We wish to thank Pablo Vital and Johnny Mosley for help with field sampling, and Viviana Nadal and Irina Ognevich for help with laboratory analyses.

1. Datalogger Installation and Workings
<ol>
	<li>Identify a study farm and install a datalogger that triggers an autosampler to collect composite flow samples on a flow proportional basis, which requires monitoring canal levels, pump head revolutions, and pump calibration equation.</li>
</ol>
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/56088/56088fig1.jpg" /> 
Figure 1: ISCO sampler used to program auto-sampling procedures for the composite drainage water and the particulates water sampling. <a href="//cloudfront.jove.com/files/ftp_upload/56088/56088fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<ol start="3">
	<li>Monitor the farm canal levels using pressure transducers installed in the inflow and outflow canals adjacent to the pump station.</li>
	<li>Monitor pump speed using proximity switches that are installed on the pump heads; speed is recorded by the datalogger in revolutions per minute (rpm). 
	NOTE: Proximity switches are pieces of metal which when passed over each other count the number of rpms. They are welded onto the pump heads.</li>
	<li>Measure rainfall using a tipping bucket rain gauge that is connected to the datalogger. 
	NOTE: The datalogger communicates by radio telemetry to a base radio station located at UF/IFAS Everglades Research and Education Center. Telemetry is not necessary for controlling sample collection, only for data collection and storage.</li>
</ol>
2. Drainage Flow-weighted Water Sampling
<ol>
	<li>Calculate drainage flow using a datalogger and a pump calibration equation for each pump. Drainage flow-weighted sampling is achieved by an autosampler that is actuated by the datalogger after a trigger drainage volume is achieved. 
	NOTE: The pump speed and flow rates vary over 24 h. The ISCO sampling is triggered by the volume of water discharged, not the rate. The autosampler is programmed to collect a sub-sample after a fixed volume of water discharge. The volume of water discharge is calibrated based on the number of pump rpms.</li>
	<li>Collect a composite water sample (minimum 500 mL) using an in situ automated sampler located at the pump station and program it to capture a daily composite water sample during drainage events. 
	NOTE: The ISCO sampler is plumed to the collection tanks using tubing diverted through a datalogger that takes a 2 L sample every 2 min up to 400 L.</li>
	<li>Program sample trigger volumes to allow for a maximum of 30 samples per 24 h discharge period.
	<ol>
		<li>Program the datalogger to collect composite flow samples by following these steps: Enter Program &#8594; Program &#8594; Flow Based Sampling &#8594; Sample every 1 Pulses &#8594; 30 Composite Samples &#8594; Sample Volume of 130 mL &#8594; Calibrate Sample Volume [NO] &#8594; Enter Start Time [NO] &#8594; Program Sequence Complete.</li>
	</ol>
	</li>
	<li>Store the flow-weighted composite samples in an onsite refrigerator at 4 &#176;C until collection and transportation back to the laboratory for analyses in an ice-filled cooler.</li>
	<li>Analyze the water samples for soluble reactive P within 24 h from the time of sample collection. Samples used for Total P (TP) analysis can be acidified and stored at 4 &#176;C for up to 28 days15.</li>
</ol>
3. Capturing Suspended Particulates
<ol>
	<li>Place a series of two 200 L PVC settling tanks to collect farm canal discharge water over the duration of the drainage period to capture and characterize the suspended particulates.
	<ol>
		<li>Program the datalogger to collect suspended particulates samples by following these steps: Program &#8594; Time Based Sampling &#8594; Sample every 2 min &#8594; Composite Samples [200] &#8594; Calibrate Sample Volume [NO] &#8594; Enter Start Time [NO] &#8594; Sequence Complete &#8594; Push Sampling Button.</li>
	</ol>
	</li>
	<li>Collect flow-weighted drainage water in the setting tanks (2 L every 2 min) based on the volume of water over a 24 h collection period.</li>
</ol>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/56088/56088fig2.jpg" /> 
Figure 2: Two 200 L tanks used to collect drainage water. Suspended particulates settle out at the bottom of the tank and are transferred in five-gallon buckets. <a href="//cloudfront.jove.com/files/ftp_upload/56088/56088fig2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<ol start="3">
	<li>Siphon off the excess water using hoses as particulates start to settle in the tanks.</li>
	<li>Transfer the particulates into five-gallon buckets, transport them back to laboratory, and place them in a refrigerator at 4 &#176;C.</li>
	<li>Siphon off the excess water after settling for 24 h, and transfer the particulates into Imhoff settling cones.</li>
	<li>After settling for at least 1 h, siphon off the excess water one last time before settled particulates are transferred into pre-weighed 500 mL screw-top jars for storage at 4 &#176;C.</li>
	<li>Weigh jars with particulate samples.</li>
	<li>Proceed with phosphorus fractionation analyses as described by Hedley and Stewart14.</li>
</ol>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/56088/56088fig3.jpg" /> 
Figure 3: Imhoff settling cones used to collect the suspended particulates captured in the settling tank. <a href="//cloudfront.jove.com/files/ftp_upload/56088/56088fig3large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

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	<li>Sims, J. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phosphorus+loss+in+agricultural+drainage:+historical+perspective+and+current+research.">Phosphorus loss in agricultural drainage: historical perspective and current research.</a> J. Environ. Qual. 27, 277-293 (1997).</li><li>Van Esbroeck, C. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Surface+and+subsurface+phosphorus+export+from+agricultural+fields+during+peak+flow+events+over+the+non-growing+season+in+regions+with+cool,+temperate+climates.">Surface and subsurface phosphorus export from agricultural fields during peak flow events over the non-growing season in regions with cool, temperate climates.</a> J. Soil Water Conserv. 72, 65-76 (2017).</li><li>Bhadha, J. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phosphorus+mass+balance+and+internal+load+in+an+impacted+subtropical+isolated+wetland.">Phosphorus mass balance and internal load in an impacted subtropical isolated wetland.</a> Water Air Soil Pollut. 218, 619-632 (2011).</li><li>Eyre, B. D., McConchie, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+implications+of+sedimentological+studies+for+environmental+pollution+assessment+and+management:+Examples+from+fluvial+system+in+north+Queensland+and+western+Australia.">The implications of sedimentological studies for environmental pollution assessment and management: Examples from fluvial system in north Queensland and western Australia.</a> Sediment. Geol. 85, 235-252 (1993).</li><li>Bhadha, J. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Soil+phosphorus+release+and+storage+capacity+from+an+impacted+subtropical+wetland.">Soil phosphorus release and storage capacity from an impacted subtropical wetland.</a> Soil Sci. Soc. Amer. J. , 74 (2010).</li><li>Kenney, W. F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Whole-basin,+mass-balance+approach+for+identifying+critical+phosphorus-loading+thresholds+in+shallow+lakes.">Whole-basin, mass-balance approach for identifying critical phosphorus-loading thresholds in shallow lakes.</a> Journal of Paleolim. 51, 515-528 (2014).</li><li>Freebairn, D. N., Wockner, G. 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There are no disclosures associated with this study.

The autosamplers for drainage water particulate collection were placed near the exiting pump station dataloggers. Power was supplied by 12 V batteries that are charged by solar panels. The autosamplers were controlled by the on-site dataloggers, which turned the autosamplers on when the exit pumps ran, and turned them off when pumping stopped. Openings of the sampler intake lines were positioned 0.5 m above the canal bottom and upflow from the pump station. The intake lines were held in place by installing a metal rebar ...

The fate and transport of suspended particulates has been the subject of numerous studies due to its role in eutrophication, particularly in agricultural systems1,2. A comprehensive evaluation of nutrients contained in particulate matter within an aquatic system is necessary to investigate numerous environmental issues such as, the internal cycling of nutrients and release to the overlying water column3, substrate stability, light availability within the water column, and eventually water quality concerns to downstream ecosystems4. The quantity of phosphorus (P) stored in the particulate form (organic matter or sediments) is typically greater than in the water column5. A study conducted by Kenney et al.6 showed that recent sediments that were deposited in Lake Lochloosa, Florida were between the age range of 1900 and 2006. These younger sediments contained nearly 55 times more P than that which was present in the water column. One approach to characterize the potential impact that particulates may have on a particular system is to conduct a quantitative inventory of phosphorus stored in sediment discharged during drainage events. Collection and analysis of these discharged particulates can help estimate downstream nutrient enrichment impacts on sensitive ecosystems.
Storm events typically represent a small fraction of time, yet may contribute the majority of P load discharge in farm drainage. This is because in order to prevent fields from flooding, a large volume of water is drained over short periods of time. Rainfall intensity and flow rates are vital driving factors that can control the concentration of suspended sediments in overland runoff7. Designing monitoring methods that captures flow-weighted composite water samples would help avoid errors associated with complex, high intensity rain events. During high discharge events like storms, the quick and drastic changes in concentrations may not be representative of the average pollutant concentration for the incremental volume. Therefore, flow-weighted water samples far more accurately represents the concentration of a discharge event as it is a summation of loads over a period of time8. The most common flow-weighted samples are automatically collected discrete or composite samples. By capturing the exported suspended particulates from farm drainage during discharge allows us to quantify the severity of the event on P loading. The method described in this study helps capture the particulates that can later be characterized for various physical and chemical properties. The novelty of sampling drainage discharge using a continuous composite flow method versus grab sampling is that it is a better representation of field conditions over the entire duration of the drainage event. Whereas, grab sampling is a &#8220;snapshot&#8221; in time and may not fully represent the effect of the entire event.
The Everglades Agricultural Area (EAA) in South Florida, USA is a large expanse of the original Everglades that was channelized and drained for farming, commercial, and residential development. Nearly 1,100 million m3 of water is discharged annually from and through the EAA to the south and southeast9. Soils in the EAA are Histosols that commonly contain over 85% organic matter by weight and have less than 35% mineral content10. Canal sediments typically have low bulk density (between 0.14 g cm-3 to 0.35 g cm-3), high organic matter content (between 31 - 35%) and Total P (TP) values ranging between 726 -1,089 mg kg-1 11.
For the purpose of this demonstration, a farm within the EAA was selected. The hydroscape of how water flows within the EAA depends on pumps and gravity. Each farm in the EAA comprises on at least one main canal, and multiple field ditches. The field ditches run perpendicular to the main canal. The pumps typically serve a dual purpose; they deliver irrigation water to the farm, and also discharge drainage water off-site. When the fields need to be drained, water in the main canal is lowered, and water from the field drains into the ditches, driven by a hydraulic gradient. Due to only a slight slope in surface most of the rainfall that occurs on the fields flows through the soil profile in transit to the field ditches.&#160; During irrigation, the system is reversed. There is no network of tile drainage in the EAA. The water table is maintained at a specific height due to a confining layer of limestone bedrock underling the soils.&#160; Water is brought in through the main canals; field ditches are filled, and water is allowed to seep into the soil profile to raise the water table levels in the fields. Typically, demands for irrigation water in the EAA occur during March, April, and May (dry season), with very little drainage discharge. In contrast, the volume of water being discharged between June and October (wet season) is significantly higher. The presence of canal bank berms and ditches allows for minimal surface runoff as a potential source of P loading into farm canals12.
In this visual experiment, we present a novel method of capturing flow-weighted suspended particulates during drainage events that can later be used for physico-chemical characterization such as bulk density, organic matter content, and P fractionation13,14.

<table><tbody><tr><td>Datalogger</td><td>Campbell Scientific</td><td></td><td>model CR1000</td></tr><tr><td>Auto-sampler</td><td>ISCO</td><td></td><td>model 3700</td></tr><tr><td>Pressure transducer</td><td>KPSI</td><td></td><td>model 700</td></tr><tr><td>Tipping bucket rain guage</td><td>Texas Electronics</td><td></td><td>model TR-525</td></tr><tr><td>Potassium Chloride</td><td>Fisher</td><td>7447-40-7</td><td></td></tr><tr><td>Sodium Hydroxide</td><td>Fisher</td><td>1310-73-2</td><td></td></tr><tr><td>Hydrochloric Acid</td><td>Fisher</td><td>7647-01-0</td><td></td></tr><tr><td>Sulfuric Acid</td><td>Fisher</td><td>7664-93-9</td><td></td></tr><tr><td>Potassium Persulfate</td><td>Fisher</td><td>7727-21-1</td><td></td></tr><tr><td>Ammonium Molybdate Tetrahydrate</td><td>Fisher</td><td>12054-85-2</td><td></td></tr><tr><td>L-Ascorbic Acid</td><td>Fisher</td><td>50-81-7</td><td></td></tr><tr><td>100 mg/L Anhydrous Phosphate Standard</td><td>ERA</td><td>061</td><td></td></tr><tr><td>Antimony Potassium Tartrate Trihydrate</td><td>Fisher</td><td>28300-74-5</td><td></td></tr><tr><td>Durapore Membrane Filters</td><td>Millipore</td><td>HVLP04700</td><td></td></tr><tr><td>Whatman #41 Filter Paper</td><td>Whatman</td><td>1441-150</td><td></td></tr><tr><td>Fixed Speed Reciprocal Shaker E6010</td><td>Eberbach Corporation</td><td>E6010.00</td><td></td></tr><tr><td>Disposable Culture Tubes</td><td>Fisher</td><td>14-961-29</td><td></td></tr><tr><td>Allegra 25R Centrifuge</td><td>Becker Coulter</td><td>U.S. 605168-AC</td><td></td></tr><tr><td>Parafilm</td><td>Bemis Company Inc PM 999</td><td>13-374-12</td><td></td></tr><tr><td>Oak Ridge Centrifuge Tubes</td><td>Nalgene</td><td>3119-0050</td><td></td></tr><tr><td>Fisherbrand 20mL HDPE Scintillation Vials with Urea Cap</td><td>Fisher</td><td>03-337-23C</td><td></td></tr><tr><td>Fisherbrand&amp;nbsp;Natural Polypropylene Jars with White Polypropylene Unlined Cap</td><td>Fisher</td><td>02-912-024A</td><td></td></tr><tr><td>0.45 membrane filters</td><td>Cole-Parmer</td><td>Item # UX-15945-25</td><td></td></tr><tr><td>100 ml digestion tubes</td><td>Fisher&amp;nbsp;</td><td>TC1000-0735</td><td></td></tr><tr><td>Glass funnels</td><td>Fisher</td><td>03-865</td><td></td></tr><tr><td>Spectronic 20 Genesys</td><td>Thermo-Fisher</td><td>4001-000</td><td></td></tr><tr><td>QuikChem</td><td>Latchat</td><td>8500</td><td></td></tr></tbody></table>

capturing flow-weighted water and suspended particulates from agricultural canals during drainage events

The purpose of this study is to describe the methods used to capture flow-weighted water and suspended particulates from farm canals during drainage discharge events. Farm canals can be enriched by nutrients such as phosphorus (P) that are susceptible to transport. Phosphorus in the form of suspended particulates can significantly contribute to the overall P loads in drainage water. A settling tank experiment was conducted to capture suspended particulates during discrete drainage events. Farm canal discharge water was collected in a series of two 200 L settling tanks over the entire duration of the drainage event, so as to represent a composite subsample of the water being discharged. Imhoff settling cones are ultimately used to settle out the suspended particulates. This is achieved by siphoning water from the settling tanks via the cones. The particulates are then collected for physico-chemical analyses.

The method described in this study allows us to capture water and particulate matter that is being discharged during pumping events in farms canals. The water and particulates that are collected are flow-weighted, which means that they are representative of the entire duration of the pumping event and not just a onetime snapshot; making it highly representative of the type of material being discharged. The water and suspended particulates can be stored to be analyzed for various physical ...

Watch this Scientific Journal Video about Capturing Flow-weighted Water and Suspended Particulates from Agricultural Canals During Drainage Events at JoVE.com

Capturing Flow-weighted Water and Suspended Particulates from Agricultural Canals During Drainage Events

Nutrients present in particulate form can contribute significantly to the overall loads in agricultural drainage waters. This study describes a novel method to capture flow-weighted water and suspended particulates from farm canal drainage over the entire duration of the drainage event.

The purpose of this study is to describe the methods used to capture flow-weighted water and suspended particulates from farm canals during drainage ...

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15.8K Views.  University of Florida. Nutrients present in particulate form can contribute significantly to the overall loads in agricultural drainage waters. This study describes a novel method to capture flow-weighted water and suspended particulates from farm canal drainage over the entire duration of the drainage event.

Video: Capturing Flow-weighted Water and Suspended Particulates from Agricultural Canals During Drainage Events

Colorimetric Paper-based Detection of Escherichia coli, Salmonella spp., and Listeria monocytogenes from Large Volumes of Agricultural Water

This protocol describes rapid colorimetric detection of Escherichia coli, Salmonella spp., and Listeria monocytogenes from large volumes (10 L) of agricultural waters. Here, water is filtered through sterile Modified Moore Swabs (MMS), which consist&#160;of a simple gauze filter enclosed in a plastic cartridge, to concentrate bacteria. Following filtration, non-selective or selective enrichments for the target bacteria are performed in the MMS. For colorimetric detection of the target bacteria, the enrichments are then assayed using paper-based analytical devices (&#181;PADs) embedded with bacteria-indicative substrates. Each substrate reacts with target-indicative bacterial enzymes, generating colored products that can be detected visually (qualitative detection) on the &#181;PAD. Alternatively, digital images of the reacted &#181;PADs can be generated with common scanning or photographic devices and analyzed using ImageJ software, allowing for more objective and standardized interpretation of results. Although the biochemical screening procedures are designed to identify the aforementioned bacterial pathogens, in some cases enzymes produced by background microbiota or the degradation of the colorimetric substrates may produce a false positive. Therefore, confirmation using a more discriminatory diagnostic is needed. Nonetheless, this bacterial concentration and detection platform is inexpensive, sensitive (0.1 CFU/ml detection limit), easy to perform, and rapid (concentration, enrichment, and detection are performed within approximately 24&#160;hr), justifying its use as an initial screening method for the microbiological quality of agricultural water.

Colorimetric Paper-based Detection of Escherichia coli, Salmonella spp., and Listeria monocytogenes from Large Volumes of Agricultural Water

A protocol involving integrated concentration, enrichment, and end-point colorimetric detection of foodborne pathogens in large volumes of agricultural water is presented here. Water is filtered through Modified Moore Swabs (MMS), enriched with selective or non-selective media, and detection is performed using paper-based analytical devices (&#181;PAD) imbedded with bacterial-indicative colorimetric substrates.

This protocol describes rapid colorimetric detection of Escherichia coli, Salmonella spp., and Listeria monocytogenes from large volumes (10 L) of ...

Design and Construction of an Urban Runoff Research Facility

As the urban population increases, so does the area of irrigated urban landscape. Summer water use in urban areas can be 2-3x winter base line water use due to increased demand for landscape irrigation. Improper irrigation practices and large rainfall events can result in runoff from urban landscapes which has potential to carry nutrients and sediments into local streams and lakes where they may contribute to eutrophication. A 1,000 m2 facility was constructed which consists of 24 individual 33.6 m2 field plots, each equipped for measuring total runoff volumes with time and collection of runoff subsamples at selected intervals for quantification of chemical constituents in the runoff water from simulated urban landscapes. Runoff volumes from the first and second trials had coefficient of variability (CV) values of 38.2 and 28.7%, respectively. CV values for runoff pH, EC, and Na concentration for both trials were all under 10%. Concentrations of DOC, TDN, DON, PO4-P, K+, Mg2+, and Ca2+ had CV values less than 50% in both trials. Overall, the results of testing performed after sod installation at the facility indicated good uniformity between plots for runoff volumes and chemical constituents. The large plot size is sufficient to include much of the natural variability and therefore provides better simulation of urban landscape ecosystems.

This paper describes the design, construction, and function of a 1,000 m2 facility containing 24 individual 33.6 m2 field plots equipped for measuring total runoff volumes with time and collection of runoff subsamples at selected intervals for quantification of chemical constituents in the runoff water from simulated home lawns.

As the urban population increases, so does the area of irrigated urban landscape. Summer water use in urban areas can be 2-3x winter base line water use ...

A Protocol for Conducting Rainfall Simulation to Study Soil Runoff

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

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

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

Watershed Planning within a Quantitative Scenario Analysis Framework

There is a critical need for tools and methodologies capable of managing aquatic systems within heavily impacted watersheds. Current efforts often fall short as a result of an inability to quantify and predict complex cumulative effects of current and future land use scenarios at relevant spatial scales. The goal of this manuscript is to provide methods for conducting a targeted watershed assessment that enables resource managers to produce landscape-based cumulative effects models for use within a scenario analysis management framework. Sites are first selected for inclusion within the watershed assessment by identifying sites that fall along independent gradients and combinations of known stressors. Field and laboratory techniques are then used to obtain data on the physical, chemical, and biological effects of multiple land use activities. Multiple linear regression analysis is then used to produce landscape-based cumulative effects models for predicting aquatic conditions. Lastly, methods for incorporating cumulative effects models within a scenario analysis framework for guiding management and regulatory decisions (e.g., permitting and mitigation) within actively developing watersheds are discussed and demonstrated for 2 sub-watersheds within the mountaintop mining region of central Appalachia. The watershed assessment and management approach provided herein enables resource managers to facilitate economic and development activity while protecting aquatic resources and producing opportunity for net ecological benefits through targeted remediation.

There is a critical need for tools and methodologies capable of managing aquatic systems in the face of uncertain future conditions. We provide methods for conducting a targeted watershed assessment that enables resource managers to produce landscape-based cumulative effects models for use within a scenario analysis management framework.

There is a critical need for tools and methodologies capable of managing aquatic systems within heavily impacted watersheds. Current efforts often fall ...

A Flow-through Exposure System for Evaluating Suspended Sediments Effects on Aquatic Life

This paper describes the Fish Larvae and Egg Exposure System (FLEES). The flow-through exposure system is used to investigate the effects of suspended sediment on various aquatic species and life stages in the laboratory by using pumps and automating delivery of sediment and water to simulate suspension of sediment. FLEES data are used to develop exposure-response curves between the effects on aquatic organisms and suspended sediment concentrations at the desired exposure duration. The effects data are used to evaluate management practices used to reduce the interactions between aquatic organisms and anthropogenic causes of suspended sediments. The FLEES is capable of generating total suspended solids (TSS) concentrations as low as 30 to as high as 800 mg/L, making this system an ideal choice for evaluating the effects of TSS resulting from many activities including simulating low ambient levels of TSS to evaluating sources of suspended sediments from dredging operations, vessel traffic, freshets, and storms.

A robust and flexible flow-through exposure system designed to maintain sediment in suspension is presented. The system is used to investigate the effects of suspended sediment on various aquatic species and life stages in the laboratory.

This paper describes the Fish Larvae and Egg Exposure System (FLEES). The flow-through exposure system is used to investigate the effects of suspended ...

Vegetated Treatment Systems for Removing Contaminants Associated with Surface Water Toxicity in Agriculture and Urban Runoff

Urban stormwater and agriculture irrigation runoff contain a complex mixture of contaminants that are often toxic to adjacent receiving waters. Runoff may be treated with simple systems designed to promote sorption of contaminants to vegetation and soils and promote infiltration. Two example systems are described: a bioswale treatment system for urban stormwater treatment, and a vegetated drainage ditch for treating agriculture irrigation runoff. Both have similar attributes that reduce contaminant loading in runoff: vegetation that results in sorption of the contaminants to the soil and plant surfaces, and water infiltration. These systems may also include the integration of granulated activated carbon as a polishing step to remove residual contaminants. Implementation of these systems in agriculture and urban watersheds requires system monitoring to verify treatment efficacy. This includes chemical monitoring for specific contaminants responsible for toxicity. The current paper emphasizes monitoring of current use pesticides since these are responsible for surface water toxicity to aquatic invertebrates.

This article summarizes the design attributes and the effectiveness of treatment systems that treat urban stormwater and agriculture irrigation runoff to remove pesticides and other contaminants associated with aquatic toxicity.

Urban stormwater and agriculture irrigation runoff contain a complex mixture of contaminants that are often toxic to adjacent receiving waters. Runoff may ...

Continuous Instream Monitoring of Nutrients and Sediment in Agricultural Watersheds

Pollutant concentrations and loads in watersheds vary considerably with time and space. Accurate and timely information on the magnitude of pollutants in water resources is a prerequisite for understanding the drivers of the pollutant loads and for making informed water resource management decisions. The commonly used &#34;grab sampling&#34; method provides the concentrations of pollutants at the time of sampling (i.e., a snapshot concentration) and may under- or overpredict the pollutant concentrations and loads. Continuous monitoring of nutrients and sediment has recently received more attention due to advances in computing, sensing technology, and storage devices. This protocol demonstrates the use of sensors, sondes, and instrumentation to continuously monitor in situ nitrate, ammonium, turbidity, pH, conductivity, temperature, and dissolved oxygen (DO) and to calculate the loads from two streams (ditches) in two agricultural watersheds. With the proper calibration, maintenance, and operation of sensors and sondes, good water quality data can be obtained by overcoming challenging conditions such as fouling and debris buildup. The method can also be used in watersheds of various sizes and characterized by agricultural, forested, and/or urban land.

With the advancement of technology and the rise in end-user expectations, the need and use of higher temporal resolution data for pollutant load estimation has increased. This protocol describes a method for continuous in situ water quality monitoring to obtain higher temporal resolution data for informed water resource management decisions.

Pollutant concentrations and loads in watersheds vary considerably with time and space. Accurate and timely information on the magnitude of pollutants in ...

Continuous Hydrologic and Water Quality Monitoring of Vernal Ponds

Vernal ponds, also referred to as vernal pools, provide critical ecosystem services and habitat for a variety of threatened and endangered species. However, they are vulnerable parts of the landscapes that are often poorly understood and understudied. Land use and management practices, as well as climate change are thought to be a contribution to the global amphibian decline. However, more research is needed to understand the extent of these impacts. Here, we present methodology for characterizing a vernal pond's morphology and detail a monitoring station that can be used to collect water quantity and quality data over the duration of a vernal pond's hydroperiod. We provide methodology for how to conduct field surveys to characterize the morphology and develop stage-storage curves for a vernal pond. Additionally, we provide methodology for monitoring the water level, temperature, pH, oxidation-reduction potential, dissolved oxygen, and electrical conductivity of water in a vernal pond, as well as monitoring rainfall data. This information can be used to better quantify the ecosystem services that vernal ponds provide and the impacts of anthropogenic activities on their ability to provide these services.

Understanding the ecosystem services and processes provided by vernal ponds and the impacts of anthropogenic activities on their ability to provide these services requires intensive hydrologic monitoring. This sampling protocol using in-situ monitoring equipment was developed to understand the impact of anthropogenic activities on water levels and quality.

Vernal ponds, also referred to as vernal pools, provide critical ecosystem services and habitat for a variety of threatened and endangered species. ...

Wastewater Irrigation Impacts on Soil Hydraulic Conductivity: Coupled Field Sampling and Laboratory Determination of Saturated Hydraulic Conductivity

Since the early 1960s, an alternative wastewater discharge practice at The Pennsylvania State University has been researched and its impacts monitored. Rather than discharging treated wastewater to a stream, and thereby directly impacting the stream quality, the effluent is applied to forested and cropped land managed by the University. Concerns related to reductions in soil hydraulic conductivity occur when considering wastewater reuse. The methodology described in this manuscript, matching soil sample size with the size of the laboratory-based hydraulic conductivity measurement apparatus, provides the benefits of a relatively rapid collection of samples with the benefits of controlled laboratory boundary conditions. The results suggest that there may have been some impact of wastewater reuse on the soil&#39;s ability to transmit water at deeper depths in the depressional areas of the site. Most of the reductions in the soil hydraulic conductivity in the depressions appear to be related to the depth from which the sample was collected, and by inference, associated with the soil structural and textural differences.

Here we present a methodology which matches a soil sample size and a hydraulic conductivity measurement device to prevent the so-called wall flow along the inside of the soil container from being erroneously included in water flow measurements. Its use is demonstrated with samples collected from a wastewater irrigation site.

Since the early 1960s, an alternative wastewater discharge practice at The Pennsylvania State University has been researched and its impacts monitored. ...

Parameterizing V-notch Weir Equations for Flow Monitoring in a Drainage Control Structure

Accurate estimation of drainage discharge (flow rate or water volume per unit time) is essential for calculating nutrient loads delivered to surface water and assessing the performance of edge-of-field conservation practices. Determining drainage flow rates requires monitoring the head in a drainage control structure and applying an appropriate equation for the weir installed in the structure. Previous studies that developed calibrated equations for weirs in control structures have produced different equations (i.e., different weir flow equation coefficients) for the same type of weir and control structure size. This study describes procedures for setting up experimental water flow rate and head measurements within a drainage control structure and developing a weir equation for flows contained within a V-notch weir. Additionally, the procedure for obtaining a weir equation for overtopping flows -- when the water level exceeds the top of the V-notch weir -- is outlined. This process involves using the weir equation developed in the laboratory for a V-notch weir and an online tool, the &#34;Weir Flow Equation Coefficients Calculator&#34;, developed by the authors. The online tool can also generate weir flow equation coefficients for both V-notch-contained and overtopping flows across various sizes of Agri Drain water control structures, even when users lack site-specific flow rate vs. head relationship.

This protocol describes methods for obtaining weir flow equation coefficients for a V-notch weir within a drainage control structure using (1) a laboratory calibration procedure and (2) an online tool, the "Weir Flow Equation Coefficients Calculator", developed by the authors. These methods apply to flows contained within the V-notch and overtopping flows.

Accurate estimation of drainage discharge (flow rate or water volume per unit time) is essential for calculating nutrient loads delivered to surface water ...

Capturing Flow-weighted Water and Suspended Particulates from Agricultural Canals During Drainage Events

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Chapters in this video

Colorimetric Paper-based Detection of Escherichia coli, Salmonella spp., and Listeria monocytogenes from Large Volumes of Agricultural Water

Design and Construction of an Urban Runoff Research Facility

A Protocol for Conducting Rainfall Simulation to Study Soil Runoff

Watershed Planning within a Quantitative Scenario Analysis Framework

A Flow-through Exposure System for Evaluating Suspended Sediments Effects on Aquatic Life

Vegetated Treatment Systems for Removing Contaminants Associated with Surface Water Toxicity in Agriculture and Urban Runoff

Continuous Instream Monitoring of Nutrients and Sediment in Agricultural Watersheds

Continuous Hydrologic and Water Quality Monitoring of Vernal Ponds

Wastewater Irrigation Impacts on Soil Hydraulic Conductivity: Coupled Field Sampling and Laboratory Determination of Saturated Hydraulic Conductivity

Parameterizing V-notch Weir Equations for Flow Monitoring in a Drainage Control Structure