نشكر سكوير Valleevue وادي ريدج مزارع جامعة كيس ويسترن ريزيرف، بما في ذلك A. Locci، C. بوند، وA. Alldridge، لمساعدة إنشاء حديقة مشتركة. قدمت J. خطاف، L. هوفمان، L. غونزاليس، SC ليهي، B. Ochocki، A. Ubiles، C. يو، اكس تشاو، وNM زيمرمان المساعدة المجال. وتم تمويل AJB وJHB من أموال بدء التشغيل من CWRU لJHBGAD كان مدعوما من البرامج الصيفية في منحة الجامعية بحوث من CWRU بتمويل من معهد هوارد هيوز الطبي. وأيد هذا العمل أيضا من خلال تمويل المؤسسة الوطنية للعلوم إلى JHB (DEB 1250170).

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والكتاب ليس لديهم ما يكشف.

من المحتمل جدا في المجتمعات الطبيعية التجانس التربة الناجم عن المصنع لمصانع لها آثار كبيرة، وغالبا ما أنواع محددة على بيئة التربة والنباتات اللاحقة التي تواجه تلك التربة (مثل بيترمان وآخرون 13). ومع ذلك، فإن فهمنا لدور هذا النوع من عدم التجانس في المجت...

أحد الأهداف الأساسية للمجتمع والبيئة هو شرح والتنبؤ العمليات التي تحكم التجمع المجتمع. ومع ذلك، المجتمعات النباتية هي في كثير من الأحيان أكثر تنوعا مما كان متوقعا من قبل نظرية التعايش 1، وعلماء البيئة الترميم بحاجة إلى فهم آليات التعايش لاستعادة المجتمعات المحلية المتنوعة 2 بنجاح. عدم التجانس البيئي هو آلية هامة من الناحية النظرية التي يمكن أن تساعد في تفسير مستويات عالية من التنوع المجتمعي، ولكن التلاعب التجريبية من عدم التجانس نادرة 3 والتركيز على التجانس غير الحيوية (مثل استعرضت في Lundholm 4). النظرية التي تتضمن عدم التجانس يفترض عادة أن عدم التجانس هو خارجي للمجتمع تجميع. ويخضع عدم التجانس خارجي بفعل عوامل مثل تصنيف المناظر الطبيعية، التي هي مستقلة عن تكوين المجتمع. عدم التجانس خارجي يمكن أن يؤدي إلى التعايش من خلال كوة التقسيم ([رفي]الأربعاء في ملبورن وآخرون. 3، على سبيل المثال Pacala وتيلمان 5 و 6 Chesson). ومع ذلك، فإن الكثير من عدم التجانس البيئية ذات الصلة المجتمعات النباتية قد يكون الجوهرية للمجتمع، وتطوير كما يجمع المجتمع وتبعا لهوية الأنواع في المجتمع. عدم تجانس جوهري يمكن أن تنجم عن الاصداء الحيوية، والتي يمكن أن تؤدي إلى التعايش من خلال السلبية التردد الاعتماد (على سبيل المثال بيفير آخرون. 7). هنا، نحن تصف طريقة جديدة لمعالجة عدم تجانس التربة الناجم عن المصنع، وهو نوع من عدم التجانس التربة التي هي جوهرية للمجتمع وتنشأ من الاصداء التربة النباتية. الاصداء التربة النباتية (PSF) تحدث عندما تؤثر النباتات بنية التربة والكيمياء، أو الكائنات الحية بطريقة تؤثر على أداء المحطة اللاحقة في هذا التربة، وقوات الأمن الفلسطينية أن يكون لها آثار كبيرة على متوسط ​​أداء المصنع في المجتمعات النباتية المحلية 8. والدراسات من قوات الأمن الفلسطينية التي تم جمعها عادة إما التربة من الحقل أو التربة مكيفة تجريبيا، ثم سألت عن كيفية أداء النباتات في التربة مناوع النسبية لتعقيم التربة مغاير نوعي أو 9. إذا النباتات أداء أفضل في مناوع النسبية التربة التربة إلى مرجع، ثم PSF إيجابية، في حين إذا النباتات أداء أفضل في التربة المرجعية، PSF سلبية. PSF السلبية المتبادلة يمكن أن يؤدي إلى التعايش التي تعتمد على تردد بين الأنواع 7. في حين أن الآثار يعني من قوات الأمن الفلسطينية هي تتميز كذلك-8، وآثار التباين المكاني في قوات الأمن الفلسطينية ولا يزال الغموض يكتنف 10. لأن قوات الأمن الفلسطينية تحدث على نطاق والنباتات الفردية (7) ولأن النباتات عادة ما تكون موزعة nonrandomly في المكان والزمان، قوات الأمن الفلسطينية من المرجح أن تؤدي إلى عدم تجانس التربة، والتي نسميها عدم تجانس التربة الناجم عن المصنع. على عكس العديد من الأشكال الأخرى من عدم التجانس (مثل طوبولوجيا المناظر الطبيعية)، وهذا heterogeneity غير الجوهرية للمجتمع تجميع وبالتالي قد تؤثر التجمع المجتمع بشكل مختلف عن أشكال أكثر خارجي من عدم التجانس. من أجل فهم تأثير هذا الشكل من عدم التجانس في أداء المصنع والتعايش، ونحن بحاجة الى طرق التجريبية التي تعالج عدم تجانس التربة الناجم عن المصنع. هنا، علينا أن نظهر مثل هذا الأسلوب، والذي يستخدم من قبل اثنين من التربة مكيفة الأنواع لإنشاء المعاملة غير متجانسة مع بقع منفصلة عن اثنين من أصول التربة والعلاج متجانسة، والذي هو خليط من أصول التربة اثنين. هذا خلط التربة يمكن أن تمثل ما لا يقل عن اثنين من سيناريوهات محتملة في هذا المجال: (1) اضطراب (مثل القوارض والزراعة) التي تمزج التربة من أصول مختلفة أو (2) النباتات من نوعين المتزايد على مقربة، مثل أن المناطق نفوذهم الجذر تختلط والتجانس. نقدم اثنين سبيل المثال التجارب التي تستخدم التجانس التربة الناجم عن مصنع للإجابة على الأسئلة الأساسية في LEVE مختلفةليرة سورية من منظمة بيئية: (1) هل يستجيب السكان لزراعة النباتات التي يسببها عدم تجانس التربة؟ و (2) هل تستجيب النباتات الفردية لعدم تجانس التربة الناجمة عن النباتات؟ نحن تصف تجربة حقلية باستخدام 6 بقع التربة لمعالجة مسألة الأولى وتجربة الدفيئة باستخدام 2 بقع التربة لمعالجة مسألة الثانية. قياس كل من السكان واستجابات النبات الفردية لعدم تجانس التربة أمر ضروري لفهم كيفية تجميع التجانس التأثيرات المجتمع.

<table border="0" cellpadding="0" cellspacing="0" width="1119">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Shovel(s)</td>
			<td style="width:136px;">Any</td>
			<td style="width:71px;">NA</td>
			<td style="width:696px;">It is helpful to have at least two shovels, one for each species of soil origin.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Trowel(s)</td>
			<td style="width:136px;">Any</td>
			<td style="width:71px;">NA</td>
			<td style="width:696px;">It is necessary to have at least two trowels of identical size, one for each species of soil origin.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Gloves</td>
			<td style="width:136px;">Any</td>
			<td style="width:71px;">NA</td>
			<td style="width:696px;">Gardening gloves can be used.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Diluted bleach</td>
			<td style="width:136px;">Any</td>
			<td style="width:71px;">NA</td>
			<td style="width:696px;">We use an ~1:10 concentration of household bleach (containing 5-10% NaClO) to water to sterilize all equipment between soil collections.</td>
		</tr>
		<tr height="50">
			<td height="50" style="height:50px;width:216px;">Plastic grid(s)</td>
			<td style="width:136px;">Any</td>
			<td style="width:71px;">NA</td>
			<td style="width:696px;">CUSTOM. We used plastic sheeting from the construction of greenhouse walls to create the grid used in the field experiment. However any stiff plastic that can be manipulated can be used. It is helpful to have three grids to produce reciprocal heterogeneous treatments and a homogeneous treatment without needing to sterilize between each experimental unit.</td>
		</tr>
		<tr height="47">
			<td height="47" style="height:47px;width:216px;">Plastic dividers</td>
			<td style="width:136px;">Any</td>
			<td style="width:71px;">NA</td>
			<td style="width:696px;">CUSTOM. We used stiff sheets of plastic, cut to fit the pot minimum width, such that they can slide down to the bottom of the pot for the greenhouse experiment. It is helpful to have at least two dividers, one for heterogeneous and one for homogeneous treatments, if investigators want to randomize the order in which experimental units within a block are filled without needing to sterilize the divider in between each experimental unit.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Buckets or wheelbarrows</td>
			<td style="width:136px;">Any</td>
			<td style="width:71px;">NA</td>
			<td style="width:696px;">Any container for transporting soils.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Seeds</td>
			<td style="width:136px;">Any</td>
			<td style="width:71px;">NA</td>
			<td style="width:696px;">We collect seeds in the field by hand. Seeds can also be ordered from horticultural suppliers, if appropriate.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Plastic toothpicks</td>
			<td style="width:136px;">Soodhalter Plastics, Inc.</td>
			<td>805KP</td>
			<td style="width:696px;">We plant individual seeds glued on toothpick in the field experiment, to facilitate monitoring germination and survival of individuals.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Water soluble glue</td>
			<td style="width:136px;">Elmer&#39;s</td>
			<td style="width:71px;">Elmer&#39;s Glue-all</td>
			<td style="width:696px;">Any water soluble glue can be used to adhere seeds to plastic toothpicks.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Pots</td>
			<td style="width:136px;">Any</td>
			<td style="width:71px;">NA</td>
			<td style="width:696px;">Pot size will depend on experimental plants used and number of soil patches desired (e.g. 2 or 6).</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Sand</td>
			<td style="width:136px;">Any</td>
			<td style="width:71px;">NA</td>
			<td style="width:696px;">Coarse sand may be mixed with field soils to improve drainage in pots.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Lab tape&#160;</td>
			<td style="width:136px;">Any</td>
			<td style="width:71px;">NA</td>
			<td style="width:696px;">Tape may be used to label equipment used in handling soils with the species of origin.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Pin flags</td>
			<td style="width:136px;">Any</td>
			<td style="width:71px;">NA</td>
			<td style="width:696px;">Flags can be used to identify individuals in the field, prior to soil collection.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Landscape fabric</td>
			<td style="width:136px;">Any</td>
			<td style="width:71px;">NA</td>
			<td style="width:696px;">Landscape fabric can be used in the field to minimize the growth of plants outside experimental plots.</td>
		</tr>
	</tbody>
</table>

experimental protocol for manipulating plant-induced soil heterogeneity

وكثيرا ما يعامل نظرية التعايش التجانس البيئي باعتبارها مستقلة عن تكوين المجتمع، ولكن الاصداء الحيوية مثل الاصداء التربة النباتية (قوات الأمن الفلسطينية) يكون لها آثار كبيرة على أداء المصنع، وخلق التجانس البيئية التي تعتمد على تكوين المجتمع. فهم أهمية PSF لتجميع المجتمع النبات يتطلب فهم دور من عدم التجانس في قوات الأمن الفلسطينية، بالإضافة إلى الآثار يعني PSF. هنا، نحن تصف بروتوكول لمعالجة عدم تجانس التربة الناجم عن المصنع. وتعرض اثنين من التجارب سبيل المثال: (1) تجربة ميدانية مع شبكة 6 رقعة من التربة لقياس الاستجابات الكثافة النباتية و(2) تجربة مع التربة المسببة للاحتباس الحراري 2 التصحيح لقياس استجابات النبات الفردية. التربة التي يمكن جمعها من منطقة النفوذ الجذر (التربة من ريزوسفير والمتاخمة مباشرة إلى منطقة الجذور) من النباتات في الحقل من الأنواع النباتية مناوع ومغاير نوعي. تكرار جمعوتستخدم أيونات لتجنب pseudoreplicating عينات التربة. ثم توضع هذه التربة في بقع منفصلة للعلاجات غير متجانسة أو مختلطة لعلاج المتجانس. ينبغي توخي الحذر لضمان أن العلاجات غير متجانسة والمتجانس تواجه نفس الدرجة من اضطراب التربة. ويمكن بعد ذلك أن توضع النباتات في هذه العلاجات التربة لتحديد تأثير عدم التجانس التربة الناجم عن المصنع على أداء المصنع. علينا أن نبرهن على النتائج الناجمة عن عدم التجانس في مصنع نتائج مختلفة مما كان متوقعا من قبل نماذج التعايش التقليدية، ربما بسبب الطبيعة الديناميكية لهذه المرتدة. هناك حاجة إلى نظرية أن يتضمن التجانس البيئي يتأثر المجتمع تجميع والعمل التجريبي إضافية لتحديد متى التجانس الجوهرية للمجتمع تجميع سوف يؤدي إلى نتائج تجميع مختلفة مقارنة مع عدم التجانس خارجي لتكوين المجتمع.

استجاب الأنواع التي يسببها زرع لعدم التجانس التربة بطرق متنوعة في كل من السكان والمستوى الفردي (أرقام 3 و 4)، مع آثار لتجميع المجتمع. لتحديد ما إذا كان السكان النبات الرد على تجانس التربة الناجم عن المصنع، أنشئ التجربة الميدانية كما هو الحال في البرو...

Watch this Scientific Journal Video about Experimental Protocol for Manipulating Plant-induced Soil Heterogeneity at JoVE.com

بروتوكول تجريبي لمعالجة عدم تجانس التربة الناجم عن النبات | البيئة | فيديو

Experimental Protocol for Manipulating Plant-induced Soil Heterogeneity

فهم دور التجانس البيئي في التعايش الأنواع ركزت عادة على أنواع من عدم التجانس التي هي خارجي لتكوين الأنواع في المجتمع. نحن نقدم طرق تفصيلية جديدة لخلق تجانس التربة باستخدام العلاجات التربة الموضوع إلى التربة النباتية تكييف ردود الفعل، أو عدم تجانس جوهري لتكوين المجتمع.

بروتوكول التجريبية لالناجم عن النبات والتلاعب التجانس التربة

Coexistence theory has often treated environmental heterogeneity as being independent of the community composition; however biotic feedbacks such as ...

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18.6K Views.  Case Western Reserve University.  فهم دور التجانس البيئي في التعايش الأنواع ركزت عادة على أنواع من عدم التجانس التي هي خارجي لتكوين الأنواع في المجتمع. نحن نقدم طرق تفصيلية جديدة لخلق تجانس التربة باستخدام العلاجات التربة الموضوع إلى التربة النباتية تكييف ردود الفعل، أو ع...

Video: Experimental Protocol for Manipulating Plant-induced Soil Heterogeneity

Design and Operation of a Continuous 13C and 15N Labeling Chamber for Uniform or Differential, Metabolic and Structural, Plant Isotope Labeling

Tracing rare stable isotopes from plant material through the ecosystem provides the most sensitive information about ecosystem processes; from CO2 fluxes and soil organic matter formation to small-scale stable-isotope biomarker probing. Coupling multiple stable isotopes such as 13C with 15N, 18O or&#160;2H has the potential to reveal even more information about complex stoichiometric relationships during biogeochemical transformations. Isotope labeled plant material has been used in various studies of litter decomposition and soil organic matter formation1-4. From these and other studies, however, it has become apparent that structural components of plant material behave differently than metabolic components (i.e. leachable low molecular weight compounds) in terms of microbial utilization and long-term carbon storage5-7. The ability to study structural and metabolic components separately provides a powerful new tool for advancing the forefront of ecosystem biogeochemical studies. Here we describe a method for producing 13C and 15N labeled plant material that is either uniformly labeled throughout the plant or differentially labeled in structural and metabolic plant components.
Here, we present the construction and operation of a continuous 13C and 15N labeling chamber that can be modified to meet various research needs. Uniformly labeled plant material is produced by continuous labeling from seedling to harvest, while differential labeling is achieved by removing the growing plants from the chamber weeks prior to harvest. Representative results from growing Andropogon gerardii Kaw demonstrate the system&#39;s ability to efficiently label plant material at the targeted levels. Through this method we have produced plant material with a 4.4 atom%13C and 6.7 atom%15N uniform plant label, or material that is differentially labeled by up to 1.29 atom%13C and 0.56 atom%15N in its metabolic and structural components (hot water extractable and hot water residual components, respectively). Challenges lie in maintaining proper temperature, humidity, CO2 concentration,&#160;and light levels in an airtight 13C-CO2 atmosphere for successful plant production. This chamber description represents a useful research tool to effectively produce uniformly or differentially multi-isotope labeled plant material for use in experiments on ecosystem biogeochemical cycling.

Design and Operation of a Continuous 13C and 15N Labeling Chamber for Uniform or Differential, Metabolic and Structural, Plant Isotope Labeling

This method explains how to build and operate a continuous 13C and 15N isotope labeling chamber for uniform or differential plant tissue labeling. Representative results from metabolic and structural labeling of Andropogon gerardii are discussed.

تصميم وتشغيل المستمر<sup&gt; 13</sup&gt; C و<sup&gt; 15</sup&gt; N غرفة صفها الموحدة لأو التفاضلية، الأيض والإنشائية، مصنع النظائر وصفها

Tracing rare stable isotopes from plant material through the ecosystem provides the most sensitive information about ecosystem processes; from CO2 fluxes ...

A Protocol for Conducting Rainfall Simulation to Study Soil Runoff

Rainfall is a driving force for the transport of environmental contaminants from agricultural soils to surficial water bodies via surface runoff. The objective of this study was to characterize the effects of antecedent soil moisture content on the fate and transport of surface applied commercial urea, a common form of nitrogen (N) fertilizer, following a rainfall event that occurs within 24&#160;hr&#160;after fertilizer application. Although urea is assumed to be readily hydrolyzed to ammonium and therefore not often available for transport, recent studies suggest that urea can be transported from agricultural soils to coastal waters where it is implicated in harmful algal blooms. A rainfall simulator was used to apply a consistent rate of uniform rainfall across packed soil boxes that had been prewetted to different soil moisture contents. By controlling rainfall and soil physical characteristics, the effects of antecedent soil moisture on urea loss were isolated. Wetter soils exhibited shorter time from rainfall initiation to runoff initiation, greater total volume of runoff, higher urea concentrations in runoff, and greater mass loadings of urea in runoff. These results also demonstrate the importance of controlling for antecedent soil moisture content in studies designed to isolate other variables, such as soil physical or chemical characteristics, slope, soil cover, management, or rainfall characteristics. Because rainfall simulators are designed to deliver raindrops of similar size and velocity as natural rainfall, studies conducted under a standardized protocol can yield valuable data that, in turn, can be used to develop models for predicting the fate and transport of pollutants in runoff.

A rainfall simulator was used to apply a consistent rate of uniform rainfall to packed soil boxes in a study of the fate and transport of urea, a nonpoint source environmental contaminant. Under uniform soil and rainfall conditions, antecedent soil moisture content exerted strong control over urea loss in surface runoff.

بروتوكول لإجراء محاكاة لدراسة هطول الأمطار والجريان السطحي للتربة

Rainfall is a driving force for the transport of environmental contaminants from agricultural soils to surficial water bodies via surface runoff. The ...

A Protocol for Collecting and Constructing Soil Core Lysimeters

Leaching of nutrients from land applied fertilizers and manure used in agriculture can lead to accelerated eutrophication of surface water. Because the landscape has complex and varied soil morphology, an accompanying disparity in flow paths for leachate through the soil macropore and matrix structure is present. The rate of flow through these paths is further affected by antecedent soil moisture. Lysimeters are used to quantify flow rate, volume of water and concentration of nutrients leaching downward through soils. While many lysimeter designs exist, accurately determining the volume of water and mass balance of nutrients is best accomplished with bounded lysimeters that leave the natural soil structure intact. 
Here we present a detailed method for the extraction and construction of soil core lysimeters equipped with soil moisture sensors at 5 cm and 25 cm depths. Lysimeters from four different Coastal Plain soils (Bojac, Evesboro, Quindocqua and Sassafras) were collected on the Delmarva Peninsula and moved to an indoor climate controlled facility. Soils were irrigated once weekly with the equivalent of 2 cm of rainfall to draw down soil nitrate-N concentrations. At the end of the draw down period, poultry litter was applied (162 kg TN ha-1) and leaching was resumed for an additional five weeks. Total recovery of applied irrigation water varied from 71% to 85%. Nitrate-N concentration varied over the course of the study from an average of 27.1 mg L-1 before litter application to 40.3 mg L-1 following litter application. While greatest flux of nutrients was measured in soils dominated by coarse sand (Sassafras) the greatest immediate flux occurred from the finest textured soil with pronounced macropore development (Quindocqua).

A detailed method for extraction and assembly of intact soil core lysimeters and their use for study of leachate and associated loss of nutrients from surface applied poultry litter is demonstrated.

بروتوكول لجمع وبناء Lysimeters الأساسية التربة

Leaching of nutrients from land applied fertilizers and manure used in agriculture can lead to accelerated eutrophication of surface water. Because the ...

Experimental Protocol for Biodiesel Production with Isolation of Alkenones as Coproducts from Commercial Isochrysis Algal Biomass

The need to replace petroleum fuels with alternatives from renewable and more environmentally sustainable sources is of growing importance. Biomass-derived biofuels have gained considerable attention in this regard, however first generation biofuels from edible crops like corn ethanol or soybean biodiesel have generally fallen out of favor. There is thus great interest in the development of methods for the production of liquid fuels from domestic and superior non-edible sources. Here we describe a detailed procedure for the production of a purified biodiesel from the marine microalgae Isochrysis. Additionally, a unique suite of lipids known as polyunsaturated long-chain alkenones are isolated in parallel as potentially valuable coproducts to offset the cost of biodiesel production. Multi-kilogram quantities of Isochrysis are purchased from two commercial sources, one as a wet paste (80% water) that is first dried prior to processing, and the other a dry milled powder (95% dry). Lipids are extracted with hexanes in a Soxhlet apparatus to produce an algal oil (&#34;hexane algal oil&#34;) containing both traditional fats (i.e., triglycerides, 46-60% w/w) and alkenones (16-25% w/w). Saponification of the triglycerides in the algal oil allows for separation of the resulting free fatty acids (FFAs) from alkenone-containing neutral lipids. FFAs are then converted to biodiesel (i.e., fatty acid methyl esters, FAMEs) by acid-catalyzed esterification while alkenones are isolated and purified from the neutral lipids by crystallization. We demonstrate that biodiesel from both commercial Isochrysis biomasses have similar but not identical FAME profiles, characterized by elevated polyunsaturated fatty acid contents (approximately 40% w/w). Yields of biodiesel were consistently higher when starting from the Isochrysis wet paste (12% w/w vs. 7% w/w), which can be traced to lower amounts of hexane algal oil obtained from the powdered Isochrysis product.

Experimental Protocol for Biodiesel Production with Isolation of Alkenones as Coproducts from Commercial Isochrysis Algal Biomass

Detailed methods are presented for the production of biodiesel along with the co-isolation of alkenones as valuable coproducts from commercial Isochrysis microalgae.

البروتوكول التجريبي لإنتاج الديزل الحيوي مع عزل Alkenones كما Coproducts من التجاري<em&gt; ذهبي متساوي</em&gt; الطحالب الكتلة الحيوية

The need to replace petroleum fuels with alternatives from renewable and more environmentally sustainable sources is of growing importance. ...

A Gusseted Thermogradient Table to Control Soil Temperatures for Evaluating Plant Growth and Monitoring Soil Processes

Thermogradient tables were first developed in the 1950s primarily to test seed germination over a range of temperatures simultaneously without using a series of incubators. A temperature gradient is passively established across the surface of the table between the heated and cooled ends and is lost quickly at distances above the surface. Since temperature is only controlled on the table surface, experiments are restricted to shallow containers, such as Petri dishes, placed on the table. Welding continuous aluminum vertical strips or gussets perpendicular to the surface of a table enables temperature control in depth via convective heat flow. Soil in the channels between gussets was maintained across a gradient of temperatures allowing a greater diversity of experimentation. The gusseted design was evaluated by germinating oat, lettuce, tomato, and melon seeds. Soil temperatures were monitored using individual, battery-powered dataloggers positioned across the table. LED lights installed in the lids or along the sides of the gradient table create a controlled temperature chamber where seedlings can be grown over a range of temperatures. The gusseted design enabled accurate determination of optimum temperatures for fastest germination rate and the highest percentage germination for each species. Germination information from gradient table experiments can help predict seed germination and seedling growth under the adverse soil conditions often encountered during field crop production. Temperature effects on seed germination, seedling growth, and soil ecology can be tested under controlled conditions in a laboratory using a gusseted thermogradient table.

Traditional thermogradient tables create a range of temperatures across the surface. Welding gussets perpendicular to the surface of a thermogradient table will control temperature in depth increasing possible research applications.

والجدول Gusseted Thermogradient لتنظيم درجة الحرارة التربة لتقييم نمو النبات ومراقبة العمليات التربة

Thermogradient tables were first developed in the 1950s primarily to test seed germination over a range of temperatures simultaneously without using a ...

Experimental Protocol for Detecting Cyanobacteria in Liquid and Solid Samples with an Antibody Microarray Chip

Global warming and eutrophication make some aquatic ecosystems behave as true bioreactors that trigger rapid and massive cyanobacterial growth; this has relevant health and economic consequences. Many cyanobacterial strains are toxin producers, and only a few cells are necessary to induce irreparable damage to the environment. Therefore, water-body authorities and administrations require rapid and efficient early-warning systems providing reliable data to support their preventive or curative decisions. This manuscript reports an experimental protocol for the in-field detection of toxin-producing cyanobacterial strains by using an antibody microarray chip with 17 antibodies (Abs) with taxonomic resolution (CYANOCHIP). Here, a multiplex fluorescent sandwich microarray immunoassay (FSMI) for the simultaneous monitoring of 17 cyanobacterial strains frequently found blooming in freshwater ecosystems, some of them toxin producers, is described. A microarray with multiple identical replicates (up to 24) of the CYANOCHIP was printed onto a single microscope slide to simultaneously test a similar number of samples. Liquid samples can be tested either by direct incubation with the antibodies (Abs) or after cell concentration by filtration through a 1- to 3-&#956;m filter. Solid samples, such as sediments and ground rocks, are first homogenized and dispersed by a hand-held ultrasonicator in an incubation buffer. They are then filtered (5 - 20 &#956;m) to remove the coarse material, and the filtrate is incubated with Abs. Immunoreactions are revealed by a final incubation with a mixture of the 17 fluorescence-labeled Abs and are read by a portable fluorescence detector. The whole process takes around 3 h, most of it corresponding to two 1-h periods of incubation. The output is an image, where bright spots correspond to the positive detection of cyanobacterial markers.

Experimental Protocol for Detecting Cyanobacteria in Liquid and Solid Samples with an Antibody Microarray Chip

The presence of cyanobacterial toxins in fresh water reservoirs for human consumption is a major concern for water management authorities. To evaluate the risk of water contamination, this article describes an protocol for the in-field detection of cyanobacterial strains in liquid and solid samples by using an antibody microarray chip.

بروتوكول تجريبي للكشف<em&gt; البكتيريا الزرقاء</em&gt; في العينات السائلة والصلبة مع الأجسام المضادة ميكروأري رقاقة

Global warming and eutrophication make some aquatic ecosystems behave as true bioreactors that trigger rapid and massive cyanobacterial growth; this has ...

Protocols for Quantifying Transferable Pesticide Residues in Turfgrass Systems

Plant canopies in established turfgrass systems can intercept an appreciable amount of sprayed pesticides, which can be transferred through various routes onto humans. For this reason, transferable pesticide residue experiments are required for registration and re-registration by the United States Environmental Protection Agency (USEPA). Although such experiments are required, limited specificity is required pertaining to experimental approach. Experimental approaches used to assess pesticide transfer to humans including hand wiping with cotton gloves, modified California roller (moving a roller of known mass over cotton cloth) and soccer ball roll (ball wrapped with sorbent strip) over three treated turfgrass species (creeping bentgrass, hybrid bermudagrass and tall fescue maintained at 0.4, 5 and 9 cm, respectively) are presented. The modified California roller is the most extensively utilized approach to date, and is best suited for use at low mowing heights due to its reproducibility and large sampling area. The soccer ball roll is a less aggressive transfer approach; however, it mimics a very common occurrence in the most popular international sport, and has many implications for nondietary pesticide exposure from hand-to-mouth contact. Additionally, this approach may be adjusted for other athletic activities with limited modification. Hand wiping is the best approach to transfer pesticides at higher mowing heights, as roller-based approaches can lay blades over; however, it is more subjective due to more variable sampling pressure. Utility of these methods across turfgrass species is presented, and additional considerations to conduct transferable pesticide residue research in turfgrass systems are discussed.

Transferable pesticide residue experiments in turfgrass systems are integral components of human risk exposure assessments. Experimental approaches to measure transferable residues should be adjusted to the human interaction of interest and turfgrass system dynamics. Three transferable pesticide residue protocols are presented and the suitability across three turfgrass systems is discussed.

بروتوكولات لقياس متبقيات المبيدات القابلة للتحويل في أنظمة المروج

Plant canopies in established turfgrass systems can intercept an appreciable amount of sprayed pesticides, which can be transferred through various routes ...

Nanopore DNA Sequencing for Metagenomic Soil Analysis

This article describes the steps for construction of a DNA library from soil, preparation and use of the nanopore flow cell, and analysis of the DNA sequences identified using computer software. Nanopore DNA sequencing is a flexible technique that allows for rapid microbial genome sequencing to identify bacterial and viral species, to characterize bacterial strains, and to detect genetic mutations that confer resistance to antibiotics. The advantages of nanopore sequencing (NS) for life sciences include its low complexity, reduced cost, and rapid real-time sequencing of purified genomic DNA, PCR amplicons, cDNA samples, or RNA. NS is an example of "strand sequencing" which involves sequencing DNA by guiding a single stranded DNA molecule through a nanopore that is inserted into a synthetic polymer membrane. The membrane has an electrical current applied across it, so as the individual bases pass through the nanopore the electrical current is disrupted to varying degrees by the four nucleotide bases. The identification of each nucleotide occurs by detecting the characteristic modulation of the electrical current by the different bases as they pass through the nanopore. The NS system consists of a handheld, USB powered portable device and a disposable flow cell that contains a nanopore array. The portable device plugs into a standard laptop computer that reads and records the DNA sequence using computer software.

Nanopore technology for sequencing biomolecules has wide applications in the life sciences, including identification of pathogens, food safety monitoring, genomic analysis, metagenomic environmental monitoring, and characterization of bacterial antibiotic resistance. In this article, the procedure for metagenomic soil DNA sequencing for species identification using the nanopore sequencing technology is demonstrated.

نانوبوري تسلسل الحمض النووي لتحليل التربة الجينومية

This article describes the steps for construction of a DNA library from soil, preparation and use of the nanopore flow cell, and analysis of the DNA ...

Measuring and Mapping Patterns of Soil Erosion and Deposition Related to Soil Carbonate Concentrations Under Agricultural Management

Spatial patterns of soil erosion and deposition can be inferred from differences in ground elevation mapped at appropriate time increments. Such changes in elevation are related to changes in near-surface soil carbonate (CaCO3) profiles. The objective is to describe a simple conceptual model and detailed protocol for repeatable field and laboratory measurements of these quantities. Here, accurate elevation is measured using a ground-based differential global positioning system (GPS); other data acquisition methods could be applied to the same basic method. Soil samples are collected from prescribed depth intervals and analyzed in the lab using an efficient and precise modified pressure-calcimeter method for quantitative analysis of inorganic carbon concentration. Standard statistical methods are applied to point data, and representative results show significant correlations between changes in soil surface layer CaCO3 and changes in elevation consistent with the conceptual model; CaCO3 generally decreased in depositional areas and increased in erosional areas. Maps are derived from point measurements of elevation and soil CaCO3 to aid analyses. A map of erosional and depositional patterns at the study site, a rain-fed winter wheat field cropped in alternating wheat-fallow strips, shows the interacting effects of water and wind erosion affected by management and topography. Alternative sampling methods and depth intervals are discussed and recommended for future work relating soil erosion and deposition to soil CaCO3.

Spatial patterns of soil erosion and deposition can be inferred from differences in ground elevation mapped at appropriate time increments. Such changes in elevation are related to changes in near-surface soil carbonates. Repeatable methods for field and laboratory measurements of these quantities and data analysis methods are described here.

قياس وتحديد أنماط من تآكل التربة وترسب المتصلة بتركيزات كربونات التربة تحت الإدارة الزراعية

Spatial patterns of soil erosion and deposition can be inferred from differences in ground elevation mapped at appropriate time increments. Such changes ...

Experimental Protocol for Detecting Mitochondrial Function in Hepatocytes Exposed to Organochlorine Pesticides

This paper presents detailed methods on detecting hepatic mitochondrial function for a better understanding the cause of metabolic disorders caused by environmental organochlorine pesticides (OCPs) in hepatocytes. HepG2 cells were exposed to &#946;-hexachlorocyclohexane (&#946;-HCH) for 24 h at an equivalent dose of internal exposure in general population. Ultrastructure in hepatocytes was examined by transmission electron microscopy (TEM) to show the damage of mitochondria. Mitochondrial function was further evaluated by mitochondrial fluorescence intensity, adenosine 5'-triphosphate (ATP) levels, oxygen consumption rate (OCR) and mitochondrial membrane potential (MMP) in HepG2 cells incubated with &#946;-HCH. The mitochondria fluorescence intensity after stained by mitochondrial green fluorescent probe was observed with a fluorescence microscopy. The luciferin-luciferase reaction was used to determine ATP levels. The MMP was detected by the cationic dye JC-1 and analyzed under flow cytometry. OCR was measured with an extracellular flux analyzer. In summary, these protocols were used in detecting mitochondrial function in hepatocytes with to investigate mitochondria damages.

Understanding the influence of environmental organochlorine pesticides (OCPs) on mitochondrial function in hepatocytes is important in exploring the mechanism of OCPs causing metabolic disorders. This paper presents detailed methods on detecting hepatic mitochondrial function.

البروتوكول التجريبي للكشف عن وظيفة الميتوكوندريا في خلايا الكبد المعرضة لمبيدات الآفات أورجاكلوري

This paper presents detailed methods on detecting hepatic mitochondrial function for a better understanding the cause of metabolic disorders caused by ...