Name: integrated field lysimetry and porewater sampling for evaluation of chemical mobility in soils and established vegetation
Uploaded: 2014-07-04T15:00:00
Description: Watch this Scientific Journal Video about Integrated Field Lysimetry and Porewater Sampling for Evaluation of Chemical Mobility in Soils and Established Vegetation at JoVE.com

The authors acknowledge the staff at the NCDA Sandhills Research Station for assistance with lysimeter installation and exhumation. Funding for experiments described in Representative Results was provided by the Center for Turfgrass Environmental Research &#38; Education. Video and manuscript production was supported by the North Carolina State University Departments of Soil Science and Crop Science.

Field sampling is performed in this experiment and is under the authorization of the North Carolina Department of Agriculture &#38; Consumer Services.
1. Field Lysimeter Installation
<ol>
	<li>Choose an experimental site on which lateral movement of applied chemicals is unlikely (i.e. sites with little or no slope). Select sites based on soil and vegetation properties of interest.</li>
	<li>If plots are vegetated, pull vegetation plugs prior to lysimeter installation (Figure...

<ol>
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C., Georgiadis, M., Jayachandran, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessment+of+arsenic+mobility+in+the+soils+of+some+golf+courses+in+South+Florida.">Assessment of arsenic mobility in the soils of some golf courses in South Florida.</a> Science of the Total Environment. 291, 123-134 (2002).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Water+quality,+pesticide+occurrence,+and+effects+of+irrigation+with+reclaimed+water+at+golf+courses+in+Florida.">Water quality, pesticide occurrence, and effects of irrigation with reclaimed water at golf courses in Florida.</a> Swancar, A. (ed USGS) Tallahassee. , (1996).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Organic+arsenical+herbicides+(MSMA,+DSMA,+CAMA,+and+Cacodylic+Acid),+reregistration+eligibility+decision;+notice+of+availability.">Organic arsenical herbicides (MSMA, DSMA, CAMA, and Cacodylic Acid), reregistration eligibility decision; notice of availability.</a> Environmental Protection Agency, Federal Register Environmental Documents. , 1-70 (2006).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=EPA+(not+Araujo+as+stated+before)+Organic+Arsenicals;+Amendments+to+Terminate+Uses:+Amendment+to+Existing+Stocks+Provision.">EPA (not Araujo as stated before) Organic Arsenicals; Amendments to Terminate Uses: Amendment to Existing Stocks Provision.</a> Environmental Protection Agency) 18590-18591 Federal Registrar. 78, (2013).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drinking+Water+Regulations;+Arsenic+and+Clarifications+to+Compliance+and+New+Source+Contaminants+Monitoring+Final+Rule.">Drinking Water Regulations; Arsenic and Clarifications to Compliance and New Source Contaminants Monitoring Final Rule.</a> Environmental Protection Agency. 66, (2001).</li><li>Winton, K., Weber, J. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+review+of+field+lysimeter+studies+to+describe+the+environmental+fate+of+pesticides.">A review of field lysimeter studies to describe the environmental fate of pesticides.</a> Weed Technology. 10, 202-209 (1996).</li><li>Bergstr&#246;m, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+lysimeters+to+estimate+leaching+of+pesticides+in+agricultural+soils.">Use of lysimeters to estimate leaching of pesticides in agricultural soils.</a> Environmental Pollution. 67, 325-347 (1990).</li><li>Byron, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lysimeters+promoted+for+pesticide+research.">Lysimeters promoted for pesticide research.</a> Environmental Science and Technology. 31, (1997).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Infographic:+Pesticide+Planet.">Infographic: Pesticide Planet.</a> Science. 341, 730-731 (2013).</li><li>Severson, R., Grigal, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Soil+solution+concentrations:+effects+of+extraction+time+using+porous+ceramic+cups+under+constant+tension.">Soil solution concentrations: effects of extraction time using porous ceramic cups under constant tension.</a> Water Resources Bulletin. 12, 1161-1170 (1976).</li><li>Allaire, S. E., Roulier, S., Cessna, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantifying+preferential+flow+in+soils:+A+review+of+different+techniques.">Quantifying preferential flow in soils: A review of different techniques.</a> Journal of Hydrology. 378, 179-204 (2009).</li><li>Weiherm&#252;ller, L., Kasteel, R., Vanderborght, J., P&#252;z, T., Vereecken, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Soil+Water+Extraction+with+a+Suction+Cup.">Soil Water Extraction with a Suction Cup.</a> Valdose Zone Journal. 4, 899-907 (2005).</li><li>Jury, W. A., Fluhler, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Advances in Agronomy. 47, 141-201 (1992).</li></ol>

Utilizing an integrated field lysimetry and porewater sampling approach allows researchers to assess spatial and temporal distributions of a wide variety of land-applied chemicals. The fate of chemicals in soils and vegetated systems may be controlled by a number of environmental processes and attributes, such as downward leaching, volatilization, hydrolysis, photolysis, microbial transformation/degradation, plant uptake, soil type, and soil pH16,17. Unlike greenhouse or laboratory-based experiments, results f...

Potentially toxic chemicals are routinely applied to land from sources such as pesticides, fertilizers, sewage/biosolids, industrial wastes, and municipal wastes1,2. The fate of these chemicals &#8211; which may include nutrients, trace elements, organics, and their associated metabolites &#8211; is often not well understood3. If the chemicals are not managed properly, they have the potential to threaten human and environmental health through their transfer to and buildup in plants, surface water, and groundwater. With a global population that may reach 10 billion people by 2050, there are growing demands on waste management and food production2, and land application of many chemicals has been increasing3,4. Accordingly, research is needed that quantifies the transformations, mobility, loading limits, and overall environmental risks from chemicals that require land disposal or that we depend upon to enhance crop health and yield.
A number of strategies have been employed to evaluate threats from chemicals applied in the environment. Laboratory-based, model-system studies have been conducted to provide information about fundamental mechanisms controlling the mobility of chemicals in soils. When analyzing chemical fate in a laboratory, complete manipulation of the &#8220;environment&#8221; and inputs may be achieved, but these rarely match real-world environmental conditions5,6. Thus, extrapolating lab results to field settings may lead to inaccurate predictions about chemical threats. In contrast, broad field measurements have been used to define chemical behavior in the environment. However, conclusions about environmental fate from these measurements are often complicated due to the frequently low use rates (e.g. a few g A-1) of applied chemicals, as well as the complex interactions between hydrological and biogeochemical processes in the environment that regulate chemical distributions.
Lysimetry, including field lysimetry, has historically been used by soil and crop scientists to systematically evaluate the downward mobility of chemicals applied to soils and established vegetation. A lysimeter is a device made of metal or plastic that is placed into a soil of interest and is used to determine the fate of chemicals applied in known amounts to a confined area. Soil and vegetation samples collected from lysimeters can be used to assess the evolution of chemical distributions over time. Because field lysimetry is carried out under natural environmental conditions, results may be used to predict real-case scenarios derived from chemical applications to soil systems. Early lysimeter studies measured transpiration, moisture flow, and/or nutrient movement. Modern-day lysimeter studies measure pesticide and nutrient dissipation, pesticide movement, volatility, and mass balance, along with the aforementioned measurements3.
A limitation of traditional field lysimetry is that chemical mobility within a soil profile is largely defined by solid-phase measurements, while less attention is paid to dissolved chemical concentrations in water percolating through the soils &#8211; a critical component that may impact the potential for groundwater contamination from land-applied chemicals. Although leachate from the bottom of the lysimeters is sometimes collected for analysis, this approach limits depth resolution of porewater concentrations and typically requires significant soil excavation prior to experimentation. Instead, to obtain data about chemical concentrations in soil water, porewater samplers may be utilized in field settings. Porewater samplers are installed in soils to collect water from discrete, desired depths and only minimally disturb the soil system. Porewater samplers have been referred to by many names including lysimeters, suction cup lysimeters, or soil solution samplers, convoluting their distinction with the traditional field lysimeters described above. In this paper, we will use the term &#8220;porewater sampler&#8221; to alleviate confusion.
Here, we demonstrate an experimental approach that combines field lysimetry and porewater sampling for evaluating the downward leaching potential of chemicals applied to vegetated soil or bareground systems. Lysimetry has been a powerful tool used since the 1700s7, while ceramic porewater sampling has been used since the early 1960s8. Integration of these robust techniques allows for field determination of both solid- and dissolved-phase chemical concentration distributions while minimizing soil disturbance. This paper describes factors to consider when designing an experiment, including site selection, device installation, and sample collection. The approach is illustrated with an experiment that evaluated the fate of an organic arsenical pesticide applied to a bareground and an established turfgrass system. The techniques described can be adjusted as necessary to examine the fate of a wide variety of chemicals, thereby providing invaluable tools to researchers and policy-makers who seek to understand the environmental fate and behavior of land-applied chemicals.

<table border="0" cellpadding="0" cellspacing="0" width="1187">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:244px;">Name of Material/ Equipment</td>
			<td style="width:168px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td style="width:656px;">Comments/Description</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:244px;">Prenart Super Quartz Samplers (PFTE/Quartz)</td>
			<td style="width:168px;">Prenart Equipment ApS</td>
			<td style="width:119px;">N/A</td>
			<td>Any samplers for&#160; trace metal analysis can be used (e.g. SoilMoisture Equipment Corp.)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:244px;">Prenart Installation Kit</td>
			<td style="width:168px;">Prenart Equipment ApS</td>
			<td style="width:119px;">N/A</td>
			<td>Contains all items necessary to install porewater samplers</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:244px;">2 L collecting bottles</td>
			<td style="width:168px;">Prenart Equipment ApS</td>
			<td></td>
			<td style="width:656px;">Bottles can also be purchased from Fisher Scientific (02-923-2) or other laboratory supply companies, but fittings will need to be adjusted. Bottles can be covered with dark material if light sensitive</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:244px;">Portable vacuum pump</td>
			<td style="width:168px;">Prenart Equipment ApS</td>
			<td style="width:119px;">N/A</td>
			<td>Vacuporter from Decagon Devices or other field battery-operated or hand vacuum pump may be used</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:244px;">1 oz HDPE Nalgene Bottles</td>
			<td style="width:168px;">Fisher Scientific</td>
			<td style="width:119px;">03-313-4A</td>
			<td>Sample bottle type will depend on analyte of interest and may be glass</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:244px;">Concentrated nitric acid</td>
			<td style="width:168px;">Fisher Scientific</td>
			<td style="width:119px;">A509-P212</td>
			<td>Oxidizing and corrosive-other acids may be needed for preservation and should be used with caution</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:244px;">25 mm 0.2 &#181;m nylon syringe filters</td>
			<td style="width:168px;">VWR</td>
			<td style="width:119px;">28145-487</td>
			<td>Other filter types and pore sizes may be used, dependent on the analyte of interest and analytical instrumentation</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:244px;">60 mL Luer-Lok syringes</td>
			<td style="width:168px;">Fisher Scientific</td>
			<td style="width:119px;">13-689-8</td>
			<td>Other sizes may be used depending on sample volume collected</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:244px;">Portable pH meter</td>
			<td style="width:168px;">VWR</td>
			<td style="width:119px;">248481-A01</td>
			<td>Other pH meters can be used following calibration</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:244px;">Graduated Cylinder</td>
			<td style="width:168px;">any</td>
			<td style="width:119px;">N/A</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:244px;">Field lysimeters (metal, plastic, etc.)</td>
			<td style="width:168px;">N/A</td>
			<td style="width:119px;">N/A</td>
			<td>Often these are constructed based on the researchers specifications</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:244px;">Inverted Post Driver Tractor</td>
			<td style="width:168px;">N/A</td>
			<td style="width:119px;">N/A</td>
			<td>Any tractor can be used to install the lysimeters</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:244px;">Handheld Boom Sprayer</td>
			<td style="width:168px;">N/A</td>
			<td style="width:119px;">N/A</td>
			<td>To apply the rate needed for application&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:244px;">Polyethylene bags</td>
			<td style="width:168px;">Johnson &#38; Johnson</td>
			<td style="width:119px;">N/A</td>
			<td>Other brands may be used for soil storage</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:244px;">Reciprocating saw</td>
			<td style="width:168px;">Black &#38; Decker&#160;</td>
			<td style="width:119px;">N/A</td>
			<td>Any reciprocating saw can be used with a metal cutting attachment</td>
		</tr>
	</tbody>
</table>

integrated field lysimetry and porewater sampling for evaluation of chemical mobility in soils and established vegetation

Potentially toxic chemicals are routinely applied to land to meet growing demands on waste management and food production, but the fate of these chemicals is often not well understood. Here we demonstrate an integrated field lysimetry and porewater sampling method for evaluating the mobility of chemicals applied to soils and established vegetation. Lysimeters, open columns made of metal or plastic, are driven into bareground or vegetated soils. Porewater samplers, which are commercially available and use vacuum to collect percolating soil water, are installed at predetermined depths within the lysimeters. At prearranged times following chemical application to experimental plots, porewater is collected, and lysimeters, containing soil and vegetation, are exhumed. By analyzing chemical concentrations in the lysimeter soil, vegetation, and porewater, downward leaching rates, soil retention capacities, and plant uptake for the chemical of interest may be quantified. Because field lysimetry and porewater sampling are conducted under natural environmental conditions and with minimal soil disturbance, derived results project real-case scenarios and provide valuable information for chemical management. As chemicals are increasingly applied to land worldwide, the described techniques may be utilized to determine whether applied chemicals pose adverse effects to human health or the environment.

This method allows for the accumulation of data on the fate of chemicals applied to bareground and vegetated soil systems5,10. This approach was used to evaluate arsenic (As) downward leaching, absorption, and translocation into plants for bermudagrass (Cynodon dactylon) systems following application of the organic arsenical herbicide monosodium methyl arsenate (MSMA)9. Since the 1960s, MSMA has been used in non-cropland, turfgrass, and cotton production, but there is growing concern that a...

Watch this Scientific Journal Video about Integrated Field Lysimetry and Porewater Sampling for Evaluation of Chemical Mobility in Soils and Established Vegetation at JoVE.com

Integrated Field Lysimetry and Porewater Sampling for Evaluation of Chemical Mobility in Soils and Established Vegetation

Field lysimetry and porewater sampling allow researchers to evaluate the fate of chemicals applied to soils and established vegetation. The goal of this protocol is to demonstrate how to install required instrumentation and collect samples for chemical analysis during integrated field lysimetry and porewater sampling experiments.

Potentially toxic chemicals are routinely applied to land to meet growing demands on waste management and food production, but the fate of these chemicals ...

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