Funding for this study was provided by U.S. Department of Energy&#39;s Office of Science, Office of Biological and Environmental Research, Terrestrial Ecosystem Sciences Program Award No. DE-SC0007041, Ameriflux Management program under Flux Core Site Agreement No. 7096915 through Lawrence Berkeley National Laboratory, and the National Science Foundation Hydrological Science grant 1521238. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the funding agencies.

1. Select a Tree for Instrumentation
<ol>
	<li>Select trees for measurement. Ideally, select trees that are healthy with a generally round stem cross-section, and a diameter between 1-2 times the tine length, or a sapwood depth greater than the length of the sensor tines (~5 cm for the specific capacitance sensors demonstrated here). Measure the depth of the sapwood using tree cores, or for many species, calculate sapwood depth through allometric equations relating sapwood area to stem diameter 29,54, as measured by a standard diameter tape. 
	NOTE: However, some types of capacitance sensors may be able to be trimmed to an appropriate length following Step 1.2 without adversely affecting measurement accuracy. Only capacitance sensors with rigid measurement tines that do not contain wiring can be trimmed or cut. Separate calibration is necessary for trimmed sensors. Therefore, select the tree and determine the appropriate tine length prior to the calibration procedure.</li>
	<li>Determine the appropriate length of the sensor tines based on the tree&#39;s diameter and sapwood depth. 
	NOTE: Capacitance sensors integrate moisture information over the length of the sensor tines, L. It is therefore assumed that the integrated observation they provide is representative of the entire stem when the diameter is between L and 2L. The bark and phloem will not affect the measurement as they are removed from the measurement area prior to installation (see section 4.2).
	<ol>
		<li>Trim the sensors for trees where L is greater than the stem diameter, (see Step 1.3) such that the tines do not penetrate through the opposite side of the stem.</li>
		<li>Measure the combined signal from the sapwood and heartwood with the sensor for trees where the diameter is larger than 2L, but sapwood depth is less than L. 
		NOTE: As water content differs in these two tissue types, this may cause a bias if it is assumed that the observation is representative of the whole stem. In such cases, or when the user is only interested in the sapwood water fluctuations, the sensor tines must be trimmed to the sapwood depth such that the observations will represent the water content fluctuations of the sapwood (active xylem) only. When the sapwood depth is larger than L, observations represent only the sapwood, but the sensor does not need to be trimmed.</li>
	</ol>
	</li>
	<li>If necessary (as determined in Steps 1.2.1 and 1.2.2), cut the sensor to fit for the specified application. To cut the sensor tines, clamp the sensor securely to a workbench and, while wearing proper protective equipment, use a power rotary tool equipped with a steel cutting disk to cut each tine to precisely the same length.</li>
</ol>
2. Harvest and Prepare Wood Samples of All Species of Interest to Generate a Species-Specific Calibration
<ol>
	<li>Collect a trunk, juvenile stem, or large branch at least 6 cm in diameter from the species of interest. Larger diameters are preferred in order to maximize the amount of wood encasing the sensor and most closely approximate the trunk density for field measurements. Remove all attached branches or leaves, and any lichen or loose material. 
	NOTE: Refer to the Discussion section for further discussion of uncertainty due to differences in branch and stem density.</li>
	<li>Segment the stem into 25 or more cylindrical sections of ~15 cm length.</li>
	<li>Label each segment and record the average diameter and length of each. Approximate the segments&#39; volume as the volume of a cylinder.</li>
	<li>Separate the segments into two groups for differential rehydration and drying. Place roughly 1/3 of the segments in a water bath to rehydrate, and the other 2/3 of the segments in a drying oven at 60 &#176;C to dehydrate. Keep two segments separate for immediate measurement: preferably one from the middle of the length of the stem, and one from an end. 
	NOTE: Typically, segments drying at 60 &#176;C will be fully desiccated after ~2 weeks, and fully rehydrated after ~3 days. Remove individual segments from the oven/water bath and measure daily or twice-daily intervals (see Step 3.7). In order to produce a gradient of measurements spanning the largest range of possible volumetric water contents.</li>
</ol>
3. Create a Calibration Relationship between Sensor Output and Volumetric Water Content
<ol>
	<li>Connect a capacitance sensor to a data logging device, following the instructions provided by the manufacturer, and to a computer for real-time sensor readout visualization. Set the time interval for data collection to 30 s.</li>
	<li>Using a premade drilling template held securely in place to maintain alignment, and a drill bit slightly smaller than the diameter of the tines of the capacitance sensor (3.57 mm for the sensor used in this experiment), drill two vertical sets of three holes with the second set located approximately 150 &#176; away around the wood segment with a vertical separation of a few centimeters to ensure that there is no potential overlap between holes. Use the wood segments set aside in Step 2.4 for the first set of measurements.</li>
	<li>Weigh the segment and record the weight to the nearest 0.01 g at the time of measurement. Cap the ends of the segments with plastic wrap to prevent additional drying.</li>
	<li>Immediately after weighing, clean the tines of the capacitance sensor with an alcohol swab and insert it into the stem segment completely, such that no part of the steel tines is visible. Wait for the measurement reading on the output screen to stabilize (2 or 3 min, generally). Record the sensor outputs of temperature, electrical conductivity, and dielectric permittivity (&#949;b) every 30 s for 5 min and compute the average of the 10 measurements.</li>
	<li>Gently remove the sensor from the segment, clean the tines with an alcohol swab, and wait for the output readings to return to zero. Repeat the measurement procedure from step 3.3 onward in the second set of pre-drilled holes.</li>
	<li>Remove plastic from the ends and place the stem segment in the drying oven. Allow it to desiccate completely (generally 2 weeks, or until weight has stabilized for several days).</li>
	<li>Repeat steps 3.3 through 3.7 for all segments. Remove segments from the drying oven and measure more frequently (twice daily) within the first several days of drying, due to the higher rate of initial moisture loss than during the last several days (daily). Dry excess water from the surface of segments removed from the water bath using a paper towel before weighing and measurement. Measure one rehydrated stem segment per day, until all rehydrated segments have been measured.</li>
	<li>After complete desiccation, record the final dry weight of all stem segments.</li>
	<li>Calculate the volumetric water content (VWC, cm3water /cm3wood) of each stem segment at the time of measurement, using the following formula: 
	<img alt="Equation 1" src="/files/ftp_upload/57062/57062eq1.jpg" /> (1) 
	Where Vw is the volume of water (cm3), and Vstem is the volume of the stem segment (cm3) calculated in step 1.2.
	<ol>
		<li>Calculate the volume of water in each segment at the time of measurement as: 
		<img alt="Equation 2" src="/files/ftp_upload/57062/57062eq2.jpg" /> (2) 
		Where mw is the mass water in the stem segment (g) at the time of measurement, and &#961;w is the density of water (1 g cm-3)</li>
		<li>Calculate the mass of water in each segment at the time of measurement as: 
		<img alt="Equation 3" src="/files/ftp_upload/57062/57062eq3.jpg" /> (3) 
		Where Mwet is the mass of the stem segment at the time of measurement (g), and Mdry is the final weight of the segment (g).</li>
	</ol>
	</li>
	<li>Using a statistical analysis software package, create a best-fit linear regression between sensor-observed dielectric permittivity and VWC (Figure 1, Table 1).</li>
</ol>
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/57062/57062fig1.jpg" /> 
Figure 1: Example calibration curves. Calibration curves generated for Quercus rubra, Acer rubrum, Betula papyrifera, Populus grandidentata, and Pinus strobus following Parts 1 and 2 of this protocol. Equations and coefficients of determination are provided for each in Table 1. <a href="//cloudfront-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/57062/57062fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td></td>
			<td>m</td>
			<td>b</td>
			<td>R2</td>
		</tr>
		<tr>
			<td>B. paprifera</td>
			<td>0.048</td>
			<td>-0.098</td>
			<td>0.967</td>
		</tr>
		<tr>
			<td>A. rubrum</td>
			<td>0.067</td>
			<td>-0.158</td>
			<td>0.853</td>
		</tr>
		<tr>
			<td>Q. rubra (shortened)</td>
			<td>0.120</td>
			<td>0.041</td>
			<td>0.636</td>
		</tr>
		<tr>
			<td>Q. rubra</td>
			<td>0.058</td>
			<td>-0.109</td>
			<td>0.718</td>
		</tr>
		<tr>
			<td>P. grandidentata</td>
			<td>0.023</td>
			<td>-0.028</td>
			<td>0.887</td>
		</tr>
		<tr>
			<td>P. strobus</td>
			<td>0.030</td>
			<td>-0.072</td>
			<td>0.900</td>
		</tr>
	</tbody>
</table>
Table 1: Calibration equations for the conversion of &#949;b to VWC for five temperate tree species. Coefficients &#39;m&#39; and &#39;b&#39; are presented for a linear equation in the standard form: VWC = m*&#949;b+b.
4. Installing Capacitance Sensors in Trees for Field Measurements
<ol>
	<li>Prior to sensor installation, record the stem diameter and the height above the ground surface for each sensor location. Typically, to monitor VWC in the trunk, place one sensor ~0.5 m above the ground surface, and place a second one just below the first major branching split (~7.5 m above the ground, Figure 2).</li>
</ol>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/57062/57062fig2.jpg" /> 
Figure 2: Example field experiment setup. A schematic diagram of sensor locations and orientation in a mature tree adjacent to a data logging station. <a href="//cloudfront-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/57062/57062fig2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<ol start="2">
	<li>Remove the bark to the cambium and create a flat surface where the sensor will be installed using a draw blade. Ensure that this surface is wide and flat enough that the sensor sits flush against the surface of the tree when it is installed such that no part of the tines is exposed. Remove the bark and cambium to ensure that measurements include only water content in the xylem, while excluding water content in the bark or phloem.</li>
	<li>Drill the holes for the tines. Use a drill bit slightly smaller than the diameter of the tines for softer wood, while using a bit closer to the true size of the tines for harder wood (3.57 mm as used in this protocol). For high quality measurements, ensure that the sensor tines make good contact with the wood. Since there will not be a need to remove the sensor regularly, as was the case during the calibration procedure, a slightly smaller drill bit may be used here than the one used for calibration.</li>
	<li>Clean the sensor tines with an alcohol swab to remove any dirt or skin oils, and insert the sensor into the pre-drilled holes. If the sensor meets too much resistance upon insertion, gently back it out and re-drill the holes to widen them slightly. Ensure that all three tines are fully inserted and the body of the sensor sits flush against the tree trunk.</li>
	<li>Use a silicon-based sealant to seal the sensor against the tree trunk to help keep stem flow from entering the holes and to prevent pest infestation.</li>
	<li>Cover the sensor with reflective insulation to avoid external heating.</li>
	<li>Following the manufacturers&#39; specifications, connect all sensors to a 12 V power source and a compatible data logger. Use data collection intervals of 5 min for sensors deployed in the field, but use longer intervals to conserve power in sites where power is limiting, e.g., solar/battery operated sites.</li>
</ol>
5. Process the Raw Data to Stem-Water Storage Using the Calibration Curve
<ol>
	<li>Using the equation of the calibration curve generated in step 2.9, convert the sensor output to VWC for all observations. VWC is generally expressed as cm3 /cm3 or as a percent. The percent VWC will therefore range between 0 and 100%.</li>
	<li>Integrate the total volume of interest (cm3) between the two measurement heights (e.g., in Figure 2: 0.5 m and 7.5 m) by assuming stem diameter changes linearly with height. For trees where the observation represents the whole stem (i.e., trees of diameters between L and 2L, using unmodified sensors, or thinner trees where the sensor was trimmed to the stem diameter, see section 2.2), use equation 4: 
	<img alt="Equation 4" src="/files/ftp_upload/57062/57062eq4.jpg" /> (4) 
	where H is the height difference (vertical distance) between the sensors (e.g., in Figure 2: 700 cm) and r1 and r2 are the radii of the stem (cm) at the bottom and top sensors&#39; locations, respectively. 
	For trees where sensors provide an estimate only of the sapwood water content (see sensor length determination, section 1.2) use eq. 5: 
	<img alt="Equation 5" src="/files/ftp_upload/57062/57062eq5.jpg" /> (5) 
	where s1 and s2 are the sapwood depths (cm) at the bottom and top sensors&#39; locations, respectively.</li>
	<li>Calculate the volume of stem- or sapwood- stored water by multiplying the tree&#39;s average VWC by the total volume of interest.</li>
</ol>

Steven R. Garrity is an employee of METER Group Inc. that produces the GS3 Ruggedized Soil Moisture Sensor used in this Article.

Seasonal and diurnal patterns in stem water content observed via capacitance sensors align with trends in concurrent sap flux and environmental forcing measurements (Figure 3, Figure 4, Figure 5). Reservoirs of stem water storage are depleted diurnally when the pace of transpiration surpasses the rate of recharge through woody tissues, and seasonally when soil moisture limits root-water availability...

Water stored in plant material plays an integral role in plants&#39; ability to cope with short- and long-term water stress1,2. Plants store water in roots, stems, and leaves in both intracellular and extracellular (e.g., xylem vessels) spaces 2,3,4. This water has been shown to contribute between 10 and 50% of diurnally transpired water2,5,6,7,8. As such, plant hydraulic capacitance is a key component of the terrestrial water balance, can be used as an indicator of water stress, drought response, and recovery1, and is a critical factor necessary to correct for observed time lags between transpiration and sap flow9,10,11. Real-time monitoring of vegetation water content can also be used in agricultural applications to help constrain orchard and crop irrigation in order to increase watering efficiency12,13. However, measurements of continuous, in-situ stem-water content of woody species7,14,15,16,17,18,19 are rare relative to sap flux measurements20. Here, we outline a procedure for the calibration of capacitance sensors to monitor the volumetric water content within the stems of trees5,21.
Hydrodynamic behaviors and water-use regulation by vegetation are an integral component of the soil-plant-atmosphere continuum22,23 and are therefore important controls for the water and carbon fluxes between the biosphere and atmosphere24,25. The dynamics of stem water content are influenced by both biotic and abiotic factors. Depletion and recharge of stem-stored water are affected by short- and long-term trends in environmental conditions, in particular, vapor pressure deficit and soil water content1,26. The physical properties of the wood27 (e.g., density, vessel structure) and the emergent hydraulic strategy25 (e.g., iso- or anisohydric stomatal regulation) determine a plant&#39;s ability to store and use water19,26,28, and can vary widely by species29,30. Previous studies have demonstrated different roles of capacitance in tropical16,27,31,32,33 and temperate5,7,21 species, and in both angiosperms1,2,34 and gymnosperms6,11,17,19.
Improved knowledge of biomass water content will improve understanding of vegetation strategies for water acquisition and use1,2, along with species&#39; vulnerability to predicted changes in precipitation regimes35,36. Further understanding of plant water use strategies will help predict shifting demographic patterns under future climate scenarios37,38. Through model-data fusion techniques39, stem water content data obtained using this methodology can be used to inform and test scalable, plant-level hydrodynamics models40,41,42,43,44 in order to improve calculations of stomatal conductance and, thereby, simulations of both transpiration and photosynthetic carbon uptake. These advanced hydrodynamic models may provide a significant reduction in uncertainty and error when incorporated into larger land-surface and Earth systems models25,45,46,47,48.
Methods used to monitor or calculate stem water content include tree coring33,49, electronic dendrometers2,15,50, electrical resistance51, gamma radiation attenuation52, deuterium tracers19, networks of sap flux sensors32,33,53, stem psychrometers49, and amplitude11 and time4,12,13 domain reflectometry (TDR). Recent efforts have tested the viability of capacitance sensors that have traditionally been used to measure soil volumetric water content5,18,21,27. Frequency domain reflectometry (FRD)-style capacitance sensors are low cost and use relatively small amounts of energy for continuous measurements, making them an attractive tool for high temporal resolution measurements in field scenarios. The ease of automation of FDR over TDR-style sensors facilitates the collection of continuous sun-hourly data sets, and eliminates many of the challenges inherent in TDR measurements requiring substantial cable lengths13. The use of in-situ capacitance sensors eliminates the need for repetitive coring or branch harvesting, and may provide enhanced accuracy for hardwood species. Woody species that withdraw water principally from extracellular spaces, such as xylem vessels, or have high wood or bark moduli of elasticity, are generally not good candidates for popular dendrometer measurement techniques due to low elastic stem expansion2. Capacitance sensors estimate dielectric permittivity, which can be directly converted to volumetric water content. However, capacitance measurements are sensitive to the density of the media surrounding the sensor. Therefore, we advocate for species-specific calibrations that convert the output of the sensors to volumetric wood-water content5,21.
We present a protocol for a species-specific calibration to convert capacitance sensor output to volumetric water content of wood. Also provided are instructions for field installation of capacitance sensors in mature trees and a discussion of the method&#39;s strengths, weaknesses, and assumptions. These techniques are designed to monitor volumetric water content in the trunk, the largest tree water storage reservoir8, but can be easily expanded to the whole tree with installation of additional sensors along the branches. Measurements of dynamic plant water content will advance the fields of vegetation hydrodynamics, biometeorology, and land-surface modeling.

<table>
	<tbody>
		<tr>
			<td>Ruggedized Soil Moisture Sensor</td>
			<td>METER Group Inc.</td>
			<td>GS-3</td>
			<td>Capacitance sensors</td>
		</tr>
		<tr>
			<td>1/8&#34; drill bit</td>
			<td>Any</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>9/64&#34; drill bit</td>
			<td>Any</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Drying oven</td>
			<td>Any</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Chainsaw</td>
			<td>Any</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Electric drill</td>
			<td>Any</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Bucket for water bath</td>
			<td>Any</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Alcohol swabs</td>
			<td>Any</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Draw knife</td>
			<td>Any</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Data logger</td>
			<td>Any</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Silicon sealant</td>
			<td>Any</td>
			<td>N/A</td>
			<td></td>
		</tr>
	</tbody>
</table>

the calibration and use of capacitance sensors to monitor stem water content in trees

Water transport and storage through the soil-plant-atmosphere continuum is critical to the terrestrial water cycle, and has become a major research focus area. Biomass capacitance plays an integral role in the avoidance of hydraulic impairment to transpiration. However, high temporal resolution measurements of dynamic changes in the hydraulic capacitance of large trees are rare. Here, we present procedures for the calibration and use of capacitance sensors, typically used to monitor soil water content, to measure the volumetric water content in trees in the field. Frequency domain reflectometry-style observations are sensitive to the density of the media being studied. Therefore, it is necessary to perform species-specific calibrations to convert from the sensor-reported values of dielectric permittivity to volumetric water content. Calibration is performed on a harvested branch or stem cut into segments that are dried or re-hydrated to produce a full range of water contents used to generate a best-fit regression with sensor observations. Sensors are inserted into calibration segments or installed in trees after pre-drilling holes to a tolerance fit using a fabricated template to ensure proper drill alignment. Special care is taken to ensure that sensor tines make good contact with the surrounding media, while allowing them to be inserted without excessive force. Volumetric water content dynamics observed via the presented methodology align with sap flow measurements recorded using thermal dissipation techniques and environmental forcing data. Biomass water content data can be used to observe the onset of water stress, drought response and recovery, and has the potential to be applied to the calibration and evaluation of new plant-level hydrodynamics models, as well as to the partitioning of remotely sensed moisture products into above- and belowground components.

In this section, we present calibration data for five common eastern forest tree species, followed by a detailed analysis of field measurements of stem-water storage in three Acer rubrum individuals during the 2016 growing season. Calibration curves were generated for Acer rubrum, Betula papyrifera, Pinus strobus, Populus grandidentata, and Quercus rubra (Figure 1). Slopes of the curves differed by as much as 97.7% for P. grandi...

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The Calibration and Use of Capacitance Sensors to Monitor Stem Water Content in Trees

The hydraulic capacitance of biomass is a key component of the vegetation water budget, which serves as a buffer against short and long-term drought stresses. Here, we present a protocol for the calibration and use of soil moisture capacitance sensors to monitor water content in the stems of large trees.

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12.4K Views.  University of Texas at Austin. The hydraulic capacitance of biomass is a key component of the vegetation water budget, which serves as a buffer against short and long-term drought stresses. Here, we present a protocol for the calibration and use of soil moisture capacitance sensors to monitor water content in the stems of large trees.

Video: The Calibration and Use of Capacitance Sensors to Monitor Stem Water Content in Trees

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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.

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

Methods of Soil Resampling to Monitor Changes in the Chemical Concentrations of Forest Soils

Recent soils research has shown that important chemical soil characteristics can change in less than a decade, often the result of broad environmental changes. Repeated sampling to monitor these changes in forest soils is a relatively new practice that is not well documented in the literature and has only recently been broadly embraced by the scientific community. The objective of this protocol is therefore to synthesize the latest information on methods of soil resampling in a format that can be used to design and implement a soil monitoring program. Successful monitoring of forest soils requires that a study unit be defined within an area of forested land that can be characterized with replicate sampling locations. A resampling interval of 5 years is recommended, but if monitoring is done to evaluate a specific environmental driver, the rate of change expected in that driver should be taken into consideration. Here, we show that the sampling of the profile can be done by horizon where boundaries can be clearly identified and horizons are sufficiently thick to remove soil without contamination from horizons above or below. Otherwise, sampling can be done by depth interval. Archiving of sample for future reanalysis is a key step in avoiding analytical bias and providing the opportunity for additional analyses as new questions arise.

Repeated soil sampling has recently been shown to be an effective way to monitor forest soil change over years and decades. To support its use, a protocol is presented that synthesizes the latest information on soil resampling methods to aid in the design and implementation of successful soil monitoring programs.

Recent soils research has shown that important chemical soil characteristics can change in less than a decade, often the result of broad environmental ...

Controlled-release of Chlorine Dioxide in a Perforated Packaging System to Extend the Storage Life and Improve the Safety of Grape Tomatoes

A controlled-release chlorine dioxide (ClO2) pouch was developed by sealing a slurry form of ClO2 into semipermeable polymer film; the release properties of the pouch were monitored in containers with or without fruit. The pouch was affixed to the inside of a perforated clamshell containing grape tomatoes, and the effect on microbial population, firmness, and weight loss was evaluated during a 14 day storage period at 20 &#176;C. Within 3 days, the ClO2 concentration in the clamshells reached 3.5 ppm and remained constant until day 10. Thereafter, it decreased to 2 ppm by day 14. The ClO2 pouch exhibited strong antimicrobial activity, reducing Escherichia coli populations by 3.08 log CFU/g and Alternaria alternata populations by 2.85 log CFU/g after 14 days of storage. The ClO2 treatment also reduced softening and weight loss and extended the overall shelf life of the tomatoes. Our results suggest that ClO2 treatment is useful for extending the shelf life and improving the microbial safety of tomatoes during storage without impairing their quality.

Here, we describe a protocol for the application of a novel, slow-release ClO2 product that reduces spoilage and extends the shelf life of fresh fruit. The slow-release ClO2 product was added to standard commercial grape tomato packaging and tested against Escherichia coli and Alternaria alternata.

A controlled-release chlorine dioxide (ClO2) pouch was developed by sealing a slurry form of ClO2 into semipermeable polymer film; the release properties ...

A Simple Planting Technique for Re-establishing Trees Where Frequent Inundation Occurs

Many of the Everglades tree islands have lost elevation over the past century and most of their trees have died such that they are now covered with herbaceous plants. This protocol describes a simple, cost-effective tree planting technique needed for restoring degraded Everglade tree islands. The design is patterned after a natural Everglades process that creates floating peat islands, which allows tree survival and growth in flooded conditions and often leads to the development of tree islands. Commercially available peat bags were used as the medium for the growth and establishment of potted native tree saplings. The pop-up configuration floated initially and provided additional elevation to minimize inundation, with a single native tree species sapling and a single tree fertilizer spike. During a 3 year study involving 105 pop-ups, most plants survived (80%) and many thrived. Determining whether this technique can establish trees on a degraded tree island will require longer studies and extensive field tests.

This protocol describes a simple, cost-effective tree planting technique for restoring degraded Everglades tree islands that experience inundation. The design creates an island (pop-up) which floats initially and adds elevation to promote tree survival and growth under flooded conditions.

Many of the Everglades tree islands have lost elevation over the past century and most of their trees have died such that they are now covered with ...

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 ...

BtM, a Low-cost Open-source Datalogger to Estimate the Water Content of Nonvascular Cryptogams

Communities of nonvascular cryptogams, such as mosses or lichens, are an important part of the Earth's biodiversity, contributing to the regulation of the carbon and nitrogen cycles in many ecosystems. Being poikilohydric organisms, they do not actively control their internal water content and need a humid environment to activate their metabolism. Therefore, studying water relationships of nonvascular cryptogams is crucial to understand both their diversity patterns and their functions in the ecosystems. We present the BtM datalogger, a low-cost open-source platform for the study of the water content of nonvascular cryptogams. The datalogger is designed to measure ambient temperature, humidity, and conductance from up to eight samples simultaneously. We provide a design for a printed circuit board (PCB), a detailed protocol to assemble the components, and the required source code. All this makes the assembly of the BtM datalogger accessible to any research group, even to those without previous specialized knowledge. Therefore, the design presented here has the potential to help popularize the use of this type of device among ecologists and field biologists.

We present a simple and cost-effective method to build an open-source datalogger that measures the conductance of nonvascular cryptogams together with the environmental temperature and humidity. We describe the hardware design of the datalogger and provide step-by-step assembly instructions, the list of required open-source logging software, the code to run the datalogger, and a calibration protocol.

Communities of nonvascular cryptogams, such as mosses or lichens, are an important part of the Earth's biodiversity, contributing to the regulation of the ...

Composition and Distribution Analysis of Bioaerosols Under Different Environmental Conditions

Variable microorganisms in particulate matter (PM) under different environmental conditions may have significant impacts on human health. In this study, we described a protocol for multiple analyses of the biological compositions in environmental PM. Five experiments are presented: (1) PM number monitoring by using a laser particle counter; (2) PM collection by using a cyclonic aerosol sampler; (3) PM collection by using a high-volume air sampler with filters; (4) culturable microbes collection by the Andersen six-stage sampler; and (5) detection of biological composition of environmental PM by bacterial 16SrDNA and fungal ITS region sequencing. We selected hazy days and a livestock farm as two typical examples of the application in this protocol. In this study, these two sampling methods, cyclonic aerosol sampler and filter sampler, showed different sampling efficiency. The cyclonic aerosol sampler performed much better in terms of collecting bacteria, while these two methods showed the same efficiency in collecting fungi. Filter samplers can work under low temperature conditions while cyclonic aerosol samplers have a sampling limitation for temperature. A solid impacting sampler, such as an Andersen six-stage sampler, can be used to sample bioaerosols directly into the culture medium, which increases the survival rate of culturable microorganisms. However, this method mainly relies on culture while more than 99% of microbes cannot be cultured. DNA extracted from the culturable bacteria collected by the Andersen six-stage sampler and samples collected by cyclonic aerosol sampler and filter sampler were detected by bacterial 16S rDNA and fungal ITS region sequencing.All the methods above may have wide application in many fields of study, such as environmental monitoring and airborne pathogen detection. From these results, we can conclude that these methods can be used under different conditions and may help other researchers further explore the health impacts of environmental bioaerosols.

Understanding the biological composition of environmental particulate matter is important for the study of its significant impacts on human health and disease spread. Here, we used three types of bioaerosol sampling methods and a biological analysis of airborne microbes to better explore airborne microbial communities under different environmental conditions.

Variable microorganisms in particulate matter (PM) under different environmental conditions may have significant impacts on human health. In this study, ...