Name: a low-cost method of measuring the in situ primary productivity of periphyton communities of lentic waters
Uploaded: 2022-12-16T13:05:00
Description: Watch this Scientific Journal Video about A Low-Cost Method of Measuring the In Situ Primary Productivity of Periphyton Communities of Lentic Waters at JoVE.com

This study was supported by the Czech Science Foundation (GACR 19-05791S), RVO 67985939, and by the CAS within the program of the Strategy AV 21, Land save and recovery. Many thanks to Ond&#345;ej Sihelsk&#253; for taking the shots in the field - without him, the filming would have been complete hell. The project would not be possible without tight cooperation with companies, Palivov&#253; Kombin&#225;t &#218;st&#237; s.p. and Sokolovsk&#225; Uheln&#225;, who provided access to the studied localities.

NOTE: Before sampling, determine the degree of replications based on the overall project needs, statistical design, or expected amount of sample variability.Five replicate pairs of light and dark incubation bottles are suggested for precise statistical analysis and to account for potential sample loss or breakage. The described floating experimental barge is designed to carry five replicates plus one pair of blank controls; see Figure 1 for a technical drawing of the experimental barge.
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<ol>
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The methodology described in this paper is based on the principle of the light and dark bottle oxygen technique in combination with the noninvasive technique of measuring O2 concentration using optical oxygen sensors. This system allows the parallel measurement of different incubation settings as the optical fiber for measuring O2 can be moved quickly from bottle to bottle. The benthic communities from various depths can differ in taxonomic composition and productivity; simultaneously measuring them...

Primary productivity is the only entry of autochthonous carbon into the aquatic systems that form the entire system food web1. Hence, the accurate estimation of primary productivity is an essential step toward understanding the functioning of aquatic ecosystems. Littoral zones are areas of high primary productivity and biodiversity. In addition to phytoplankton, periphyton (hereafter referred to as microbial mats) and macroalgae are assumed to significantly contribute to primary productivity in littoral zones2. Due to their sessile lifestyle and significant spatial heterogeneity, quantification of primary productivity is not trivial. 
Primary productivity is driven mainly by light intensity, temperature, availability of nutrients, and distribution of the ionic species of the carbonate system in the respective depths of euphotic zones3,4. The depth markedly influences the spatial distribution of microbial mats. Microbial communities must cope with the adverse effects of high irradiation and pronounced seasonal temperature variations in shallow depths and with lower light intensity at greater depths. In addition to the depth gradient, dynamic trophic interactions generate multiple and complex spatial patterns at different scales5. This complex system is complicated to simulate in the laboratory. The most accurate way to infer the metabolic activity of individual primary producers from littoral zones is to set up in situ experiments. 
The methodology introduced in this paper is based on the traditional chamber method2,6,7, together with a transportable and easy-to-build low-cost floating barge. This allows the measurement of primary productivity at different depths under the natural light spectrum, temperature, and different distribution of the ionic species of the carbonate system with the depth. The method is based on the principle of light versus dark bottle oxygen, which was first employed to measure phytoplankton photosynthesis6 and is still commonly used6,7. It compares the rate of change in oxygen in bottles kept in the light (which includes the effects of primary productivity and respiration) with those held in the dark (respiration only)8. The method uses oxygen evolution (photosynthesis) as a proxy for primary productivity. The measured variables are net ecosystem productivity (NEP, as a change in O2 concentration over time in light conditions) and ecosystem respiration (RE, as a change in O2 concentration over time in the dark). Gross ecosystem productivity (GEP) is the calculation of the difference between the two (Table 1). The term "ecosystem" is used here to denote that the periphyton is composed of autotrophic and heterotrophic organisms. The most significant improvement of this traditional chamber method is using noninvasive oxygen optical sensors and optimization of this primarily planktonic method for measuring periphytic primary productivity.
The technique is described in the example of measuring microbial mats in the littoral zone of newly emerged post-mining lakes in the Czech Republic-Milada, Most, and Medar. The metabolic activity of microbial mats is determined using direct in situ measurement of O2 fluxes performed directly at specific depths, where the studied communities naturally occur. Heterotrophic and phototrophic activity is measured in closed glass bottles equipped with noninvasive optical oxygen sensors. These sensors detect the partial pressure of oxygen using the fluorescence of light-sensitive dyes. The bottles with microbial mats are suspended and incubated on a floating device at the appropriate depths. The oxygen concentration inside the bottles was continuously measured during the daylight period from the small boat. 
Samples of intact microbial mats are collected and placed in gas-tight incubation bottles at designated depths by scuba divers. Each bottle is equipped with a noninvasive optical oxygen microsensor, which monitors the O2 productivity/consumption over time. All measurements are done in five replicate dark/light pairs in each depth. The temperature and photosynthetically active radiation (PHAR) intensities are measured at respective depths throughout the incubation. After 6 h of in situ incubation (daylight hours), the microbial mats are harvested from the bottles and dried. O2 fluxes are normalized to microbial biomass. As a control, fluxes are corrected for changes in O2 concentration in separate light and dark gas-tight bottles (blank controls) containing lake water without microbial mat biomass. Below are detailed instructions for building the floating barge and performing the whole experiment step-by-step. This paper also presents representative results from the measurements of microbial mats at two depths (1 m and 2 m), with five replicates at each depth. Actual temperature and light intensity were measured during the whole experiment using dataloggers.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Aluminum angle L profile 40 x 40 mm x 3 mm, length 2,000 mm</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Aluminum flat bar 40 x 3 x 350 mm</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Bucket 15 L with concrete infill&#160;</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Carabine hook with screw lock 50 x 5 mm</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>electric tape black</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Extruded polystyrene (XPS) material 500 x 200 x 150 mm</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Fibox 3 LCD trace</td>
			<td>PreSens Precision Sensing GmbH</td>
			<td></td>
			<td>stand-alone fiber optic oxygen meter</td>
		</tr>
		<tr>
			<td>Hondex PS-7 Portable Depth Sounder</td>
			<td>Hondex&#160; - Honda Electronics</td>
			<td></td>
			<td>to measures distances through water - to bottom depth measurement; https://www.honda-el.net/industry/ps-7e</td>
		</tr>
		<tr>
			<td>KORKEN - glass tight-seal jar 0.5 L</td>
			<td>IKEA</td>
			<td></td>
			<td>incubation bottles; https://www.ikea.com/cz/en/p/korken-jar-with-lid-clear-glass-70213545/</td>
		</tr>
		<tr>
			<td>metal hook&#160;</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Oxygen Sensor Spot SP-PSt3-NAU-D5</td>
			<td>PreSens Precision Sensing GmbH</td>
			<td></td>
			<td>non-invasive optical oxygen sensor for measurements under Real Conditions</td>
		</tr>
		<tr>
			<td>SCOUT infantable canoe</td>
			<td>GUMOTEX</td>
			<td></td>
			<td>https://www.gumotexboats.com/en/scout-standard#0000-044667-021-13/11C</td>
		</tr>
		<tr>
			<td>Screw 10 x 170 mm with hexagonal nuts</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Screw 4 x 15 mm with hexagonal nuts</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Screw 4 x 15 mm with wing nuts</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Snap hooks 50 x 5 mm</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Steel Carabine hook 50 x 5 mm</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Steel chain with wire diameter 3 mm, inside link 5.5 x 26 mm</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Steel chain, 5 m</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>toothbrush</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>tweezer</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Washer 10 x 50 mm</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Washer 4 x 10 mm</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Washer 4 x 10 mm</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

a low-cost method of measuring the in situ primary productivity of periphyton communities of lentic waters

Measuring the in situ primary productivity of periphyton during the growing season gradient can elucidate the quantitative effect of environmental drivers (mainly phosphorus concentration and light intensity) and species composition on primary productivity. Primary productivity is mainly driven by light intensity, temperature, availability of nutrients, and distribution of the ionic species of the carbonate system in the respective depths of the euphotic zone. It is a complex system that is very difficult to simulate in the laboratory. This cheap, transportable, and easy-to-build floating barge allows measuring the primary productivity accurately-directly under the actual natural conditions. The methodology is based on measuring the primary productivity in real time using noninvasive oxygen sensors integrated into tightly sealed glass jars, enabling online oxygen flux monitoring and providing new insights into metabolic activities. Detailed seasonal in situ measurements of gross primary productivity of microbial mats (or other benthic organisms) can improve current knowledge of the processes controlling primary productivity dynamics in lentic waters.

<img alt="Figure 5" class="xfigimg" src="/files/ftp_upload/64078/64078fig05.jpg" /> 
Figure 5: Net and gross ecosystem productivity of microbial mats during daylight. (A) Light bottle-net ecosystem productivity: time course data of net oxygen productivity of microbial mats from the light bottles. The oxygen concentration change in incubation bottles was measured after 1 h during daylight. Grey circles: bottles with samples of m...

Watch this Scientific Journal Video about A Low-Cost Method of Measuring the In Situ Primary Productivity of Periphyton Communities of Lentic Waters at JoVE.com

A Low-Cost Method of Measuring the In Situ Primary Productivity of Periphyton Communities of Lentic Waters

Presented here is a cost-effective and transportable method/facility for measuring the primary productivity of microbial mats under actual in situ environmental temperature and light conditions. The experimental setup is based on widely available materials and can be used under various conditions while offering the advantages of laboratory-based models.

A Low-Cost Method of Measuring the In Situ Primary Productivity of Periphyton Communities of Lentic Waters

Measuring the in situ primary productivity of periphyton during the growing season gradient can elucidate the quantitative effect of environmental drivers ...

Detailed in-situ measurement of the gross productivity of periphyton or any water microorganism in a suitable site can improve current knowledge of the processes controlling primary productivity dynamic in lentic waters. The major improvements in the proposed methods are non-invasiveness, cost-effectiveness, and the possibility of simultaneous measurements in various location. It also enables the collection of large data assets without additional expenses.Replacing the barge in conducting the experiments, use an inflatable kayak as it's easily transportable. Select a place with an ideal depth to anchor the float. Next, attach the assembled barge behind the stern of the boat and carefully lower the anchor along the side of the boat.Align the anchor by hanging it slightly below the water surface so that the float can be easily towed with the anchor to the spot with the required depth. After reaching the spot, untie the anchor from the boat and lower it to the bottom, then secure the barge to the anchor chain and the chains for attaching the incubation bottles to the barge. To prepare the incubation bottles, attach oxygen optical sensor spots to the inner wall of transparent, wide-neck 0.5-liter bottles with gas-tight seals, then make an opaque layer for the dark treatment bottles by wrapping them with black electrical tape.Cut a tiny hole in the spot of the placed optical sensor and ensure that the cut hole is slightly smaller than the diameter of the sensor to prevent light from entering the bottle. Place the incubation bottles in the portable box and dive with the box to the respective depth without disturbing the sediment in the surrounding water. Next, using long tweezers, carefully fill the samples into the incubation bottles, taking care not to disturb the biomass of the sample too much.If the microbial mats grow on a solid surface such as a small stone, carefully transfer the whole stone with intact biomass into the bottle. Fill one pair of light and dark bottles with clean water from the respective depths without any sediments to serve as blank controls. After ensuring that the water in all incubation bottles is clean and contains no disturbing sediment, bring the closed bottles to the boat anchored to the floating barge.Attach the first two pairs of incubation bottles to the snap hooks on the first chain, then measure the initial oxygen concentration in each bottle using the fiber-optic oxygen meter. Attach the optical cable of the meter to the oxygen sensor mounted inside the bottle and within a few seconds, read out the oxygen concentration in the meter and record the measured value. Immediately after measurement, carefully lower the chain with the attached bottles back into the water, ensuring that the incubation bottles are placed at the same depth from which the biomass placed in them was sampled.After one hour, measure the oxygen concentration again by carefully pulling each chain with the bottles into the boat. Reading the oxygen value was demonstrated previously and lowering the samples into the water again. After completing all the measurements, take the samples out from the incubation bottles and scrub the microbial mat grown on the surface of a hard substance like stone with a toothbrush or small knife, then transfer the contents to plastic flasks.An increase in the oxygen concentration over time is apparent in both the control and the sample bottles exposed to light indicating net ecosystem productivity. Nevertheless, the slope of increase is significantly higher in bottles with microbial mat samples. The change in the oxygen concentration over time in the dark bottles is the sum of autotrophic and heterotrophic respiration.In this case, the slope of oxygen concentration in the control bottle is not significantly different from zero. Subtracting the respiration rates from net ecosystem productivity yields the rates of gross ecosystem productivity and the data complies well with the definition. A practical application of this method was achieved in the fields of three post-mining lakes that show the gross ecosystem productivity of the periphytic community during the vegetation season.During the biomass sampling process underwater, it is important to ensure that no air bubbles remain trapped inside the incubation bottles once they are closed after adding the samples. Using this procedure, it is possible to quantify oxygen exchange between the water body and any organism or community of organisms of a suitable size. This method allows studying the year-round primary productivity of selected organism in situ by making the natural condition as much as possible, thus giving a better idea of its relative importance for whole-life carbon metabolism.

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Determination of Microbial Extracellular Enzyme Activity in Waters, Soils, and Sediments using High Throughput Microplate Assays

Much of the nutrient cycling and carbon processing in natural environments occurs through the activity of extracellular enzymes released by microorganisms. Thus, measurement of the activity of these extracellular enzymes can give insights into the rates of ecosystem level processes, such as organic matter decomposition or nitrogen and phosphorus mineralization. Assays of extracellular enzyme activity in environmental samples typically involve exposing the samples to artificial colorimetric or fluorometric substrates and tracking the rate of substrate hydrolysis. Here we describe microplate based methods for these procedures that allow the analysis of large numbers of samples within a short time frame. Samples are allowed to react with artificial substrates within 96-well microplates or deep well microplate blocks, and enzyme activity is subsequently determined by absorption or fluorescence of the resulting end product using a typical microplate reader or fluorometer. Such high throughput procedures not only facilitate comparisons between spatially separate sites or ecosystems, but also substantially reduce the cost of such assays by reducing overall reagent volumes needed per sample.

Microplate based procedures are described for the colorimetric or fluorometric analysis of extracellular enzyme activity. These procedures allow for the rapid assay of such activity in large numbers of environmental samples within a manageable time frame.

Much of the nutrient cycling and carbon  processing in natural environments occurs through the activity of extracellular  enzymes released by ...

A Noninvasive Method For In situ Determination of Mating Success in Female American Lobsters (Homarus americanus)

Despite being one of the most productive fisheries in the Northwest Atlantic, much remains unknown about the natural reproductive dynamics of American lobsters. Recent work in exploited crustacean populations (crabs and lobsters) suggests that there are circumstances where mature females are unable to achieve their full reproductive potential due to sperm limitation. To examine this possibility in different regions of the American lobster fishery, a reliable and noninvasive method was developed for sampling large numbers of female lobsters at sea. This method involves inserting a blunt-tipped needle into the female&#39;s seminal receptacle to determine the presence or absence of a sperm plug and to withdraw a sample that can be examined for the presence of sperm. A series of control studies were conducted at the dock and in the laboratory to test the reliability of this technique. These efforts entailed sampling 294 female lobsters to confirm that the presence of a sperm plug was a reliable indicator of sperm within the receptacle and thus, mating. This paper details the methodology and the results obtained from a subset of the total females sampled. Of the 230 female lobsters sampled from George&#39;s Bank and Cape Ann, MA (size range = 71-145 mm in carapace length), 90.3% were positive for sperm. Potential explanations for the absence of sperm in some females include: immaturity (lack of physiological maturity), breakdown of the sperm plug after being used to fertilize a clutch of eggs, and lack of mating activity. The surveys indicate that this technique for examining the mating success of female lobsters is a reliable proxy that can be used in the field to document reproductive activity in natural populations.

A Noninvasive Method For In situ Determination of Mating Success in Female American Lobsters Homarus americanus

Fishery-induced changes to exploited crustacean fisheries, such as the American lobster fishery, could potentially influence their reproductive dynamics, leading to a reduction in mating success. This study&#39;s goal was to develop a noninvasive method for ascertaining the mating success of female lobsters that may be physiologically or functionally mature.

Despite being one of the most productive fisheries in the Northwest Atlantic, much remains unknown about the natural reproductive dynamics of American ...

Quantification of Heavy Metals and Other Inorganic Contaminants on the Productivity of Microalgae

Increasing demand for renewable fuels has researchers investigating the feasibility of alternative feedstocks, such as microalgae. Inherent advantages include high potential yield, use of non-arable land and integration with waste streams. The nutrient requirements of a large-scale microalgae production system will require the coupling of cultivation systems with industrial waste resources, such as carbon dioxide from flue gas and nutrients from wastewater. Inorganic contaminants present in these wastes can potentially lead to bioaccumulation in microalgal biomass negatively impact productivity and limiting end use. This study focuses on the experimental evaluation of the impact and the fate of 14 inorganic contaminants (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Sb, Se, Sn, V and Zn) on Nannochloropsis salina growth. Microalgae were cultivated in photobioreactors illuminated at 984 &#181;mol m-2 sec-1 and maintained at pH 7 in a growth media polluted with inorganic contaminants at levels expected based on the composition found in commercial coal flue gas systems. Contaminants present in the biomass and the medium at the end of a 7 day growth period were analytically quantified through cold vapor atomic absorption spectrometry for Hg and through inductively coupled plasma mass spectrometry for As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sb, Se, Sn, V and Zn. Results show N. salina is a sensitive strain to the multi-metal environment with a statistical decrease in biomass yieldwith the introduction of these contaminants. The techniques presented here are adequate for quantifying algal growth and determining the fate of inorganic contaminants.

Integration of microalgal cultivation with industrial flue gas will ultimately introduce heavy metals and other inorganic compounds into the growth media. This study presents a procedure used to determine the end fate and impact of heavy metals and inorganic contaminants on the growth of Nannochloropsis salina grown in photobioreactors.

Increasing demand for renewable fuels has researchers investigating the feasibility of alternative feedstocks, such as microalgae. Inherent advantages ...

Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies

Most of the trace metal concentrations in ambient waters obtained a few decades ago have been considered unreliable owing to the lack of contamination control. Developments of some techniques aiming to reduce trace metal contamination in the last couple of decades have resulted in concentrations reported now being orders of magnitude lower than those in the past. These low concentrations often necessitate preconcentration of water samples prior to instrumental analysis of samples. Since contamination can appear in all phases of trace metal analyses, including sample collection (and during preparation of sampling containers), storage and handling, pretreatments, and instrumental analysis, specific care needs to be taken in order to reduce contamination levels at all steps. The effort to develop and utilize "clean techniques" in trace metal studies allows scientists to investigate trace metal distributions and chemical and biological behavior in greater details. This advancement also provides the required accuracy and precision of trace metal data allowing for environmental conditions to be related to trace metal concentrations in aquatic environments.
This protocol that is presented here details needed materials for sample preparation, sample collection, sample pretreatment including preconcentration, and instrumental analysis. By reducing contamination throughout all phases mentioned above for trace metal analysis, much lower detection limits and thus accuracy can be achieved. The effectiveness of "clean techniques" is further demonstrated using low field blanks and good recoveries for standard reference material. The data quality that can be obtained thus enables the assessment of trace metal distributions and their relationships to environmental parameters.

Special care using "clean techniques" is required to properly collect and process water samples for trace metal studies in aquatic environments. A protocol for sampling, processing, and analytical procedures with the aim of obtaining reliable environmental monitoring data and results with high sensitivity for detailed trace metal studies is presented.

Most of the trace metal concentrations in ambient waters obtained a few decades ago have been considered unreliable owing to the lack of contamination ...

Pretreatment of Lignocellulosic Biomass with Low-cost Ionic Liquids

A number of ionic liquids (ILs) with economically attractive production costs have recently received growing interest as media for the delignification of a variety of lignocellulosic feedstocks. Here we demonstrate the use of these low-cost protic ILs in the deconstruction of lignocellulosic biomass (Ionosolv pretreatment), yielding cellulose and a purified lignin. In the most generic process, the protic ionic liquid is synthesized by accurate combination of aqueous acid and amine base. The water content is adjusted subsequently. For the delignification, the biomass is placed into a vessel with IL solution at elevated temperatures to dissolve the lignin and hemicellulose, leaving a cellulose-rich pulp ready for saccharification (hydrolysis to fermentable sugars). The lignin is later precipitated from the IL by the addition of water and recovered as a solid. The removal of the added water regenerates the ionic liquid, which can be reused multiple times. This protocol is useful to investigate the significant potential of protic ILs for use in commercial biomass pretreatment/lignin fractionation for producing biofuels or renewable chemicals and materials.

The pretreatment of lignocellulosic biomass with protic low-cost ionic liquids is shown, resulting in a delignified cellulose-rich pulp and a purified lignin. The pulp gives rise to high glucose yields after enzymatic saccharification.

A number of ionic liquids (ILs) with economically attractive production costs have recently received growing interest as media for the delignification of ...

Extraction of Organochlorine Pesticides from Plastic Pellets and Plastic Type Analysis

Plastic resin pellets, categorized as microplastics (&#8804;5 mm in diameter), are small granules that can be unintentionally released to the environment during manufacturing and transport. Because of their environmental persistence, they are widely distributed in the oceans and on beaches all over the world. They can act as a vector of potentially toxic organic compounds (e.g., polychlorinated biphenyls) and might consequently negatively affect marine organisms. Their possible impacts along the food chain are not yet well understood. In order to assess the hazards associated with the occurrence of plastic pellets in the marine environment, it is necessary to develop methodologies that allow for rapid determination of associated organic contaminant levels. The present protocol describes the different steps required for sampling resin pellets, analyzing adsorbed organochlorine pesticides (OCPs) and identifying the plastic type. The focus is on the extraction of OCPs from plastic pellets by means of a pressurized fluid extractor (PFE) and on the polymer chemical analysis applying Fourier Transform-InfraRed (FT-IR) spectroscopy. The developed methodology focuses on 11 OCPs and related compounds, including dichlorodiphenyltrichloroethane (DDT) and its two main metabolites, lindane and two production isomers, as well as the two biologically active isomers of technical endosulfan. This protocol constitutes a simple and rapid alternative to existing methodology for evaluating the concentration of organic contaminants adsorbed on plastic pieces.

Microplastics act as vector of potentially toxic organic contaminants with unpredictable effects. This protocol describes an alternative methodology for assessing the levels of organochlorine pesticides adsorbed on plastic pellets and identifying the polymer chemical structure. The focus is on pressurized fluid extraction and attenuated total reflectance Fourier transform infrared spectroscopy.

Plastic resin pellets, categorized as microplastics (&#8804;5 mm in diameter), are small granules that can be unintentionally released to the environment ...

Measuring the Flight Ability of the Ambrosia Beetle, Platypus Quercivorus (Murayama), Using a Low-Cost, Small, and Easily Constructed Flight Mill

The ambrosia beetle, Platypus quercivorus (Murayama), is the vector of a fungal pathogen that causes mass mortality of Fagaceae trees (Japanese oak wilt). Therefore, knowing the dispersal capacity may help inform trapping/tree removal efforts to prevent this disease more effectively. In this study, we measured the flight velocity and duration and estimated the flight distance of the beetle using a newly developed flight mill. The flight mill is low cost, small, and constructed using commonly available items. Both the flight mill arm and its vertical axis comprise a thin needle. A beetle specimen is glued to one tip of the arm using instant glue. The other tip is thick due to being covered with plastic, thus it facilitates the detection of rotations of the arm. The revolution of the arm is detected by a photo sensor mounted on an infrared LED, and is indicated by a change in the output voltage when the arm passed above the LED. The photo sensor is connected to a personal computer and the output voltage data are stored at a sampling rate of 1 kHz. By conducting experiments using this flight mill, we found that P. quercivorus can fly at least 27 km. Because our flight mill comprises cheap and small ordinary items, many flight mills can be prepared and used simultaneously in a small laboratory space. This enables experimenters to obtain a sufficient amount of data within a short period.

Measuring the Flight Ability of the Ambrosia Beetle, Platypus Quercivorus Murayama, Using a Low-Cost, Small, and Easily Constructed Flight Mill

We developed a low cost and small flight mill, constructed with commonly available items and easily used in experimentation. Using this apparatus, we measured the flight ability of an ambrosia beetle, Platypus quercivorus.

The ambrosia beetle, Platypus quercivorus (Murayama), is the vector of a fungal pathogen that causes mass mortality of Fagaceae trees (Japanese oak wilt). ...

A Flexible Low Cost Hydroponic System for Assessing Plant Responses to Small Molecules in Sterile Conditions

A wide range of studies in plant biology are performed using hydroponic cultures. In this work, an in vitro hydroponic growth system designed for assessing plant responses to chemicals and other substances of interest is presented. This system is highly efficient in obtaining homogeneous and healthy seedlings of the C3 and C4 model species Arabidopsis thaliana and Setaria viridis, respectively. The sterile cultivation avoids algae and microorganism contamination, which are known limiting factors for plant normal growth and development in hydroponics. In addition, this system is scalable, enabling the harvest of plant material on a large scale with minor mechanical damage, as well as the harvest of individual parts of a plant if desired. A detailed protocol demonstrating that this system has an easy and low-cost assembly, as it uses pipette racks as the main platform for growing plants, is provided. The feasibility of this system was validated using Arabidopsis seedlings to assess the effect of the drug AZD-8055, a chemical inhibitor of the target of rapamycin (TOR) kinase. TOR inhibition was efficiently detected as early as 30 min after an AZD-8055 treatment in roots and shoots. Furthermore, AZD-8055-treated plants displayed the expected starch-excess phenotype. We proposed this hydroponic system as an ideal method for plant researchers aiming to monitor the action of plant inducers or inhibitors, as well as to assess metabolic fluxes using isotope-labeling compounds which, in general, requires the use of expensive reagents.

A simple, versatile, and low-cost in vitro hydroponic system was successfully optimized, enabling large-scale experiments under sterile conditions. This system facilitates the application of chemicals in a solution and their efficient absorption by roots for molecular, biochemical, and physiological studies.

A wide range of studies in plant biology are performed using hydroponic cultures. In this work, an in vitro hydroponic growth system designed for ...

Construction of a Compact Low-Cost Radiation Shield for Air-Temperature Sensors in Ecological Field Studies

Low cost temperature sensors are increasingly used by ecologists to assess climatic variation and change on ecologically relevant scales. Although cost-effective, if not deployed with proper solar radiation shielding, the observations recorded from these sensors will be biased and inaccurate. Manufactured radiation shields are effective at minimizing this bias, but are expensive compared to the cost of these sensors. Here, we provide a detailed methodology for constructing a compact version of a previously described custom fabricated radiation shield, which is more accurate than other published shielding methods that attempt to minimize shield size or construction costs. The method requires very little material: corrugated plastic sheets, aluminum foil duct tape, and cable ties. One 15 cm and two 10 cm squares of corrugated plastic are used for each shield. After cutting, scoring, taping and stapling of the sheets, the 10 cm squares form the bottom two layers of the solar radiation shield, while the 15 cm square forms the top layer. The three sheets are held together with cable ties. This compact solar radiation shield can be suspended, or placed against any flat surface. Care must be taken to ensure that the shield is completely parallel to the ground to prevent direct solar radiation from reaching the sensor, possibly causing increased warm biases in sun-exposed sites in the morning and afternoon relative to the original, larger design. Even so, differences in recorded temperatures between the smaller, compact shield design and the original design were small (mean daytime bias = 0.06 &#176;C). Construction costs are less than half of the original shield design, and the new design results in a less conspicuous instrument that may be advantageous in many field ecology settings.

With the advent of small, low-cost environmental sensors, it is now possible to deploy high-density networks of sensors to measure hyper localized temperature variation. Here, we provide a detailed methodology for constructing a compact version of a previously described custom-fabricated radiation shield for use with inexpensive thermochrons.

Low cost temperature sensors are increasingly used by ecologists to assess climatic variation and change on ecologically relevant scales. Although ...

Construction of a Low-cost Mobile Incubator for Field and Laboratory Use

Incubators are essential for a range of culture-based microbial methods, such as membrane filtration followed by cultivation for assessing drinking water quality. However, commercially available incubators are often costly, difficult to transport, not flexible in terms of volume, and/or poorly adapted to local field conditions where access to electricity is unreliable. The purpose of this study was to develop an adaptable, low-cost and transportable incubator that can be constructed using readily available components. The electronic core of the incubator was first developed. These components were then tested under a range of ambient temperature conditions (3.5 &#176;C - 39 &#176;C) using three types of incubator shells (polystyrene foam box, hard cooler box, and cardboard box covered with a survival blanket). The electronic core showed comparable performance to a standard laboratory incubator in terms of the time required to reach the set temperature, inner temperature stability and spatial dispersion, power consumption, and microbial growth. The incubator set-ups were also effective at moderate and low ambient temperatures (between 3.5 &#176;C and 27 &#176;C), and at high temperatures (39 &#176;C) when the incubator set temperature was higher. This incubator prototype is low-cost (&lt; 300 USD) and adaptable to a variety of materials and volumes. Its demountable structure makes it easy to transport. It can be used in both established laboratories with grid power or in remote settings powered by solar energy or a car battery. It is particularly useful as an equipment option for field laboratories in areas with limited access to resources for water quality monitoring.

This paper describes a method for building an adaptable, low-cost and transportable incubator for microbial testing of drinking water. Our design is based on widely available materials and can operate under a range of field conditions, while still offering the advantages of higher-end laboratory-based models.

Incubators are essential for a range of culture-based microbial methods, such as membrane filtration followed by cultivation for assessing drinking water ...