NE1438: Hydropedology of Vernal Pool Systems
(Multistate Research Project)
NE1438: Hydropedology of Vernal Pool Systems
Duration: 10/01/2014 to 09/30/2019
Statement of Issues and Justification
Vernal pools are one of the most ecologically valued types of inland wetlands. These ecosystems provide habitat for numerous rare and endangered plants and animals and provide numerous ecosystem functions within upland landscapes. By definition, vernal pools (sometimes known as seasonal ponds) are depressional wetlands that typically contain surface water during the dormant season (late fall or winter through spring) and for part of the growing season before drying during summer or early fall. In the northeast there are a range of different types of vernal pools including kettle holes, sink holes, Delmarva Bays, and oxbows. Over the last decade northeast pedologists have been working together under multistate projects NE-1021 and NE-1038 to develop expertise in the identification, characterization, classification, and land use interpretations of hydromorphic soils in different types of wetlands. One of the conclusions from our studies was that although vernal pools occur throughout the northeast, at a regional level we have a very limited understanding of these wetlands. In this project we will study a range of vernal pools throughout the northeast region.
These studies are necessary because of a wide-range of stakeholder driven issues and concerns. Wetland identification, protection, and restoration is a multi-million dollar industry in the United States. State, regional, and federal agencies are working to develop and enforce regulations to maintain, enhance, increase, and protect our nations wetlands. Non-profit organizations such as The Nature Conservancy, Sierra Club, World Wildlife Fund, and Ducks Unlimited have joined forces to support many of these efforts. In contrast, economic development can be stymied by over-regulation and thus developers argue for a balance between natural resource protection and development. In between these arguments are often the small isolated wetlands known as vernal pools that have already suffered serious loss (some regions report as much as a 90% loss of vernal pool wetlands, mostly due to draining for agriculture). Although many states protect vernal pools in their wetlands regulations, federal protection under the Clean Water Act is limited because these systems are often not connected at the surface to the larger wetlands. Thus, showing a connectedness to the regional hydrology could be an important issue regarding their protection.
The value of vernal pool ecosystems is registered in a range of functions. These are isolated wetlands on the landscape. Thus, they often hold the last remaining combination of plants and animals that represent the original ecosystem. For example, amphibians such as wood frogs and spotted salamanders require seasonal ponds to breed and develop. These herps lay their eggs in the ponds during the spring where the young develop into adults. As adults, they move into the surrounding uplands. If the ponds are dry all year they cannot breed, but if the ponds stay inundated all year (a pond/lake) fish will survive and eat the frog and salamander eggs and larval stages. Development of the young requires a duration of surface inundation, known as a hydroperiod, which varies in time depending upon the pools size and seasonal precipitation. Because there is generally a high degree of temporal heterogeneity in length of time pools are inundated within a watershed, and the factors governing the timing of surface inundation are poorly understood, developing an understanding of vernal pool hydroperiod across the landscape and region is necessary. We propose to measure hydroperiods in these studies and develop and test not only hydric soil indicators for these soils and landscapes, but also assess if inundation indicators can be developed for vernal pool wetlands to predict hydroperiods.
In addition to temporal heterogeneity in pool hydroperiod, there is considerable spatial variation in densities of vernal pools across a region. What factors control spatial distribution of vernal pools is unclear. This could be a function of the type of vernal pool. For example, Delmarva Bays generally occur in groups within a specific range in elevation, but beyond that range, the bays are absent from the landscape. In this project we will test spatial tools such as terrain or image analysis to map and quantify the size, shape, and density of vernal pools across landscapes of the region. This is important because at the scales of most soil surveys and NWI maps, vernal pool wetlands are often missed. These analysis will also be used to estimate the extent that vernal pools that have been altered (mostly drained) to identify the number of vernal pool wetlands that have been lost (or potentially able to be restored.
Hydroperiod is clearly a function of climate and hydrology. Our studies will provide a 5 year record of the hydrology of a range of vernal pools across the region. These data can be used to set hydrologic goals for the restoration of vernal pools and assess the effects of future climate change on hydroperiod of these ecosystems. In addition, we will use analysis of long-term climate data to assess relationships between climate and hydrology. Such analysis will allow us to model the effects of climate change on seasonal pond wetlands in the northeast.
Our previous studies of carbon pools (stocks) has shown that kettle holes (glacially derived vernal pools) contain the largest carbon pools on the landscape (over 600 Mg/ha in the upper meter of the soil). There are no region-wide studies, however, that show these same trends in non-glaciated regions. Since vernal pool ecosystems include areas that are inundated adjacent to those that are only seasonally saturated to the surface we can test the effect of inundation on the accumulation of carbon. We will monitor redox conditions within the vernal pools to develop relationships between carbon pools, flux, and cumulative anaerobic conditions. We will examine spatial variability in carbon accumulation using ground penetrating radar and electromagnetic induction. We can use these data to establish models to predict the effects of climate change (increases or decreases in precipitation and temperature) on carbon storage and flux in the soils of vernal pools.
Related, Current and Previous Work
Brief review of related NE vernal pool literature
Vernal pools, which are also known as seasonal or temporary ponds, are depressional wetlands that typically contain surface water during the dormant season (late fall or winter through spring) and for part of the growing season before drying during summer (Keeley and Zedler, 1996; Brooks and Hayashi, 2002). Vernal pools are found in many geomorphic forms (Rhienhart et al., 2007). In the northeastern US they are typically found as oxbow scars, kettle holes, and Delmarva and Carolina Bays. These pools are typically classified under the Cowardin et al (1979) system as seasonally flooded, pooled, scrub-shrub wetlands. Several amphibians (frogs, toads, and salamanders) require vernal pools for breeding (Keeney and Burne, 2000). Some of the populations of these species are listed in northeastern states as of concern (DeGraaf and Rudis, 1983) and warrant protection at the local, state, and federal level (Calhoun and DeMaynadier, 2008; Colburn, 2004; Cutko, 1997; Skidds et al., 2005; 2007). Thus, there is a growing need for assessments of the hydrologic and edaphic factors that control the vernal pools habitat that breeding amphibians are reliant upon.
In addition to providing breeding habitat for a range of amphibians, vernal pools support diverse and unique communities of plants (Lin, 1970; Bliss and Zedler, 1998) and invertebrates (Wiggins et al., 1980; Brooks, 2000). For example, in their review of vernal pool flora in the northeastern US, Cutko and Rawinski (2008) identified over 400 associated plant species (20 of these plants are listed as at-risk in New England). Models designed to predict such biodiversity in small, isolated wetlands such as vernal pools have found that duration of surface inundation, or hydroperiod, is one of key variables in predictive models (Schneider and Frost 1996, Wellborn et al. 1996). Ecologists have shown that hydroperiod is one of best predictors of community structure for plants (Ebert and Balko 1987), invertebrates (Schneider and Frost 1996, Brooks 2000) and amphibians (Snodgrass et al., 2000a, 2000b, Egan, 2001). Hydroperiod varies depending upon the pool and the year (Semlitsch 2000a). Because there is generally a high degree of temporal heterogeneity in length of time pools are inundated within a watershed (Egan, 2001), and the factors governing the timing of surface inundation are poorly understood. Thus, developing an understanding vernal pool hydroperiod across the region would aid in further explaining flora and fauna diversity.
Hydroperiod is a function of the quantity, frequency, and types of hydrologic inputs and outputs in a wetland basin over the course of the year (Novitzki, 1989; Carter, 1997; Epstein, 1997). These inputs and outputs, in turn, are influenced by the nature of the geomorphic surface, surficial geologic deposits, and soils beneath the basin and the basins position on the landscape (Motts and OBrien 1981; Brown et al., 1988; Lide et al., 1995; Carter, 1997; Pyle, 1998). In the northeast there a number of geomorphic settings where vernal pools have formed. Oxbow scars or depressions form on the river terraces that are common along the higher order streams of most watersheds in the region. Over time, the channels of these streams have deposited alluvial materials and shifted or meandered across the floodplains leaving stranded channels or oxbow scars in which vernal pools have formed (Ritter et al., 2011). On the coastal plain, Delmarva Bays are the most common geomorphic feature associated with vernal pools. These depressions formed in blow-outs and Pleistocene-aged dunal swales (Stolt and Rabenhorst, 1987). In the glaciated northeast kettle holes (depressions) occur in kettle-knob topography of the moraines that mark the leading edge of the melting glacier and the ice-block depressions of the outwash plain (Schafer and Hartshorn, 1965; Lawson, 1995; Boothroyd and Sirkin, 2002). While it is clear that different geomorphic processes govern the range and distribution of vernal pools in the region, we have no idea how hydroperiod varies among the pools on the different geomorphic surfaces and landforms.
Current and related work
The current NE-1038 project has established a framework for the systematic study of hydromorphic, hydric, and subaqueous soils across the northeastern US. Results from the proposed new NE multistate project will help us to develop an understanding of how vernal pool ecosystems differ across the region in distribution, hydrology, periods of inundation (hydroperiod), redox chemistry, and carbon storage, flux, and accounting. In addition, we will continue our region-wide focus on hydric soils and hydric indicators to determine if there is a need for additional hydric soil indicators for vernal pool ecosystems. We will use our data to develop empirical and spatial quantitative models to predict and represent the landscape distribution of vernal pools, and how climatic change may affect these wetland ecosystems. A continuation of this project will provide a forum to advance our knowledge of these systems and the associated soils and provide an outlet for the dissemination of our knowledge across the region to stakeholders that are seeking answers to their use, management, and restoration questions.
Working within the proposed regional framework will allow for testing of hypotheses across climatic gradients, across parent material types (coastal plain, residual, and glacial), and among different types and settings of vernal pools. Testing these hypotheses is not possible for a single investigator working within a single state and must be done at the regional level. Addressing these questions within a regional framework is also critical because the major agencies that use the soils information that pedologists collect, such as USDA-NRCS, USACOE, USEPA, all work in a region-wide context. In addition, working groups such as the New England Hydric Soil Technical Committee and Mid-Atlantic Hydric Soils Committee, who offer guidance to regional regulatory bodies like the New England Water Pollution Control Commission (http://www.neiwpcc.org/), need soils information that is not restricted by state boundaries. Recent focus of the USACOE and other federal agencies to develop regional supplements as amendments to the 1987 Wetlands Delineation Manual (Environmental Laboratory, 1987) provide additional incentive to work region-wide in applied research. Data gathered, relationships that are established, and interpretations that are made are therefore much more meaningful to the user if the science was tested within a region-wide context. These studies also take advantage of the range of experiences and skills of the pedologists across the region.
Improve our understanding at a regional scale of how vernal pool ecosystems differ in distribution, hydrology, hydroperiod, redox chemistry, and carbon storage and flux. Along with this we will develop a better understanding of the effects of hydrology and temperature on carbon pools and sequestration in wetlands along a temperature gradient.
Identify the need for additional hydric soil indicators for northeast vernal pools. As such, if needed we will monitor the saturation and reducing conditions in the identified soils and develop new hydric soil indicators for inclusion as part of the National Indicators of Hydric Soils for the Northeast Supplement.
Develop morphometric indices of the hydroperiod within vernal pools.
Estimate the current density of vernal pools within each of our subregions and develop predictions of the numbers that have been lost because of disturbance.
MethodsSite Selection Seven sites will be selected across the NE region in proximity to locations of the PIs. Recognizing that there is substantial variation in the nature of vernal pools as a function of physiography and geomorphology, it is anticipated that these seven sites will be distributed among three groups as shown in Table 1. All sites will include vernal pool wetlands having clearly-identifiable hydrological zones (ponded, saturated, and unsaturated) with gradual boundaries between the zones. Spatial Distribution and Analysis Using GIS technology and available imagery, estimates will be made of the size, shape, and density of vernal pools across landscapes of the region. Where possible, these data will also be used to evaluate the extent to which vernal pools may have been altered (drained or filled). These analyses may permit estimation of the number of vernal pool wetlands that have been lost or those that may potentially be restored. Plot Layout and Experimental Design In the wetland at each study site, 3 hydrological zones will be identified, corresponding to the predominant soil, plant, and water characteristics at each location (Figure 1). Zone 1 is seasonally ponded, and typically contains emergent, shrub or woody vegetation. Zone 1 usually becomes ponded in the Winter and early Spring and then dries out sometime before or during the Summer season. Zone 2 is a wetland transitional zone marked by saturation, but not significant ponding. Wetland vegetation and hydric soils are expected to be present in zone 2, as in zone 1. Zone 3 is the upland area beyond the wetland boundary. Hydric soils will not be present in zone 3, although in some cases hydrophytic vegetation can be observed adjacent to, and outside the boundary of, these wetlands. Within each site, nine research plots will be laid out along three transects as illustrated in Figure 2. Each of the transects will extend radially outwards from the center of the vernal pool (zone 1) through zone 2 and into the upland. Along each transect, a single plot will be centrally located within each of the hydrological zones. Location of the transects will be randomized based upon compass orientation. Elevation will be determined along each transect using appropriate tools such as a level or total station. Microtopographic differences will be documented by recording elevations at 1 meter intervals along the transects. Hydrological Measurements The depth of ponded water or the depth to the water table (below the surface) will be recorded at each site. Depth of ponded water will be measured using a staff gauge. Monitoring ports consisting of a well screen installed to a depth of 100 cm will be placed at each plot and water tables will be measured periodically (Figure 3). Along a single transect at each site, water table recording devices will be installed and programmed to record water table levels twice each day. The detailed (daily) data set from the recording devices will be extended to the other transects based on the periodic observations in the monitoring ports. Also along a single transect, nests of piezometers will be installed to help with interpretation of hydrological flow patterns. Soil Morphological Descriptions In the vicinity of each plot, a soil profile description will be made to a depth of 1 to 2 m according to standard protocols (Schoeneberger et al., 2012). Soil will be examined using a bucket augur. Horizons we be delineated and soil properties (texture, color, and presence of redoximorphic features) will be described in the field. Samples collected from each horizon will be stored for laboratory analysis. Morphological descriptions will be compared with approved field indicators of hydric soils to determine whether there is any need for additional hydric soil indicators for use in vernal pool ecosystems (USDA-Natural Resources Conservation Service, 2010). Vegetation Analysis Plant communities in each of the three zones will be assessed by methods outlined in the 1987 USACOE Wetland Delineation Manual (U.S. Army Corps of Engineers Environmental Laboratory, 1987) and the appropriate regional supplement (USACE, 2010, USACE, 2012, USACE, 2012). Climate Data In order to generalize and extend hydrological observations from the years of this study to the broader context, weather data will be obtained from the nearest weather station that maintains a long term (30+ years) record of daily precipitation and air temperatures. Daily records of precipitation and of minimum and maximum temperatures will be collected for the period of this study and will also be obtained for a minimum of the previous 30 years. Quantifying Carbon and Nitrogen Stocks Carbon and nitrogen stocks will be determined at plots along each transect (Vasilas et al., 2013). Within each plot, a section of aluminum tubing (sharpened on the leading edge) (60 cm long and 5 cm diameter) will be driven 50 cm into the soil. The tube will then be excavated and capped. Upon return to the lab, cores will be frozen to assist in extrusion. The extruded cores will be divided into vertical sections based on observed soil horizons, and the thickness of each horizon will be carefully measured. All soil material from each horizon will then be homogenized and weighed. The bulk density of each horizon will be then be calculated as the weight of the horizon divided by the horizon volume (calculated from the thickness of horizon multiplied by the cross-sectional area of the tube). The soil organic C percentage will be determined using a homogenized subsample of each horizon. Total carbon will be determined in duplicate by dry combustion (Nelson and Sommers, 1996) using a high temperature CNH Analyzer with an IR detector. These data will be used in conjunction with measurements of horizon thickness and bulk density to calculate the total C stocks in the soil to a depth of 50 cm. Soil Nitrate Soil nitrate will be measured on samples collected from each plot in the middle to end of the aerobic phase (August September). A single composite sample will be aggregated and homogenized from four to six replicate cores collected using a 30 cm push probe. Samples will be analyzed using the HACH 8171 method, similar to that used by Spokas et al. (2010). Soil Redox Assessment IRIS (indication of reduction in soil) tubes will be used to assess the reducing soil conditions within each plot (Rabenhorst, 2008; Rabenhorst and Burch, 2006; Rabenhorst et al., 2008; Vasilas et al., 2013). Five replicate IRIS tubes will be inserted at each plot to a depth of 50 cm. IRIS Tubes will be installed for a one month period in the Spring when water tables are expected to be high. The installation date at each site will be within one week of the beginning of the growing season as determined by US Army Corps of Engineers guidance (USACE, 2010; USACE, 2012; USACE, 2012). The extent of reduction on IRIS tubes will be determined by assessment using a mylar overlay (Rabenhorst, 2012). Organic Matter Decomposition The relative rates of organic matter decomposition will be evaluated by inserting wooden sticks into the soil and then extracting them at fixed intervals and measuring mass loss over time. Other studies have shown that wooden sticks can be used to indicate organic matter decomposition rates in several different types of settings (Baker, Lockaby, et al., 2001, Gulis, Rosemond, et al., 2004, Ostertag, Marín-Spiotta, et al., 2008). We will use northern white birch (Betula papyrifera) garden stakes that are approximately 300 x 16 x 3 mm in size. The stakes will be pre-dried (60C for 3 days to achieve constant weight) and weighed before being inserted vertically into a pilot hole in the soil, and then extracted at pre-determined intervals. The rate of decomposition will be estimated from differences in the starting and ending weights. Five replicate sticks will constitute a set. Five sets of pre-weighed sticks will be installed at each plot during the late Fall (November - December). One set of sticks will be removed each quarter (3 months intervals). When removed, the sticks will be gently washed to remove any attached soil material and then re-dried before being weighed. Overall weight loss will be determined by comparison of initial and final weights. Data Collection via Proximal Sensing Proximal sensing at selected sites will be conducted using two approaches. A ground-penetrating radar (GPR) unit with a 400 mHz antennae (Parsekian et al., 2012; Loisel et al., 2013) will be used to collect data in transects across the vernal pool wetlands. The high resolution of the 400 mHz antennae is expected to provide detailed information regarding the vertical and horizontal extent of soils and SOC stocks. GPR plots will be compared to soil profile descriptions made at each site enabling us to correlate GPR data with dominant groups of SOC bearing horizons, as illustrated in Figure 4. These data will be used to model SOC stocks and potential disturbance patterns (2D/3D)(GSSI, 2013; Saey et al., 2013; Vitharana et al., 2008). Selected wetlands will also be transected using electromagnetic induction (EMI) techniques (James et al., 2003; Robinson et al., 2008). We anticipate the EMI mapping will provide a more general assessment of wetland properties, while the GPR may provide more useful and detailed data due to the high resolution antennae. Data Analysis The study includes 7 sites across the Northeastern US grouped into 3 distinct geographic regions. Single data points collected will include redox measurements (n=315); duplicate carbon analysis (n = 630), duplicate soil nitrate analysis (n=126), and soil physical properties (horizonation, texture, and presence/absence of redoximorphic features). Time series data over the 5-year period will include daily precipitation, daily air temperature (maximum and minimum values), duration of hydroperiod (monthly for 5 years n=756 per year) and daily for 1 year (n= 700± - assuming 100 day measurement period), and decomposition rates at 5 time periods (n= 1575). Data will be subjected to an analysis of variance (ANOVA) using either PROC ANOVA or PROC GLM of the SAS System, Version 9.1.3 (SAS Institute, Inc., 2004) as a complete data set and then by regional group as warranted. When indicated by the ANOVA F-Test, means will be separated by the use of Duncans New Multiple Range Test, or other appropriate mean separation procedure. An Analysis of Covariance may be employed to determine differences in time series date for each site and between sites as appropriate. Additionally multiple regression may be employed to create prediction models for various data, i.e. decomposition rate as influenced by climate variables and soil properties. Ordination analysis will be undertaken as necessary when needed to better interpret the data.
Measurement of Progress and Results
- An annual project report highlighting the results for the previous year will be made available on the project website, and forwarded to participants in the related project focus areas.
- Participants will submit appropriate research findings for publication in peer reviewed journals and make presentations at local, regional, and national meetings.
- Any amendments related to National Indicators of Hydric Soils, or related documents, will be composed and submitted for consideration and final approval.
- Research sites will be incorporated into bi-annual Soil Survey Work Planning Conference fieldtrips and Northeast Graduate Student Pedology Field Tours. These fieldtrips and tours rotate throughout the region and run on opposite years.
- A final report will be issued at the conclusion of the project.
Outcomes or Projected Impacts
- This research will result in improved region-wide understanding of the soils and hydrology of vernal pools. We will learn and communicate to the scientific community how vernal pool ecosystems differ across the region in distribution, hydrology, periods of inundation (hydroperiod), redox chemistry, and carbon storage, flux, and accounting.
- We will continue our region-wide focus on hydric soils and hydric indicators to determine if there is a need for additional hydric soil indicators for vernal pool ecosystems. New hydric soil indicators will be proposed and submitted for inclusion as part of the National Indicators of Hydric Soils for the Northeast Supplement.
- Our region-wide approach (temperature gradient) to measure reducing conditions within soils (IRIS tubes along three-replicate transects) may have significant impact on how (when and for how long) reducing conditions within wetlands are measured and evaluated.
- One of our goals is to begin develop morphometric indices of the length of inundation (hydroperiod) within vernal pools. These indices would be invaluable to the ecological community trying to predict the hydroperiod relative the successful breeding of amphibians such as wood frogs and spotted salamanders that depend on these vernal pools for development of the larval stages of their species.
- Our spatial assessment at a landscape scale will provide an estimate of the current density of vernal pools within each of our subregions and allow for predictions of the numbers that have lost because of draining etc. This data will assist the scientific community in their debate of the merits of including isolated wetlands such as vernal pools into federal jurisdiction.
- Outcome/Impact 6 Our region-wide approach (temperature gradient) to measure SOC pools and decomposition rates in saturated and inundated soils will allow for better understanding of the effect of hydrology and temperature on carbon pools and sequestration in wetlands. Such data will provide insight into the effect of changing climate (temperature and precipitation) on carbon storage and accumulation.
Milestones(2015): Update project website with new project objectives and research deliverables for communication to the committee members. Organize a meeting for all participants to attend. Coordinate participants within specific research focus areas based on their expertise and interests. Begin to evaluate field sites using reconnaissance surveys to identify appropriate sites for detailed studies.
(2016): Establish appropriate field sites for detailed studies based on reconnaissance surveys. Establish replicate transects from upland to wetland areas with the longest inundation. Instrument transects to measure water table depth and periods and duration of inundation. Install IRIS tubes and decomposition materials. Meet to further discuss coordination and strategies for instrumentation, mapping, and sampling. Update web site to include site information and discussions during the regional fieldtrip to selected sites. Visit selected sites during biannual Northeast Pedology Fieldtrip.
(2017): Maintain monitoring, decomposition experiments, and mapping. Describe and sample soils within various hydropedological entities (i.e. upland, wetland, inundated). Begin characterization efforts. Begin to analyze morphologic data from inundated, hydric, and seasonally saturated soils with site specific monitoring data. Collect and analyze carbon storage and sequestration data. Meet to discuss first two years of project and initial results. Consider additional questions and studies. Visit selected sites during region soil survey work planning conference tours. Update web site to include site and monitoring information and discussions during the fieldtrip to selected sites.
(2018): Continue the monitoring, decomposition experiments, and mapping. Finish describing and sampling the soils within the various hydropedological entities (i.e. upland, wetland, inundated). Continue the characterization efforts. Continue to analyze the morphologic data from the inundated, hydric, and seasonally saturated soils relative to inundation, saturation, temperature, and redox potential data. Continue to collect and analyze carbon storage and sequestration data. Meet to discuss the initial three years of the project and to begin to develop and construct research proposals and peer-reviewed papers based on the project. Visit selected sites during biannual Northeast Pedology Fieldtrip. Update web site to include new monitoring and analytical information and discussions during the regional fieldtrip to selected sites.
(2019): Complete analysis, synthesize results across the region, and write final report and other output works.
Projected ParticipationView Appendix E: Participation
Results from the proposed multistate project activities will be published as project reports, on the project web site, and as peer-reviewed publications. Participating members involved in undergraduate teaching, graduate student advisement, and extension activities associated with Land Grant Universities will promote the general dissemination of knowledge developed from the proposed project activities. Research sites will be visited on local, regional, and national pedology, hydric soil, and soil-environmental science fieldtrips and workshops. Northeast Pedology Fieldtrips have been run at least every two years since 1985. Participants include National Cooperative Soil Survey personnel from the NE region and graduate students from participating schools. Fieldtrips are run every other year during the region soil survey work planning conferences. Annual fieldtrips are also run by the New England Hydric Soils Technical Committee and the Mid-Atlantic Hydric Soils Committee. These committees are made up of university faculty, consulting soil scientists, NRCS soil scientists, and state and regional regulators.
The core membership in the multi-state project will likely come from the current NE-1038 Multistate project including: Patrick Drohan (Penn State University), John Galbraith (Virginia Tech), Brian Needelman (University of Maryland), Martin Rabenhorst (University of Maryland), Mark Stolt (University of Rhode Island), James Thompson (West Virginia University), Bruce Vasilas (University of Delaware), and Mickey Spokas (University of Massachusetts).
A Chair, a Chair-elect, and a Secretary will be selected from the above participants. Representatives from the member institutions will meet at least annually to assign tasks and review progress on the current research project. Additional participants with expertise in pedology, mineralogy, soil ecology, hydrology, soil-environmental science, and other related disciplines will be invited to join the project.
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