس الجسيمات والمذاب المركبات التي تتم معالجتها بواسطة مغذيات تعليق النشطة

Benthic suspension feeders play essential roles in the functioning of marine ecosystems. By filtering large volumes of water, removing plankton and ...

Use of a Filter Cartridge for Filtration of Water Samples and Extraction of Environmental DNA

Recent studies demonstrated the use of environmental DNA (eDNA) from fishes to be appropriate as a non-invasive monitoring tool. Most of these studies employed disk fiber filters to collect eDNA from water samples, although a number of microbial studies in aquatic environments have employed filter cartridges, because the cartridge has the advantage of accommodating large water volumes and of overall ease of use. Here we provide a protocol for filtration of water samples using the filter cartridge and extraction of eDNA from the filter without having to cut open the housing. The main portions of this protocol consists of 1) filtration of water samples (water volumes &#8804;4 L or &gt;4 L); (2) extraction of DNA on the filter using a roller shaker placed in a preheated incubator; and (3) purification of DNA using a commercial kit. With the use of this and previously-used protocols, we perform metabarcoding analysis of eDNA taken from a huge aquarium tank (7,500 m3) with known species composition, and show the number of detected species per library from the two protocols as the representative results. This protocol has been developed for metabarcoding eDNA from fishes, but is also applicable to eDNA from other organisms.

We describe a protocol for filtration of water samples with a filter cartridge and extraction of environmental DNA (eDNA) without having to cut open the housing to remove the filter. This protocol is developed for metabarcoding eDNA from fishes, but is also applicable to eDNA from other organisms.

استخدام خرطوشة مرشح للترشيح المياه العينات واستخلاص الحمض النووي البيئي

Recent studies demonstrated the use of environmental DNA (eDNA) from fishes to be appropriate as a non-invasive monitoring tool. Most of these studies ...

An Ultra-clean Multilayer Apparatus for Collecting Size Fractionated Marine Plankton and Suspended Particles

The distributions of many trace elements in the ocean are strongly associated with the growth, death, and re-mineralization of marine plankton and those of suspended/sinking particles. Here, we present an all plastic (Polypropylene and Polycarbonate), multi-layer filtration system for collection of suspended particulate matter (SPM) at sea. This ultra-clean sampling device has been designed and developed specifically for trace element studies. Meticulous selection of all non-metallic materials and utilization of an in-line flow-through procedure minimizes any possible metal contamination during sampling. This system has been successfully tested and tweaked for determining trace metals (e.g., Fe, Al, Mn, Cd, Cu, Ni) on particles of varying size in coastal and open ocean waters. Results from the South China Sea at the South East Asia Time-Series (SEATS) station indicate that diurnal variations and spatial distribution of plankton in the euphotic zone can be easily resolved and recognized. Chemical analysis of size-fractionated particles in surface waters of the Taiwan Strait suggests that the larger particles (&#62;153 &#181;m) were mostly biologically derived, while the smaller particles (10 - 63 &#181;m) were mostly composed of inorganic matter. Apart from Cd, the concentrations of metals (Fe, Al, Mn, Cu, Ni) decreased with increasing size.

Plankton and suspended particles play a major role in the biogeochemical cycles in the ocean. Here, we provide an ultra-clean, low stress method for the collection of various sizes of particles and plankton at sea with the capability of handling large volumes of seawater.

جهاز متعدد الطبقات نظيفة جداً لجمع العوالق البحرية الحجم مجزأ والجسيمات المعلقة

The distributions of many trace elements in the ocean are strongly associated with the growth, death, and re-mineralization of marine plankton and those ...

Sampling, Sorting, and Characterizing Microplastics in Aquatic Environments with High Suspended Sediment Loads and Large Floating Debris

The ubiquitous presence of plastic debris in the ocean is widely recognized by the public, scientific communities, and government agencies. However, only recently have microplastics in freshwater systems, such as rivers and lakes, been quantified. Microplastic sampling at the surface usually consists of deploying drift nets behind either a stationary or moving boat, which limits the sampling to environments with low levels of suspended sediments and floating or submerged debris. Previous studies that employed drift nets to collect microplastic debris typically used nets with &#8805;300 &#181;m mesh size, allowing plastic debris (particles and fibers) below this size to pass through the net and elude quantification. The protocol detailed here enables: 1) sample collection in environments with high suspended loads and floating or submerged debris and 2) the capture and quantification of microplastic particles and fibers &lt;300 &#181;m. Water samples were collected using a peristaltic pump in low-density polyethylene (PE) containers to be stored before filtering and analysis in the lab. Filtration was done with a custom-made microplastic filtration device containing detachable union joints that housed nylon mesh sieves and mixed cellulose ester membrane filters. Mesh sieves and membrane filters were examined with a stereomicroscope to quantify and separate microplastic particulates and fibers. These materials were then examined using a micro-attenuated total reflectance Fourier transform infrared spectrometer (micro ATR-FTIR) to determine microplastic polymer type. Recovery was measured by spiking samples using blue PE particulates and green nylon fibers; percent recovery was determined to be 100% for particulates and 92% for fibers. This protocol will guide similar studies on microplastics in high velocity rivers with high concentrations of sediment. With simple modifications to the peristaltic pump and filtration device, users can collect and analyze various sample volumes and particulate sizes.

Most microplastic research to date has occurred in marine systems where suspended solid levels are relatively low. Focus is now shifting to freshwater systems, which may feature high sediment loads and floating debris. This protocol addresses collecting and analyzing microplastic samples from aquatic environments that contain high suspended solid loads.

أخذ العينات، والفرز، وتميز ميكروبلاستيكس في البيئات المائية مع أحمال الرواسب المعلقة عالية وكبيرة من الحطام العائم

The ubiquitous presence of plastic debris in the ocean is widely recognized by the public, scientific communities, and government agencies. However, only ...

Combined Size and Density Fractionation of Soils for Investigations of Organo-Mineral Interactions

Combined size and density fractionation (CSDF) is a method used to physically separate soil into fractions differing in particle size and mineralogy. CSDF relies on sequential density separation and sedimentation steps to isolate (1) the free light fraction (uncomplexed organic matter), (2) the occluded light fraction (uncomplexed organic matter trapped in soil aggregates) and (3) a variable number of heavy fractions (soil minerals and their associated organic matter) differing in composition. Provided that the parameters of the CSDF (dispersion energy, density cut-offs, sedimentation time) are properly selected, the method yields heavy fractions of relatively homogeneous mineral composition. Each of these fractions is expected to have a different complexing ability towards organic matter, rendering this a useful method to isolate and study the nature of organo-mineral interactions. Combining density and particle size separation brings an improved resolution compared to simple size or density fractionation methods, allowing the separation of heavy components according to both mineralogy and size (related to surface area) criteria. As is the case for all physical fractionation methods, it may be considered as less disruptive or aggressive than chemically-based extraction methods. However, CSDF is a time-consuming method and furthermore, the quantity of material obtained in some fractions can be limiting for subsequent analysis. Following CSDF, the fractions may be analyzed for mineralogical composition, soil organic carbon concentration and organic matter chemistry. The method provides quantitative information about organic carbon distribution within a soil sample and brings light to the sorptive capacity of the different, naturally-occurring mineral phases, thus providing mechanistic information about the preferential nature of organo-mineral interactions in soils (i.e., which minerals, what type of organic matter).

Combined size and density fractionation (CSDF) is a method to physically separate soil into fractions differing in texture (particle size) and mineralogy (density). The purpose is to isolate fractions with different reactivities towards soil organic matter (SOM), in order to better understand organo-mineral interactions and SOM dynamics.

حجم المدمجة ووجود كثافة التربة للتحقيقات المتعلقة بالتفاعلات المعدنية Organo

Combined size and density fractionation (CSDF) is a method used to physically separate soil into fractions differing in particle size and mineralogy. CSDF ...

Seawater Sampling and Collection

This video documents methods for collecting coastal marine water samples and processing them for various downstream applications including biomass concentration, nucleic acid purification, cell abundance, nutrient and trace gas analyses. For today's demonstration samples were collected from the deck of the HMS John Strickland operating in Saanich Inlet. An A-frame derrick, with a multi-purpose winch and cable system, is used in combination with Niskin or Go-Flo water sampling bottles. Conductivity, Temperature, and Depth (CTD) sensors are also used to sample the underlying water mass. To minimize outgassing, trace gas samples are collected first.  Then, nutrients, water chemistry, and cell counts are determined. Finally, waters are collected for biomass filtration. The set-up and collection time for a single cast is ~1.5 hours at a maximum depth of 215 meters. Therefore, a total of 6 hours is generally needed to complete the collection series described here.

This video documents methods for collecting coastal marine water samples and processing them for various downstream applications including biomass concentration, nucleic acid purification, cell abundance, nutrient and trace gas analyses.

أخذ عينات مياه البحر وكوكتيل

This video documents methods for collecting coastal marine water samples and processing them for various downstream applications including biomass ...

Small Volume (1-3L) Filtration of Coastal Seawater Samples

The workflow begins with the collection of coastal marine waters for downstream microbial community, nutrient and trace gas analyses. For today s demonstration samples were collected from the deck of the HMS John Strickland operating in Saanich Inlet. This video documents small volume (~1 L) filtration of microbial biomass from the water column. The protocol is an extension of the large volume sampling protocol described earlier, with one major difference: here, there is no pre-filtration step, so all size classes of biomass are collected down to the 0.22 &mu;m filter cut-off. Samples collected this way are ideal for nucleic acid analysis. The set-up, filtration, and clean-up steps each take about 20-30 minutes. If using two peristaltic pumps simultaneously, up to 8 samples may be filtered at the same time. To prevent biofilm formation between sampling trips, all filtration equipment must be rinsed with dilute HCl and deionized water and autoclaved immediately after use.

Small Volume 1-3L Filtration of Coastal Seawater Samples

This video documents small volume (~1 L) filtration of microbial biomass from the water column.

كبيرة الحجم (20L +) الترشيح لعينة من ماء البحر الساحلية

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