The authors would like to thank the Pennsylvania State University Office of Physical Plant (OPP) for funding to support this research. Additionally, we would like to thank Drs. Elizabeth W. Boyer, David A. Miller, and Tracy Langkilde at The Pennsylvania State University for their collaborative support of this project.

1. Conducting a Survey of a Vernal Pond Morphology
<ol>
	<li>Select a location to designate as the benchmark and mark it with a small survey or marking flag. 
	NOTE: The location should be a higher elevation than the pond and have line-of-sight from all locations across the pond.</li>
	<li>Assign the benchmark a reference elevation; the exact number does not matter, it simply provides a reference to which all other elevations can be compared.</li>
	<li>Using a tape measure and marking flags, make transects at a 3 ...

<ol>
	<li>Korfel, C. A., Mitsch, W. J., Hetherington, T. E., Mack, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydrology+physiochemistry,+and+amphibians+in+natural+and+created+vernal+pool+wetlands.">Hydrology physiochemistry, and amphibians in natural and created vernal pool wetlands.</a> Restor. Ecol. 18 (6), 843-854 (2010).</li><li>Colburn, E. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Vernal Pools: Natural History and Conservation. , (2004).</li><li>Collins, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amphibian+decline+and+extinction:+What+we+know+and+what+we+need+to+learn.">Amphibian decline and extinction: What we know and what we need to learn.</a> Dis Aquat Org. 92, 93-99 (2013).</li><li>Wake, D. B., Vredenburg, V. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Are+we+in+the+midst+of+the+sixth+mass+extinction?+A+view+from+the+world+of+amphibians.">Are we in the midst of the sixth mass extinction? A view from the world of amphibians.</a> Proc Nat Acad Sci USA. 105, 11466-11473 (2008).</li><li>IUCN. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Conservation International and Nature Conservancy. , (2004).</li><li>Smits, A. P., Skelly, D. K., Bolden, S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amphibian+intersex+in+suburban+landscapes.">Amphibian intersex in suburban landscapes.</a> Ecosphere. 5 (1), 11 (2014).</li><li>Brooks, R. T., Miller, S. D., Newsted, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+impact+of+urbanization+on+water+and+sediment+chemistry+of+ephemeral+forest+pools.">The impact of urbanization on water and sediment chemistry of ephemeral forest pools.</a> J. Freshwater Ecol. 17 (3), (2002).</li><li>Czajka, C. P., Londry, K. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Anaerobic+transformation+of+estrogens.">Anaerobic transformation of estrogens.</a> Environ. Sci. Technol. 367, 932-941 (2006).</li><li>Dytczak, M. A., Londry, K. L., Oleszkiewicz, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biotransformation+of+estrogens+in+nitrifying+activated+sludge+under+aerobic+and+alternating+anoxic/aerobic+conditions.">Biotransformation of estrogens in nitrifying activated sludge under aerobic and alternating anoxic/aerobic conditions.</a> Water Environ. Res. 80 (1), 47-52 (2008).</li><li>Field, H. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Landscape Surveying. , (2012).</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=Solar+Angle+Calculator.">Solar Angle Calculator.</a> Solar Electricity Handbook. , (2017).</li><li>Brooks, R. T., Hayashi, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Depth-area-volume+and+hydroperiod+relationships+of+ephemeral+(vernal)+forest+pools+in+southern+New+England.">Depth-area-volume and hydroperiod relationships of ephemeral (vernal) forest pools in southern New England.</a> Wetlands. 22 (2), 247-255 (2002).</li><li>Laposata, M. M., Dunson, W. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+spray-irrigated+wastewater+effluent+on+temporary+pond-breeding+amphibians.">Effects of spray-irrigated wastewater effluent on temporary pond-breeding amphibians.</a> Ecotox. Environ. Safe. 46 (2), 192-201 (2000).</li><li>Qian, Y. L., Mecham, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long-term+effects+of+recycled+wastewater+irrigation+on+soil+chemical+properties+on+golf+course+fairways.">Long-term effects of recycled wastewater irrigation on soil chemical properties on golf course fairways.</a> Agron. J. 97 (3), 717-721 (2005).</li><li>Karraker, N. E., Gibbs, J. P., Vonesh, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Impacts+of+road+deicing+salt+on+the+demography+of+vernal+pool-breeding+amphibians.">Impacts of road deicing salt on the demography of vernal pool-breeding amphibians.</a> Ecol. Appl. 18 (3), (2008).</li><li>Gall, H. E., Jafvert, C. T., Jenkinson, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Integrating+hydrograph+modeling+with+real-time+monitoring+to+generate+hydrograph-specific+sampling+schemes.">Integrating hydrograph modeling with real-time monitoring to generate hydrograph-specific sampling schemes.</a> J. Hydrol. 393, 331-340 (2010).</li><li>Gall, H. E., Sassman, S. A., Lee, L. S., Jafvert, C. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hormone+discharges+from+a+Midwest+tile-drained+agroecosystem+receiving+animal+wastes.">Hormone discharges from a Midwest tile-drained agroecosystem receiving animal wastes.</a> Environ. Sci. Technol. 45, 8755-8764 (2011).</li><li>Pittman, S. E., Jendrek, A. L., Price, S. J., Dorcas, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Habitat+selection+and+site+fidelity+of+Cope's+Gray+Treefrog+(Hyla+chrysoscelis)+at+the+aquatic-terrestrial+ecotone.">Habitat selection and site fidelity of Cope's Gray Treefrog (Hyla chrysoscelis) at the aquatic-terrestrial ecotone.</a> J. Hepatol. 42 (2), 378-385 (2008).</li><li>Vandewege, M. W., Swannack, T. M., Greuter, K. L., Brown, D. J., Forstner, M. R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Breeding+site+fidelity+and+terrestrial+movement+of+an+endangered+amphibian,+the+Houston+Toad+(Bufo+Houstonensis).">Breeding site fidelity and terrestrial movement of an endangered amphibian, the Houston Toad (Bufo Houstonensis).</a> Herpet. Conserv. Bio. 8 (2), 435-446 (2013).</li><li>Homan, R. N., Atwood, M. A., Dunkle, A. J., Karr, S. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Movement+orientation+by+adult+and+juvenile+wood+frogs+(Rana+Sylvatica)+and+american+toads+(Bufo+Americanus)+over+Multiple+Years.">Movement orientation by adult and juvenile wood frogs (Rana Sylvatica) and american toads (Bufo Americanus) over Multiple Years.</a> Herpet. Conserv. Bio. 5 (1), 64-72 (2010).</li></ol>

The authors have nothing to disclose.

Significance with Respect to Existing Methods
While monitoring of streams has well-established methodologies developed by the United States Geological Survey (USGS), no such widespread monitoring program exists for understanding vernal pond dynamics. This protocol seeks to provide guidance for how to begin to approach hydrologic and water quality monitoring research at a vernal pond site, with the goal of understanding how physical and chemical factors may be changing over tim...

Vernal ponds are temporary, shallow wetlands that typically contain water from fall to spring and are often dry during the summer months. The inundation period of vernal ponds, generally referred to as the hydroperiod, is primarily controlled by precipitation and evapotranspiration1. 
Vernal ponds can also be referred to as vernal pools, ephemeral ponds, temporary ponds, seasonal ponds, and geographically isolated wetlands2. In the northeastern United States, vernal ponds are most often characterized by the critical habitat they provide for amphibians, serving as the breeding grounds and providing support during early life stages (i.e., tadpoles) and metamorphosis. In California, vernal ponds are characterized by the unique vegetation and endangered plant species that they support2. 
These habitats are increasingly threatened due to land use and climate change, and amphibian populations are experiencing a significant global decline largely due to anthropogenic activities3,4. Water quality concerns due to pollution are also thought to be contributing factors in recent amphibian declines globally5. Furthermore, recent studies have revealed an increased occurrence of intersex characteristics in frogs inhabiting vernal ponds impacted by human wastewater6. There is therefore a need to conduct more intensive monitoring of both natural and impacted vernal ponds to better understand the contributors to the global amphibian decline.
The physical parameters of vernal ponds that need to be measured and monitored include the pond morphology and water level. The morphology is the geometry of the pond, and is developed by conducting a survey to determine changes in elevation across the pond. The survey data are then used to establish a stage-storage curve, which enables the volume of the pond to be estimated based on water level measurements. Because the water level in a vernal pond is heavily influenced by precipitation, measurements should be made at a high temporal resolution to best understand both short (i.e., on the order of minutes to hours) and long-term fluctuations (i.e., on the order of months to years) in water level. 
Water quality parameters of interest that are known to affect the function of vernal ponds include temperature, pH, electrical conductivity, dissolved oxygen levels, and oxidation-reduction potential. These parameters can all be measured in situ with relatively cheap technologies and sensor networks. Some water quality parameters of interest such as some nutrient species (i.e., total Kjeldahl nitrogen) and other pollutants (i.e., emerging contaminants) require samples to be collected and brought to a laboratory for processing and analysis. 
Critical parameters that affect the ability of vernal ponds to function as appropriate habitat for breeding amphibians and the early developmental stages of tadpoles include water level, pH, and dissolved oxygen concentration. Compared to vernal ponds located in relatively pristine landscapes, elevated levels of electrical conductivity, higher pH, reduced dissolved oxygen concentrations, and high nutrient concentrations have been recorded in vernal ponds impacted by anthropogenic activities2,7. Reducing or anaerobic conditions may occur in these habitats, particularly ones that are impacted by anthropogenic activities. This can cause a shift in the microbiological community, altering the nutrient cycling within the pond and potentially reducing degradation of endocrine disrupting compounds and other pollutants8,9.
The goal of this paper is to provide information for how to establish a station for monitoring the water quantity and quality of a vernal pond. This method can be applied to any vernal pond, but requires access to the site (i.e., the site must be on public property or have land-owner permission to install equipment).

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	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">CR1000</td>
			<td style="width:143px;">Campbell Scientific</td>
			<td style="width:119px;">16130-23</td>
			<td style="width:415px;">Measurement and Control Datalogger</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">ENC12/14-SC-MM</td>
			<td style="width:143px;">Campbell Scientific</td>
			<td style="width:119px;">30707-88</td>
			<td>Weatherproof Enclosure Box (12&#34; x 14&#34;)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">CS451-L</td>
			<td style="width:143px;">Campbell Scientific</td>
			<td style="width:119px;">28790-82</td>
			<td>Pressure Transducer</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">CM305-PS</td>
			<td style="width:143px;">Campbell Scientific</td>
			<td style="width:119px;">20570-3</td>
			<td>47&#34; Mounting Pole (Tripod)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">TE525-L</td>
			<td style="width:143px;">Texas Electronics</td>
			<td style="width:119px;">7085-111</td>
			<td>Tipping Bucket Rain Gauage (0.01 inch)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">CS511-L</td>
			<td style="width:143px;">Campbell Scientific</td>
			<td style="width:119px;">26995-41</td>
			<td>Dissolved Oxygen Sensor</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">SP10</td>
			<td style="width:143px;">Campbell Scientific</td>
			<td style="width:119px;">5278</td>
			<td>10 W Solar Panel</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">PS150-SW</td>
			<td style="width:143px;">Campbell Scientific</td>
			<td style="width:119px;">29293-1</td>
			<td>12 V Power Supply with Voltage Regulator &#38; 7 Ah Rechargeable Battery</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">CSIM11-ORP</td>
			<td style="width:143px;">Wedgewood Analytical</td>
			<td style="width:119px;">22120-72</td>
			<td>Oxidation-reduction potential probe</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">CSIM11-L</td>
			<td style="width:143px;">Wedgewood Analytical</td>
			<td style="width:119px;">22119-151</td>
			<td>pH probe</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">CS547A-L</td>
			<td style="width:143px;">Campbell Scientific</td>
			<td style="width:119px;">16725-229</td>
			<td>Water conductivity probe</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">A547</td>
			<td style="width:143px;">Campbell Scientific</td>
			<td style="width:119px;">12323</td>
			<td>CS547(A) Conductivity Interface</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">CST/berger SAL &#39;N&#39; Series Automatic Level Package</td>
			<td style="width:143px;">CST/berger</td>
			<td>55-SLVP32D</td>
			<td>Automatic Survey Level, Tripod, and 8&#39; survey rod</td>
		</tr>
	</tbody>
</table>

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.

Vernal ponds can exhibit a wide range of morphology, with profiles ranging from convex to straight slope to concave. Example morphology for a vernal pond in Central Pennsylvania is shown in Figure 1, along with the results of the stage-storage curve for this pond (Figure 2, Table 1). Maximum pond depth is not a strong indicator of surface area, as hydroperiod has only a weak correlation with pond morphology<sup c...

Watch this Scientific Journal Video about Continuous Hydrologic and Water Quality Monitoring of Vernal Ponds at JoVE.com

Continuous Hydrologic and Water Quality Monitoring of Vernal Ponds

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. ...

The overall goal of this procedure is to establish a monitoring station that can continuously monitor the hydrology and water quality of a vernal pond. This method can provide insight to the functionality of vernal ponds, such as how human activities are impacting these sensitive aquatic ecosystems. The main advantage of this technique is that allows us to know at a high temporal resolution what the major water quality parameters are that maybe influencing contaminant fate and transport.Though This method can provide insight into vernal pond ecosystem and it can also be applied to other systems such as lakes or streams. Visual demonstration of this method is helpful as the setup and installation steps can be confusing when under this equipment. This video focuses on the installation of the vernal monitoring pond monitoring system.Details on surveying a vernal pond morphology and calculation of a pond's state storage curve are both provided in the text protocol. The sensors for this study this include a pressure transducer, a dissolved oxygen sensor, an oxidation reduction probe, an electrical conductivity probe, a pH probe, and a tipping bucket rain gauge. They should all be calibrated prior to the field installation.Apart from the rain gauge, secure all of their sensors to a cinder block or a wooden stake so they will stay at the bottom of the pond, or at a depth of interest. To accomplish this use hose clamps or zip ties. When doing so be sure to attach the dissolved oxygen sensor at an angle at which oxygen will diffuse across its membrane.Also, install the pressure transducer upright, so it measures the pressure of the water column above it. Position the sensors toward the center of the pond where they are unlikely to get dry during the study period. Measure and note the distance between the sensors in the deepest part of the pond, as this figure is needed for some calculations.The sensor wires are vulnerable to mice or other animals that may chew on them such as when the water level is low. So run the wire through a PVC pipe for protection. Extend the pipe to end of the pond where the wires will engage with the data-logger.Next set up the data-logger. To set up the data-logger install a tripod near the pond's edge and secure it to the ground using stakes. Attach a radio antennae if the data needs to be transmitted wirelessly.Then onto the tripod attach the data box for the data-logger and a 12 volt battery with voltage regulator. Be sure to leave room on the tripod to mount a solar panel. Next attach a 10 watt solar panel to the top of the tripod, and angle it towards the sun;use a solar angle calculator to optimize the angle.Now if there is there is room on the tripod attach a rain gauge, otherwise attach it to a wooden stake or metal pole near the edge of the pond. The rain gauge should be under the same amount of tree cover as the bulk of the pond surface area. Now set up the central data-logger, program it to record data on 15 minute intervals, feed all the sensor and solar panel wires into the enclosure box through the hole at the bottom of the box.Then connect all sensors to the wiring panel in accordance with the sensor's instructions or the wiring diagram. Next, connect the solar panel wires to the 12 volt battery to recharge the battery. Now, connect the battery to power input panel.Then place a desiccant pack inside the enclosure box to reduce the likelihood of moisture damage to the electronics. If possible test the system connected to a field laptop using the serial cable and use the software to ensure that the sensor network is working properly. Then plug the gap in the wire hole with clay to keep out insects and water.Finally, close the enclosure box. If security is a concern close the box with a padlock. Going forward visit the site frequently and follow the manufacturer's recommendations for periodic sensor calibration, which can be weekly.Vernal ponds can exhibit a wide range of morphology with profiles ranging from convex, to straight-slope, to concave. Precipitation, evapotranspiration, and ground water flow are important factors in determining the hydrology of vernal ponds. A study of three ponds was conducted during the breeding and metamorphosis period of wood frogs in the Northeastern United States.The ponds were selected because their water levels changes are caused by rainfall and by waste water irrigation events. The sensors were placed at the bottoms of the ponds. In general, the temperature of the ponds increased over the study period but decreased in response to effluent irrigation events.The pH was relatively consistent for the majority of the study period and as expected. The electrical conductivity of the ponds increased over the course of the study period likely due to higher electrical conductivity of waste water compared to rain water. Dissolved oxygen concentration and oxidation reduction potential generally followed a similar trend.Dissolved oxygen followed a common trend of being inversely related to temperature, which related to mats of duckweed that grow on these ponds during this time of year. Once mastered, this type of thing can be done in four to six hours if performed properly. Plan to spend at least half the day in the field.It's important to remember when you're doing this kind of research to secure the proper permits or landownership permissions, depending on whether you're doing on private or public property. Also don't forget that work with electricity can be extremely hazardous and that all the equipment must be properly grounded. Following this procedure, other methods like collecting ground water samples, can be performed in order to answer additional questions, like how the reflex conditions in the pond may affect the persistence of emerging contaminants and potentially, the metamorphosis of amphibians.

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9.1K Views.  Pennsylvania State University. The overall goal of this procedure is to establish a monitoring station that can continuously monitor the hydrology and water quality of a vernal pond. This method can provide insight to the functionality of vernal ponds, such as how human activities are impacting these sensitive aquatic ecosystems. The main advantage of this technique is that allows us to know at a high temporal resolution what the major water quality parameters are that maybe influencing contaminant fate and transport.